Remove damned ancient DOS line endings from Irrlicht. Hopefully I did not go overboard.

53 files changed, 22715 insertions, 22715 deletions

diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/README.txt b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/README.txt
index 7e9b7d0..bcd433d 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/README.txt
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/README.txt
@@ -1,4 +1,4 @@
-

-This "contrib" directory contains contributions which are not necessarily under

-the libpng license, although all are open source.  They are not part of

-libpng proper and are not used for building the library.

+
+This "contrib" directory contains contributions which are not necessarily under
+the libpng license, although all are open source.  They are not part of
+libpng proper and are not used for building the library.
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/COPYING b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/COPYING
index c2d382b..a3e9774 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/COPYING
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/COPYING
@@ -1,340 +1,340 @@
-                    GNU GENERAL PUBLIC LICENSE

-                       Version 2, June 1991

-

- Copyright (C) 1989, 1991 Free Software Foundation, Inc.

-     59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

- Everyone is permitted to copy and distribute verbatim copies

- of this license document, but changing it is not allowed.

-

-                            Preamble

-

-  The licenses for most software are designed to take away your

-freedom to share and change it.  By contrast, the GNU General Public

-License is intended to guarantee your freedom to share and change free

-software--to make sure the software is free for all its users.  This

-General Public License applies to most of the Free Software

-Foundation's software and to any other program whose authors commit to

-using it.  (Some other Free Software Foundation software is covered by

-the GNU Library General Public License instead.)  You can apply it to

-your programs, too.

-

-  When we speak of free software, we are referring to freedom, not

-price.  Our General Public Licenses are designed to make sure that you

-have the freedom to distribute copies of free software (and charge for

-this service if you wish), that you receive source code or can get it

-if you want it, that you can change the software or use pieces of it

-in new free programs; and that you know you can do these things.

-

-  To protect your rights, we need to make restrictions that forbid

-anyone to deny you these rights or to ask you to surrender the rights.

-These restrictions translate to certain responsibilities for you if you

-distribute copies of the software, or if you modify it.

-

-  For example, if you distribute copies of such a program, whether

-gratis or for a fee, you must give the recipients all the rights that

-you have.  You must make sure that they, too, receive or can get the

-source code.  And you must show them these terms so they know their

-rights.

-

-  We protect your rights with two steps: (1) copyright the software, and

-(2) offer you this license which gives you legal permission to copy,

-distribute and/or modify the software.

-

-  Also, for each author's protection and ours, we want to make certain

-that everyone understands that there is no warranty for this free

-software.  If the software is modified by someone else and passed on, we

-want its recipients to know that what they have is not the original, so

-that any problems introduced by others will not reflect on the original

-authors' reputations.

-

-  Finally, any free program is threatened constantly by software

-patents.  We wish to avoid the danger that redistributors of a free

-program will individually obtain patent licenses, in effect making the

-program proprietary.  To prevent this, we have made it clear that any

-patent must be licensed for everyone's free use or not licensed at all.

-

-  The precise terms and conditions for copying, distribution and

-modification follow.

-

-                    GNU GENERAL PUBLIC LICENSE

-   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION

-

-  0. This License applies to any program or other work which contains

-a notice placed by the copyright holder saying it may be distributed

-under the terms of this General Public License.  The "Program", below,

-refers to any such program or work, and a "work based on the Program"

-means either the Program or any derivative work under copyright law:

-that is to say, a work containing the Program or a portion of it,

-either verbatim or with modifications and/or translated into another

-language.  (Hereinafter, translation is included without limitation in

-the term "modification".)  Each licensee is addressed as "you".

-

-Activities other than copying, distribution and modification are not

-covered by this License; they are outside its scope.  The act of

-running the Program is not restricted, and the output from the Program

-is covered only if its contents constitute a work based on the

-Program (independent of having been made by running the Program).

-Whether that is true depends on what the Program does.

-

-  1. You may copy and distribute verbatim copies of the Program's

-source code as you receive it, in any medium, provided that you

-conspicuously and appropriately publish on each copy an appropriate

-copyright notice and disclaimer of warranty; keep intact all the

-notices that refer to this License and to the absence of any warranty;

-and give any other recipients of the Program a copy of this License

-along with the Program.

-

-You may charge a fee for the physical act of transferring a copy, and

-you may at your option offer warranty protection in exchange for a fee.

-

-  2. You may modify your copy or copies of the Program or any portion

-of it, thus forming a work based on the Program, and copy and

-distribute such modifications or work under the terms of Section 1

-above, provided that you also meet all of these conditions:

-

-    a) You must cause the modified files to carry prominent notices

-    stating that you changed the files and the date of any change.

-

-    b) You must cause any work that you distribute or publish, that in

-    whole or in part contains or is derived from the Program or any

-    part thereof, to be licensed as a whole at no charge to all third

-    parties under the terms of this License.

-

-    c) If the modified program normally reads commands interactively

-    when run, you must cause it, when started running for such

-    interactive use in the most ordinary way, to print or display an

-    announcement including an appropriate copyright notice and a

-    notice that there is no warranty (or else, saying that you provide

-    a warranty) and that users may redistribute the program under

-    these conditions, and telling the user how to view a copy of this

-    License.  (Exception: if the Program itself is interactive but

-    does not normally print such an announcement, your work based on

-    the Program is not required to print an announcement.)

-

-These requirements apply to the modified work as a whole.  If

-identifiable sections of that work are not derived from the Program,

-and can be reasonably considered independent and separate works in

-themselves, then this License, and its terms, do not apply to those

-sections when you distribute them as separate works.  But when you

-distribute the same sections as part of a whole which is a work based

-on the Program, the distribution of the whole must be on the terms of

-this License, whose permissions for other licensees extend to the

-entire whole, and thus to each and every part regardless of who wrote it.

-

-Thus, it is not the intent of this section to claim rights or contest

-your rights to work written entirely by you; rather, the intent is to

-exercise the right to control the distribution of derivative or

-collective works based on the Program.

-

-In addition, mere aggregation of another work not based on the Program

-with the Program (or with a work based on the Program) on a volume of

-a storage or distribution medium does not bring the other work under

-the scope of this License.

-

-  3. You may copy and distribute the Program (or a work based on it,

-under Section 2) in object code or executable form under the terms of

-Sections 1 and 2 above provided that you also do one of the following:

-

-    a) Accompany it with the complete corresponding machine-readable

-    source code, which must be distributed under the terms of Sections

-    1 and 2 above on a medium customarily used for software interchange; or,

-

-    b) Accompany it with a written offer, valid for at least three

-    years, to give any third party, for a charge no more than your

-    cost of physically performing source distribution, a complete

-    machine-readable copy of the corresponding source code, to be

-    distributed under the terms of Sections 1 and 2 above on a medium

-    customarily used for software interchange; or,

-

-    c) Accompany it with the information you received as to the offer

-    to distribute corresponding source code.  (This alternative is

-    allowed only for noncommercial distribution and only if you

-    received the program in object code or executable form with such

-    an offer, in accord with Subsection b above.)

-

-The source code for a work means the preferred form of the work for

-making modifications to it.  For an executable work, complete source

-code means all the source code for all modules it contains, plus any

-associated interface definition files, plus the scripts used to

-control compilation and installation of the executable.  However, as a

-special exception, the source code distributed need not include

-anything that is normally distributed (in either source or binary

-form) with the major components (compiler, kernel, and so on) of the

-operating system on which the executable runs, unless that component

-itself accompanies the executable.

-

-If distribution of executable or object code is made by offering

-access to copy from a designated place, then offering equivalent

-access to copy the source code from the same place counts as

-distribution of the source code, even though third parties are not

-compelled to copy the source along with the object code.

-

-  4. You may not copy, modify, sublicense, or distribute the Program

-except as expressly provided under this License.  Any attempt

-otherwise to copy, modify, sublicense or distribute the Program is

-void, and will automatically terminate your rights under this License.

-However, parties who have received copies, or rights, from you under

-this License will not have their licenses terminated so long as such

-parties remain in full compliance.

-

-  5. You are not required to accept this License, since you have not

-signed it.  However, nothing else grants you permission to modify or

-distribute the Program or its derivative works.  These actions are

-prohibited by law if you do not accept this License.  Therefore, by

-modifying or distributing the Program (or any work based on the

-Program), you indicate your acceptance of this License to do so, and

-all its terms and conditions for copying, distributing or modifying

-the Program or works based on it.

-

-  6. Each time you redistribute the Program (or any work based on the

-Program), the recipient automatically receives a license from the

-original licensor to copy, distribute or modify the Program subject to

-these terms and conditions.  You may not impose any further

-restrictions on the recipients' exercise of the rights granted herein.

-You are not responsible for enforcing compliance by third parties to

-this License.

-

-  7. If, as a consequence of a court judgment or allegation of patent

-infringement or for any other reason (not limited to patent issues),

-conditions are imposed on you (whether by court order, agreement or

-otherwise) that contradict the conditions of this License, they do not

-excuse you from the conditions of this License.  If you cannot

-distribute so as to satisfy simultaneously your obligations under this

-License and any other pertinent obligations, then as a consequence you

-may not distribute the Program at all.  For example, if a patent

-license would not permit royalty-free redistribution of the Program by

-all those who receive copies directly or indirectly through you, then

-the only way you could satisfy both it and this License would be to

-refrain entirely from distribution of the Program.

-

-If any portion of this section is held invalid or unenforceable under

-any particular circumstance, the balance of the section is intended to

-apply and the section as a whole is intended to apply in other

-circumstances.

-

-It is not the purpose of this section to induce you to infringe any

-patents or other property right claims or to contest validity of any

-such claims; this section has the sole purpose of protecting the

-integrity of the free software distribution system, which is

-implemented by public license practices.  Many people have made

-generous contributions to the wide range of software distributed

-through that system in reliance on consistent application of that

-system; it is up to the author/donor to decide if he or she is willing

-to distribute software through any other system and a licensee cannot

-impose that choice.

-

-This section is intended to make thoroughly clear what is believed to

-be a consequence of the rest of this License.

-

-  8. If the distribution and/or use of the Program is restricted in

-certain countries either by patents or by copyrighted interfaces, the

-original copyright holder who places the Program under this License

-may add an explicit geographical distribution limitation excluding

-those countries, so that distribution is permitted only in or among

-countries not thus excluded.  In such case, this License incorporates

-the limitation as if written in the body of this License.

-

-  9. The Free Software Foundation may publish revised and/or new versions

-of the General Public License from time to time.  Such new versions will

-be similar in spirit to the present version, but may differ in detail to

-address new problems or concerns.

-

-Each version is given a distinguishing version number.  If the Program

-specifies a version number of this License which applies to it and "any

-later version", you have the option of following the terms and conditions

-either of that version or of any later version published by the Free

-Software Foundation.  If the Program does not specify a version number of

-this License, you may choose any version ever published by the Free Software

-Foundation.

-

-  10. If you wish to incorporate parts of the Program into other free

-programs whose distribution conditions are different, write to the author

-to ask for permission.  For software which is copyrighted by the Free

-Software Foundation, write to the Free Software Foundation; we sometimes

-make exceptions for this.  Our decision will be guided by the two goals

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-of promoting the sharing and reuse of software generally.

-

-                            NO WARRANTY

-

-  11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY

-FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN

-OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES

-PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED

-OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF

-MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS

-TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE

-PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,

-REPAIR OR CORRECTION.

-

-  12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING

-WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR

-REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,

-INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING

-OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED

-TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY

-YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER

-PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE

-POSSIBILITY OF SUCH DAMAGES.

-

-                     END OF TERMS AND CONDITIONS

-

-            How to Apply These Terms to Your New Programs

-

-  If you develop a new program, and you want it to be of the greatest

-possible use to the public, the best way to achieve this is to make it

-free software which everyone can redistribute and change under these terms.

-

-  To do so, attach the following notices to the program.  It is safest

-to attach them to the start of each source file to most effectively

-convey the exclusion of warranty; and each file should have at least

-the "copyright" line and a pointer to where the full notice is found.

-

-    <one line to give the program's name and a brief idea of what it does.>

-    Copyright (C) <year>  <name of author>

-

-    This program is free software; you can redistribute it and/or modify

-    it under the terms of the GNU General Public License as published by

-    the Free Software Foundation; either version 2 of the License, or

-    (at your option) any later version.

-

-    This program is distributed in the hope that it will be useful,

-    but WITHOUT ANY WARRANTY; without even the implied warranty of

-    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

-    GNU General Public License for more details.

-

-    You should have received a copy of the GNU General Public License

-    along with this program; if not, write to the Free Software

-    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

-

-

-Also add information on how to contact you by electronic and paper mail.

-

-If the program is interactive, make it output a short notice like this

-when it starts in an interactive mode:

-

-    Gnomovision version 69, Copyright (C) year  name of author

-    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.

-    This is free software, and you are welcome to redistribute it

-    under certain conditions; type `show c' for details.

-

-The hypothetical commands `show w' and `show c' should show the appropriate

-parts of the General Public License.  Of course, the commands you use may

-be called something other than `show w' and `show c'; they could even be

-mouse-clicks or menu items--whatever suits your program.

-

-You should also get your employer (if you work as a programmer) or your

-school, if any, to sign a "copyright disclaimer" for the program, if

-necessary.  Here is a sample; alter the names:

-

-  Yoyodyne, Inc., hereby disclaims all copyright interest in the program

-  `Gnomovision' (which makes passes at compilers) written by James Hacker.

-

-  <signature of Ty Coon>, 1 April 1989

-  Ty Coon, President of Vice

-

-This General Public License does not permit incorporating your program into

-proprietary programs.  If your program is a subroutine library, you may

-consider it more useful to permit linking proprietary applications with the

-library.  If this is what you want to do, use the GNU Library General

-Public License instead of this License.

+                    GNU GENERAL PUBLIC LICENSE
+                       Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.
+     59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
+
+  The licenses for most software are designed to take away your
+freedom to share and change it.  By contrast, the GNU General Public
+License is intended to guarantee your freedom to share and change free
+software--to make sure the software is free for all its users.  This
+General Public License applies to most of the Free Software
+Foundation's software and to any other program whose authors commit to
+using it.  (Some other Free Software Foundation software is covered by
+the GNU Library General Public License instead.)  You can apply it to
+your programs, too.
+
+  When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+this service if you wish), that you receive source code or can get it
+if you want it, that you can change the software or use pieces of it
+in new free programs; and that you know you can do these things.
+
+  To protect your rights, we need to make restrictions that forbid
+anyone to deny you these rights or to ask you to surrender the rights.
+These restrictions translate to certain responsibilities for you if you
+distribute copies of the software, or if you modify it.
+
+  For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must give the recipients all the rights that
+you have.  You must make sure that they, too, receive or can get the
+source code.  And you must show them these terms so they know their
+rights.
+
+  We protect your rights with two steps: (1) copyright the software, and
+(2) offer you this license which gives you legal permission to copy,
+distribute and/or modify the software.
+
+  Also, for each author's protection and ours, we want to make certain
+that everyone understands that there is no warranty for this free
+software.  If the software is modified by someone else and passed on, we
+want its recipients to know that what they have is not the original, so
+that any problems introduced by others will not reflect on the original
+authors' reputations.
+
+  Finally, any free program is threatened constantly by software
+patents.  We wish to avoid the danger that redistributors of a free
+program will individually obtain patent licenses, in effect making the
+program proprietary.  To prevent this, we have made it clear that any
+patent must be licensed for everyone's free use or not licensed at all.
+
+  The precise terms and conditions for copying, distribution and
+modification follow.
+
+                    GNU GENERAL PUBLIC LICENSE
+   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
+  0. This License applies to any program or other work which contains
+a notice placed by the copyright holder saying it may be distributed
+under the terms of this General Public License.  The "Program", below,
+refers to any such program or work, and a "work based on the Program"
+means either the Program or any derivative work under copyright law:
+that is to say, a work containing the Program or a portion of it,
+either verbatim or with modifications and/or translated into another
+language.  (Hereinafter, translation is included without limitation in
+the term "modification".)  Each licensee is addressed as "you".
+
+Activities other than copying, distribution and modification are not
+covered by this License; they are outside its scope.  The act of
+running the Program is not restricted, and the output from the Program
+is covered only if its contents constitute a work based on the
+Program (independent of having been made by running the Program).
+Whether that is true depends on what the Program does.
+
+  1. You may copy and distribute verbatim copies of the Program's
+source code as you receive it, in any medium, provided that you
+conspicuously and appropriately publish on each copy an appropriate
+copyright notice and disclaimer of warranty; keep intact all the
+notices that refer to this License and to the absence of any warranty;
+and give any other recipients of the Program a copy of this License
+along with the Program.
+
+You may charge a fee for the physical act of transferring a copy, and
+you may at your option offer warranty protection in exchange for a fee.
+
+  2. You may modify your copy or copies of the Program or any portion
+of it, thus forming a work based on the Program, and copy and
+distribute such modifications or work under the terms of Section 1
+above, provided that you also meet all of these conditions:
+
+    a) You must cause the modified files to carry prominent notices
+    stating that you changed the files and the date of any change.
+
+    b) You must cause any work that you distribute or publish, that in
+    whole or in part contains or is derived from the Program or any
+    part thereof, to be licensed as a whole at no charge to all third
+    parties under the terms of this License.
+
+    c) If the modified program normally reads commands interactively
+    when run, you must cause it, when started running for such
+    interactive use in the most ordinary way, to print or display an
+    announcement including an appropriate copyright notice and a
+    notice that there is no warranty (or else, saying that you provide
+    a warranty) and that users may redistribute the program under
+    these conditions, and telling the user how to view a copy of this
+    License.  (Exception: if the Program itself is interactive but
+    does not normally print such an announcement, your work based on
+    the Program is not required to print an announcement.)
+
+These requirements apply to the modified work as a whole.  If
+identifiable sections of that work are not derived from the Program,
+and can be reasonably considered independent and separate works in
+themselves, then this License, and its terms, do not apply to those
+sections when you distribute them as separate works.  But when you
+distribute the same sections as part of a whole which is a work based
+on the Program, the distribution of the whole must be on the terms of
+this License, whose permissions for other licensees extend to the
+entire whole, and thus to each and every part regardless of who wrote it.
+
+Thus, it is not the intent of this section to claim rights or contest
+your rights to work written entirely by you; rather, the intent is to
+exercise the right to control the distribution of derivative or
+collective works based on the Program.
+
+In addition, mere aggregation of another work not based on the Program
+with the Program (or with a work based on the Program) on a volume of
+a storage or distribution medium does not bring the other work under
+the scope of this License.
+
+  3. You may copy and distribute the Program (or a work based on it,
+under Section 2) in object code or executable form under the terms of
+Sections 1 and 2 above provided that you also do one of the following:
+
+    a) Accompany it with the complete corresponding machine-readable
+    source code, which must be distributed under the terms of Sections
+    1 and 2 above on a medium customarily used for software interchange; or,
+
+    b) Accompany it with a written offer, valid for at least three
+    years, to give any third party, for a charge no more than your
+    cost of physically performing source distribution, a complete
+    machine-readable copy of the corresponding source code, to be
+    distributed under the terms of Sections 1 and 2 above on a medium
+    customarily used for software interchange; or,
+
+    c) Accompany it with the information you received as to the offer
+    to distribute corresponding source code.  (This alternative is
+    allowed only for noncommercial distribution and only if you
+    received the program in object code or executable form with such
+    an offer, in accord with Subsection b above.)
+
+The source code for a work means the preferred form of the work for
+making modifications to it.  For an executable work, complete source
+code means all the source code for all modules it contains, plus any
+associated interface definition files, plus the scripts used to
+control compilation and installation of the executable.  However, as a
+special exception, the source code distributed need not include
+anything that is normally distributed (in either source or binary
+form) with the major components (compiler, kernel, and so on) of the
+operating system on which the executable runs, unless that component
+itself accompanies the executable.
+
+If distribution of executable or object code is made by offering
+access to copy from a designated place, then offering equivalent
+access to copy the source code from the same place counts as
+distribution of the source code, even though third parties are not
+compelled to copy the source along with the object code.
+
+  4. You may not copy, modify, sublicense, or distribute the Program
+except as expressly provided under this License.  Any attempt
+otherwise to copy, modify, sublicense or distribute the Program is
+void, and will automatically terminate your rights under this License.
+However, parties who have received copies, or rights, from you under
+this License will not have their licenses terminated so long as such
+parties remain in full compliance.
+
+  5. You are not required to accept this License, since you have not
+signed it.  However, nothing else grants you permission to modify or
+distribute the Program or its derivative works.  These actions are
+prohibited by law if you do not accept this License.  Therefore, by
+modifying or distributing the Program (or any work based on the
+Program), you indicate your acceptance of this License to do so, and
+all its terms and conditions for copying, distributing or modifying
+the Program or works based on it.
+
+  6. Each time you redistribute the Program (or any work based on the
+Program), the recipient automatically receives a license from the
+original licensor to copy, distribute or modify the Program subject to
+these terms and conditions.  You may not impose any further
+restrictions on the recipients' exercise of the rights granted herein.
+You are not responsible for enforcing compliance by third parties to
+this License.
+
+  7. If, as a consequence of a court judgment or allegation of patent
+infringement or for any other reason (not limited to patent issues),
+conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License.  If you cannot
+distribute so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you
+may not distribute the Program at all.  For example, if a patent
+license would not permit royalty-free redistribution of the Program by
+all those who receive copies directly or indirectly through you, then
+the only way you could satisfy both it and this License would be to
+refrain entirely from distribution of the Program.
+
+If any portion of this section is held invalid or unenforceable under
+any particular circumstance, the balance of the section is intended to
+apply and the section as a whole is intended to apply in other
+circumstances.
+
+It is not the purpose of this section to induce you to infringe any
+patents or other property right claims or to contest validity of any
+such claims; this section has the sole purpose of protecting the
+integrity of the free software distribution system, which is
+implemented by public license practices.  Many people have made
+generous contributions to the wide range of software distributed
+through that system in reliance on consistent application of that
+system; it is up to the author/donor to decide if he or she is willing
+to distribute software through any other system and a licensee cannot
+impose that choice.
+
+This section is intended to make thoroughly clear what is believed to
+be a consequence of the rest of this License.
+
+  8. If the distribution and/or use of the Program is restricted in
+certain countries either by patents or by copyrighted interfaces, the
+original copyright holder who places the Program under this License
+may add an explicit geographical distribution limitation excluding
+those countries, so that distribution is permitted only in or among
+countries not thus excluded.  In such case, this License incorporates
+the limitation as if written in the body of this License.
+
+  9. The Free Software Foundation may publish revised and/or new versions
+of the General Public License from time to time.  Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+Each version is given a distinguishing version number.  If the Program
+specifies a version number of this License which applies to it and "any
+later version", you have the option of following the terms and conditions
+either of that version or of any later version published by the Free
+Software Foundation.  If the Program does not specify a version number of
+this License, you may choose any version ever published by the Free Software
+Foundation.
+
+  10. If you wish to incorporate parts of the Program into other free
+programs whose distribution conditions are different, write to the author
+to ask for permission.  For software which is copyrighted by the Free
+Software Foundation, write to the Free Software Foundation; we sometimes
+make exceptions for this.  Our decision will be guided by the two goals
+of preserving the free status of all derivatives of our free software and
+of promoting the sharing and reuse of software generally.
+
+                            NO WARRANTY
+
+  11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
+FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN
+OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
+PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
+OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS
+TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE
+PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
+REPAIR OR CORRECTION.
+
+  12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
+REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
+INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
+OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
+TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
+YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
+PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGES.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+
+Also add information on how to contact you by electronic and paper mail.
+
+If the program is interactive, make it output a short notice like this
+when it starts in an interactive mode:
+
+    Gnomovision version 69, Copyright (C) year  name of author
+    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, the commands you use may
+be called something other than `show w' and `show c'; they could even be
+mouse-clicks or menu items--whatever suits your program.
+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the program, if
+necessary.  Here is a sample; alter the names:
+
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the program
+  `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+  <signature of Ty Coon>, 1 April 1989
+  Ty Coon, President of Vice
+
+This General Public License does not permit incorporating your program into
+proprietary programs.  If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library.  If this is what you want to do, use the GNU Library General
+Public License instead of this License.
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/LICENSE b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/LICENSE
index 40a0c8e..d956717 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/LICENSE
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/LICENSE
@@ -1,50 +1,50 @@
-  ---------------------------------------------------------------------------

-

-      Copyright (c) 1998-2008 Greg Roelofs.  All rights reserved.

-

-      This software is provided "as is," without warranty of any kind,

-      express or implied.  In no event shall the author or contributors

-      be held liable for any damages arising in any way from the use of

-      this software.

-

-      The contents of this file are DUAL-LICENSED.  You may modify and/or

-      redistribute this software according to the terms of one of the

-      following two licenses (at your option):

-

-

-      LICENSE 1 ("BSD-like with advertising clause"):

-

-      Permission is granted to anyone to use this software for any purpose,

-      including commercial applications, and to alter it and redistribute

-      it freely, subject to the following restrictions:

-

-      1. Redistributions of source code must retain the above copyright

-         notice, disclaimer, and this list of conditions.

-      2. Redistributions in binary form must reproduce the above copyright

-         notice, disclaimer, and this list of conditions in the documenta-

-         tion and/or other materials provided with the distribution.

-      3. All advertising materials mentioning features or use of this

-         software must display the following acknowledgment:

-

-            This product includes software developed by Greg Roelofs

-            and contributors for the book, "PNG: The Definitive Guide,"

-            published by O'Reilly and Associates.

-

-

-      LICENSE 2 (GNU GPL v2 or later):

-

-      This program is free software; you can redistribute it and/or modify

-      it under the terms of the GNU General Public License as published by

-      the Free Software Foundation; either version 2 of the License, or

-      (at your option) any later version.

-

-      This program is distributed in the hope that it will be useful,

-      but WITHOUT ANY WARRANTY; without even the implied warranty of

-      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

-      GNU General Public License for more details.

-

-      You should have received a copy of the GNU General Public License

-      along with this program; if not, write to the Free Software Foundation,

-      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

-

-  ---------------------------------------------------------------------------

+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-2008 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      The contents of this file are DUAL-LICENSED.  You may modify and/or
+      redistribute this software according to the terms of one of the
+      following two licenses (at your option):
+
+
+      LICENSE 1 ("BSD-like with advertising clause"):
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+
+      LICENSE 2 (GNU GPL v2 or later):
+
+      This program is free software; you can redistribute it and/or modify
+      it under the terms of the GNU General Public License as published by
+      the Free Software Foundation; either version 2 of the License, or
+      (at your option) any later version.
+
+      This program is distributed in the hope that it will be useful,
+      but WITHOUT ANY WARRANTY; without even the implied warranty of
+      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+      GNU General Public License for more details.
+
+      You should have received a copy of the GNU General Public License
+      along with this program; if not, write to the Free Software Foundation,
+      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+  ---------------------------------------------------------------------------
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/Makefile.mingw32 b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/Makefile.mingw32
index a736556..e70a59a 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/Makefile.mingw32
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/Makefile.mingw32
@@ -1,130 +1,130 @@
-# Sample makefile for rpng-win / rpng2-win / wpng using mingw32-gcc and make.

-# Greg Roelofs

-# Last modified:  2 June 2007

-#

-#       The programs built by this makefile are described in the book,

-#       "PNG:  The Definitive Guide," by Greg Roelofs (O'Reilly and

-#       Associates, 1999).  Go buy a copy, eh?  Well, OK, it's not

-#       generally for sale anymore, but it's the thought that counts,

-#       right?  (Hint:  http://www.libpng.org/pub/png/book/ )

-#

-# Invoke this makefile from a DOS-prompt window via:

-#

-#       make -f Makefile.mingw32

-#

-# This makefile assumes libpng and zlib have already been built or downloaded

-# and are in subdirectories at the same level as the current subdirectory

-# (as indicated by the PNGDIR and ZDIR macros below).  It makes no assumptions

-# at all about the mingw32 installation tree (W32DIR).  Edit as appropriate.

-#

-# Note that the names of the dynamic and static libpng and zlib libraries

-# used below may change in later releases of the libraries.  This makefile

-# builds both statically and dynamically linked executables by default.

-# (You need only one set, but for testing it can be handy to have both.)

-

-

-# macros --------------------------------------------------------------------

-

-#PNGDIR = ../..#                for libpng-x.y.z/contrib/gregbook builds

-PNGDIR = ../libpng-win32

-PNGINC = -I$(PNGDIR)

-PNGLIBd = $(PNGDIR)/libpng.dll.a        # dynamically linked

-PNGLIBs = $(PNGDIR)/libpng.a            # statically linked, local libpng

-

-#ZDIR = ../../../zlib-win32#    for libpng-x.y.z/contrib/gregbook builds

-ZDIR = ../zlib-win32

-ZINC = -I$(ZDIR)

-ZLIBd = $(ZDIR)/libzdll.a

-ZLIBs = $(ZDIR)/libz.a

-

-# change this to be the path where mingw32 installs its stuff:

-W32DIR =

-#W32DIR = /usr/local/cross-tools/i386-mingw32msvc

-W32INC = -I$(W32DIR)/include

-W32LIB = $(W32DIR)/lib/libuser32.a $(W32DIR)/lib/libgdi32.a

-

-CC = gcc

-#CC = i386-mingw32msvc-gcc #    e.g., Linux -> Win32 cross-compilation

-LD = $(CC)

-RM = rm -f

-CFLAGS = -O -Wall $(INCS) $(MINGW_CCFLAGS)

-# [note that -Wall is a gcc-specific compilation flag ("most warnings on")]

-# [-ansi, -pedantic and -W can also be used]

-LDFLAGS = $(MINGW_LDFLAGS)

-O = .o

-E = .exe

-

-INCS = $(PNGINC) $(ZINC) $(W32INC)

-RLIBSd = $(PNGLIBd) $(ZLIBd) $(W32LIB) -lm

-RLIBSs = $(PNGLIBs) $(ZLIBs) $(W32LIB) -lm

-WLIBSd = $(PNGLIBd) $(ZLIBd)

-WLIBSs = $(PNGLIBs) $(ZLIBs)

-

-RPNG   = rpng-win

-RPNG2  = rpng2-win

-WPNG   = wpng

-

-ROBJSd  = $(RPNG)$(O) readpng.pic$(O)

-ROBJS2d = $(RPNG2)$(O) readpng2.pic$(O)

-WOBJSd  = $(WPNG)$(O) writepng.pic$(O)

-

-RPNGs  = $(RPNG)-static

-RPNG2s = $(RPNG2)-static

-WPNGs  = $(WPNG)-static

-

-ROBJSs  = $(RPNG)$(O) readpng$(O)

-ROBJS2s = $(RPNG2)$(O) readpng2$(O)

-WOBJSs  = $(WPNG)$(O) writepng$(O)

-

-STATIC_EXES  = $(RPNGs)$(E) $(RPNG2s)$(E) $(WPNGs)$(E)

-DYNAMIC_EXES = $(RPNG)$(E) $(RPNG2)$(E) $(WPNG)$(E)

-

-EXES = $(STATIC_EXES) $(DYNAMIC_EXES)

-

-

-# implicit make rules -------------------------------------------------------

-

-.c$(O):

-        $(CC) -c $(CFLAGS) $<

-

-%.pic$(O): %.c

-        $(CC) -c $(CFLAGS) -DPNG_BUILD_DLL -o $@ $<

-

-

-# dependencies --------------------------------------------------------------

-

-all:  $(EXES)

-

-$(RPNGs)$(E): $(ROBJSs)

-        $(LD) $(LDFLAGS) -o $@ $(ROBJSs) $(RLIBSs)

-

-$(RPNG)$(E): $(ROBJSd)

-        $(LD) $(LDFLAGS) -o $@ $(ROBJSd) $(RLIBSd)

-

-$(RPNG2s)$(E): $(ROBJS2s)

-        $(LD) $(LDFLAGS) -o $@ $(ROBJS2s) $(RLIBSs)

-

-$(RPNG2)$(E): $(ROBJS2d)

-        $(LD) $(LDFLAGS) -o $@ $(ROBJS2d) $(RLIBSd)

-

-$(WPNGs)$(E): $(WOBJSs)

-        $(LD) $(LDFLAGS) -o $@ $(WOBJSs) $(WLIBSs)

-

-$(WPNG)$(E): $(WOBJSd)

-        $(LD) $(LDFLAGS) -o $@ $(WOBJSd) $(WLIBSd)

-

-$(RPNG)$(O):    $(RPNG).c readpng.h

-$(RPNG2)$(O):   $(RPNG2).c readpng2.h

-$(WPNG)$(O):    $(WPNG).c writepng.h

-

-readpng$(O) readpng.pic$(O):    readpng.c readpng.h

-readpng2$(O) readpng2.pic$(O):  readpng2.c readpng2.h

-writepng$(O) writepng.pic$(O):  writepng.c writepng.h

-

-

-# maintenance ---------------------------------------------------------------

-

-clean:

-        $(RM) $(EXES)

-        $(RM) $(ROBJSs) $(ROBJS2s) $(WOBJSs)

-        $(RM) $(ROBJSd) $(ROBJS2d) $(WOBJSd)

+# Sample makefile for rpng-win / rpng2-win / wpng using mingw32-gcc and make.
+# Greg Roelofs
+# Last modified:  2 June 2007
+#
+#       The programs built by this makefile are described in the book,
+#       "PNG:  The Definitive Guide," by Greg Roelofs (O'Reilly and
+#       Associates, 1999).  Go buy a copy, eh?  Well, OK, it's not
+#       generally for sale anymore, but it's the thought that counts,
+#       right?  (Hint:  http://www.libpng.org/pub/png/book/ )
+#
+# Invoke this makefile from a DOS-prompt window via:
+#
+#       make -f Makefile.mingw32
+#
+# This makefile assumes libpng and zlib have already been built or downloaded
+# and are in subdirectories at the same level as the current subdirectory
+# (as indicated by the PNGDIR and ZDIR macros below).  It makes no assumptions
+# at all about the mingw32 installation tree (W32DIR).  Edit as appropriate.
+#
+# Note that the names of the dynamic and static libpng and zlib libraries
+# used below may change in later releases of the libraries.  This makefile
+# builds both statically and dynamically linked executables by default.
+# (You need only one set, but for testing it can be handy to have both.)
+
+
+# macros --------------------------------------------------------------------
+
+#PNGDIR = ../..#                for libpng-x.y.z/contrib/gregbook builds
+PNGDIR = ../libpng-win32
+PNGINC = -I$(PNGDIR)
+PNGLIBd = $(PNGDIR)/libpng.dll.a        # dynamically linked
+PNGLIBs = $(PNGDIR)/libpng.a            # statically linked, local libpng
+
+#ZDIR = ../../../zlib-win32#    for libpng-x.y.z/contrib/gregbook builds
+ZDIR = ../zlib-win32
+ZINC = -I$(ZDIR)
+ZLIBd = $(ZDIR)/libzdll.a
+ZLIBs = $(ZDIR)/libz.a
+
+# change this to be the path where mingw32 installs its stuff:
+W32DIR =
+#W32DIR = /usr/local/cross-tools/i386-mingw32msvc
+W32INC = -I$(W32DIR)/include
+W32LIB = $(W32DIR)/lib/libuser32.a $(W32DIR)/lib/libgdi32.a
+
+CC = gcc
+#CC = i386-mingw32msvc-gcc #    e.g., Linux -> Win32 cross-compilation
+LD = $(CC)
+RM = rm -f
+CFLAGS = -O -Wall $(INCS) $(MINGW_CCFLAGS)
+# [note that -Wall is a gcc-specific compilation flag ("most warnings on")]
+# [-ansi, -pedantic and -W can also be used]
+LDFLAGS = $(MINGW_LDFLAGS)
+O = .o
+E = .exe
+
+INCS = $(PNGINC) $(ZINC) $(W32INC)
+RLIBSd = $(PNGLIBd) $(ZLIBd) $(W32LIB) -lm
+RLIBSs = $(PNGLIBs) $(ZLIBs) $(W32LIB) -lm
+WLIBSd = $(PNGLIBd) $(ZLIBd)
+WLIBSs = $(PNGLIBs) $(ZLIBs)
+
+RPNG   = rpng-win
+RPNG2  = rpng2-win
+WPNG   = wpng
+
+ROBJSd  = $(RPNG)$(O) readpng.pic$(O)
+ROBJS2d = $(RPNG2)$(O) readpng2.pic$(O)
+WOBJSd  = $(WPNG)$(O) writepng.pic$(O)
+
+RPNGs  = $(RPNG)-static
+RPNG2s = $(RPNG2)-static
+WPNGs  = $(WPNG)-static
+
+ROBJSs  = $(RPNG)$(O) readpng$(O)
+ROBJS2s = $(RPNG2)$(O) readpng2$(O)
+WOBJSs  = $(WPNG)$(O) writepng$(O)
+
+STATIC_EXES  = $(RPNGs)$(E) $(RPNG2s)$(E) $(WPNGs)$(E)
+DYNAMIC_EXES = $(RPNG)$(E) $(RPNG2)$(E) $(WPNG)$(E)
+
+EXES = $(STATIC_EXES) $(DYNAMIC_EXES)
+
+
+# implicit make rules -------------------------------------------------------
+
+.c$(O):
+        $(CC) -c $(CFLAGS) $<
+
+%.pic$(O): %.c
+        $(CC) -c $(CFLAGS) -DPNG_BUILD_DLL -o $@ $<
+
+
+# dependencies --------------------------------------------------------------
+
+all:  $(EXES)
+
+$(RPNGs)$(E): $(ROBJSs)
+        $(LD) $(LDFLAGS) -o $@ $(ROBJSs) $(RLIBSs)
+
+$(RPNG)$(E): $(ROBJSd)
+        $(LD) $(LDFLAGS) -o $@ $(ROBJSd) $(RLIBSd)
+
+$(RPNG2s)$(E): $(ROBJS2s)
+        $(LD) $(LDFLAGS) -o $@ $(ROBJS2s) $(RLIBSs)
+
+$(RPNG2)$(E): $(ROBJS2d)
+        $(LD) $(LDFLAGS) -o $@ $(ROBJS2d) $(RLIBSd)
+
+$(WPNGs)$(E): $(WOBJSs)
+        $(LD) $(LDFLAGS) -o $@ $(WOBJSs) $(WLIBSs)
+
+$(WPNG)$(E): $(WOBJSd)
+        $(LD) $(LDFLAGS) -o $@ $(WOBJSd) $(WLIBSd)
+
+$(RPNG)$(O):    $(RPNG).c readpng.h
+$(RPNG2)$(O):   $(RPNG2).c readpng2.h
+$(WPNG)$(O):    $(WPNG).c writepng.h
+
+readpng$(O) readpng.pic$(O):    readpng.c readpng.h
+readpng2$(O) readpng2.pic$(O):  readpng2.c readpng2.h
+writepng$(O) writepng.pic$(O):  writepng.c writepng.h
+
+
+# maintenance ---------------------------------------------------------------
+
+clean:
+        $(RM) $(EXES)
+        $(RM) $(ROBJSs) $(ROBJS2s) $(WOBJSs)
+        $(RM) $(ROBJSd) $(ROBJS2d) $(WOBJSd)
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/Makefile.sgi b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/Makefile.sgi
index 8773a00..91623ac 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/Makefile.sgi
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/Makefile.sgi
@@ -1,104 +1,104 @@
-# Sample makefile for rpng-x / rpng2-x / wpng for SGI using cc and make.

-# Greg Roelofs

-# Last modified:  7 March 2002

-#

-#       The programs built by this makefile are described in the book,

-#       "PNG:  The Definitive Guide," by Greg Roelofs (O'Reilly and

-#       Associates, 1999).  Go buy a copy, eh?  Buy some for friends

-#       and family, too.  (Not that this is a blatant plug or anything.)

-#

-# Invoke this makefile from a shell prompt in the usual way; for example:

-#

-#       make -f Makefile.sgi

-#

-# This makefile assumes libpng and zlib have already been built or downloaded

-# and are both installed in /usr/local/{include,lib} (as indicated by the

-# PNG* and Z* macros below).  Edit as appropriate--choose only ONE each of

-# the PNGINC, PNGLIB, ZINC and ZLIB lines.

-#

-# This makefile builds dynamically linked executables (against libpng and zlib,

-# that is), but that can be changed by uncommenting the appropriate PNGLIB and

-# ZLIB lines.

-

-

-# macros --------------------------------------------------------------------

-

-PNGINC = -I/usr/local/include/libpng15

-PNGLIB = -L/usr/local/lib -lpng15         # dynamically linked against libpng

-#PNGLIB = /usr/local/lib/libpng15.a # statically linked against libpng

-# or:

-#PNGINC = -I../..

-#PNGLIB = -L../.. -lpng

-#PNGLIB = ../../libpng.a

-

-ZINC = -I/usr/local/include

-ZLIB = -L/usr/local/lib -lz             # dynamically linked against zlib

-#ZLIB = /usr/local/lib/libz.a           # statically linked against zlib

-#ZINC = -I../zlib

-#ZLIB = -L../zlib -lz

-#ZLIB = ../../../zlib/libz.a

-

-XINC = -I/usr/include/X11               # old-style, stock X distributions

-XLIB = -L/usr/lib/X11 -lX11

-#XINC = -I/usr/openwin/include          # Sun workstations (OpenWindows)

-#XLIB = -L/usr/openwin/lib -lX11

-#XINC = -I/usr/X11R6/include            # new X distributions (XFree86, etc.)

-#XLIB = -L/usr/X11R6/lib -lX11

-

-INCS = $(PNGINC) $(ZINC) $(XINC)

-RLIBS = $(PNGLIB) $(ZLIB) $(XLIB) -lm

-WLIBS = $(PNGLIB) $(ZLIB)

-

-CC = cc

-LD = cc

-RM = rm -f

-# ABI must be the same as that used to build libpng.

-ABI=

-CFLAGS = $(ABI) -O -fullwarn $(INCS)

-LDFLAGS = $(ABI)

-O = .o

-E =

-

-RPNG  = rpng-x

-RPNG2 = rpng2-x

-WPNG  = wpng

-

-ROBJS  = $(RPNG)$(O) readpng$(O)

-ROBJS2 = $(RPNG2)$(O) readpng2$(O)

-WOBJS  = $(WPNG)$(O) writepng$(O)

-

-EXES = $(RPNG)$(E) $(RPNG2)$(E) $(WPNG)$(E)

-

-

-# implicit make rules -------------------------------------------------------

-

-.c$(O):

-        $(CC) -c $(CFLAGS) $<

-

-

-# dependencies --------------------------------------------------------------

-

-all:  $(EXES)

-

-$(RPNG)$(E): $(ROBJS)

-        $(LD) $(LDFLAGS) -o $@ $(ROBJS) $(RLIBS)

-

-$(RPNG2)$(E): $(ROBJS2)

-        $(LD) $(LDFLAGS) -o $@ $(ROBJS2) $(RLIBS)

-

-$(WPNG)$(E): $(WOBJS)

-        $(LD) $(LDFLAGS) -o $@ $(WOBJS) $(WLIBS)

-

-$(RPNG)$(O):    $(RPNG).c readpng.h

-$(RPNG2)$(O):   $(RPNG2).c readpng2.h

-$(WPNG)$(O):    $(WPNG).c writepng.h

-

-readpng$(O):    readpng.c readpng.h

-readpng2$(O):   readpng2.c readpng2.h

-writepng$(O):   writepng.c writepng.h

-

-

-# maintenance ---------------------------------------------------------------

-

-clean:

-        $(RM) $(EXES) $(ROBJS) $(ROBJS2) $(WOBJS)

+# Sample makefile for rpng-x / rpng2-x / wpng for SGI using cc and make.
+# Greg Roelofs
+# Last modified:  7 March 2002
+#
+#       The programs built by this makefile are described in the book,
+#       "PNG:  The Definitive Guide," by Greg Roelofs (O'Reilly and
+#       Associates, 1999).  Go buy a copy, eh?  Buy some for friends
+#       and family, too.  (Not that this is a blatant plug or anything.)
+#
+# Invoke this makefile from a shell prompt in the usual way; for example:
+#
+#       make -f Makefile.sgi
+#
+# This makefile assumes libpng and zlib have already been built or downloaded
+# and are both installed in /usr/local/{include,lib} (as indicated by the
+# PNG* and Z* macros below).  Edit as appropriate--choose only ONE each of
+# the PNGINC, PNGLIB, ZINC and ZLIB lines.
+#
+# This makefile builds dynamically linked executables (against libpng and zlib,
+# that is), but that can be changed by uncommenting the appropriate PNGLIB and
+# ZLIB lines.
+
+
+# macros --------------------------------------------------------------------
+
+PNGINC = -I/usr/local/include/libpng15
+PNGLIB = -L/usr/local/lib -lpng15         # dynamically linked against libpng
+#PNGLIB = /usr/local/lib/libpng15.a # statically linked against libpng
+# or:
+#PNGINC = -I../..
+#PNGLIB = -L../.. -lpng
+#PNGLIB = ../../libpng.a
+
+ZINC = -I/usr/local/include
+ZLIB = -L/usr/local/lib -lz             # dynamically linked against zlib
+#ZLIB = /usr/local/lib/libz.a           # statically linked against zlib
+#ZINC = -I../zlib
+#ZLIB = -L../zlib -lz
+#ZLIB = ../../../zlib/libz.a
+
+XINC = -I/usr/include/X11               # old-style, stock X distributions
+XLIB = -L/usr/lib/X11 -lX11
+#XINC = -I/usr/openwin/include          # Sun workstations (OpenWindows)
+#XLIB = -L/usr/openwin/lib -lX11
+#XINC = -I/usr/X11R6/include            # new X distributions (XFree86, etc.)
+#XLIB = -L/usr/X11R6/lib -lX11
+
+INCS = $(PNGINC) $(ZINC) $(XINC)
+RLIBS = $(PNGLIB) $(ZLIB) $(XLIB) -lm
+WLIBS = $(PNGLIB) $(ZLIB)
+
+CC = cc
+LD = cc
+RM = rm -f
+# ABI must be the same as that used to build libpng.
+ABI=
+CFLAGS = $(ABI) -O -fullwarn $(INCS)
+LDFLAGS = $(ABI)
+O = .o
+E =
+
+RPNG  = rpng-x
+RPNG2 = rpng2-x
+WPNG  = wpng
+
+ROBJS  = $(RPNG)$(O) readpng$(O)
+ROBJS2 = $(RPNG2)$(O) readpng2$(O)
+WOBJS  = $(WPNG)$(O) writepng$(O)
+
+EXES = $(RPNG)$(E) $(RPNG2)$(E) $(WPNG)$(E)
+
+
+# implicit make rules -------------------------------------------------------
+
+.c$(O):
+        $(CC) -c $(CFLAGS) $<
+
+
+# dependencies --------------------------------------------------------------
+
+all:  $(EXES)
+
+$(RPNG)$(E): $(ROBJS)
+        $(LD) $(LDFLAGS) -o $@ $(ROBJS) $(RLIBS)
+
+$(RPNG2)$(E): $(ROBJS2)
+        $(LD) $(LDFLAGS) -o $@ $(ROBJS2) $(RLIBS)
+
+$(WPNG)$(E): $(WOBJS)
+        $(LD) $(LDFLAGS) -o $@ $(WOBJS) $(WLIBS)
+
+$(RPNG)$(O):    $(RPNG).c readpng.h
+$(RPNG2)$(O):   $(RPNG2).c readpng2.h
+$(WPNG)$(O):    $(WPNG).c writepng.h
+
+readpng$(O):    readpng.c readpng.h
+readpng2$(O):   readpng2.c readpng2.h
+writepng$(O):   writepng.c writepng.h
+
+
+# maintenance ---------------------------------------------------------------
+
+clean:
+        $(RM) $(EXES) $(ROBJS) $(ROBJS2) $(WOBJS)
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/Makefile.unx b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/Makefile.unx
index 3bffc2f..b52d8b6 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/Makefile.unx
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/Makefile.unx
@@ -1,132 +1,132 @@
-# Sample makefile for rpng-x / rpng2-x / wpng using gcc and make.

-# Greg Roelofs

-# Last modified:  2 June 2007

-#

-#       The programs built by this makefile are described in the book,

-#       "PNG:  The Definitive Guide," by Greg Roelofs (O'Reilly and

-#       Associates, 1999).  Go buy a copy, eh?  Well, OK, it's not

-#       generally for sale anymore, but it's the thought that counts,

-#       right?  (Hint:  http://www.libpng.org/pub/png/book/ )

-#

-# Invoke this makefile from a shell prompt in the usual way; for example:

-#

-#       make -f Makefile.unx

-#

-# This makefile assumes libpng and zlib have already been built or downloaded

-# and are installed in /usr/local/{include,lib} or as otherwise indicated by

-# the PNG* and Z* macros below.  Edit as appropriate--choose only ONE each of

-# the PNGINC, PNGLIBd, PNGLIBs, ZINC, ZLIBd and ZLIBs lines.

-#

-# This makefile builds both dynamically and statically linked executables

-# (against libpng and zlib, that is), but that can be changed by modifying

-# the "EXES =" line.  (You need only one set, but for testing it can be handy

-# to have both.)

-

-

-# macros --------------------------------------------------------------------

-

-#PNGDIR = /usr/local/lib

-#PNGINC = -I/usr/local/include/libpng15

-#PNGLIBd = -L$(PNGDIR) -lpng15 # dynamically linked, installed libpng

-#PNGLIBs = $(PNGDIR)/libpng15.a # statically linked, installed libpng

-# or:

-PNGDIR = ../..# this one is for libpng-x.y.z/contrib/gregbook builds

-#PNGDIR = ../libpng

-PNGINC = -I$(PNGDIR)

-PNGLIBd = -Wl,-rpath,$(PNGDIR) -L$(PNGDIR) -lpng15      # dynamically linked

-PNGLIBs = $(PNGDIR)/libpng.a            # statically linked, local libpng

-

-ZDIR = /usr/local/lib

-#ZDIR = /usr/lib64

-ZINC = -I/usr/local/include

-ZLIBd = -L$(ZDIR) -lz                   # dynamically linked against zlib

-ZLIBs = $(ZDIR)/libz.a                  # statically linked against zlib

-# or:

-#ZDIR = ../zlib

-#ZINC = -I$(ZDIR)

-#ZLIBd = -Wl,-rpath,$(ZDIR) -L$(ZDIR) -lz  # -rpath allows in-place testing

-#ZLIBs = $(ZDIR)/libz.a

-

-#XINC = -I/usr/include                  # old-style, stock X distributions

-#XLIB = -L/usr/lib/X11 -lX11            #  (including SGI IRIX)

-#XINC = -I/usr/openwin/include          # Sun workstations (OpenWindows)

-#XLIB = -L/usr/openwin/lib -lX11

-XINC = -I/usr/X11R6/include             # new X distributions (X.org, etc.)

-XLIB = -L/usr/X11R6/lib -lX11

-#XLIB = -L/usr/X11R6/lib64 -lX11        # e.g., Red Hat on AMD64

-

-INCS = $(PNGINC) $(ZINC) $(XINC)

-RLIBSd = $(PNGLIBd) $(ZLIBd) $(XLIB) -lm

-RLIBSs = $(PNGLIBs) $(ZLIBs) $(XLIB) -lm

-WLIBSd = $(PNGLIBd) $(ZLIBd) -lm

-WLIBSs = $(PNGLIBs) $(ZLIBs)

-

-CC = gcc

-LD = gcc

-RM = rm -f

-CFLAGS = -O -Wall $(INCS) -DFEATURE_LOOP

-# [note that -Wall is a gcc-specific compilation flag ("most warnings on")]

-# [-ansi, -pedantic and -W can also be used]

-LDFLAGS =

-O = .o

-E =

-

-RPNG   = rpng-x

-RPNG2  = rpng2-x

-WPNG   = wpng

-

-RPNGs  = $(RPNG)-static

-RPNG2s = $(RPNG2)-static

-WPNGs  = $(WPNG)-static

-

-ROBJS  = $(RPNG)$(O) readpng$(O)

-ROBJS2 = $(RPNG2)$(O) readpng2$(O)

-WOBJS  = $(WPNG)$(O) writepng$(O)

-

-STATIC_EXES  = $(RPNGs)$(E) $(RPNG2s)$(E) $(WPNGs)$(E)

-DYNAMIC_EXES = $(RPNG)$(E) $(RPNG2)$(E) $(WPNG)$(E)

-

-EXES = $(STATIC_EXES) $(DYNAMIC_EXES)

-

-

-# implicit make rules -------------------------------------------------------

-

-.c$(O):

-        $(CC) -c $(CFLAGS) $<

-

-

-# dependencies --------------------------------------------------------------

-

-all:  $(EXES)

-

-$(RPNGs)$(E): $(ROBJS)

-        $(LD) $(LDFLAGS) -o $@ $(ROBJS) $(RLIBSs)

-

-$(RPNG)$(E): $(ROBJS)

-        $(LD) $(LDFLAGS) -o $@ $(ROBJS) $(RLIBSd)

-

-$(RPNG2s)$(E): $(ROBJS2)

-        $(LD) $(LDFLAGS) -o $@ $(ROBJS2) $(RLIBSs)

-

-$(RPNG2)$(E): $(ROBJS2)

-        $(LD) $(LDFLAGS) -o $@ $(ROBJS2) $(RLIBSd)

-

-$(WPNGs)$(E): $(WOBJS)

-        $(LD) $(LDFLAGS) -o $@ $(WOBJS) $(WLIBSs)

-

-$(WPNG)$(E): $(WOBJS)

-        $(LD) $(LDFLAGS) -o $@ $(WOBJS) $(WLIBSd)

-

-$(RPNG)$(O):    $(RPNG).c readpng.h

-$(RPNG2)$(O):   $(RPNG2).c readpng2.h

-$(WPNG)$(O):    $(WPNG).c writepng.h

-

-readpng$(O):    readpng.c readpng.h

-readpng2$(O):   readpng2.c readpng2.h

-writepng$(O):   writepng.c writepng.h

-

-

-# maintenance ---------------------------------------------------------------

-

-clean:

-        $(RM) $(EXES) $(ROBJS) $(ROBJS2) $(WOBJS)

+# Sample makefile for rpng-x / rpng2-x / wpng using gcc and make.
+# Greg Roelofs
+# Last modified:  2 June 2007
+#
+#       The programs built by this makefile are described in the book,
+#       "PNG:  The Definitive Guide," by Greg Roelofs (O'Reilly and
+#       Associates, 1999).  Go buy a copy, eh?  Well, OK, it's not
+#       generally for sale anymore, but it's the thought that counts,
+#       right?  (Hint:  http://www.libpng.org/pub/png/book/ )
+#
+# Invoke this makefile from a shell prompt in the usual way; for example:
+#
+#       make -f Makefile.unx
+#
+# This makefile assumes libpng and zlib have already been built or downloaded
+# and are installed in /usr/local/{include,lib} or as otherwise indicated by
+# the PNG* and Z* macros below.  Edit as appropriate--choose only ONE each of
+# the PNGINC, PNGLIBd, PNGLIBs, ZINC, ZLIBd and ZLIBs lines.
+#
+# This makefile builds both dynamically and statically linked executables
+# (against libpng and zlib, that is), but that can be changed by modifying
+# the "EXES =" line.  (You need only one set, but for testing it can be handy
+# to have both.)
+
+
+# macros --------------------------------------------------------------------
+
+#PNGDIR = /usr/local/lib
+#PNGINC = -I/usr/local/include/libpng15
+#PNGLIBd = -L$(PNGDIR) -lpng15 # dynamically linked, installed libpng
+#PNGLIBs = $(PNGDIR)/libpng15.a # statically linked, installed libpng
+# or:
+PNGDIR = ../..# this one is for libpng-x.y.z/contrib/gregbook builds
+#PNGDIR = ../libpng
+PNGINC = -I$(PNGDIR)
+PNGLIBd = -Wl,-rpath,$(PNGDIR) -L$(PNGDIR) -lpng15      # dynamically linked
+PNGLIBs = $(PNGDIR)/libpng.a            # statically linked, local libpng
+
+ZDIR = /usr/local/lib
+#ZDIR = /usr/lib64
+ZINC = -I/usr/local/include
+ZLIBd = -L$(ZDIR) -lz                   # dynamically linked against zlib
+ZLIBs = $(ZDIR)/libz.a                  # statically linked against zlib
+# or:
+#ZDIR = ../zlib
+#ZINC = -I$(ZDIR)
+#ZLIBd = -Wl,-rpath,$(ZDIR) -L$(ZDIR) -lz  # -rpath allows in-place testing
+#ZLIBs = $(ZDIR)/libz.a
+
+#XINC = -I/usr/include                  # old-style, stock X distributions
+#XLIB = -L/usr/lib/X11 -lX11            #  (including SGI IRIX)
+#XINC = -I/usr/openwin/include          # Sun workstations (OpenWindows)
+#XLIB = -L/usr/openwin/lib -lX11
+XINC = -I/usr/X11R6/include             # new X distributions (X.org, etc.)
+XLIB = -L/usr/X11R6/lib -lX11
+#XLIB = -L/usr/X11R6/lib64 -lX11        # e.g., Red Hat on AMD64
+
+INCS = $(PNGINC) $(ZINC) $(XINC)
+RLIBSd = $(PNGLIBd) $(ZLIBd) $(XLIB) -lm
+RLIBSs = $(PNGLIBs) $(ZLIBs) $(XLIB) -lm
+WLIBSd = $(PNGLIBd) $(ZLIBd) -lm
+WLIBSs = $(PNGLIBs) $(ZLIBs)
+
+CC = gcc
+LD = gcc
+RM = rm -f
+CFLAGS = -O -Wall $(INCS) -DFEATURE_LOOP
+# [note that -Wall is a gcc-specific compilation flag ("most warnings on")]
+# [-ansi, -pedantic and -W can also be used]
+LDFLAGS =
+O = .o
+E =
+
+RPNG   = rpng-x
+RPNG2  = rpng2-x
+WPNG   = wpng
+
+RPNGs  = $(RPNG)-static
+RPNG2s = $(RPNG2)-static
+WPNGs  = $(WPNG)-static
+
+ROBJS  = $(RPNG)$(O) readpng$(O)
+ROBJS2 = $(RPNG2)$(O) readpng2$(O)
+WOBJS  = $(WPNG)$(O) writepng$(O)
+
+STATIC_EXES  = $(RPNGs)$(E) $(RPNG2s)$(E) $(WPNGs)$(E)
+DYNAMIC_EXES = $(RPNG)$(E) $(RPNG2)$(E) $(WPNG)$(E)
+
+EXES = $(STATIC_EXES) $(DYNAMIC_EXES)
+
+
+# implicit make rules -------------------------------------------------------
+
+.c$(O):
+        $(CC) -c $(CFLAGS) $<
+
+
+# dependencies --------------------------------------------------------------
+
+all:  $(EXES)
+
+$(RPNGs)$(E): $(ROBJS)
+        $(LD) $(LDFLAGS) -o $@ $(ROBJS) $(RLIBSs)
+
+$(RPNG)$(E): $(ROBJS)
+        $(LD) $(LDFLAGS) -o $@ $(ROBJS) $(RLIBSd)
+
+$(RPNG2s)$(E): $(ROBJS2)
+        $(LD) $(LDFLAGS) -o $@ $(ROBJS2) $(RLIBSs)
+
+$(RPNG2)$(E): $(ROBJS2)
+        $(LD) $(LDFLAGS) -o $@ $(ROBJS2) $(RLIBSd)
+
+$(WPNGs)$(E): $(WOBJS)
+        $(LD) $(LDFLAGS) -o $@ $(WOBJS) $(WLIBSs)
+
+$(WPNG)$(E): $(WOBJS)
+        $(LD) $(LDFLAGS) -o $@ $(WOBJS) $(WLIBSd)
+
+$(RPNG)$(O):    $(RPNG).c readpng.h
+$(RPNG2)$(O):   $(RPNG2).c readpng2.h
+$(WPNG)$(O):    $(WPNG).c writepng.h
+
+readpng$(O):    readpng.c readpng.h
+readpng2$(O):   readpng2.c readpng2.h
+writepng$(O):   writepng.c writepng.h
+
+
+# maintenance ---------------------------------------------------------------
+
+clean:
+        $(RM) $(EXES) $(ROBJS) $(ROBJS2) $(WOBJS)
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/Makefile.w32 b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/Makefile.w32
index eced083..41cfb23 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/Makefile.w32
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/Makefile.w32
@@ -1,113 +1,113 @@
-# Sample makefile for rpng-win / rpng2-win / wpng using MSVC and NMAKE.

-# Greg Roelofs

-# Last modified:  2 June 2007

-#

-#       The programs built by this makefile are described in the book,

-#       "PNG:  The Definitive Guide," by Greg Roelofs (O'Reilly and

-#       Associates, 1999).  Go buy a copy, eh?  Well, OK, it's not

-#       generally for sale anymore, but it's the thought that counts,

-#       right?  (Hint:  http://www.libpng.org/pub/png/book/ )

-#

-# Invoke this makefile from a DOS prompt window via:

-#

-#       %devstudio%\vc\bin\vcvars32.bat

-#       nmake -nologo -f Makefile.w32

-#

-# where %devstudio% is the installation directory for MSVC / DevStudio.  If

-# you get "environment out of space" errors, create a desktop shortcut with

-# "c:\windows\command.com /e:4096" as the program command line and set the

-# working directory to this directory.  Then double-click to open the new

-# DOS-prompt window with a bigger environment and retry the commands above.

-#

-# This makefile assumes libpng and zlib have already been built or downloaded

-# and are in subdirectories at the same level as the current subdirectory

-# (as indicated by the PNGPATH and ZPATH macros below).  Edit as appropriate.

-#

-# Note that the names of the dynamic and static libpng and zlib libraries

-# used below may change in later releases of the libraries.  This makefile

-# builds statically linked executables, but that can be changed by uncom-

-# menting the appropriate PNGLIB and ZLIB lines.

-

-!include <ntwin32.mak>

-

-

-# macros --------------------------------------------------------------------

-

-PNGPATH = ../libpng

-PNGINC = -I$(PNGPATH)

-#PNGLIB = $(PNGPATH)/pngdll.lib

-PNGLIB = $(PNGPATH)/libpng.lib

-

-ZPATH = ../zlib

-ZINC = -I$(ZPATH)

-#ZLIB = $(ZPATH)/zlibdll.lib

-ZLIB = $(ZPATH)/zlibstat.lib

-

-WINLIBS = -defaultlib:user32.lib gdi32.lib

-# ["real" apps may also need comctl32.lib, comdlg32.lib, winmm.lib, etc.]

-

-INCS = $(PNGINC) $(ZINC)

-RLIBS = $(PNGLIB) $(ZLIB) $(WINLIBS)

-WLIBS = $(PNGLIB) $(ZLIB)

-

-CC = cl

-LD = link

-RM = del

-CFLAGS = -nologo -O -W3 $(INCS) $(cvars)

-# [note that -W3 is an MSVC-specific compilation flag ("all warnings on")]

-# [see %devstudio%\vc\include\win32.mak for cvars macro definition]

-O = .obj

-E = .exe

-

-RLDFLAGS = -nologo -subsystem:windows

-WLDFLAGS = -nologo

-

-RPNG  = rpng-win

-RPNG2 = rpng2-win

-WPNG  = wpng

-

-ROBJS  = $(RPNG)$(O) readpng$(O)

-ROBJS2 = $(RPNG2)$(O) readpng2$(O)

-WOBJS  = $(WPNG)$(O) writepng$(O)

-

-EXES = $(RPNG)$(E) $(RPNG2)$(E) $(WPNG)$(E)

-

-

-# implicit make rules -------------------------------------------------------

-

-.c$(O):

-        $(CC) -c $(CFLAGS) $<

-

-

-# dependencies --------------------------------------------------------------

-

-all:  $(EXES)

-

-$(RPNG)$(E): $(ROBJS)

-        $(LD) $(RLDFLAGS) -out:$@ $(ROBJS) $(RLIBS)

-

-$(RPNG2)$(E): $(ROBJS2)

-        $(LD) $(RLDFLAGS) -out:$@ $(ROBJS2) $(RLIBS)

-

-$(WPNG)$(E): $(WOBJS)

-        $(LD) $(WLDFLAGS) -out:$@ $(WOBJS) $(WLIBS)

-

-$(RPNG)$(O):    $(RPNG).c readpng.h

-$(RPNG2)$(O):   $(RPNG2).c readpng2.h

-$(WPNG)$(O):    $(WPNG).c writepng.h

-

-readpng$(O):    readpng.c readpng.h

-readpng2$(O):   readpng2.c readpng2.h

-writepng$(O):   writepng.c writepng.h

-

-

-# maintenance ---------------------------------------------------------------

-

-clean:

-#       ideally we could just do this:

-#       $(RM) $(EXES) $(ROBJS) $(ROBJS2) $(WOBJS)

-#       ...but the Windows "DEL" command is none too bright, so:

-        $(RM) r*$(E)

-        $(RM) w*$(E)

-        $(RM) r*$(O)

-        $(RM) w*$(O)

+# Sample makefile for rpng-win / rpng2-win / wpng using MSVC and NMAKE.
+# Greg Roelofs
+# Last modified:  2 June 2007
+#
+#       The programs built by this makefile are described in the book,
+#       "PNG:  The Definitive Guide," by Greg Roelofs (O'Reilly and
+#       Associates, 1999).  Go buy a copy, eh?  Well, OK, it's not
+#       generally for sale anymore, but it's the thought that counts,
+#       right?  (Hint:  http://www.libpng.org/pub/png/book/ )
+#
+# Invoke this makefile from a DOS prompt window via:
+#
+#       %devstudio%\vc\bin\vcvars32.bat
+#       nmake -nologo -f Makefile.w32
+#
+# where %devstudio% is the installation directory for MSVC / DevStudio.  If
+# you get "environment out of space" errors, create a desktop shortcut with
+# "c:\windows\command.com /e:4096" as the program command line and set the
+# working directory to this directory.  Then double-click to open the new
+# DOS-prompt window with a bigger environment and retry the commands above.
+#
+# This makefile assumes libpng and zlib have already been built or downloaded
+# and are in subdirectories at the same level as the current subdirectory
+# (as indicated by the PNGPATH and ZPATH macros below).  Edit as appropriate.
+#
+# Note that the names of the dynamic and static libpng and zlib libraries
+# used below may change in later releases of the libraries.  This makefile
+# builds statically linked executables, but that can be changed by uncom-
+# menting the appropriate PNGLIB and ZLIB lines.
+
+!include <ntwin32.mak>
+
+
+# macros --------------------------------------------------------------------
+
+PNGPATH = ../libpng
+PNGINC = -I$(PNGPATH)
+#PNGLIB = $(PNGPATH)/pngdll.lib
+PNGLIB = $(PNGPATH)/libpng.lib
+
+ZPATH = ../zlib
+ZINC = -I$(ZPATH)
+#ZLIB = $(ZPATH)/zlibdll.lib
+ZLIB = $(ZPATH)/zlibstat.lib
+
+WINLIBS = -defaultlib:user32.lib gdi32.lib
+# ["real" apps may also need comctl32.lib, comdlg32.lib, winmm.lib, etc.]
+
+INCS = $(PNGINC) $(ZINC)
+RLIBS = $(PNGLIB) $(ZLIB) $(WINLIBS)
+WLIBS = $(PNGLIB) $(ZLIB)
+
+CC = cl
+LD = link
+RM = del
+CFLAGS = -nologo -O -W3 $(INCS) $(cvars)
+# [note that -W3 is an MSVC-specific compilation flag ("all warnings on")]
+# [see %devstudio%\vc\include\win32.mak for cvars macro definition]
+O = .obj
+E = .exe
+
+RLDFLAGS = -nologo -subsystem:windows
+WLDFLAGS = -nologo
+
+RPNG  = rpng-win
+RPNG2 = rpng2-win
+WPNG  = wpng
+
+ROBJS  = $(RPNG)$(O) readpng$(O)
+ROBJS2 = $(RPNG2)$(O) readpng2$(O)
+WOBJS  = $(WPNG)$(O) writepng$(O)
+
+EXES = $(RPNG)$(E) $(RPNG2)$(E) $(WPNG)$(E)
+
+
+# implicit make rules -------------------------------------------------------
+
+.c$(O):
+        $(CC) -c $(CFLAGS) $<
+
+
+# dependencies --------------------------------------------------------------
+
+all:  $(EXES)
+
+$(RPNG)$(E): $(ROBJS)
+        $(LD) $(RLDFLAGS) -out:$@ $(ROBJS) $(RLIBS)
+
+$(RPNG2)$(E): $(ROBJS2)
+        $(LD) $(RLDFLAGS) -out:$@ $(ROBJS2) $(RLIBS)
+
+$(WPNG)$(E): $(WOBJS)
+        $(LD) $(WLDFLAGS) -out:$@ $(WOBJS) $(WLIBS)
+
+$(RPNG)$(O):    $(RPNG).c readpng.h
+$(RPNG2)$(O):   $(RPNG2).c readpng2.h
+$(WPNG)$(O):    $(WPNG).c writepng.h
+
+readpng$(O):    readpng.c readpng.h
+readpng2$(O):   readpng2.c readpng2.h
+writepng$(O):   writepng.c writepng.h
+
+
+# maintenance ---------------------------------------------------------------
+
+clean:
+#       ideally we could just do this:
+#       $(RM) $(EXES) $(ROBJS) $(ROBJS2) $(WOBJS)
+#       ...but the Windows "DEL" command is none too bright, so:
+        $(RM) r*$(E)
+        $(RM) w*$(E)
+        $(RM) r*$(O)
+        $(RM) w*$(O)
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/README b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/README
index 791fec8..7b1f6a3 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/README
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/README
@@ -1,186 +1,186 @@
-                     ===========================

-                      PNG: The Definitive Guide

-                     ===========================

-

-                             Source Code

-

-Chapters 13, 14 and 15 of "PNG: The Definitive Guide" discuss three free,

-cross-platform demo programs that show how to use the libpng reference

-library:  rpng, rpng2 and wpng.  rpng and rpng2 are viewers; the first is

-a very simple example that that shows how a standard file-viewer might use

-libpng, while the second is designed to process streaming data and shows

-how a web browser might be written.  wpng is a simple command-line program

-that reads binary PGM and PPM files (the ``raw'' grayscale and RGB subsets

-of PBMPLUS/NetPBM) and converts them to PNG.

-

-The source code for all three demo programs currently compiles under

-Unix, OpenVMS, and 32-bit Windows.  (Special thanks to Martin Zinser,

-zinser@decus.de, for making the necessary changes for OpenVMS and for

-providing an appropriate build script.)  Build instructions can be found

-below.

-

-Files:

-

-   README             this file

-   LICENSE            terms of distribution and reuse (BSD-like or GNU GPL)

-   COPYING            GNU General Public License (GPL)

-

-   Makefile.unx       Unix makefile

-   Makefile.w32       Windows (MSVC) makefile

-   makevms.com        OpenVMS build script

-

-   rpng-win.c         Windows front end for the basic viewer

-   rpng-x.c           X Window System (Unix, OpenVMS) front end

-   readpng.c          generic back end for the basic viewer

-   readpng.h          header file for the basic viewer

-

-   rpng2-win.c        Windows front end for the progressive viewer

-   rpng2-x.c          X front end for the progressive viewer

-   readpng2.c         generic back end for the progressive viewer

-   readpng2.h         header file for the progressive viewer

-

-   wpng.c             generic (text) front end for the converter

-   writepng.c         generic back end for the converter

-   writepng.h         header file for the converter

-

-   toucan.png         transparent PNG for testing (by Stefan Schneider)

-

-Note that, although the programs are designed to be functional, their

-primary purpose is to illustrate how to use libpng to add PNG support to

-other programs.  As such, their user interfaces are crude and definitely

-are not intended for everyday use.

-

-Please see http://www.libpng.org/pub/png/pngbook.html for further infor-

-mation and links to the latest version of the source code, and Chapters

-13-15 of the book for detailed discussion of the three programs.

-

-Greg Roelofs

-http://pobox.com/~newt/greg_contact.html

-16 March 2008

-

-

-BUILD INSTRUCTIONS

-

- - Prerequisites (in order of compilation):

-

-      - zlib            http://zlib.net/

-      - libpng          http://www.libpng.org/pub/png/libpng.html

-      - pngbook         http://www.libpng.org/pub/png/book/sources.html

-

-     The pngbook demo programs are explicitly designed to demonstrate proper

-     coding techniques for using the libpng reference library.  As a result,

-     you need to download and build both zlib (on which libpng depends) and

-     libpng.  A common build setup is to place the zlib, libpng and pngbook

-     subdirectory trees ("folders") in the same parent directory.  Then the

-     libpng build can refer to files in ../zlib (or ..\zlib or [-.zlib]),

-     and similarly for the pngbook build.

-

-     Note that all three packages are designed to be built from a command

-     line by default; those who wish to use a graphical or other integrated

-     development environments are on their own.

-

-

- - Unix:

-

-     Unpack the latest pngbook sources (which should correspond to this

-     README file) into a directory and change into that directory.

-

-     Copy Makefile.unx to Makefile and edit the PNG* and Z* variables

-     appropriately (possibly also the X* variables if necessary).

-

-     make

-

-     There is no "install" target, so copy the three executables somewhere

-     in your path or run them from the current directory.  All three will

-     print a basic usage screen when run without any command-line arguments;

-     see the book for more details.

-

-

- - Windows:

-

-     Unpack the latest pngbook sources (which should correspond to this

-     README file) into a folder, open a "DOS shell" or "command prompt"

-     or equivalent command-line window, and cd into the folder where you

-     unpacked the source code.

-

-     For MSVC, set up the necessary environment variables by invoking

-

-        %devstudio%\vc\bin\vcvars32.bat

-

-     where where %devstudio% is the installation directory for MSVC /

-     DevStudio.  If you get "environment out of space" errors under 95/98,

-     create a desktop shortcut with "c:\windows\command.com /e:4096" as

-     the program command line and set the working directory to the pngbook

-     directory.  Then double-click to open the new DOS-prompt window with

-     a bigger environment and retry the commands above.

-

-     Copy Makefile.w32 to Makefile and edit the PNGPATH and ZPATH variables

-     appropriately (possibly also the "INC" and "LIB" variables if needed).

-     Note that the names of the dynamic and static libpng and zlib libraries

-     used in the makefile may change in later releases of the libraries.

-     Also note that, as of libpng version 1.0.5, MSVC DLL builds do not work.

-     This makefile therefore builds statically linked executables, but if

-     the DLL problems ever get fixed, uncommenting the appropriate PNGLIB

-     and ZLIB lines will build dynamically linked executables instead.

-

-     Do the build by typing

-

-        nmake

-

-     The result should be three executables:  rpng-win.exe, rpng2-win.exe,

-     and wpng.exe.  Copy them somewhere in your PATH or run them from the

-     current folder.  Like the Unix versions, the two windowed programs

-     (rpng and rpng2) now display a usage screen in a console window when

-     invoked without command-line arguments; this is new behavior as of

-     the June 2001 release.  Note that the programs use the Unix-style "-"

-     character to specify options, instead of the more common DOS/Windows

-     "/" character.  (For example:  "rpng2-win -bgpat 4 foo.png", not

-     "rpng2-win /bgpat 4 foo.png")

-

-

- - OpenVMS:

-

-     Unpack the pngbook sources into a subdirectory and change into that

-     subdirectory.

-

-     Edit makevms.com appropriately, specifically the zpath and pngpath

-     variables.

-

-     @makevms

-

-     To run the programs, they probably first need to be set up as "foreign

-     symbols," with "disk" and "dir" set appropriately:

-

-     $ rpng  == "$disk:[dir]rpng-x.exe"

-     $ rpng2 == "$disk:[dir]rpng2-x.exe"

-     $ wpng  == "$disk:[dir]wpng.exe"

-

-     All three will print a basic usage screen when run without any command-

-     line arguments; see the book for more details.  Note that the options

-     style is Unix-like, i.e., preceded by "-" rather than "/".

-

-

-RUNNING THE PROGRAMS:  (VERY) BRIEF INTRO

-

-     rpng is a simple PNG viewer that can display transparent PNGs with a

-     specified background color; for example,

-

-        rpng -bgcolor \#ff0000 toucan.png

-

-     would display the image with a red background.  rpng2 is a progressive

-     viewer that simulates a web browser in some respects; it can display

-     images against either a background color or a dynamically generated

-     background image.  For example:

-

-        rpng2 -bgpat 16 toucan.png

-

-     wpng is a purely command-line image converter from binary PBMPLUS/NetPBM

-     format (.pgm or .ppm) to PNG; for example,

-

-        wpng -time < toucan-notrans.ppm > toucan-notrans.png

-

-     would convert the specified PPM file (using redirection) to PNG, auto-

-     matically setting the PNG modification-time chunk.

-

-     All options can be abbreviated to the shortest unique value; for example,

-     "-bgc" for -bgcolor (versus "-bgp" for -bgpat), or "-g" for -gamma.

+                     ===========================
+                      PNG: The Definitive Guide
+                     ===========================
+
+                             Source Code
+
+Chapters 13, 14 and 15 of "PNG: The Definitive Guide" discuss three free,
+cross-platform demo programs that show how to use the libpng reference
+library:  rpng, rpng2 and wpng.  rpng and rpng2 are viewers; the first is
+a very simple example that that shows how a standard file-viewer might use
+libpng, while the second is designed to process streaming data and shows
+how a web browser might be written.  wpng is a simple command-line program
+that reads binary PGM and PPM files (the ``raw'' grayscale and RGB subsets
+of PBMPLUS/NetPBM) and converts them to PNG.
+
+The source code for all three demo programs currently compiles under
+Unix, OpenVMS, and 32-bit Windows.  (Special thanks to Martin Zinser,
+zinser@decus.de, for making the necessary changes for OpenVMS and for
+providing an appropriate build script.)  Build instructions can be found
+below.
+
+Files:
+
+   README             this file
+   LICENSE            terms of distribution and reuse (BSD-like or GNU GPL)
+   COPYING            GNU General Public License (GPL)
+
+   Makefile.unx       Unix makefile
+   Makefile.w32       Windows (MSVC) makefile
+   makevms.com        OpenVMS build script
+
+   rpng-win.c         Windows front end for the basic viewer
+   rpng-x.c           X Window System (Unix, OpenVMS) front end
+   readpng.c          generic back end for the basic viewer
+   readpng.h          header file for the basic viewer
+
+   rpng2-win.c        Windows front end for the progressive viewer
+   rpng2-x.c          X front end for the progressive viewer
+   readpng2.c         generic back end for the progressive viewer
+   readpng2.h         header file for the progressive viewer
+
+   wpng.c             generic (text) front end for the converter
+   writepng.c         generic back end for the converter
+   writepng.h         header file for the converter
+
+   toucan.png         transparent PNG for testing (by Stefan Schneider)
+
+Note that, although the programs are designed to be functional, their
+primary purpose is to illustrate how to use libpng to add PNG support to
+other programs.  As such, their user interfaces are crude and definitely
+are not intended for everyday use.
+
+Please see http://www.libpng.org/pub/png/pngbook.html for further infor-
+mation and links to the latest version of the source code, and Chapters
+13-15 of the book for detailed discussion of the three programs.
+
+Greg Roelofs
+http://pobox.com/~newt/greg_contact.html
+16 March 2008
+
+
+BUILD INSTRUCTIONS
+
+ - Prerequisites (in order of compilation):
+
+      - zlib            http://zlib.net/
+      - libpng          http://www.libpng.org/pub/png/libpng.html
+      - pngbook         http://www.libpng.org/pub/png/book/sources.html
+
+     The pngbook demo programs are explicitly designed to demonstrate proper
+     coding techniques for using the libpng reference library.  As a result,
+     you need to download and build both zlib (on which libpng depends) and
+     libpng.  A common build setup is to place the zlib, libpng and pngbook
+     subdirectory trees ("folders") in the same parent directory.  Then the
+     libpng build can refer to files in ../zlib (or ..\zlib or [-.zlib]),
+     and similarly for the pngbook build.
+
+     Note that all three packages are designed to be built from a command
+     line by default; those who wish to use a graphical or other integrated
+     development environments are on their own.
+
+
+ - Unix:
+
+     Unpack the latest pngbook sources (which should correspond to this
+     README file) into a directory and change into that directory.
+
+     Copy Makefile.unx to Makefile and edit the PNG* and Z* variables
+     appropriately (possibly also the X* variables if necessary).
+
+     make
+
+     There is no "install" target, so copy the three executables somewhere
+     in your path or run them from the current directory.  All three will
+     print a basic usage screen when run without any command-line arguments;
+     see the book for more details.
+
+
+ - Windows:
+
+     Unpack the latest pngbook sources (which should correspond to this
+     README file) into a folder, open a "DOS shell" or "command prompt"
+     or equivalent command-line window, and cd into the folder where you
+     unpacked the source code.
+
+     For MSVC, set up the necessary environment variables by invoking
+
+        %devstudio%\vc\bin\vcvars32.bat
+
+     where where %devstudio% is the installation directory for MSVC /
+     DevStudio.  If you get "environment out of space" errors under 95/98,
+     create a desktop shortcut with "c:\windows\command.com /e:4096" as
+     the program command line and set the working directory to the pngbook
+     directory.  Then double-click to open the new DOS-prompt window with
+     a bigger environment and retry the commands above.
+
+     Copy Makefile.w32 to Makefile and edit the PNGPATH and ZPATH variables
+     appropriately (possibly also the "INC" and "LIB" variables if needed).
+     Note that the names of the dynamic and static libpng and zlib libraries
+     used in the makefile may change in later releases of the libraries.
+     Also note that, as of libpng version 1.0.5, MSVC DLL builds do not work.
+     This makefile therefore builds statically linked executables, but if
+     the DLL problems ever get fixed, uncommenting the appropriate PNGLIB
+     and ZLIB lines will build dynamically linked executables instead.
+
+     Do the build by typing
+
+        nmake
+
+     The result should be three executables:  rpng-win.exe, rpng2-win.exe,
+     and wpng.exe.  Copy them somewhere in your PATH or run them from the
+     current folder.  Like the Unix versions, the two windowed programs
+     (rpng and rpng2) now display a usage screen in a console window when
+     invoked without command-line arguments; this is new behavior as of
+     the June 2001 release.  Note that the programs use the Unix-style "-"
+     character to specify options, instead of the more common DOS/Windows
+     "/" character.  (For example:  "rpng2-win -bgpat 4 foo.png", not
+     "rpng2-win /bgpat 4 foo.png")
+
+
+ - OpenVMS:
+
+     Unpack the pngbook sources into a subdirectory and change into that
+     subdirectory.
+
+     Edit makevms.com appropriately, specifically the zpath and pngpath
+     variables.
+
+     @makevms
+
+     To run the programs, they probably first need to be set up as "foreign
+     symbols," with "disk" and "dir" set appropriately:
+
+     $ rpng  == "$disk:[dir]rpng-x.exe"
+     $ rpng2 == "$disk:[dir]rpng2-x.exe"
+     $ wpng  == "$disk:[dir]wpng.exe"
+
+     All three will print a basic usage screen when run without any command-
+     line arguments; see the book for more details.  Note that the options
+     style is Unix-like, i.e., preceded by "-" rather than "/".
+
+
+RUNNING THE PROGRAMS:  (VERY) BRIEF INTRO
+
+     rpng is a simple PNG viewer that can display transparent PNGs with a
+     specified background color; for example,
+
+        rpng -bgcolor \#ff0000 toucan.png
+
+     would display the image with a red background.  rpng2 is a progressive
+     viewer that simulates a web browser in some respects; it can display
+     images against either a background color or a dynamically generated
+     background image.  For example:
+
+        rpng2 -bgpat 16 toucan.png
+
+     wpng is a purely command-line image converter from binary PBMPLUS/NetPBM
+     format (.pgm or .ppm) to PNG; for example,
+
+        wpng -time < toucan-notrans.ppm > toucan-notrans.png
+
+     would convert the specified PPM file (using redirection) to PNG, auto-
+     matically setting the PNG modification-time chunk.
+
+     All options can be abbreviated to the shortest unique value; for example,
+     "-bgc" for -bgcolor (versus "-bgp" for -bgpat), or "-g" for -gamma.
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/makevms.com b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/makevms.com
index 29a5727..f32bcab 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/makevms.com
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/makevms.com
@@ -1,132 +1,132 @@
-$!------------------------------------------------------------------------------

-$! make "PNG: The Definitive Guide" demo programs (for X) under OpenVMS

-$!

-$! Script created by Martin Zinser for libpng; modified by Greg Roelofs

-$! for standalone pngbook source distribution.

-$!

-$!

-$!    Set locations where zlib and libpng sources live.

-$!

-$ zpath   = ""

-$ pngpath = ""

-$!

-$ if f$search("[---.zlib]zlib.h").nes."" then zpath = "[---.zlib]"

-$ if f$search("[--]png.h").nes."" then pngpath = "[--]"

-$!

-$ if f$search("[-.zlib]zlib.h").nes."" then zpath = "[-.zlib]"

-$ if f$search("[-.libpng]png.h").nes."" then pngpath = "[-.libpng]"

-$!

-$ if zpath .eqs. ""

-$ then

-$   write sys$output "zlib include not found. Exiting..."

-$   exit 2

-$ endif

-$!

-$ if pngpath .eqs. ""

-$ then

-$   write sys$output "libpng include not found. Exiting..."

-$   exit 2

-$ endif

-$!

-$!    Look for the compiler used.

-$!

-$ ccopt="/include=(''zpath',''pngpath')"

-$ if f$getsyi("HW_MODEL").ge.1024

-$ then

-$  ccopt = "/prefix=all"+ccopt

-$  comp  = "__decc__=1"

-$  if f$trnlnm("SYS").eqs."" then define sys sys$library:

-$ else

-$  if f$search("SYS$SYSTEM:DECC$COMPILER.EXE").eqs.""

-$   then

-$    if f$trnlnm("SYS").eqs."" then define sys sys$library:

-$    if f$search("SYS$SYSTEM:VAXC.EXE").eqs.""

-$     then

-$      comp  = "__gcc__=1"

-$      CC :== GCC

-$     else

-$      comp = "__vaxc__=1"

-$     endif

-$   else

-$    if f$trnlnm("SYS").eqs."" then define sys decc$library_include:

-$    ccopt = "/decc/prefix=all"+ccopt

-$    comp  = "__decc__=1"

-$  endif

-$ endif

-$ open/write lopt lib.opt

-$ write lopt "''pngpath'libpng.olb/lib"

-$ write lopt "''zpath'libz.olb/lib"

-$ close lopt

-$ open/write xopt x11.opt

-$ write xopt "sys$library:decw$xlibshr.exe/share"

-$ close xopt

-$!

-$!    Build 'em.

-$!

-$ write sys$output "Compiling PNG book programs ..."

-$   CALL MAKE readpng.OBJ "cc ''CCOPT' readpng" -

-        readpng.c readpng.h

-$   CALL MAKE readpng2.OBJ "cc ''CCOPT' readpng2" -

-        readpng2.c readpng2.h

-$   CALL MAKE writepng.OBJ "cc ''CCOPT' writepng" -

-        writepng.c writepng.h

-$   write sys$output "Building rpng-x..."

-$   CALL MAKE rpng-x.OBJ "cc ''CCOPT' rpng-x" -

-        rpng-x.c readpng.h

-$   call make rpng-x.exe -

-        "LINK rpng-x,readpng,lib.opt/opt,x11.opt/opt" -

-        rpng-x.obj readpng.obj

-$   write sys$output "Building rpng2-x..."

-$   CALL MAKE rpng2-x.OBJ "cc ''CCOPT' rpng2-x" -

-        rpng2-x.c readpng2.h

-$   call make rpng2-x.exe -

-        "LINK rpng2-x,readpng2,lib.opt/opt,x11.opt/opt" -

-        rpng2-x.obj readpng2.obj

-$   write sys$output "Building wpng..."

-$   CALL MAKE wpng.OBJ "cc ''CCOPT' wpng" -

-        wpng.c writepng.h

-$   call make wpng.exe -

-        "LINK wpng,writepng,lib.opt/opt" -

-        wpng.obj writepng.obj

-$ exit

-$!

-$!

-$MAKE: SUBROUTINE   !SUBROUTINE TO CHECK DEPENDENCIES

-$ V = 'F$Verify(0)

-$! P1 = What we are trying to make

-$! P2 = Command to make it

-$! P3 - P8  What it depends on

-$

-$ If F$Search(P1) .Eqs. "" Then Goto Makeit

-$ Time = F$CvTime(F$File(P1,"RDT"))

-$arg=3

-$Loop:

-$       Argument = P'arg

-$       If Argument .Eqs. "" Then Goto Exit

-$       El=0

-$Loop2:

-$       File = F$Element(El," ",Argument)

-$       If File .Eqs. " " Then Goto Endl

-$       AFile = ""

-$Loop3:

-$       OFile = AFile

-$       AFile = F$Search(File)

-$       If AFile .Eqs. "" .Or. AFile .Eqs. OFile Then Goto NextEl

-$       If F$CvTime(F$File(AFile,"RDT")) .Ges. Time Then Goto Makeit

-$       Goto Loop3

-$NextEL:

-$       El = El + 1

-$       Goto Loop2

-$EndL:

-$ arg=arg+1

-$ If arg .Le. 8 Then Goto Loop

-$ Goto Exit

-$

-$Makeit:

-$ VV=F$VERIFY(0)

-$ write sys$output P2

-$ 'P2

-$ VV='F$Verify(VV)

-$Exit:

-$ If V Then Set Verify

-$ENDSUBROUTINE

+$!------------------------------------------------------------------------------
+$! make "PNG: The Definitive Guide" demo programs (for X) under OpenVMS
+$!
+$! Script created by Martin Zinser for libpng; modified by Greg Roelofs
+$! for standalone pngbook source distribution.
+$!
+$!
+$!    Set locations where zlib and libpng sources live.
+$!
+$ zpath   = ""
+$ pngpath = ""
+$!
+$ if f$search("[---.zlib]zlib.h").nes."" then zpath = "[---.zlib]"
+$ if f$search("[--]png.h").nes."" then pngpath = "[--]"
+$!
+$ if f$search("[-.zlib]zlib.h").nes."" then zpath = "[-.zlib]"
+$ if f$search("[-.libpng]png.h").nes."" then pngpath = "[-.libpng]"
+$!
+$ if zpath .eqs. ""
+$ then
+$   write sys$output "zlib include not found. Exiting..."
+$   exit 2
+$ endif
+$!
+$ if pngpath .eqs. ""
+$ then
+$   write sys$output "libpng include not found. Exiting..."
+$   exit 2
+$ endif
+$!
+$!    Look for the compiler used.
+$!
+$ ccopt="/include=(''zpath',''pngpath')"
+$ if f$getsyi("HW_MODEL").ge.1024
+$ then
+$  ccopt = "/prefix=all"+ccopt
+$  comp  = "__decc__=1"
+$  if f$trnlnm("SYS").eqs."" then define sys sys$library:
+$ else
+$  if f$search("SYS$SYSTEM:DECC$COMPILER.EXE").eqs.""
+$   then
+$    if f$trnlnm("SYS").eqs."" then define sys sys$library:
+$    if f$search("SYS$SYSTEM:VAXC.EXE").eqs.""
+$     then
+$      comp  = "__gcc__=1"
+$      CC :== GCC
+$     else
+$      comp = "__vaxc__=1"
+$     endif
+$   else
+$    if f$trnlnm("SYS").eqs."" then define sys decc$library_include:
+$    ccopt = "/decc/prefix=all"+ccopt
+$    comp  = "__decc__=1"
+$  endif
+$ endif
+$ open/write lopt lib.opt
+$ write lopt "''pngpath'libpng.olb/lib"
+$ write lopt "''zpath'libz.olb/lib"
+$ close lopt
+$ open/write xopt x11.opt
+$ write xopt "sys$library:decw$xlibshr.exe/share"
+$ close xopt
+$!
+$!    Build 'em.
+$!
+$ write sys$output "Compiling PNG book programs ..."
+$   CALL MAKE readpng.OBJ "cc ''CCOPT' readpng" -
+        readpng.c readpng.h
+$   CALL MAKE readpng2.OBJ "cc ''CCOPT' readpng2" -
+        readpng2.c readpng2.h
+$   CALL MAKE writepng.OBJ "cc ''CCOPT' writepng" -
+        writepng.c writepng.h
+$   write sys$output "Building rpng-x..."
+$   CALL MAKE rpng-x.OBJ "cc ''CCOPT' rpng-x" -
+        rpng-x.c readpng.h
+$   call make rpng-x.exe -
+        "LINK rpng-x,readpng,lib.opt/opt,x11.opt/opt" -
+        rpng-x.obj readpng.obj
+$   write sys$output "Building rpng2-x..."
+$   CALL MAKE rpng2-x.OBJ "cc ''CCOPT' rpng2-x" -
+        rpng2-x.c readpng2.h
+$   call make rpng2-x.exe -
+        "LINK rpng2-x,readpng2,lib.opt/opt,x11.opt/opt" -
+        rpng2-x.obj readpng2.obj
+$   write sys$output "Building wpng..."
+$   CALL MAKE wpng.OBJ "cc ''CCOPT' wpng" -
+        wpng.c writepng.h
+$   call make wpng.exe -
+        "LINK wpng,writepng,lib.opt/opt" -
+        wpng.obj writepng.obj
+$ exit
+$!
+$!
+$MAKE: SUBROUTINE   !SUBROUTINE TO CHECK DEPENDENCIES
+$ V = 'F$Verify(0)
+$! P1 = What we are trying to make
+$! P2 = Command to make it
+$! P3 - P8  What it depends on
+$
+$ If F$Search(P1) .Eqs. "" Then Goto Makeit
+$ Time = F$CvTime(F$File(P1,"RDT"))
+$arg=3
+$Loop:
+$       Argument = P'arg
+$       If Argument .Eqs. "" Then Goto Exit
+$       El=0
+$Loop2:
+$       File = F$Element(El," ",Argument)
+$       If File .Eqs. " " Then Goto Endl
+$       AFile = ""
+$Loop3:
+$       OFile = AFile
+$       AFile = F$Search(File)
+$       If AFile .Eqs. "" .Or. AFile .Eqs. OFile Then Goto NextEl
+$       If F$CvTime(F$File(AFile,"RDT")) .Ges. Time Then Goto Makeit
+$       Goto Loop3
+$NextEL:
+$       El = El + 1
+$       Goto Loop2
+$EndL:
+$ arg=arg+1
+$ If arg .Le. 8 Then Goto Loop
+$ Goto Exit
+$
+$Makeit:
+$ VV=F$VERIFY(0)
+$ write sys$output P2
+$ 'P2
+$ VV='F$Verify(VV)
+$Exit:
+$ If V Then Set Verify
+$ENDSUBROUTINE
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/readpng.c b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/readpng.c
index 27a2f11..df42c30 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/readpng.c
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/readpng.c
@@ -1,311 +1,311 @@
-/*---------------------------------------------------------------------------

-

-   rpng - simple PNG display program                              readpng.c

-

-  ---------------------------------------------------------------------------

-

-      Copyright (c) 1998-2007 Greg Roelofs.  All rights reserved.

-

-      This software is provided "as is," without warranty of any kind,

-      express or implied.  In no event shall the author or contributors

-      be held liable for any damages arising in any way from the use of

-      this software.

-

-      The contents of this file are DUAL-LICENSED.  You may modify and/or

-      redistribute this software according to the terms of one of the

-      following two licenses (at your option):

-

-

-      LICENSE 1 ("BSD-like with advertising clause"):

-

-      Permission is granted to anyone to use this software for any purpose,

-      including commercial applications, and to alter it and redistribute

-      it freely, subject to the following restrictions:

-

-      1. Redistributions of source code must retain the above copyright

-         notice, disclaimer, and this list of conditions.

-      2. Redistributions in binary form must reproduce the above copyright

-         notice, disclaimer, and this list of conditions in the documenta-

-         tion and/or other materials provided with the distribution.

-      3. All advertising materials mentioning features or use of this

-         software must display the following acknowledgment:

-

-            This product includes software developed by Greg Roelofs

-            and contributors for the book, "PNG: The Definitive Guide,"

-            published by O'Reilly and Associates.

-

-

-      LICENSE 2 (GNU GPL v2 or later):

-

-      This program is free software; you can redistribute it and/or modify

-      it under the terms of the GNU General Public License as published by

-      the Free Software Foundation; either version 2 of the License, or

-      (at your option) any later version.

-

-      This program is distributed in the hope that it will be useful,

-      but WITHOUT ANY WARRANTY; without even the implied warranty of

-      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

-      GNU General Public License for more details.

-

-      You should have received a copy of the GNU General Public License

-      along with this program; if not, write to the Free Software Foundation,

-      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

-

-  ---------------------------------------------------------------------------*/

-

-#include <stdio.h>

-#include <stdlib.h>

-

-#include "png.h"        /* libpng header; includes zlib.h */

-#include "readpng.h"    /* typedefs, common macros, public prototypes */

-

-/* future versions of libpng will provide this macro: */

-#ifndef png_jmpbuf

-#  define png_jmpbuf(png_ptr)   ((png_ptr)->jmpbuf)

-#endif

-

-

-static png_structp png_ptr = NULL;

-static png_infop info_ptr = NULL;

-

-png_uint_32  width, height;

-int  bit_depth, color_type;

-uch  *image_data = NULL;

-

-

-void readpng_version_info(void)

-{

-    fprintf(stderr, "   Compiled with libpng %s; using libpng %s.\n",

-      PNG_LIBPNG_VER_STRING, png_libpng_ver);

-    fprintf(stderr, "   Compiled with zlib %s; using zlib %s.\n",

-      ZLIB_VERSION, zlib_version);

-}

-

-

-/* return value = 0 for success, 1 for bad sig, 2 for bad IHDR, 4 for no mem */

-

-int readpng_init(FILE *infile, ulg *pWidth, ulg *pHeight)

-{

-    uch sig[8];

-

-

-    /* first do a quick check that the file really is a PNG image; could

-     * have used slightly more general png_sig_cmp() function instead */

-

-    fread(sig, 1, 8, infile);

-    if (png_sig_cmp(sig, 0, 8))

-        return 1;   /* bad signature */

-

-

-    /* could pass pointers to user-defined error handlers instead of NULLs: */

-

-    png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);

-    if (!png_ptr)

-        return 4;   /* out of memory */

-

-    info_ptr = png_create_info_struct(png_ptr);

-    if (!info_ptr) {

-        png_destroy_read_struct(&png_ptr, NULL, NULL);

-        return 4;   /* out of memory */

-    }

-

-

-    /* we could create a second info struct here (end_info), but it's only

-     * useful if we want to keep pre- and post-IDAT chunk info separated

-     * (mainly for PNG-aware image editors and converters) */

-

-

-    /* setjmp() must be called in every function that calls a PNG-reading

-     * libpng function */

-

-    if (setjmp(png_jmpbuf(png_ptr))) {

-        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);

-        return 2;

-    }

-

-

-    png_init_io(png_ptr, infile);

-    png_set_sig_bytes(png_ptr, 8);  /* we already read the 8 signature bytes */

-

-    png_read_info(png_ptr, info_ptr);  /* read all PNG info up to image data */

-

-

-    /* alternatively, could make separate calls to png_get_image_width(),

-     * etc., but want bit_depth and color_type for later [don't care about

-     * compression_type and filter_type => NULLs] */

-

-    png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,

-      NULL, NULL, NULL);

-    *pWidth = width;

-    *pHeight = height;

-

-

-    /* OK, that's all we need for now; return happy */

-

-    return 0;

-}

-

-

-

-

-/* returns 0 if succeeds, 1 if fails due to no bKGD chunk, 2 if libpng error;

- * scales values to 8-bit if necessary */

-

-int readpng_get_bgcolor(uch *red, uch *green, uch *blue)

-{

-    png_color_16p pBackground;

-

-

-    /* setjmp() must be called in every function that calls a PNG-reading

-     * libpng function */

-

-    if (setjmp(png_jmpbuf(png_ptr))) {

-        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);

-        return 2;

-    }

-

-

-    if (!png_get_valid(png_ptr, info_ptr, PNG_INFO_bKGD))

-        return 1;

-

-    /* it is not obvious from the libpng documentation, but this function

-     * takes a pointer to a pointer, and it always returns valid red, green

-     * and blue values, regardless of color_type: */

-

-    png_get_bKGD(png_ptr, info_ptr, &pBackground);

-

-

-    /* however, it always returns the raw bKGD data, regardless of any

-     * bit-depth transformations, so check depth and adjust if necessary */

-

-    if (bit_depth == 16) {

-        *red   = pBackground->red   >> 8;

-        *green = pBackground->green >> 8;

-        *blue  = pBackground->blue  >> 8;

-    } else if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8) {

-        if (bit_depth == 1)

-            *red = *green = *blue = pBackground->gray? 255 : 0;

-        else if (bit_depth == 2)

-            *red = *green = *blue = (255/3) * pBackground->gray;

-        else /* bit_depth == 4 */

-            *red = *green = *blue = (255/15) * pBackground->gray;

-    } else {

-        *red   = (uch)pBackground->red;

-        *green = (uch)pBackground->green;

-        *blue  = (uch)pBackground->blue;

-    }

-

-    return 0;

-}

-

-

-

-

-/* display_exponent == LUT_exponent * CRT_exponent */

-

-uch *readpng_get_image(double display_exponent, int *pChannels, ulg *pRowbytes)

-{

-    double  gamma;

-    png_uint_32  i, rowbytes;

-    png_bytepp  row_pointers = NULL;

-

-

-    /* setjmp() must be called in every function that calls a PNG-reading

-     * libpng function */

-

-    if (setjmp(png_jmpbuf(png_ptr))) {

-        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);

-        return NULL;

-    }

-

-

-    /* expand palette images to RGB, low-bit-depth grayscale images to 8 bits,

-     * transparency chunks to full alpha channel; strip 16-bit-per-sample

-     * images to 8 bits per sample; and convert grayscale to RGB[A] */

-

-    if (color_type == PNG_COLOR_TYPE_PALETTE)

-        png_set_expand(png_ptr);

-    if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)

-        png_set_expand(png_ptr);

-    if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))

-        png_set_expand(png_ptr);

-#ifdef PNG_READ_16_TO_8_SUPPORTED

-    if (bit_depth == 16)

-#  ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED

-        png_set_scale_16(png_ptr);

-#  else

-        png_set_strip_16(png_ptr);

-#  endif

-#endif

-    if (color_type == PNG_COLOR_TYPE_GRAY ||

-        color_type == PNG_COLOR_TYPE_GRAY_ALPHA)

-        png_set_gray_to_rgb(png_ptr);

-

-

-    /* unlike the example in the libpng documentation, we have *no* idea where

-     * this file may have come from--so if it doesn't have a file gamma, don't

-     * do any correction ("do no harm") */

-

-    if (png_get_gAMA(png_ptr, info_ptr, &gamma))

-        png_set_gamma(png_ptr, display_exponent, gamma);

-

-

-    /* all transformations have been registered; now update info_ptr data,

-     * get rowbytes and channels, and allocate image memory */

-

-    png_read_update_info(png_ptr, info_ptr);

-

-    *pRowbytes = rowbytes = png_get_rowbytes(png_ptr, info_ptr);

-    *pChannels = (int)png_get_channels(png_ptr, info_ptr);

-

-    if ((image_data = (uch *)malloc(rowbytes*height)) == NULL) {

-        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);

-        return NULL;

-    }

-    if ((row_pointers = (png_bytepp)malloc(height*sizeof(png_bytep))) == NULL) {

-        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);

-        free(image_data);

-        image_data = NULL;

-        return NULL;

-    }

-

-    Trace((stderr, "readpng_get_image:  channels = %d, rowbytes = %ld, height = %ld\n",

-        *pChannels, rowbytes, height));

-

-

-    /* set the individual row_pointers to point at the correct offsets */

-

-    for (i = 0;  i < height;  ++i)

-        row_pointers[i] = image_data + i*rowbytes;

-

-

-    /* now we can go ahead and just read the whole image */

-

-    png_read_image(png_ptr, row_pointers);

-

-

-    /* and we're done!  (png_read_end() can be omitted if no processing of

-     * post-IDAT text/time/etc. is desired) */

-

-    free(row_pointers);

-    row_pointers = NULL;

-

-    png_read_end(png_ptr, NULL);

-

-    return image_data;

-}

-

-

-void readpng_cleanup(int free_image_data)

-{

-    if (free_image_data && image_data) {

-        free(image_data);

-        image_data = NULL;

-    }

-

-    if (png_ptr && info_ptr) {

-        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);

-        png_ptr = NULL;

-        info_ptr = NULL;

-    }

-}

+/*---------------------------------------------------------------------------
+
+   rpng - simple PNG display program                              readpng.c
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-2007 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      The contents of this file are DUAL-LICENSED.  You may modify and/or
+      redistribute this software according to the terms of one of the
+      following two licenses (at your option):
+
+
+      LICENSE 1 ("BSD-like with advertising clause"):
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+
+      LICENSE 2 (GNU GPL v2 or later):
+
+      This program is free software; you can redistribute it and/or modify
+      it under the terms of the GNU General Public License as published by
+      the Free Software Foundation; either version 2 of the License, or
+      (at your option) any later version.
+
+      This program is distributed in the hope that it will be useful,
+      but WITHOUT ANY WARRANTY; without even the implied warranty of
+      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+      GNU General Public License for more details.
+
+      You should have received a copy of the GNU General Public License
+      along with this program; if not, write to the Free Software Foundation,
+      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+  ---------------------------------------------------------------------------*/
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "png.h"        /* libpng header; includes zlib.h */
+#include "readpng.h"    /* typedefs, common macros, public prototypes */
+
+/* future versions of libpng will provide this macro: */
+#ifndef png_jmpbuf
+#  define png_jmpbuf(png_ptr)   ((png_ptr)->jmpbuf)
+#endif
+
+
+static png_structp png_ptr = NULL;
+static png_infop info_ptr = NULL;
+
+png_uint_32  width, height;
+int  bit_depth, color_type;
+uch  *image_data = NULL;
+
+
+void readpng_version_info(void)
+{
+    fprintf(stderr, "   Compiled with libpng %s; using libpng %s.\n",
+      PNG_LIBPNG_VER_STRING, png_libpng_ver);
+    fprintf(stderr, "   Compiled with zlib %s; using zlib %s.\n",
+      ZLIB_VERSION, zlib_version);
+}
+
+
+/* return value = 0 for success, 1 for bad sig, 2 for bad IHDR, 4 for no mem */
+
+int readpng_init(FILE *infile, ulg *pWidth, ulg *pHeight)
+{
+    uch sig[8];
+
+
+    /* first do a quick check that the file really is a PNG image; could
+     * have used slightly more general png_sig_cmp() function instead */
+
+    fread(sig, 1, 8, infile);
+    if (png_sig_cmp(sig, 0, 8))
+        return 1;   /* bad signature */
+
+
+    /* could pass pointers to user-defined error handlers instead of NULLs: */
+
+    png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+    if (!png_ptr)
+        return 4;   /* out of memory */
+
+    info_ptr = png_create_info_struct(png_ptr);
+    if (!info_ptr) {
+        png_destroy_read_struct(&png_ptr, NULL, NULL);
+        return 4;   /* out of memory */
+    }
+
+
+    /* we could create a second info struct here (end_info), but it's only
+     * useful if we want to keep pre- and post-IDAT chunk info separated
+     * (mainly for PNG-aware image editors and converters) */
+
+
+    /* setjmp() must be called in every function that calls a PNG-reading
+     * libpng function */
+
+    if (setjmp(png_jmpbuf(png_ptr))) {
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+        return 2;
+    }
+
+
+    png_init_io(png_ptr, infile);
+    png_set_sig_bytes(png_ptr, 8);  /* we already read the 8 signature bytes */
+
+    png_read_info(png_ptr, info_ptr);  /* read all PNG info up to image data */
+
+
+    /* alternatively, could make separate calls to png_get_image_width(),
+     * etc., but want bit_depth and color_type for later [don't care about
+     * compression_type and filter_type => NULLs] */
+
+    png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
+      NULL, NULL, NULL);
+    *pWidth = width;
+    *pHeight = height;
+
+
+    /* OK, that's all we need for now; return happy */
+
+    return 0;
+}
+
+
+
+
+/* returns 0 if succeeds, 1 if fails due to no bKGD chunk, 2 if libpng error;
+ * scales values to 8-bit if necessary */
+
+int readpng_get_bgcolor(uch *red, uch *green, uch *blue)
+{
+    png_color_16p pBackground;
+
+
+    /* setjmp() must be called in every function that calls a PNG-reading
+     * libpng function */
+
+    if (setjmp(png_jmpbuf(png_ptr))) {
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+        return 2;
+    }
+
+
+    if (!png_get_valid(png_ptr, info_ptr, PNG_INFO_bKGD))
+        return 1;
+
+    /* it is not obvious from the libpng documentation, but this function
+     * takes a pointer to a pointer, and it always returns valid red, green
+     * and blue values, regardless of color_type: */
+
+    png_get_bKGD(png_ptr, info_ptr, &pBackground);
+
+
+    /* however, it always returns the raw bKGD data, regardless of any
+     * bit-depth transformations, so check depth and adjust if necessary */
+
+    if (bit_depth == 16) {
+        *red   = pBackground->red   >> 8;
+        *green = pBackground->green >> 8;
+        *blue  = pBackground->blue  >> 8;
+    } else if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8) {
+        if (bit_depth == 1)
+            *red = *green = *blue = pBackground->gray? 255 : 0;
+        else if (bit_depth == 2)
+            *red = *green = *blue = (255/3) * pBackground->gray;
+        else /* bit_depth == 4 */
+            *red = *green = *blue = (255/15) * pBackground->gray;
+    } else {
+        *red   = (uch)pBackground->red;
+        *green = (uch)pBackground->green;
+        *blue  = (uch)pBackground->blue;
+    }
+
+    return 0;
+}
+
+
+
+
+/* display_exponent == LUT_exponent * CRT_exponent */
+
+uch *readpng_get_image(double display_exponent, int *pChannels, ulg *pRowbytes)
+{
+    double  gamma;
+    png_uint_32  i, rowbytes;
+    png_bytepp  row_pointers = NULL;
+
+
+    /* setjmp() must be called in every function that calls a PNG-reading
+     * libpng function */
+
+    if (setjmp(png_jmpbuf(png_ptr))) {
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+        return NULL;
+    }
+
+
+    /* expand palette images to RGB, low-bit-depth grayscale images to 8 bits,
+     * transparency chunks to full alpha channel; strip 16-bit-per-sample
+     * images to 8 bits per sample; and convert grayscale to RGB[A] */
+
+    if (color_type == PNG_COLOR_TYPE_PALETTE)
+        png_set_expand(png_ptr);
+    if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
+        png_set_expand(png_ptr);
+    if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))
+        png_set_expand(png_ptr);
+#ifdef PNG_READ_16_TO_8_SUPPORTED
+    if (bit_depth == 16)
+#  ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
+        png_set_scale_16(png_ptr);
+#  else
+        png_set_strip_16(png_ptr);
+#  endif
+#endif
+    if (color_type == PNG_COLOR_TYPE_GRAY ||
+        color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+        png_set_gray_to_rgb(png_ptr);
+
+
+    /* unlike the example in the libpng documentation, we have *no* idea where
+     * this file may have come from--so if it doesn't have a file gamma, don't
+     * do any correction ("do no harm") */
+
+    if (png_get_gAMA(png_ptr, info_ptr, &gamma))
+        png_set_gamma(png_ptr, display_exponent, gamma);
+
+
+    /* all transformations have been registered; now update info_ptr data,
+     * get rowbytes and channels, and allocate image memory */
+
+    png_read_update_info(png_ptr, info_ptr);
+
+    *pRowbytes = rowbytes = png_get_rowbytes(png_ptr, info_ptr);
+    *pChannels = (int)png_get_channels(png_ptr, info_ptr);
+
+    if ((image_data = (uch *)malloc(rowbytes*height)) == NULL) {
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+        return NULL;
+    }
+    if ((row_pointers = (png_bytepp)malloc(height*sizeof(png_bytep))) == NULL) {
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+        free(image_data);
+        image_data = NULL;
+        return NULL;
+    }
+
+    Trace((stderr, "readpng_get_image:  channels = %d, rowbytes = %ld, height = %ld\n",
+        *pChannels, rowbytes, height));
+
+
+    /* set the individual row_pointers to point at the correct offsets */
+
+    for (i = 0;  i < height;  ++i)
+        row_pointers[i] = image_data + i*rowbytes;
+
+
+    /* now we can go ahead and just read the whole image */
+
+    png_read_image(png_ptr, row_pointers);
+
+
+    /* and we're done!  (png_read_end() can be omitted if no processing of
+     * post-IDAT text/time/etc. is desired) */
+
+    free(row_pointers);
+    row_pointers = NULL;
+
+    png_read_end(png_ptr, NULL);
+
+    return image_data;
+}
+
+
+void readpng_cleanup(int free_image_data)
+{
+    if (free_image_data && image_data) {
+        free(image_data);
+        image_data = NULL;
+    }
+
+    if (png_ptr && info_ptr) {
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+        png_ptr = NULL;
+        info_ptr = NULL;
+    }
+}
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/readpng.h b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/readpng.h
index ec6b483..fad9fe3 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/readpng.h
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/readpng.h
@@ -1,88 +1,88 @@
-/*---------------------------------------------------------------------------

-

-   rpng - simple PNG display program                              readpng.h

-

-  ---------------------------------------------------------------------------

-

-      Copyright (c) 1998-2007 Greg Roelofs.  All rights reserved.

-

-      This software is provided "as is," without warranty of any kind,

-      express or implied.  In no event shall the author or contributors

-      be held liable for any damages arising in any way from the use of

-      this software.

-

-      The contents of this file are DUAL-LICENSED.  You may modify and/or

-      redistribute this software according to the terms of one of the

-      following two licenses (at your option):

-

-

-      LICENSE 1 ("BSD-like with advertising clause"):

-

-      Permission is granted to anyone to use this software for any purpose,

-      including commercial applications, and to alter it and redistribute

-      it freely, subject to the following restrictions:

-

-      1. Redistributions of source code must retain the above copyright

-         notice, disclaimer, and this list of conditions.

-      2. Redistributions in binary form must reproduce the above copyright

-         notice, disclaimer, and this list of conditions in the documenta-

-         tion and/or other materials provided with the distribution.

-      3. All advertising materials mentioning features or use of this

-         software must display the following acknowledgment:

-

-            This product includes software developed by Greg Roelofs

-            and contributors for the book, "PNG: The Definitive Guide,"

-            published by O'Reilly and Associates.

-

-

-      LICENSE 2 (GNU GPL v2 or later):

-

-      This program is free software; you can redistribute it and/or modify

-      it under the terms of the GNU General Public License as published by

-      the Free Software Foundation; either version 2 of the License, or

-      (at your option) any later version.

-

-      This program is distributed in the hope that it will be useful,

-      but WITHOUT ANY WARRANTY; without even the implied warranty of

-      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

-      GNU General Public License for more details.

-

-      You should have received a copy of the GNU General Public License

-      along with this program; if not, write to the Free Software Foundation,

-      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

-

-  ---------------------------------------------------------------------------*/

-

-#ifndef TRUE

-#  define TRUE 1

-#  define FALSE 0

-#endif

-

-#ifndef MAX

-#  define MAX(a,b)  ((a) > (b)? (a) : (b))

-#  define MIN(a,b)  ((a) < (b)? (a) : (b))

-#endif

-

-#ifdef DEBUG

-#  define Trace(x)  {fprintf x ; fflush(stderr); fflush(stdout);}

-#else

-#  define Trace(x)  ;

-#endif

-

-typedef unsigned char   uch;

-typedef unsigned short  ush;

-typedef unsigned long   ulg;

-

-

-/* prototypes for public functions in readpng.c */

-

-void readpng_version_info(void);

-

-int readpng_init(FILE *infile, ulg *pWidth, ulg *pHeight);

-

-int readpng_get_bgcolor(uch *bg_red, uch *bg_green, uch *bg_blue);

-

-uch *readpng_get_image(double display_exponent, int *pChannels,

-                       ulg *pRowbytes);

-

-void readpng_cleanup(int free_image_data);

+/*---------------------------------------------------------------------------
+
+   rpng - simple PNG display program                              readpng.h
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-2007 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      The contents of this file are DUAL-LICENSED.  You may modify and/or
+      redistribute this software according to the terms of one of the
+      following two licenses (at your option):
+
+
+      LICENSE 1 ("BSD-like with advertising clause"):
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+
+      LICENSE 2 (GNU GPL v2 or later):
+
+      This program is free software; you can redistribute it and/or modify
+      it under the terms of the GNU General Public License as published by
+      the Free Software Foundation; either version 2 of the License, or
+      (at your option) any later version.
+
+      This program is distributed in the hope that it will be useful,
+      but WITHOUT ANY WARRANTY; without even the implied warranty of
+      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+      GNU General Public License for more details.
+
+      You should have received a copy of the GNU General Public License
+      along with this program; if not, write to the Free Software Foundation,
+      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+  ---------------------------------------------------------------------------*/
+
+#ifndef TRUE
+#  define TRUE 1
+#  define FALSE 0
+#endif
+
+#ifndef MAX
+#  define MAX(a,b)  ((a) > (b)? (a) : (b))
+#  define MIN(a,b)  ((a) < (b)? (a) : (b))
+#endif
+
+#ifdef DEBUG
+#  define Trace(x)  {fprintf x ; fflush(stderr); fflush(stdout);}
+#else
+#  define Trace(x)  ;
+#endif
+
+typedef unsigned char   uch;
+typedef unsigned short  ush;
+typedef unsigned long   ulg;
+
+
+/* prototypes for public functions in readpng.c */
+
+void readpng_version_info(void);
+
+int readpng_init(FILE *infile, ulg *pWidth, ulg *pHeight);
+
+int readpng_get_bgcolor(uch *bg_red, uch *bg_green, uch *bg_blue);
+
+uch *readpng_get_image(double display_exponent, int *pChannels,
+                       ulg *pRowbytes);
+
+void readpng_cleanup(int free_image_data);
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/readpng2.c b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/readpng2.c
index 3bbd2ec..b9746b7 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/readpng2.c
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/readpng2.c
@@ -1,511 +1,511 @@
-/*---------------------------------------------------------------------------

-

-   rpng2 - progressive-model PNG display program                 readpng2.c

-

-  ---------------------------------------------------------------------------

-

-      Copyright (c) 1998-2007 Greg Roelofs.  All rights reserved.

-

-      This software is provided "as is," without warranty of any kind,

-      express or implied.  In no event shall the author or contributors

-      be held liable for any damages arising in any way from the use of

-      this software.

-

-      The contents of this file are DUAL-LICENSED.  You may modify and/or

-      redistribute this software according to the terms of one of the

-      following two licenses (at your option):

-

-

-      LICENSE 1 ("BSD-like with advertising clause"):

-

-      Permission is granted to anyone to use this software for any purpose,

-      including commercial applications, and to alter it and redistribute

-      it freely, subject to the following restrictions:

-

-      1. Redistributions of source code must retain the above copyright

-         notice, disclaimer, and this list of conditions.

-      2. Redistributions in binary form must reproduce the above copyright

-         notice, disclaimer, and this list of conditions in the documenta-

-         tion and/or other materials provided with the distribution.

-      3. All advertising materials mentioning features or use of this

-         software must display the following acknowledgment:

-

-            This product includes software developed by Greg Roelofs

-            and contributors for the book, "PNG: The Definitive Guide,"

-            published by O'Reilly and Associates.

-

-

-      LICENSE 2 (GNU GPL v2 or later):

-

-      This program is free software; you can redistribute it and/or modify

-      it under the terms of the GNU General Public License as published by

-      the Free Software Foundation; either version 2 of the License, or

-      (at your option) any later version.

-

-      This program is distributed in the hope that it will be useful,

-      but WITHOUT ANY WARRANTY; without even the implied warranty of

-      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

-      GNU General Public License for more details.

-

-      You should have received a copy of the GNU General Public License

-      along with this program; if not, write to the Free Software Foundation,

-      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

-

-  ---------------------------------------------------------------------------*/

-

-

-#include <stdlib.h>     /* for exit() prototype */

-#include <setjmp.h>

-

-#include <zlib.h>

-#include "png.h"        /* libpng header from the local directory */

-#include "readpng2.h"   /* typedefs, common macros, public prototypes */

-

-

-/* local prototypes */

-

-static void readpng2_info_callback(png_structp png_ptr, png_infop info_ptr);

-static void readpng2_row_callback(png_structp png_ptr, png_bytep new_row,

-                                 png_uint_32 row_num, int pass);

-static void readpng2_end_callback(png_structp png_ptr, png_infop info_ptr);

-static void readpng2_error_handler(png_structp png_ptr, png_const_charp msg);

-

-

-

-

-void readpng2_version_info(void)

-{

-    fprintf(stderr, "   Compiled with libpng %s; using libpng %s\n",

-      PNG_LIBPNG_VER_STRING, png_libpng_ver);

-

-    fprintf(stderr, "   and with zlib %s; using zlib %s.\n",

-      ZLIB_VERSION, zlib_version);

-}

-

-

-

-

-int readpng2_check_sig(uch *sig, int num)

-{

-    return !png_sig_cmp(sig, 0, num);

-}

-

-

-

-

-/* returns 0 for success, 2 for libpng problem, 4 for out of memory */

-

-int readpng2_init(mainprog_info *mainprog_ptr)

-{

-    png_structp  png_ptr;       /* note:  temporary variables! */

-    png_infop  info_ptr;

-

-

-    /* could also replace libpng warning-handler (final NULL), but no need: */

-

-    png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, mainprog_ptr,

-      readpng2_error_handler, NULL);

-    if (!png_ptr)

-        return 4;   /* out of memory */

-

-    info_ptr = png_create_info_struct(png_ptr);

-    if (!info_ptr) {

-        png_destroy_read_struct(&png_ptr, NULL, NULL);

-        return 4;   /* out of memory */

-    }

-

-

-    /* we could create a second info struct here (end_info), but it's only

-     * useful if we want to keep pre- and post-IDAT chunk info separated

-     * (mainly for PNG-aware image editors and converters) */

-

-

-    /* setjmp() must be called in every function that calls a PNG-reading

-     * libpng function, unless an alternate error handler was installed--

-     * but compatible error handlers must either use longjmp() themselves

-     * (as in this program) or exit immediately, so here we are: */

-

-    if (setjmp(mainprog_ptr->jmpbuf)) {

-        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);

-        return 2;

-    }

-

-

-#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED

-    /* prepare the reader to ignore all recognized chunks whose data won't be

-     * used, i.e., all chunks recognized by libpng except for IHDR, PLTE, IDAT,

-     * IEND, tRNS, bKGD, gAMA, and sRGB (small performance improvement) */

-    {

-        /* These byte strings were copied from png.h.  If a future libpng

-         * version recognizes more chunks, add them to this list.  If a

-         * future version of readpng2.c recognizes more chunks, delete them

-         * from this list. */

-        static /* const */ png_byte chunks_to_ignore[] = {

-             99,  72,  82,  77, '\0',  /* cHRM */

-            104,  73,  83,  84, '\0',  /* hIST */

-            105,  67,  67,  80, '\0',  /* iCCP */

-            105,  84,  88, 116, '\0',  /* iTXt */

-            111,  70,  70, 115, '\0',  /* oFFs */

-            112,  67,  65,  76, '\0',  /* pCAL */

-            112,  72,  89, 115, '\0',  /* pHYs */

-            115,  66,  73,  84, '\0',  /* sBIT */

-            115,  67,  65,  76, '\0',  /* sCAL */

-            115,  80,  76,  84, '\0',  /* sPLT */

-            115,  84,  69,  82, '\0',  /* sTER */

-            116,  69,  88, 116, '\0',  /* tEXt */

-            116,  73,  77,  69, '\0',  /* tIME */

-            122,  84,  88, 116, '\0'   /* zTXt */

-        };

-

-        png_set_keep_unknown_chunks(png_ptr, 1 /* PNG_HANDLE_CHUNK_NEVER */,

-          chunks_to_ignore, sizeof(chunks_to_ignore)/5);

-    }

-#endif /* PNG_HANDLE_AS_UNKNOWN_SUPPORTED */

-

-

-    /* instead of doing png_init_io() here, now we set up our callback

-     * functions for progressive decoding */

-

-    png_set_progressive_read_fn(png_ptr, mainprog_ptr,

-      readpng2_info_callback, readpng2_row_callback, readpng2_end_callback);

-

-

-    /* make sure we save our pointers for use in readpng2_decode_data() */

-

-    mainprog_ptr->png_ptr = png_ptr;

-    mainprog_ptr->info_ptr = info_ptr;

-

-

-    /* and that's all there is to initialization */

-

-    return 0;

-}

-

-

-

-

-/* returns 0 for success, 2 for libpng (longjmp) problem */

-

-int readpng2_decode_data(mainprog_info *mainprog_ptr, uch *rawbuf, ulg length)

-{

-    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;

-    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;

-

-

-    /* setjmp() must be called in every function that calls a PNG-reading

-     * libpng function */

-

-    if (setjmp(mainprog_ptr->jmpbuf)) {

-        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);

-        mainprog_ptr->png_ptr = NULL;

-        mainprog_ptr->info_ptr = NULL;

-        return 2;

-    }

-

-

-    /* hand off the next chunk of input data to libpng for decoding */

-

-    png_process_data(png_ptr, info_ptr, rawbuf, length);

-

-    return 0;

-}

-

-

-

-

-static void readpng2_info_callback(png_structp png_ptr, png_infop info_ptr)

-{

-    mainprog_info  *mainprog_ptr;

-    int  color_type, bit_depth;

-    png_uint_32 width, height;

-#ifdef PNG_FLOATING_POINT_SUPPORTED

-    double  gamma;

-#else

-    png_fixed_point gamma;

-#endif

-

-

-    /* setjmp() doesn't make sense here, because we'd either have to exit(),

-     * longjmp() ourselves, or return control to libpng, which doesn't want

-     * to see us again.  By not doing anything here, libpng will instead jump

-     * to readpng2_decode_data(), which can return an error value to the main

-     * program. */

-

-

-    /* retrieve the pointer to our special-purpose struct, using the png_ptr

-     * that libpng passed back to us (i.e., not a global this time--there's

-     * no real difference for a single image, but for a multithreaded browser

-     * decoding several PNG images at the same time, one needs to avoid mixing

-     * up different images' structs) */

-

-    mainprog_ptr = png_get_progressive_ptr(png_ptr);

-

-    if (mainprog_ptr == NULL) {         /* we be hosed */

-        fprintf(stderr,

-          "readpng2 error:  main struct not recoverable in info_callback.\n");

-        fflush(stderr);

-        return;

-        /*

-         * Alternatively, we could call our error-handler just like libpng

-         * does, which would effectively terminate the program.  Since this

-         * can only happen if png_ptr gets redirected somewhere odd or the

-         * main PNG struct gets wiped, we're probably toast anyway.  (If

-         * png_ptr itself is NULL, we would not have been called.)

-         */

-    }

-

-

-    /* this is just like in the non-progressive case */

-

-    png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,

-       NULL, NULL, NULL);

-    mainprog_ptr->width = (ulg)width;

-    mainprog_ptr->height = (ulg)height;

-

-

-    /* since we know we've read all of the PNG file's "header" (i.e., up

-     * to IDAT), we can check for a background color here */

-

-    if (mainprog_ptr->need_bgcolor &&

-        png_get_valid(png_ptr, info_ptr, PNG_INFO_bKGD))

-    {

-        png_color_16p pBackground;

-

-        /* it is not obvious from the libpng documentation, but this function

-         * takes a pointer to a pointer, and it always returns valid red,

-         * green and blue values, regardless of color_type: */

-        png_get_bKGD(png_ptr, info_ptr, &pBackground);

-

-        /* however, it always returns the raw bKGD data, regardless of any

-         * bit-depth transformations, so check depth and adjust if necessary */

-        if (bit_depth == 16) {

-            mainprog_ptr->bg_red   = pBackground->red   >> 8;

-            mainprog_ptr->bg_green = pBackground->green >> 8;

-            mainprog_ptr->bg_blue  = pBackground->blue  >> 8;

-        } else if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8) {

-            if (bit_depth == 1)

-                mainprog_ptr->bg_red = mainprog_ptr->bg_green =

-                  mainprog_ptr->bg_blue = pBackground->gray? 255 : 0;

-            else if (bit_depth == 2)

-                mainprog_ptr->bg_red = mainprog_ptr->bg_green =

-                  mainprog_ptr->bg_blue = (255/3) * pBackground->gray;

-            else /* bit_depth == 4 */

-                mainprog_ptr->bg_red = mainprog_ptr->bg_green =

-                  mainprog_ptr->bg_blue = (255/15) * pBackground->gray;

-        } else {

-            mainprog_ptr->bg_red   = (uch)pBackground->red;

-            mainprog_ptr->bg_green = (uch)pBackground->green;

-            mainprog_ptr->bg_blue  = (uch)pBackground->blue;

-        }

-    }

-

-

-    /* as before, let libpng expand palette images to RGB, low-bit-depth

-     * grayscale images to 8 bits, transparency chunks to full alpha channel;

-     * strip 16-bit-per-sample images to 8 bits per sample; and convert

-     * grayscale to RGB[A] */

-

-    if (color_type == PNG_COLOR_TYPE_PALETTE)

-        png_set_expand(png_ptr);

-    if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)

-        png_set_expand(png_ptr);

-    if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))

-        png_set_expand(png_ptr);

-#ifdef PNG_READ_16_TO_8_SUPPORTED

-    if (bit_depth == 16)

-#  ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED

-        png_set_scale_16(png_ptr);

-#  else

-        png_set_strip_16(png_ptr);

-#  endif

-#endif

-    if (color_type == PNG_COLOR_TYPE_GRAY ||

-        color_type == PNG_COLOR_TYPE_GRAY_ALPHA)

-        png_set_gray_to_rgb(png_ptr);

-

-

-    /* Unlike the basic viewer, which was designed to operate on local files,

-     * this program is intended to simulate a web browser--even though we

-     * actually read from a local file, too.  But because we are pretending

-     * that most of the images originate on the Internet, we follow the recom-

-     * mendation of the sRGB proposal and treat unlabelled images (no gAMA

-     * chunk) as existing in the sRGB color space.  That is, we assume that

-     * such images have a file gamma of 0.45455, which corresponds to a PC-like

-     * display system.  This change in assumptions will have no effect on a

-     * PC-like system, but on a Mac, SGI, NeXT or other system with a non-

-     * identity lookup table, it will darken unlabelled images, which effec-

-     * tively favors images from PC-like systems over those originating on

-     * the local platform.  Note that mainprog_ptr->display_exponent is the

-     * "gamma" value for the entire display system, i.e., the product of

-     * LUT_exponent and CRT_exponent. */

-

-#ifdef PNG_FLOATING_POINT_SUPPORTED

-    if (png_get_gAMA(png_ptr, info_ptr, &gamma))

-        png_set_gamma(png_ptr, mainprog_ptr->display_exponent, gamma);

-    else

-        png_set_gamma(png_ptr, mainprog_ptr->display_exponent, 0.45455);

-#else

-    if (png_get_gAMA_fixed(png_ptr, info_ptr, &gamma))

-        png_set_gamma_fixed(png_ptr,

-            (png_fixed_point)(100000*mainprog_ptr->display_exponent+.5), gamma);

-    else

-        png_set_gamma_fixed(png_ptr,

-            (png_fixed_point)(100000*mainprog_ptr->display_exponent+.5), 45455);

-#endif

-

-    /* we'll let libpng expand interlaced images, too */

-

-    mainprog_ptr->passes = png_set_interlace_handling(png_ptr);

-

-

-    /* all transformations have been registered; now update info_ptr data and

-     * then get rowbytes and channels */

-

-    png_read_update_info(png_ptr, info_ptr);

-

-    mainprog_ptr->rowbytes = (int)png_get_rowbytes(png_ptr, info_ptr);

-    mainprog_ptr->channels = png_get_channels(png_ptr, info_ptr);

-

-

-    /* Call the main program to allocate memory for the image buffer and

-     * initialize windows and whatnot.  (The old-style function-pointer

-     * invocation is used for compatibility with a few supposedly ANSI

-     * compilers that nevertheless barf on "fn_ptr()"-style syntax.) */

-

-    (*mainprog_ptr->mainprog_init)();

-

-

-    /* and that takes care of initialization */

-

-    return;

-}

-

-

-

-

-

-static void readpng2_row_callback(png_structp png_ptr, png_bytep new_row,

-                                  png_uint_32 row_num, int pass)

-{

-    mainprog_info  *mainprog_ptr;

-

-

-    /* first check whether the row differs from the previous pass; if not,

-     * nothing to combine or display */

-

-    if (!new_row)

-        return;

-

-

-    /* retrieve the pointer to our special-purpose struct so we can access

-     * the old rows and image-display callback function */

-

-    mainprog_ptr = png_get_progressive_ptr(png_ptr);

-

-

-    /* save the pass number for optional use by the front end */

-

-    mainprog_ptr->pass = pass;

-

-

-    /* have libpng either combine the new row data with the existing row data

-     * from previous passes (if interlaced) or else just copy the new row

-     * into the main program's image buffer */

-

-    png_progressive_combine_row(png_ptr, mainprog_ptr->row_pointers[row_num],

-      new_row);

-

-

-    /* finally, call the display routine in the main program with the number

-     * of the row we just updated */

-

-    (*mainprog_ptr->mainprog_display_row)(row_num);

-

-

-    /* and we're ready for more */

-

-    return;

-}

-

-

-

-

-

-static void readpng2_end_callback(png_structp png_ptr, png_infop info_ptr)

-{

-    mainprog_info  *mainprog_ptr;

-

-

-    /* retrieve the pointer to our special-purpose struct */

-

-    mainprog_ptr = png_get_progressive_ptr(png_ptr);

-

-

-    /* let the main program know that it should flush any buffered image

-     * data to the display now and set a "done" flag or whatever, but note

-     * that it SHOULD NOT DESTROY THE PNG STRUCTS YET--in other words, do

-     * NOT call readpng2_cleanup() either here or in the finish_display()

-     * routine; wait until control returns to the main program via

-     * readpng2_decode_data() */

-

-    (*mainprog_ptr->mainprog_finish_display)();

-

-

-    /* all done */

-

-    return;

-}

-

-

-

-

-

-void readpng2_cleanup(mainprog_info *mainprog_ptr)

-{

-    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;

-    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;

-

-    if (png_ptr && info_ptr)

-        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);

-

-    mainprog_ptr->png_ptr = NULL;

-    mainprog_ptr->info_ptr = NULL;

-}

-

-

-

-

-

-static void readpng2_error_handler(png_structp png_ptr, png_const_charp msg)

-{

-    mainprog_info  *mainprog_ptr;

-

-    /* This function, aside from the extra step of retrieving the "error

-     * pointer" (below) and the fact that it exists within the application

-     * rather than within libpng, is essentially identical to libpng's

-     * default error handler.  The second point is critical:  since both

-     * setjmp() and longjmp() are called from the same code, they are

-     * guaranteed to have compatible notions of how big a jmp_buf is,

-     * regardless of whether _BSD_SOURCE or anything else has (or has not)

-     * been defined. */

-

-    fprintf(stderr, "readpng2 libpng error: %s\n", msg);

-    fflush(stderr);

-

-    mainprog_ptr = png_get_error_ptr(png_ptr);

-    if (mainprog_ptr == NULL) {         /* we are completely hosed now */

-        fprintf(stderr,

-          "readpng2 severe error:  jmpbuf not recoverable; terminating.\n");

-        fflush(stderr);

-        exit(99);

-    }

-

-    /* Now we have our data structure we can use the information in it

-     * to return control to our own higher level code (all the points

-     * where 'setjmp' is called in this file.)  This will work with other

-     * error handling mechanisms as well - libpng always calls png_error

-     * when it can proceed no further, thus, so long as the error handler

-     * is intercepted, application code can do its own error recovery.

-     */

-    longjmp(mainprog_ptr->jmpbuf, 1);

-}

+/*---------------------------------------------------------------------------
+
+   rpng2 - progressive-model PNG display program                 readpng2.c
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-2007 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      The contents of this file are DUAL-LICENSED.  You may modify and/or
+      redistribute this software according to the terms of one of the
+      following two licenses (at your option):
+
+
+      LICENSE 1 ("BSD-like with advertising clause"):
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+
+      LICENSE 2 (GNU GPL v2 or later):
+
+      This program is free software; you can redistribute it and/or modify
+      it under the terms of the GNU General Public License as published by
+      the Free Software Foundation; either version 2 of the License, or
+      (at your option) any later version.
+
+      This program is distributed in the hope that it will be useful,
+      but WITHOUT ANY WARRANTY; without even the implied warranty of
+      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+      GNU General Public License for more details.
+
+      You should have received a copy of the GNU General Public License
+      along with this program; if not, write to the Free Software Foundation,
+      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+  ---------------------------------------------------------------------------*/
+
+
+#include <stdlib.h>     /* for exit() prototype */
+#include <setjmp.h>
+
+#include <zlib.h>
+#include "png.h"        /* libpng header from the local directory */
+#include "readpng2.h"   /* typedefs, common macros, public prototypes */
+
+
+/* local prototypes */
+
+static void readpng2_info_callback(png_structp png_ptr, png_infop info_ptr);
+static void readpng2_row_callback(png_structp png_ptr, png_bytep new_row,
+                                 png_uint_32 row_num, int pass);
+static void readpng2_end_callback(png_structp png_ptr, png_infop info_ptr);
+static void readpng2_error_handler(png_structp png_ptr, png_const_charp msg);
+
+
+
+
+void readpng2_version_info(void)
+{
+    fprintf(stderr, "   Compiled with libpng %s; using libpng %s\n",
+      PNG_LIBPNG_VER_STRING, png_libpng_ver);
+
+    fprintf(stderr, "   and with zlib %s; using zlib %s.\n",
+      ZLIB_VERSION, zlib_version);
+}
+
+
+
+
+int readpng2_check_sig(uch *sig, int num)
+{
+    return !png_sig_cmp(sig, 0, num);
+}
+
+
+
+
+/* returns 0 for success, 2 for libpng problem, 4 for out of memory */
+
+int readpng2_init(mainprog_info *mainprog_ptr)
+{
+    png_structp  png_ptr;       /* note:  temporary variables! */
+    png_infop  info_ptr;
+
+
+    /* could also replace libpng warning-handler (final NULL), but no need: */
+
+    png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, mainprog_ptr,
+      readpng2_error_handler, NULL);
+    if (!png_ptr)
+        return 4;   /* out of memory */
+
+    info_ptr = png_create_info_struct(png_ptr);
+    if (!info_ptr) {
+        png_destroy_read_struct(&png_ptr, NULL, NULL);
+        return 4;   /* out of memory */
+    }
+
+
+    /* we could create a second info struct here (end_info), but it's only
+     * useful if we want to keep pre- and post-IDAT chunk info separated
+     * (mainly for PNG-aware image editors and converters) */
+
+
+    /* setjmp() must be called in every function that calls a PNG-reading
+     * libpng function, unless an alternate error handler was installed--
+     * but compatible error handlers must either use longjmp() themselves
+     * (as in this program) or exit immediately, so here we are: */
+
+    if (setjmp(mainprog_ptr->jmpbuf)) {
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+        return 2;
+    }
+
+
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+    /* prepare the reader to ignore all recognized chunks whose data won't be
+     * used, i.e., all chunks recognized by libpng except for IHDR, PLTE, IDAT,
+     * IEND, tRNS, bKGD, gAMA, and sRGB (small performance improvement) */
+    {
+        /* These byte strings were copied from png.h.  If a future libpng
+         * version recognizes more chunks, add them to this list.  If a
+         * future version of readpng2.c recognizes more chunks, delete them
+         * from this list. */
+        static /* const */ png_byte chunks_to_ignore[] = {
+             99,  72,  82,  77, '\0',  /* cHRM */
+            104,  73,  83,  84, '\0',  /* hIST */
+            105,  67,  67,  80, '\0',  /* iCCP */
+            105,  84,  88, 116, '\0',  /* iTXt */
+            111,  70,  70, 115, '\0',  /* oFFs */
+            112,  67,  65,  76, '\0',  /* pCAL */
+            112,  72,  89, 115, '\0',  /* pHYs */
+            115,  66,  73,  84, '\0',  /* sBIT */
+            115,  67,  65,  76, '\0',  /* sCAL */
+            115,  80,  76,  84, '\0',  /* sPLT */
+            115,  84,  69,  82, '\0',  /* sTER */
+            116,  69,  88, 116, '\0',  /* tEXt */
+            116,  73,  77,  69, '\0',  /* tIME */
+            122,  84,  88, 116, '\0'   /* zTXt */
+        };
+
+        png_set_keep_unknown_chunks(png_ptr, 1 /* PNG_HANDLE_CHUNK_NEVER */,
+          chunks_to_ignore, sizeof(chunks_to_ignore)/5);
+    }
+#endif /* PNG_HANDLE_AS_UNKNOWN_SUPPORTED */
+
+
+    /* instead of doing png_init_io() here, now we set up our callback
+     * functions for progressive decoding */
+
+    png_set_progressive_read_fn(png_ptr, mainprog_ptr,
+      readpng2_info_callback, readpng2_row_callback, readpng2_end_callback);
+
+
+    /* make sure we save our pointers for use in readpng2_decode_data() */
+
+    mainprog_ptr->png_ptr = png_ptr;
+    mainprog_ptr->info_ptr = info_ptr;
+
+
+    /* and that's all there is to initialization */
+
+    return 0;
+}
+
+
+
+
+/* returns 0 for success, 2 for libpng (longjmp) problem */
+
+int readpng2_decode_data(mainprog_info *mainprog_ptr, uch *rawbuf, ulg length)
+{
+    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;
+    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;
+
+
+    /* setjmp() must be called in every function that calls a PNG-reading
+     * libpng function */
+
+    if (setjmp(mainprog_ptr->jmpbuf)) {
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+        mainprog_ptr->png_ptr = NULL;
+        mainprog_ptr->info_ptr = NULL;
+        return 2;
+    }
+
+
+    /* hand off the next chunk of input data to libpng for decoding */
+
+    png_process_data(png_ptr, info_ptr, rawbuf, length);
+
+    return 0;
+}
+
+
+
+
+static void readpng2_info_callback(png_structp png_ptr, png_infop info_ptr)
+{
+    mainprog_info  *mainprog_ptr;
+    int  color_type, bit_depth;
+    png_uint_32 width, height;
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+    double  gamma;
+#else
+    png_fixed_point gamma;
+#endif
+
+
+    /* setjmp() doesn't make sense here, because we'd either have to exit(),
+     * longjmp() ourselves, or return control to libpng, which doesn't want
+     * to see us again.  By not doing anything here, libpng will instead jump
+     * to readpng2_decode_data(), which can return an error value to the main
+     * program. */
+
+
+    /* retrieve the pointer to our special-purpose struct, using the png_ptr
+     * that libpng passed back to us (i.e., not a global this time--there's
+     * no real difference for a single image, but for a multithreaded browser
+     * decoding several PNG images at the same time, one needs to avoid mixing
+     * up different images' structs) */
+
+    mainprog_ptr = png_get_progressive_ptr(png_ptr);
+
+    if (mainprog_ptr == NULL) {         /* we be hosed */
+        fprintf(stderr,
+          "readpng2 error:  main struct not recoverable in info_callback.\n");
+        fflush(stderr);
+        return;
+        /*
+         * Alternatively, we could call our error-handler just like libpng
+         * does, which would effectively terminate the program.  Since this
+         * can only happen if png_ptr gets redirected somewhere odd or the
+         * main PNG struct gets wiped, we're probably toast anyway.  (If
+         * png_ptr itself is NULL, we would not have been called.)
+         */
+    }
+
+
+    /* this is just like in the non-progressive case */
+
+    png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
+       NULL, NULL, NULL);
+    mainprog_ptr->width = (ulg)width;
+    mainprog_ptr->height = (ulg)height;
+
+
+    /* since we know we've read all of the PNG file's "header" (i.e., up
+     * to IDAT), we can check for a background color here */
+
+    if (mainprog_ptr->need_bgcolor &&
+        png_get_valid(png_ptr, info_ptr, PNG_INFO_bKGD))
+    {
+        png_color_16p pBackground;
+
+        /* it is not obvious from the libpng documentation, but this function
+         * takes a pointer to a pointer, and it always returns valid red,
+         * green and blue values, regardless of color_type: */
+        png_get_bKGD(png_ptr, info_ptr, &pBackground);
+
+        /* however, it always returns the raw bKGD data, regardless of any
+         * bit-depth transformations, so check depth and adjust if necessary */
+        if (bit_depth == 16) {
+            mainprog_ptr->bg_red   = pBackground->red   >> 8;
+            mainprog_ptr->bg_green = pBackground->green >> 8;
+            mainprog_ptr->bg_blue  = pBackground->blue  >> 8;
+        } else if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8) {
+            if (bit_depth == 1)
+                mainprog_ptr->bg_red = mainprog_ptr->bg_green =
+                  mainprog_ptr->bg_blue = pBackground->gray? 255 : 0;
+            else if (bit_depth == 2)
+                mainprog_ptr->bg_red = mainprog_ptr->bg_green =
+                  mainprog_ptr->bg_blue = (255/3) * pBackground->gray;
+            else /* bit_depth == 4 */
+                mainprog_ptr->bg_red = mainprog_ptr->bg_green =
+                  mainprog_ptr->bg_blue = (255/15) * pBackground->gray;
+        } else {
+            mainprog_ptr->bg_red   = (uch)pBackground->red;
+            mainprog_ptr->bg_green = (uch)pBackground->green;
+            mainprog_ptr->bg_blue  = (uch)pBackground->blue;
+        }
+    }
+
+
+    /* as before, let libpng expand palette images to RGB, low-bit-depth
+     * grayscale images to 8 bits, transparency chunks to full alpha channel;
+     * strip 16-bit-per-sample images to 8 bits per sample; and convert
+     * grayscale to RGB[A] */
+
+    if (color_type == PNG_COLOR_TYPE_PALETTE)
+        png_set_expand(png_ptr);
+    if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
+        png_set_expand(png_ptr);
+    if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))
+        png_set_expand(png_ptr);
+#ifdef PNG_READ_16_TO_8_SUPPORTED
+    if (bit_depth == 16)
+#  ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
+        png_set_scale_16(png_ptr);
+#  else
+        png_set_strip_16(png_ptr);
+#  endif
+#endif
+    if (color_type == PNG_COLOR_TYPE_GRAY ||
+        color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+        png_set_gray_to_rgb(png_ptr);
+
+
+    /* Unlike the basic viewer, which was designed to operate on local files,
+     * this program is intended to simulate a web browser--even though we
+     * actually read from a local file, too.  But because we are pretending
+     * that most of the images originate on the Internet, we follow the recom-
+     * mendation of the sRGB proposal and treat unlabelled images (no gAMA
+     * chunk) as existing in the sRGB color space.  That is, we assume that
+     * such images have a file gamma of 0.45455, which corresponds to a PC-like
+     * display system.  This change in assumptions will have no effect on a
+     * PC-like system, but on a Mac, SGI, NeXT or other system with a non-
+     * identity lookup table, it will darken unlabelled images, which effec-
+     * tively favors images from PC-like systems over those originating on
+     * the local platform.  Note that mainprog_ptr->display_exponent is the
+     * "gamma" value for the entire display system, i.e., the product of
+     * LUT_exponent and CRT_exponent. */
+
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+    if (png_get_gAMA(png_ptr, info_ptr, &gamma))
+        png_set_gamma(png_ptr, mainprog_ptr->display_exponent, gamma);
+    else
+        png_set_gamma(png_ptr, mainprog_ptr->display_exponent, 0.45455);
+#else
+    if (png_get_gAMA_fixed(png_ptr, info_ptr, &gamma))
+        png_set_gamma_fixed(png_ptr,
+            (png_fixed_point)(100000*mainprog_ptr->display_exponent+.5), gamma);
+    else
+        png_set_gamma_fixed(png_ptr,
+            (png_fixed_point)(100000*mainprog_ptr->display_exponent+.5), 45455);
+#endif
+
+    /* we'll let libpng expand interlaced images, too */
+
+    mainprog_ptr->passes = png_set_interlace_handling(png_ptr);
+
+
+    /* all transformations have been registered; now update info_ptr data and
+     * then get rowbytes and channels */
+
+    png_read_update_info(png_ptr, info_ptr);
+
+    mainprog_ptr->rowbytes = (int)png_get_rowbytes(png_ptr, info_ptr);
+    mainprog_ptr->channels = png_get_channels(png_ptr, info_ptr);
+
+
+    /* Call the main program to allocate memory for the image buffer and
+     * initialize windows and whatnot.  (The old-style function-pointer
+     * invocation is used for compatibility with a few supposedly ANSI
+     * compilers that nevertheless barf on "fn_ptr()"-style syntax.) */
+
+    (*mainprog_ptr->mainprog_init)();
+
+
+    /* and that takes care of initialization */
+
+    return;
+}
+
+
+
+
+
+static void readpng2_row_callback(png_structp png_ptr, png_bytep new_row,
+                                  png_uint_32 row_num, int pass)
+{
+    mainprog_info  *mainprog_ptr;
+
+
+    /* first check whether the row differs from the previous pass; if not,
+     * nothing to combine or display */
+
+    if (!new_row)
+        return;
+
+
+    /* retrieve the pointer to our special-purpose struct so we can access
+     * the old rows and image-display callback function */
+
+    mainprog_ptr = png_get_progressive_ptr(png_ptr);
+
+
+    /* save the pass number for optional use by the front end */
+
+    mainprog_ptr->pass = pass;
+
+
+    /* have libpng either combine the new row data with the existing row data
+     * from previous passes (if interlaced) or else just copy the new row
+     * into the main program's image buffer */
+
+    png_progressive_combine_row(png_ptr, mainprog_ptr->row_pointers[row_num],
+      new_row);
+
+
+    /* finally, call the display routine in the main program with the number
+     * of the row we just updated */
+
+    (*mainprog_ptr->mainprog_display_row)(row_num);
+
+
+    /* and we're ready for more */
+
+    return;
+}
+
+
+
+
+
+static void readpng2_end_callback(png_structp png_ptr, png_infop info_ptr)
+{
+    mainprog_info  *mainprog_ptr;
+
+
+    /* retrieve the pointer to our special-purpose struct */
+
+    mainprog_ptr = png_get_progressive_ptr(png_ptr);
+
+
+    /* let the main program know that it should flush any buffered image
+     * data to the display now and set a "done" flag or whatever, but note
+     * that it SHOULD NOT DESTROY THE PNG STRUCTS YET--in other words, do
+     * NOT call readpng2_cleanup() either here or in the finish_display()
+     * routine; wait until control returns to the main program via
+     * readpng2_decode_data() */
+
+    (*mainprog_ptr->mainprog_finish_display)();
+
+
+    /* all done */
+
+    return;
+}
+
+
+
+
+
+void readpng2_cleanup(mainprog_info *mainprog_ptr)
+{
+    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;
+    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;
+
+    if (png_ptr && info_ptr)
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+
+    mainprog_ptr->png_ptr = NULL;
+    mainprog_ptr->info_ptr = NULL;
+}
+
+
+
+
+
+static void readpng2_error_handler(png_structp png_ptr, png_const_charp msg)
+{
+    mainprog_info  *mainprog_ptr;
+
+    /* This function, aside from the extra step of retrieving the "error
+     * pointer" (below) and the fact that it exists within the application
+     * rather than within libpng, is essentially identical to libpng's
+     * default error handler.  The second point is critical:  since both
+     * setjmp() and longjmp() are called from the same code, they are
+     * guaranteed to have compatible notions of how big a jmp_buf is,
+     * regardless of whether _BSD_SOURCE or anything else has (or has not)
+     * been defined. */
+
+    fprintf(stderr, "readpng2 libpng error: %s\n", msg);
+    fflush(stderr);
+
+    mainprog_ptr = png_get_error_ptr(png_ptr);
+    if (mainprog_ptr == NULL) {         /* we are completely hosed now */
+        fprintf(stderr,
+          "readpng2 severe error:  jmpbuf not recoverable; terminating.\n");
+        fflush(stderr);
+        exit(99);
+    }
+
+    /* Now we have our data structure we can use the information in it
+     * to return control to our own higher level code (all the points
+     * where 'setjmp' is called in this file.)  This will work with other
+     * error handling mechanisms as well - libpng always calls png_error
+     * when it can proceed no further, thus, so long as the error handler
+     * is intercepted, application code can do its own error recovery.
+     */
+    longjmp(mainprog_ptr->jmpbuf, 1);
+}
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/readpng2.h b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/readpng2.h
index 7a59263..6b3660d 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/readpng2.h
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/readpng2.h
@@ -1,116 +1,116 @@
-/*---------------------------------------------------------------------------

-

-   rpng2 - progressive-model PNG display program                 readpng2.h

-

-  ---------------------------------------------------------------------------

-

-      Copyright (c) 1998-2008 Greg Roelofs.  All rights reserved.

-

-      This software is provided "as is," without warranty of any kind,

-      express or implied.  In no event shall the author or contributors

-      be held liable for any damages arising in any way from the use of

-      this software.

-

-      The contents of this file are DUAL-LICENSED.  You may modify and/or

-      redistribute this software according to the terms of one of the

-      following two licenses (at your option):

-

-

-      LICENSE 1 ("BSD-like with advertising clause"):

-

-      Permission is granted to anyone to use this software for any purpose,

-      including commercial applications, and to alter it and redistribute

-      it freely, subject to the following restrictions:

-

-      1. Redistributions of source code must retain the above copyright

-         notice, disclaimer, and this list of conditions.

-      2. Redistributions in binary form must reproduce the above copyright

-         notice, disclaimer, and this list of conditions in the documenta-

-         tion and/or other materials provided with the distribution.

-      3. All advertising materials mentioning features or use of this

-         software must display the following acknowledgment:

-

-            This product includes software developed by Greg Roelofs

-            and contributors for the book, "PNG: The Definitive Guide,"

-            published by O'Reilly and Associates.

-

-

-      LICENSE 2 (GNU GPL v2 or later):

-

-      This program is free software; you can redistribute it and/or modify

-      it under the terms of the GNU General Public License as published by

-      the Free Software Foundation; either version 2 of the License, or

-      (at your option) any later version.

-

-      This program is distributed in the hope that it will be useful,

-      but WITHOUT ANY WARRANTY; without even the implied warranty of

-      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

-      GNU General Public License for more details.

-

-      You should have received a copy of the GNU General Public License

-      along with this program; if not, write to the Free Software Foundation,

-      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

-

-  ---------------------------------------------------------------------------*/

-

-#ifndef TRUE

-#  define TRUE 1

-#  define FALSE 0

-#endif

-

-#ifndef MAX

-#  define MAX(a,b)  ((a) > (b)? (a) : (b))

-#  define MIN(a,b)  ((a) < (b)? (a) : (b))

-#endif

-

-#ifdef DEBUG

-#  define Trace(x)  {fprintf x ; fflush(stderr); fflush(stdout);}

-#else

-#  define Trace(x)  ;

-#endif

-

-enum rpng2_states {

-    kPreInit = 0,

-    kWindowInit,

-    kDone

-};

-

-typedef unsigned char   uch;

-typedef unsigned short  ush;

-typedef unsigned long   ulg;

-

-typedef struct _mainprog_info {

-    double display_exponent;

-    ulg width;

-    ulg height;

-    void *png_ptr;

-    void *info_ptr;

-    void (*mainprog_init)(void);

-    void (*mainprog_display_row)(ulg row_num);

-    void (*mainprog_finish_display)(void);

-    uch *image_data;

-    uch **row_pointers;

-    jmp_buf jmpbuf;

-    int passes;              /* not used */

-    int pass;

-    int rowbytes;

-    int channels;

-    int need_bgcolor;

-    int state;

-    uch bg_red;

-    uch bg_green;

-    uch bg_blue;

-} mainprog_info;

-

-

-/* prototypes for public functions in readpng2.c */

-

-void readpng2_version_info(void);

-

-int readpng2_check_sig(uch *sig, int num);

-

-int readpng2_init(mainprog_info *mainprog_ptr);

-

-int readpng2_decode_data(mainprog_info *mainprog_ptr, uch *rawbuf, ulg length);

-

-void readpng2_cleanup(mainprog_info *mainprog_ptr);

+/*---------------------------------------------------------------------------
+
+   rpng2 - progressive-model PNG display program                 readpng2.h
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-2008 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      The contents of this file are DUAL-LICENSED.  You may modify and/or
+      redistribute this software according to the terms of one of the
+      following two licenses (at your option):
+
+
+      LICENSE 1 ("BSD-like with advertising clause"):
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+
+      LICENSE 2 (GNU GPL v2 or later):
+
+      This program is free software; you can redistribute it and/or modify
+      it under the terms of the GNU General Public License as published by
+      the Free Software Foundation; either version 2 of the License, or
+      (at your option) any later version.
+
+      This program is distributed in the hope that it will be useful,
+      but WITHOUT ANY WARRANTY; without even the implied warranty of
+      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+      GNU General Public License for more details.
+
+      You should have received a copy of the GNU General Public License
+      along with this program; if not, write to the Free Software Foundation,
+      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+  ---------------------------------------------------------------------------*/
+
+#ifndef TRUE
+#  define TRUE 1
+#  define FALSE 0
+#endif
+
+#ifndef MAX
+#  define MAX(a,b)  ((a) > (b)? (a) : (b))
+#  define MIN(a,b)  ((a) < (b)? (a) : (b))
+#endif
+
+#ifdef DEBUG
+#  define Trace(x)  {fprintf x ; fflush(stderr); fflush(stdout);}
+#else
+#  define Trace(x)  ;
+#endif
+
+enum rpng2_states {
+    kPreInit = 0,
+    kWindowInit,
+    kDone
+};
+
+typedef unsigned char   uch;
+typedef unsigned short  ush;
+typedef unsigned long   ulg;
+
+typedef struct _mainprog_info {
+    double display_exponent;
+    ulg width;
+    ulg height;
+    void *png_ptr;
+    void *info_ptr;
+    void (*mainprog_init)(void);
+    void (*mainprog_display_row)(ulg row_num);
+    void (*mainprog_finish_display)(void);
+    uch *image_data;
+    uch **row_pointers;
+    jmp_buf jmpbuf;
+    int passes;              /* not used */
+    int pass;
+    int rowbytes;
+    int channels;
+    int need_bgcolor;
+    int state;
+    uch bg_red;
+    uch bg_green;
+    uch bg_blue;
+} mainprog_info;
+
+
+/* prototypes for public functions in readpng2.c */
+
+void readpng2_version_info(void);
+
+int readpng2_check_sig(uch *sig, int num);
+
+int readpng2_init(mainprog_info *mainprog_ptr);
+
+int readpng2_decode_data(mainprog_info *mainprog_ptr, uch *rawbuf, ulg length);
+
+void readpng2_cleanup(mainprog_info *mainprog_ptr);
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/readppm.c b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/readppm.c
index 1ba2092..be9a56d 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/readppm.c
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/readppm.c
@@ -1,179 +1,179 @@
-/*---------------------------------------------------------------------------

-

-   rpng - simple PNG display program                              readppm.c

-

-  ---------------------------------------------------------------------------

-

-   This is a special-purpose replacement for readpng.c that allows binary

-   PPM files to be used in place of PNG images.

-

-  ---------------------------------------------------------------------------

-

-      Copyright (c) 1998-2007 Greg Roelofs.  All rights reserved.

-

-      This software is provided "as is," without warranty of any kind,

-      express or implied.  In no event shall the author or contributors

-      be held liable for any damages arising in any way from the use of

-      this software.

-

-      The contents of this file are DUAL-LICENSED.  You may modify and/or

-      redistribute this software according to the terms of one of the

-      following two licenses (at your option):

-

-

-      LICENSE 1 ("BSD-like with advertising clause"):

-

-      Permission is granted to anyone to use this software for any purpose,

-      including commercial applications, and to alter it and redistribute

-      it freely, subject to the following restrictions:

-

-      1. Redistributions of source code must retain the above copyright

-         notice, disclaimer, and this list of conditions.

-      2. Redistributions in binary form must reproduce the above copyright

-         notice, disclaimer, and this list of conditions in the documenta-

-         tion and/or other materials provided with the distribution.

-      3. All advertising materials mentioning features or use of this

-         software must display the following acknowledgment:

-

-            This product includes software developed by Greg Roelofs

-            and contributors for the book, "PNG: The Definitive Guide,"

-            published by O'Reilly and Associates.

-

-

-      LICENSE 2 (GNU GPL v2 or later):

-

-      This program is free software; you can redistribute it and/or modify

-      it under the terms of the GNU General Public License as published by

-      the Free Software Foundation; either version 2 of the License, or

-      (at your option) any later version.

-

-      This program is distributed in the hope that it will be useful,

-      but WITHOUT ANY WARRANTY; without even the implied warranty of

-      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

-      GNU General Public License for more details.

-

-      You should have received a copy of the GNU General Public License

-      along with this program; if not, write to the Free Software Foundation,

-      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

-

-  ---------------------------------------------------------------------------*/

-

-#include <stdio.h>

-#include <stdlib.h>

-

-#include "readpng.h"    /* typedefs, common macros, public prototypes */

-

-

-ulg  width, height;

-int  bit_depth, color_type, channels;

-uch  *image_data = NULL;

-FILE *saved_infile;

-

-

-void readpng_version_info()

-{

-    fprintf(stderr, "   Compiled without libpng, zlib or PBMPLUS/NetPBM.\n");

-}

-

-

-/* return value = 0 for success, 1 for bad sig, 2 for bad IHDR, 4 for no mem */

-

-int readpng_init(FILE *infile, ulg *pWidth, ulg *pHeight)

-{

-    static uch ppmline[256];

-    int maxval;

-

-

-    saved_infile = infile;

-

-    fgets(ppmline, 256, infile);

-    if (ppmline[0] != 'P' || ppmline[1] != '6') {

-        fprintf(stderr, "ERROR:  not a PPM file\n");

-        return 1;

-    }

-    /* possible color types:  P5 = grayscale (0), P6 = RGB (2), P8 = RGBA (6) */

-    if (ppmline[1] == '6') {

-        color_type = 2;

-        channels = 3;

-    } else if (ppmline[1] == '8') {

-        color_type = 6;

-        channels = 4;

-    } else /* if (ppmline[1] == '5') */ {

-        color_type = 0;

-        channels = 1;

-    }

-

-    do {

-        fgets(ppmline, 256, infile);

-    } while (ppmline[0] == '#');

-    sscanf(ppmline, "%lu %lu", &width, &height);

-

-    do {

-        fgets(ppmline, 256, infile);

-    } while (ppmline[0] == '#');

-    sscanf(ppmline, "%d", &maxval);

-    if (maxval != 255) {

-        fprintf(stderr, "ERROR:  maxval = %d\n", maxval);

-        return 2;

-    }

-    bit_depth = 8;

-

-    *pWidth = width;

-    *pHeight = height;

-

-    return 0;

-}

-

-

-

-

-/* returns 0 if succeeds, 1 if fails due to no bKGD chunk, 2 if libpng error;

- * scales values to 8-bit if necessary */

-

-int readpng_get_bgcolor(uch *red, uch *green, uch *blue)

-{

-    return 1;

-}

-

-

-

-

-/* display_exponent == LUT_exponent * CRT_exponent */

-

-uch *readpng_get_image(double display_exponent, int *pChannels, ulg *pRowbytes)

-{

-    ulg  rowbytes;

-

-

-    /* expand palette images to RGB, low-bit-depth grayscale images to 8 bits,

-     * transparency chunks to full alpha channel; strip 16-bit-per-sample

-     * images to 8 bits per sample; and convert grayscale to RGB[A] */

-

-    /* GRR WARNING:  grayscale needs to be expanded and channels reset! */

-

-    *pRowbytes = rowbytes = channels*width;

-    *pChannels = channels;

-

-    if ((image_data = (uch *)malloc(rowbytes*height)) == NULL) {

-        return NULL;

-    }

-

-    Trace((stderr, "readpng_get_image:  rowbytes = %ld, height = %ld\n", rowbytes, height));

-

-

-    /* now we can go ahead and just read the whole image */

-

-    fread(image_data, 1L, rowbytes*height, saved_infile);

-

-

-    return image_data;

-}

-

-

-void readpng_cleanup(int free_image_data)

-{

-    if (free_image_data && image_data) {

-        free(image_data);

-        image_data = NULL;

-    }

-}

+/*---------------------------------------------------------------------------
+
+   rpng - simple PNG display program                              readppm.c
+
+  ---------------------------------------------------------------------------
+
+   This is a special-purpose replacement for readpng.c that allows binary
+   PPM files to be used in place of PNG images.
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-2007 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      The contents of this file are DUAL-LICENSED.  You may modify and/or
+      redistribute this software according to the terms of one of the
+      following two licenses (at your option):
+
+
+      LICENSE 1 ("BSD-like with advertising clause"):
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+
+      LICENSE 2 (GNU GPL v2 or later):
+
+      This program is free software; you can redistribute it and/or modify
+      it under the terms of the GNU General Public License as published by
+      the Free Software Foundation; either version 2 of the License, or
+      (at your option) any later version.
+
+      This program is distributed in the hope that it will be useful,
+      but WITHOUT ANY WARRANTY; without even the implied warranty of
+      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+      GNU General Public License for more details.
+
+      You should have received a copy of the GNU General Public License
+      along with this program; if not, write to the Free Software Foundation,
+      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+  ---------------------------------------------------------------------------*/
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "readpng.h"    /* typedefs, common macros, public prototypes */
+
+
+ulg  width, height;
+int  bit_depth, color_type, channels;
+uch  *image_data = NULL;
+FILE *saved_infile;
+
+
+void readpng_version_info()
+{
+    fprintf(stderr, "   Compiled without libpng, zlib or PBMPLUS/NetPBM.\n");
+}
+
+
+/* return value = 0 for success, 1 for bad sig, 2 for bad IHDR, 4 for no mem */
+
+int readpng_init(FILE *infile, ulg *pWidth, ulg *pHeight)
+{
+    static uch ppmline[256];
+    int maxval;
+
+
+    saved_infile = infile;
+
+    fgets(ppmline, 256, infile);
+    if (ppmline[0] != 'P' || ppmline[1] != '6') {
+        fprintf(stderr, "ERROR:  not a PPM file\n");
+        return 1;
+    }
+    /* possible color types:  P5 = grayscale (0), P6 = RGB (2), P8 = RGBA (6) */
+    if (ppmline[1] == '6') {
+        color_type = 2;
+        channels = 3;
+    } else if (ppmline[1] == '8') {
+        color_type = 6;
+        channels = 4;
+    } else /* if (ppmline[1] == '5') */ {
+        color_type = 0;
+        channels = 1;
+    }
+
+    do {
+        fgets(ppmline, 256, infile);
+    } while (ppmline[0] == '#');
+    sscanf(ppmline, "%lu %lu", &width, &height);
+
+    do {
+        fgets(ppmline, 256, infile);
+    } while (ppmline[0] == '#');
+    sscanf(ppmline, "%d", &maxval);
+    if (maxval != 255) {
+        fprintf(stderr, "ERROR:  maxval = %d\n", maxval);
+        return 2;
+    }
+    bit_depth = 8;
+
+    *pWidth = width;
+    *pHeight = height;
+
+    return 0;
+}
+
+
+
+
+/* returns 0 if succeeds, 1 if fails due to no bKGD chunk, 2 if libpng error;
+ * scales values to 8-bit if necessary */
+
+int readpng_get_bgcolor(uch *red, uch *green, uch *blue)
+{
+    return 1;
+}
+
+
+
+
+/* display_exponent == LUT_exponent * CRT_exponent */
+
+uch *readpng_get_image(double display_exponent, int *pChannels, ulg *pRowbytes)
+{
+    ulg  rowbytes;
+
+
+    /* expand palette images to RGB, low-bit-depth grayscale images to 8 bits,
+     * transparency chunks to full alpha channel; strip 16-bit-per-sample
+     * images to 8 bits per sample; and convert grayscale to RGB[A] */
+
+    /* GRR WARNING:  grayscale needs to be expanded and channels reset! */
+
+    *pRowbytes = rowbytes = channels*width;
+    *pChannels = channels;
+
+    if ((image_data = (uch *)malloc(rowbytes*height)) == NULL) {
+        return NULL;
+    }
+
+    Trace((stderr, "readpng_get_image:  rowbytes = %ld, height = %ld\n", rowbytes, height));
+
+
+    /* now we can go ahead and just read the whole image */
+
+    fread(image_data, 1L, rowbytes*height, saved_infile);
+
+
+    return image_data;
+}
+
+
+void readpng_cleanup(int free_image_data)
+{
+    if (free_image_data && image_data) {
+        free(image_data);
+        image_data = NULL;
+    }
+}
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/rpng-win.c b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/rpng-win.c
index 1c22282..f53ddc8 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/rpng-win.c
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/rpng-win.c
@@ -1,728 +1,728 @@
-/*---------------------------------------------------------------------------

-

-   rpng - simple PNG display program                             rpng-win.c

-

-   This program decodes and displays PNG images, with gamma correction and

-   optionally with a user-specified background color (in case the image has

-   transparency).  It is very nearly the most basic PNG viewer possible.

-   This version is for 32-bit Windows; it may compile under 16-bit Windows

-   with a little tweaking (or maybe not).

-

-   to do:

-    - handle quoted command-line args (especially filenames with spaces)

-    - have minimum window width:  oh well

-    - use %.1023s to simplify truncation of title-bar string?

-

-  ---------------------------------------------------------------------------

-

-   Changelog:

-    - 1.00:  initial public release

-    - 1.01:  modified to allow abbreviated options; fixed long/ulong mis-

-              match; switched to png_jmpbuf() macro

-    - 1.02:  added extra set of parentheses to png_jmpbuf() macro; fixed

-              command-line parsing bug

-    - 1.10:  enabled "message window"/console (thanks to David Geldreich)

-    - 2.00:  dual-licensed (added GNU GPL)

-    - 2.01:  fixed improper display of usage screen on PNG error(s)

-

-  ---------------------------------------------------------------------------

-

-      Copyright (c) 1998-2008 Greg Roelofs.  All rights reserved.

-

-      This software is provided "as is," without warranty of any kind,

-      express or implied.  In no event shall the author or contributors

-      be held liable for any damages arising in any way from the use of

-      this software.

-

-      The contents of this file are DUAL-LICENSED.  You may modify and/or

-      redistribute this software according to the terms of one of the

-      following two licenses (at your option):

-

-

-      LICENSE 1 ("BSD-like with advertising clause"):

-

-      Permission is granted to anyone to use this software for any purpose,

-      including commercial applications, and to alter it and redistribute

-      it freely, subject to the following restrictions:

-

-      1. Redistributions of source code must retain the above copyright

-         notice, disclaimer, and this list of conditions.

-      2. Redistributions in binary form must reproduce the above copyright

-         notice, disclaimer, and this list of conditions in the documenta-

-         tion and/or other materials provided with the distribution.

-      3. All advertising materials mentioning features or use of this

-         software must display the following acknowledgment:

-

-            This product includes software developed by Greg Roelofs

-            and contributors for the book, "PNG: The Definitive Guide,"

-            published by O'Reilly and Associates.

-

-

-      LICENSE 2 (GNU GPL v2 or later):

-

-      This program is free software; you can redistribute it and/or modify

-      it under the terms of the GNU General Public License as published by

-      the Free Software Foundation; either version 2 of the License, or

-      (at your option) any later version.

-

-      This program is distributed in the hope that it will be useful,

-      but WITHOUT ANY WARRANTY; without even the implied warranty of

-      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

-      GNU General Public License for more details.

-

-      You should have received a copy of the GNU General Public License

-      along with this program; if not, write to the Free Software Foundation,

-      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

-

-  ---------------------------------------------------------------------------*/

-

-#define PROGNAME  "rpng-win"

-#define LONGNAME  "Simple PNG Viewer for Windows"

-#define VERSION   "2.01 of 16 March 2008"

-

-#include <stdio.h>

-#include <stdlib.h>

-#include <string.h>

-#include <time.h>

-#include <windows.h>

-#ifdef __CYGWIN__

-/* getch replacement. Turns out, we don't really need this,

- * but leave it here if we ever enable any of the uses of

- * _getch in the main code

- */

-#include <unistd.h>

-#include <termio.h>

-#include <sys/ioctl.h>

-int repl_getch( void )

-{

-  char ch;

-  int fd = fileno(stdin);

-  struct termio old_tty, new_tty;

-

-  ioctl(fd, TCGETA, &old_tty);

-  new_tty = old_tty;

-  new_tty.c_lflag &= ~(ICANON | ECHO | ISIG);

-  ioctl(fd, TCSETA, &new_tty);

-  fread(&ch, 1, sizeof(ch), stdin);

-  ioctl(fd, TCSETA, &old_tty);

-

-  return ch;

-}

-#define _getch repl_getch

-#else

-#include <conio.h>      /* only for _getch() */

-#endif

-

-/* #define DEBUG  :  this enables the Trace() macros */

-

-#include "readpng.h"    /* typedefs, common macros, readpng prototypes */

-

-

-/* could just include png.h, but this macro is the only thing we need

- * (name and typedefs changed to local versions); note that side effects

- * only happen with alpha (which could easily be avoided with

- * "ush acopy = (alpha);") */

-

-#define alpha_composite(composite, fg, alpha, bg) {               \

-    ush temp = ((ush)(fg)*(ush)(alpha) +                          \

-                (ush)(bg)*(ush)(255 - (ush)(alpha)) + (ush)128);  \

-    (composite) = (uch)((temp + (temp >> 8)) >> 8);               \

-}

-

-

-/* local prototypes */

-static int        rpng_win_create_window(HINSTANCE hInst, int showmode);

-static int        rpng_win_display_image(void);

-static void       rpng_win_cleanup(void);

-LRESULT CALLBACK  rpng_win_wndproc(HWND, UINT, WPARAM, LPARAM);

-

-

-static char titlebar[1024];

-static char *progname = PROGNAME;

-static char *appname = LONGNAME;

-static char *filename;

-static FILE *infile;

-

-static char *bgstr;

-static uch bg_red=0, bg_green=0, bg_blue=0;

-

-static double display_exponent;

-

-static ulg image_width, image_height, image_rowbytes;

-static int image_channels;

-static uch *image_data;

-

-/* Windows-specific variables */

-static ulg wimage_rowbytes;

-static uch *dib;

-static uch *wimage_data;

-static BITMAPINFOHEADER *bmih;

-

-static HWND global_hwnd;

-

-

-

-

-int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, PSTR cmd, int showmode)

-{

-    char *args[1024];                 /* arbitrary limit, but should suffice */

-    char *p, *q, **argv = args;

-    int argc = 0;

-    int rc, alen, flen;

-    int error = 0;

-    int have_bg = FALSE;

-    double LUT_exponent;              /* just the lookup table */

-    double CRT_exponent = 2.2;        /* just the monitor */

-    double default_display_exponent;  /* whole display system */

-    MSG msg;

-

-

-    filename = (char *)NULL;

-

-#ifndef __CYGWIN__

-    /* First reenable console output, which normally goes to the bit bucket

-     * for windowed apps.  Closing the console window will terminate the

-     * app.  Thanks to David.Geldreich@realviz.com for supplying the magical

-     * incantation. */

-

-    AllocConsole();

-    freopen("CONOUT$", "a", stderr);

-    freopen("CONOUT$", "a", stdout);

-#endif

-

-

-    /* Next set the default value for our display-system exponent, i.e.,

-     * the product of the CRT exponent and the exponent corresponding to

-     * the frame-buffer's lookup table (LUT), if any.  This is not an

-     * exhaustive list of LUT values (e.g., OpenStep has a lot of weird

-     * ones), but it should cover 99% of the current possibilities.  And

-     * yes, these ifdefs are completely wasted in a Windows program... */

-

-#if defined(NeXT)

-    LUT_exponent = 1.0 / 2.2;

-    /*

-    if (some_next_function_that_returns_gamma(&next_gamma))

-        LUT_exponent = 1.0 / next_gamma;

-     */

-#elif defined(sgi)

-    LUT_exponent = 1.0 / 1.7;

-    /* there doesn't seem to be any documented function to get the

-     * "gamma" value, so we do it the hard way */

-    infile = fopen("/etc/config/system.glGammaVal", "r");

-    if (infile) {

-        double sgi_gamma;

-

-        fgets(tmpline, 80, infile);

-        fclose(infile);

-        sgi_gamma = atof(tmpline);

-        if (sgi_gamma > 0.0)

-            LUT_exponent = 1.0 / sgi_gamma;

-    }

-#elif defined(Macintosh)

-    LUT_exponent = 1.8 / 2.61;

-    /*

-    if (some_mac_function_that_returns_gamma(&mac_gamma))

-        LUT_exponent = mac_gamma / 2.61;

-     */

-#else

-    LUT_exponent = 1.0;   /* assume no LUT:  most PCs */

-#endif

-

-    /* the defaults above give 1.0, 1.3, 1.5 and 2.2, respectively: */

-    default_display_exponent = LUT_exponent * CRT_exponent;

-

-

-    /* If the user has set the SCREEN_GAMMA environment variable as suggested

-     * (somewhat imprecisely) in the libpng documentation, use that; otherwise

-     * use the default value we just calculated.  Either way, the user may

-     * override this via a command-line option. */

-

-    if ((p = getenv("SCREEN_GAMMA")) != NULL)

-        display_exponent = atof(p);

-    else

-        display_exponent = default_display_exponent;

-

-

-    /* Windows really hates command lines, so we have to set up our own argv.

-     * Note that we do NOT bother with quoted arguments here, so don't use

-     * filenames with spaces in 'em! */

-

-    argv[argc++] = PROGNAME;

-    p = cmd;

-    for (;;) {

-        if (*p == ' ')

-            while (*++p == ' ')

-                ;

-        /* now p points at the first non-space after some spaces */

-        if (*p == '\0')

-            break;    /* nothing after the spaces:  done */

-        argv[argc++] = q = p;

-        while (*q && *q != ' ')

-            ++q;

-        /* now q points at a space or the end of the string */

-        if (*q == '\0')

-            break;    /* last argv already terminated; quit */

-        *q = '\0';    /* change space to terminator */

-        p = q + 1;

-    }

-    argv[argc] = NULL;   /* terminate the argv array itself */

-

-

-    /* Now parse the command line for options and the PNG filename. */

-

-    while (*++argv && !error) {

-        if (!strncmp(*argv, "-gamma", 2)) {

-            if (!*++argv)

-                ++error;

-            else {

-                display_exponent = atof(*argv);

-                if (display_exponent <= 0.0)

-                    ++error;

-            }

-        } else if (!strncmp(*argv, "-bgcolor", 2)) {

-            if (!*++argv)

-                ++error;

-            else {

-                bgstr = *argv;

-                if (strlen(bgstr) != 7 || bgstr[0] != '#')

-                    ++error;

-                else

-                    have_bg = TRUE;

-            }

-        } else {

-            if (**argv != '-') {

-                filename = *argv;

-                if (argv[1])   /* shouldn't be any more args after filename */

-                    ++error;

-            } else

-                ++error;   /* not expecting any other options */

-        }

-    }

-

-    if (!filename)

-        ++error;

-

-

-    /* print usage screen if any errors up to this point */

-

-    if (error) {

-#ifndef __CYGWIN__

-        int ch;

-#endif

-

-        fprintf(stderr, "\n%s %s:  %s\n\n", PROGNAME, VERSION, appname);

-        readpng_version_info();

-        fprintf(stderr, "\n"

-          "Usage:  %s [-gamma exp] [-bgcolor bg] file.png\n"

-          "    exp \ttransfer-function exponent (``gamma'') of the display\n"

-          "\t\t  system in floating-point format (e.g., ``%.1f''); equal\n"

-          "\t\t  to the product of the lookup-table exponent (varies)\n"

-          "\t\t  and the CRT exponent (usually 2.2); must be positive\n"

-          "    bg  \tdesired background color in 7-character hex RGB format\n"

-          "\t\t  (e.g., ``#ff7700'' for orange:  same as HTML colors);\n"

-          "\t\t  used with transparent images\n"

-          "\nPress Q, Esc or mouse button 1 after image is displayed to quit.\n"

-#ifndef __CYGWIN__

-          "Press Q or Esc to quit this usage screen.\n"

-#endif

-          "\n", PROGNAME, default_display_exponent);

-#ifndef __CYGWIN__

-        do

-            ch = _getch();

-        while (ch != 'q' && ch != 'Q' && ch != 0x1B);

-#endif

-        exit(1);

-    }

-

-

-    if (!(infile = fopen(filename, "rb"))) {

-        fprintf(stderr, PROGNAME ":  can't open PNG file [%s]\n", filename);

-        ++error;

-    } else {

-        if ((rc = readpng_init(infile, &image_width, &image_height)) != 0) {

-            switch (rc) {

-                case 1:

-                    fprintf(stderr, PROGNAME

-                      ":  [%s] is not a PNG file: incorrect signature\n",

-                      filename);

-                    break;

-                case 2:

-                    fprintf(stderr, PROGNAME

-                      ":  [%s] has bad IHDR (libpng longjmp)\n", filename);

-                    break;

-                case 4:

-                    fprintf(stderr, PROGNAME ":  insufficient memory\n");

-                    break;

-                default:

-                    fprintf(stderr, PROGNAME

-                      ":  unknown readpng_init() error\n");

-                    break;

-            }

-            ++error;

-        }

-        if (error)

-            fclose(infile);

-    }

-

-

-    if (error) {

-#ifndef __CYGWIN__

-        int ch;

-#endif

-

-        fprintf(stderr, PROGNAME ":  aborting.\n");

-#ifndef __CYGWIN__

-        do

-            ch = _getch();

-        while (ch != 'q' && ch != 'Q' && ch != 0x1B);

-#endif

-        exit(2);

-    } else {

-        fprintf(stderr, "\n%s %s:  %s\n", PROGNAME, VERSION, appname);

-#ifndef __CYGWIN__

-        fprintf(stderr,

-          "\n   [console window:  closing this window will terminate %s]\n\n",

-          PROGNAME);

-#endif

-    }

-

-

-    /* set the title-bar string, but make sure buffer doesn't overflow */

-

-    alen = strlen(appname);

-    flen = strlen(filename);

-    if (alen + flen + 3 > 1023)

-        sprintf(titlebar, "%s:  ...%s", appname, filename+(alen+flen+6-1023));

-    else

-        sprintf(titlebar, "%s:  %s", appname, filename);

-

-

-    /* if the user didn't specify a background color on the command line,

-     * check for one in the PNG file--if not, the initialized values of 0

-     * (black) will be used */

-

-    if (have_bg) {

-        unsigned r, g, b;   /* this approach quiets compiler warnings */

-

-        sscanf(bgstr+1, "%2x%2x%2x", &r, &g, &b);

-        bg_red   = (uch)r;

-        bg_green = (uch)g;

-        bg_blue  = (uch)b;

-    } else if (readpng_get_bgcolor(&bg_red, &bg_green, &bg_blue) > 1) {

-        readpng_cleanup(TRUE);

-        fprintf(stderr, PROGNAME

-          ":  libpng error while checking for background color\n");

-        exit(2);

-    }

-

-

-    /* do the basic Windows initialization stuff, make the window and fill it

-     * with the background color */

-

-    if (rpng_win_create_window(hInst, showmode))

-        exit(2);

-

-

-    /* decode the image, all at once */

-

-    Trace((stderr, "calling readpng_get_image()\n"))

-    image_data = readpng_get_image(display_exponent, &image_channels,

-      &image_rowbytes);

-    Trace((stderr, "done with readpng_get_image()\n"))

-

-

-    /* done with PNG file, so clean up to minimize memory usage (but do NOT

-     * nuke image_data!) */

-

-    readpng_cleanup(FALSE);

-    fclose(infile);

-

-    if (!image_data) {

-        fprintf(stderr, PROGNAME ":  unable to decode PNG image\n");

-        exit(3);

-    }

-

-

-    /* display image (composite with background if requested) */

-

-    Trace((stderr, "calling rpng_win_display_image()\n"))

-    if (rpng_win_display_image()) {

-        free(image_data);

-        exit(4);

-    }

-    Trace((stderr, "done with rpng_win_display_image()\n"))

-

-

-    /* wait for the user to tell us when to quit */

-

-    printf(

-#ifndef __CYGWIN__

-      "Done.  Press Q, Esc or mouse button 1 (within image window) to quit.\n"

-#else

-      "Done.  Press mouse button 1 (within image window) to quit.\n"

-#endif

-    );

-    fflush(stdout);

-

-    while (GetMessage(&msg, NULL, 0, 0)) {

-        TranslateMessage(&msg);

-        DispatchMessage(&msg);

-    }

-

-

-    /* OK, we're done:  clean up all image and Windows resources and go away */

-

-    rpng_win_cleanup();

-

-    return msg.wParam;

-}

-

-

-

-

-

-static int rpng_win_create_window(HINSTANCE hInst, int showmode)

-{

-    uch *dest;

-    int extra_width, extra_height;

-    ulg i, j;

-    WNDCLASSEX wndclass;

-

-

-/*---------------------------------------------------------------------------

-    Allocate memory for the display-specific version of the image (round up

-    to multiple of 4 for Windows DIB).

-  ---------------------------------------------------------------------------*/

-

-    wimage_rowbytes = ((3*image_width + 3L) >> 2) << 2;

-

-    if (!(dib = (uch *)malloc(sizeof(BITMAPINFOHEADER) +

-                              wimage_rowbytes*image_height)))

-    {

-        return 4;   /* fail */

-    }

-

-/*---------------------------------------------------------------------------

-    Initialize the DIB.  Negative height means to use top-down BMP ordering

-    (must be uncompressed, but that's what we want).  Bit count of 1, 4 or 8

-    implies a colormap of RGBX quads, but 24-bit BMPs just use B,G,R values

-    directly => wimage_data begins immediately after BMP header.

-  ---------------------------------------------------------------------------*/

-

-    memset(dib, 0, sizeof(BITMAPINFOHEADER));

-    bmih = (BITMAPINFOHEADER *)dib;

-    bmih->biSize = sizeof(BITMAPINFOHEADER);

-    bmih->biWidth = image_width;

-    bmih->biHeight = -((long)image_height);

-    bmih->biPlanes = 1;

-    bmih->biBitCount = 24;

-    bmih->biCompression = 0;

-    wimage_data = dib + sizeof(BITMAPINFOHEADER);

-

-/*---------------------------------------------------------------------------

-    Fill in background color (black by default); data are in BGR order.

-  ---------------------------------------------------------------------------*/

-

-    for (j = 0;  j < image_height;  ++j) {

-        dest = wimage_data + j*wimage_rowbytes;

-        for (i = image_width;  i > 0;  --i) {

-            *dest++ = bg_blue;

-            *dest++ = bg_green;

-            *dest++ = bg_red;

-        }

-    }

-

-/*---------------------------------------------------------------------------

-    Set the window parameters.

-  ---------------------------------------------------------------------------*/

-

-    memset(&wndclass, 0, sizeof(wndclass));

-

-    wndclass.cbSize = sizeof(wndclass);

-    wndclass.style = CS_HREDRAW | CS_VREDRAW;

-    wndclass.lpfnWndProc = rpng_win_wndproc;

-    wndclass.hInstance = hInst;

-    wndclass.hIcon = LoadIcon(NULL, IDI_APPLICATION);

-    wndclass.hCursor = LoadCursor(NULL, IDC_ARROW);

-    wndclass.hbrBackground = (HBRUSH)GetStockObject(DKGRAY_BRUSH);

-    wndclass.lpszMenuName = NULL;

-    wndclass.lpszClassName = progname;

-    wndclass.hIconSm = LoadIcon(NULL, IDI_APPLICATION);

-

-    RegisterClassEx(&wndclass);

-

-/*---------------------------------------------------------------------------

-    Finally, create the window.

-  ---------------------------------------------------------------------------*/

-

-    extra_width  = 2*(GetSystemMetrics(SM_CXBORDER) +

-                      GetSystemMetrics(SM_CXDLGFRAME));

-    extra_height = 2*(GetSystemMetrics(SM_CYBORDER) +

-                      GetSystemMetrics(SM_CYDLGFRAME)) +

-                      GetSystemMetrics(SM_CYCAPTION);

-

-    global_hwnd = CreateWindow(progname, titlebar, WS_OVERLAPPEDWINDOW,

-      CW_USEDEFAULT, CW_USEDEFAULT, image_width+extra_width,

-      image_height+extra_height, NULL, NULL, hInst, NULL);

-

-    ShowWindow(global_hwnd, showmode);

-    UpdateWindow(global_hwnd);

-

-    return 0;

-

-} /* end function rpng_win_create_window() */

-

-

-

-

-

-static int rpng_win_display_image()

-{

-    uch *src, *dest;

-    uch r, g, b, a;

-    ulg i, row, lastrow;

-    RECT rect;

-

-

-    Trace((stderr, "beginning display loop (image_channels == %d)\n",

-      image_channels))

-    Trace((stderr, "(width = %ld, rowbytes = %ld, wimage_rowbytes = %d)\n",

-      image_width, image_rowbytes, wimage_rowbytes))

-

-

-/*---------------------------------------------------------------------------

-    Blast image data to buffer.  This whole routine takes place before the

-    message loop begins, so there's no real point in any pseudo-progressive

-    display...

-  ---------------------------------------------------------------------------*/

-

-    for (lastrow = row = 0;  row < image_height;  ++row) {

-        src = image_data + row*image_rowbytes;

-        dest = wimage_data + row*wimage_rowbytes;

-        if (image_channels == 3) {

-            for (i = image_width;  i > 0;  --i) {

-                r = *src++;

-                g = *src++;

-                b = *src++;

-                *dest++ = b;

-                *dest++ = g;   /* note reverse order */

-                *dest++ = r;

-            }

-        } else /* if (image_channels == 4) */ {

-            for (i = image_width;  i > 0;  --i) {

-                r = *src++;

-                g = *src++;

-                b = *src++;

-                a = *src++;

-                if (a == 255) {

-                    *dest++ = b;

-                    *dest++ = g;

-                    *dest++ = r;

-                } else if (a == 0) {

-                    *dest++ = bg_blue;

-                    *dest++ = bg_green;

-                    *dest++ = bg_red;

-                } else {

-                    /* this macro (copied from png.h) composites the

-                     * foreground and background values and puts the

-                     * result into the first argument; there are no

-                     * side effects with the first argument */

-                    alpha_composite(*dest++, b, a, bg_blue);

-                    alpha_composite(*dest++, g, a, bg_green);

-                    alpha_composite(*dest++, r, a, bg_red);

-                }

-            }

-        }

-        /* display after every 16 lines */

-        if (((row+1) & 0xf) == 0) {

-            rect.left = 0L;

-            rect.top = (LONG)lastrow;

-            rect.right = (LONG)image_width;      /* possibly off by one? */

-            rect.bottom = (LONG)lastrow + 16L;   /* possibly off by one? */

-            InvalidateRect(global_hwnd, &rect, FALSE);

-            UpdateWindow(global_hwnd);     /* similar to XFlush() */

-            lastrow = row + 1;

-        }

-    }

-

-    Trace((stderr, "calling final image-flush routine\n"))

-    if (lastrow < image_height) {

-        rect.left = 0L;

-        rect.top = (LONG)lastrow;

-        rect.right = (LONG)image_width;      /* possibly off by one? */

-        rect.bottom = (LONG)image_height;    /* possibly off by one? */

-        InvalidateRect(global_hwnd, &rect, FALSE);

-        UpdateWindow(global_hwnd);     /* similar to XFlush() */

-    }

-

-/*

-    last param determines whether or not background is wiped before paint

-    InvalidateRect(global_hwnd, NULL, TRUE);

-    UpdateWindow(global_hwnd);

- */

-

-    return 0;

-}

-

-

-

-

-

-static void rpng_win_cleanup()

-{

-    if (image_data) {

-        free(image_data);

-        image_data = NULL;

-    }

-

-    if (dib) {

-        free(dib);

-        dib = NULL;

-    }

-}

-

-

-

-

-

-LRESULT CALLBACK rpng_win_wndproc(HWND hwnd, UINT iMsg, WPARAM wP, LPARAM lP)

-{

-    HDC         hdc;

-    PAINTSTRUCT ps;

-    int rc;

-

-    switch (iMsg) {

-        case WM_CREATE:

-            /* one-time processing here, if any */

-            return 0;

-

-        case WM_PAINT:

-            hdc = BeginPaint(hwnd, &ps);

-                    /*                    dest                          */

-            rc = StretchDIBits(hdc, 0, 0, image_width, image_height,

-                    /*                    source                        */

-                                    0, 0, image_width, image_height,

-                                    wimage_data, (BITMAPINFO *)bmih,

-                    /*              iUsage: no clue                     */

-                                    0, SRCCOPY);

-            EndPaint(hwnd, &ps);

-            return 0;

-

-        /* wait for the user to tell us when to quit */

-        case WM_CHAR:

-            switch (wP) {      /* only need one, so ignore repeat count */

-                case 'q':

-                case 'Q':

-                case 0x1B:     /* Esc key */

-                    PostQuitMessage(0);

-            }

-            return 0;

-

-        case WM_LBUTTONDOWN:   /* another way of quitting */

-        case WM_DESTROY:

-            PostQuitMessage(0);

-            return 0;

-    }

-

-    return DefWindowProc(hwnd, iMsg, wP, lP);

-}

+/*---------------------------------------------------------------------------
+
+   rpng - simple PNG display program                             rpng-win.c
+
+   This program decodes and displays PNG images, with gamma correction and
+   optionally with a user-specified background color (in case the image has
+   transparency).  It is very nearly the most basic PNG viewer possible.
+   This version is for 32-bit Windows; it may compile under 16-bit Windows
+   with a little tweaking (or maybe not).
+
+   to do:
+    - handle quoted command-line args (especially filenames with spaces)
+    - have minimum window width:  oh well
+    - use %.1023s to simplify truncation of title-bar string?
+
+  ---------------------------------------------------------------------------
+
+   Changelog:
+    - 1.00:  initial public release
+    - 1.01:  modified to allow abbreviated options; fixed long/ulong mis-
+              match; switched to png_jmpbuf() macro
+    - 1.02:  added extra set of parentheses to png_jmpbuf() macro; fixed
+              command-line parsing bug
+    - 1.10:  enabled "message window"/console (thanks to David Geldreich)
+    - 2.00:  dual-licensed (added GNU GPL)
+    - 2.01:  fixed improper display of usage screen on PNG error(s)
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-2008 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      The contents of this file are DUAL-LICENSED.  You may modify and/or
+      redistribute this software according to the terms of one of the
+      following two licenses (at your option):
+
+
+      LICENSE 1 ("BSD-like with advertising clause"):
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+
+      LICENSE 2 (GNU GPL v2 or later):
+
+      This program is free software; you can redistribute it and/or modify
+      it under the terms of the GNU General Public License as published by
+      the Free Software Foundation; either version 2 of the License, or
+      (at your option) any later version.
+
+      This program is distributed in the hope that it will be useful,
+      but WITHOUT ANY WARRANTY; without even the implied warranty of
+      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+      GNU General Public License for more details.
+
+      You should have received a copy of the GNU General Public License
+      along with this program; if not, write to the Free Software Foundation,
+      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+  ---------------------------------------------------------------------------*/
+
+#define PROGNAME  "rpng-win"
+#define LONGNAME  "Simple PNG Viewer for Windows"
+#define VERSION   "2.01 of 16 March 2008"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <windows.h>
+#ifdef __CYGWIN__
+/* getch replacement. Turns out, we don't really need this,
+ * but leave it here if we ever enable any of the uses of
+ * _getch in the main code
+ */
+#include <unistd.h>
+#include <termio.h>
+#include <sys/ioctl.h>
+int repl_getch( void )
+{
+  char ch;
+  int fd = fileno(stdin);
+  struct termio old_tty, new_tty;
+
+  ioctl(fd, TCGETA, &old_tty);
+  new_tty = old_tty;
+  new_tty.c_lflag &= ~(ICANON | ECHO | ISIG);
+  ioctl(fd, TCSETA, &new_tty);
+  fread(&ch, 1, sizeof(ch), stdin);
+  ioctl(fd, TCSETA, &old_tty);
+
+  return ch;
+}
+#define _getch repl_getch
+#else
+#include <conio.h>      /* only for _getch() */
+#endif
+
+/* #define DEBUG  :  this enables the Trace() macros */
+
+#include "readpng.h"    /* typedefs, common macros, readpng prototypes */
+
+
+/* could just include png.h, but this macro is the only thing we need
+ * (name and typedefs changed to local versions); note that side effects
+ * only happen with alpha (which could easily be avoided with
+ * "ush acopy = (alpha);") */
+
+#define alpha_composite(composite, fg, alpha, bg) {               \
+    ush temp = ((ush)(fg)*(ush)(alpha) +                          \
+                (ush)(bg)*(ush)(255 - (ush)(alpha)) + (ush)128);  \
+    (composite) = (uch)((temp + (temp >> 8)) >> 8);               \
+}
+
+
+/* local prototypes */
+static int        rpng_win_create_window(HINSTANCE hInst, int showmode);
+static int        rpng_win_display_image(void);
+static void       rpng_win_cleanup(void);
+LRESULT CALLBACK  rpng_win_wndproc(HWND, UINT, WPARAM, LPARAM);
+
+
+static char titlebar[1024];
+static char *progname = PROGNAME;
+static char *appname = LONGNAME;
+static char *filename;
+static FILE *infile;
+
+static char *bgstr;
+static uch bg_red=0, bg_green=0, bg_blue=0;
+
+static double display_exponent;
+
+static ulg image_width, image_height, image_rowbytes;
+static int image_channels;
+static uch *image_data;
+
+/* Windows-specific variables */
+static ulg wimage_rowbytes;
+static uch *dib;
+static uch *wimage_data;
+static BITMAPINFOHEADER *bmih;
+
+static HWND global_hwnd;
+
+
+
+
+int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, PSTR cmd, int showmode)
+{
+    char *args[1024];                 /* arbitrary limit, but should suffice */
+    char *p, *q, **argv = args;
+    int argc = 0;
+    int rc, alen, flen;
+    int error = 0;
+    int have_bg = FALSE;
+    double LUT_exponent;              /* just the lookup table */
+    double CRT_exponent = 2.2;        /* just the monitor */
+    double default_display_exponent;  /* whole display system */
+    MSG msg;
+
+
+    filename = (char *)NULL;
+
+#ifndef __CYGWIN__
+    /* First reenable console output, which normally goes to the bit bucket
+     * for windowed apps.  Closing the console window will terminate the
+     * app.  Thanks to David.Geldreich@realviz.com for supplying the magical
+     * incantation. */
+
+    AllocConsole();
+    freopen("CONOUT$", "a", stderr);
+    freopen("CONOUT$", "a", stdout);
+#endif
+
+
+    /* Next set the default value for our display-system exponent, i.e.,
+     * the product of the CRT exponent and the exponent corresponding to
+     * the frame-buffer's lookup table (LUT), if any.  This is not an
+     * exhaustive list of LUT values (e.g., OpenStep has a lot of weird
+     * ones), but it should cover 99% of the current possibilities.  And
+     * yes, these ifdefs are completely wasted in a Windows program... */
+
+#if defined(NeXT)
+    LUT_exponent = 1.0 / 2.2;
+    /*
+    if (some_next_function_that_returns_gamma(&next_gamma))
+        LUT_exponent = 1.0 / next_gamma;
+     */
+#elif defined(sgi)
+    LUT_exponent = 1.0 / 1.7;
+    /* there doesn't seem to be any documented function to get the
+     * "gamma" value, so we do it the hard way */
+    infile = fopen("/etc/config/system.glGammaVal", "r");
+    if (infile) {
+        double sgi_gamma;
+
+        fgets(tmpline, 80, infile);
+        fclose(infile);
+        sgi_gamma = atof(tmpline);
+        if (sgi_gamma > 0.0)
+            LUT_exponent = 1.0 / sgi_gamma;
+    }
+#elif defined(Macintosh)
+    LUT_exponent = 1.8 / 2.61;
+    /*
+    if (some_mac_function_that_returns_gamma(&mac_gamma))
+        LUT_exponent = mac_gamma / 2.61;
+     */
+#else
+    LUT_exponent = 1.0;   /* assume no LUT:  most PCs */
+#endif
+
+    /* the defaults above give 1.0, 1.3, 1.5 and 2.2, respectively: */
+    default_display_exponent = LUT_exponent * CRT_exponent;
+
+
+    /* If the user has set the SCREEN_GAMMA environment variable as suggested
+     * (somewhat imprecisely) in the libpng documentation, use that; otherwise
+     * use the default value we just calculated.  Either way, the user may
+     * override this via a command-line option. */
+
+    if ((p = getenv("SCREEN_GAMMA")) != NULL)
+        display_exponent = atof(p);
+    else
+        display_exponent = default_display_exponent;
+
+
+    /* Windows really hates command lines, so we have to set up our own argv.
+     * Note that we do NOT bother with quoted arguments here, so don't use
+     * filenames with spaces in 'em! */
+
+    argv[argc++] = PROGNAME;
+    p = cmd;
+    for (;;) {
+        if (*p == ' ')
+            while (*++p == ' ')
+                ;
+        /* now p points at the first non-space after some spaces */
+        if (*p == '\0')
+            break;    /* nothing after the spaces:  done */
+        argv[argc++] = q = p;
+        while (*q && *q != ' ')
+            ++q;
+        /* now q points at a space or the end of the string */
+        if (*q == '\0')
+            break;    /* last argv already terminated; quit */
+        *q = '\0';    /* change space to terminator */
+        p = q + 1;
+    }
+    argv[argc] = NULL;   /* terminate the argv array itself */
+
+
+    /* Now parse the command line for options and the PNG filename. */
+
+    while (*++argv && !error) {
+        if (!strncmp(*argv, "-gamma", 2)) {
+            if (!*++argv)
+                ++error;
+            else {
+                display_exponent = atof(*argv);
+                if (display_exponent <= 0.0)
+                    ++error;
+            }
+        } else if (!strncmp(*argv, "-bgcolor", 2)) {
+            if (!*++argv)
+                ++error;
+            else {
+                bgstr = *argv;
+                if (strlen(bgstr) != 7 || bgstr[0] != '#')
+                    ++error;
+                else
+                    have_bg = TRUE;
+            }
+        } else {
+            if (**argv != '-') {
+                filename = *argv;
+                if (argv[1])   /* shouldn't be any more args after filename */
+                    ++error;
+            } else
+                ++error;   /* not expecting any other options */
+        }
+    }
+
+    if (!filename)
+        ++error;
+
+
+    /* print usage screen if any errors up to this point */
+
+    if (error) {
+#ifndef __CYGWIN__
+        int ch;
+#endif
+
+        fprintf(stderr, "\n%s %s:  %s\n\n", PROGNAME, VERSION, appname);
+        readpng_version_info();
+        fprintf(stderr, "\n"
+          "Usage:  %s [-gamma exp] [-bgcolor bg] file.png\n"
+          "    exp \ttransfer-function exponent (``gamma'') of the display\n"
+          "\t\t  system in floating-point format (e.g., ``%.1f''); equal\n"
+          "\t\t  to the product of the lookup-table exponent (varies)\n"
+          "\t\t  and the CRT exponent (usually 2.2); must be positive\n"
+          "    bg  \tdesired background color in 7-character hex RGB format\n"
+          "\t\t  (e.g., ``#ff7700'' for orange:  same as HTML colors);\n"
+          "\t\t  used with transparent images\n"
+          "\nPress Q, Esc or mouse button 1 after image is displayed to quit.\n"
+#ifndef __CYGWIN__
+          "Press Q or Esc to quit this usage screen.\n"
+#endif
+          "\n", PROGNAME, default_display_exponent);
+#ifndef __CYGWIN__
+        do
+            ch = _getch();
+        while (ch != 'q' && ch != 'Q' && ch != 0x1B);
+#endif
+        exit(1);
+    }
+
+
+    if (!(infile = fopen(filename, "rb"))) {
+        fprintf(stderr, PROGNAME ":  can't open PNG file [%s]\n", filename);
+        ++error;
+    } else {
+        if ((rc = readpng_init(infile, &image_width, &image_height)) != 0) {
+            switch (rc) {
+                case 1:
+                    fprintf(stderr, PROGNAME
+                      ":  [%s] is not a PNG file: incorrect signature\n",
+                      filename);
+                    break;
+                case 2:
+                    fprintf(stderr, PROGNAME
+                      ":  [%s] has bad IHDR (libpng longjmp)\n", filename);
+                    break;
+                case 4:
+                    fprintf(stderr, PROGNAME ":  insufficient memory\n");
+                    break;
+                default:
+                    fprintf(stderr, PROGNAME
+                      ":  unknown readpng_init() error\n");
+                    break;
+            }
+            ++error;
+        }
+        if (error)
+            fclose(infile);
+    }
+
+
+    if (error) {
+#ifndef __CYGWIN__
+        int ch;
+#endif
+
+        fprintf(stderr, PROGNAME ":  aborting.\n");
+#ifndef __CYGWIN__
+        do
+            ch = _getch();
+        while (ch != 'q' && ch != 'Q' && ch != 0x1B);
+#endif
+        exit(2);
+    } else {
+        fprintf(stderr, "\n%s %s:  %s\n", PROGNAME, VERSION, appname);
+#ifndef __CYGWIN__
+        fprintf(stderr,
+          "\n   [console window:  closing this window will terminate %s]\n\n",
+          PROGNAME);
+#endif
+    }
+
+
+    /* set the title-bar string, but make sure buffer doesn't overflow */
+
+    alen = strlen(appname);
+    flen = strlen(filename);
+    if (alen + flen + 3 > 1023)
+        sprintf(titlebar, "%s:  ...%s", appname, filename+(alen+flen+6-1023));
+    else
+        sprintf(titlebar, "%s:  %s", appname, filename);
+
+
+    /* if the user didn't specify a background color on the command line,
+     * check for one in the PNG file--if not, the initialized values of 0
+     * (black) will be used */
+
+    if (have_bg) {
+        unsigned r, g, b;   /* this approach quiets compiler warnings */
+
+        sscanf(bgstr+1, "%2x%2x%2x", &r, &g, &b);
+        bg_red   = (uch)r;
+        bg_green = (uch)g;
+        bg_blue  = (uch)b;
+    } else if (readpng_get_bgcolor(&bg_red, &bg_green, &bg_blue) > 1) {
+        readpng_cleanup(TRUE);
+        fprintf(stderr, PROGNAME
+          ":  libpng error while checking for background color\n");
+        exit(2);
+    }
+
+
+    /* do the basic Windows initialization stuff, make the window and fill it
+     * with the background color */
+
+    if (rpng_win_create_window(hInst, showmode))
+        exit(2);
+
+
+    /* decode the image, all at once */
+
+    Trace((stderr, "calling readpng_get_image()\n"))
+    image_data = readpng_get_image(display_exponent, &image_channels,
+      &image_rowbytes);
+    Trace((stderr, "done with readpng_get_image()\n"))
+
+
+    /* done with PNG file, so clean up to minimize memory usage (but do NOT
+     * nuke image_data!) */
+
+    readpng_cleanup(FALSE);
+    fclose(infile);
+
+    if (!image_data) {
+        fprintf(stderr, PROGNAME ":  unable to decode PNG image\n");
+        exit(3);
+    }
+
+
+    /* display image (composite with background if requested) */
+
+    Trace((stderr, "calling rpng_win_display_image()\n"))
+    if (rpng_win_display_image()) {
+        free(image_data);
+        exit(4);
+    }
+    Trace((stderr, "done with rpng_win_display_image()\n"))
+
+
+    /* wait for the user to tell us when to quit */
+
+    printf(
+#ifndef __CYGWIN__
+      "Done.  Press Q, Esc or mouse button 1 (within image window) to quit.\n"
+#else
+      "Done.  Press mouse button 1 (within image window) to quit.\n"
+#endif
+    );
+    fflush(stdout);
+
+    while (GetMessage(&msg, NULL, 0, 0)) {
+        TranslateMessage(&msg);
+        DispatchMessage(&msg);
+    }
+
+
+    /* OK, we're done:  clean up all image and Windows resources and go away */
+
+    rpng_win_cleanup();
+
+    return msg.wParam;
+}
+
+
+
+
+
+static int rpng_win_create_window(HINSTANCE hInst, int showmode)
+{
+    uch *dest;
+    int extra_width, extra_height;
+    ulg i, j;
+    WNDCLASSEX wndclass;
+
+
+/*---------------------------------------------------------------------------
+    Allocate memory for the display-specific version of the image (round up
+    to multiple of 4 for Windows DIB).
+  ---------------------------------------------------------------------------*/
+
+    wimage_rowbytes = ((3*image_width + 3L) >> 2) << 2;
+
+    if (!(dib = (uch *)malloc(sizeof(BITMAPINFOHEADER) +
+                              wimage_rowbytes*image_height)))
+    {
+        return 4;   /* fail */
+    }
+
+/*---------------------------------------------------------------------------
+    Initialize the DIB.  Negative height means to use top-down BMP ordering
+    (must be uncompressed, but that's what we want).  Bit count of 1, 4 or 8
+    implies a colormap of RGBX quads, but 24-bit BMPs just use B,G,R values
+    directly => wimage_data begins immediately after BMP header.
+  ---------------------------------------------------------------------------*/
+
+    memset(dib, 0, sizeof(BITMAPINFOHEADER));
+    bmih = (BITMAPINFOHEADER *)dib;
+    bmih->biSize = sizeof(BITMAPINFOHEADER);
+    bmih->biWidth = image_width;
+    bmih->biHeight = -((long)image_height);
+    bmih->biPlanes = 1;
+    bmih->biBitCount = 24;
+    bmih->biCompression = 0;
+    wimage_data = dib + sizeof(BITMAPINFOHEADER);
+
+/*---------------------------------------------------------------------------
+    Fill in background color (black by default); data are in BGR order.
+  ---------------------------------------------------------------------------*/
+
+    for (j = 0;  j < image_height;  ++j) {
+        dest = wimage_data + j*wimage_rowbytes;
+        for (i = image_width;  i > 0;  --i) {
+            *dest++ = bg_blue;
+            *dest++ = bg_green;
+            *dest++ = bg_red;
+        }
+    }
+
+/*---------------------------------------------------------------------------
+    Set the window parameters.
+  ---------------------------------------------------------------------------*/
+
+    memset(&wndclass, 0, sizeof(wndclass));
+
+    wndclass.cbSize = sizeof(wndclass);
+    wndclass.style = CS_HREDRAW | CS_VREDRAW;
+    wndclass.lpfnWndProc = rpng_win_wndproc;
+    wndclass.hInstance = hInst;
+    wndclass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
+    wndclass.hCursor = LoadCursor(NULL, IDC_ARROW);
+    wndclass.hbrBackground = (HBRUSH)GetStockObject(DKGRAY_BRUSH);
+    wndclass.lpszMenuName = NULL;
+    wndclass.lpszClassName = progname;
+    wndclass.hIconSm = LoadIcon(NULL, IDI_APPLICATION);
+
+    RegisterClassEx(&wndclass);
+
+/*---------------------------------------------------------------------------
+    Finally, create the window.
+  ---------------------------------------------------------------------------*/
+
+    extra_width  = 2*(GetSystemMetrics(SM_CXBORDER) +
+                      GetSystemMetrics(SM_CXDLGFRAME));
+    extra_height = 2*(GetSystemMetrics(SM_CYBORDER) +
+                      GetSystemMetrics(SM_CYDLGFRAME)) +
+                      GetSystemMetrics(SM_CYCAPTION);
+
+    global_hwnd = CreateWindow(progname, titlebar, WS_OVERLAPPEDWINDOW,
+      CW_USEDEFAULT, CW_USEDEFAULT, image_width+extra_width,
+      image_height+extra_height, NULL, NULL, hInst, NULL);
+
+    ShowWindow(global_hwnd, showmode);
+    UpdateWindow(global_hwnd);
+
+    return 0;
+
+} /* end function rpng_win_create_window() */
+
+
+
+
+
+static int rpng_win_display_image()
+{
+    uch *src, *dest;
+    uch r, g, b, a;
+    ulg i, row, lastrow;
+    RECT rect;
+
+
+    Trace((stderr, "beginning display loop (image_channels == %d)\n",
+      image_channels))
+    Trace((stderr, "(width = %ld, rowbytes = %ld, wimage_rowbytes = %d)\n",
+      image_width, image_rowbytes, wimage_rowbytes))
+
+
+/*---------------------------------------------------------------------------
+    Blast image data to buffer.  This whole routine takes place before the
+    message loop begins, so there's no real point in any pseudo-progressive
+    display...
+  ---------------------------------------------------------------------------*/
+
+    for (lastrow = row = 0;  row < image_height;  ++row) {
+        src = image_data + row*image_rowbytes;
+        dest = wimage_data + row*wimage_rowbytes;
+        if (image_channels == 3) {
+            for (i = image_width;  i > 0;  --i) {
+                r = *src++;
+                g = *src++;
+                b = *src++;
+                *dest++ = b;
+                *dest++ = g;   /* note reverse order */
+                *dest++ = r;
+            }
+        } else /* if (image_channels == 4) */ {
+            for (i = image_width;  i > 0;  --i) {
+                r = *src++;
+                g = *src++;
+                b = *src++;
+                a = *src++;
+                if (a == 255) {
+                    *dest++ = b;
+                    *dest++ = g;
+                    *dest++ = r;
+                } else if (a == 0) {
+                    *dest++ = bg_blue;
+                    *dest++ = bg_green;
+                    *dest++ = bg_red;
+                } else {
+                    /* this macro (copied from png.h) composites the
+                     * foreground and background values and puts the
+                     * result into the first argument; there are no
+                     * side effects with the first argument */
+                    alpha_composite(*dest++, b, a, bg_blue);
+                    alpha_composite(*dest++, g, a, bg_green);
+                    alpha_composite(*dest++, r, a, bg_red);
+                }
+            }
+        }
+        /* display after every 16 lines */
+        if (((row+1) & 0xf) == 0) {
+            rect.left = 0L;
+            rect.top = (LONG)lastrow;
+            rect.right = (LONG)image_width;      /* possibly off by one? */
+            rect.bottom = (LONG)lastrow + 16L;   /* possibly off by one? */
+            InvalidateRect(global_hwnd, &rect, FALSE);
+            UpdateWindow(global_hwnd);     /* similar to XFlush() */
+            lastrow = row + 1;
+        }
+    }
+
+    Trace((stderr, "calling final image-flush routine\n"))
+    if (lastrow < image_height) {
+        rect.left = 0L;
+        rect.top = (LONG)lastrow;
+        rect.right = (LONG)image_width;      /* possibly off by one? */
+        rect.bottom = (LONG)image_height;    /* possibly off by one? */
+        InvalidateRect(global_hwnd, &rect, FALSE);
+        UpdateWindow(global_hwnd);     /* similar to XFlush() */
+    }
+
+/*
+    last param determines whether or not background is wiped before paint
+    InvalidateRect(global_hwnd, NULL, TRUE);
+    UpdateWindow(global_hwnd);
+ */
+
+    return 0;
+}
+
+
+
+
+
+static void rpng_win_cleanup()
+{
+    if (image_data) {
+        free(image_data);
+        image_data = NULL;
+    }
+
+    if (dib) {
+        free(dib);
+        dib = NULL;
+    }
+}
+
+
+
+
+
+LRESULT CALLBACK rpng_win_wndproc(HWND hwnd, UINT iMsg, WPARAM wP, LPARAM lP)
+{
+    HDC         hdc;
+    PAINTSTRUCT ps;
+    int rc;
+
+    switch (iMsg) {
+        case WM_CREATE:
+            /* one-time processing here, if any */
+            return 0;
+
+        case WM_PAINT:
+            hdc = BeginPaint(hwnd, &ps);
+                    /*                    dest                          */
+            rc = StretchDIBits(hdc, 0, 0, image_width, image_height,
+                    /*                    source                        */
+                                    0, 0, image_width, image_height,
+                                    wimage_data, (BITMAPINFO *)bmih,
+                    /*              iUsage: no clue                     */
+                                    0, SRCCOPY);
+            EndPaint(hwnd, &ps);
+            return 0;
+
+        /* wait for the user to tell us when to quit */
+        case WM_CHAR:
+            switch (wP) {      /* only need one, so ignore repeat count */
+                case 'q':
+                case 'Q':
+                case 0x1B:     /* Esc key */
+                    PostQuitMessage(0);
+            }
+            return 0;
+
+        case WM_LBUTTONDOWN:   /* another way of quitting */
+        case WM_DESTROY:
+            PostQuitMessage(0);
+            return 0;
+    }
+
+    return DefWindowProc(hwnd, iMsg, wP, lP);
+}
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/rpng-x.c b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/rpng-x.c
index fc8be88..6d10e1b 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/rpng-x.c
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/rpng-x.c
@@ -1,904 +1,904 @@
-/*---------------------------------------------------------------------------

-

-   rpng - simple PNG display program                               rpng-x.c

-

-   This program decodes and displays PNG images, with gamma correction and

-   optionally with a user-specified background color (in case the image has

-   transparency).  It is very nearly the most basic PNG viewer possible.

-   This version is for the X Window System (tested by author under Unix and

-   by Martin Zinser under OpenVMS; may work under OS/2 with some tweaking).

-

-   to do:

-    - 8-bit (colormapped) X support

-    - use %.1023s to simplify truncation of title-bar string?

-

-  ---------------------------------------------------------------------------

-

-   Changelog:

-    - 1.01:  initial public release

-    - 1.02:  modified to allow abbreviated options; fixed long/ulong mis-

-              match; switched to png_jmpbuf() macro

-    - 1.10:  added support for non-default visuals; fixed X pixel-conversion

-    - 1.11:  added extra set of parentheses to png_jmpbuf() macro; fixed

-              command-line parsing bug

-    - 1.12:  fixed some small X memory leaks (thanks to François Petitjean)

-    - 1.13:  fixed XFreeGC() crash bug (thanks to Patrick Welche)

-    - 1.14:  added support for X resources (thanks to Gerhard Niklasch)

-    - 2.00:  dual-licensed (added GNU GPL)

-    - 2.01:  fixed improper display of usage screen on PNG error(s)

-

-  ---------------------------------------------------------------------------

-

-      Copyright (c) 1998-2008 Greg Roelofs.  All rights reserved.

-

-      This software is provided "as is," without warranty of any kind,

-      express or implied.  In no event shall the author or contributors

-      be held liable for any damages arising in any way from the use of

-      this software.

-

-      The contents of this file are DUAL-LICENSED.  You may modify and/or

-      redistribute this software according to the terms of one of the

-      following two licenses (at your option):

-

-

-      LICENSE 1 ("BSD-like with advertising clause"):

-

-      Permission is granted to anyone to use this software for any purpose,

-      including commercial applications, and to alter it and redistribute

-      it freely, subject to the following restrictions:

-

-      1. Redistributions of source code must retain the above copyright

-         notice, disclaimer, and this list of conditions.

-      2. Redistributions in binary form must reproduce the above copyright

-         notice, disclaimer, and this list of conditions in the documenta-

-         tion and/or other materials provided with the distribution.

-      3. All advertising materials mentioning features or use of this

-         software must display the following acknowledgment:

-

-            This product includes software developed by Greg Roelofs

-            and contributors for the book, "PNG: The Definitive Guide,"

-            published by O'Reilly and Associates.

-

-

-      LICENSE 2 (GNU GPL v2 or later):

-

-      This program is free software; you can redistribute it and/or modify

-      it under the terms of the GNU General Public License as published by

-      the Free Software Foundation; either version 2 of the License, or

-      (at your option) any later version.

-

-      This program is distributed in the hope that it will be useful,

-      but WITHOUT ANY WARRANTY; without even the implied warranty of

-      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

-      GNU General Public License for more details.

-

-      You should have received a copy of the GNU General Public License

-      along with this program; if not, write to the Free Software Foundation,

-      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

-

-  ---------------------------------------------------------------------------*/

-

-#define PROGNAME  "rpng-x"

-#define LONGNAME  "Simple PNG Viewer for X"

-#define VERSION   "2.01 of 16 March 2008"

-#define RESNAME   "rpng"        /* our X resource application name */

-#define RESCLASS  "Rpng"        /* our X resource class name */

-

-#include <stdio.h>

-#include <stdlib.h>

-#include <string.h>

-#include <time.h>

-#include <X11/Xlib.h>

-#include <X11/Xutil.h>

-#include <X11/Xos.h>

-#include <X11/keysym.h>

-

-/* #define DEBUG  :  this enables the Trace() macros */

-

-#include "readpng.h"   /* typedefs, common macros, readpng prototypes */

-

-

-/* could just include png.h, but this macro is the only thing we need

- * (name and typedefs changed to local versions); note that side effects

- * only happen with alpha (which could easily be avoided with

- * "ush acopy = (alpha);") */

-

-#define alpha_composite(composite, fg, alpha, bg) {               \

-    ush temp = ((ush)(fg)*(ush)(alpha) +                          \

-                (ush)(bg)*(ush)(255 - (ush)(alpha)) + (ush)128);  \

-    (composite) = (uch)((temp + (temp >> 8)) >> 8);               \

-}

-

-

-/* local prototypes */

-static int  rpng_x_create_window(void);

-static int  rpng_x_display_image(void);

-static void rpng_x_cleanup(void);

-static int  rpng_x_msb(ulg u32val);

-

-

-static char titlebar[1024], *window_name = titlebar;

-static char *appname = LONGNAME;

-static char *icon_name = PROGNAME;

-static char *res_name = RESNAME;

-static char *res_class = RESCLASS;

-static char *filename;

-static FILE *infile;

-

-static char *bgstr;

-static uch bg_red=0, bg_green=0, bg_blue=0;

-

-static double display_exponent;

-

-static ulg image_width, image_height, image_rowbytes;

-static int image_channels;

-static uch *image_data;

-

-/* X-specific variables */

-static char *displayname;

-static XImage *ximage;

-static Display *display;

-static int depth;

-static Visual *visual;

-static XVisualInfo *visual_list;

-static int RShift, GShift, BShift;

-static ulg RMask, GMask, BMask;

-static Window window;

-static GC gc;

-static Colormap colormap;

-

-static int have_nondefault_visual = FALSE;

-static int have_colormap = FALSE;

-static int have_window = FALSE;

-static int have_gc = FALSE;

-/*

-ulg numcolors=0, pixels[256];

-ush reds[256], greens[256], blues[256];

- */

-

-

-

-

-int main(int argc, char **argv)

-{

-#ifdef sgi

-    char tmpline[80];

-#endif

-    char *p;

-    int rc, alen, flen;

-    int error = 0;

-    int have_bg = FALSE;

-    double LUT_exponent;               /* just the lookup table */

-    double CRT_exponent = 2.2;         /* just the monitor */

-    double default_display_exponent;   /* whole display system */

-    XEvent e;

-    KeySym k;

-

-

-    displayname = (char *)NULL;

-    filename = (char *)NULL;

-

-

-    /* First set the default value for our display-system exponent, i.e.,

-     * the product of the CRT exponent and the exponent corresponding to

-     * the frame-buffer's lookup table (LUT), if any.  This is not an

-     * exhaustive list of LUT values (e.g., OpenStep has a lot of weird

-     * ones), but it should cover 99% of the current possibilities. */

-

-#if defined(NeXT)

-    LUT_exponent = 1.0 / 2.2;

-    /*

-    if (some_next_function_that_returns_gamma(&next_gamma))

-        LUT_exponent = 1.0 / next_gamma;

-     */

-#elif defined(sgi)

-    LUT_exponent = 1.0 / 1.7;

-    /* there doesn't seem to be any documented function to get the

-     * "gamma" value, so we do it the hard way */

-    infile = fopen("/etc/config/system.glGammaVal", "r");

-    if (infile) {

-        double sgi_gamma;

-

-        fgets(tmpline, 80, infile);

-        fclose(infile);

-        sgi_gamma = atof(tmpline);

-        if (sgi_gamma > 0.0)

-            LUT_exponent = 1.0 / sgi_gamma;

-    }

-#elif defined(Macintosh)

-    LUT_exponent = 1.8 / 2.61;

-    /*

-    if (some_mac_function_that_returns_gamma(&mac_gamma))

-        LUT_exponent = mac_gamma / 2.61;

-     */

-#else

-    LUT_exponent = 1.0;   /* assume no LUT:  most PCs */

-#endif

-

-    /* the defaults above give 1.0, 1.3, 1.5 and 2.2, respectively: */

-    default_display_exponent = LUT_exponent * CRT_exponent;

-

-

-    /* If the user has set the SCREEN_GAMMA environment variable as suggested

-     * (somewhat imprecisely) in the libpng documentation, use that; otherwise

-     * use the default value we just calculated.  Either way, the user may

-     * override this via a command-line option. */

-

-    if ((p = getenv("SCREEN_GAMMA")) != NULL)

-        display_exponent = atof(p);

-    else

-        display_exponent = default_display_exponent;

-

-

-    /* Now parse the command line for options and the PNG filename. */

-

-    while (*++argv && !error) {

-        if (!strncmp(*argv, "-display", 2)) {

-            if (!*++argv)

-                ++error;

-            else

-                displayname = *argv;

-        } else if (!strncmp(*argv, "-gamma", 2)) {

-            if (!*++argv)

-                ++error;

-            else {

-                display_exponent = atof(*argv);

-                if (display_exponent <= 0.0)

-                    ++error;

-            }

-        } else if (!strncmp(*argv, "-bgcolor", 2)) {

-            if (!*++argv)

-                ++error;

-            else {

-                bgstr = *argv;

-                if (strlen(bgstr) != 7 || bgstr[0] != '#')

-                    ++error;

-                else

-                    have_bg = TRUE;

-            }

-        } else {

-            if (**argv != '-') {

-                filename = *argv;

-                if (argv[1])   /* shouldn't be any more args after filename */

-                    ++error;

-            } else

-                ++error;   /* not expecting any other options */

-        }

-    }

-

-    if (!filename)

-        ++error;

-

-

-    /* print usage screen if any errors up to this point */

-

-    if (error) {

-        fprintf(stderr, "\n%s %s:  %s\n", PROGNAME, VERSION, appname);

-        readpng_version_info();

-        fprintf(stderr, "\n"

-          "Usage:  %s [-display xdpy] [-gamma exp] [-bgcolor bg] file.png\n"

-          "    xdpy\tname of the target X display (e.g., ``hostname:0'')\n"

-          "    exp \ttransfer-function exponent (``gamma'') of the display\n"

-          "\t\t  system in floating-point format (e.g., ``%.1f''); equal\n"

-          "\t\t  to the product of the lookup-table exponent (varies)\n"

-          "\t\t  and the CRT exponent (usually 2.2); must be positive\n"

-          "    bg  \tdesired background color in 7-character hex RGB format\n"

-          "\t\t  (e.g., ``#ff7700'' for orange:  same as HTML colors);\n"

-          "\t\t  used with transparent images\n"

-          "\nPress Q, Esc or mouse button 1 (within image window, after image\n"

-          "is displayed) to quit.\n"

-          "\n", PROGNAME, default_display_exponent);

-        exit(1);

-    }

-

-

-    if (!(infile = fopen(filename, "rb"))) {

-        fprintf(stderr, PROGNAME ":  can't open PNG file [%s]\n", filename);

-        ++error;

-    } else {

-        if ((rc = readpng_init(infile, &image_width, &image_height)) != 0) {

-            switch (rc) {

-                case 1:

-                    fprintf(stderr, PROGNAME

-                      ":  [%s] is not a PNG file: incorrect signature\n",

-                      filename);

-                    break;

-                case 2:

-                    fprintf(stderr, PROGNAME

-                      ":  [%s] has bad IHDR (libpng longjmp)\n", filename);

-                    break;

-                case 4:

-                    fprintf(stderr, PROGNAME ":  insufficient memory\n");

-                    break;

-                default:

-                    fprintf(stderr, PROGNAME

-                      ":  unknown readpng_init() error\n");

-                    break;

-            }

-            ++error;

-        } else {

-            display = XOpenDisplay(displayname);

-            if (!display) {

-                readpng_cleanup(TRUE);

-                fprintf(stderr, PROGNAME ":  can't open X display [%s]\n",

-                  displayname? displayname : "default");

-                ++error;

-            }

-        }

-        if (error)

-            fclose(infile);

-    }

-

-

-    if (error) {

-        fprintf(stderr, PROGNAME ":  aborting.\n");

-        exit(2);

-    }

-

-

-    /* set the title-bar string, but make sure buffer doesn't overflow */

-

-    alen = strlen(appname);

-    flen = strlen(filename);

-    if (alen + flen + 3 > 1023)

-        sprintf(titlebar, "%s:  ...%s", appname, filename+(alen+flen+6-1023));

-    else

-        sprintf(titlebar, "%s:  %s", appname, filename);

-

-

-    /* if the user didn't specify a background color on the command line,

-     * check for one in the PNG file--if not, the initialized values of 0

-     * (black) will be used */

-

-    if (have_bg) {

-        unsigned r, g, b;   /* this approach quiets compiler warnings */

-

-        sscanf(bgstr+1, "%2x%2x%2x", &r, &g, &b);

-        bg_red   = (uch)r;

-        bg_green = (uch)g;

-        bg_blue  = (uch)b;

-    } else if (readpng_get_bgcolor(&bg_red, &bg_green, &bg_blue) > 1) {

-        readpng_cleanup(TRUE);

-        fprintf(stderr, PROGNAME

-          ":  libpng error while checking for background color\n");

-        exit(2);

-    }

-

-

-    /* do the basic X initialization stuff, make the window and fill it

-     * with the background color */

-

-    if (rpng_x_create_window())

-        exit(2);

-

-

-    /* decode the image, all at once */

-

-    Trace((stderr, "calling readpng_get_image()\n"))

-    image_data = readpng_get_image(display_exponent, &image_channels,

-      &image_rowbytes);

-    Trace((stderr, "done with readpng_get_image()\n"))

-

-

-    /* done with PNG file, so clean up to minimize memory usage (but do NOT

-     * nuke image_data!) */

-

-    readpng_cleanup(FALSE);

-    fclose(infile);

-

-    if (!image_data) {

-        fprintf(stderr, PROGNAME ":  unable to decode PNG image\n");

-        exit(3);

-    }

-

-

-    /* display image (composite with background if requested) */

-

-    Trace((stderr, "calling rpng_x_display_image()\n"))

-    if (rpng_x_display_image()) {

-        free(image_data);

-        exit(4);

-    }

-    Trace((stderr, "done with rpng_x_display_image()\n"))

-

-

-    /* wait for the user to tell us when to quit */

-

-    printf(

-      "Done.  Press Q, Esc or mouse button 1 (within image window) to quit.\n");

-    fflush(stdout);

-

-    do

-        XNextEvent(display, &e);

-    while (!(e.type == ButtonPress && e.xbutton.button == Button1) &&

-           !(e.type == KeyPress &&    /*  v--- or 1 for shifted keys */

-             ((k = XLookupKeysym(&e.xkey, 0)) == XK_q || k == XK_Escape) ));

-

-

-    /* OK, we're done:  clean up all image and X resources and go away */

-

-    rpng_x_cleanup();

-

-    return 0;

-}

-

-

-

-

-

-static int rpng_x_create_window(void)

-{

-    uch *xdata;

-    int need_colormap = FALSE;

-    int screen, pad;

-    ulg bg_pixel = 0L;

-    ulg attrmask;

-    Window root;

-    XEvent e;

-    XGCValues gcvalues;

-    XSetWindowAttributes attr;

-    XTextProperty windowName, *pWindowName = &windowName;

-    XTextProperty iconName, *pIconName = &iconName;

-    XVisualInfo visual_info;

-    XSizeHints *size_hints;

-    XWMHints *wm_hints;

-    XClassHint *class_hints;

-

-

-    screen = DefaultScreen(display);

-    depth = DisplayPlanes(display, screen);

-    root = RootWindow(display, screen);

-

-#ifdef DEBUG

-    XSynchronize(display, True);

-#endif

-

-#if 0

-/* GRR:  add 8-bit support */

-    if (/* depth != 8 && */ depth != 16 && depth != 24 && depth != 32) {

-        fprintf(stderr,

-          "screen depth %d not supported (only 16-, 24- or 32-bit TrueColor)\n",

-          depth);

-        return 2;

-    }

-

-    XMatchVisualInfo(display, screen, depth,

-      (depth == 8)? PseudoColor : TrueColor, &visual_info);

-    visual = visual_info.visual;

-#else

-    if (depth != 16 && depth != 24 && depth != 32) {

-        int visuals_matched = 0;

-

-        Trace((stderr, "default depth is %d:  checking other visuals\n",

-          depth))

-

-        /* 24-bit first */

-        visual_info.screen = screen;

-        visual_info.depth = 24;

-        visual_list = XGetVisualInfo(display,

-          VisualScreenMask | VisualDepthMask, &visual_info, &visuals_matched);

-        if (visuals_matched == 0) {

-/* GRR:  add 15-, 16- and 32-bit TrueColor visuals (also DirectColor?) */

-            fprintf(stderr, "default screen depth %d not supported, and no"

-              " 24-bit visuals found\n", depth);

-            return 2;

-        }

-        Trace((stderr, "XGetVisualInfo() returned %d 24-bit visuals\n",

-          visuals_matched))

-        visual = visual_list[0].visual;

-        depth = visual_list[0].depth;

-/*

-        colormap_size = visual_list[0].colormap_size;

-        visual_class = visual->class;

-        visualID = XVisualIDFromVisual(visual);

- */

-        have_nondefault_visual = TRUE;

-        need_colormap = TRUE;

-    } else {

-        XMatchVisualInfo(display, screen, depth, TrueColor, &visual_info);

-        visual = visual_info.visual;

-    }

-#endif

-

-    RMask = visual->red_mask;

-    GMask = visual->green_mask;

-    BMask = visual->blue_mask;

-

-/* GRR:  add/check 8-bit support */

-    if (depth == 8 || need_colormap) {

-        colormap = XCreateColormap(display, root, visual, AllocNone);

-        if (!colormap) {

-            fprintf(stderr, "XCreateColormap() failed\n");

-            return 2;

-        }

-        have_colormap = TRUE;

-    }

-    if (depth == 15 || depth == 16) {

-        RShift = 15 - rpng_x_msb(RMask);    /* these are right-shifts */

-        GShift = 15 - rpng_x_msb(GMask);

-        BShift = 15 - rpng_x_msb(BMask);

-    } else if (depth > 16) {

-#define NO_24BIT_MASKS

-#ifdef NO_24BIT_MASKS

-        RShift = rpng_x_msb(RMask) - 7;     /* these are left-shifts */

-        GShift = rpng_x_msb(GMask) - 7;

-        BShift = rpng_x_msb(BMask) - 7;

-#else

-        RShift = 7 - rpng_x_msb(RMask);     /* these are right-shifts, too */

-        GShift = 7 - rpng_x_msb(GMask);

-        BShift = 7 - rpng_x_msb(BMask);

-#endif

-    }

-    if (depth >= 15 && (RShift < 0 || GShift < 0 || BShift < 0)) {

-        fprintf(stderr, "rpng internal logic error:  negative X shift(s)!\n");

-        return 2;

-    }

-

-/*---------------------------------------------------------------------------

-    Finally, create the window.

-  ---------------------------------------------------------------------------*/

-

-    attr.backing_store = Always;

-    attr.event_mask = ExposureMask | KeyPressMask | ButtonPressMask;

-    attrmask = CWBackingStore | CWEventMask;

-    if (have_nondefault_visual) {

-        attr.colormap = colormap;

-        attr.background_pixel = 0;

-        attr.border_pixel = 1;

-        attrmask |= CWColormap | CWBackPixel | CWBorderPixel;

-    }

-

-    window = XCreateWindow(display, root, 0, 0, image_width, image_height, 0,

-      depth, InputOutput, visual, attrmask, &attr);

-

-    if (window == None) {

-        fprintf(stderr, "XCreateWindow() failed\n");

-        return 2;

-    } else

-        have_window = TRUE;

-

-    if (depth == 8)

-        XSetWindowColormap(display, window, colormap);

-

-    if (!XStringListToTextProperty(&window_name, 1, pWindowName))

-        pWindowName = NULL;

-    if (!XStringListToTextProperty(&icon_name, 1, pIconName))

-        pIconName = NULL;

-

-    /* OK if any hints allocation fails; XSetWMProperties() allows NULLs */

-

-    if ((size_hints = XAllocSizeHints()) != NULL) {

-        /* window will not be resizable */

-        size_hints->flags = PMinSize | PMaxSize;

-        size_hints->min_width = size_hints->max_width = (int)image_width;

-        size_hints->min_height = size_hints->max_height = (int)image_height;

-    }

-

-    if ((wm_hints = XAllocWMHints()) != NULL) {

-        wm_hints->initial_state = NormalState;

-        wm_hints->input = True;

-     /* wm_hints->icon_pixmap = icon_pixmap; */

-        wm_hints->flags = StateHint | InputHint  /* | IconPixmapHint */ ;

-    }

-

-    if ((class_hints = XAllocClassHint()) != NULL) {

-        class_hints->res_name = res_name;

-        class_hints->res_class = res_class;

-    }

-

-    XSetWMProperties(display, window, pWindowName, pIconName, NULL, 0,

-      size_hints, wm_hints, class_hints);

-

-    /* various properties and hints no longer needed; free memory */

-    if (pWindowName)

-       XFree(pWindowName->value);

-    if (pIconName)

-       XFree(pIconName->value);

-    if (size_hints)

-        XFree(size_hints);

-    if (wm_hints)

-       XFree(wm_hints);

-    if (class_hints)

-       XFree(class_hints);

-

-    XMapWindow(display, window);

-

-    gc = XCreateGC(display, window, 0, &gcvalues);

-    have_gc = TRUE;

-

-/*---------------------------------------------------------------------------

-    Fill window with the specified background color.

-  ---------------------------------------------------------------------------*/

-

-    if (depth == 24 || depth == 32) {

-        bg_pixel = ((ulg)bg_red   << RShift) |

-                   ((ulg)bg_green << GShift) |

-                   ((ulg)bg_blue  << BShift);

-    } else if (depth == 16) {

-        bg_pixel = ((((ulg)bg_red   << 8) >> RShift) & RMask) |

-                   ((((ulg)bg_green << 8) >> GShift) & GMask) |

-                   ((((ulg)bg_blue  << 8) >> BShift) & BMask);

-    } else /* depth == 8 */ {

-

-        /* GRR:  add 8-bit support */

-

-    }

-

-    XSetForeground(display, gc, bg_pixel);

-    XFillRectangle(display, window, gc, 0, 0, image_width, image_height);

-

-/*---------------------------------------------------------------------------

-    Wait for first Expose event to do any drawing, then flush.

-  ---------------------------------------------------------------------------*/

-

-    do

-        XNextEvent(display, &e);

-    while (e.type != Expose || e.xexpose.count);

-

-    XFlush(display);

-

-/*---------------------------------------------------------------------------

-    Allocate memory for the X- and display-specific version of the image.

-  ---------------------------------------------------------------------------*/

-

-    if (depth == 24 || depth == 32) {

-        xdata = (uch *)malloc(4*image_width*image_height);

-        pad = 32;

-    } else if (depth == 16) {

-        xdata = (uch *)malloc(2*image_width*image_height);

-        pad = 16;

-    } else /* depth == 8 */ {

-        xdata = (uch *)malloc(image_width*image_height);

-        pad = 8;

-    }

-

-    if (!xdata) {

-        fprintf(stderr, PROGNAME ":  unable to allocate image memory\n");

-        return 4;

-    }

-

-    ximage = XCreateImage(display, visual, depth, ZPixmap, 0,

-      (char *)xdata, image_width, image_height, pad, 0);

-

-    if (!ximage) {

-        fprintf(stderr, PROGNAME ":  XCreateImage() failed\n");

-        free(xdata);

-        return 3;

-    }

-

-    /* to avoid testing the byte order every pixel (or doubling the size of

-     * the drawing routine with a giant if-test), we arbitrarily set the byte

-     * order to MSBFirst and let Xlib worry about inverting things on little-

-     * endian machines (like Linux/x86, old VAXen, etc.)--this is not the most

-     * efficient approach (the giant if-test would be better), but in the

-     * interest of clarity, we take the easy way out... */

-

-    ximage->byte_order = MSBFirst;

-

-    return 0;

-

-} /* end function rpng_x_create_window() */

-

-

-

-

-

-static int rpng_x_display_image(void)

-{

-    uch *src;

-    char *dest;

-    uch r, g, b, a;

-    ulg i, row, lastrow = 0;

-    ulg pixel;

-    int ximage_rowbytes = ximage->bytes_per_line;

-/*  int bpp = ximage->bits_per_pixel;  */

-

-

-    Trace((stderr, "beginning display loop (image_channels == %d)\n",

-      image_channels))

-    Trace((stderr, "   (width = %ld, rowbytes = %ld, ximage_rowbytes = %d)\n",

-      image_width, image_rowbytes, ximage_rowbytes))

-    Trace((stderr, "   (bpp = %d)\n", ximage->bits_per_pixel))

-    Trace((stderr, "   (byte_order = %s)\n", ximage->byte_order == MSBFirst?

-      "MSBFirst" : (ximage->byte_order == LSBFirst? "LSBFirst" : "unknown")))

-

-    if (depth == 24 || depth == 32) {

-        ulg red, green, blue;

-

-        for (lastrow = row = 0;  row < image_height;  ++row) {

-            src = image_data + row*image_rowbytes;

-            dest = ximage->data + row*ximage_rowbytes;

-            if (image_channels == 3) {

-                for (i = image_width;  i > 0;  --i) {

-                    red   = *src++;

-                    green = *src++;

-                    blue  = *src++;

-#ifdef NO_24BIT_MASKS

-                    pixel = (red   << RShift) |

-                            (green << GShift) |

-                            (blue  << BShift);

-                    /* recall that we set ximage->byte_order = MSBFirst above */

-                    /* GRR BUG:  this assumes bpp == 32, but may be 24: */

-                    *dest++ = (char)((pixel >> 24) & 0xff);

-                    *dest++ = (char)((pixel >> 16) & 0xff);

-                    *dest++ = (char)((pixel >>  8) & 0xff);

-                    *dest++ = (char)( pixel        & 0xff);

-#else

-                    red   = (RShift < 0)? red   << (-RShift) : red   >> RShift;

-                    green = (GShift < 0)? green << (-GShift) : green >> GShift;

-                    blue  = (BShift < 0)? blue  << (-BShift) : blue  >> BShift;

-                    pixel = (red & RMask) | (green & GMask) | (blue & BMask);

-                    /* recall that we set ximage->byte_order = MSBFirst above */

-                    *dest++ = (char)((pixel >> 24) & 0xff);

-                    *dest++ = (char)((pixel >> 16) & 0xff);

-                    *dest++ = (char)((pixel >>  8) & 0xff);

-                    *dest++ = (char)( pixel        & 0xff);

-#endif

-                }

-            } else /* if (image_channels == 4) */ {

-                for (i = image_width;  i > 0;  --i) {

-                    r = *src++;

-                    g = *src++;

-                    b = *src++;

-                    a = *src++;

-                    if (a == 255) {

-                        red   = r;

-                        green = g;

-                        blue  = b;

-                    } else if (a == 0) {

-                        red   = bg_red;

-                        green = bg_green;

-                        blue  = bg_blue;

-                    } else {

-                        /* this macro (from png.h) composites the foreground

-                         * and background values and puts the result into the

-                         * first argument */

-                        alpha_composite(red,   r, a, bg_red);

-                        alpha_composite(green, g, a, bg_green);

-                        alpha_composite(blue,  b, a, bg_blue);

-                    }

-                    pixel = (red   << RShift) |

-                            (green << GShift) |

-                            (blue  << BShift);

-                    /* recall that we set ximage->byte_order = MSBFirst above */

-                    *dest++ = (char)((pixel >> 24) & 0xff);

-                    *dest++ = (char)((pixel >> 16) & 0xff);

-                    *dest++ = (char)((pixel >>  8) & 0xff);

-                    *dest++ = (char)( pixel        & 0xff);

-                }

-            }

-            /* display after every 16 lines */

-            if (((row+1) & 0xf) == 0) {

-                XPutImage(display, window, gc, ximage, 0, (int)lastrow, 0,

-                  (int)lastrow, image_width, 16);

-                XFlush(display);

-                lastrow = row + 1;

-            }

-        }

-

-    } else if (depth == 16) {

-        ush red, green, blue;

-

-        for (lastrow = row = 0;  row < image_height;  ++row) {

-            src = image_data + row*image_rowbytes;

-            dest = ximage->data + row*ximage_rowbytes;

-            if (image_channels == 3) {

-                for (i = image_width;  i > 0;  --i) {

-                    red   = ((ush)(*src) << 8);

-                    ++src;

-                    green = ((ush)(*src) << 8);

-                    ++src;

-                    blue  = ((ush)(*src) << 8);

-                    ++src;

-                    pixel = ((red   >> RShift) & RMask) |

-                            ((green >> GShift) & GMask) |

-                            ((blue  >> BShift) & BMask);

-                    /* recall that we set ximage->byte_order = MSBFirst above */

-                    *dest++ = (char)((pixel >>  8) & 0xff);

-                    *dest++ = (char)( pixel        & 0xff);

-                }

-            } else /* if (image_channels == 4) */ {

-                for (i = image_width;  i > 0;  --i) {

-                    r = *src++;

-                    g = *src++;

-                    b = *src++;

-                    a = *src++;

-                    if (a == 255) {

-                        red   = ((ush)r << 8);

-                        green = ((ush)g << 8);

-                        blue  = ((ush)b << 8);

-                    } else if (a == 0) {

-                        red   = ((ush)bg_red   << 8);

-                        green = ((ush)bg_green << 8);

-                        blue  = ((ush)bg_blue  << 8);

-                    } else {

-                        /* this macro (from png.h) composites the foreground

-                         * and background values and puts the result back into

-                         * the first argument (== fg byte here:  safe) */

-                        alpha_composite(r, r, a, bg_red);

-                        alpha_composite(g, g, a, bg_green);

-                        alpha_composite(b, b, a, bg_blue);

-                        red   = ((ush)r << 8);

-                        green = ((ush)g << 8);

-                        blue  = ((ush)b << 8);

-                    }

-                    pixel = ((red   >> RShift) & RMask) |

-                            ((green >> GShift) & GMask) |

-                            ((blue  >> BShift) & BMask);

-                    /* recall that we set ximage->byte_order = MSBFirst above */

-                    *dest++ = (char)((pixel >>  8) & 0xff);

-                    *dest++ = (char)( pixel        & 0xff);

-                }

-            }

-            /* display after every 16 lines */

-            if (((row+1) & 0xf) == 0) {

-                XPutImage(display, window, gc, ximage, 0, (int)lastrow, 0,

-                  (int)lastrow, image_width, 16);

-                XFlush(display);

-                lastrow = row + 1;

-            }

-        }

-

-    } else /* depth == 8 */ {

-

-        /* GRR:  add 8-bit support */

-

-    }

-

-    Trace((stderr, "calling final XPutImage()\n"))

-    if (lastrow < image_height) {

-        XPutImage(display, window, gc, ximage, 0, (int)lastrow, 0,

-          (int)lastrow, image_width, image_height-lastrow);

-        XFlush(display);

-    }

-

-    return 0;

-}

-

-

-

-

-static void rpng_x_cleanup(void)

-{

-    if (image_data) {

-        free(image_data);

-        image_data = NULL;

-    }

-

-    if (ximage) {

-        if (ximage->data) {

-            free(ximage->data);           /* we allocated it, so we free it */

-            ximage->data = (char *)NULL;  /*  instead of XDestroyImage() */

-        }

-        XDestroyImage(ximage);

-        ximage = NULL;

-    }

-

-    if (have_gc)

-        XFreeGC(display, gc);

-

-    if (have_window)

-        XDestroyWindow(display, window);

-

-    if (have_colormap)

-        XFreeColormap(display, colormap);

-

-    if (have_nondefault_visual)

-        XFree(visual_list);

-}

-

-

-

-

-

-static int rpng_x_msb(ulg u32val)

-{

-    int i;

-

-    for (i = 31;  i >= 0;  --i) {

-        if (u32val & 0x80000000L)

-            break;

-        u32val <<= 1;

-    }

-    return i;

-}

+/*---------------------------------------------------------------------------
+
+   rpng - simple PNG display program                               rpng-x.c
+
+   This program decodes and displays PNG images, with gamma correction and
+   optionally with a user-specified background color (in case the image has
+   transparency).  It is very nearly the most basic PNG viewer possible.
+   This version is for the X Window System (tested by author under Unix and
+   by Martin Zinser under OpenVMS; may work under OS/2 with some tweaking).
+
+   to do:
+    - 8-bit (colormapped) X support
+    - use %.1023s to simplify truncation of title-bar string?
+
+  ---------------------------------------------------------------------------
+
+   Changelog:
+    - 1.01:  initial public release
+    - 1.02:  modified to allow abbreviated options; fixed long/ulong mis-
+              match; switched to png_jmpbuf() macro
+    - 1.10:  added support for non-default visuals; fixed X pixel-conversion
+    - 1.11:  added extra set of parentheses to png_jmpbuf() macro; fixed
+              command-line parsing bug
+    - 1.12:  fixed some small X memory leaks (thanks to François Petitjean)
+    - 1.13:  fixed XFreeGC() crash bug (thanks to Patrick Welche)
+    - 1.14:  added support for X resources (thanks to Gerhard Niklasch)
+    - 2.00:  dual-licensed (added GNU GPL)
+    - 2.01:  fixed improper display of usage screen on PNG error(s)
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-2008 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      The contents of this file are DUAL-LICENSED.  You may modify and/or
+      redistribute this software according to the terms of one of the
+      following two licenses (at your option):
+
+
+      LICENSE 1 ("BSD-like with advertising clause"):
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+
+      LICENSE 2 (GNU GPL v2 or later):
+
+      This program is free software; you can redistribute it and/or modify
+      it under the terms of the GNU General Public License as published by
+      the Free Software Foundation; either version 2 of the License, or
+      (at your option) any later version.
+
+      This program is distributed in the hope that it will be useful,
+      but WITHOUT ANY WARRANTY; without even the implied warranty of
+      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+      GNU General Public License for more details.
+
+      You should have received a copy of the GNU General Public License
+      along with this program; if not, write to the Free Software Foundation,
+      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+  ---------------------------------------------------------------------------*/
+
+#define PROGNAME  "rpng-x"
+#define LONGNAME  "Simple PNG Viewer for X"
+#define VERSION   "2.01 of 16 March 2008"
+#define RESNAME   "rpng"        /* our X resource application name */
+#define RESCLASS  "Rpng"        /* our X resource class name */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <X11/Xlib.h>
+#include <X11/Xutil.h>
+#include <X11/Xos.h>
+#include <X11/keysym.h>
+
+/* #define DEBUG  :  this enables the Trace() macros */
+
+#include "readpng.h"   /* typedefs, common macros, readpng prototypes */
+
+
+/* could just include png.h, but this macro is the only thing we need
+ * (name and typedefs changed to local versions); note that side effects
+ * only happen with alpha (which could easily be avoided with
+ * "ush acopy = (alpha);") */
+
+#define alpha_composite(composite, fg, alpha, bg) {               \
+    ush temp = ((ush)(fg)*(ush)(alpha) +                          \
+                (ush)(bg)*(ush)(255 - (ush)(alpha)) + (ush)128);  \
+    (composite) = (uch)((temp + (temp >> 8)) >> 8);               \
+}
+
+
+/* local prototypes */
+static int  rpng_x_create_window(void);
+static int  rpng_x_display_image(void);
+static void rpng_x_cleanup(void);
+static int  rpng_x_msb(ulg u32val);
+
+
+static char titlebar[1024], *window_name = titlebar;
+static char *appname = LONGNAME;
+static char *icon_name = PROGNAME;
+static char *res_name = RESNAME;
+static char *res_class = RESCLASS;
+static char *filename;
+static FILE *infile;
+
+static char *bgstr;
+static uch bg_red=0, bg_green=0, bg_blue=0;
+
+static double display_exponent;
+
+static ulg image_width, image_height, image_rowbytes;
+static int image_channels;
+static uch *image_data;
+
+/* X-specific variables */
+static char *displayname;
+static XImage *ximage;
+static Display *display;
+static int depth;
+static Visual *visual;
+static XVisualInfo *visual_list;
+static int RShift, GShift, BShift;
+static ulg RMask, GMask, BMask;
+static Window window;
+static GC gc;
+static Colormap colormap;
+
+static int have_nondefault_visual = FALSE;
+static int have_colormap = FALSE;
+static int have_window = FALSE;
+static int have_gc = FALSE;
+/*
+ulg numcolors=0, pixels[256];
+ush reds[256], greens[256], blues[256];
+ */
+
+
+
+
+int main(int argc, char **argv)
+{
+#ifdef sgi
+    char tmpline[80];
+#endif
+    char *p;
+    int rc, alen, flen;
+    int error = 0;
+    int have_bg = FALSE;
+    double LUT_exponent;               /* just the lookup table */
+    double CRT_exponent = 2.2;         /* just the monitor */
+    double default_display_exponent;   /* whole display system */
+    XEvent e;
+    KeySym k;
+
+
+    displayname = (char *)NULL;
+    filename = (char *)NULL;
+
+
+    /* First set the default value for our display-system exponent, i.e.,
+     * the product of the CRT exponent and the exponent corresponding to
+     * the frame-buffer's lookup table (LUT), if any.  This is not an
+     * exhaustive list of LUT values (e.g., OpenStep has a lot of weird
+     * ones), but it should cover 99% of the current possibilities. */
+
+#if defined(NeXT)
+    LUT_exponent = 1.0 / 2.2;
+    /*
+    if (some_next_function_that_returns_gamma(&next_gamma))
+        LUT_exponent = 1.0 / next_gamma;
+     */
+#elif defined(sgi)
+    LUT_exponent = 1.0 / 1.7;
+    /* there doesn't seem to be any documented function to get the
+     * "gamma" value, so we do it the hard way */
+    infile = fopen("/etc/config/system.glGammaVal", "r");
+    if (infile) {
+        double sgi_gamma;
+
+        fgets(tmpline, 80, infile);
+        fclose(infile);
+        sgi_gamma = atof(tmpline);
+        if (sgi_gamma > 0.0)
+            LUT_exponent = 1.0 / sgi_gamma;
+    }
+#elif defined(Macintosh)
+    LUT_exponent = 1.8 / 2.61;
+    /*
+    if (some_mac_function_that_returns_gamma(&mac_gamma))
+        LUT_exponent = mac_gamma / 2.61;
+     */
+#else
+    LUT_exponent = 1.0;   /* assume no LUT:  most PCs */
+#endif
+
+    /* the defaults above give 1.0, 1.3, 1.5 and 2.2, respectively: */
+    default_display_exponent = LUT_exponent * CRT_exponent;
+
+
+    /* If the user has set the SCREEN_GAMMA environment variable as suggested
+     * (somewhat imprecisely) in the libpng documentation, use that; otherwise
+     * use the default value we just calculated.  Either way, the user may
+     * override this via a command-line option. */
+
+    if ((p = getenv("SCREEN_GAMMA")) != NULL)
+        display_exponent = atof(p);
+    else
+        display_exponent = default_display_exponent;
+
+
+    /* Now parse the command line for options and the PNG filename. */
+
+    while (*++argv && !error) {
+        if (!strncmp(*argv, "-display", 2)) {
+            if (!*++argv)
+                ++error;
+            else
+                displayname = *argv;
+        } else if (!strncmp(*argv, "-gamma", 2)) {
+            if (!*++argv)
+                ++error;
+            else {
+                display_exponent = atof(*argv);
+                if (display_exponent <= 0.0)
+                    ++error;
+            }
+        } else if (!strncmp(*argv, "-bgcolor", 2)) {
+            if (!*++argv)
+                ++error;
+            else {
+                bgstr = *argv;
+                if (strlen(bgstr) != 7 || bgstr[0] != '#')
+                    ++error;
+                else
+                    have_bg = TRUE;
+            }
+        } else {
+            if (**argv != '-') {
+                filename = *argv;
+                if (argv[1])   /* shouldn't be any more args after filename */
+                    ++error;
+            } else
+                ++error;   /* not expecting any other options */
+        }
+    }
+
+    if (!filename)
+        ++error;
+
+
+    /* print usage screen if any errors up to this point */
+
+    if (error) {
+        fprintf(stderr, "\n%s %s:  %s\n", PROGNAME, VERSION, appname);
+        readpng_version_info();
+        fprintf(stderr, "\n"
+          "Usage:  %s [-display xdpy] [-gamma exp] [-bgcolor bg] file.png\n"
+          "    xdpy\tname of the target X display (e.g., ``hostname:0'')\n"
+          "    exp \ttransfer-function exponent (``gamma'') of the display\n"
+          "\t\t  system in floating-point format (e.g., ``%.1f''); equal\n"
+          "\t\t  to the product of the lookup-table exponent (varies)\n"
+          "\t\t  and the CRT exponent (usually 2.2); must be positive\n"
+          "    bg  \tdesired background color in 7-character hex RGB format\n"
+          "\t\t  (e.g., ``#ff7700'' for orange:  same as HTML colors);\n"
+          "\t\t  used with transparent images\n"
+          "\nPress Q, Esc or mouse button 1 (within image window, after image\n"
+          "is displayed) to quit.\n"
+          "\n", PROGNAME, default_display_exponent);
+        exit(1);
+    }
+
+
+    if (!(infile = fopen(filename, "rb"))) {
+        fprintf(stderr, PROGNAME ":  can't open PNG file [%s]\n", filename);
+        ++error;
+    } else {
+        if ((rc = readpng_init(infile, &image_width, &image_height)) != 0) {
+            switch (rc) {
+                case 1:
+                    fprintf(stderr, PROGNAME
+                      ":  [%s] is not a PNG file: incorrect signature\n",
+                      filename);
+                    break;
+                case 2:
+                    fprintf(stderr, PROGNAME
+                      ":  [%s] has bad IHDR (libpng longjmp)\n", filename);
+                    break;
+                case 4:
+                    fprintf(stderr, PROGNAME ":  insufficient memory\n");
+                    break;
+                default:
+                    fprintf(stderr, PROGNAME
+                      ":  unknown readpng_init() error\n");
+                    break;
+            }
+            ++error;
+        } else {
+            display = XOpenDisplay(displayname);
+            if (!display) {
+                readpng_cleanup(TRUE);
+                fprintf(stderr, PROGNAME ":  can't open X display [%s]\n",
+                  displayname? displayname : "default");
+                ++error;
+            }
+        }
+        if (error)
+            fclose(infile);
+    }
+
+
+    if (error) {
+        fprintf(stderr, PROGNAME ":  aborting.\n");
+        exit(2);
+    }
+
+
+    /* set the title-bar string, but make sure buffer doesn't overflow */
+
+    alen = strlen(appname);
+    flen = strlen(filename);
+    if (alen + flen + 3 > 1023)
+        sprintf(titlebar, "%s:  ...%s", appname, filename+(alen+flen+6-1023));
+    else
+        sprintf(titlebar, "%s:  %s", appname, filename);
+
+
+    /* if the user didn't specify a background color on the command line,
+     * check for one in the PNG file--if not, the initialized values of 0
+     * (black) will be used */
+
+    if (have_bg) {
+        unsigned r, g, b;   /* this approach quiets compiler warnings */
+
+        sscanf(bgstr+1, "%2x%2x%2x", &r, &g, &b);
+        bg_red   = (uch)r;
+        bg_green = (uch)g;
+        bg_blue  = (uch)b;
+    } else if (readpng_get_bgcolor(&bg_red, &bg_green, &bg_blue) > 1) {
+        readpng_cleanup(TRUE);
+        fprintf(stderr, PROGNAME
+          ":  libpng error while checking for background color\n");
+        exit(2);
+    }
+
+
+    /* do the basic X initialization stuff, make the window and fill it
+     * with the background color */
+
+    if (rpng_x_create_window())
+        exit(2);
+
+
+    /* decode the image, all at once */
+
+    Trace((stderr, "calling readpng_get_image()\n"))
+    image_data = readpng_get_image(display_exponent, &image_channels,
+      &image_rowbytes);
+    Trace((stderr, "done with readpng_get_image()\n"))
+
+
+    /* done with PNG file, so clean up to minimize memory usage (but do NOT
+     * nuke image_data!) */
+
+    readpng_cleanup(FALSE);
+    fclose(infile);
+
+    if (!image_data) {
+        fprintf(stderr, PROGNAME ":  unable to decode PNG image\n");
+        exit(3);
+    }
+
+
+    /* display image (composite with background if requested) */
+
+    Trace((stderr, "calling rpng_x_display_image()\n"))
+    if (rpng_x_display_image()) {
+        free(image_data);
+        exit(4);
+    }
+    Trace((stderr, "done with rpng_x_display_image()\n"))
+
+
+    /* wait for the user to tell us when to quit */
+
+    printf(
+      "Done.  Press Q, Esc or mouse button 1 (within image window) to quit.\n");
+    fflush(stdout);
+
+    do
+        XNextEvent(display, &e);
+    while (!(e.type == ButtonPress && e.xbutton.button == Button1) &&
+           !(e.type == KeyPress &&    /*  v--- or 1 for shifted keys */
+             ((k = XLookupKeysym(&e.xkey, 0)) == XK_q || k == XK_Escape) ));
+
+
+    /* OK, we're done:  clean up all image and X resources and go away */
+
+    rpng_x_cleanup();
+
+    return 0;
+}
+
+
+
+
+
+static int rpng_x_create_window(void)
+{
+    uch *xdata;
+    int need_colormap = FALSE;
+    int screen, pad;
+    ulg bg_pixel = 0L;
+    ulg attrmask;
+    Window root;
+    XEvent e;
+    XGCValues gcvalues;
+    XSetWindowAttributes attr;
+    XTextProperty windowName, *pWindowName = &windowName;
+    XTextProperty iconName, *pIconName = &iconName;
+    XVisualInfo visual_info;
+    XSizeHints *size_hints;
+    XWMHints *wm_hints;
+    XClassHint *class_hints;
+
+
+    screen = DefaultScreen(display);
+    depth = DisplayPlanes(display, screen);
+    root = RootWindow(display, screen);
+
+#ifdef DEBUG
+    XSynchronize(display, True);
+#endif
+
+#if 0
+/* GRR:  add 8-bit support */
+    if (/* depth != 8 && */ depth != 16 && depth != 24 && depth != 32) {
+        fprintf(stderr,
+          "screen depth %d not supported (only 16-, 24- or 32-bit TrueColor)\n",
+          depth);
+        return 2;
+    }
+
+    XMatchVisualInfo(display, screen, depth,
+      (depth == 8)? PseudoColor : TrueColor, &visual_info);
+    visual = visual_info.visual;
+#else
+    if (depth != 16 && depth != 24 && depth != 32) {
+        int visuals_matched = 0;
+
+        Trace((stderr, "default depth is %d:  checking other visuals\n",
+          depth))
+
+        /* 24-bit first */
+        visual_info.screen = screen;
+        visual_info.depth = 24;
+        visual_list = XGetVisualInfo(display,
+          VisualScreenMask | VisualDepthMask, &visual_info, &visuals_matched);
+        if (visuals_matched == 0) {
+/* GRR:  add 15-, 16- and 32-bit TrueColor visuals (also DirectColor?) */
+            fprintf(stderr, "default screen depth %d not supported, and no"
+              " 24-bit visuals found\n", depth);
+            return 2;
+        }
+        Trace((stderr, "XGetVisualInfo() returned %d 24-bit visuals\n",
+          visuals_matched))
+        visual = visual_list[0].visual;
+        depth = visual_list[0].depth;
+/*
+        colormap_size = visual_list[0].colormap_size;
+        visual_class = visual->class;
+        visualID = XVisualIDFromVisual(visual);
+ */
+        have_nondefault_visual = TRUE;
+        need_colormap = TRUE;
+    } else {
+        XMatchVisualInfo(display, screen, depth, TrueColor, &visual_info);
+        visual = visual_info.visual;
+    }
+#endif
+
+    RMask = visual->red_mask;
+    GMask = visual->green_mask;
+    BMask = visual->blue_mask;
+
+/* GRR:  add/check 8-bit support */
+    if (depth == 8 || need_colormap) {
+        colormap = XCreateColormap(display, root, visual, AllocNone);
+        if (!colormap) {
+            fprintf(stderr, "XCreateColormap() failed\n");
+            return 2;
+        }
+        have_colormap = TRUE;
+    }
+    if (depth == 15 || depth == 16) {
+        RShift = 15 - rpng_x_msb(RMask);    /* these are right-shifts */
+        GShift = 15 - rpng_x_msb(GMask);
+        BShift = 15 - rpng_x_msb(BMask);
+    } else if (depth > 16) {
+#define NO_24BIT_MASKS
+#ifdef NO_24BIT_MASKS
+        RShift = rpng_x_msb(RMask) - 7;     /* these are left-shifts */
+        GShift = rpng_x_msb(GMask) - 7;
+        BShift = rpng_x_msb(BMask) - 7;
+#else
+        RShift = 7 - rpng_x_msb(RMask);     /* these are right-shifts, too */
+        GShift = 7 - rpng_x_msb(GMask);
+        BShift = 7 - rpng_x_msb(BMask);
+#endif
+    }
+    if (depth >= 15 && (RShift < 0 || GShift < 0 || BShift < 0)) {
+        fprintf(stderr, "rpng internal logic error:  negative X shift(s)!\n");
+        return 2;
+    }
+
+/*---------------------------------------------------------------------------
+    Finally, create the window.
+  ---------------------------------------------------------------------------*/
+
+    attr.backing_store = Always;
+    attr.event_mask = ExposureMask | KeyPressMask | ButtonPressMask;
+    attrmask = CWBackingStore | CWEventMask;
+    if (have_nondefault_visual) {
+        attr.colormap = colormap;
+        attr.background_pixel = 0;
+        attr.border_pixel = 1;
+        attrmask |= CWColormap | CWBackPixel | CWBorderPixel;
+    }
+
+    window = XCreateWindow(display, root, 0, 0, image_width, image_height, 0,
+      depth, InputOutput, visual, attrmask, &attr);
+
+    if (window == None) {
+        fprintf(stderr, "XCreateWindow() failed\n");
+        return 2;
+    } else
+        have_window = TRUE;
+
+    if (depth == 8)
+        XSetWindowColormap(display, window, colormap);
+
+    if (!XStringListToTextProperty(&window_name, 1, pWindowName))
+        pWindowName = NULL;
+    if (!XStringListToTextProperty(&icon_name, 1, pIconName))
+        pIconName = NULL;
+
+    /* OK if any hints allocation fails; XSetWMProperties() allows NULLs */
+
+    if ((size_hints = XAllocSizeHints()) != NULL) {
+        /* window will not be resizable */
+        size_hints->flags = PMinSize | PMaxSize;
+        size_hints->min_width = size_hints->max_width = (int)image_width;
+        size_hints->min_height = size_hints->max_height = (int)image_height;
+    }
+
+    if ((wm_hints = XAllocWMHints()) != NULL) {
+        wm_hints->initial_state = NormalState;
+        wm_hints->input = True;
+     /* wm_hints->icon_pixmap = icon_pixmap; */
+        wm_hints->flags = StateHint | InputHint  /* | IconPixmapHint */ ;
+    }
+
+    if ((class_hints = XAllocClassHint()) != NULL) {
+        class_hints->res_name = res_name;
+        class_hints->res_class = res_class;
+    }
+
+    XSetWMProperties(display, window, pWindowName, pIconName, NULL, 0,
+      size_hints, wm_hints, class_hints);
+
+    /* various properties and hints no longer needed; free memory */
+    if (pWindowName)
+       XFree(pWindowName->value);
+    if (pIconName)
+       XFree(pIconName->value);
+    if (size_hints)
+        XFree(size_hints);
+    if (wm_hints)
+       XFree(wm_hints);
+    if (class_hints)
+       XFree(class_hints);
+
+    XMapWindow(display, window);
+
+    gc = XCreateGC(display, window, 0, &gcvalues);
+    have_gc = TRUE;
+
+/*---------------------------------------------------------------------------
+    Fill window with the specified background color.
+  ---------------------------------------------------------------------------*/
+
+    if (depth == 24 || depth == 32) {
+        bg_pixel = ((ulg)bg_red   << RShift) |
+                   ((ulg)bg_green << GShift) |
+                   ((ulg)bg_blue  << BShift);
+    } else if (depth == 16) {
+        bg_pixel = ((((ulg)bg_red   << 8) >> RShift) & RMask) |
+                   ((((ulg)bg_green << 8) >> GShift) & GMask) |
+                   ((((ulg)bg_blue  << 8) >> BShift) & BMask);
+    } else /* depth == 8 */ {
+
+        /* GRR:  add 8-bit support */
+
+    }
+
+    XSetForeground(display, gc, bg_pixel);
+    XFillRectangle(display, window, gc, 0, 0, image_width, image_height);
+
+/*---------------------------------------------------------------------------
+    Wait for first Expose event to do any drawing, then flush.
+  ---------------------------------------------------------------------------*/
+
+    do
+        XNextEvent(display, &e);
+    while (e.type != Expose || e.xexpose.count);
+
+    XFlush(display);
+
+/*---------------------------------------------------------------------------
+    Allocate memory for the X- and display-specific version of the image.
+  ---------------------------------------------------------------------------*/
+
+    if (depth == 24 || depth == 32) {
+        xdata = (uch *)malloc(4*image_width*image_height);
+        pad = 32;
+    } else if (depth == 16) {
+        xdata = (uch *)malloc(2*image_width*image_height);
+        pad = 16;
+    } else /* depth == 8 */ {
+        xdata = (uch *)malloc(image_width*image_height);
+        pad = 8;
+    }
+
+    if (!xdata) {
+        fprintf(stderr, PROGNAME ":  unable to allocate image memory\n");
+        return 4;
+    }
+
+    ximage = XCreateImage(display, visual, depth, ZPixmap, 0,
+      (char *)xdata, image_width, image_height, pad, 0);
+
+    if (!ximage) {
+        fprintf(stderr, PROGNAME ":  XCreateImage() failed\n");
+        free(xdata);
+        return 3;
+    }
+
+    /* to avoid testing the byte order every pixel (or doubling the size of
+     * the drawing routine with a giant if-test), we arbitrarily set the byte
+     * order to MSBFirst and let Xlib worry about inverting things on little-
+     * endian machines (like Linux/x86, old VAXen, etc.)--this is not the most
+     * efficient approach (the giant if-test would be better), but in the
+     * interest of clarity, we take the easy way out... */
+
+    ximage->byte_order = MSBFirst;
+
+    return 0;
+
+} /* end function rpng_x_create_window() */
+
+
+
+
+
+static int rpng_x_display_image(void)
+{
+    uch *src;
+    char *dest;
+    uch r, g, b, a;
+    ulg i, row, lastrow = 0;
+    ulg pixel;
+    int ximage_rowbytes = ximage->bytes_per_line;
+/*  int bpp = ximage->bits_per_pixel;  */
+
+
+    Trace((stderr, "beginning display loop (image_channels == %d)\n",
+      image_channels))
+    Trace((stderr, "   (width = %ld, rowbytes = %ld, ximage_rowbytes = %d)\n",
+      image_width, image_rowbytes, ximage_rowbytes))
+    Trace((stderr, "   (bpp = %d)\n", ximage->bits_per_pixel))
+    Trace((stderr, "   (byte_order = %s)\n", ximage->byte_order == MSBFirst?
+      "MSBFirst" : (ximage->byte_order == LSBFirst? "LSBFirst" : "unknown")))
+
+    if (depth == 24 || depth == 32) {
+        ulg red, green, blue;
+
+        for (lastrow = row = 0;  row < image_height;  ++row) {
+            src = image_data + row*image_rowbytes;
+            dest = ximage->data + row*ximage_rowbytes;
+            if (image_channels == 3) {
+                for (i = image_width;  i > 0;  --i) {
+                    red   = *src++;
+                    green = *src++;
+                    blue  = *src++;
+#ifdef NO_24BIT_MASKS
+                    pixel = (red   << RShift) |
+                            (green << GShift) |
+                            (blue  << BShift);
+                    /* recall that we set ximage->byte_order = MSBFirst above */
+                    /* GRR BUG:  this assumes bpp == 32, but may be 24: */
+                    *dest++ = (char)((pixel >> 24) & 0xff);
+                    *dest++ = (char)((pixel >> 16) & 0xff);
+                    *dest++ = (char)((pixel >>  8) & 0xff);
+                    *dest++ = (char)( pixel        & 0xff);
+#else
+                    red   = (RShift < 0)? red   << (-RShift) : red   >> RShift;
+                    green = (GShift < 0)? green << (-GShift) : green >> GShift;
+                    blue  = (BShift < 0)? blue  << (-BShift) : blue  >> BShift;
+                    pixel = (red & RMask) | (green & GMask) | (blue & BMask);
+                    /* recall that we set ximage->byte_order = MSBFirst above */
+                    *dest++ = (char)((pixel >> 24) & 0xff);
+                    *dest++ = (char)((pixel >> 16) & 0xff);
+                    *dest++ = (char)((pixel >>  8) & 0xff);
+                    *dest++ = (char)( pixel        & 0xff);
+#endif
+                }
+            } else /* if (image_channels == 4) */ {
+                for (i = image_width;  i > 0;  --i) {
+                    r = *src++;
+                    g = *src++;
+                    b = *src++;
+                    a = *src++;
+                    if (a == 255) {
+                        red   = r;
+                        green = g;
+                        blue  = b;
+                    } else if (a == 0) {
+                        red   = bg_red;
+                        green = bg_green;
+                        blue  = bg_blue;
+                    } else {
+                        /* this macro (from png.h) composites the foreground
+                         * and background values and puts the result into the
+                         * first argument */
+                        alpha_composite(red,   r, a, bg_red);
+                        alpha_composite(green, g, a, bg_green);
+                        alpha_composite(blue,  b, a, bg_blue);
+                    }
+                    pixel = (red   << RShift) |
+                            (green << GShift) |
+                            (blue  << BShift);
+                    /* recall that we set ximage->byte_order = MSBFirst above */
+                    *dest++ = (char)((pixel >> 24) & 0xff);
+                    *dest++ = (char)((pixel >> 16) & 0xff);
+                    *dest++ = (char)((pixel >>  8) & 0xff);
+                    *dest++ = (char)( pixel        & 0xff);
+                }
+            }
+            /* display after every 16 lines */
+            if (((row+1) & 0xf) == 0) {
+                XPutImage(display, window, gc, ximage, 0, (int)lastrow, 0,
+                  (int)lastrow, image_width, 16);
+                XFlush(display);
+                lastrow = row + 1;
+            }
+        }
+
+    } else if (depth == 16) {
+        ush red, green, blue;
+
+        for (lastrow = row = 0;  row < image_height;  ++row) {
+            src = image_data + row*image_rowbytes;
+            dest = ximage->data + row*ximage_rowbytes;
+            if (image_channels == 3) {
+                for (i = image_width;  i > 0;  --i) {
+                    red   = ((ush)(*src) << 8);
+                    ++src;
+                    green = ((ush)(*src) << 8);
+                    ++src;
+                    blue  = ((ush)(*src) << 8);
+                    ++src;
+                    pixel = ((red   >> RShift) & RMask) |
+                            ((green >> GShift) & GMask) |
+                            ((blue  >> BShift) & BMask);
+                    /* recall that we set ximage->byte_order = MSBFirst above */
+                    *dest++ = (char)((pixel >>  8) & 0xff);
+                    *dest++ = (char)( pixel        & 0xff);
+                }
+            } else /* if (image_channels == 4) */ {
+                for (i = image_width;  i > 0;  --i) {
+                    r = *src++;
+                    g = *src++;
+                    b = *src++;
+                    a = *src++;
+                    if (a == 255) {
+                        red   = ((ush)r << 8);
+                        green = ((ush)g << 8);
+                        blue  = ((ush)b << 8);
+                    } else if (a == 0) {
+                        red   = ((ush)bg_red   << 8);
+                        green = ((ush)bg_green << 8);
+                        blue  = ((ush)bg_blue  << 8);
+                    } else {
+                        /* this macro (from png.h) composites the foreground
+                         * and background values and puts the result back into
+                         * the first argument (== fg byte here:  safe) */
+                        alpha_composite(r, r, a, bg_red);
+                        alpha_composite(g, g, a, bg_green);
+                        alpha_composite(b, b, a, bg_blue);
+                        red   = ((ush)r << 8);
+                        green = ((ush)g << 8);
+                        blue  = ((ush)b << 8);
+                    }
+                    pixel = ((red   >> RShift) & RMask) |
+                            ((green >> GShift) & GMask) |
+                            ((blue  >> BShift) & BMask);
+                    /* recall that we set ximage->byte_order = MSBFirst above */
+                    *dest++ = (char)((pixel >>  8) & 0xff);
+                    *dest++ = (char)( pixel        & 0xff);
+                }
+            }
+            /* display after every 16 lines */
+            if (((row+1) & 0xf) == 0) {
+                XPutImage(display, window, gc, ximage, 0, (int)lastrow, 0,
+                  (int)lastrow, image_width, 16);
+                XFlush(display);
+                lastrow = row + 1;
+            }
+        }
+
+    } else /* depth == 8 */ {
+
+        /* GRR:  add 8-bit support */
+
+    }
+
+    Trace((stderr, "calling final XPutImage()\n"))
+    if (lastrow < image_height) {
+        XPutImage(display, window, gc, ximage, 0, (int)lastrow, 0,
+          (int)lastrow, image_width, image_height-lastrow);
+        XFlush(display);
+    }
+
+    return 0;
+}
+
+
+
+
+static void rpng_x_cleanup(void)
+{
+    if (image_data) {
+        free(image_data);
+        image_data = NULL;
+    }
+
+    if (ximage) {
+        if (ximage->data) {
+            free(ximage->data);           /* we allocated it, so we free it */
+            ximage->data = (char *)NULL;  /*  instead of XDestroyImage() */
+        }
+        XDestroyImage(ximage);
+        ximage = NULL;
+    }
+
+    if (have_gc)
+        XFreeGC(display, gc);
+
+    if (have_window)
+        XDestroyWindow(display, window);
+
+    if (have_colormap)
+        XFreeColormap(display, colormap);
+
+    if (have_nondefault_visual)
+        XFree(visual_list);
+}
+
+
+
+
+
+static int rpng_x_msb(ulg u32val)
+{
+    int i;
+
+    for (i = 31;  i >= 0;  --i) {
+        if (u32val & 0x80000000L)
+            break;
+        u32val <<= 1;
+    }
+    return i;
+}
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/rpng2-win.c b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/rpng2-win.c
index 2303b58..223e737 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/rpng2-win.c
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/rpng2-win.c
@@ -1,1253 +1,1253 @@
-/*---------------------------------------------------------------------------

-

-   rpng2 - progressive-model PNG display program                rpng2-win.c

-

-   This program decodes and displays PNG files progressively, as if it were

-   a web browser (though the front end is only set up to read from files).

-   It supports gamma correction, user-specified background colors, and user-

-   specified background patterns (for transparent images).  This version is

-   for 32-bit Windows; it may compile under 16-bit Windows with a little

-   tweaking (or maybe not).  Thanks to Adam Costello and Pieter S. van der

-   Meulen for the "diamond" and "radial waves" patterns, respectively.

-

-   to do (someday, maybe):

-    - handle quoted command-line args (especially filenames with spaces)

-    - finish resizable checkerboard-gradient (sizes 4-128?)

-    - use %.1023s to simplify truncation of title-bar string?

-    - have minimum window width:  oh well

-

-  ---------------------------------------------------------------------------

-

-   Changelog:

-    - 1.01:  initial public release

-    - 1.02:  fixed cut-and-paste error in usage screen (oops...)

-    - 1.03:  modified to allow abbreviated options

-    - 1.04:  removed bogus extra argument from usage fprintf() [Glenn R-P?];

-              fixed command-line parsing bug

-    - 1.10:  enabled "message window"/console (thanks to David Geldreich)

-    - 1.20:  added runtime MMX-enabling/disabling and new -mmx* options

-    - 1.21:  made minor tweak to usage screen to fit within 25-line console

-    - 1.22:  added AMD64/EM64T support (__x86_64__)

-    - 2.00:  dual-licensed (added GNU GPL)

-    - 2.01:  fixed 64-bit typo in readpng2.c

-    - 2.02:  fixed improper display of usage screen on PNG error(s); fixed

-              unexpected-EOF and file-read-error cases

-    - 2.03:  removed runtime MMX-enabling/disabling and obsolete -mmx* options

-

-  ---------------------------------------------------------------------------

-

-      Copyright (c) 1998-2008 Greg Roelofs.  All rights reserved.

-

-      This software is provided "as is," without warranty of any kind,

-      express or implied.  In no event shall the author or contributors

-      be held liable for any damages arising in any way from the use of

-      this software.

-

-      The contents of this file are DUAL-LICENSED.  You may modify and/or

-      redistribute this software according to the terms of one of the

-      following two licenses (at your option):

-

-

-      LICENSE 1 ("BSD-like with advertising clause"):

-

-      Permission is granted to anyone to use this software for any purpose,

-      including commercial applications, and to alter it and redistribute

-      it freely, subject to the following restrictions:

-

-      1. Redistributions of source code must retain the above copyright

-         notice, disclaimer, and this list of conditions.

-      2. Redistributions in binary form must reproduce the above copyright

-         notice, disclaimer, and this list of conditions in the documenta-

-         tion and/or other materials provided with the distribution.

-      3. All advertising materials mentioning features or use of this

-         software must display the following acknowledgment:

-

-            This product includes software developed by Greg Roelofs

-            and contributors for the book, "PNG: The Definitive Guide,"

-            published by O'Reilly and Associates.

-

-

-      LICENSE 2 (GNU GPL v2 or later):

-

-      This program is free software; you can redistribute it and/or modify

-      it under the terms of the GNU General Public License as published by

-      the Free Software Foundation; either version 2 of the License, or

-      (at your option) any later version.

-

-      This program is distributed in the hope that it will be useful,

-      but WITHOUT ANY WARRANTY; without even the implied warranty of

-      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

-      GNU General Public License for more details.

-

-      You should have received a copy of the GNU General Public License

-      along with this program; if not, write to the Free Software Foundation,

-      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

-

-  ---------------------------------------------------------------------------*/

-

-#define PROGNAME  "rpng2-win"

-#define LONGNAME  "Progressive PNG Viewer for Windows"

-#define VERSION   "2.02 of 16 March 2008"

-

-#include <stdio.h>

-#include <stdlib.h>

-#include <string.h>

-#include <setjmp.h>    /* for jmpbuf declaration in readpng2.h */

-#include <time.h>

-#include <math.h>      /* only for PvdM background code */

-#include <windows.h>

-#ifdef __CYGWIN__

-/* getch replacement. Turns out, we don't really need this,

- * but leave it here if we ever enable any of the uses of

- * _getch in the main code

- */

-#include <unistd.h>

-#include <termio.h>

-#include <sys/ioctl.h>

-int repl_getch( void )

-{

-  char ch;

-  int fd = fileno(stdin);

-  struct termio old_tty, new_tty;

-

-  ioctl(fd, TCGETA, &old_tty);

-  new_tty = old_tty;

-  new_tty.c_lflag &= ~(ICANON | ECHO | ISIG);

-  ioctl(fd, TCSETA, &new_tty);

-  fread(&ch, 1, sizeof(ch), stdin);

-  ioctl(fd, TCSETA, &old_tty);

-

-  return ch;

-}

-#define _getch repl_getch

-#else

-#include <conio.h>     /* only for _getch() */

-#endif

-

-/* all for PvdM background code: */

-#ifndef PI

-#  define PI             3.141592653589793238

-#endif

-#define PI_2             (PI*0.5)

-#define INV_PI_360       (360.0 / PI)

-#define MAX(a,b)         (a>b?a:b)

-#define MIN(a,b)         (a<b?a:b)

-#define CLIP(a,min,max)  MAX(min,MIN((a),max))

-#define ABS(a)           ((a)<0?-(a):(a))

-#define CLIP8P(c)        MAX(0,(MIN((c),255)))   /* 8-bit pos. integer (uch) */

-#define ROUNDF(f)        ((int)(f + 0.5))

-

-#define rgb1_max   bg_freq

-#define rgb1_min   bg_gray

-#define rgb2_max   bg_bsat

-#define rgb2_min   bg_brot

-

-/* #define DEBUG */     /* this enables the Trace() macros */

-

-#include "readpng2.h"   /* typedefs, common macros, readpng2 prototypes */

-

-

-/* could just include png.h, but this macro is the only thing we need

- * (name and typedefs changed to local versions); note that side effects

- * only happen with alpha (which could easily be avoided with

- * "ush acopy = (alpha);") */

-

-#define alpha_composite(composite, fg, alpha, bg) {               \

-    ush temp = ((ush)(fg)*(ush)(alpha) +                          \

-                (ush)(bg)*(ush)(255 - (ush)(alpha)) + (ush)128);  \

-    (composite) = (uch)((temp + (temp >> 8)) >> 8);               \

-}

-

-

-#define INBUFSIZE 4096   /* with pseudo-timing on (1 sec delay/block), this

-                          *  block size corresponds roughly to a download

-                          *  speed 10% faster than theoretical 33.6K maximum

-                          *  (assuming 8 data bits, 1 stop bit and no other

-                          *  overhead) */

-

-/* local prototypes */

-static void       rpng2_win_init(void);

-static int        rpng2_win_create_window(void);

-static int        rpng2_win_load_bg_image(void);

-static void       rpng2_win_display_row(ulg row);

-static void       rpng2_win_finish_display(void);

-static void       rpng2_win_cleanup(void);

-LRESULT CALLBACK  rpng2_win_wndproc(HWND, UINT, WPARAM, LPARAM);

-

-

-static char titlebar[1024];

-static char *progname = PROGNAME;

-static char *appname = LONGNAME;

-static char *filename;

-static FILE *infile;

-

-static mainprog_info rpng2_info;

-

-static uch inbuf[INBUFSIZE];

-static int incount;

-

-static int pat = 6;         /* must be less than num_bgpat */

-static int bg_image = 0;

-static int bgscale = 16;

-static ulg bg_rowbytes;

-static uch *bg_data;

-

-static struct rgb_color {

-    uch r, g, b;

-} rgb[] = {

-    {  0,   0,   0},    /*  0:  black */

-    {255, 255, 255},    /*  1:  white */

-    {173, 132,  57},    /*  2:  tan */

-    { 64, 132,   0},    /*  3:  medium green */

-    {189, 117,   1},    /*  4:  gold */

-    {253, 249,   1},    /*  5:  yellow */

-    {  0,   0, 255},    /*  6:  blue */

-    {  0,   0, 120},    /*  7:  medium blue */

-    {255,   0, 255},    /*  8:  magenta */

-    { 64,   0,  64},    /*  9:  dark magenta */

-    {255,   0,   0},    /* 10:  red */

-    { 64,   0,   0},    /* 11:  dark red */

-    {255, 127,   0},    /* 12:  orange */

-    {192,  96,   0},    /* 13:  darker orange */

-    { 24,  60,   0},    /* 14:  dark green-yellow */

-    { 85, 125, 200}     /* 15:  ice blue */

-};

-/* not used for now, but should be for error-checking:

-static int num_rgb = sizeof(rgb) / sizeof(struct rgb_color);

- */

-

-/*

-    This whole struct is a fairly cheesy way to keep the number of

-    command-line options to a minimum.  The radial-waves background

-    type is a particularly poor fit to the integer elements of the

-    struct...but a few macros and a little fixed-point math will do

-    wonders for ya.

-

-    type bits:

-       F E D C B A 9 8 7 6 5 4 3 2 1 0

-                             | | | | |

-                             | | +-+-+-- 0 = sharp-edged checkerboard

-                             | |         1 = soft diamonds

-                             | |         2 = radial waves

-                             | |       3-7 = undefined

-                             | +-- gradient #2 inverted?

-                             +-- alternating columns inverted?

- */

-static struct background_pattern {

-    ush type;

-    int rgb1_max, rgb1_min;     /* or bg_freq, bg_gray */

-    int rgb2_max, rgb2_min;     /* or bg_bsat, bg_brot (both scaled by 10)*/

-} bg[] = {

-    {0+8,   2,0,  1,15},        /* checkered:  tan/black vs. white/ice blue */

-    {0+24,  2,0,  1,0},         /* checkered:  tan/black vs. white/black */

-    {0+8,   4,5,  0,2},         /* checkered:  gold/yellow vs. black/tan */

-    {0+8,   4,5,  0,6},         /* checkered:  gold/yellow vs. black/blue */

-    {0,     7,0,  8,9},         /* checkered:  deep blue/black vs. magenta */

-    {0+8,  13,0,  5,14},        /* checkered:  orange/black vs. yellow */

-    {0+8,  12,0, 10,11},        /* checkered:  orange/black vs. red */

-    {1,     7,0,  8,0},         /* diamonds:  deep blue/black vs. magenta */

-    {1,    12,0, 11,0},         /* diamonds:  orange vs. dark red */

-    {1,    10,0,  7,0},         /* diamonds:  red vs. medium blue */

-    {1,     4,0,  5,0},         /* diamonds:  gold vs. yellow */

-    {1,     3,0,  0,0},         /* diamonds:  medium green vs. black */

-    {2,    16, 100,  20,   0},  /* radial:  ~hard radial color-beams */

-    {2,    18, 100,  10,   2},  /* radial:  soft, curved radial color-beams */

-    {2,    16, 256, 100, 250},  /* radial:  very tight spiral */

-    {2, 10000, 256,  11,   0}   /* radial:  dipole-moire' (almost fractal) */

-};

-static int num_bgpat = sizeof(bg) / sizeof(struct background_pattern);

-

-

-/* Windows-specific global variables (could go in struct, but messy...) */

-static ulg wimage_rowbytes;

-static uch *dib;

-static uch *wimage_data;

-static BITMAPINFOHEADER *bmih;

-

-static HWND global_hwnd;

-static HINSTANCE global_hInst;

-static int global_showmode;

-

-

-

-

-int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, PSTR cmd, int showmode)

-{

-    char *args[1024];                 /* arbitrary limit, but should suffice */

-    char **argv = args;

-    char *p, *q, *bgstr = NULL;

-    int argc = 0;

-    int rc, alen, flen;

-    int error = 0;

-    int timing = FALSE;

-    int have_bg = FALSE;

-    double LUT_exponent;              /* just the lookup table */

-    double CRT_exponent = 2.2;        /* just the monitor */

-    double default_display_exponent;  /* whole display system */

-    MSG msg;

-

-

-    /* First initialize a few things, just to be sure--memset takes care of

-     * default background color (black), booleans (FALSE), pointers (NULL),

-     * etc. */

-

-    global_hInst = hInst;

-    global_showmode = showmode;

-    filename = (char *)NULL;

-    memset(&rpng2_info, 0, sizeof(mainprog_info));

-

-#ifndef __CYGWIN__

-    /* Next reenable console output, which normally goes to the bit bucket

-     * for windowed apps.  Closing the console window will terminate the

-     * app.  Thanks to David.Geldreich@realviz.com for supplying the magical

-     * incantation. */

-

-    AllocConsole();

-    freopen("CONOUT$", "a", stderr);

-    freopen("CONOUT$", "a", stdout);

-#endif

-

-    /* Set the default value for our display-system exponent, i.e., the

-     * product of the CRT exponent and the exponent corresponding to

-     * the frame-buffer's lookup table (LUT), if any.  This is not an

-     * exhaustive list of LUT values (e.g., OpenStep has a lot of weird

-     * ones), but it should cover 99% of the current possibilities.  And

-     * yes, these ifdefs are completely wasted in a Windows program... */

-

-#if defined(NeXT)

-    /* third-party utilities can modify the default LUT exponent */

-    LUT_exponent = 1.0 / 2.2;

-    /*

-    if (some_next_function_that_returns_gamma(&next_gamma))

-        LUT_exponent = 1.0 / next_gamma;

-     */

-#elif defined(sgi)

-    LUT_exponent = 1.0 / 1.7;

-    /* there doesn't seem to be any documented function to

-     * get the "gamma" value, so we do it the hard way */

-    infile = fopen("/etc/config/system.glGammaVal", "r");

-    if (infile) {

-        double sgi_gamma;

-

-        fgets(tmpline, 80, infile);

-        fclose(infile);

-        sgi_gamma = atof(tmpline);

-        if (sgi_gamma > 0.0)

-            LUT_exponent = 1.0 / sgi_gamma;

-    }

-#elif defined(Macintosh)

-    LUT_exponent = 1.8 / 2.61;

-    /*

-    if (some_mac_function_that_returns_gamma(&mac_gamma))

-        LUT_exponent = mac_gamma / 2.61;

-     */

-#else

-    LUT_exponent = 1.0;   /* assume no LUT:  most PCs */

-#endif

-

-    /* the defaults above give 1.0, 1.3, 1.5 and 2.2, respectively: */

-    default_display_exponent = LUT_exponent * CRT_exponent;

-

-

-    /* If the user has set the SCREEN_GAMMA environment variable as suggested

-     * (somewhat imprecisely) in the libpng documentation, use that; otherwise

-     * use the default value we just calculated.  Either way, the user may

-     * override this via a command-line option. */

-

-    if ((p = getenv("SCREEN_GAMMA")) != NULL)

-        rpng2_info.display_exponent = atof(p);

-    else

-        rpng2_info.display_exponent = default_display_exponent;

-

-

-    /* Windows really hates command lines, so we have to set up our own argv.

-     * Note that we do NOT bother with quoted arguments here, so don't use

-     * filenames with spaces in 'em! */

-

-    argv[argc++] = PROGNAME;

-    p = cmd;

-    for (;;) {

-        if (*p == ' ')

-            while (*++p == ' ')

-                ;

-        /* now p points at the first non-space after some spaces */

-        if (*p == '\0')

-            break;    /* nothing after the spaces:  done */

-        argv[argc++] = q = p;

-        while (*q && *q != ' ')

-            ++q;

-        /* now q points at a space or the end of the string */

-        if (*q == '\0')

-            break;    /* last argv already terminated; quit */

-        *q = '\0';    /* change space to terminator */

-        p = q + 1;

-    }

-    argv[argc] = NULL;   /* terminate the argv array itself */

-

-

-    /* Now parse the command line for options and the PNG filename. */

-

-    while (*++argv && !error) {

-        if (!strncmp(*argv, "-gamma", 2)) {

-            if (!*++argv)

-                ++error;

-            else {

-                rpng2_info.display_exponent = atof(*argv);

-                if (rpng2_info.display_exponent <= 0.0)

-                    ++error;

-            }

-        } else if (!strncmp(*argv, "-bgcolor", 4)) {

-            if (!*++argv)

-                ++error;

-            else {

-                bgstr = *argv;

-                if (strlen(bgstr) != 7 || bgstr[0] != '#')

-                    ++error;

-                else {

-                    have_bg = TRUE;

-                    bg_image = FALSE;

-                }

-            }

-        } else if (!strncmp(*argv, "-bgpat", 4)) {

-            if (!*++argv)

-                ++error;

-            else {

-                pat = atoi(*argv) - 1;

-                if (pat < 0 || pat >= num_bgpat)

-                    ++error;

-                else {

-                    bg_image = TRUE;

-                    have_bg = FALSE;

-                }

-            }

-        } else if (!strncmp(*argv, "-timing", 2)) {

-            timing = TRUE;

-        } else {

-            if (**argv != '-') {

-                filename = *argv;

-                if (argv[1])   /* shouldn't be any more args after filename */

-                    ++error;

-            } else

-                ++error;   /* not expecting any other options */

-        }

-    }

-

-    if (!filename)

-        ++error;

-

-

-    /* print usage screen if any errors up to this point */

-

-    if (error) {

-#ifndef __CYGWIN__

-        int ch;

-#endif

-

-        fprintf(stderr, "\n%s %s:  %s\n\n", PROGNAME, VERSION, appname);

-        readpng2_version_info();

-        fprintf(stderr, "\n"

-          "Usage:  %s [-gamma exp] [-bgcolor bg | -bgpat pat] [-timing]\n"

-          "        %*s file.png\n\n"

-          "    exp \ttransfer-function exponent (``gamma'') of the display\n"

-          "\t\t  system in floating-point format (e.g., ``%.1f''); equal\n"

-          "\t\t  to the product of the lookup-table exponent (varies)\n"

-          "\t\t  and the CRT exponent (usually 2.2); must be positive\n"

-          "    bg  \tdesired background color in 7-character hex RGB format\n"

-          "\t\t  (e.g., ``#ff7700'' for orange:  same as HTML colors);\n"

-          "\t\t  used with transparent images; overrides -bgpat option\n"

-          "    pat \tdesired background pattern number (1-%d); used with\n"

-          "\t\t  transparent images; overrides -bgcolor option\n"

-          "    -timing\tenables delay for every block read, to simulate modem\n"

-          "\t\t  download of image (~36 Kbps)\n"

-          "\nPress Q, Esc or mouse button 1 after image is displayed to quit.\n"

-#ifndef __CYGWIN__

-          "Press Q or Esc to quit this usage screen. ",

-#else

-          ,

-#endif

-          PROGNAME,

-#if (defined(__i386__) || defined(_M_IX86) || defined(__x86_64__)) && \

-    !(defined(__CYGWIN__) || defined(__MINGW32__))

-          (int)strlen(PROGNAME), " ",

-#endif

-          (int)strlen(PROGNAME), " ", default_display_exponent, num_bgpat);

-        fflush(stderr);

-#ifndef __CYGWIN__

-        do

-            ch = _getch();

-        while (ch != 'q' && ch != 'Q' && ch != 0x1B);

-#endif

-        exit(1);

-    }

-

-

-    if (!(infile = fopen(filename, "rb"))) {

-        fprintf(stderr, PROGNAME ":  can't open PNG file [%s]\n", filename);

-        ++error;

-    } else {

-        incount = fread(inbuf, 1, INBUFSIZE, infile);

-        if (incount < 8 || !readpng2_check_sig(inbuf, 8)) {

-            fprintf(stderr, PROGNAME

-              ":  [%s] is not a PNG file: incorrect signature\n",

-              filename);

-            ++error;

-        } else if ((rc = readpng2_init(&rpng2_info)) != 0) {

-            switch (rc) {

-                case 2:

-                    fprintf(stderr, PROGNAME

-                      ":  [%s] has bad IHDR (libpng longjmp)\n", filename);

-                    break;

-                case 4:

-                    fprintf(stderr, PROGNAME ":  insufficient memory\n");

-                    break;

-                default:

-                    fprintf(stderr, PROGNAME

-                      ":  unknown readpng2_init() error\n");

-                    break;

-            }

-            ++error;

-        }

-        if (error)

-            fclose(infile);

-    }

-

-

-    if (error) {

-#ifndef __CYGWIN__

-        int ch;

-#endif

-

-        fprintf(stderr, PROGNAME ":  aborting.\n");

-#ifndef __CYGWIN__

-        do

-            ch = _getch();

-        while (ch != 'q' && ch != 'Q' && ch != 0x1B);

-#endif

-        exit(2);

-    } else {

-        fprintf(stderr, "\n%s %s:  %s\n", PROGNAME, VERSION, appname);

-#ifndef __CYGWIN__

-        fprintf(stderr,

-          "\n   [console window:  closing this window will terminate %s]\n\n",

-          PROGNAME);

-#endif

-        fflush(stderr);

-    }

-

-

-    /* set the title-bar string, but make sure buffer doesn't overflow */

-

-    alen = strlen(appname);

-    flen = strlen(filename);

-    if (alen + flen + 3 > 1023)

-        sprintf(titlebar, "%s:  ...%s", appname, filename+(alen+flen+6-1023));

-    else

-        sprintf(titlebar, "%s:  %s", appname, filename);

-

-

-    /* set some final rpng2_info variables before entering main data loop */

-

-    if (have_bg) {

-        unsigned r, g, b;   /* this approach quiets compiler warnings */

-

-        sscanf(bgstr+1, "%2x%2x%2x", &r, &g, &b);

-        rpng2_info.bg_red   = (uch)r;

-        rpng2_info.bg_green = (uch)g;

-        rpng2_info.bg_blue  = (uch)b;

-    } else

-        rpng2_info.need_bgcolor = TRUE;

-

-    rpng2_info.state = kPreInit;

-    rpng2_info.mainprog_init = rpng2_win_init;

-    rpng2_info.mainprog_display_row = rpng2_win_display_row;

-    rpng2_info.mainprog_finish_display = rpng2_win_finish_display;

-

-

-    /* OK, this is the fun part:  call readpng2_decode_data() at the start of

-     * the loop to deal with our first buffer of data (read in above to verify

-     * that the file is a PNG image), then loop through the file and continue

-     * calling the same routine to handle each chunk of data.  It in turn

-     * passes the data to libpng, which will invoke one or more of our call-

-     * backs as decoded data become available.  We optionally call Sleep() for

-     * one second per iteration to simulate downloading the image via an analog

-     * modem. */

-

-    for (;;) {

-        Trace((stderr, "about to call readpng2_decode_data()\n"))

-        if (readpng2_decode_data(&rpng2_info, inbuf, incount))

-            ++error;

-        Trace((stderr, "done with readpng2_decode_data()\n"))

-

-        if (error || incount != INBUFSIZE || rpng2_info.state == kDone) {

-            if (rpng2_info.state == kDone) {

-                Trace((stderr, "done decoding PNG image\n"))

-            } else if (ferror(infile)) {

-                fprintf(stderr, PROGNAME

-                  ":  error while reading PNG image file\n");

-                exit(3);

-            } else if (feof(infile)) {

-                fprintf(stderr, PROGNAME ":  end of file reached "

-                  "(unexpectedly) while reading PNG image file\n");

-                exit(3);

-            } else /* if (error) */ {

-                /* will print error message below */

-            }

-            break;

-        }

-

-        if (timing)

-            Sleep(1000L);

-

-        incount = fread(inbuf, 1, INBUFSIZE, infile);

-    }

-

-

-    /* clean up PNG stuff and report any decoding errors */

-

-    fclose(infile);

-    Trace((stderr, "about to call readpng2_cleanup()\n"))

-    readpng2_cleanup(&rpng2_info);

-

-    if (error) {

-        fprintf(stderr, PROGNAME ":  libpng error while decoding PNG image\n");

-        exit(3);

-    }

-

-

-    /* wait for the user to tell us when to quit */

-

-    while (GetMessage(&msg, NULL, 0, 0)) {

-        TranslateMessage(&msg);

-        DispatchMessage(&msg);

-    }

-

-

-    /* we're done:  clean up all image and Windows resources and go away */

-

-    Trace((stderr, "about to call rpng2_win_cleanup()\n"))

-    rpng2_win_cleanup();

-

-    return msg.wParam;

-}

-

-

-

-

-

-/* this function is called by readpng2_info_callback() in readpng2.c, which

- * in turn is called by libpng after all of the pre-IDAT chunks have been

- * read and processed--i.e., we now have enough info to finish initializing */

-

-static void rpng2_win_init()

-{

-    ulg i;

-    ulg rowbytes = rpng2_info.rowbytes;

-

-    Trace((stderr, "beginning rpng2_win_init()\n"))

-    Trace((stderr, "  rowbytes = %d\n", rpng2_info.rowbytes))

-    Trace((stderr, "  width  = %ld\n", rpng2_info.width))

-    Trace((stderr, "  height = %ld\n", rpng2_info.height))

-

-    rpng2_info.image_data = (uch *)malloc(rowbytes * rpng2_info.height);

-    if (!rpng2_info.image_data) {

-        readpng2_cleanup(&rpng2_info);

-        return;

-    }

-

-    rpng2_info.row_pointers = (uch **)malloc(rpng2_info.height * sizeof(uch *));

-    if (!rpng2_info.row_pointers) {

-        free(rpng2_info.image_data);

-        rpng2_info.image_data = NULL;

-        readpng2_cleanup(&rpng2_info);

-        return;

-    }

-

-    for (i = 0;  i < rpng2_info.height;  ++i)

-        rpng2_info.row_pointers[i] = rpng2_info.image_data + i*rowbytes;

-

-/*---------------------------------------------------------------------------

-    Do the basic Windows initialization stuff, make the window, and fill it

-    with the user-specified, file-specified or default background color.

-  ---------------------------------------------------------------------------*/

-

-    if (rpng2_win_create_window()) {

-        readpng2_cleanup(&rpng2_info);

-        return;

-    }

-

-    rpng2_info.state = kWindowInit;

-}

-

-

-

-

-

-static int rpng2_win_create_window()

-{

-    uch bg_red   = rpng2_info.bg_red;

-    uch bg_green = rpng2_info.bg_green;

-    uch bg_blue  = rpng2_info.bg_blue;

-    uch *dest;

-    int extra_width, extra_height;

-    ulg i, j;

-    WNDCLASSEX wndclass;

-    RECT rect;

-

-

-/*---------------------------------------------------------------------------

-    Allocate memory for the display-specific version of the image (round up

-    to multiple of 4 for Windows DIB).

-  ---------------------------------------------------------------------------*/

-

-    wimage_rowbytes = ((3*rpng2_info.width + 3L) >> 2) << 2;

-

-    if (!(dib = (uch *)malloc(sizeof(BITMAPINFOHEADER) +

-                              wimage_rowbytes*rpng2_info.height)))

-    {

-        return 4;   /* fail */

-    }

-

-/*---------------------------------------------------------------------------

-    Initialize the DIB.  Negative height means to use top-down BMP ordering

-    (must be uncompressed, but that's what we want).  Bit count of 1, 4 or 8

-    implies a colormap of RGBX quads, but 24-bit BMPs just use B,G,R values

-    directly => wimage_data begins immediately after BMP header.

-  ---------------------------------------------------------------------------*/

-

-    memset(dib, 0, sizeof(BITMAPINFOHEADER));

-    bmih = (BITMAPINFOHEADER *)dib;

-    bmih->biSize = sizeof(BITMAPINFOHEADER);

-    bmih->biWidth = rpng2_info.width;

-    bmih->biHeight = -((long)rpng2_info.height);

-    bmih->biPlanes = 1;

-    bmih->biBitCount = 24;

-    bmih->biCompression = 0;

-    wimage_data = dib + sizeof(BITMAPINFOHEADER);

-

-/*---------------------------------------------------------------------------

-    Fill window with the specified background color (default is black), but

-    defer loading faked "background image" until window is displayed (may be

-    slow to compute).  Data are in BGR order.

-  ---------------------------------------------------------------------------*/

-

-    if (bg_image) {   /* just fill with black for now */

-        memset(wimage_data, 0, wimage_rowbytes*rpng2_info.height);

-    } else {

-        for (j = 0;  j < rpng2_info.height;  ++j) {

-            dest = wimage_data + j*wimage_rowbytes;

-            for (i = rpng2_info.width;  i > 0;  --i) {

-                *dest++ = bg_blue;

-                *dest++ = bg_green;

-                *dest++ = bg_red;

-            }

-        }

-    }

-

-/*---------------------------------------------------------------------------

-    Set the window parameters.

-  ---------------------------------------------------------------------------*/

-

-    memset(&wndclass, 0, sizeof(wndclass));

-

-    wndclass.cbSize = sizeof(wndclass);

-    wndclass.style = CS_HREDRAW | CS_VREDRAW;

-    wndclass.lpfnWndProc = rpng2_win_wndproc;

-    wndclass.hInstance = global_hInst;

-    wndclass.hIcon = LoadIcon(NULL, IDI_APPLICATION);

-    wndclass.hCursor = LoadCursor(NULL, IDC_ARROW);

-    wndclass.hbrBackground = (HBRUSH)GetStockObject(DKGRAY_BRUSH);

-    wndclass.lpszMenuName = NULL;

-    wndclass.lpszClassName = progname;

-    wndclass.hIconSm = LoadIcon(NULL, IDI_APPLICATION);

-

-    RegisterClassEx(&wndclass);

-

-/*---------------------------------------------------------------------------

-    Finally, create the window.

-  ---------------------------------------------------------------------------*/

-

-    extra_width  = 2*(GetSystemMetrics(SM_CXBORDER) +

-                      GetSystemMetrics(SM_CXDLGFRAME));

-    extra_height = 2*(GetSystemMetrics(SM_CYBORDER) +

-                      GetSystemMetrics(SM_CYDLGFRAME)) +

-                      GetSystemMetrics(SM_CYCAPTION);

-

-    global_hwnd = CreateWindow(progname, titlebar, WS_OVERLAPPEDWINDOW,

-      CW_USEDEFAULT, CW_USEDEFAULT, rpng2_info.width+extra_width,

-      rpng2_info.height+extra_height, NULL, NULL, global_hInst, NULL);

-

-    ShowWindow(global_hwnd, global_showmode);

-    UpdateWindow(global_hwnd);

-

-/*---------------------------------------------------------------------------

-    Now compute the background image and display it.  If it fails (memory

-    allocation), revert to a plain background color.

-  ---------------------------------------------------------------------------*/

-

-    if (bg_image) {

-        static const char *msg = "Computing background image...";

-        int x, y, len = strlen(msg);

-        HDC hdc = GetDC(global_hwnd);

-        TEXTMETRIC tm;

-

-        GetTextMetrics(hdc, &tm);

-        x = (rpng2_info.width - len*tm.tmAveCharWidth)/2;

-        y = (rpng2_info.height - tm.tmHeight)/2;

-        SetBkMode(hdc, TRANSPARENT);

-        SetTextColor(hdc, GetSysColor(COLOR_HIGHLIGHTTEXT));

-        /* this can still begin out of bounds even if x is positive (???): */

-        TextOut(hdc, ((x < 0)? 0 : x), ((y < 0)? 0 : y), msg, len);

-        ReleaseDC(global_hwnd, hdc);

-

-        rpng2_win_load_bg_image();   /* resets bg_image if fails */

-    }

-

-    if (!bg_image) {

-        for (j = 0;  j < rpng2_info.height;  ++j) {

-            dest = wimage_data + j*wimage_rowbytes;

-            for (i = rpng2_info.width;  i > 0;  --i) {

-                *dest++ = bg_blue;

-                *dest++ = bg_green;

-                *dest++ = bg_red;

-            }

-        }

-    }

-

-    rect.left = 0L;

-    rect.top = 0L;

-    rect.right = (LONG)rpng2_info.width;       /* possibly off by one? */

-    rect.bottom = (LONG)rpng2_info.height;     /* possibly off by one? */

-    InvalidateRect(global_hwnd, &rect, FALSE);

-    UpdateWindow(global_hwnd);                 /* similar to XFlush() */

-

-    return 0;

-

-} /* end function rpng2_win_create_window() */

-

-

-

-

-

-static int rpng2_win_load_bg_image()

-{

-    uch *src, *dest;

-    uch r1, r2, g1, g2, b1, b2;

-    uch r1_inv, r2_inv, g1_inv, g2_inv, b1_inv, b2_inv;

-    int k, hmax, max;

-    int xidx, yidx, yidx_max = (bgscale-1);

-    int even_odd_vert, even_odd_horiz, even_odd;

-    int invert_gradient2 = (bg[pat].type & 0x08);

-    int invert_column;

-    ulg i, row;

-

-/*---------------------------------------------------------------------------

-    Allocate buffer for fake background image to be used with transparent

-    images; if this fails, revert to plain background color.

-  ---------------------------------------------------------------------------*/

-

-    bg_rowbytes = 3 * rpng2_info.width;

-    bg_data = (uch *)malloc(bg_rowbytes * rpng2_info.height);

-    if (!bg_data) {

-        fprintf(stderr, PROGNAME

-          ":  unable to allocate memory for background image\n");

-        bg_image = 0;

-        return 1;

-    }

-

-/*---------------------------------------------------------------------------

-    Vertical gradients (ramps) in NxN squares, alternating direction and

-    colors (N == bgscale).

-  ---------------------------------------------------------------------------*/

-

-    if ((bg[pat].type & 0x07) == 0) {

-        uch r1_min  = rgb[bg[pat].rgb1_min].r;

-        uch g1_min  = rgb[bg[pat].rgb1_min].g;

-        uch b1_min  = rgb[bg[pat].rgb1_min].b;

-        uch r2_min  = rgb[bg[pat].rgb2_min].r;

-        uch g2_min  = rgb[bg[pat].rgb2_min].g;

-        uch b2_min  = rgb[bg[pat].rgb2_min].b;

-        int r1_diff = rgb[bg[pat].rgb1_max].r - r1_min;

-        int g1_diff = rgb[bg[pat].rgb1_max].g - g1_min;

-        int b1_diff = rgb[bg[pat].rgb1_max].b - b1_min;

-        int r2_diff = rgb[bg[pat].rgb2_max].r - r2_min;

-        int g2_diff = rgb[bg[pat].rgb2_max].g - g2_min;

-        int b2_diff = rgb[bg[pat].rgb2_max].b - b2_min;

-

-        for (row = 0;  row < rpng2_info.height;  ++row) {

-            yidx = row % bgscale;

-            even_odd_vert = (row / bgscale) & 1;

-

-            r1 = r1_min + (r1_diff * yidx) / yidx_max;

-            g1 = g1_min + (g1_diff * yidx) / yidx_max;

-            b1 = b1_min + (b1_diff * yidx) / yidx_max;

-            r1_inv = r1_min + (r1_diff * (yidx_max-yidx)) / yidx_max;

-            g1_inv = g1_min + (g1_diff * (yidx_max-yidx)) / yidx_max;

-            b1_inv = b1_min + (b1_diff * (yidx_max-yidx)) / yidx_max;

-

-            r2 = r2_min + (r2_diff * yidx) / yidx_max;

-            g2 = g2_min + (g2_diff * yidx) / yidx_max;

-            b2 = b2_min + (b2_diff * yidx) / yidx_max;

-            r2_inv = r2_min + (r2_diff * (yidx_max-yidx)) / yidx_max;

-            g2_inv = g2_min + (g2_diff * (yidx_max-yidx)) / yidx_max;

-            b2_inv = b2_min + (b2_diff * (yidx_max-yidx)) / yidx_max;

-

-            dest = bg_data + row*bg_rowbytes;

-            for (i = 0;  i < rpng2_info.width;  ++i) {

-                even_odd_horiz = (i / bgscale) & 1;

-                even_odd = even_odd_vert ^ even_odd_horiz;

-                invert_column =

-                  (even_odd_horiz && (bg[pat].type & 0x10));

-                if (even_odd == 0) {         /* gradient #1 */

-                    if (invert_column) {

-                        *dest++ = r1_inv;

-                        *dest++ = g1_inv;

-                        *dest++ = b1_inv;

-                    } else {

-                        *dest++ = r1;

-                        *dest++ = g1;

-                        *dest++ = b1;

-                    }

-                } else {                     /* gradient #2 */

-                    if ((invert_column && invert_gradient2) ||

-                        (!invert_column && !invert_gradient2))

-                    {

-                        *dest++ = r2;        /* not inverted or */

-                        *dest++ = g2;        /*  doubly inverted */

-                        *dest++ = b2;

-                    } else {

-                        *dest++ = r2_inv;

-                        *dest++ = g2_inv;    /* singly inverted */

-                        *dest++ = b2_inv;

-                    }

-                }

-            }

-        }

-

-/*---------------------------------------------------------------------------

-    Soft gradient-diamonds with scale = bgscale.  Code contributed by Adam

-    M. Costello.

-  ---------------------------------------------------------------------------*/

-

-    } else if ((bg[pat].type & 0x07) == 1) {

-

-        hmax = (bgscale-1)/2;   /* half the max weight of a color */

-        max = 2*hmax;           /* the max weight of a color */

-

-        r1 = rgb[bg[pat].rgb1_max].r;

-        g1 = rgb[bg[pat].rgb1_max].g;

-        b1 = rgb[bg[pat].rgb1_max].b;

-        r2 = rgb[bg[pat].rgb2_max].r;

-        g2 = rgb[bg[pat].rgb2_max].g;

-        b2 = rgb[bg[pat].rgb2_max].b;

-

-        for (row = 0;  row < rpng2_info.height;  ++row) {

-            yidx = row % bgscale;

-            if (yidx > hmax)

-                yidx = bgscale-1 - yidx;

-            dest = bg_data + row*bg_rowbytes;

-            for (i = 0;  i < rpng2_info.width;  ++i) {

-                xidx = i % bgscale;

-                if (xidx > hmax)

-                    xidx = bgscale-1 - xidx;

-                k = xidx + yidx;

-                *dest++ = (k*r1 + (max-k)*r2) / max;

-                *dest++ = (k*g1 + (max-k)*g2) / max;

-                *dest++ = (k*b1 + (max-k)*b2) / max;

-            }

-        }

-

-/*---------------------------------------------------------------------------

-    Radial "starburst" with azimuthal sinusoids; [eventually number of sinu-

-    soids will equal bgscale?].  This one is slow but very cool.  Code con-

-    tributed by Pieter S. van der Meulen (originally in Smalltalk).

-  ---------------------------------------------------------------------------*/

-

-    } else if ((bg[pat].type & 0x07) == 2) {

-        uch ch;

-        int ii, x, y, hw, hh, grayspot;

-        double freq, rotate, saturate, gray, intensity;

-        double angle=0.0, aoffset=0.0, maxDist, dist;

-        double red=0.0, green=0.0, blue=0.0, hue, s, v, f, p, q, t;

-

-        fprintf(stderr, "%s:  computing radial background...",

-          PROGNAME);

-        fflush(stderr);

-

-        hh = rpng2_info.height / 2;

-        hw = rpng2_info.width / 2;

-

-        /* variables for radial waves:

-         *   aoffset:  number of degrees to rotate hue [CURRENTLY NOT USED]

-         *   freq:  number of color beams originating from the center

-         *   grayspot:  size of the graying center area (anti-alias)

-         *   rotate:  rotation of the beams as a function of radius

-         *   saturate:  saturation of beams' shape azimuthally

-         */

-        angle = CLIP(angle, 0.0, 360.0);

-        grayspot = CLIP(bg[pat].bg_gray, 1, (hh + hw));

-        freq = MAX((double)bg[pat].bg_freq, 0.0);

-        saturate = (double)bg[pat].bg_bsat * 0.1;

-        rotate = (double)bg[pat].bg_brot * 0.1;

-        gray = 0.0;

-        intensity = 0.0;

-        maxDist = (double)((hw*hw) + (hh*hh));

-

-        for (row = 0;  row < rpng2_info.height;  ++row) {

-            y = row - hh;

-            dest = bg_data + row*bg_rowbytes;

-            for (i = 0;  i < rpng2_info.width;  ++i) {

-                x = i - hw;

-                angle = (x == 0)? PI_2 : atan((double)y / (double)x);

-                gray = (double)MAX(ABS(y), ABS(x)) / grayspot;

-                gray = MIN(1.0, gray);

-                dist = (double)((x*x) + (y*y)) / maxDist;

-                intensity = cos((angle+(rotate*dist*PI)) * freq) *

-                  gray * saturate;

-                intensity = (MAX(MIN(intensity,1.0),-1.0) + 1.0) * 0.5;

-                hue = (angle + PI) * INV_PI_360 + aoffset;

-                s = gray * ((double)(ABS(x)+ABS(y)) / (double)(hw + hh));

-                s = MIN(MAX(s,0.0), 1.0);

-                v = MIN(MAX(intensity,0.0), 1.0);

-

-                if (s == 0.0) {

-                    ch = (uch)(v * 255.0);

-                    *dest++ = ch;

-                    *dest++ = ch;

-                    *dest++ = ch;

-                } else {

-                    if ((hue < 0.0) || (hue >= 360.0))

-                        hue -= (((int)(hue / 360.0)) * 360.0);

-                    hue /= 60.0;

-                    ii = (int)hue;

-                    f = hue - (double)ii;

-                    p = (1.0 - s) * v;

-                    q = (1.0 - (s * f)) * v;

-                    t = (1.0 - (s * (1.0 - f))) * v;

-                    if      (ii == 0) { red = v; green = t; blue = p; }

-                    else if (ii == 1) { red = q; green = v; blue = p; }

-                    else if (ii == 2) { red = p; green = v; blue = t; }

-                    else if (ii == 3) { red = p; green = q; blue = v; }

-                    else if (ii == 4) { red = t; green = p; blue = v; }

-                    else if (ii == 5) { red = v; green = p; blue = q; }

-                    *dest++ = (uch)(red * 255.0);

-                    *dest++ = (uch)(green * 255.0);

-                    *dest++ = (uch)(blue * 255.0);

-                }

-            }

-        }

-        fprintf(stderr, "done.\n");

-        fflush(stderr);

-    }

-

-/*---------------------------------------------------------------------------

-    Blast background image to display buffer before beginning PNG decode;

-    calling function will handle invalidation and UpdateWindow() call.

-  ---------------------------------------------------------------------------*/

-

-    for (row = 0;  row < rpng2_info.height;  ++row) {

-        src = bg_data + row*bg_rowbytes;

-        dest = wimage_data + row*wimage_rowbytes;

-        for (i = rpng2_info.width;  i > 0;  --i) {

-            r1 = *src++;

-            g1 = *src++;

-            b1 = *src++;

-            *dest++ = b1;

-            *dest++ = g1;   /* note reverse order */

-            *dest++ = r1;

-        }

-    }

-

-    return 0;

-

-} /* end function rpng2_win_load_bg_image() */

-

-

-

-

-

-static void rpng2_win_display_row(ulg row)

-{

-    uch bg_red   = rpng2_info.bg_red;

-    uch bg_green = rpng2_info.bg_green;

-    uch bg_blue  = rpng2_info.bg_blue;

-    uch *src, *src2=NULL, *dest;

-    uch r, g, b, a;

-    ulg i;

-    static int rows=0;

-    static ulg firstrow;

-

-/*---------------------------------------------------------------------------

-    rows and firstrow simply track how many rows (and which ones) have not

-    yet been displayed; alternatively, we could call InvalidateRect() for

-    every row and not bother with the records-keeping.

-  ---------------------------------------------------------------------------*/

-

-    Trace((stderr, "beginning rpng2_win_display_row()\n"))

-

-    if (rows == 0)

-        firstrow = row;   /* first row not yet displayed */

-

-    ++rows;   /* count of rows received but not yet displayed */

-

-/*---------------------------------------------------------------------------

-    Aside from the use of the rpng2_info struct and the lack of an outer

-    loop (over rows), this routine is identical to rpng_win_display_image()

-    in the non-progressive version of the program.

-  ---------------------------------------------------------------------------*/

-

-    src = rpng2_info.image_data + row*rpng2_info.rowbytes;

-    if (bg_image)

-        src2 = bg_data + row*bg_rowbytes;

-    dest = wimage_data + row*wimage_rowbytes;

-

-    if (rpng2_info.channels == 3) {

-        for (i = rpng2_info.width;  i > 0;  --i) {

-            r = *src++;

-            g = *src++;

-            b = *src++;

-            *dest++ = b;

-            *dest++ = g;   /* note reverse order */

-            *dest++ = r;

-        }

-    } else /* if (rpng2_info.channels == 4) */ {

-        for (i = rpng2_info.width;  i > 0;  --i) {

-            r = *src++;

-            g = *src++;

-            b = *src++;

-            a = *src++;

-            if (bg_image) {

-                bg_red   = *src2++;

-                bg_green = *src2++;

-                bg_blue  = *src2++;

-            }

-            if (a == 255) {

-                *dest++ = b;

-                *dest++ = g;

-                *dest++ = r;

-            } else if (a == 0) {

-                *dest++ = bg_blue;

-                *dest++ = bg_green;

-                *dest++ = bg_red;

-            } else {

-                /* this macro (copied from png.h) composites the

-                 * foreground and background values and puts the

-                 * result into the first argument; there are no

-                 * side effects with the first argument */

-                alpha_composite(*dest++, b, a, bg_blue);

-                alpha_composite(*dest++, g, a, bg_green);

-                alpha_composite(*dest++, r, a, bg_red);

-            }

-        }

-    }

-

-/*---------------------------------------------------------------------------

-    Display after every 16 rows or when on last row.  (Region may include

-    previously displayed lines due to interlacing--i.e., not contiguous.)

-  ---------------------------------------------------------------------------*/

-

-    if ((rows & 0xf) == 0 || row == rpng2_info.height-1) {

-        RECT rect;

-

-        rect.left = 0L;

-        rect.top = (LONG)firstrow;

-        rect.right = (LONG)rpng2_info.width;       /* possibly off by one? */

-        rect.bottom = (LONG)row + 1L;              /* possibly off by one? */

-        InvalidateRect(global_hwnd, &rect, FALSE);

-        UpdateWindow(global_hwnd);                 /* similar to XFlush() */

-        rows = 0;

-    }

-

-} /* end function rpng2_win_display_row() */

-

-

-

-

-

-static void rpng2_win_finish_display()

-{

-    Trace((stderr, "beginning rpng2_win_finish_display()\n"))

-

-    /* last row has already been displayed by rpng2_win_display_row(), so

-     * we have nothing to do here except set a flag and let the user know

-     * that the image is done */

-

-    rpng2_info.state = kDone;

-    printf(

-#ifndef __CYGWIN__

-      "Done.  Press Q, Esc or mouse button 1 (within image window) to quit.\n"

-#else

-      "Done.  Press mouse button 1 (within image window) to quit.\n"

-#endif

-    );

-    fflush(stdout);

-}

-

-

-

-

-

-static void rpng2_win_cleanup()

-{

-    if (bg_image && bg_data) {

-        free(bg_data);

-        bg_data = NULL;

-    }

-

-    if (rpng2_info.image_data) {

-        free(rpng2_info.image_data);

-        rpng2_info.image_data = NULL;

-    }

-

-    if (rpng2_info.row_pointers) {

-        free(rpng2_info.row_pointers);

-        rpng2_info.row_pointers = NULL;

-    }

-

-    if (dib) {

-        free(dib);

-        dib = NULL;

-    }

-}

-

-

-

-

-

-LRESULT CALLBACK rpng2_win_wndproc(HWND hwnd, UINT iMsg, WPARAM wP, LPARAM lP)

-{

-    HDC         hdc;

-    PAINTSTRUCT ps;

-    int rc;

-

-    switch (iMsg) {

-        case WM_CREATE:

-            /* one-time processing here, if any */

-            return 0;

-

-        case WM_PAINT:

-            hdc = BeginPaint(hwnd, &ps);

-            rc = StretchDIBits(hdc, 0, 0, rpng2_info.width, rpng2_info.height,

-                                    0, 0, rpng2_info.width, rpng2_info.height,

-                                    wimage_data, (BITMAPINFO *)bmih,

-                                    0, SRCCOPY);

-            EndPaint(hwnd, &ps);

-            return 0;

-

-        /* wait for the user to tell us when to quit */

-        case WM_CHAR:

-            switch (wP) {       /* only need one, so ignore repeat count */

-                case 'q':

-                case 'Q':

-                case 0x1B:      /* Esc key */

-                    PostQuitMessage(0);

-            }

-            return 0;

-

-        case WM_LBUTTONDOWN:    /* another way of quitting */

-        case WM_DESTROY:

-            PostQuitMessage(0);

-            return 0;

-    }

-

-    return DefWindowProc(hwnd, iMsg, wP, lP);

-}

+/*---------------------------------------------------------------------------
+
+   rpng2 - progressive-model PNG display program                rpng2-win.c
+
+   This program decodes and displays PNG files progressively, as if it were
+   a web browser (though the front end is only set up to read from files).
+   It supports gamma correction, user-specified background colors, and user-
+   specified background patterns (for transparent images).  This version is
+   for 32-bit Windows; it may compile under 16-bit Windows with a little
+   tweaking (or maybe not).  Thanks to Adam Costello and Pieter S. van der
+   Meulen for the "diamond" and "radial waves" patterns, respectively.
+
+   to do (someday, maybe):
+    - handle quoted command-line args (especially filenames with spaces)
+    - finish resizable checkerboard-gradient (sizes 4-128?)
+    - use %.1023s to simplify truncation of title-bar string?
+    - have minimum window width:  oh well
+
+  ---------------------------------------------------------------------------
+
+   Changelog:
+    - 1.01:  initial public release
+    - 1.02:  fixed cut-and-paste error in usage screen (oops...)
+    - 1.03:  modified to allow abbreviated options
+    - 1.04:  removed bogus extra argument from usage fprintf() [Glenn R-P?];
+              fixed command-line parsing bug
+    - 1.10:  enabled "message window"/console (thanks to David Geldreich)
+    - 1.20:  added runtime MMX-enabling/disabling and new -mmx* options
+    - 1.21:  made minor tweak to usage screen to fit within 25-line console
+    - 1.22:  added AMD64/EM64T support (__x86_64__)
+    - 2.00:  dual-licensed (added GNU GPL)
+    - 2.01:  fixed 64-bit typo in readpng2.c
+    - 2.02:  fixed improper display of usage screen on PNG error(s); fixed
+              unexpected-EOF and file-read-error cases
+    - 2.03:  removed runtime MMX-enabling/disabling and obsolete -mmx* options
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-2008 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      The contents of this file are DUAL-LICENSED.  You may modify and/or
+      redistribute this software according to the terms of one of the
+      following two licenses (at your option):
+
+
+      LICENSE 1 ("BSD-like with advertising clause"):
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+
+      LICENSE 2 (GNU GPL v2 or later):
+
+      This program is free software; you can redistribute it and/or modify
+      it under the terms of the GNU General Public License as published by
+      the Free Software Foundation; either version 2 of the License, or
+      (at your option) any later version.
+
+      This program is distributed in the hope that it will be useful,
+      but WITHOUT ANY WARRANTY; without even the implied warranty of
+      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+      GNU General Public License for more details.
+
+      You should have received a copy of the GNU General Public License
+      along with this program; if not, write to the Free Software Foundation,
+      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+  ---------------------------------------------------------------------------*/
+
+#define PROGNAME  "rpng2-win"
+#define LONGNAME  "Progressive PNG Viewer for Windows"
+#define VERSION   "2.02 of 16 March 2008"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <setjmp.h>    /* for jmpbuf declaration in readpng2.h */
+#include <time.h>
+#include <math.h>      /* only for PvdM background code */
+#include <windows.h>
+#ifdef __CYGWIN__
+/* getch replacement. Turns out, we don't really need this,
+ * but leave it here if we ever enable any of the uses of
+ * _getch in the main code
+ */
+#include <unistd.h>
+#include <termio.h>
+#include <sys/ioctl.h>
+int repl_getch( void )
+{
+  char ch;
+  int fd = fileno(stdin);
+  struct termio old_tty, new_tty;
+
+  ioctl(fd, TCGETA, &old_tty);
+  new_tty = old_tty;
+  new_tty.c_lflag &= ~(ICANON | ECHO | ISIG);
+  ioctl(fd, TCSETA, &new_tty);
+  fread(&ch, 1, sizeof(ch), stdin);
+  ioctl(fd, TCSETA, &old_tty);
+
+  return ch;
+}
+#define _getch repl_getch
+#else
+#include <conio.h>     /* only for _getch() */
+#endif
+
+/* all for PvdM background code: */
+#ifndef PI
+#  define PI             3.141592653589793238
+#endif
+#define PI_2             (PI*0.5)
+#define INV_PI_360       (360.0 / PI)
+#define MAX(a,b)         (a>b?a:b)
+#define MIN(a,b)         (a<b?a:b)
+#define CLIP(a,min,max)  MAX(min,MIN((a),max))
+#define ABS(a)           ((a)<0?-(a):(a))
+#define CLIP8P(c)        MAX(0,(MIN((c),255)))   /* 8-bit pos. integer (uch) */
+#define ROUNDF(f)        ((int)(f + 0.5))
+
+#define rgb1_max   bg_freq
+#define rgb1_min   bg_gray
+#define rgb2_max   bg_bsat
+#define rgb2_min   bg_brot
+
+/* #define DEBUG */     /* this enables the Trace() macros */
+
+#include "readpng2.h"   /* typedefs, common macros, readpng2 prototypes */
+
+
+/* could just include png.h, but this macro is the only thing we need
+ * (name and typedefs changed to local versions); note that side effects
+ * only happen with alpha (which could easily be avoided with
+ * "ush acopy = (alpha);") */
+
+#define alpha_composite(composite, fg, alpha, bg) {               \
+    ush temp = ((ush)(fg)*(ush)(alpha) +                          \
+                (ush)(bg)*(ush)(255 - (ush)(alpha)) + (ush)128);  \
+    (composite) = (uch)((temp + (temp >> 8)) >> 8);               \
+}
+
+
+#define INBUFSIZE 4096   /* with pseudo-timing on (1 sec delay/block), this
+                          *  block size corresponds roughly to a download
+                          *  speed 10% faster than theoretical 33.6K maximum
+                          *  (assuming 8 data bits, 1 stop bit and no other
+                          *  overhead) */
+
+/* local prototypes */
+static void       rpng2_win_init(void);
+static int        rpng2_win_create_window(void);
+static int        rpng2_win_load_bg_image(void);
+static void       rpng2_win_display_row(ulg row);
+static void       rpng2_win_finish_display(void);
+static void       rpng2_win_cleanup(void);
+LRESULT CALLBACK  rpng2_win_wndproc(HWND, UINT, WPARAM, LPARAM);
+
+
+static char titlebar[1024];
+static char *progname = PROGNAME;
+static char *appname = LONGNAME;
+static char *filename;
+static FILE *infile;
+
+static mainprog_info rpng2_info;
+
+static uch inbuf[INBUFSIZE];
+static int incount;
+
+static int pat = 6;         /* must be less than num_bgpat */
+static int bg_image = 0;
+static int bgscale = 16;
+static ulg bg_rowbytes;
+static uch *bg_data;
+
+static struct rgb_color {
+    uch r, g, b;
+} rgb[] = {
+    {  0,   0,   0},    /*  0:  black */
+    {255, 255, 255},    /*  1:  white */
+    {173, 132,  57},    /*  2:  tan */
+    { 64, 132,   0},    /*  3:  medium green */
+    {189, 117,   1},    /*  4:  gold */
+    {253, 249,   1},    /*  5:  yellow */
+    {  0,   0, 255},    /*  6:  blue */
+    {  0,   0, 120},    /*  7:  medium blue */
+    {255,   0, 255},    /*  8:  magenta */
+    { 64,   0,  64},    /*  9:  dark magenta */
+    {255,   0,   0},    /* 10:  red */
+    { 64,   0,   0},    /* 11:  dark red */
+    {255, 127,   0},    /* 12:  orange */
+    {192,  96,   0},    /* 13:  darker orange */
+    { 24,  60,   0},    /* 14:  dark green-yellow */
+    { 85, 125, 200}     /* 15:  ice blue */
+};
+/* not used for now, but should be for error-checking:
+static int num_rgb = sizeof(rgb) / sizeof(struct rgb_color);
+ */
+
+/*
+    This whole struct is a fairly cheesy way to keep the number of
+    command-line options to a minimum.  The radial-waves background
+    type is a particularly poor fit to the integer elements of the
+    struct...but a few macros and a little fixed-point math will do
+    wonders for ya.
+
+    type bits:
+       F E D C B A 9 8 7 6 5 4 3 2 1 0
+                             | | | | |
+                             | | +-+-+-- 0 = sharp-edged checkerboard
+                             | |         1 = soft diamonds
+                             | |         2 = radial waves
+                             | |       3-7 = undefined
+                             | +-- gradient #2 inverted?
+                             +-- alternating columns inverted?
+ */
+static struct background_pattern {
+    ush type;
+    int rgb1_max, rgb1_min;     /* or bg_freq, bg_gray */
+    int rgb2_max, rgb2_min;     /* or bg_bsat, bg_brot (both scaled by 10)*/
+} bg[] = {
+    {0+8,   2,0,  1,15},        /* checkered:  tan/black vs. white/ice blue */
+    {0+24,  2,0,  1,0},         /* checkered:  tan/black vs. white/black */
+    {0+8,   4,5,  0,2},         /* checkered:  gold/yellow vs. black/tan */
+    {0+8,   4,5,  0,6},         /* checkered:  gold/yellow vs. black/blue */
+    {0,     7,0,  8,9},         /* checkered:  deep blue/black vs. magenta */
+    {0+8,  13,0,  5,14},        /* checkered:  orange/black vs. yellow */
+    {0+8,  12,0, 10,11},        /* checkered:  orange/black vs. red */
+    {1,     7,0,  8,0},         /* diamonds:  deep blue/black vs. magenta */
+    {1,    12,0, 11,0},         /* diamonds:  orange vs. dark red */
+    {1,    10,0,  7,0},         /* diamonds:  red vs. medium blue */
+    {1,     4,0,  5,0},         /* diamonds:  gold vs. yellow */
+    {1,     3,0,  0,0},         /* diamonds:  medium green vs. black */
+    {2,    16, 100,  20,   0},  /* radial:  ~hard radial color-beams */
+    {2,    18, 100,  10,   2},  /* radial:  soft, curved radial color-beams */
+    {2,    16, 256, 100, 250},  /* radial:  very tight spiral */
+    {2, 10000, 256,  11,   0}   /* radial:  dipole-moire' (almost fractal) */
+};
+static int num_bgpat = sizeof(bg) / sizeof(struct background_pattern);
+
+
+/* Windows-specific global variables (could go in struct, but messy...) */
+static ulg wimage_rowbytes;
+static uch *dib;
+static uch *wimage_data;
+static BITMAPINFOHEADER *bmih;
+
+static HWND global_hwnd;
+static HINSTANCE global_hInst;
+static int global_showmode;
+
+
+
+
+int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, PSTR cmd, int showmode)
+{
+    char *args[1024];                 /* arbitrary limit, but should suffice */
+    char **argv = args;
+    char *p, *q, *bgstr = NULL;
+    int argc = 0;
+    int rc, alen, flen;
+    int error = 0;
+    int timing = FALSE;
+    int have_bg = FALSE;
+    double LUT_exponent;              /* just the lookup table */
+    double CRT_exponent = 2.2;        /* just the monitor */
+    double default_display_exponent;  /* whole display system */
+    MSG msg;
+
+
+    /* First initialize a few things, just to be sure--memset takes care of
+     * default background color (black), booleans (FALSE), pointers (NULL),
+     * etc. */
+
+    global_hInst = hInst;
+    global_showmode = showmode;
+    filename = (char *)NULL;
+    memset(&rpng2_info, 0, sizeof(mainprog_info));
+
+#ifndef __CYGWIN__
+    /* Next reenable console output, which normally goes to the bit bucket
+     * for windowed apps.  Closing the console window will terminate the
+     * app.  Thanks to David.Geldreich@realviz.com for supplying the magical
+     * incantation. */
+
+    AllocConsole();
+    freopen("CONOUT$", "a", stderr);
+    freopen("CONOUT$", "a", stdout);
+#endif
+
+    /* Set the default value for our display-system exponent, i.e., the
+     * product of the CRT exponent and the exponent corresponding to
+     * the frame-buffer's lookup table (LUT), if any.  This is not an
+     * exhaustive list of LUT values (e.g., OpenStep has a lot of weird
+     * ones), but it should cover 99% of the current possibilities.  And
+     * yes, these ifdefs are completely wasted in a Windows program... */
+
+#if defined(NeXT)
+    /* third-party utilities can modify the default LUT exponent */
+    LUT_exponent = 1.0 / 2.2;
+    /*
+    if (some_next_function_that_returns_gamma(&next_gamma))
+        LUT_exponent = 1.0 / next_gamma;
+     */
+#elif defined(sgi)
+    LUT_exponent = 1.0 / 1.7;
+    /* there doesn't seem to be any documented function to
+     * get the "gamma" value, so we do it the hard way */
+    infile = fopen("/etc/config/system.glGammaVal", "r");
+    if (infile) {
+        double sgi_gamma;
+
+        fgets(tmpline, 80, infile);
+        fclose(infile);
+        sgi_gamma = atof(tmpline);
+        if (sgi_gamma > 0.0)
+            LUT_exponent = 1.0 / sgi_gamma;
+    }
+#elif defined(Macintosh)
+    LUT_exponent = 1.8 / 2.61;
+    /*
+    if (some_mac_function_that_returns_gamma(&mac_gamma))
+        LUT_exponent = mac_gamma / 2.61;
+     */
+#else
+    LUT_exponent = 1.0;   /* assume no LUT:  most PCs */
+#endif
+
+    /* the defaults above give 1.0, 1.3, 1.5 and 2.2, respectively: */
+    default_display_exponent = LUT_exponent * CRT_exponent;
+
+
+    /* If the user has set the SCREEN_GAMMA environment variable as suggested
+     * (somewhat imprecisely) in the libpng documentation, use that; otherwise
+     * use the default value we just calculated.  Either way, the user may
+     * override this via a command-line option. */
+
+    if ((p = getenv("SCREEN_GAMMA")) != NULL)
+        rpng2_info.display_exponent = atof(p);
+    else
+        rpng2_info.display_exponent = default_display_exponent;
+
+
+    /* Windows really hates command lines, so we have to set up our own argv.
+     * Note that we do NOT bother with quoted arguments here, so don't use
+     * filenames with spaces in 'em! */
+
+    argv[argc++] = PROGNAME;
+    p = cmd;
+    for (;;) {
+        if (*p == ' ')
+            while (*++p == ' ')
+                ;
+        /* now p points at the first non-space after some spaces */
+        if (*p == '\0')
+            break;    /* nothing after the spaces:  done */
+        argv[argc++] = q = p;
+        while (*q && *q != ' ')
+            ++q;
+        /* now q points at a space or the end of the string */
+        if (*q == '\0')
+            break;    /* last argv already terminated; quit */
+        *q = '\0';    /* change space to terminator */
+        p = q + 1;
+    }
+    argv[argc] = NULL;   /* terminate the argv array itself */
+
+
+    /* Now parse the command line for options and the PNG filename. */
+
+    while (*++argv && !error) {
+        if (!strncmp(*argv, "-gamma", 2)) {
+            if (!*++argv)
+                ++error;
+            else {
+                rpng2_info.display_exponent = atof(*argv);
+                if (rpng2_info.display_exponent <= 0.0)
+                    ++error;
+            }
+        } else if (!strncmp(*argv, "-bgcolor", 4)) {
+            if (!*++argv)
+                ++error;
+            else {
+                bgstr = *argv;
+                if (strlen(bgstr) != 7 || bgstr[0] != '#')
+                    ++error;
+                else {
+                    have_bg = TRUE;
+                    bg_image = FALSE;
+                }
+            }
+        } else if (!strncmp(*argv, "-bgpat", 4)) {
+            if (!*++argv)
+                ++error;
+            else {
+                pat = atoi(*argv) - 1;
+                if (pat < 0 || pat >= num_bgpat)
+                    ++error;
+                else {
+                    bg_image = TRUE;
+                    have_bg = FALSE;
+                }
+            }
+        } else if (!strncmp(*argv, "-timing", 2)) {
+            timing = TRUE;
+        } else {
+            if (**argv != '-') {
+                filename = *argv;
+                if (argv[1])   /* shouldn't be any more args after filename */
+                    ++error;
+            } else
+                ++error;   /* not expecting any other options */
+        }
+    }
+
+    if (!filename)
+        ++error;
+
+
+    /* print usage screen if any errors up to this point */
+
+    if (error) {
+#ifndef __CYGWIN__
+        int ch;
+#endif
+
+        fprintf(stderr, "\n%s %s:  %s\n\n", PROGNAME, VERSION, appname);
+        readpng2_version_info();
+        fprintf(stderr, "\n"
+          "Usage:  %s [-gamma exp] [-bgcolor bg | -bgpat pat] [-timing]\n"
+          "        %*s file.png\n\n"
+          "    exp \ttransfer-function exponent (``gamma'') of the display\n"
+          "\t\t  system in floating-point format (e.g., ``%.1f''); equal\n"
+          "\t\t  to the product of the lookup-table exponent (varies)\n"
+          "\t\t  and the CRT exponent (usually 2.2); must be positive\n"
+          "    bg  \tdesired background color in 7-character hex RGB format\n"
+          "\t\t  (e.g., ``#ff7700'' for orange:  same as HTML colors);\n"
+          "\t\t  used with transparent images; overrides -bgpat option\n"
+          "    pat \tdesired background pattern number (1-%d); used with\n"
+          "\t\t  transparent images; overrides -bgcolor option\n"
+          "    -timing\tenables delay for every block read, to simulate modem\n"
+          "\t\t  download of image (~36 Kbps)\n"
+          "\nPress Q, Esc or mouse button 1 after image is displayed to quit.\n"
+#ifndef __CYGWIN__
+          "Press Q or Esc to quit this usage screen. ",
+#else
+          ,
+#endif
+          PROGNAME,
+#if (defined(__i386__) || defined(_M_IX86) || defined(__x86_64__)) && \
+    !(defined(__CYGWIN__) || defined(__MINGW32__))
+          (int)strlen(PROGNAME), " ",
+#endif
+          (int)strlen(PROGNAME), " ", default_display_exponent, num_bgpat);
+        fflush(stderr);
+#ifndef __CYGWIN__
+        do
+            ch = _getch();
+        while (ch != 'q' && ch != 'Q' && ch != 0x1B);
+#endif
+        exit(1);
+    }
+
+
+    if (!(infile = fopen(filename, "rb"))) {
+        fprintf(stderr, PROGNAME ":  can't open PNG file [%s]\n", filename);
+        ++error;
+    } else {
+        incount = fread(inbuf, 1, INBUFSIZE, infile);
+        if (incount < 8 || !readpng2_check_sig(inbuf, 8)) {
+            fprintf(stderr, PROGNAME
+              ":  [%s] is not a PNG file: incorrect signature\n",
+              filename);
+            ++error;
+        } else if ((rc = readpng2_init(&rpng2_info)) != 0) {
+            switch (rc) {
+                case 2:
+                    fprintf(stderr, PROGNAME
+                      ":  [%s] has bad IHDR (libpng longjmp)\n", filename);
+                    break;
+                case 4:
+                    fprintf(stderr, PROGNAME ":  insufficient memory\n");
+                    break;
+                default:
+                    fprintf(stderr, PROGNAME
+                      ":  unknown readpng2_init() error\n");
+                    break;
+            }
+            ++error;
+        }
+        if (error)
+            fclose(infile);
+    }
+
+
+    if (error) {
+#ifndef __CYGWIN__
+        int ch;
+#endif
+
+        fprintf(stderr, PROGNAME ":  aborting.\n");
+#ifndef __CYGWIN__
+        do
+            ch = _getch();
+        while (ch != 'q' && ch != 'Q' && ch != 0x1B);
+#endif
+        exit(2);
+    } else {
+        fprintf(stderr, "\n%s %s:  %s\n", PROGNAME, VERSION, appname);
+#ifndef __CYGWIN__
+        fprintf(stderr,
+          "\n   [console window:  closing this window will terminate %s]\n\n",
+          PROGNAME);
+#endif
+        fflush(stderr);
+    }
+
+
+    /* set the title-bar string, but make sure buffer doesn't overflow */
+
+    alen = strlen(appname);
+    flen = strlen(filename);
+    if (alen + flen + 3 > 1023)
+        sprintf(titlebar, "%s:  ...%s", appname, filename+(alen+flen+6-1023));
+    else
+        sprintf(titlebar, "%s:  %s", appname, filename);
+
+
+    /* set some final rpng2_info variables before entering main data loop */
+
+    if (have_bg) {
+        unsigned r, g, b;   /* this approach quiets compiler warnings */
+
+        sscanf(bgstr+1, "%2x%2x%2x", &r, &g, &b);
+        rpng2_info.bg_red   = (uch)r;
+        rpng2_info.bg_green = (uch)g;
+        rpng2_info.bg_blue  = (uch)b;
+    } else
+        rpng2_info.need_bgcolor = TRUE;
+
+    rpng2_info.state = kPreInit;
+    rpng2_info.mainprog_init = rpng2_win_init;
+    rpng2_info.mainprog_display_row = rpng2_win_display_row;
+    rpng2_info.mainprog_finish_display = rpng2_win_finish_display;
+
+
+    /* OK, this is the fun part:  call readpng2_decode_data() at the start of
+     * the loop to deal with our first buffer of data (read in above to verify
+     * that the file is a PNG image), then loop through the file and continue
+     * calling the same routine to handle each chunk of data.  It in turn
+     * passes the data to libpng, which will invoke one or more of our call-
+     * backs as decoded data become available.  We optionally call Sleep() for
+     * one second per iteration to simulate downloading the image via an analog
+     * modem. */
+
+    for (;;) {
+        Trace((stderr, "about to call readpng2_decode_data()\n"))
+        if (readpng2_decode_data(&rpng2_info, inbuf, incount))
+            ++error;
+        Trace((stderr, "done with readpng2_decode_data()\n"))
+
+        if (error || incount != INBUFSIZE || rpng2_info.state == kDone) {
+            if (rpng2_info.state == kDone) {
+                Trace((stderr, "done decoding PNG image\n"))
+            } else if (ferror(infile)) {
+                fprintf(stderr, PROGNAME
+                  ":  error while reading PNG image file\n");
+                exit(3);
+            } else if (feof(infile)) {
+                fprintf(stderr, PROGNAME ":  end of file reached "
+                  "(unexpectedly) while reading PNG image file\n");
+                exit(3);
+            } else /* if (error) */ {
+                /* will print error message below */
+            }
+            break;
+        }
+
+        if (timing)
+            Sleep(1000L);
+
+        incount = fread(inbuf, 1, INBUFSIZE, infile);
+    }
+
+
+    /* clean up PNG stuff and report any decoding errors */
+
+    fclose(infile);
+    Trace((stderr, "about to call readpng2_cleanup()\n"))
+    readpng2_cleanup(&rpng2_info);
+
+    if (error) {
+        fprintf(stderr, PROGNAME ":  libpng error while decoding PNG image\n");
+        exit(3);
+    }
+
+
+    /* wait for the user to tell us when to quit */
+
+    while (GetMessage(&msg, NULL, 0, 0)) {
+        TranslateMessage(&msg);
+        DispatchMessage(&msg);
+    }
+
+
+    /* we're done:  clean up all image and Windows resources and go away */
+
+    Trace((stderr, "about to call rpng2_win_cleanup()\n"))
+    rpng2_win_cleanup();
+
+    return msg.wParam;
+}
+
+
+
+
+
+/* this function is called by readpng2_info_callback() in readpng2.c, which
+ * in turn is called by libpng after all of the pre-IDAT chunks have been
+ * read and processed--i.e., we now have enough info to finish initializing */
+
+static void rpng2_win_init()
+{
+    ulg i;
+    ulg rowbytes = rpng2_info.rowbytes;
+
+    Trace((stderr, "beginning rpng2_win_init()\n"))
+    Trace((stderr, "  rowbytes = %d\n", rpng2_info.rowbytes))
+    Trace((stderr, "  width  = %ld\n", rpng2_info.width))
+    Trace((stderr, "  height = %ld\n", rpng2_info.height))
+
+    rpng2_info.image_data = (uch *)malloc(rowbytes * rpng2_info.height);
+    if (!rpng2_info.image_data) {
+        readpng2_cleanup(&rpng2_info);
+        return;
+    }
+
+    rpng2_info.row_pointers = (uch **)malloc(rpng2_info.height * sizeof(uch *));
+    if (!rpng2_info.row_pointers) {
+        free(rpng2_info.image_data);
+        rpng2_info.image_data = NULL;
+        readpng2_cleanup(&rpng2_info);
+        return;
+    }
+
+    for (i = 0;  i < rpng2_info.height;  ++i)
+        rpng2_info.row_pointers[i] = rpng2_info.image_data + i*rowbytes;
+
+/*---------------------------------------------------------------------------
+    Do the basic Windows initialization stuff, make the window, and fill it
+    with the user-specified, file-specified or default background color.
+  ---------------------------------------------------------------------------*/
+
+    if (rpng2_win_create_window()) {
+        readpng2_cleanup(&rpng2_info);
+        return;
+    }
+
+    rpng2_info.state = kWindowInit;
+}
+
+
+
+
+
+static int rpng2_win_create_window()
+{
+    uch bg_red   = rpng2_info.bg_red;
+    uch bg_green = rpng2_info.bg_green;
+    uch bg_blue  = rpng2_info.bg_blue;
+    uch *dest;
+    int extra_width, extra_height;
+    ulg i, j;
+    WNDCLASSEX wndclass;
+    RECT rect;
+
+
+/*---------------------------------------------------------------------------
+    Allocate memory for the display-specific version of the image (round up
+    to multiple of 4 for Windows DIB).
+  ---------------------------------------------------------------------------*/
+
+    wimage_rowbytes = ((3*rpng2_info.width + 3L) >> 2) << 2;
+
+    if (!(dib = (uch *)malloc(sizeof(BITMAPINFOHEADER) +
+                              wimage_rowbytes*rpng2_info.height)))
+    {
+        return 4;   /* fail */
+    }
+
+/*---------------------------------------------------------------------------
+    Initialize the DIB.  Negative height means to use top-down BMP ordering
+    (must be uncompressed, but that's what we want).  Bit count of 1, 4 or 8
+    implies a colormap of RGBX quads, but 24-bit BMPs just use B,G,R values
+    directly => wimage_data begins immediately after BMP header.
+  ---------------------------------------------------------------------------*/
+
+    memset(dib, 0, sizeof(BITMAPINFOHEADER));
+    bmih = (BITMAPINFOHEADER *)dib;
+    bmih->biSize = sizeof(BITMAPINFOHEADER);
+    bmih->biWidth = rpng2_info.width;
+    bmih->biHeight = -((long)rpng2_info.height);
+    bmih->biPlanes = 1;
+    bmih->biBitCount = 24;
+    bmih->biCompression = 0;
+    wimage_data = dib + sizeof(BITMAPINFOHEADER);
+
+/*---------------------------------------------------------------------------
+    Fill window with the specified background color (default is black), but
+    defer loading faked "background image" until window is displayed (may be
+    slow to compute).  Data are in BGR order.
+  ---------------------------------------------------------------------------*/
+
+    if (bg_image) {   /* just fill with black for now */
+        memset(wimage_data, 0, wimage_rowbytes*rpng2_info.height);
+    } else {
+        for (j = 0;  j < rpng2_info.height;  ++j) {
+            dest = wimage_data + j*wimage_rowbytes;
+            for (i = rpng2_info.width;  i > 0;  --i) {
+                *dest++ = bg_blue;
+                *dest++ = bg_green;
+                *dest++ = bg_red;
+            }
+        }
+    }
+
+/*---------------------------------------------------------------------------
+    Set the window parameters.
+  ---------------------------------------------------------------------------*/
+
+    memset(&wndclass, 0, sizeof(wndclass));
+
+    wndclass.cbSize = sizeof(wndclass);
+    wndclass.style = CS_HREDRAW | CS_VREDRAW;
+    wndclass.lpfnWndProc = rpng2_win_wndproc;
+    wndclass.hInstance = global_hInst;
+    wndclass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
+    wndclass.hCursor = LoadCursor(NULL, IDC_ARROW);
+    wndclass.hbrBackground = (HBRUSH)GetStockObject(DKGRAY_BRUSH);
+    wndclass.lpszMenuName = NULL;
+    wndclass.lpszClassName = progname;
+    wndclass.hIconSm = LoadIcon(NULL, IDI_APPLICATION);
+
+    RegisterClassEx(&wndclass);
+
+/*---------------------------------------------------------------------------
+    Finally, create the window.
+  ---------------------------------------------------------------------------*/
+
+    extra_width  = 2*(GetSystemMetrics(SM_CXBORDER) +
+                      GetSystemMetrics(SM_CXDLGFRAME));
+    extra_height = 2*(GetSystemMetrics(SM_CYBORDER) +
+                      GetSystemMetrics(SM_CYDLGFRAME)) +
+                      GetSystemMetrics(SM_CYCAPTION);
+
+    global_hwnd = CreateWindow(progname, titlebar, WS_OVERLAPPEDWINDOW,
+      CW_USEDEFAULT, CW_USEDEFAULT, rpng2_info.width+extra_width,
+      rpng2_info.height+extra_height, NULL, NULL, global_hInst, NULL);
+
+    ShowWindow(global_hwnd, global_showmode);
+    UpdateWindow(global_hwnd);
+
+/*---------------------------------------------------------------------------
+    Now compute the background image and display it.  If it fails (memory
+    allocation), revert to a plain background color.
+  ---------------------------------------------------------------------------*/
+
+    if (bg_image) {
+        static const char *msg = "Computing background image...";
+        int x, y, len = strlen(msg);
+        HDC hdc = GetDC(global_hwnd);
+        TEXTMETRIC tm;
+
+        GetTextMetrics(hdc, &tm);
+        x = (rpng2_info.width - len*tm.tmAveCharWidth)/2;
+        y = (rpng2_info.height - tm.tmHeight)/2;
+        SetBkMode(hdc, TRANSPARENT);
+        SetTextColor(hdc, GetSysColor(COLOR_HIGHLIGHTTEXT));
+        /* this can still begin out of bounds even if x is positive (???): */
+        TextOut(hdc, ((x < 0)? 0 : x), ((y < 0)? 0 : y), msg, len);
+        ReleaseDC(global_hwnd, hdc);
+
+        rpng2_win_load_bg_image();   /* resets bg_image if fails */
+    }
+
+    if (!bg_image) {
+        for (j = 0;  j < rpng2_info.height;  ++j) {
+            dest = wimage_data + j*wimage_rowbytes;
+            for (i = rpng2_info.width;  i > 0;  --i) {
+                *dest++ = bg_blue;
+                *dest++ = bg_green;
+                *dest++ = bg_red;
+            }
+        }
+    }
+
+    rect.left = 0L;
+    rect.top = 0L;
+    rect.right = (LONG)rpng2_info.width;       /* possibly off by one? */
+    rect.bottom = (LONG)rpng2_info.height;     /* possibly off by one? */
+    InvalidateRect(global_hwnd, &rect, FALSE);
+    UpdateWindow(global_hwnd);                 /* similar to XFlush() */
+
+    return 0;
+
+} /* end function rpng2_win_create_window() */
+
+
+
+
+
+static int rpng2_win_load_bg_image()
+{
+    uch *src, *dest;
+    uch r1, r2, g1, g2, b1, b2;
+    uch r1_inv, r2_inv, g1_inv, g2_inv, b1_inv, b2_inv;
+    int k, hmax, max;
+    int xidx, yidx, yidx_max = (bgscale-1);
+    int even_odd_vert, even_odd_horiz, even_odd;
+    int invert_gradient2 = (bg[pat].type & 0x08);
+    int invert_column;
+    ulg i, row;
+
+/*---------------------------------------------------------------------------
+    Allocate buffer for fake background image to be used with transparent
+    images; if this fails, revert to plain background color.
+  ---------------------------------------------------------------------------*/
+
+    bg_rowbytes = 3 * rpng2_info.width;
+    bg_data = (uch *)malloc(bg_rowbytes * rpng2_info.height);
+    if (!bg_data) {
+        fprintf(stderr, PROGNAME
+          ":  unable to allocate memory for background image\n");
+        bg_image = 0;
+        return 1;
+    }
+
+/*---------------------------------------------------------------------------
+    Vertical gradients (ramps) in NxN squares, alternating direction and
+    colors (N == bgscale).
+  ---------------------------------------------------------------------------*/
+
+    if ((bg[pat].type & 0x07) == 0) {
+        uch r1_min  = rgb[bg[pat].rgb1_min].r;
+        uch g1_min  = rgb[bg[pat].rgb1_min].g;
+        uch b1_min  = rgb[bg[pat].rgb1_min].b;
+        uch r2_min  = rgb[bg[pat].rgb2_min].r;
+        uch g2_min  = rgb[bg[pat].rgb2_min].g;
+        uch b2_min  = rgb[bg[pat].rgb2_min].b;
+        int r1_diff = rgb[bg[pat].rgb1_max].r - r1_min;
+        int g1_diff = rgb[bg[pat].rgb1_max].g - g1_min;
+        int b1_diff = rgb[bg[pat].rgb1_max].b - b1_min;
+        int r2_diff = rgb[bg[pat].rgb2_max].r - r2_min;
+        int g2_diff = rgb[bg[pat].rgb2_max].g - g2_min;
+        int b2_diff = rgb[bg[pat].rgb2_max].b - b2_min;
+
+        for (row = 0;  row < rpng2_info.height;  ++row) {
+            yidx = row % bgscale;
+            even_odd_vert = (row / bgscale) & 1;
+
+            r1 = r1_min + (r1_diff * yidx) / yidx_max;
+            g1 = g1_min + (g1_diff * yidx) / yidx_max;
+            b1 = b1_min + (b1_diff * yidx) / yidx_max;
+            r1_inv = r1_min + (r1_diff * (yidx_max-yidx)) / yidx_max;
+            g1_inv = g1_min + (g1_diff * (yidx_max-yidx)) / yidx_max;
+            b1_inv = b1_min + (b1_diff * (yidx_max-yidx)) / yidx_max;
+
+            r2 = r2_min + (r2_diff * yidx) / yidx_max;
+            g2 = g2_min + (g2_diff * yidx) / yidx_max;
+            b2 = b2_min + (b2_diff * yidx) / yidx_max;
+            r2_inv = r2_min + (r2_diff * (yidx_max-yidx)) / yidx_max;
+            g2_inv = g2_min + (g2_diff * (yidx_max-yidx)) / yidx_max;
+            b2_inv = b2_min + (b2_diff * (yidx_max-yidx)) / yidx_max;
+
+            dest = bg_data + row*bg_rowbytes;
+            for (i = 0;  i < rpng2_info.width;  ++i) {
+                even_odd_horiz = (i / bgscale) & 1;
+                even_odd = even_odd_vert ^ even_odd_horiz;
+                invert_column =
+                  (even_odd_horiz && (bg[pat].type & 0x10));
+                if (even_odd == 0) {         /* gradient #1 */
+                    if (invert_column) {
+                        *dest++ = r1_inv;
+                        *dest++ = g1_inv;
+                        *dest++ = b1_inv;
+                    } else {
+                        *dest++ = r1;
+                        *dest++ = g1;
+                        *dest++ = b1;
+                    }
+                } else {                     /* gradient #2 */
+                    if ((invert_column && invert_gradient2) ||
+                        (!invert_column && !invert_gradient2))
+                    {
+                        *dest++ = r2;        /* not inverted or */
+                        *dest++ = g2;        /*  doubly inverted */
+                        *dest++ = b2;
+                    } else {
+                        *dest++ = r2_inv;
+                        *dest++ = g2_inv;    /* singly inverted */
+                        *dest++ = b2_inv;
+                    }
+                }
+            }
+        }
+
+/*---------------------------------------------------------------------------
+    Soft gradient-diamonds with scale = bgscale.  Code contributed by Adam
+    M. Costello.
+  ---------------------------------------------------------------------------*/
+
+    } else if ((bg[pat].type & 0x07) == 1) {
+
+        hmax = (bgscale-1)/2;   /* half the max weight of a color */
+        max = 2*hmax;           /* the max weight of a color */
+
+        r1 = rgb[bg[pat].rgb1_max].r;
+        g1 = rgb[bg[pat].rgb1_max].g;
+        b1 = rgb[bg[pat].rgb1_max].b;
+        r2 = rgb[bg[pat].rgb2_max].r;
+        g2 = rgb[bg[pat].rgb2_max].g;
+        b2 = rgb[bg[pat].rgb2_max].b;
+
+        for (row = 0;  row < rpng2_info.height;  ++row) {
+            yidx = row % bgscale;
+            if (yidx > hmax)
+                yidx = bgscale-1 - yidx;
+            dest = bg_data + row*bg_rowbytes;
+            for (i = 0;  i < rpng2_info.width;  ++i) {
+                xidx = i % bgscale;
+                if (xidx > hmax)
+                    xidx = bgscale-1 - xidx;
+                k = xidx + yidx;
+                *dest++ = (k*r1 + (max-k)*r2) / max;
+                *dest++ = (k*g1 + (max-k)*g2) / max;
+                *dest++ = (k*b1 + (max-k)*b2) / max;
+            }
+        }
+
+/*---------------------------------------------------------------------------
+    Radial "starburst" with azimuthal sinusoids; [eventually number of sinu-
+    soids will equal bgscale?].  This one is slow but very cool.  Code con-
+    tributed by Pieter S. van der Meulen (originally in Smalltalk).
+  ---------------------------------------------------------------------------*/
+
+    } else if ((bg[pat].type & 0x07) == 2) {
+        uch ch;
+        int ii, x, y, hw, hh, grayspot;
+        double freq, rotate, saturate, gray, intensity;
+        double angle=0.0, aoffset=0.0, maxDist, dist;
+        double red=0.0, green=0.0, blue=0.0, hue, s, v, f, p, q, t;
+
+        fprintf(stderr, "%s:  computing radial background...",
+          PROGNAME);
+        fflush(stderr);
+
+        hh = rpng2_info.height / 2;
+        hw = rpng2_info.width / 2;
+
+        /* variables for radial waves:
+         *   aoffset:  number of degrees to rotate hue [CURRENTLY NOT USED]
+         *   freq:  number of color beams originating from the center
+         *   grayspot:  size of the graying center area (anti-alias)
+         *   rotate:  rotation of the beams as a function of radius
+         *   saturate:  saturation of beams' shape azimuthally
+         */
+        angle = CLIP(angle, 0.0, 360.0);
+        grayspot = CLIP(bg[pat].bg_gray, 1, (hh + hw));
+        freq = MAX((double)bg[pat].bg_freq, 0.0);
+        saturate = (double)bg[pat].bg_bsat * 0.1;
+        rotate = (double)bg[pat].bg_brot * 0.1;
+        gray = 0.0;
+        intensity = 0.0;
+        maxDist = (double)((hw*hw) + (hh*hh));
+
+        for (row = 0;  row < rpng2_info.height;  ++row) {
+            y = row - hh;
+            dest = bg_data + row*bg_rowbytes;
+            for (i = 0;  i < rpng2_info.width;  ++i) {
+                x = i - hw;
+                angle = (x == 0)? PI_2 : atan((double)y / (double)x);
+                gray = (double)MAX(ABS(y), ABS(x)) / grayspot;
+                gray = MIN(1.0, gray);
+                dist = (double)((x*x) + (y*y)) / maxDist;
+                intensity = cos((angle+(rotate*dist*PI)) * freq) *
+                  gray * saturate;
+                intensity = (MAX(MIN(intensity,1.0),-1.0) + 1.0) * 0.5;
+                hue = (angle + PI) * INV_PI_360 + aoffset;
+                s = gray * ((double)(ABS(x)+ABS(y)) / (double)(hw + hh));
+                s = MIN(MAX(s,0.0), 1.0);
+                v = MIN(MAX(intensity,0.0), 1.0);
+
+                if (s == 0.0) {
+                    ch = (uch)(v * 255.0);
+                    *dest++ = ch;
+                    *dest++ = ch;
+                    *dest++ = ch;
+                } else {
+                    if ((hue < 0.0) || (hue >= 360.0))
+                        hue -= (((int)(hue / 360.0)) * 360.0);
+                    hue /= 60.0;
+                    ii = (int)hue;
+                    f = hue - (double)ii;
+                    p = (1.0 - s) * v;
+                    q = (1.0 - (s * f)) * v;
+                    t = (1.0 - (s * (1.0 - f))) * v;
+                    if      (ii == 0) { red = v; green = t; blue = p; }
+                    else if (ii == 1) { red = q; green = v; blue = p; }
+                    else if (ii == 2) { red = p; green = v; blue = t; }
+                    else if (ii == 3) { red = p; green = q; blue = v; }
+                    else if (ii == 4) { red = t; green = p; blue = v; }
+                    else if (ii == 5) { red = v; green = p; blue = q; }
+                    *dest++ = (uch)(red * 255.0);
+                    *dest++ = (uch)(green * 255.0);
+                    *dest++ = (uch)(blue * 255.0);
+                }
+            }
+        }
+        fprintf(stderr, "done.\n");
+        fflush(stderr);
+    }
+
+/*---------------------------------------------------------------------------
+    Blast background image to display buffer before beginning PNG decode;
+    calling function will handle invalidation and UpdateWindow() call.
+  ---------------------------------------------------------------------------*/
+
+    for (row = 0;  row < rpng2_info.height;  ++row) {
+        src = bg_data + row*bg_rowbytes;
+        dest = wimage_data + row*wimage_rowbytes;
+        for (i = rpng2_info.width;  i > 0;  --i) {
+            r1 = *src++;
+            g1 = *src++;
+            b1 = *src++;
+            *dest++ = b1;
+            *dest++ = g1;   /* note reverse order */
+            *dest++ = r1;
+        }
+    }
+
+    return 0;
+
+} /* end function rpng2_win_load_bg_image() */
+
+
+
+
+
+static void rpng2_win_display_row(ulg row)
+{
+    uch bg_red   = rpng2_info.bg_red;
+    uch bg_green = rpng2_info.bg_green;
+    uch bg_blue  = rpng2_info.bg_blue;
+    uch *src, *src2=NULL, *dest;
+    uch r, g, b, a;
+    ulg i;
+    static int rows=0;
+    static ulg firstrow;
+
+/*---------------------------------------------------------------------------
+    rows and firstrow simply track how many rows (and which ones) have not
+    yet been displayed; alternatively, we could call InvalidateRect() for
+    every row and not bother with the records-keeping.
+  ---------------------------------------------------------------------------*/
+
+    Trace((stderr, "beginning rpng2_win_display_row()\n"))
+
+    if (rows == 0)
+        firstrow = row;   /* first row not yet displayed */
+
+    ++rows;   /* count of rows received but not yet displayed */
+
+/*---------------------------------------------------------------------------
+    Aside from the use of the rpng2_info struct and the lack of an outer
+    loop (over rows), this routine is identical to rpng_win_display_image()
+    in the non-progressive version of the program.
+  ---------------------------------------------------------------------------*/
+
+    src = rpng2_info.image_data + row*rpng2_info.rowbytes;
+    if (bg_image)
+        src2 = bg_data + row*bg_rowbytes;
+    dest = wimage_data + row*wimage_rowbytes;
+
+    if (rpng2_info.channels == 3) {
+        for (i = rpng2_info.width;  i > 0;  --i) {
+            r = *src++;
+            g = *src++;
+            b = *src++;
+            *dest++ = b;
+            *dest++ = g;   /* note reverse order */
+            *dest++ = r;
+        }
+    } else /* if (rpng2_info.channels == 4) */ {
+        for (i = rpng2_info.width;  i > 0;  --i) {
+            r = *src++;
+            g = *src++;
+            b = *src++;
+            a = *src++;
+            if (bg_image) {
+                bg_red   = *src2++;
+                bg_green = *src2++;
+                bg_blue  = *src2++;
+            }
+            if (a == 255) {
+                *dest++ = b;
+                *dest++ = g;
+                *dest++ = r;
+            } else if (a == 0) {
+                *dest++ = bg_blue;
+                *dest++ = bg_green;
+                *dest++ = bg_red;
+            } else {
+                /* this macro (copied from png.h) composites the
+                 * foreground and background values and puts the
+                 * result into the first argument; there are no
+                 * side effects with the first argument */
+                alpha_composite(*dest++, b, a, bg_blue);
+                alpha_composite(*dest++, g, a, bg_green);
+                alpha_composite(*dest++, r, a, bg_red);
+            }
+        }
+    }
+
+/*---------------------------------------------------------------------------
+    Display after every 16 rows or when on last row.  (Region may include
+    previously displayed lines due to interlacing--i.e., not contiguous.)
+  ---------------------------------------------------------------------------*/
+
+    if ((rows & 0xf) == 0 || row == rpng2_info.height-1) {
+        RECT rect;
+
+        rect.left = 0L;
+        rect.top = (LONG)firstrow;
+        rect.right = (LONG)rpng2_info.width;       /* possibly off by one? */
+        rect.bottom = (LONG)row + 1L;              /* possibly off by one? */
+        InvalidateRect(global_hwnd, &rect, FALSE);
+        UpdateWindow(global_hwnd);                 /* similar to XFlush() */
+        rows = 0;
+    }
+
+} /* end function rpng2_win_display_row() */
+
+
+
+
+
+static void rpng2_win_finish_display()
+{
+    Trace((stderr, "beginning rpng2_win_finish_display()\n"))
+
+    /* last row has already been displayed by rpng2_win_display_row(), so
+     * we have nothing to do here except set a flag and let the user know
+     * that the image is done */
+
+    rpng2_info.state = kDone;
+    printf(
+#ifndef __CYGWIN__
+      "Done.  Press Q, Esc or mouse button 1 (within image window) to quit.\n"
+#else
+      "Done.  Press mouse button 1 (within image window) to quit.\n"
+#endif
+    );
+    fflush(stdout);
+}
+
+
+
+
+
+static void rpng2_win_cleanup()
+{
+    if (bg_image && bg_data) {
+        free(bg_data);
+        bg_data = NULL;
+    }
+
+    if (rpng2_info.image_data) {
+        free(rpng2_info.image_data);
+        rpng2_info.image_data = NULL;
+    }
+
+    if (rpng2_info.row_pointers) {
+        free(rpng2_info.row_pointers);
+        rpng2_info.row_pointers = NULL;
+    }
+
+    if (dib) {
+        free(dib);
+        dib = NULL;
+    }
+}
+
+
+
+
+
+LRESULT CALLBACK rpng2_win_wndproc(HWND hwnd, UINT iMsg, WPARAM wP, LPARAM lP)
+{
+    HDC         hdc;
+    PAINTSTRUCT ps;
+    int rc;
+
+    switch (iMsg) {
+        case WM_CREATE:
+            /* one-time processing here, if any */
+            return 0;
+
+        case WM_PAINT:
+            hdc = BeginPaint(hwnd, &ps);
+            rc = StretchDIBits(hdc, 0, 0, rpng2_info.width, rpng2_info.height,
+                                    0, 0, rpng2_info.width, rpng2_info.height,
+                                    wimage_data, (BITMAPINFO *)bmih,
+                                    0, SRCCOPY);
+            EndPaint(hwnd, &ps);
+            return 0;
+
+        /* wait for the user to tell us when to quit */
+        case WM_CHAR:
+            switch (wP) {       /* only need one, so ignore repeat count */
+                case 'q':
+                case 'Q':
+                case 0x1B:      /* Esc key */
+                    PostQuitMessage(0);
+            }
+            return 0;
+
+        case WM_LBUTTONDOWN:    /* another way of quitting */
+        case WM_DESTROY:
+            PostQuitMessage(0);
+            return 0;
+    }
+
+    return DefWindowProc(hwnd, iMsg, wP, lP);
+}
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/rpng2-x.c b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/rpng2-x.c
index 6c687db..7f24b63 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/rpng2-x.c
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/rpng2-x.c
@@ -1,2107 +1,2107 @@
-/*---------------------------------------------------------------------------

-

-   rpng2 - progressive-model PNG display program                  rpng2-x.c

-

-   This program decodes and displays PNG files progressively, as if it were

-   a web browser (though the front end is only set up to read from files).

-   It supports gamma correction, user-specified background colors, and user-

-   specified background patterns (for transparent images).  This version is

-   for the X Window System (tested by the author under Unix and by Martin

-   Zinser under OpenVMS; may work under OS/2 with a little tweaking).

-

-   Thanks to Adam Costello and Pieter S. van der Meulen for the "diamond"

-   and "radial waves" patterns, respectively.

-

-   to do (someday, maybe):

-    - fix expose/redraw code:  don't draw entire row if only part exposed

-    - 8-bit (colormapped) X support

-    - finish resizable checkerboard-gradient (sizes 4-128?)

-    - use %.1023s to simplify truncation of title-bar string?

-

-  ---------------------------------------------------------------------------

-

-   Changelog:

-    - 1.01:  initial public release

-    - 1.02:  modified to allow abbreviated options; fixed char/uchar mismatch

-    - 1.10:  added support for non-default visuals; fixed X pixel-conversion

-    - 1.11:  added -usleep option for demos; fixed command-line parsing bug

-    - 1.12:  added -pause option for demos and testing

-    - 1.20:  added runtime MMX-enabling/disabling and new -mmx* options

-    - 1.21:  fixed some small X memory leaks (thanks to François Petitjean)

-    - 1.22:  fixed XFreeGC() crash bug (thanks to Patrick Welche)

-    - 1.23:  added -bgpat 0 mode (std white/gray checkerboard, 8x8 squares)

-    - 1.30:  added -loop option for -bgpat (ifdef FEATURE_LOOP); fixed bpp =

-              24; added support for X resources (thanks to Gerhard Niklasch)

-    - 1.31:  added code to skip unused chunks (thanks to Glenn Randers-Pehrson)

-    - 1.32:  added AMD64/EM64T support (__x86_64__); added basic expose/redraw

-              handling

-    - 2.00:  dual-licensed (added GNU GPL)

-    - 2.01:  fixed 64-bit typo in readpng2.c; fixed -pause usage description

-    - 2.02:  fixed improper display of usage screen on PNG error(s); fixed

-              unexpected-EOF and file-read-error cases; fixed Trace() cut-and-

-              paste bugs

-    - 2.03:  deleted runtime MMX-enabling/disabling and obsolete -mmx* options

-

-  ---------------------------------------------------------------------------

-

-      Copyright (c) 1998-2008 Greg Roelofs.  All rights reserved.

-

-      This software is provided "as is," without warranty of any kind,

-      express or implied.  In no event shall the author or contributors

-      be held liable for any damages arising in any way from the use of

-      this software.

-

-      The contents of this file are DUAL-LICENSED.  You may modify and/or

-      redistribute this software according to the terms of one of the

-      following two licenses (at your option):

-

-

-      LICENSE 1 ("BSD-like with advertising clause"):

-

-      Permission is granted to anyone to use this software for any purpose,

-      including commercial applications, and to alter it and redistribute

-      it freely, subject to the following restrictions:

-

-      1. Redistributions of source code must retain the above copyright

-         notice, disclaimer, and this list of conditions.

-      2. Redistributions in binary form must reproduce the above copyright

-         notice, disclaimer, and this list of conditions in the documenta-

-         tion and/or other materials provided with the distribution.

-      3. All advertising materials mentioning features or use of this

-         software must display the following acknowledgment:

-

-            This product includes software developed by Greg Roelofs

-            and contributors for the book, "PNG: The Definitive Guide,"

-            published by O'Reilly and Associates.

-

-

-      LICENSE 2 (GNU GPL v2 or later):

-

-      This program is free software; you can redistribute it and/or modify

-      it under the terms of the GNU General Public License as published by

-      the Free Software Foundation; either version 2 of the License, or

-      (at your option) any later version.

-

-      This program is distributed in the hope that it will be useful,

-      but WITHOUT ANY WARRANTY; without even the implied warranty of

-      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

-      GNU General Public License for more details.

-

-      You should have received a copy of the GNU General Public License

-      along with this program; if not, write to the Free Software Foundation,

-      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

-

-  ---------------------------------------------------------------------------*/

-

-#define PROGNAME  "rpng2-x"

-#define LONGNAME  "Progressive PNG Viewer for X"

-#define VERSION   "2.03 of 25 February 2010"

-#define RESNAME   "rpng2"       /* our X resource application name */

-#define RESCLASS  "Rpng"       /* our X resource class name */

-

-#include <stdio.h>

-#include <stdlib.h>

-#include <ctype.h>

-#include <string.h>

-#include <setjmp.h>       /* for jmpbuf declaration in readpng2.h */

-#include <time.h>

-#include <math.h>         /* only for PvdM background code */

-#include <X11/Xlib.h>

-#include <X11/Xutil.h>

-#include <X11/Xos.h>

-#include <X11/keysym.h>   /* defines XK_* macros */

-

-#ifdef VMS

-#  include <unistd.h>

-#endif

-

-/* all for PvdM background code: */

-#ifndef PI

-#  define PI             3.141592653589793238

-#endif

-#define PI_2             (PI*0.5)

-#define INV_PI_360       (360.0 / PI)

-#define MAX(a,b)         (a>b?a:b)

-#define MIN(a,b)         (a<b?a:b)

-#define CLIP(a,min,max)  MAX(min,MIN((a),max))

-#define ABS(a)           ((a)<0?-(a):(a))

-#define CLIP8P(c)        MAX(0,(MIN((c),255)))   /* 8-bit pos. integer (uch) */

-#define ROUNDF(f)        ((int)(f + 0.5))

-

-#define QUIT(e,k) ((e.type == ButtonPress && e.xbutton.button == Button1) ||  \

-                  (e.type == KeyPress &&   /*  v--- or 1 for shifted keys */  \

-                  ((k = XLookupKeysym(&e.xkey, 0)) == XK_q || k == XK_Escape)))

-

-#define NO_24BIT_MASKS /* undef case not fully written--only for redisplay() */

-

-#define rgb1_max   bg_freq

-#define rgb1_min   bg_gray

-#define rgb2_max   bg_bsat

-#define rgb2_min   bg_brot

-

-/* #define DEBUG */     /* this enables the Trace() macros */

-

-#include "readpng2.h"   /* typedefs, common macros, readpng2 prototypes */

-

-

-/* could just include png.h, but this macro is the only thing we need

- * (name and typedefs changed to local versions); note that side effects

- * only happen with alpha (which could easily be avoided with

- * "ush acopy = (alpha);") */

-

-#define alpha_composite(composite, fg, alpha, bg) {               \

-    ush temp = ((ush)(fg)*(ush)(alpha) +                          \

-                (ush)(bg)*(ush)(255 - (ush)(alpha)) + (ush)128);  \

-    (composite) = (uch)((temp + (temp >> 8)) >> 8);               \

-}

-

-

-#define INBUFSIZE 4096   /* with pseudo-timing on (1 sec delay/block), this

-                          *  block size corresponds roughly to a download

-                          *  speed 10% faster than theoretical 33.6K maximum

-                          *  (assuming 8 data bits, 1 stop bit and no other

-                          *  overhead) */

-

-/* local prototypes */

-static void rpng2_x_init (void);

-static int  rpng2_x_create_window (void);

-static int  rpng2_x_load_bg_image (void);

-static void rpng2_x_display_row (ulg row);

-static void rpng2_x_finish_display (void);

-static void rpng2_x_redisplay_image (ulg startcol, ulg startrow,

-                                     ulg width, ulg height);

-#ifdef FEATURE_LOOP

-static void rpng2_x_reload_bg_image (void);

-static int  is_number (char *p);

-#endif

-static void rpng2_x_cleanup (void);

-static int  rpng2_x_msb (ulg u32val);

-

-

-static char titlebar[1024], *window_name = titlebar;

-static char *appname = LONGNAME;

-static char *icon_name = PROGNAME;

-static char *res_name = RESNAME;

-static char *res_class = RESCLASS;

-static char *filename;

-static FILE *infile;

-

-static mainprog_info rpng2_info;

-

-static uch inbuf[INBUFSIZE];

-static int incount;

-

-static int pat = 6;        /* must be less than num_bgpat */

-static int bg_image = 0;

-static int bgscale, bgscale_default = 16;

-static ulg bg_rowbytes;

-static uch *bg_data;

-

-int pause_after_pass = FALSE;

-int demo_timing = FALSE;

-ulg usleep_duration = 0L;

-

-static struct rgb_color {

-    uch r, g, b;

-} rgb[] = {

-    {  0,   0,   0},    /*  0:  black */

-    {255, 255, 255},    /*  1:  white */

-    {173, 132,  57},    /*  2:  tan */

-    { 64, 132,   0},    /*  3:  medium green */

-    {189, 117,   1},    /*  4:  gold */

-    {253, 249,   1},    /*  5:  yellow */

-    {  0,   0, 255},    /*  6:  blue */

-    {  0,   0, 120},    /*  7:  medium blue */

-    {255,   0, 255},    /*  8:  magenta */

-    { 64,   0,  64},    /*  9:  dark magenta */

-    {255,   0,   0},    /* 10:  red */

-    { 64,   0,   0},    /* 11:  dark red */

-    {255, 127,   0},    /* 12:  orange */

-    {192,  96,   0},    /* 13:  darker orange */

-    { 24,  60,   0},    /* 14:  dark green-yellow */

-    { 85, 125, 200},    /* 15:  ice blue */

-    {192, 192, 192}     /* 16:  Netscape/Mosaic gray */

-};

-/* not used for now, but should be for error-checking:

-static int num_rgb = sizeof(rgb) / sizeof(struct rgb_color);

- */

-

-/*

-    This whole struct is a fairly cheesy way to keep the number of

-    command-line options to a minimum.  The radial-waves background

-    type is a particularly poor fit to the integer elements of the

-    struct...but a few macros and a little fixed-point math will do

-    wonders for ya.

-

-    type bits:

-       F E D C B A 9 8 7 6 5 4 3 2 1 0

-                             | | | | |

-                             | | +-+-+-- 0 = sharp-edged checkerboard

-                             | |         1 = soft diamonds

-                             | |         2 = radial waves

-                             | |       3-7 = undefined

-                             | +-- gradient #2 inverted?

-                             +-- alternating columns inverted?

- */

-static struct background_pattern {

-    ush type;

-    int rgb1_max, rgb1_min;     /* or bg_freq, bg_gray */

-    int rgb2_max, rgb2_min;     /* or bg_bsat, bg_brot (both scaled by 10)*/

-} bg[] = {

-    {0,     1,1, 16,16},        /* checkered:  white vs. light gray (basic) */

-    {0+8,   2,0,  1,15},        /* checkered:  tan/black vs. white/ice blue */

-    {0+24,  2,0,  1,0},         /* checkered:  tan/black vs. white/black */

-    {0+8,   4,5,  0,2},         /* checkered:  gold/yellow vs. black/tan */

-    {0+8,   4,5,  0,6},         /* checkered:  gold/yellow vs. black/blue */

-    {0,     7,0,  8,9},         /* checkered:  deep blue/black vs. magenta */

-    {0+8,  13,0,  5,14},        /* checkered:  orange/black vs. yellow */

-    {0+8,  12,0, 10,11},        /* checkered:  orange/black vs. red */

-    {1,     7,0,  8,0},         /* diamonds:  deep blue/black vs. magenta */

-    {1,    12,0, 11,0},         /* diamonds:  orange vs. dark red */

-    {1,    10,0,  7,0},         /* diamonds:  red vs. medium blue */

-    {1,     4,0,  5,0},         /* diamonds:  gold vs. yellow */

-    {1,     3,0,  0,0},         /* diamonds:  medium green vs. black */

-    {2,    16, 100,  20,   0},  /* radial:  ~hard radial color-beams */

-    {2,    18, 100,  10,   2},  /* radial:  soft, curved radial color-beams */

-    {2,    16, 256, 100, 250},  /* radial:  very tight spiral */

-    {2, 10000, 256,  11,   0}   /* radial:  dipole-moire' (almost fractal) */

-};

-static int num_bgpat = sizeof(bg) / sizeof(struct background_pattern);

-

-

-/* X-specific variables */

-static char *displayname;

-static XImage *ximage;

-static Display *display;

-static int depth;

-static Visual *visual;

-static XVisualInfo *visual_list;

-static int RShift, GShift, BShift;

-static ulg RMask, GMask, BMask;

-static Window window;

-static GC gc;

-static Colormap colormap;

-

-static int have_nondefault_visual = FALSE;

-static int have_colormap = FALSE;

-static int have_window = FALSE;

-static int have_gc = FALSE;

-

-

-

-

-int main(int argc, char **argv)

-{

-#ifdef sgi

-    char tmpline[80];

-#endif

-    char *p, *bgstr = NULL;

-    int rc, alen, flen;

-    int error = 0;

-    int timing = FALSE;

-    int have_bg = FALSE;

-#ifdef FEATURE_LOOP

-    int loop = FALSE;

-    long loop_interval = -1;            /* seconds (100,000 max) */

-#endif

-    double LUT_exponent;                /* just the lookup table */

-    double CRT_exponent = 2.2;          /* just the monitor */

-    double default_display_exponent;    /* whole display system */

-    XEvent e;

-    KeySym k;

-

-

-    /* First initialize a few things, just to be sure--memset takes care of

-     * default background color (black), booleans (FALSE), pointers (NULL),

-     * etc. */

-

-    displayname = (char *)NULL;

-    filename = (char *)NULL;

-    memset(&rpng2_info, 0, sizeof(mainprog_info));

-

-

-    /* Set the default value for our display-system exponent, i.e., the

-     * product of the CRT exponent and the exponent corresponding to

-     * the frame-buffer's lookup table (LUT), if any.  This is not an

-     * exhaustive list of LUT values (e.g., OpenStep has a lot of weird

-     * ones), but it should cover 99% of the current possibilities. */

-

-#if defined(NeXT)

-    /* third-party utilities can modify the default LUT exponent */

-    LUT_exponent = 1.0 / 2.2;

-    /*

-    if (some_next_function_that_returns_gamma(&next_gamma))

-        LUT_exponent = 1.0 / next_gamma;

-     */

-#elif defined(sgi)

-    LUT_exponent = 1.0 / 1.7;

-    /* there doesn't seem to be any documented function to

-     * get the "gamma" value, so we do it the hard way */

-    infile = fopen("/etc/config/system.glGammaVal", "r");

-    if (infile) {

-        double sgi_gamma;

-

-        fgets(tmpline, 80, infile);

-        fclose(infile);

-        sgi_gamma = atof(tmpline);

-        if (sgi_gamma > 0.0)

-            LUT_exponent = 1.0 / sgi_gamma;

-    }

-#elif defined(Macintosh)

-    LUT_exponent = 1.8 / 2.61;

-    /*

-    if (some_mac_function_that_returns_gamma(&mac_gamma))

-        LUT_exponent = mac_gamma / 2.61;

-     */

-#else

-    LUT_exponent = 1.0;   /* assume no LUT:  most PCs */

-#endif

-

-    /* the defaults above give 1.0, 1.3, 1.5 and 2.2, respectively: */

-    default_display_exponent = LUT_exponent * CRT_exponent;

-

-

-    /* If the user has set the SCREEN_GAMMA environment variable as suggested

-     * (somewhat imprecisely) in the libpng documentation, use that; otherwise

-     * use the default value we just calculated.  Either way, the user may

-     * override this via a command-line option. */

-

-    if ((p = getenv("SCREEN_GAMMA")) != NULL)

-        rpng2_info.display_exponent = atof(p);

-    else

-        rpng2_info.display_exponent = default_display_exponent;

-

-

-    /* Now parse the command line for options and the PNG filename. */

-

-    while (*++argv && !error) {

-        if (!strncmp(*argv, "-display", 2)) {

-            if (!*++argv)

-                ++error;

-            else

-                displayname = *argv;

-        } else if (!strncmp(*argv, "-gamma", 2)) {

-            if (!*++argv)

-                ++error;

-            else {

-                rpng2_info.display_exponent = atof(*argv);

-                if (rpng2_info.display_exponent <= 0.0)

-                    ++error;

-            }

-        } else if (!strncmp(*argv, "-bgcolor", 4)) {

-            if (!*++argv)

-                ++error;

-            else {

-                bgstr = *argv;

-                if (strlen(bgstr) != 7 || bgstr[0] != '#')

-                    ++error;

-                else {

-                    have_bg = TRUE;

-                    bg_image = FALSE;

-                }

-            }

-        } else if (!strncmp(*argv, "-bgpat", 4)) {

-            if (!*++argv)

-                ++error;

-            else {

-                pat = atoi(*argv);

-                if (pat >= 0 && pat < num_bgpat) {

-                    bg_image = TRUE;

-                    have_bg = FALSE;

-                } else

-                    ++error;

-            }

-        } else if (!strncmp(*argv, "-usleep", 2)) {

-            if (!*++argv)

-                ++error;

-            else {

-                usleep_duration = (ulg)atol(*argv);

-                demo_timing = TRUE;

-            }

-        } else if (!strncmp(*argv, "-pause", 2)) {

-            pause_after_pass = TRUE;

-        } else if (!strncmp(*argv, "-timing", 2)) {

-            timing = TRUE;

-#ifdef FEATURE_LOOP

-        } else if (!strncmp(*argv, "-loop", 2)) {

-            loop = TRUE;

-            if (!argv[1] || !is_number(argv[1]))

-                loop_interval = 2;

-            else {

-                ++argv;

-                loop_interval = atol(*argv);

-                if (loop_interval < 0)

-                    loop_interval = 2;

-                else if (loop_interval > 100000)   /* bit more than one day */

-                    loop_interval = 100000;

-            }

-#endif

-        } else {

-            if (**argv != '-') {

-                filename = *argv;

-                if (argv[1])   /* shouldn't be any more args after filename */

-                    ++error;

-            } else

-                ++error;   /* not expecting any other options */

-        }

-    }

-

-    if (!filename)

-        ++error;

-

-

-    /* print usage screen if any errors up to this point */

-

-    if (error) {

-        fprintf(stderr, "\n%s %s:  %s\n\n", PROGNAME, VERSION, appname);

-        readpng2_version_info();

-        fprintf(stderr, "\n"

-          "Usage:  %s [-display xdpy] [-gamma exp] [-bgcolor bg | -bgpat pat]\n"

-#ifdef FEATURE_LOOP

-          "        %*s [-usleep dur | -timing] [-pause] [-loop [sec]] file.png\n\n"

-#else

-          "        %*s [-usleep dur | -timing] [-pause] file.png\n\n"

-#endif

-          "    xdpy\tname of the target X display (e.g., ``hostname:0'')\n"

-          "    exp \ttransfer-function exponent (``gamma'') of the display\n"

-          "\t\t  system in floating-point format (e.g., ``%.1f''); equal\n"

-          "\t\t  to the product of the lookup-table exponent (varies)\n"

-          "\t\t  and the CRT exponent (usually 2.2); must be positive\n"

-          "    bg  \tdesired background color in 7-character hex RGB format\n"

-          "\t\t  (e.g., ``#ff7700'' for orange:  same as HTML colors);\n"

-          "\t\t  used with transparent images; overrides -bgpat\n"

-          "    pat \tdesired background pattern number (0-%d); used with\n"

-          "\t\t  transparent images; overrides -bgcolor\n"

-#ifdef FEATURE_LOOP

-          "    -loop\tloops through background images after initial display\n"

-          "\t\t  is complete (depends on -bgpat)\n"

-          "    sec \tseconds to display each background image (default = 2)\n"

-#endif

-          "    dur \tduration in microseconds to wait after displaying each\n"

-          "\t\t  row (for demo purposes)\n"

-          "    -timing\tenables delay for every block read, to simulate modem\n"

-          "\t\t  download of image (~36 Kbps)\n"

-          "    -pause\tpauses after displaying each pass until mouse clicked\n"

-          "\nPress Q, Esc or mouse button 1 (within image window, after image\n"

-          "is displayed) to quit.\n"

-          "\n", PROGNAME,

-          (int)strlen(PROGNAME), " ", default_display_exponent, num_bgpat-1);

-        exit(1);

-    }

-

-

-    if (!(infile = fopen(filename, "rb"))) {

-        fprintf(stderr, PROGNAME ":  can't open PNG file [%s]\n", filename);

-        ++error;

-    } else {

-        incount = fread(inbuf, 1, INBUFSIZE, infile);

-        if (incount < 8 || !readpng2_check_sig(inbuf, 8)) {

-            fprintf(stderr, PROGNAME

-              ":  [%s] is not a PNG file: incorrect signature\n",

-              filename);

-            ++error;

-        } else if ((rc = readpng2_init(&rpng2_info)) != 0) {

-            switch (rc) {

-                case 2:

-                    fprintf(stderr, PROGNAME

-                      ":  [%s] has bad IHDR (libpng longjmp)\n", filename);

-                    break;

-                case 4:

-                    fprintf(stderr, PROGNAME ":  insufficient memory\n");

-                    break;

-                default:

-                    fprintf(stderr, PROGNAME

-                      ":  unknown readpng2_init() error\n");

-                    break;

-            }

-            ++error;

-        } else {

-            Trace((stderr, "about to call XOpenDisplay()\n"))

-            display = XOpenDisplay(displayname);

-            if (!display) {

-                readpng2_cleanup(&rpng2_info);

-                fprintf(stderr, PROGNAME ":  can't open X display [%s]\n",

-                  displayname? displayname : "default");

-                ++error;

-            }

-        }

-        if (error)

-            fclose(infile);

-    }

-

-

-    if (error) {

-        fprintf(stderr, PROGNAME ":  aborting.\n");

-        exit(2);

-    }

-

-

-    /* set the title-bar string, but make sure buffer doesn't overflow */

-

-    alen = strlen(appname);

-    flen = strlen(filename);

-    if (alen + flen + 3 > 1023)

-        sprintf(titlebar, "%s:  ...%s", appname, filename+(alen+flen+6-1023));

-    else

-        sprintf(titlebar, "%s:  %s", appname, filename);

-

-

-    /* set some final rpng2_info variables before entering main data loop */

-

-    if (have_bg) {

-        unsigned r, g, b;   /* this approach quiets compiler warnings */

-

-        sscanf(bgstr+1, "%2x%2x%2x", &r, &g, &b);

-        rpng2_info.bg_red   = (uch)r;

-        rpng2_info.bg_green = (uch)g;

-        rpng2_info.bg_blue  = (uch)b;

-    } else

-        rpng2_info.need_bgcolor = TRUE;

-

-    rpng2_info.state = kPreInit;

-    rpng2_info.mainprog_init = rpng2_x_init;

-    rpng2_info.mainprog_display_row = rpng2_x_display_row;

-    rpng2_info.mainprog_finish_display = rpng2_x_finish_display;

-

-

-    /* OK, this is the fun part:  call readpng2_decode_data() at the start of

-     * the loop to deal with our first buffer of data (read in above to verify

-     * that the file is a PNG image), then loop through the file and continue

-     * calling the same routine to handle each chunk of data.  It in turn

-     * passes the data to libpng, which will invoke one or more of our call-

-     * backs as decoded data become available.  We optionally call sleep() for

-     * one second per iteration to simulate downloading the image via an analog

-     * modem. */

-

-    for (;;) {

-        Trace((stderr, "about to call readpng2_decode_data()\n"))

-        if (readpng2_decode_data(&rpng2_info, inbuf, incount))

-            ++error;

-        Trace((stderr, "done with readpng2_decode_data()\n"))

-

-        if (error || incount != INBUFSIZE || rpng2_info.state == kDone) {

-            if (rpng2_info.state == kDone) {

-                Trace((stderr, "done decoding PNG image\n"))

-            } else if (ferror(infile)) {

-                fprintf(stderr, PROGNAME

-                  ":  error while reading PNG image file\n");

-                exit(3);

-            } else if (feof(infile)) {

-                fprintf(stderr, PROGNAME ":  end of file reached "

-                  "(unexpectedly) while reading PNG image file\n");

-                exit(3);

-            } else /* if (error) */ {

-                /* will print error message below */

-            }

-            break;

-        }

-

-        if (timing)

-            sleep(1);

-

-        incount = fread(inbuf, 1, INBUFSIZE, infile);

-    }

-

-

-    /* clean up PNG stuff and report any decoding errors */

-

-    fclose(infile);

-    Trace((stderr, "about to call readpng2_cleanup()\n"))

-    readpng2_cleanup(&rpng2_info);

-

-    if (error) {

-        fprintf(stderr, PROGNAME ":  libpng error while decoding PNG image\n");

-        exit(3);

-    }

-

-

-#ifdef FEATURE_LOOP

-

-    if (loop && bg_image) {

-        Trace((stderr, "entering -loop loop (FEATURE_LOOP)\n"))

-        for (;;) {

-            int i, use_sleep;

-            struct timeval now, then;

-

-            /* get current time and add loop_interval to get target time */

-            if (gettimeofday(&then, NULL) == 0) {

-                then.tv_sec += loop_interval;

-                use_sleep = FALSE;

-            } else

-                use_sleep = TRUE;

-

-            /* do quick check for a quit event but don't wait for it */

-            /* GRR BUG:  should also check for Expose events and redraw... */

-            if (XCheckMaskEvent(display, KeyPressMask | ButtonPressMask, &e))

-                if (QUIT(e,k))

-                    break;

-

-            /* generate next background image */

-            if (++pat >= num_bgpat)

-                pat = 0;

-            rpng2_x_reload_bg_image();

-

-            /* wait for timeout, using whatever means are available */

-            if (use_sleep || gettimeofday(&now, NULL) != 0) {

-                for (i = loop_interval;  i > 0;  --i) {

-                    sleep(1);

-                    /* GRR BUG:  also need to check for Expose (and redraw!) */

-                    if (XCheckMaskEvent(display, KeyPressMask | ButtonPressMask,

-                        &e) && QUIT(e,k))

-                        break;

-                }

-            } else {

-                /* Y2038 BUG! */

-                if (now.tv_sec < then.tv_sec ||

-                    (now.tv_sec == then.tv_sec && now.tv_usec < then.tv_usec))

-                {

-                    int quit = FALSE;

-                    long seconds_to_go = then.tv_sec - now.tv_sec;

-                    long usleep_usec;

-

-                    /* basically chew up most of remaining loop-interval with

-                     *  calls to sleep(1) interleaved with checks for quit

-                     *  events, but also recalc time-to-go periodically; when

-                     *  done, clean up any remaining time with usleep() call

-                     *  (could also use SIGALRM, but signals are a pain...) */

-                    while (seconds_to_go-- > 1) {

-                        int seconds_done = 0;

-

-                        for (i = seconds_to_go;  i > 0 && !quit;  --i) {

-                            sleep(1);

-                            /* GRR BUG:  need to check for Expose and redraw */

-                            if (XCheckMaskEvent(display, KeyPressMask |

-                                ButtonPressMask, &e) && QUIT(e,k))

-                                quit = TRUE;

-                            if (++seconds_done > 1000)

-                                break;   /* time to redo seconds_to_go meas. */

-                        }

-                        if (quit)

-                            break;

-

-                        /* OK, more than 1000 seconds since last check:

-                         *  correct the time-to-go measurement for drift */

-                        if (gettimeofday(&now, NULL) == 0) {

-                            if (now.tv_sec >= then.tv_sec)

-                                break;

-                            seconds_to_go = then.tv_sec - now.tv_sec;

-                        } else

-                            ++seconds_to_go;  /* restore what we subtracted */

-                    }

-                    if (quit)

-                        break;   /* breaks outer do-loop, skips redisplay */

-

-                    /* since difference between "now" and "then" is already

-                     *  eaten up to within a couple of seconds, don't need to

-                     *  worry about overflow--but might have overshot (neg.) */

-                    if (gettimeofday(&now, NULL) == 0) {

-                        usleep_usec = 1000000L*(then.tv_sec - now.tv_sec) +

-                          then.tv_usec - now.tv_usec;

-                        if (usleep_usec > 0)

-                            usleep((ulg)usleep_usec);

-                    }

-                }

-            }

-

-            /* composite image against new background and display (note that

-             *  we do not take into account the time spent doing this...) */

-            rpng2_x_redisplay_image (0, 0, rpng2_info.width, rpng2_info.height);

-        }

-

-    } else /* FALL THROUGH and do the normal thing */

-

-#endif /* FEATURE_LOOP */

-

-    /* wait for the user to tell us when to quit */

-

-    if (rpng2_info.state >= kWindowInit) {

-        Trace((stderr, "entering final wait-for-quit-event loop\n"))

-        do {

-            XNextEvent(display, &e);

-            if (e.type == Expose) {

-                XExposeEvent *ex = (XExposeEvent *)&e;

-                rpng2_x_redisplay_image (ex->x, ex->y, ex->width, ex->height);

-            }

-        } while (!QUIT(e,k));

-    } else {

-        fprintf(stderr, PROGNAME ":  init callback never called:  probable "

-          "libpng error while decoding PNG metadata\n");

-        exit(4);

-    }

-

-

-    /* we're done:  clean up all image and X resources and go away */

-

-    Trace((stderr, "about to call rpng2_x_cleanup()\n"))

-    rpng2_x_cleanup();

-

-    return 0;

-}

-

-

-

-

-

-/* this function is called by readpng2_info_callback() in readpng2.c, which

- * in turn is called by libpng after all of the pre-IDAT chunks have been

- * read and processed--i.e., we now have enough info to finish initializing */

-

-static void rpng2_x_init(void)

-{

-    ulg i;

-    ulg rowbytes = rpng2_info.rowbytes;

-

-    Trace((stderr, "beginning rpng2_x_init()\n"))

-    Trace((stderr, "  rowbytes = %d\n", rpng2_info.rowbytes))

-    Trace((stderr, "  width  = %ld\n", rpng2_info.width))

-    Trace((stderr, "  height = %ld\n", rpng2_info.height))

-

-    rpng2_info.image_data = (uch *)malloc(rowbytes * rpng2_info.height);

-    if (!rpng2_info.image_data) {

-        readpng2_cleanup(&rpng2_info);

-        return;

-    }

-

-    rpng2_info.row_pointers = (uch **)malloc(rpng2_info.height * sizeof(uch *));

-    if (!rpng2_info.row_pointers) {

-        free(rpng2_info.image_data);

-        rpng2_info.image_data = NULL;

-        readpng2_cleanup(&rpng2_info);

-        return;

-    }

-

-    for (i = 0;  i < rpng2_info.height;  ++i)

-        rpng2_info.row_pointers[i] = rpng2_info.image_data + i*rowbytes;

-

-

-    /* do the basic X initialization stuff, make the window, and fill it with

-     * the user-specified, file-specified or default background color or

-     * pattern */

-

-    if (rpng2_x_create_window()) {

-

-        /* GRR TEMPORARY HACK:  this is fundamentally no different from cases

-         * above; libpng should call our error handler to longjmp() back to us

-         * when png_ptr goes away.  If we/it segfault instead, seems like a

-         * libpng bug... */

-

-        /* we're here via libpng callback, so if window fails, clean and bail */

-        readpng2_cleanup(&rpng2_info);

-        rpng2_x_cleanup();

-        exit(2);

-    }

-

-    rpng2_info.state = kWindowInit;

-}

-

-

-

-

-

-static int rpng2_x_create_window(void)

-{

-    ulg bg_red   = rpng2_info.bg_red;

-    ulg bg_green = rpng2_info.bg_green;

-    ulg bg_blue  = rpng2_info.bg_blue;

-    ulg bg_pixel = 0L;

-    ulg attrmask;

-    int need_colormap = FALSE;

-    int screen, pad;

-    uch *xdata;

-    Window root;

-    XEvent e;

-    XGCValues gcvalues;

-    XSetWindowAttributes attr;

-    XTextProperty windowName, *pWindowName = &windowName;

-    XTextProperty iconName, *pIconName = &iconName;

-    XVisualInfo visual_info;

-    XSizeHints *size_hints;

-    XWMHints *wm_hints;

-    XClassHint *class_hints;

-

-

-    Trace((stderr, "beginning rpng2_x_create_window()\n"))

-

-    screen = DefaultScreen(display);

-    depth = DisplayPlanes(display, screen);

-    root = RootWindow(display, screen);

-

-#ifdef DEBUG

-    XSynchronize(display, True);

-#endif

-

-    if (depth != 16 && depth != 24 && depth != 32) {

-        int visuals_matched = 0;

-

-        Trace((stderr, "default depth is %d:  checking other visuals\n",

-          depth))

-

-        /* 24-bit first */

-        visual_info.screen = screen;

-        visual_info.depth = 24;

-        visual_list = XGetVisualInfo(display,

-          VisualScreenMask | VisualDepthMask, &visual_info, &visuals_matched);

-        if (visuals_matched == 0) {

-/* GRR:  add 15-, 16- and 32-bit TrueColor visuals (also DirectColor?) */

-            fprintf(stderr, "default screen depth %d not supported, and no"

-              " 24-bit visuals found\n", depth);

-            return 2;

-        }

-        Trace((stderr, "XGetVisualInfo() returned %d 24-bit visuals\n",

-          visuals_matched))

-        visual = visual_list[0].visual;

-        depth = visual_list[0].depth;

-/*

-        colormap_size = visual_list[0].colormap_size;

-        visual_class = visual->class;

-        visualID = XVisualIDFromVisual(visual);

- */

-        have_nondefault_visual = TRUE;

-        need_colormap = TRUE;

-    } else {

-        XMatchVisualInfo(display, screen, depth, TrueColor, &visual_info);

-        visual = visual_info.visual;

-    }

-

-    RMask = visual->red_mask;

-    GMask = visual->green_mask;

-    BMask = visual->blue_mask;

-

-/* GRR:  add/check 8-bit support */

-    if (depth == 8 || need_colormap) {

-        colormap = XCreateColormap(display, root, visual, AllocNone);

-        if (!colormap) {

-            fprintf(stderr, "XCreateColormap() failed\n");

-            return 2;

-        }

-        have_colormap = TRUE;

-        if (depth == 8)

-            bg_image = FALSE;   /* gradient just wastes palette entries */

-    }

-    if (depth == 15 || depth == 16) {

-        RShift = 15 - rpng2_x_msb(RMask);    /* these are right-shifts */

-        GShift = 15 - rpng2_x_msb(GMask);

-        BShift = 15 - rpng2_x_msb(BMask);

-    } else if (depth > 16) {

-        RShift = rpng2_x_msb(RMask) - 7;     /* these are left-shifts */

-        GShift = rpng2_x_msb(GMask) - 7;

-        BShift = rpng2_x_msb(BMask) - 7;

-    }

-    if (depth >= 15 && (RShift < 0 || GShift < 0 || BShift < 0)) {

-        fprintf(stderr, "rpng2 internal logic error:  negative X shift(s)!\n");

-        return 2;

-    }

-

-/*---------------------------------------------------------------------------

-    Finally, create the window.

-  ---------------------------------------------------------------------------*/

-

-    attr.backing_store = Always;

-    attr.event_mask = ExposureMask | KeyPressMask | ButtonPressMask;

-    attrmask = CWBackingStore | CWEventMask;

-    if (have_nondefault_visual) {

-        attr.colormap = colormap;

-        attr.background_pixel = 0;

-        attr.border_pixel = 1;

-        attrmask |= CWColormap | CWBackPixel | CWBorderPixel;

-    }

-

-    window = XCreateWindow(display, root, 0, 0, rpng2_info.width,

-      rpng2_info.height, 0, depth, InputOutput, visual, attrmask, &attr);

-

-    if (window == None) {

-        fprintf(stderr, "XCreateWindow() failed\n");

-        return 2;

-    } else

-        have_window = TRUE;

-

-    if (depth == 8)

-        XSetWindowColormap(display, window, colormap);

-

-    if (!XStringListToTextProperty(&window_name, 1, pWindowName))

-        pWindowName = NULL;

-    if (!XStringListToTextProperty(&icon_name, 1, pIconName))

-        pIconName = NULL;

-

-    /* OK if either hints allocation fails; XSetWMProperties() allows NULLs */

-

-    if ((size_hints = XAllocSizeHints()) != NULL) {

-        /* window will not be resizable */

-        size_hints->flags = PMinSize | PMaxSize;

-        size_hints->min_width = size_hints->max_width = (int)rpng2_info.width;

-        size_hints->min_height = size_hints->max_height =

-          (int)rpng2_info.height;

-    }

-

-    if ((wm_hints = XAllocWMHints()) != NULL) {

-        wm_hints->initial_state = NormalState;

-        wm_hints->input = True;

-     /* wm_hints->icon_pixmap = icon_pixmap; */

-        wm_hints->flags = StateHint | InputHint  /* | IconPixmapHint */ ;

-    }

-

-    if ((class_hints = XAllocClassHint()) != NULL) {

-        class_hints->res_name = res_name;

-        class_hints->res_class = res_class;

-    }

-

-    XSetWMProperties(display, window, pWindowName, pIconName, NULL, 0,

-      size_hints, wm_hints, class_hints);

-

-    /* various properties and hints no longer needed; free memory */

-    if (pWindowName)

-       XFree(pWindowName->value);

-    if (pIconName)

-       XFree(pIconName->value);

-    if (size_hints)

-        XFree(size_hints);

-    if (wm_hints)

-       XFree(wm_hints);

-    if (class_hints)

-       XFree(class_hints);

-

-    XMapWindow(display, window);

-

-    gc = XCreateGC(display, window, 0, &gcvalues);

-    have_gc = TRUE;

-

-/*---------------------------------------------------------------------------

-    Allocate memory for the X- and display-specific version of the image.

-  ---------------------------------------------------------------------------*/

-

-    if (depth == 24 || depth == 32) {

-        xdata = (uch *)malloc(4*rpng2_info.width*rpng2_info.height);

-        pad = 32;

-    } else if (depth == 16) {

-        xdata = (uch *)malloc(2*rpng2_info.width*rpng2_info.height);

-        pad = 16;

-    } else /* depth == 8 */ {

-        xdata = (uch *)malloc(rpng2_info.width*rpng2_info.height);

-        pad = 8;

-    }

-

-    if (!xdata) {

-        fprintf(stderr, PROGNAME ":  unable to allocate image memory\n");

-        return 4;

-    }

-

-    ximage = XCreateImage(display, visual, depth, ZPixmap, 0,

-      (char *)xdata, rpng2_info.width, rpng2_info.height, pad, 0);

-

-    if (!ximage) {

-        fprintf(stderr, PROGNAME ":  XCreateImage() failed\n");

-        free(xdata);

-        return 3;

-    }

-

-    /* to avoid testing the byte order every pixel (or doubling the size of

-     * the drawing routine with a giant if-test), we arbitrarily set the byte

-     * order to MSBFirst and let Xlib worry about inverting things on little-

-     * endian machines (e.g., Linux/x86, old VAXen, etc.)--this is not the

-     * most efficient approach (the giant if-test would be better), but in

-     * the interest of clarity, we'll take the easy way out... */

-

-    ximage->byte_order = MSBFirst;

-

-/*---------------------------------------------------------------------------

-    Fill window with the specified background color (default is black) or

-    faked "background image" (but latter is disabled if 8-bit; gradients

-    just waste palette entries).

-  ---------------------------------------------------------------------------*/

-

-    if (bg_image)

-        rpng2_x_load_bg_image();    /* resets bg_image if fails */

-

-    if (!bg_image) {

-        if (depth == 24 || depth == 32) {

-            bg_pixel = (bg_red   << RShift) |

-                       (bg_green << GShift) |

-                       (bg_blue  << BShift);

-        } else if (depth == 16) {

-            bg_pixel = (((bg_red   << 8) >> RShift) & RMask) |

-                       (((bg_green << 8) >> GShift) & GMask) |

-                       (((bg_blue  << 8) >> BShift) & BMask);

-        } else /* depth == 8 */ {

-

-            /* GRR:  add 8-bit support */

-

-        }

-        XSetForeground(display, gc, bg_pixel);

-        XFillRectangle(display, window, gc, 0, 0, rpng2_info.width,

-          rpng2_info.height);

-    }

-

-/*---------------------------------------------------------------------------

-    Wait for first Expose event to do any drawing, then flush and return.

-  ---------------------------------------------------------------------------*/

-

-    do

-        XNextEvent(display, &e);

-    while (e.type != Expose || e.xexpose.count);

-

-    XFlush(display);

-

-    return 0;

-

-} /* end function rpng2_x_create_window() */

-

-

-

-

-

-static int rpng2_x_load_bg_image(void)

-{

-    uch *src;

-    char *dest;

-    uch r1, r2, g1, g2, b1, b2;

-    uch r1_inv, r2_inv, g1_inv, g2_inv, b1_inv, b2_inv;

-    int k, hmax, max;

-    int xidx, yidx, yidx_max;

-    int even_odd_vert, even_odd_horiz, even_odd;

-    int invert_gradient2 = (bg[pat].type & 0x08);

-    int invert_column;

-    int ximage_rowbytes = ximage->bytes_per_line;

-    ulg i, row;

-    ulg pixel;

-

-/*---------------------------------------------------------------------------

-    Allocate buffer for fake background image to be used with transparent

-    images; if this fails, revert to plain background color.

-  ---------------------------------------------------------------------------*/

-

-    bg_rowbytes = 3 * rpng2_info.width;

-    bg_data = (uch *)malloc(bg_rowbytes * rpng2_info.height);

-    if (!bg_data) {

-        fprintf(stderr, PROGNAME

-          ":  unable to allocate memory for background image\n");

-        bg_image = 0;

-        return 1;

-    }

-

-    bgscale = (pat == 0)? 8 : bgscale_default;

-    yidx_max = bgscale - 1;

-

-/*---------------------------------------------------------------------------

-    Vertical gradients (ramps) in NxN squares, alternating direction and

-    colors (N == bgscale).

-  ---------------------------------------------------------------------------*/

-

-    if ((bg[pat].type & 0x07) == 0) {

-        uch r1_min  = rgb[bg[pat].rgb1_min].r;

-        uch g1_min  = rgb[bg[pat].rgb1_min].g;

-        uch b1_min  = rgb[bg[pat].rgb1_min].b;

-        uch r2_min  = rgb[bg[pat].rgb2_min].r;

-        uch g2_min  = rgb[bg[pat].rgb2_min].g;

-        uch b2_min  = rgb[bg[pat].rgb2_min].b;

-        int r1_diff = rgb[bg[pat].rgb1_max].r - r1_min;

-        int g1_diff = rgb[bg[pat].rgb1_max].g - g1_min;

-        int b1_diff = rgb[bg[pat].rgb1_max].b - b1_min;

-        int r2_diff = rgb[bg[pat].rgb2_max].r - r2_min;

-        int g2_diff = rgb[bg[pat].rgb2_max].g - g2_min;

-        int b2_diff = rgb[bg[pat].rgb2_max].b - b2_min;

-

-        for (row = 0;  row < rpng2_info.height;  ++row) {

-            yidx = (int)(row % bgscale);

-            even_odd_vert = (int)((row / bgscale) & 1);

-

-            r1 = r1_min + (r1_diff * yidx) / yidx_max;

-            g1 = g1_min + (g1_diff * yidx) / yidx_max;

-            b1 = b1_min + (b1_diff * yidx) / yidx_max;

-            r1_inv = r1_min + (r1_diff * (yidx_max-yidx)) / yidx_max;

-            g1_inv = g1_min + (g1_diff * (yidx_max-yidx)) / yidx_max;

-            b1_inv = b1_min + (b1_diff * (yidx_max-yidx)) / yidx_max;

-

-            r2 = r2_min + (r2_diff * yidx) / yidx_max;

-            g2 = g2_min + (g2_diff * yidx) / yidx_max;

-            b2 = b2_min + (b2_diff * yidx) / yidx_max;

-            r2_inv = r2_min + (r2_diff * (yidx_max-yidx)) / yidx_max;

-            g2_inv = g2_min + (g2_diff * (yidx_max-yidx)) / yidx_max;

-            b2_inv = b2_min + (b2_diff * (yidx_max-yidx)) / yidx_max;

-

-            dest = (char *)bg_data + row*bg_rowbytes;

-            for (i = 0;  i < rpng2_info.width;  ++i) {

-                even_odd_horiz = (int)((i / bgscale) & 1);

-                even_odd = even_odd_vert ^ even_odd_horiz;

-                invert_column =

-                  (even_odd_horiz && (bg[pat].type & 0x10));

-                if (even_odd == 0) {        /* gradient #1 */

-                    if (invert_column) {

-                        *dest++ = r1_inv;

-                        *dest++ = g1_inv;

-                        *dest++ = b1_inv;

-                    } else {

-                        *dest++ = r1;

-                        *dest++ = g1;

-                        *dest++ = b1;

-                    }

-                } else {                    /* gradient #2 */

-                    if ((invert_column && invert_gradient2) ||

-                        (!invert_column && !invert_gradient2))

-                    {

-                        *dest++ = r2;       /* not inverted or */

-                        *dest++ = g2;       /*  doubly inverted */

-                        *dest++ = b2;

-                    } else {

-                        *dest++ = r2_inv;

-                        *dest++ = g2_inv;   /* singly inverted */

-                        *dest++ = b2_inv;

-                    }

-                }

-            }

-        }

-

-/*---------------------------------------------------------------------------

-    Soft gradient-diamonds with scale = bgscale.  Code contributed by Adam

-    M. Costello.

-  ---------------------------------------------------------------------------*/

-

-    } else if ((bg[pat].type & 0x07) == 1) {

-

-        hmax = (bgscale-1)/2;   /* half the max weight of a color */

-        max = 2*hmax;           /* the max weight of a color */

-

-        r1 = rgb[bg[pat].rgb1_max].r;

-        g1 = rgb[bg[pat].rgb1_max].g;

-        b1 = rgb[bg[pat].rgb1_max].b;

-        r2 = rgb[bg[pat].rgb2_max].r;

-        g2 = rgb[bg[pat].rgb2_max].g;

-        b2 = rgb[bg[pat].rgb2_max].b;

-

-        for (row = 0;  row < rpng2_info.height;  ++row) {

-            yidx = (int)(row % bgscale);

-            if (yidx > hmax)

-                yidx = bgscale-1 - yidx;

-            dest = (char *)bg_data + row*bg_rowbytes;

-            for (i = 0;  i < rpng2_info.width;  ++i) {

-                xidx = (int)(i % bgscale);

-                if (xidx > hmax)

-                    xidx = bgscale-1 - xidx;

-                k = xidx + yidx;

-                *dest++ = (k*r1 + (max-k)*r2) / max;

-                *dest++ = (k*g1 + (max-k)*g2) / max;

-                *dest++ = (k*b1 + (max-k)*b2) / max;

-            }

-        }

-

-/*---------------------------------------------------------------------------

-    Radial "starburst" with azimuthal sinusoids; [eventually number of sinu-

-    soids will equal bgscale?].  This one is slow but very cool.  Code con-

-    tributed by Pieter S. van der Meulen (originally in Smalltalk).

-  ---------------------------------------------------------------------------*/

-

-    } else if ((bg[pat].type & 0x07) == 2) {

-        uch ch;

-        int ii, x, y, hw, hh, grayspot;

-        double freq, rotate, saturate, gray, intensity;

-        double angle=0.0, aoffset=0.0, maxDist, dist;

-        double red=0.0, green=0.0, blue=0.0, hue, s, v, f, p, q, t;

-

-        fprintf(stderr, "%s:  computing radial background...",

-          PROGNAME);

-        fflush(stderr);

-

-        hh = (int)(rpng2_info.height / 2);

-        hw = (int)(rpng2_info.width / 2);

-

-        /* variables for radial waves:

-         *   aoffset:  number of degrees to rotate hue [CURRENTLY NOT USED]

-         *   freq:  number of color beams originating from the center

-         *   grayspot:  size of the graying center area (anti-alias)

-         *   rotate:  rotation of the beams as a function of radius

-         *   saturate:  saturation of beams' shape azimuthally

-         */

-        angle = CLIP(angle, 0.0, 360.0);

-        grayspot = CLIP(bg[pat].bg_gray, 1, (hh + hw));

-        freq = MAX((double)bg[pat].bg_freq, 0.0);

-        saturate = (double)bg[pat].bg_bsat * 0.1;

-        rotate = (double)bg[pat].bg_brot * 0.1;

-        gray = 0.0;

-        intensity = 0.0;

-        maxDist = (double)((hw*hw) + (hh*hh));

-

-        for (row = 0;  row < rpng2_info.height;  ++row) {

-            y = (int)(row - hh);

-            dest = (char *)bg_data + row*bg_rowbytes;

-            for (i = 0;  i < rpng2_info.width;  ++i) {

-                x = (int)(i - hw);

-                angle = (x == 0)? PI_2 : atan((double)y / (double)x);

-                gray = (double)MAX(ABS(y), ABS(x)) / grayspot;

-                gray = MIN(1.0, gray);

-                dist = (double)((x*x) + (y*y)) / maxDist;

-                intensity = cos((angle+(rotate*dist*PI)) * freq) *

-                  gray * saturate;

-                intensity = (MAX(MIN(intensity,1.0),-1.0) + 1.0) * 0.5;

-                hue = (angle + PI) * INV_PI_360 + aoffset;

-                s = gray * ((double)(ABS(x)+ABS(y)) / (double)(hw + hh));

-                s = MIN(MAX(s,0.0), 1.0);

-                v = MIN(MAX(intensity,0.0), 1.0);

-

-                if (s == 0.0) {

-                    ch = (uch)(v * 255.0);

-                    *dest++ = ch;

-                    *dest++ = ch;

-                    *dest++ = ch;

-                } else {

-                    if ((hue < 0.0) || (hue >= 360.0))

-                        hue -= (((int)(hue / 360.0)) * 360.0);

-                    hue /= 60.0;

-                    ii = (int)hue;

-                    f = hue - (double)ii;

-                    p = (1.0 - s) * v;

-                    q = (1.0 - (s * f)) * v;

-                    t = (1.0 - (s * (1.0 - f))) * v;

-                    if      (ii == 0) { red = v; green = t; blue = p; }

-                    else if (ii == 1) { red = q; green = v; blue = p; }

-                    else if (ii == 2) { red = p; green = v; blue = t; }

-                    else if (ii == 3) { red = p; green = q; blue = v; }

-                    else if (ii == 4) { red = t; green = p; blue = v; }

-                    else if (ii == 5) { red = v; green = p; blue = q; }

-                    *dest++ = (uch)(red * 255.0);

-                    *dest++ = (uch)(green * 255.0);

-                    *dest++ = (uch)(blue * 255.0);

-                }

-            }

-        }

-        fprintf(stderr, "done.\n");

-        fflush(stderr);

-    }

-

-/*---------------------------------------------------------------------------

-    Blast background image to display buffer before beginning PNG decode.

-  ---------------------------------------------------------------------------*/

-

-    if (depth == 24 || depth == 32) {

-        ulg red, green, blue;

-        int bpp = ximage->bits_per_pixel;

-

-        for (row = 0;  row < rpng2_info.height;  ++row) {

-            src = bg_data + row*bg_rowbytes;

-            dest = ximage->data + row*ximage_rowbytes;

-            if (bpp == 32) {    /* slightly optimized version */

-                for (i = rpng2_info.width;  i > 0;  --i) {

-                    red   = *src++;

-                    green = *src++;

-                    blue  = *src++;

-                    pixel = (red   << RShift) |

-                            (green << GShift) |

-                            (blue  << BShift);

-                    /* recall that we set ximage->byte_order = MSBFirst above */

-                    *dest++ = (char)((pixel >> 24) & 0xff);

-                    *dest++ = (char)((pixel >> 16) & 0xff);

-                    *dest++ = (char)((pixel >>  8) & 0xff);

-                    *dest++ = (char)( pixel        & 0xff);

-                }

-            } else {

-                for (i = rpng2_info.width;  i > 0;  --i) {

-                    red   = *src++;

-                    green = *src++;

-                    blue  = *src++;

-                    pixel = (red   << RShift) |

-                            (green << GShift) |

-                            (blue  << BShift);

-                    /* recall that we set ximage->byte_order = MSBFirst above */

-                    /* GRR BUG?  this assumes bpp == 24 & bits are packed low */

-                    /*           (probably need to use RShift, RMask, etc.) */

-                    *dest++ = (char)((pixel >> 16) & 0xff);

-                    *dest++ = (char)((pixel >>  8) & 0xff);

-                    *dest++ = (char)( pixel        & 0xff);

-                }

-            }

-        }

-

-    } else if (depth == 16) {

-        ush red, green, blue;

-

-        for (row = 0;  row < rpng2_info.height;  ++row) {

-            src = bg_data + row*bg_rowbytes;

-            dest = ximage->data + row*ximage_rowbytes;

-            for (i = rpng2_info.width;  i > 0;  --i) {

-                red   = ((ush)(*src) << 8);  ++src;

-                green = ((ush)(*src) << 8);  ++src;

-                blue  = ((ush)(*src) << 8);  ++src;

-                pixel = ((red   >> RShift) & RMask) |

-                        ((green >> GShift) & GMask) |

-                        ((blue  >> BShift) & BMask);

-                /* recall that we set ximage->byte_order = MSBFirst above */

-                *dest++ = (char)((pixel >>  8) & 0xff);

-                *dest++ = (char)( pixel        & 0xff);

-            }

-        }

-

-    } else /* depth == 8 */ {

-

-        /* GRR:  add 8-bit support */

-

-    }

-

-    XPutImage(display, window, gc, ximage, 0, 0, 0, 0, rpng2_info.width,

-      rpng2_info.height);

-

-    return 0;

-

-} /* end function rpng2_x_load_bg_image() */

-

-

-

-

-

-static void rpng2_x_display_row(ulg row)

-{

-    uch bg_red   = rpng2_info.bg_red;

-    uch bg_green = rpng2_info.bg_green;

-    uch bg_blue  = rpng2_info.bg_blue;

-    uch *src, *src2=NULL;

-    char *dest;

-    uch r, g, b, a;

-    int ximage_rowbytes = ximage->bytes_per_line;

-    ulg i, pixel;

-    static int rows=0, prevpass=(-1);

-    static ulg firstrow;

-

-/*---------------------------------------------------------------------------

-    rows and firstrow simply track how many rows (and which ones) have not

-    yet been displayed; alternatively, we could call XPutImage() for every

-    row and not bother with the records-keeping.

-  ---------------------------------------------------------------------------*/

-

-    Trace((stderr, "beginning rpng2_x_display_row()\n"))

-

-    if (rpng2_info.pass != prevpass) {

-        if (pause_after_pass && rpng2_info.pass > 0) {

-            XEvent e;

-            KeySym k;

-

-            fprintf(stderr,

-              "%s:  end of pass %d of 7; click in image window to continue\n",

-              PROGNAME, prevpass + 1);

-            do

-                XNextEvent(display, &e);

-            while (!QUIT(e,k));

-        }

-        fprintf(stderr, "%s:  pass %d of 7\r", PROGNAME, rpng2_info.pass + 1);

-        fflush(stderr);

-        prevpass = rpng2_info.pass;

-    }

-

-    if (rows == 0)

-        firstrow = row;   /* first row that is not yet displayed */

-

-    ++rows;   /* count of rows received but not yet displayed */

-

-/*---------------------------------------------------------------------------

-    Aside from the use of the rpng2_info struct, the lack of an outer loop

-    (over rows) and moving the XPutImage() call outside the "if (depth)"

-    tests, this routine is identical to rpng_x_display_image() in the non-

-    progressive version of the program.

-  ---------------------------------------------------------------------------*/

-

-    if (depth == 24 || depth == 32) {

-        ulg red, green, blue;

-        int bpp = ximage->bits_per_pixel;

-

-        src = rpng2_info.image_data + row*rpng2_info.rowbytes;

-        if (bg_image)

-            src2 = bg_data + row*bg_rowbytes;

-        dest = ximage->data + row*ximage_rowbytes;

-        if (rpng2_info.channels == 3) {

-            for (i = rpng2_info.width;  i > 0;  --i) {

-                red   = *src++;

-                green = *src++;

-                blue  = *src++;

-                pixel = (red   << RShift) |

-                        (green << GShift) |

-                        (blue  << BShift);

-                /* recall that we set ximage->byte_order = MSBFirst above */

-                if (bpp == 32) {

-                    *dest++ = (char)((pixel >> 24) & 0xff);

-                    *dest++ = (char)((pixel >> 16) & 0xff);

-                    *dest++ = (char)((pixel >>  8) & 0xff);

-                    *dest++ = (char)( pixel        & 0xff);

-                } else {

-                    /* GRR BUG?  this assumes bpp == 24 & bits are packed low */

-                    /*           (probably need to use RShift, RMask, etc.) */

-                    *dest++ = (char)((pixel >> 16) & 0xff);

-                    *dest++ = (char)((pixel >>  8) & 0xff);

-                    *dest++ = (char)( pixel        & 0xff);

-                }

-            }

-        } else /* if (rpng2_info.channels == 4) */ {

-            for (i = rpng2_info.width;  i > 0;  --i) {

-                r = *src++;

-                g = *src++;

-                b = *src++;

-                a = *src++;

-                if (bg_image) {

-                    bg_red   = *src2++;

-                    bg_green = *src2++;

-                    bg_blue  = *src2++;

-                }

-                if (a == 255) {

-                    red   = r;

-                    green = g;

-                    blue  = b;

-                } else if (a == 0) {

-                    red   = bg_red;

-                    green = bg_green;

-                    blue  = bg_blue;

-                } else {

-                    /* this macro (from png.h) composites the foreground

-                     * and background values and puts the result into the

-                     * first argument */

-                    alpha_composite(red,   r, a, bg_red);

-                    alpha_composite(green, g, a, bg_green);

-                    alpha_composite(blue,  b, a, bg_blue);

-                }

-                pixel = (red   << RShift) |

-                        (green << GShift) |

-                        (blue  << BShift);

-                /* recall that we set ximage->byte_order = MSBFirst above */

-                if (bpp == 32) {

-                    *dest++ = (char)((pixel >> 24) & 0xff);

-                    *dest++ = (char)((pixel >> 16) & 0xff);

-                    *dest++ = (char)((pixel >>  8) & 0xff);

-                    *dest++ = (char)( pixel        & 0xff);

-                } else {

-                    /* GRR BUG?  this assumes bpp == 24 & bits are packed low */

-                    /*           (probably need to use RShift, RMask, etc.) */

-                    *dest++ = (char)((pixel >> 16) & 0xff);

-                    *dest++ = (char)((pixel >>  8) & 0xff);

-                    *dest++ = (char)( pixel        & 0xff);

-                }

-            }

-        }

-

-    } else if (depth == 16) {

-        ush red, green, blue;

-

-        src = rpng2_info.row_pointers[row];

-        if (bg_image)

-            src2 = bg_data + row*bg_rowbytes;

-        dest = ximage->data + row*ximage_rowbytes;

-        if (rpng2_info.channels == 3) {

-            for (i = rpng2_info.width;  i > 0;  --i) {

-                red   = ((ush)(*src) << 8);

-                ++src;

-                green = ((ush)(*src) << 8);

-                ++src;

-                blue  = ((ush)(*src) << 8);

-                ++src;

-                pixel = ((red   >> RShift) & RMask) |

-                        ((green >> GShift) & GMask) |

-                        ((blue  >> BShift) & BMask);

-                /* recall that we set ximage->byte_order = MSBFirst above */

-                *dest++ = (char)((pixel >>  8) & 0xff);

-                *dest++ = (char)( pixel        & 0xff);

-            }

-        } else /* if (rpng2_info.channels == 4) */ {

-            for (i = rpng2_info.width;  i > 0;  --i) {

-                r = *src++;

-                g = *src++;

-                b = *src++;

-                a = *src++;

-                if (bg_image) {

-                    bg_red   = *src2++;

-                    bg_green = *src2++;

-                    bg_blue  = *src2++;

-                }

-                if (a == 255) {

-                    red   = ((ush)r << 8);

-                    green = ((ush)g << 8);

-                    blue  = ((ush)b << 8);

-                } else if (a == 0) {

-                    red   = ((ush)bg_red   << 8);

-                    green = ((ush)bg_green << 8);

-                    blue  = ((ush)bg_blue  << 8);

-                } else {

-                    /* this macro (from png.h) composites the foreground

-                     * and background values and puts the result back into

-                     * the first argument (== fg byte here:  safe) */

-                    alpha_composite(r, r, a, bg_red);

-                    alpha_composite(g, g, a, bg_green);

-                    alpha_composite(b, b, a, bg_blue);

-                    red   = ((ush)r << 8);

-                    green = ((ush)g << 8);

-                    blue  = ((ush)b << 8);

-                }

-                pixel = ((red   >> RShift) & RMask) |

-                        ((green >> GShift) & GMask) |

-                        ((blue  >> BShift) & BMask);

-                /* recall that we set ximage->byte_order = MSBFirst above */

-                *dest++ = (char)((pixel >>  8) & 0xff);

-                *dest++ = (char)( pixel        & 0xff);

-            }

-        }

-

-    } else /* depth == 8 */ {

-

-        /* GRR:  add 8-bit support */

-

-    }

-

-

-/*---------------------------------------------------------------------------

-    Display after every 16 rows or when on one of last two rows.  (Region

-    may include previously displayed lines due to interlacing--i.e., not

-    contiguous.  Also, second-to-last row is final one in interlaced images

-    with odd number of rows.)  For demos, flush (and delay) after every 16th

-    row so "sparse" passes don't go twice as fast.

-  ---------------------------------------------------------------------------*/

-

-    if (demo_timing && (row - firstrow >= 16 || row >= rpng2_info.height-2)) {

-        XPutImage(display, window, gc, ximage, 0, (int)firstrow, 0,

-          (int)firstrow, rpng2_info.width, row - firstrow + 1);

-        XFlush(display);

-        rows = 0;

-        usleep(usleep_duration);

-    } else

-    if (!demo_timing && ((rows & 0xf) == 0 || row >= rpng2_info.height-2)) {

-        XPutImage(display, window, gc, ximage, 0, (int)firstrow, 0,

-          (int)firstrow, rpng2_info.width, row - firstrow + 1);

-        XFlush(display);

-        rows = 0;

-    }

-

-}

-

-

-

-

-

-static void rpng2_x_finish_display(void)

-{

-    Trace((stderr, "beginning rpng2_x_finish_display()\n"))

-

-    /* last row has already been displayed by rpng2_x_display_row(), so we

-     * have nothing to do here except set a flag and let the user know that

-     * the image is done */

-

-    rpng2_info.state = kDone;

-    printf(

-      "Done.  Press Q, Esc or mouse button 1 (within image window) to quit.\n");

-    fflush(stdout);

-}

-

-

-

-

-

-static void rpng2_x_redisplay_image(ulg startcol, ulg startrow,

-                                    ulg width, ulg height)

-{

-    uch bg_red   = rpng2_info.bg_red;

-    uch bg_green = rpng2_info.bg_green;

-    uch bg_blue  = rpng2_info.bg_blue;

-    uch *src, *src2=NULL;

-    char *dest;

-    uch r, g, b, a;

-    ulg i, row, lastrow = 0;

-    ulg pixel;

-    int ximage_rowbytes = ximage->bytes_per_line;

-

-

-    Trace((stderr, "beginning display loop (image_channels == %d)\n",

-      rpng2_info.channels))

-    Trace((stderr, "   (width = %ld, rowbytes = %d, ximage_rowbytes = %d)\n",

-      rpng2_info.width, rpng2_info.rowbytes, ximage_rowbytes))

-    Trace((stderr, "   (bpp = %d)\n", ximage->bits_per_pixel))

-    Trace((stderr, "   (byte_order = %s)\n", ximage->byte_order == MSBFirst?

-      "MSBFirst" : (ximage->byte_order == LSBFirst? "LSBFirst" : "unknown")))

-

-/*---------------------------------------------------------------------------

-    Aside from the use of the rpng2_info struct and of src2 (for background

-    image), this routine is identical to rpng_x_display_image() in the non-

-    progressive version of the program--for the simple reason that redisplay

-    of the image against a new background happens after the image is fully

-    decoded and therefore is, by definition, non-progressive.

-  ---------------------------------------------------------------------------*/

-

-    if (depth == 24 || depth == 32) {

-        ulg red, green, blue;

-        int bpp = ximage->bits_per_pixel;

-

-        for (lastrow = row = startrow;  row < startrow+height;  ++row) {

-            src = rpng2_info.image_data + row*rpng2_info.rowbytes;

-            if (bg_image)

-                src2 = bg_data + row*bg_rowbytes;

-            dest = ximage->data + row*ximage_rowbytes;

-            if (rpng2_info.channels == 3) {

-                for (i = rpng2_info.width;  i > 0;  --i) {

-                    red   = *src++;

-                    green = *src++;

-                    blue  = *src++;

-#ifdef NO_24BIT_MASKS

-                    pixel = (red   << RShift) |

-                            (green << GShift) |

-                            (blue  << BShift);

-                    /* recall that we set ximage->byte_order = MSBFirst above */

-                    if (bpp == 32) {

-                        *dest++ = (char)((pixel >> 24) & 0xff);

-                        *dest++ = (char)((pixel >> 16) & 0xff);

-                        *dest++ = (char)((pixel >>  8) & 0xff);

-                        *dest++ = (char)( pixel        & 0xff);

-                    } else {

-                        /* this assumes bpp == 24 & bits are packed low */

-                        /* (probably need to use RShift, RMask, etc.) */

-                        *dest++ = (char)((pixel >> 16) & 0xff);

-                        *dest++ = (char)((pixel >>  8) & 0xff);

-                        *dest++ = (char)( pixel        & 0xff);

-                    }

-#else

-                    red   = (RShift < 0)? red   << (-RShift) : red   >> RShift;

-                    green = (GShift < 0)? green << (-GShift) : green >> GShift;

-                    blue  = (BShift < 0)? blue  << (-BShift) : blue  >> BShift;

-                    pixel = (red & RMask) | (green & GMask) | (blue & BMask);

-                    /* recall that we set ximage->byte_order = MSBFirst above */

-                    if (bpp == 32) {

-                        *dest++ = (char)((pixel >> 24) & 0xff);

-                        *dest++ = (char)((pixel >> 16) & 0xff);

-                        *dest++ = (char)((pixel >>  8) & 0xff);

-                        *dest++ = (char)( pixel        & 0xff);

-                    } else {

-                        /* GRR BUG */

-                        /* this assumes bpp == 24 & bits are packed low */

-                        /* (probably need to use RShift/RMask/etc. here, too) */

-                        *dest++ = (char)((pixel >> 16) & 0xff);

-                        *dest++ = (char)((pixel >>  8) & 0xff);

-                        *dest++ = (char)( pixel        & 0xff);

-                    }

-#endif

-                }

-

-            } else /* if (rpng2_info.channels == 4) */ {

-                for (i = rpng2_info.width;  i > 0;  --i) {

-                    r = *src++;

-                    g = *src++;

-                    b = *src++;

-                    a = *src++;

-                    if (bg_image) {

-                        bg_red   = *src2++;

-                        bg_green = *src2++;

-                        bg_blue  = *src2++;

-                    }

-                    if (a == 255) {

-                        red   = r;

-                        green = g;

-                        blue  = b;

-                    } else if (a == 0) {

-                        red   = bg_red;

-                        green = bg_green;

-                        blue  = bg_blue;

-                    } else {

-                        /* this macro (from png.h) composites the foreground

-                         * and background values and puts the result into the

-                         * first argument */

-                        alpha_composite(red,   r, a, bg_red);

-                        alpha_composite(green, g, a, bg_green);

-                        alpha_composite(blue,  b, a, bg_blue);

-                    }

-#ifdef NO_24BIT_MASKS

-                    pixel = (red   << RShift) |

-                            (green << GShift) |

-                            (blue  << BShift);

-                    /* recall that we set ximage->byte_order = MSBFirst above */

-                    if (bpp == 32) {

-                        *dest++ = (char)((pixel >> 24) & 0xff);

-                        *dest++ = (char)((pixel >> 16) & 0xff);

-                        *dest++ = (char)((pixel >>  8) & 0xff);

-                        *dest++ = (char)( pixel        & 0xff);

-                    } else {

-                        /* this assumes bpp == 24 & bits are packed low */

-                        /* (probably need to use RShift, RMask, etc.) */

-                        *dest++ = (char)((pixel >> 16) & 0xff);

-                        *dest++ = (char)((pixel >>  8) & 0xff);

-                        *dest++ = (char)( pixel        & 0xff);

-                    }

-#else

-                    red   = (RShift < 0)? red   << (-RShift) : red   >> RShift;

-                    green = (GShift < 0)? green << (-GShift) : green >> GShift;

-                    blue  = (BShift < 0)? blue  << (-BShift) : blue  >> BShift;

-                    pixel = (red & RMask) | (green & GMask) | (blue & BMask);

-                    /* recall that we set ximage->byte_order = MSBFirst above */

-                    if (bpp == 32) {

-                        *dest++ = (char)((pixel >> 24) & 0xff);

-                        *dest++ = (char)((pixel >> 16) & 0xff);

-                        *dest++ = (char)((pixel >>  8) & 0xff);

-                        *dest++ = (char)( pixel        & 0xff);

-                    } else {

-                        /* GRR BUG */

-                        /* this assumes bpp == 24 & bits are packed low */

-                        /* (probably need to use RShift/RMask/etc. here, too) */

-                        *dest++ = (char)((pixel >> 16) & 0xff);

-                        *dest++ = (char)((pixel >>  8) & 0xff);

-                        *dest++ = (char)( pixel        & 0xff);

-                    }

-#endif

-                }

-            }

-            /* display after every 16 lines */

-            if (((row+1) & 0xf) == 0) {

-                XPutImage(display, window, gc, ximage, 0, (int)lastrow, 0,

-                  (int)lastrow, rpng2_info.width, 16);

-                XFlush(display);

-                lastrow = row + 1;

-            }

-        }

-

-    } else if (depth == 16) {

-        ush red, green, blue;

-

-        for (lastrow = row = startrow;  row < startrow+height;  ++row) {

-            src = rpng2_info.row_pointers[row];

-            if (bg_image)

-                src2 = bg_data + row*bg_rowbytes;

-            dest = ximage->data + row*ximage_rowbytes;

-            if (rpng2_info.channels == 3) {

-                for (i = rpng2_info.width;  i > 0;  --i) {

-                    red   = ((ush)(*src) << 8);

-                    ++src;

-                    green = ((ush)(*src) << 8);

-                    ++src;

-                    blue  = ((ush)(*src) << 8);

-                    ++src;

-                    pixel = ((red   >> RShift) & RMask) |

-                            ((green >> GShift) & GMask) |

-                            ((blue  >> BShift) & BMask);

-                    /* recall that we set ximage->byte_order = MSBFirst above */

-                    *dest++ = (char)((pixel >>  8) & 0xff);

-                    *dest++ = (char)( pixel        & 0xff);

-                }

-            } else /* if (rpng2_info.channels == 4) */ {

-                for (i = rpng2_info.width;  i > 0;  --i) {

-                    r = *src++;

-                    g = *src++;

-                    b = *src++;

-                    a = *src++;

-                    if (bg_image) {

-                        bg_red   = *src2++;

-                        bg_green = *src2++;

-                        bg_blue  = *src2++;

-                    }

-                    if (a == 255) {

-                        red   = ((ush)r << 8);

-                        green = ((ush)g << 8);

-                        blue  = ((ush)b << 8);

-                    } else if (a == 0) {

-                        red   = ((ush)bg_red   << 8);

-                        green = ((ush)bg_green << 8);

-                        blue  = ((ush)bg_blue  << 8);

-                    } else {

-                        /* this macro (from png.h) composites the foreground

-                         * and background values and puts the result back into

-                         * the first argument (== fg byte here:  safe) */

-                        alpha_composite(r, r, a, bg_red);

-                        alpha_composite(g, g, a, bg_green);

-                        alpha_composite(b, b, a, bg_blue);

-                        red   = ((ush)r << 8);

-                        green = ((ush)g << 8);

-                        blue  = ((ush)b << 8);

-                    }

-                    pixel = ((red   >> RShift) & RMask) |

-                            ((green >> GShift) & GMask) |

-                            ((blue  >> BShift) & BMask);

-                    /* recall that we set ximage->byte_order = MSBFirst above */

-                    *dest++ = (char)((pixel >>  8) & 0xff);

-                    *dest++ = (char)( pixel        & 0xff);

-                }

-            }

-            /* display after every 16 lines */

-            if (((row+1) & 0xf) == 0) {

-                XPutImage(display, window, gc, ximage, 0, (int)lastrow, 0,

-                  (int)lastrow, rpng2_info.width, 16);

-                XFlush(display);

-                lastrow = row + 1;

-            }

-        }

-

-    } else /* depth == 8 */ {

-

-        /* GRR:  add 8-bit support */

-

-    }

-

-    Trace((stderr, "calling final XPutImage()\n"))

-    if (lastrow < startrow+height) {

-        XPutImage(display, window, gc, ximage, 0, (int)lastrow, 0,

-          (int)lastrow, rpng2_info.width, rpng2_info.height-lastrow);

-        XFlush(display);

-    }

-

-} /* end function rpng2_x_redisplay_image() */

-

-

-

-

-

-#ifdef FEATURE_LOOP

-

-static void rpng2_x_reload_bg_image(void)

-{

-    char *dest;

-    uch r1, r2, g1, g2, b1, b2;

-    uch r1_inv, r2_inv, g1_inv, g2_inv, b1_inv, b2_inv;

-    int k, hmax, max;

-    int xidx, yidx, yidx_max;

-    int even_odd_vert, even_odd_horiz, even_odd;

-    int invert_gradient2 = (bg[pat].type & 0x08);

-    int invert_column;

-    ulg i, row;

-

-

-    bgscale = (pat == 0)? 8 : bgscale_default;

-    yidx_max = bgscale - 1;

-

-/*---------------------------------------------------------------------------

-    Vertical gradients (ramps) in NxN squares, alternating direction and

-    colors (N == bgscale).

-  ---------------------------------------------------------------------------*/

-

-    if ((bg[pat].type & 0x07) == 0) {

-        uch r1_min  = rgb[bg[pat].rgb1_min].r;

-        uch g1_min  = rgb[bg[pat].rgb1_min].g;

-        uch b1_min  = rgb[bg[pat].rgb1_min].b;

-        uch r2_min  = rgb[bg[pat].rgb2_min].r;

-        uch g2_min  = rgb[bg[pat].rgb2_min].g;

-        uch b2_min  = rgb[bg[pat].rgb2_min].b;

-        int r1_diff = rgb[bg[pat].rgb1_max].r - r1_min;

-        int g1_diff = rgb[bg[pat].rgb1_max].g - g1_min;

-        int b1_diff = rgb[bg[pat].rgb1_max].b - b1_min;

-        int r2_diff = rgb[bg[pat].rgb2_max].r - r2_min;

-        int g2_diff = rgb[bg[pat].rgb2_max].g - g2_min;

-        int b2_diff = rgb[bg[pat].rgb2_max].b - b2_min;

-

-        for (row = 0;  row < rpng2_info.height;  ++row) {

-            yidx = (int)(row % bgscale);

-            even_odd_vert = (int)((row / bgscale) & 1);

-

-            r1 = r1_min + (r1_diff * yidx) / yidx_max;

-            g1 = g1_min + (g1_diff * yidx) / yidx_max;

-            b1 = b1_min + (b1_diff * yidx) / yidx_max;

-            r1_inv = r1_min + (r1_diff * (yidx_max-yidx)) / yidx_max;

-            g1_inv = g1_min + (g1_diff * (yidx_max-yidx)) / yidx_max;

-            b1_inv = b1_min + (b1_diff * (yidx_max-yidx)) / yidx_max;

-

-            r2 = r2_min + (r2_diff * yidx) / yidx_max;

-            g2 = g2_min + (g2_diff * yidx) / yidx_max;

-            b2 = b2_min + (b2_diff * yidx) / yidx_max;

-            r2_inv = r2_min + (r2_diff * (yidx_max-yidx)) / yidx_max;

-            g2_inv = g2_min + (g2_diff * (yidx_max-yidx)) / yidx_max;

-            b2_inv = b2_min + (b2_diff * (yidx_max-yidx)) / yidx_max;

-

-            dest = (char *)bg_data + row*bg_rowbytes;

-            for (i = 0;  i < rpng2_info.width;  ++i) {

-                even_odd_horiz = (int)((i / bgscale) & 1);

-                even_odd = even_odd_vert ^ even_odd_horiz;

-                invert_column =

-                  (even_odd_horiz && (bg[pat].type & 0x10));

-                if (even_odd == 0) {        /* gradient #1 */

-                    if (invert_column) {

-                        *dest++ = r1_inv;

-                        *dest++ = g1_inv;

-                        *dest++ = b1_inv;

-                    } else {

-                        *dest++ = r1;

-                        *dest++ = g1;

-                        *dest++ = b1;

-                    }

-                } else {                    /* gradient #2 */

-                    if ((invert_column && invert_gradient2) ||

-                        (!invert_column && !invert_gradient2))

-                    {

-                        *dest++ = r2;       /* not inverted or */

-                        *dest++ = g2;       /*  doubly inverted */

-                        *dest++ = b2;

-                    } else {

-                        *dest++ = r2_inv;

-                        *dest++ = g2_inv;   /* singly inverted */

-                        *dest++ = b2_inv;

-                    }

-                }

-            }

-        }

-

-/*---------------------------------------------------------------------------

-    Soft gradient-diamonds with scale = bgscale.  Code contributed by Adam

-    M. Costello.

-  ---------------------------------------------------------------------------*/

-

-    } else if ((bg[pat].type & 0x07) == 1) {

-

-        hmax = (bgscale-1)/2;   /* half the max weight of a color */

-        max = 2*hmax;           /* the max weight of a color */

-

-        r1 = rgb[bg[pat].rgb1_max].r;

-        g1 = rgb[bg[pat].rgb1_max].g;

-        b1 = rgb[bg[pat].rgb1_max].b;

-        r2 = rgb[bg[pat].rgb2_max].r;

-        g2 = rgb[bg[pat].rgb2_max].g;

-        b2 = rgb[bg[pat].rgb2_max].b;

-

-        for (row = 0;  row < rpng2_info.height;  ++row) {

-            yidx = (int)(row % bgscale);

-            if (yidx > hmax)

-                yidx = bgscale-1 - yidx;

-            dest = (char *)bg_data + row*bg_rowbytes;

-            for (i = 0;  i < rpng2_info.width;  ++i) {

-                xidx = (int)(i % bgscale);

-                if (xidx > hmax)

-                    xidx = bgscale-1 - xidx;

-                k = xidx + yidx;

-                *dest++ = (k*r1 + (max-k)*r2) / max;

-                *dest++ = (k*g1 + (max-k)*g2) / max;

-                *dest++ = (k*b1 + (max-k)*b2) / max;

-            }

-        }

-

-/*---------------------------------------------------------------------------

-    Radial "starburst" with azimuthal sinusoids; [eventually number of sinu-

-    soids will equal bgscale?].  This one is slow but very cool.  Code con-

-    tributed by Pieter S. van der Meulen (originally in Smalltalk).

-  ---------------------------------------------------------------------------*/

-

-    } else if ((bg[pat].type & 0x07) == 2) {

-        uch ch;

-        int ii, x, y, hw, hh, grayspot;

-        double freq, rotate, saturate, gray, intensity;

-        double angle=0.0, aoffset=0.0, maxDist, dist;

-        double red=0.0, green=0.0, blue=0.0, hue, s, v, f, p, q, t;

-

-        hh = (int)(rpng2_info.height / 2);

-        hw = (int)(rpng2_info.width / 2);

-

-        /* variables for radial waves:

-         *   aoffset:  number of degrees to rotate hue [CURRENTLY NOT USED]

-         *   freq:  number of color beams originating from the center

-         *   grayspot:  size of the graying center area (anti-alias)

-         *   rotate:  rotation of the beams as a function of radius

-         *   saturate:  saturation of beams' shape azimuthally

-         */

-        angle = CLIP(angle, 0.0, 360.0);

-        grayspot = CLIP(bg[pat].bg_gray, 1, (hh + hw));

-        freq = MAX((double)bg[pat].bg_freq, 0.0);

-        saturate = (double)bg[pat].bg_bsat * 0.1;

-        rotate = (double)bg[pat].bg_brot * 0.1;

-        gray = 0.0;

-        intensity = 0.0;

-        maxDist = (double)((hw*hw) + (hh*hh));

-

-        for (row = 0;  row < rpng2_info.height;  ++row) {

-            y = (int)(row - hh);

-            dest = (char *)bg_data + row*bg_rowbytes;

-            for (i = 0;  i < rpng2_info.width;  ++i) {

-                x = (int)(i - hw);

-                angle = (x == 0)? PI_2 : atan((double)y / (double)x);

-                gray = (double)MAX(ABS(y), ABS(x)) / grayspot;

-                gray = MIN(1.0, gray);

-                dist = (double)((x*x) + (y*y)) / maxDist;

-                intensity = cos((angle+(rotate*dist*PI)) * freq) *

-                  gray * saturate;

-                intensity = (MAX(MIN(intensity,1.0),-1.0) + 1.0) * 0.5;

-                hue = (angle + PI) * INV_PI_360 + aoffset;

-                s = gray * ((double)(ABS(x)+ABS(y)) / (double)(hw + hh));

-                s = MIN(MAX(s,0.0), 1.0);

-                v = MIN(MAX(intensity,0.0), 1.0);

-

-                if (s == 0.0) {

-                    ch = (uch)(v * 255.0);

-                    *dest++ = ch;

-                    *dest++ = ch;

-                    *dest++ = ch;

-                } else {

-                    if ((hue < 0.0) || (hue >= 360.0))

-                        hue -= (((int)(hue / 360.0)) * 360.0);

-                    hue /= 60.0;

-                    ii = (int)hue;

-                    f = hue - (double)ii;

-                    p = (1.0 - s) * v;

-                    q = (1.0 - (s * f)) * v;

-                    t = (1.0 - (s * (1.0 - f))) * v;

-                    if      (ii == 0) { red = v; green = t; blue = p; }

-                    else if (ii == 1) { red = q; green = v; blue = p; }

-                    else if (ii == 2) { red = p; green = v; blue = t; }

-                    else if (ii == 3) { red = p; green = q; blue = v; }

-                    else if (ii == 4) { red = t; green = p; blue = v; }

-                    else if (ii == 5) { red = v; green = p; blue = q; }

-                    *dest++ = (uch)(red * 255.0);

-                    *dest++ = (uch)(green * 255.0);

-                    *dest++ = (uch)(blue * 255.0);

-                }

-            }

-        }

-    }

-

-} /* end function rpng2_x_reload_bg_image() */

-

-

-

-

-

-static int is_number(char *p)

-{

-    while (*p) {

-        if (!isdigit(*p))

-            return FALSE;

-        ++p;

-    }

-    return TRUE;

-}

-

-#endif /* FEATURE_LOOP */

-

-

-

-

-

-static void rpng2_x_cleanup(void)

-{

-    if (bg_image && bg_data) {

-        free(bg_data);

-        bg_data = NULL;

-    }

-

-    if (rpng2_info.image_data) {

-        free(rpng2_info.image_data);

-        rpng2_info.image_data = NULL;

-    }

-

-    if (rpng2_info.row_pointers) {

-        free(rpng2_info.row_pointers);

-        rpng2_info.row_pointers = NULL;

-    }

-

-    if (ximage) {

-        if (ximage->data) {

-            free(ximage->data);           /* we allocated it, so we free it */

-            ximage->data = (char *)NULL;  /*  instead of XDestroyImage() */

-        }

-        XDestroyImage(ximage);

-        ximage = NULL;

-    }

-

-    if (have_gc)

-        XFreeGC(display, gc);

-

-    if (have_window)

-        XDestroyWindow(display, window);

-

-    if (have_colormap)

-        XFreeColormap(display, colormap);

-

-    if (have_nondefault_visual)

-        XFree(visual_list);

-}

-

-

-

-

-

-static int rpng2_x_msb(ulg u32val)

-{

-    int i;

-

-    for (i = 31;  i >= 0;  --i) {

-        if (u32val & 0x80000000L)

-            break;

-        u32val <<= 1;

-    }

-    return i;

-}

+/*---------------------------------------------------------------------------
+
+   rpng2 - progressive-model PNG display program                  rpng2-x.c
+
+   This program decodes and displays PNG files progressively, as if it were
+   a web browser (though the front end is only set up to read from files).
+   It supports gamma correction, user-specified background colors, and user-
+   specified background patterns (for transparent images).  This version is
+   for the X Window System (tested by the author under Unix and by Martin
+   Zinser under OpenVMS; may work under OS/2 with a little tweaking).
+
+   Thanks to Adam Costello and Pieter S. van der Meulen for the "diamond"
+   and "radial waves" patterns, respectively.
+
+   to do (someday, maybe):
+    - fix expose/redraw code:  don't draw entire row if only part exposed
+    - 8-bit (colormapped) X support
+    - finish resizable checkerboard-gradient (sizes 4-128?)
+    - use %.1023s to simplify truncation of title-bar string?
+
+  ---------------------------------------------------------------------------
+
+   Changelog:
+    - 1.01:  initial public release
+    - 1.02:  modified to allow abbreviated options; fixed char/uchar mismatch
+    - 1.10:  added support for non-default visuals; fixed X pixel-conversion
+    - 1.11:  added -usleep option for demos; fixed command-line parsing bug
+    - 1.12:  added -pause option for demos and testing
+    - 1.20:  added runtime MMX-enabling/disabling and new -mmx* options
+    - 1.21:  fixed some small X memory leaks (thanks to François Petitjean)
+    - 1.22:  fixed XFreeGC() crash bug (thanks to Patrick Welche)
+    - 1.23:  added -bgpat 0 mode (std white/gray checkerboard, 8x8 squares)
+    - 1.30:  added -loop option for -bgpat (ifdef FEATURE_LOOP); fixed bpp =
+              24; added support for X resources (thanks to Gerhard Niklasch)
+    - 1.31:  added code to skip unused chunks (thanks to Glenn Randers-Pehrson)
+    - 1.32:  added AMD64/EM64T support (__x86_64__); added basic expose/redraw
+              handling
+    - 2.00:  dual-licensed (added GNU GPL)
+    - 2.01:  fixed 64-bit typo in readpng2.c; fixed -pause usage description
+    - 2.02:  fixed improper display of usage screen on PNG error(s); fixed
+              unexpected-EOF and file-read-error cases; fixed Trace() cut-and-
+              paste bugs
+    - 2.03:  deleted runtime MMX-enabling/disabling and obsolete -mmx* options
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-2008 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      The contents of this file are DUAL-LICENSED.  You may modify and/or
+      redistribute this software according to the terms of one of the
+      following two licenses (at your option):
+
+
+      LICENSE 1 ("BSD-like with advertising clause"):
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+
+      LICENSE 2 (GNU GPL v2 or later):
+
+      This program is free software; you can redistribute it and/or modify
+      it under the terms of the GNU General Public License as published by
+      the Free Software Foundation; either version 2 of the License, or
+      (at your option) any later version.
+
+      This program is distributed in the hope that it will be useful,
+      but WITHOUT ANY WARRANTY; without even the implied warranty of
+      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+      GNU General Public License for more details.
+
+      You should have received a copy of the GNU General Public License
+      along with this program; if not, write to the Free Software Foundation,
+      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+  ---------------------------------------------------------------------------*/
+
+#define PROGNAME  "rpng2-x"
+#define LONGNAME  "Progressive PNG Viewer for X"
+#define VERSION   "2.03 of 25 February 2010"
+#define RESNAME   "rpng2"       /* our X resource application name */
+#define RESCLASS  "Rpng"       /* our X resource class name */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <ctype.h>
+#include <string.h>
+#include <setjmp.h>       /* for jmpbuf declaration in readpng2.h */
+#include <time.h>
+#include <math.h>         /* only for PvdM background code */
+#include <X11/Xlib.h>
+#include <X11/Xutil.h>
+#include <X11/Xos.h>
+#include <X11/keysym.h>   /* defines XK_* macros */
+
+#ifdef VMS
+#  include <unistd.h>
+#endif
+
+/* all for PvdM background code: */
+#ifndef PI
+#  define PI             3.141592653589793238
+#endif
+#define PI_2             (PI*0.5)
+#define INV_PI_360       (360.0 / PI)
+#define MAX(a,b)         (a>b?a:b)
+#define MIN(a,b)         (a<b?a:b)
+#define CLIP(a,min,max)  MAX(min,MIN((a),max))
+#define ABS(a)           ((a)<0?-(a):(a))
+#define CLIP8P(c)        MAX(0,(MIN((c),255)))   /* 8-bit pos. integer (uch) */
+#define ROUNDF(f)        ((int)(f + 0.5))
+
+#define QUIT(e,k) ((e.type == ButtonPress && e.xbutton.button == Button1) ||  \
+                  (e.type == KeyPress &&   /*  v--- or 1 for shifted keys */  \
+                  ((k = XLookupKeysym(&e.xkey, 0)) == XK_q || k == XK_Escape)))
+
+#define NO_24BIT_MASKS /* undef case not fully written--only for redisplay() */
+
+#define rgb1_max   bg_freq
+#define rgb1_min   bg_gray
+#define rgb2_max   bg_bsat
+#define rgb2_min   bg_brot
+
+/* #define DEBUG */     /* this enables the Trace() macros */
+
+#include "readpng2.h"   /* typedefs, common macros, readpng2 prototypes */
+
+
+/* could just include png.h, but this macro is the only thing we need
+ * (name and typedefs changed to local versions); note that side effects
+ * only happen with alpha (which could easily be avoided with
+ * "ush acopy = (alpha);") */
+
+#define alpha_composite(composite, fg, alpha, bg) {               \
+    ush temp = ((ush)(fg)*(ush)(alpha) +                          \
+                (ush)(bg)*(ush)(255 - (ush)(alpha)) + (ush)128);  \
+    (composite) = (uch)((temp + (temp >> 8)) >> 8);               \
+}
+
+
+#define INBUFSIZE 4096   /* with pseudo-timing on (1 sec delay/block), this
+                          *  block size corresponds roughly to a download
+                          *  speed 10% faster than theoretical 33.6K maximum
+                          *  (assuming 8 data bits, 1 stop bit and no other
+                          *  overhead) */
+
+/* local prototypes */
+static void rpng2_x_init (void);
+static int  rpng2_x_create_window (void);
+static int  rpng2_x_load_bg_image (void);
+static void rpng2_x_display_row (ulg row);
+static void rpng2_x_finish_display (void);
+static void rpng2_x_redisplay_image (ulg startcol, ulg startrow,
+                                     ulg width, ulg height);
+#ifdef FEATURE_LOOP
+static void rpng2_x_reload_bg_image (void);
+static int  is_number (char *p);
+#endif
+static void rpng2_x_cleanup (void);
+static int  rpng2_x_msb (ulg u32val);
+
+
+static char titlebar[1024], *window_name = titlebar;
+static char *appname = LONGNAME;
+static char *icon_name = PROGNAME;
+static char *res_name = RESNAME;
+static char *res_class = RESCLASS;
+static char *filename;
+static FILE *infile;
+
+static mainprog_info rpng2_info;
+
+static uch inbuf[INBUFSIZE];
+static int incount;
+
+static int pat = 6;        /* must be less than num_bgpat */
+static int bg_image = 0;
+static int bgscale, bgscale_default = 16;
+static ulg bg_rowbytes;
+static uch *bg_data;
+
+int pause_after_pass = FALSE;
+int demo_timing = FALSE;
+ulg usleep_duration = 0L;
+
+static struct rgb_color {
+    uch r, g, b;
+} rgb[] = {
+    {  0,   0,   0},    /*  0:  black */
+    {255, 255, 255},    /*  1:  white */
+    {173, 132,  57},    /*  2:  tan */
+    { 64, 132,   0},    /*  3:  medium green */
+    {189, 117,   1},    /*  4:  gold */
+    {253, 249,   1},    /*  5:  yellow */
+    {  0,   0, 255},    /*  6:  blue */
+    {  0,   0, 120},    /*  7:  medium blue */
+    {255,   0, 255},    /*  8:  magenta */
+    { 64,   0,  64},    /*  9:  dark magenta */
+    {255,   0,   0},    /* 10:  red */
+    { 64,   0,   0},    /* 11:  dark red */
+    {255, 127,   0},    /* 12:  orange */
+    {192,  96,   0},    /* 13:  darker orange */
+    { 24,  60,   0},    /* 14:  dark green-yellow */
+    { 85, 125, 200},    /* 15:  ice blue */
+    {192, 192, 192}     /* 16:  Netscape/Mosaic gray */
+};
+/* not used for now, but should be for error-checking:
+static int num_rgb = sizeof(rgb) / sizeof(struct rgb_color);
+ */
+
+/*
+    This whole struct is a fairly cheesy way to keep the number of
+    command-line options to a minimum.  The radial-waves background
+    type is a particularly poor fit to the integer elements of the
+    struct...but a few macros and a little fixed-point math will do
+    wonders for ya.
+
+    type bits:
+       F E D C B A 9 8 7 6 5 4 3 2 1 0
+                             | | | | |
+                             | | +-+-+-- 0 = sharp-edged checkerboard
+                             | |         1 = soft diamonds
+                             | |         2 = radial waves
+                             | |       3-7 = undefined
+                             | +-- gradient #2 inverted?
+                             +-- alternating columns inverted?
+ */
+static struct background_pattern {
+    ush type;
+    int rgb1_max, rgb1_min;     /* or bg_freq, bg_gray */
+    int rgb2_max, rgb2_min;     /* or bg_bsat, bg_brot (both scaled by 10)*/
+} bg[] = {
+    {0,     1,1, 16,16},        /* checkered:  white vs. light gray (basic) */
+    {0+8,   2,0,  1,15},        /* checkered:  tan/black vs. white/ice blue */
+    {0+24,  2,0,  1,0},         /* checkered:  tan/black vs. white/black */
+    {0+8,   4,5,  0,2},         /* checkered:  gold/yellow vs. black/tan */
+    {0+8,   4,5,  0,6},         /* checkered:  gold/yellow vs. black/blue */
+    {0,     7,0,  8,9},         /* checkered:  deep blue/black vs. magenta */
+    {0+8,  13,0,  5,14},        /* checkered:  orange/black vs. yellow */
+    {0+8,  12,0, 10,11},        /* checkered:  orange/black vs. red */
+    {1,     7,0,  8,0},         /* diamonds:  deep blue/black vs. magenta */
+    {1,    12,0, 11,0},         /* diamonds:  orange vs. dark red */
+    {1,    10,0,  7,0},         /* diamonds:  red vs. medium blue */
+    {1,     4,0,  5,0},         /* diamonds:  gold vs. yellow */
+    {1,     3,0,  0,0},         /* diamonds:  medium green vs. black */
+    {2,    16, 100,  20,   0},  /* radial:  ~hard radial color-beams */
+    {2,    18, 100,  10,   2},  /* radial:  soft, curved radial color-beams */
+    {2,    16, 256, 100, 250},  /* radial:  very tight spiral */
+    {2, 10000, 256,  11,   0}   /* radial:  dipole-moire' (almost fractal) */
+};
+static int num_bgpat = sizeof(bg) / sizeof(struct background_pattern);
+
+
+/* X-specific variables */
+static char *displayname;
+static XImage *ximage;
+static Display *display;
+static int depth;
+static Visual *visual;
+static XVisualInfo *visual_list;
+static int RShift, GShift, BShift;
+static ulg RMask, GMask, BMask;
+static Window window;
+static GC gc;
+static Colormap colormap;
+
+static int have_nondefault_visual = FALSE;
+static int have_colormap = FALSE;
+static int have_window = FALSE;
+static int have_gc = FALSE;
+
+
+
+
+int main(int argc, char **argv)
+{
+#ifdef sgi
+    char tmpline[80];
+#endif
+    char *p, *bgstr = NULL;
+    int rc, alen, flen;
+    int error = 0;
+    int timing = FALSE;
+    int have_bg = FALSE;
+#ifdef FEATURE_LOOP
+    int loop = FALSE;
+    long loop_interval = -1;            /* seconds (100,000 max) */
+#endif
+    double LUT_exponent;                /* just the lookup table */
+    double CRT_exponent = 2.2;          /* just the monitor */
+    double default_display_exponent;    /* whole display system */
+    XEvent e;
+    KeySym k;
+
+
+    /* First initialize a few things, just to be sure--memset takes care of
+     * default background color (black), booleans (FALSE), pointers (NULL),
+     * etc. */
+
+    displayname = (char *)NULL;
+    filename = (char *)NULL;
+    memset(&rpng2_info, 0, sizeof(mainprog_info));
+
+
+    /* Set the default value for our display-system exponent, i.e., the
+     * product of the CRT exponent and the exponent corresponding to
+     * the frame-buffer's lookup table (LUT), if any.  This is not an
+     * exhaustive list of LUT values (e.g., OpenStep has a lot of weird
+     * ones), but it should cover 99% of the current possibilities. */
+
+#if defined(NeXT)
+    /* third-party utilities can modify the default LUT exponent */
+    LUT_exponent = 1.0 / 2.2;
+    /*
+    if (some_next_function_that_returns_gamma(&next_gamma))
+        LUT_exponent = 1.0 / next_gamma;
+     */
+#elif defined(sgi)
+    LUT_exponent = 1.0 / 1.7;
+    /* there doesn't seem to be any documented function to
+     * get the "gamma" value, so we do it the hard way */
+    infile = fopen("/etc/config/system.glGammaVal", "r");
+    if (infile) {
+        double sgi_gamma;
+
+        fgets(tmpline, 80, infile);
+        fclose(infile);
+        sgi_gamma = atof(tmpline);
+        if (sgi_gamma > 0.0)
+            LUT_exponent = 1.0 / sgi_gamma;
+    }
+#elif defined(Macintosh)
+    LUT_exponent = 1.8 / 2.61;
+    /*
+    if (some_mac_function_that_returns_gamma(&mac_gamma))
+        LUT_exponent = mac_gamma / 2.61;
+     */
+#else
+    LUT_exponent = 1.0;   /* assume no LUT:  most PCs */
+#endif
+
+    /* the defaults above give 1.0, 1.3, 1.5 and 2.2, respectively: */
+    default_display_exponent = LUT_exponent * CRT_exponent;
+
+
+    /* If the user has set the SCREEN_GAMMA environment variable as suggested
+     * (somewhat imprecisely) in the libpng documentation, use that; otherwise
+     * use the default value we just calculated.  Either way, the user may
+     * override this via a command-line option. */
+
+    if ((p = getenv("SCREEN_GAMMA")) != NULL)
+        rpng2_info.display_exponent = atof(p);
+    else
+        rpng2_info.display_exponent = default_display_exponent;
+
+
+    /* Now parse the command line for options and the PNG filename. */
+
+    while (*++argv && !error) {
+        if (!strncmp(*argv, "-display", 2)) {
+            if (!*++argv)
+                ++error;
+            else
+                displayname = *argv;
+        } else if (!strncmp(*argv, "-gamma", 2)) {
+            if (!*++argv)
+                ++error;
+            else {
+                rpng2_info.display_exponent = atof(*argv);
+                if (rpng2_info.display_exponent <= 0.0)
+                    ++error;
+            }
+        } else if (!strncmp(*argv, "-bgcolor", 4)) {
+            if (!*++argv)
+                ++error;
+            else {
+                bgstr = *argv;
+                if (strlen(bgstr) != 7 || bgstr[0] != '#')
+                    ++error;
+                else {
+                    have_bg = TRUE;
+                    bg_image = FALSE;
+                }
+            }
+        } else if (!strncmp(*argv, "-bgpat", 4)) {
+            if (!*++argv)
+                ++error;
+            else {
+                pat = atoi(*argv);
+                if (pat >= 0 && pat < num_bgpat) {
+                    bg_image = TRUE;
+                    have_bg = FALSE;
+                } else
+                    ++error;
+            }
+        } else if (!strncmp(*argv, "-usleep", 2)) {
+            if (!*++argv)
+                ++error;
+            else {
+                usleep_duration = (ulg)atol(*argv);
+                demo_timing = TRUE;
+            }
+        } else if (!strncmp(*argv, "-pause", 2)) {
+            pause_after_pass = TRUE;
+        } else if (!strncmp(*argv, "-timing", 2)) {
+            timing = TRUE;
+#ifdef FEATURE_LOOP
+        } else if (!strncmp(*argv, "-loop", 2)) {
+            loop = TRUE;
+            if (!argv[1] || !is_number(argv[1]))
+                loop_interval = 2;
+            else {
+                ++argv;
+                loop_interval = atol(*argv);
+                if (loop_interval < 0)
+                    loop_interval = 2;
+                else if (loop_interval > 100000)   /* bit more than one day */
+                    loop_interval = 100000;
+            }
+#endif
+        } else {
+            if (**argv != '-') {
+                filename = *argv;
+                if (argv[1])   /* shouldn't be any more args after filename */
+                    ++error;
+            } else
+                ++error;   /* not expecting any other options */
+        }
+    }
+
+    if (!filename)
+        ++error;
+
+
+    /* print usage screen if any errors up to this point */
+
+    if (error) {
+        fprintf(stderr, "\n%s %s:  %s\n\n", PROGNAME, VERSION, appname);
+        readpng2_version_info();
+        fprintf(stderr, "\n"
+          "Usage:  %s [-display xdpy] [-gamma exp] [-bgcolor bg | -bgpat pat]\n"
+#ifdef FEATURE_LOOP
+          "        %*s [-usleep dur | -timing] [-pause] [-loop [sec]] file.png\n\n"
+#else
+          "        %*s [-usleep dur | -timing] [-pause] file.png\n\n"
+#endif
+          "    xdpy\tname of the target X display (e.g., ``hostname:0'')\n"
+          "    exp \ttransfer-function exponent (``gamma'') of the display\n"
+          "\t\t  system in floating-point format (e.g., ``%.1f''); equal\n"
+          "\t\t  to the product of the lookup-table exponent (varies)\n"
+          "\t\t  and the CRT exponent (usually 2.2); must be positive\n"
+          "    bg  \tdesired background color in 7-character hex RGB format\n"
+          "\t\t  (e.g., ``#ff7700'' for orange:  same as HTML colors);\n"
+          "\t\t  used with transparent images; overrides -bgpat\n"
+          "    pat \tdesired background pattern number (0-%d); used with\n"
+          "\t\t  transparent images; overrides -bgcolor\n"
+#ifdef FEATURE_LOOP
+          "    -loop\tloops through background images after initial display\n"
+          "\t\t  is complete (depends on -bgpat)\n"
+          "    sec \tseconds to display each background image (default = 2)\n"
+#endif
+          "    dur \tduration in microseconds to wait after displaying each\n"
+          "\t\t  row (for demo purposes)\n"
+          "    -timing\tenables delay for every block read, to simulate modem\n"
+          "\t\t  download of image (~36 Kbps)\n"
+          "    -pause\tpauses after displaying each pass until mouse clicked\n"
+          "\nPress Q, Esc or mouse button 1 (within image window, after image\n"
+          "is displayed) to quit.\n"
+          "\n", PROGNAME,
+          (int)strlen(PROGNAME), " ", default_display_exponent, num_bgpat-1);
+        exit(1);
+    }
+
+
+    if (!(infile = fopen(filename, "rb"))) {
+        fprintf(stderr, PROGNAME ":  can't open PNG file [%s]\n", filename);
+        ++error;
+    } else {
+        incount = fread(inbuf, 1, INBUFSIZE, infile);
+        if (incount < 8 || !readpng2_check_sig(inbuf, 8)) {
+            fprintf(stderr, PROGNAME
+              ":  [%s] is not a PNG file: incorrect signature\n",
+              filename);
+            ++error;
+        } else if ((rc = readpng2_init(&rpng2_info)) != 0) {
+            switch (rc) {
+                case 2:
+                    fprintf(stderr, PROGNAME
+                      ":  [%s] has bad IHDR (libpng longjmp)\n", filename);
+                    break;
+                case 4:
+                    fprintf(stderr, PROGNAME ":  insufficient memory\n");
+                    break;
+                default:
+                    fprintf(stderr, PROGNAME
+                      ":  unknown readpng2_init() error\n");
+                    break;
+            }
+            ++error;
+        } else {
+            Trace((stderr, "about to call XOpenDisplay()\n"))
+            display = XOpenDisplay(displayname);
+            if (!display) {
+                readpng2_cleanup(&rpng2_info);
+                fprintf(stderr, PROGNAME ":  can't open X display [%s]\n",
+                  displayname? displayname : "default");
+                ++error;
+            }
+        }
+        if (error)
+            fclose(infile);
+    }
+
+
+    if (error) {
+        fprintf(stderr, PROGNAME ":  aborting.\n");
+        exit(2);
+    }
+
+
+    /* set the title-bar string, but make sure buffer doesn't overflow */
+
+    alen = strlen(appname);
+    flen = strlen(filename);
+    if (alen + flen + 3 > 1023)
+        sprintf(titlebar, "%s:  ...%s", appname, filename+(alen+flen+6-1023));
+    else
+        sprintf(titlebar, "%s:  %s", appname, filename);
+
+
+    /* set some final rpng2_info variables before entering main data loop */
+
+    if (have_bg) {
+        unsigned r, g, b;   /* this approach quiets compiler warnings */
+
+        sscanf(bgstr+1, "%2x%2x%2x", &r, &g, &b);
+        rpng2_info.bg_red   = (uch)r;
+        rpng2_info.bg_green = (uch)g;
+        rpng2_info.bg_blue  = (uch)b;
+    } else
+        rpng2_info.need_bgcolor = TRUE;
+
+    rpng2_info.state = kPreInit;
+    rpng2_info.mainprog_init = rpng2_x_init;
+    rpng2_info.mainprog_display_row = rpng2_x_display_row;
+    rpng2_info.mainprog_finish_display = rpng2_x_finish_display;
+
+
+    /* OK, this is the fun part:  call readpng2_decode_data() at the start of
+     * the loop to deal with our first buffer of data (read in above to verify
+     * that the file is a PNG image), then loop through the file and continue
+     * calling the same routine to handle each chunk of data.  It in turn
+     * passes the data to libpng, which will invoke one or more of our call-
+     * backs as decoded data become available.  We optionally call sleep() for
+     * one second per iteration to simulate downloading the image via an analog
+     * modem. */
+
+    for (;;) {
+        Trace((stderr, "about to call readpng2_decode_data()\n"))
+        if (readpng2_decode_data(&rpng2_info, inbuf, incount))
+            ++error;
+        Trace((stderr, "done with readpng2_decode_data()\n"))
+
+        if (error || incount != INBUFSIZE || rpng2_info.state == kDone) {
+            if (rpng2_info.state == kDone) {
+                Trace((stderr, "done decoding PNG image\n"))
+            } else if (ferror(infile)) {
+                fprintf(stderr, PROGNAME
+                  ":  error while reading PNG image file\n");
+                exit(3);
+            } else if (feof(infile)) {
+                fprintf(stderr, PROGNAME ":  end of file reached "
+                  "(unexpectedly) while reading PNG image file\n");
+                exit(3);
+            } else /* if (error) */ {
+                /* will print error message below */
+            }
+            break;
+        }
+
+        if (timing)
+            sleep(1);
+
+        incount = fread(inbuf, 1, INBUFSIZE, infile);
+    }
+
+
+    /* clean up PNG stuff and report any decoding errors */
+
+    fclose(infile);
+    Trace((stderr, "about to call readpng2_cleanup()\n"))
+    readpng2_cleanup(&rpng2_info);
+
+    if (error) {
+        fprintf(stderr, PROGNAME ":  libpng error while decoding PNG image\n");
+        exit(3);
+    }
+
+
+#ifdef FEATURE_LOOP
+
+    if (loop && bg_image) {
+        Trace((stderr, "entering -loop loop (FEATURE_LOOP)\n"))
+        for (;;) {
+            int i, use_sleep;
+            struct timeval now, then;
+
+            /* get current time and add loop_interval to get target time */
+            if (gettimeofday(&then, NULL) == 0) {
+                then.tv_sec += loop_interval;
+                use_sleep = FALSE;
+            } else
+                use_sleep = TRUE;
+
+            /* do quick check for a quit event but don't wait for it */
+            /* GRR BUG:  should also check for Expose events and redraw... */
+            if (XCheckMaskEvent(display, KeyPressMask | ButtonPressMask, &e))
+                if (QUIT(e,k))
+                    break;
+
+            /* generate next background image */
+            if (++pat >= num_bgpat)
+                pat = 0;
+            rpng2_x_reload_bg_image();
+
+            /* wait for timeout, using whatever means are available */
+            if (use_sleep || gettimeofday(&now, NULL) != 0) {
+                for (i = loop_interval;  i > 0;  --i) {
+                    sleep(1);
+                    /* GRR BUG:  also need to check for Expose (and redraw!) */
+                    if (XCheckMaskEvent(display, KeyPressMask | ButtonPressMask,
+                        &e) && QUIT(e,k))
+                        break;
+                }
+            } else {
+                /* Y2038 BUG! */
+                if (now.tv_sec < then.tv_sec ||
+                    (now.tv_sec == then.tv_sec && now.tv_usec < then.tv_usec))
+                {
+                    int quit = FALSE;
+                    long seconds_to_go = then.tv_sec - now.tv_sec;
+                    long usleep_usec;
+
+                    /* basically chew up most of remaining loop-interval with
+                     *  calls to sleep(1) interleaved with checks for quit
+                     *  events, but also recalc time-to-go periodically; when
+                     *  done, clean up any remaining time with usleep() call
+                     *  (could also use SIGALRM, but signals are a pain...) */
+                    while (seconds_to_go-- > 1) {
+                        int seconds_done = 0;
+
+                        for (i = seconds_to_go;  i > 0 && !quit;  --i) {
+                            sleep(1);
+                            /* GRR BUG:  need to check for Expose and redraw */
+                            if (XCheckMaskEvent(display, KeyPressMask |
+                                ButtonPressMask, &e) && QUIT(e,k))
+                                quit = TRUE;
+                            if (++seconds_done > 1000)
+                                break;   /* time to redo seconds_to_go meas. */
+                        }
+                        if (quit)
+                            break;
+
+                        /* OK, more than 1000 seconds since last check:
+                         *  correct the time-to-go measurement for drift */
+                        if (gettimeofday(&now, NULL) == 0) {
+                            if (now.tv_sec >= then.tv_sec)
+                                break;
+                            seconds_to_go = then.tv_sec - now.tv_sec;
+                        } else
+                            ++seconds_to_go;  /* restore what we subtracted */
+                    }
+                    if (quit)
+                        break;   /* breaks outer do-loop, skips redisplay */
+
+                    /* since difference between "now" and "then" is already
+                     *  eaten up to within a couple of seconds, don't need to
+                     *  worry about overflow--but might have overshot (neg.) */
+                    if (gettimeofday(&now, NULL) == 0) {
+                        usleep_usec = 1000000L*(then.tv_sec - now.tv_sec) +
+                          then.tv_usec - now.tv_usec;
+                        if (usleep_usec > 0)
+                            usleep((ulg)usleep_usec);
+                    }
+                }
+            }
+
+            /* composite image against new background and display (note that
+             *  we do not take into account the time spent doing this...) */
+            rpng2_x_redisplay_image (0, 0, rpng2_info.width, rpng2_info.height);
+        }
+
+    } else /* FALL THROUGH and do the normal thing */
+
+#endif /* FEATURE_LOOP */
+
+    /* wait for the user to tell us when to quit */
+
+    if (rpng2_info.state >= kWindowInit) {
+        Trace((stderr, "entering final wait-for-quit-event loop\n"))
+        do {
+            XNextEvent(display, &e);
+            if (e.type == Expose) {
+                XExposeEvent *ex = (XExposeEvent *)&e;
+                rpng2_x_redisplay_image (ex->x, ex->y, ex->width, ex->height);
+            }
+        } while (!QUIT(e,k));
+    } else {
+        fprintf(stderr, PROGNAME ":  init callback never called:  probable "
+          "libpng error while decoding PNG metadata\n");
+        exit(4);
+    }
+
+
+    /* we're done:  clean up all image and X resources and go away */
+
+    Trace((stderr, "about to call rpng2_x_cleanup()\n"))
+    rpng2_x_cleanup();
+
+    return 0;
+}
+
+
+
+
+
+/* this function is called by readpng2_info_callback() in readpng2.c, which
+ * in turn is called by libpng after all of the pre-IDAT chunks have been
+ * read and processed--i.e., we now have enough info to finish initializing */
+
+static void rpng2_x_init(void)
+{
+    ulg i;
+    ulg rowbytes = rpng2_info.rowbytes;
+
+    Trace((stderr, "beginning rpng2_x_init()\n"))
+    Trace((stderr, "  rowbytes = %d\n", rpng2_info.rowbytes))
+    Trace((stderr, "  width  = %ld\n", rpng2_info.width))
+    Trace((stderr, "  height = %ld\n", rpng2_info.height))
+
+    rpng2_info.image_data = (uch *)malloc(rowbytes * rpng2_info.height);
+    if (!rpng2_info.image_data) {
+        readpng2_cleanup(&rpng2_info);
+        return;
+    }
+
+    rpng2_info.row_pointers = (uch **)malloc(rpng2_info.height * sizeof(uch *));
+    if (!rpng2_info.row_pointers) {
+        free(rpng2_info.image_data);
+        rpng2_info.image_data = NULL;
+        readpng2_cleanup(&rpng2_info);
+        return;
+    }
+
+    for (i = 0;  i < rpng2_info.height;  ++i)
+        rpng2_info.row_pointers[i] = rpng2_info.image_data + i*rowbytes;
+
+
+    /* do the basic X initialization stuff, make the window, and fill it with
+     * the user-specified, file-specified or default background color or
+     * pattern */
+
+    if (rpng2_x_create_window()) {
+
+        /* GRR TEMPORARY HACK:  this is fundamentally no different from cases
+         * above; libpng should call our error handler to longjmp() back to us
+         * when png_ptr goes away.  If we/it segfault instead, seems like a
+         * libpng bug... */
+
+        /* we're here via libpng callback, so if window fails, clean and bail */
+        readpng2_cleanup(&rpng2_info);
+        rpng2_x_cleanup();
+        exit(2);
+    }
+
+    rpng2_info.state = kWindowInit;
+}
+
+
+
+
+
+static int rpng2_x_create_window(void)
+{
+    ulg bg_red   = rpng2_info.bg_red;
+    ulg bg_green = rpng2_info.bg_green;
+    ulg bg_blue  = rpng2_info.bg_blue;
+    ulg bg_pixel = 0L;
+    ulg attrmask;
+    int need_colormap = FALSE;
+    int screen, pad;
+    uch *xdata;
+    Window root;
+    XEvent e;
+    XGCValues gcvalues;
+    XSetWindowAttributes attr;
+    XTextProperty windowName, *pWindowName = &windowName;
+    XTextProperty iconName, *pIconName = &iconName;
+    XVisualInfo visual_info;
+    XSizeHints *size_hints;
+    XWMHints *wm_hints;
+    XClassHint *class_hints;
+
+
+    Trace((stderr, "beginning rpng2_x_create_window()\n"))
+
+    screen = DefaultScreen(display);
+    depth = DisplayPlanes(display, screen);
+    root = RootWindow(display, screen);
+
+#ifdef DEBUG
+    XSynchronize(display, True);
+#endif
+
+    if (depth != 16 && depth != 24 && depth != 32) {
+        int visuals_matched = 0;
+
+        Trace((stderr, "default depth is %d:  checking other visuals\n",
+          depth))
+
+        /* 24-bit first */
+        visual_info.screen = screen;
+        visual_info.depth = 24;
+        visual_list = XGetVisualInfo(display,
+          VisualScreenMask | VisualDepthMask, &visual_info, &visuals_matched);
+        if (visuals_matched == 0) {
+/* GRR:  add 15-, 16- and 32-bit TrueColor visuals (also DirectColor?) */
+            fprintf(stderr, "default screen depth %d not supported, and no"
+              " 24-bit visuals found\n", depth);
+            return 2;
+        }
+        Trace((stderr, "XGetVisualInfo() returned %d 24-bit visuals\n",
+          visuals_matched))
+        visual = visual_list[0].visual;
+        depth = visual_list[0].depth;
+/*
+        colormap_size = visual_list[0].colormap_size;
+        visual_class = visual->class;
+        visualID = XVisualIDFromVisual(visual);
+ */
+        have_nondefault_visual = TRUE;
+        need_colormap = TRUE;
+    } else {
+        XMatchVisualInfo(display, screen, depth, TrueColor, &visual_info);
+        visual = visual_info.visual;
+    }
+
+    RMask = visual->red_mask;
+    GMask = visual->green_mask;
+    BMask = visual->blue_mask;
+
+/* GRR:  add/check 8-bit support */
+    if (depth == 8 || need_colormap) {
+        colormap = XCreateColormap(display, root, visual, AllocNone);
+        if (!colormap) {
+            fprintf(stderr, "XCreateColormap() failed\n");
+            return 2;
+        }
+        have_colormap = TRUE;
+        if (depth == 8)
+            bg_image = FALSE;   /* gradient just wastes palette entries */
+    }
+    if (depth == 15 || depth == 16) {
+        RShift = 15 - rpng2_x_msb(RMask);    /* these are right-shifts */
+        GShift = 15 - rpng2_x_msb(GMask);
+        BShift = 15 - rpng2_x_msb(BMask);
+    } else if (depth > 16) {
+        RShift = rpng2_x_msb(RMask) - 7;     /* these are left-shifts */
+        GShift = rpng2_x_msb(GMask) - 7;
+        BShift = rpng2_x_msb(BMask) - 7;
+    }
+    if (depth >= 15 && (RShift < 0 || GShift < 0 || BShift < 0)) {
+        fprintf(stderr, "rpng2 internal logic error:  negative X shift(s)!\n");
+        return 2;
+    }
+
+/*---------------------------------------------------------------------------
+    Finally, create the window.
+  ---------------------------------------------------------------------------*/
+
+    attr.backing_store = Always;
+    attr.event_mask = ExposureMask | KeyPressMask | ButtonPressMask;
+    attrmask = CWBackingStore | CWEventMask;
+    if (have_nondefault_visual) {
+        attr.colormap = colormap;
+        attr.background_pixel = 0;
+        attr.border_pixel = 1;
+        attrmask |= CWColormap | CWBackPixel | CWBorderPixel;
+    }
+
+    window = XCreateWindow(display, root, 0, 0, rpng2_info.width,
+      rpng2_info.height, 0, depth, InputOutput, visual, attrmask, &attr);
+
+    if (window == None) {
+        fprintf(stderr, "XCreateWindow() failed\n");
+        return 2;
+    } else
+        have_window = TRUE;
+
+    if (depth == 8)
+        XSetWindowColormap(display, window, colormap);
+
+    if (!XStringListToTextProperty(&window_name, 1, pWindowName))
+        pWindowName = NULL;
+    if (!XStringListToTextProperty(&icon_name, 1, pIconName))
+        pIconName = NULL;
+
+    /* OK if either hints allocation fails; XSetWMProperties() allows NULLs */
+
+    if ((size_hints = XAllocSizeHints()) != NULL) {
+        /* window will not be resizable */
+        size_hints->flags = PMinSize | PMaxSize;
+        size_hints->min_width = size_hints->max_width = (int)rpng2_info.width;
+        size_hints->min_height = size_hints->max_height =
+          (int)rpng2_info.height;
+    }
+
+    if ((wm_hints = XAllocWMHints()) != NULL) {
+        wm_hints->initial_state = NormalState;
+        wm_hints->input = True;
+     /* wm_hints->icon_pixmap = icon_pixmap; */
+        wm_hints->flags = StateHint | InputHint  /* | IconPixmapHint */ ;
+    }
+
+    if ((class_hints = XAllocClassHint()) != NULL) {
+        class_hints->res_name = res_name;
+        class_hints->res_class = res_class;
+    }
+
+    XSetWMProperties(display, window, pWindowName, pIconName, NULL, 0,
+      size_hints, wm_hints, class_hints);
+
+    /* various properties and hints no longer needed; free memory */
+    if (pWindowName)
+       XFree(pWindowName->value);
+    if (pIconName)
+       XFree(pIconName->value);
+    if (size_hints)
+        XFree(size_hints);
+    if (wm_hints)
+       XFree(wm_hints);
+    if (class_hints)
+       XFree(class_hints);
+
+    XMapWindow(display, window);
+
+    gc = XCreateGC(display, window, 0, &gcvalues);
+    have_gc = TRUE;
+
+/*---------------------------------------------------------------------------
+    Allocate memory for the X- and display-specific version of the image.
+  ---------------------------------------------------------------------------*/
+
+    if (depth == 24 || depth == 32) {
+        xdata = (uch *)malloc(4*rpng2_info.width*rpng2_info.height);
+        pad = 32;
+    } else if (depth == 16) {
+        xdata = (uch *)malloc(2*rpng2_info.width*rpng2_info.height);
+        pad = 16;
+    } else /* depth == 8 */ {
+        xdata = (uch *)malloc(rpng2_info.width*rpng2_info.height);
+        pad = 8;
+    }
+
+    if (!xdata) {
+        fprintf(stderr, PROGNAME ":  unable to allocate image memory\n");
+        return 4;
+    }
+
+    ximage = XCreateImage(display, visual, depth, ZPixmap, 0,
+      (char *)xdata, rpng2_info.width, rpng2_info.height, pad, 0);
+
+    if (!ximage) {
+        fprintf(stderr, PROGNAME ":  XCreateImage() failed\n");
+        free(xdata);
+        return 3;
+    }
+
+    /* to avoid testing the byte order every pixel (or doubling the size of
+     * the drawing routine with a giant if-test), we arbitrarily set the byte
+     * order to MSBFirst and let Xlib worry about inverting things on little-
+     * endian machines (e.g., Linux/x86, old VAXen, etc.)--this is not the
+     * most efficient approach (the giant if-test would be better), but in
+     * the interest of clarity, we'll take the easy way out... */
+
+    ximage->byte_order = MSBFirst;
+
+/*---------------------------------------------------------------------------
+    Fill window with the specified background color (default is black) or
+    faked "background image" (but latter is disabled if 8-bit; gradients
+    just waste palette entries).
+  ---------------------------------------------------------------------------*/
+
+    if (bg_image)
+        rpng2_x_load_bg_image();    /* resets bg_image if fails */
+
+    if (!bg_image) {
+        if (depth == 24 || depth == 32) {
+            bg_pixel = (bg_red   << RShift) |
+                       (bg_green << GShift) |
+                       (bg_blue  << BShift);
+        } else if (depth == 16) {
+            bg_pixel = (((bg_red   << 8) >> RShift) & RMask) |
+                       (((bg_green << 8) >> GShift) & GMask) |
+                       (((bg_blue  << 8) >> BShift) & BMask);
+        } else /* depth == 8 */ {
+
+            /* GRR:  add 8-bit support */
+
+        }
+        XSetForeground(display, gc, bg_pixel);
+        XFillRectangle(display, window, gc, 0, 0, rpng2_info.width,
+          rpng2_info.height);
+    }
+
+/*---------------------------------------------------------------------------
+    Wait for first Expose event to do any drawing, then flush and return.
+  ---------------------------------------------------------------------------*/
+
+    do
+        XNextEvent(display, &e);
+    while (e.type != Expose || e.xexpose.count);
+
+    XFlush(display);
+
+    return 0;
+
+} /* end function rpng2_x_create_window() */
+
+
+
+
+
+static int rpng2_x_load_bg_image(void)
+{
+    uch *src;
+    char *dest;
+    uch r1, r2, g1, g2, b1, b2;
+    uch r1_inv, r2_inv, g1_inv, g2_inv, b1_inv, b2_inv;
+    int k, hmax, max;
+    int xidx, yidx, yidx_max;
+    int even_odd_vert, even_odd_horiz, even_odd;
+    int invert_gradient2 = (bg[pat].type & 0x08);
+    int invert_column;
+    int ximage_rowbytes = ximage->bytes_per_line;
+    ulg i, row;
+    ulg pixel;
+
+/*---------------------------------------------------------------------------
+    Allocate buffer for fake background image to be used with transparent
+    images; if this fails, revert to plain background color.
+  ---------------------------------------------------------------------------*/
+
+    bg_rowbytes = 3 * rpng2_info.width;
+    bg_data = (uch *)malloc(bg_rowbytes * rpng2_info.height);
+    if (!bg_data) {
+        fprintf(stderr, PROGNAME
+          ":  unable to allocate memory for background image\n");
+        bg_image = 0;
+        return 1;
+    }
+
+    bgscale = (pat == 0)? 8 : bgscale_default;
+    yidx_max = bgscale - 1;
+
+/*---------------------------------------------------------------------------
+    Vertical gradients (ramps) in NxN squares, alternating direction and
+    colors (N == bgscale).
+  ---------------------------------------------------------------------------*/
+
+    if ((bg[pat].type & 0x07) == 0) {
+        uch r1_min  = rgb[bg[pat].rgb1_min].r;
+        uch g1_min  = rgb[bg[pat].rgb1_min].g;
+        uch b1_min  = rgb[bg[pat].rgb1_min].b;
+        uch r2_min  = rgb[bg[pat].rgb2_min].r;
+        uch g2_min  = rgb[bg[pat].rgb2_min].g;
+        uch b2_min  = rgb[bg[pat].rgb2_min].b;
+        int r1_diff = rgb[bg[pat].rgb1_max].r - r1_min;
+        int g1_diff = rgb[bg[pat].rgb1_max].g - g1_min;
+        int b1_diff = rgb[bg[pat].rgb1_max].b - b1_min;
+        int r2_diff = rgb[bg[pat].rgb2_max].r - r2_min;
+        int g2_diff = rgb[bg[pat].rgb2_max].g - g2_min;
+        int b2_diff = rgb[bg[pat].rgb2_max].b - b2_min;
+
+        for (row = 0;  row < rpng2_info.height;  ++row) {
+            yidx = (int)(row % bgscale);
+            even_odd_vert = (int)((row / bgscale) & 1);
+
+            r1 = r1_min + (r1_diff * yidx) / yidx_max;
+            g1 = g1_min + (g1_diff * yidx) / yidx_max;
+            b1 = b1_min + (b1_diff * yidx) / yidx_max;
+            r1_inv = r1_min + (r1_diff * (yidx_max-yidx)) / yidx_max;
+            g1_inv = g1_min + (g1_diff * (yidx_max-yidx)) / yidx_max;
+            b1_inv = b1_min + (b1_diff * (yidx_max-yidx)) / yidx_max;
+
+            r2 = r2_min + (r2_diff * yidx) / yidx_max;
+            g2 = g2_min + (g2_diff * yidx) / yidx_max;
+            b2 = b2_min + (b2_diff * yidx) / yidx_max;
+            r2_inv = r2_min + (r2_diff * (yidx_max-yidx)) / yidx_max;
+            g2_inv = g2_min + (g2_diff * (yidx_max-yidx)) / yidx_max;
+            b2_inv = b2_min + (b2_diff * (yidx_max-yidx)) / yidx_max;
+
+            dest = (char *)bg_data + row*bg_rowbytes;
+            for (i = 0;  i < rpng2_info.width;  ++i) {
+                even_odd_horiz = (int)((i / bgscale) & 1);
+                even_odd = even_odd_vert ^ even_odd_horiz;
+                invert_column =
+                  (even_odd_horiz && (bg[pat].type & 0x10));
+                if (even_odd == 0) {        /* gradient #1 */
+                    if (invert_column) {
+                        *dest++ = r1_inv;
+                        *dest++ = g1_inv;
+                        *dest++ = b1_inv;
+                    } else {
+                        *dest++ = r1;
+                        *dest++ = g1;
+                        *dest++ = b1;
+                    }
+                } else {                    /* gradient #2 */
+                    if ((invert_column && invert_gradient2) ||
+                        (!invert_column && !invert_gradient2))
+                    {
+                        *dest++ = r2;       /* not inverted or */
+                        *dest++ = g2;       /*  doubly inverted */
+                        *dest++ = b2;
+                    } else {
+                        *dest++ = r2_inv;
+                        *dest++ = g2_inv;   /* singly inverted */
+                        *dest++ = b2_inv;
+                    }
+                }
+            }
+        }
+
+/*---------------------------------------------------------------------------
+    Soft gradient-diamonds with scale = bgscale.  Code contributed by Adam
+    M. Costello.
+  ---------------------------------------------------------------------------*/
+
+    } else if ((bg[pat].type & 0x07) == 1) {
+
+        hmax = (bgscale-1)/2;   /* half the max weight of a color */
+        max = 2*hmax;           /* the max weight of a color */
+
+        r1 = rgb[bg[pat].rgb1_max].r;
+        g1 = rgb[bg[pat].rgb1_max].g;
+        b1 = rgb[bg[pat].rgb1_max].b;
+        r2 = rgb[bg[pat].rgb2_max].r;
+        g2 = rgb[bg[pat].rgb2_max].g;
+        b2 = rgb[bg[pat].rgb2_max].b;
+
+        for (row = 0;  row < rpng2_info.height;  ++row) {
+            yidx = (int)(row % bgscale);
+            if (yidx > hmax)
+                yidx = bgscale-1 - yidx;
+            dest = (char *)bg_data + row*bg_rowbytes;
+            for (i = 0;  i < rpng2_info.width;  ++i) {
+                xidx = (int)(i % bgscale);
+                if (xidx > hmax)
+                    xidx = bgscale-1 - xidx;
+                k = xidx + yidx;
+                *dest++ = (k*r1 + (max-k)*r2) / max;
+                *dest++ = (k*g1 + (max-k)*g2) / max;
+                *dest++ = (k*b1 + (max-k)*b2) / max;
+            }
+        }
+
+/*---------------------------------------------------------------------------
+    Radial "starburst" with azimuthal sinusoids; [eventually number of sinu-
+    soids will equal bgscale?].  This one is slow but very cool.  Code con-
+    tributed by Pieter S. van der Meulen (originally in Smalltalk).
+  ---------------------------------------------------------------------------*/
+
+    } else if ((bg[pat].type & 0x07) == 2) {
+        uch ch;
+        int ii, x, y, hw, hh, grayspot;
+        double freq, rotate, saturate, gray, intensity;
+        double angle=0.0, aoffset=0.0, maxDist, dist;
+        double red=0.0, green=0.0, blue=0.0, hue, s, v, f, p, q, t;
+
+        fprintf(stderr, "%s:  computing radial background...",
+          PROGNAME);
+        fflush(stderr);
+
+        hh = (int)(rpng2_info.height / 2);
+        hw = (int)(rpng2_info.width / 2);
+
+        /* variables for radial waves:
+         *   aoffset:  number of degrees to rotate hue [CURRENTLY NOT USED]
+         *   freq:  number of color beams originating from the center
+         *   grayspot:  size of the graying center area (anti-alias)
+         *   rotate:  rotation of the beams as a function of radius
+         *   saturate:  saturation of beams' shape azimuthally
+         */
+        angle = CLIP(angle, 0.0, 360.0);
+        grayspot = CLIP(bg[pat].bg_gray, 1, (hh + hw));
+        freq = MAX((double)bg[pat].bg_freq, 0.0);
+        saturate = (double)bg[pat].bg_bsat * 0.1;
+        rotate = (double)bg[pat].bg_brot * 0.1;
+        gray = 0.0;
+        intensity = 0.0;
+        maxDist = (double)((hw*hw) + (hh*hh));
+
+        for (row = 0;  row < rpng2_info.height;  ++row) {
+            y = (int)(row - hh);
+            dest = (char *)bg_data + row*bg_rowbytes;
+            for (i = 0;  i < rpng2_info.width;  ++i) {
+                x = (int)(i - hw);
+                angle = (x == 0)? PI_2 : atan((double)y / (double)x);
+                gray = (double)MAX(ABS(y), ABS(x)) / grayspot;
+                gray = MIN(1.0, gray);
+                dist = (double)((x*x) + (y*y)) / maxDist;
+                intensity = cos((angle+(rotate*dist*PI)) * freq) *
+                  gray * saturate;
+                intensity = (MAX(MIN(intensity,1.0),-1.0) + 1.0) * 0.5;
+                hue = (angle + PI) * INV_PI_360 + aoffset;
+                s = gray * ((double)(ABS(x)+ABS(y)) / (double)(hw + hh));
+                s = MIN(MAX(s,0.0), 1.0);
+                v = MIN(MAX(intensity,0.0), 1.0);
+
+                if (s == 0.0) {
+                    ch = (uch)(v * 255.0);
+                    *dest++ = ch;
+                    *dest++ = ch;
+                    *dest++ = ch;
+                } else {
+                    if ((hue < 0.0) || (hue >= 360.0))
+                        hue -= (((int)(hue / 360.0)) * 360.0);
+                    hue /= 60.0;
+                    ii = (int)hue;
+                    f = hue - (double)ii;
+                    p = (1.0 - s) * v;
+                    q = (1.0 - (s * f)) * v;
+                    t = (1.0 - (s * (1.0 - f))) * v;
+                    if      (ii == 0) { red = v; green = t; blue = p; }
+                    else if (ii == 1) { red = q; green = v; blue = p; }
+                    else if (ii == 2) { red = p; green = v; blue = t; }
+                    else if (ii == 3) { red = p; green = q; blue = v; }
+                    else if (ii == 4) { red = t; green = p; blue = v; }
+                    else if (ii == 5) { red = v; green = p; blue = q; }
+                    *dest++ = (uch)(red * 255.0);
+                    *dest++ = (uch)(green * 255.0);
+                    *dest++ = (uch)(blue * 255.0);
+                }
+            }
+        }
+        fprintf(stderr, "done.\n");
+        fflush(stderr);
+    }
+
+/*---------------------------------------------------------------------------
+    Blast background image to display buffer before beginning PNG decode.
+  ---------------------------------------------------------------------------*/
+
+    if (depth == 24 || depth == 32) {
+        ulg red, green, blue;
+        int bpp = ximage->bits_per_pixel;
+
+        for (row = 0;  row < rpng2_info.height;  ++row) {
+            src = bg_data + row*bg_rowbytes;
+            dest = ximage->data + row*ximage_rowbytes;
+            if (bpp == 32) {    /* slightly optimized version */
+                for (i = rpng2_info.width;  i > 0;  --i) {
+                    red   = *src++;
+                    green = *src++;
+                    blue  = *src++;
+                    pixel = (red   << RShift) |
+                            (green << GShift) |
+                            (blue  << BShift);
+                    /* recall that we set ximage->byte_order = MSBFirst above */
+                    *dest++ = (char)((pixel >> 24) & 0xff);
+                    *dest++ = (char)((pixel >> 16) & 0xff);
+                    *dest++ = (char)((pixel >>  8) & 0xff);
+                    *dest++ = (char)( pixel        & 0xff);
+                }
+            } else {
+                for (i = rpng2_info.width;  i > 0;  --i) {
+                    red   = *src++;
+                    green = *src++;
+                    blue  = *src++;
+                    pixel = (red   << RShift) |
+                            (green << GShift) |
+                            (blue  << BShift);
+                    /* recall that we set ximage->byte_order = MSBFirst above */
+                    /* GRR BUG?  this assumes bpp == 24 & bits are packed low */
+                    /*           (probably need to use RShift, RMask, etc.) */
+                    *dest++ = (char)((pixel >> 16) & 0xff);
+                    *dest++ = (char)((pixel >>  8) & 0xff);
+                    *dest++ = (char)( pixel        & 0xff);
+                }
+            }
+        }
+
+    } else if (depth == 16) {
+        ush red, green, blue;
+
+        for (row = 0;  row < rpng2_info.height;  ++row) {
+            src = bg_data + row*bg_rowbytes;
+            dest = ximage->data + row*ximage_rowbytes;
+            for (i = rpng2_info.width;  i > 0;  --i) {
+                red   = ((ush)(*src) << 8);  ++src;
+                green = ((ush)(*src) << 8);  ++src;
+                blue  = ((ush)(*src) << 8);  ++src;
+                pixel = ((red   >> RShift) & RMask) |
+                        ((green >> GShift) & GMask) |
+                        ((blue  >> BShift) & BMask);
+                /* recall that we set ximage->byte_order = MSBFirst above */
+                *dest++ = (char)((pixel >>  8) & 0xff);
+                *dest++ = (char)( pixel        & 0xff);
+            }
+        }
+
+    } else /* depth == 8 */ {
+
+        /* GRR:  add 8-bit support */
+
+    }
+
+    XPutImage(display, window, gc, ximage, 0, 0, 0, 0, rpng2_info.width,
+      rpng2_info.height);
+
+    return 0;
+
+} /* end function rpng2_x_load_bg_image() */
+
+
+
+
+
+static void rpng2_x_display_row(ulg row)
+{
+    uch bg_red   = rpng2_info.bg_red;
+    uch bg_green = rpng2_info.bg_green;
+    uch bg_blue  = rpng2_info.bg_blue;
+    uch *src, *src2=NULL;
+    char *dest;
+    uch r, g, b, a;
+    int ximage_rowbytes = ximage->bytes_per_line;
+    ulg i, pixel;
+    static int rows=0, prevpass=(-1);
+    static ulg firstrow;
+
+/*---------------------------------------------------------------------------
+    rows and firstrow simply track how many rows (and which ones) have not
+    yet been displayed; alternatively, we could call XPutImage() for every
+    row and not bother with the records-keeping.
+  ---------------------------------------------------------------------------*/
+
+    Trace((stderr, "beginning rpng2_x_display_row()\n"))
+
+    if (rpng2_info.pass != prevpass) {
+        if (pause_after_pass && rpng2_info.pass > 0) {
+            XEvent e;
+            KeySym k;
+
+            fprintf(stderr,
+              "%s:  end of pass %d of 7; click in image window to continue\n",
+              PROGNAME, prevpass + 1);
+            do
+                XNextEvent(display, &e);
+            while (!QUIT(e,k));
+        }
+        fprintf(stderr, "%s:  pass %d of 7\r", PROGNAME, rpng2_info.pass + 1);
+        fflush(stderr);
+        prevpass = rpng2_info.pass;
+    }
+
+    if (rows == 0)
+        firstrow = row;   /* first row that is not yet displayed */
+
+    ++rows;   /* count of rows received but not yet displayed */
+
+/*---------------------------------------------------------------------------
+    Aside from the use of the rpng2_info struct, the lack of an outer loop
+    (over rows) and moving the XPutImage() call outside the "if (depth)"
+    tests, this routine is identical to rpng_x_display_image() in the non-
+    progressive version of the program.
+  ---------------------------------------------------------------------------*/
+
+    if (depth == 24 || depth == 32) {
+        ulg red, green, blue;
+        int bpp = ximage->bits_per_pixel;
+
+        src = rpng2_info.image_data + row*rpng2_info.rowbytes;
+        if (bg_image)
+            src2 = bg_data + row*bg_rowbytes;
+        dest = ximage->data + row*ximage_rowbytes;
+        if (rpng2_info.channels == 3) {
+            for (i = rpng2_info.width;  i > 0;  --i) {
+                red   = *src++;
+                green = *src++;
+                blue  = *src++;
+                pixel = (red   << RShift) |
+                        (green << GShift) |
+                        (blue  << BShift);
+                /* recall that we set ximage->byte_order = MSBFirst above */
+                if (bpp == 32) {
+                    *dest++ = (char)((pixel >> 24) & 0xff);
+                    *dest++ = (char)((pixel >> 16) & 0xff);
+                    *dest++ = (char)((pixel >>  8) & 0xff);
+                    *dest++ = (char)( pixel        & 0xff);
+                } else {
+                    /* GRR BUG?  this assumes bpp == 24 & bits are packed low */
+                    /*           (probably need to use RShift, RMask, etc.) */
+                    *dest++ = (char)((pixel >> 16) & 0xff);
+                    *dest++ = (char)((pixel >>  8) & 0xff);
+                    *dest++ = (char)( pixel        & 0xff);
+                }
+            }
+        } else /* if (rpng2_info.channels == 4) */ {
+            for (i = rpng2_info.width;  i > 0;  --i) {
+                r = *src++;
+                g = *src++;
+                b = *src++;
+                a = *src++;
+                if (bg_image) {
+                    bg_red   = *src2++;
+                    bg_green = *src2++;
+                    bg_blue  = *src2++;
+                }
+                if (a == 255) {
+                    red   = r;
+                    green = g;
+                    blue  = b;
+                } else if (a == 0) {
+                    red   = bg_red;
+                    green = bg_green;
+                    blue  = bg_blue;
+                } else {
+                    /* this macro (from png.h) composites the foreground
+                     * and background values and puts the result into the
+                     * first argument */
+                    alpha_composite(red,   r, a, bg_red);
+                    alpha_composite(green, g, a, bg_green);
+                    alpha_composite(blue,  b, a, bg_blue);
+                }
+                pixel = (red   << RShift) |
+                        (green << GShift) |
+                        (blue  << BShift);
+                /* recall that we set ximage->byte_order = MSBFirst above */
+                if (bpp == 32) {
+                    *dest++ = (char)((pixel >> 24) & 0xff);
+                    *dest++ = (char)((pixel >> 16) & 0xff);
+                    *dest++ = (char)((pixel >>  8) & 0xff);
+                    *dest++ = (char)( pixel        & 0xff);
+                } else {
+                    /* GRR BUG?  this assumes bpp == 24 & bits are packed low */
+                    /*           (probably need to use RShift, RMask, etc.) */
+                    *dest++ = (char)((pixel >> 16) & 0xff);
+                    *dest++ = (char)((pixel >>  8) & 0xff);
+                    *dest++ = (char)( pixel        & 0xff);
+                }
+            }
+        }
+
+    } else if (depth == 16) {
+        ush red, green, blue;
+
+        src = rpng2_info.row_pointers[row];
+        if (bg_image)
+            src2 = bg_data + row*bg_rowbytes;
+        dest = ximage->data + row*ximage_rowbytes;
+        if (rpng2_info.channels == 3) {
+            for (i = rpng2_info.width;  i > 0;  --i) {
+                red   = ((ush)(*src) << 8);
+                ++src;
+                green = ((ush)(*src) << 8);
+                ++src;
+                blue  = ((ush)(*src) << 8);
+                ++src;
+                pixel = ((red   >> RShift) & RMask) |
+                        ((green >> GShift) & GMask) |
+                        ((blue  >> BShift) & BMask);
+                /* recall that we set ximage->byte_order = MSBFirst above */
+                *dest++ = (char)((pixel >>  8) & 0xff);
+                *dest++ = (char)( pixel        & 0xff);
+            }
+        } else /* if (rpng2_info.channels == 4) */ {
+            for (i = rpng2_info.width;  i > 0;  --i) {
+                r = *src++;
+                g = *src++;
+                b = *src++;
+                a = *src++;
+                if (bg_image) {
+                    bg_red   = *src2++;
+                    bg_green = *src2++;
+                    bg_blue  = *src2++;
+                }
+                if (a == 255) {
+                    red   = ((ush)r << 8);
+                    green = ((ush)g << 8);
+                    blue  = ((ush)b << 8);
+                } else if (a == 0) {
+                    red   = ((ush)bg_red   << 8);
+                    green = ((ush)bg_green << 8);
+                    blue  = ((ush)bg_blue  << 8);
+                } else {
+                    /* this macro (from png.h) composites the foreground
+                     * and background values and puts the result back into
+                     * the first argument (== fg byte here:  safe) */
+                    alpha_composite(r, r, a, bg_red);
+                    alpha_composite(g, g, a, bg_green);
+                    alpha_composite(b, b, a, bg_blue);
+                    red   = ((ush)r << 8);
+                    green = ((ush)g << 8);
+                    blue  = ((ush)b << 8);
+                }
+                pixel = ((red   >> RShift) & RMask) |
+                        ((green >> GShift) & GMask) |
+                        ((blue  >> BShift) & BMask);
+                /* recall that we set ximage->byte_order = MSBFirst above */
+                *dest++ = (char)((pixel >>  8) & 0xff);
+                *dest++ = (char)( pixel        & 0xff);
+            }
+        }
+
+    } else /* depth == 8 */ {
+
+        /* GRR:  add 8-bit support */
+
+    }
+
+
+/*---------------------------------------------------------------------------
+    Display after every 16 rows or when on one of last two rows.  (Region
+    may include previously displayed lines due to interlacing--i.e., not
+    contiguous.  Also, second-to-last row is final one in interlaced images
+    with odd number of rows.)  For demos, flush (and delay) after every 16th
+    row so "sparse" passes don't go twice as fast.
+  ---------------------------------------------------------------------------*/
+
+    if (demo_timing && (row - firstrow >= 16 || row >= rpng2_info.height-2)) {
+        XPutImage(display, window, gc, ximage, 0, (int)firstrow, 0,
+          (int)firstrow, rpng2_info.width, row - firstrow + 1);
+        XFlush(display);
+        rows = 0;
+        usleep(usleep_duration);
+    } else
+    if (!demo_timing && ((rows & 0xf) == 0 || row >= rpng2_info.height-2)) {
+        XPutImage(display, window, gc, ximage, 0, (int)firstrow, 0,
+          (int)firstrow, rpng2_info.width, row - firstrow + 1);
+        XFlush(display);
+        rows = 0;
+    }
+
+}
+
+
+
+
+
+static void rpng2_x_finish_display(void)
+{
+    Trace((stderr, "beginning rpng2_x_finish_display()\n"))
+
+    /* last row has already been displayed by rpng2_x_display_row(), so we
+     * have nothing to do here except set a flag and let the user know that
+     * the image is done */
+
+    rpng2_info.state = kDone;
+    printf(
+      "Done.  Press Q, Esc or mouse button 1 (within image window) to quit.\n");
+    fflush(stdout);
+}
+
+
+
+
+
+static void rpng2_x_redisplay_image(ulg startcol, ulg startrow,
+                                    ulg width, ulg height)
+{
+    uch bg_red   = rpng2_info.bg_red;
+    uch bg_green = rpng2_info.bg_green;
+    uch bg_blue  = rpng2_info.bg_blue;
+    uch *src, *src2=NULL;
+    char *dest;
+    uch r, g, b, a;
+    ulg i, row, lastrow = 0;
+    ulg pixel;
+    int ximage_rowbytes = ximage->bytes_per_line;
+
+
+    Trace((stderr, "beginning display loop (image_channels == %d)\n",
+      rpng2_info.channels))
+    Trace((stderr, "   (width = %ld, rowbytes = %d, ximage_rowbytes = %d)\n",
+      rpng2_info.width, rpng2_info.rowbytes, ximage_rowbytes))
+    Trace((stderr, "   (bpp = %d)\n", ximage->bits_per_pixel))
+    Trace((stderr, "   (byte_order = %s)\n", ximage->byte_order == MSBFirst?
+      "MSBFirst" : (ximage->byte_order == LSBFirst? "LSBFirst" : "unknown")))
+
+/*---------------------------------------------------------------------------
+    Aside from the use of the rpng2_info struct and of src2 (for background
+    image), this routine is identical to rpng_x_display_image() in the non-
+    progressive version of the program--for the simple reason that redisplay
+    of the image against a new background happens after the image is fully
+    decoded and therefore is, by definition, non-progressive.
+  ---------------------------------------------------------------------------*/
+
+    if (depth == 24 || depth == 32) {
+        ulg red, green, blue;
+        int bpp = ximage->bits_per_pixel;
+
+        for (lastrow = row = startrow;  row < startrow+height;  ++row) {
+            src = rpng2_info.image_data + row*rpng2_info.rowbytes;
+            if (bg_image)
+                src2 = bg_data + row*bg_rowbytes;
+            dest = ximage->data + row*ximage_rowbytes;
+            if (rpng2_info.channels == 3) {
+                for (i = rpng2_info.width;  i > 0;  --i) {
+                    red   = *src++;
+                    green = *src++;
+                    blue  = *src++;
+#ifdef NO_24BIT_MASKS
+                    pixel = (red   << RShift) |
+                            (green << GShift) |
+                            (blue  << BShift);
+                    /* recall that we set ximage->byte_order = MSBFirst above */
+                    if (bpp == 32) {
+                        *dest++ = (char)((pixel >> 24) & 0xff);
+                        *dest++ = (char)((pixel >> 16) & 0xff);
+                        *dest++ = (char)((pixel >>  8) & 0xff);
+                        *dest++ = (char)( pixel        & 0xff);
+                    } else {
+                        /* this assumes bpp == 24 & bits are packed low */
+                        /* (probably need to use RShift, RMask, etc.) */
+                        *dest++ = (char)((pixel >> 16) & 0xff);
+                        *dest++ = (char)((pixel >>  8) & 0xff);
+                        *dest++ = (char)( pixel        & 0xff);
+                    }
+#else
+                    red   = (RShift < 0)? red   << (-RShift) : red   >> RShift;
+                    green = (GShift < 0)? green << (-GShift) : green >> GShift;
+                    blue  = (BShift < 0)? blue  << (-BShift) : blue  >> BShift;
+                    pixel = (red & RMask) | (green & GMask) | (blue & BMask);
+                    /* recall that we set ximage->byte_order = MSBFirst above */
+                    if (bpp == 32) {
+                        *dest++ = (char)((pixel >> 24) & 0xff);
+                        *dest++ = (char)((pixel >> 16) & 0xff);
+                        *dest++ = (char)((pixel >>  8) & 0xff);
+                        *dest++ = (char)( pixel        & 0xff);
+                    } else {
+                        /* GRR BUG */
+                        /* this assumes bpp == 24 & bits are packed low */
+                        /* (probably need to use RShift/RMask/etc. here, too) */
+                        *dest++ = (char)((pixel >> 16) & 0xff);
+                        *dest++ = (char)((pixel >>  8) & 0xff);
+                        *dest++ = (char)( pixel        & 0xff);
+                    }
+#endif
+                }
+
+            } else /* if (rpng2_info.channels == 4) */ {
+                for (i = rpng2_info.width;  i > 0;  --i) {
+                    r = *src++;
+                    g = *src++;
+                    b = *src++;
+                    a = *src++;
+                    if (bg_image) {
+                        bg_red   = *src2++;
+                        bg_green = *src2++;
+                        bg_blue  = *src2++;
+                    }
+                    if (a == 255) {
+                        red   = r;
+                        green = g;
+                        blue  = b;
+                    } else if (a == 0) {
+                        red   = bg_red;
+                        green = bg_green;
+                        blue  = bg_blue;
+                    } else {
+                        /* this macro (from png.h) composites the foreground
+                         * and background values and puts the result into the
+                         * first argument */
+                        alpha_composite(red,   r, a, bg_red);
+                        alpha_composite(green, g, a, bg_green);
+                        alpha_composite(blue,  b, a, bg_blue);
+                    }
+#ifdef NO_24BIT_MASKS
+                    pixel = (red   << RShift) |
+                            (green << GShift) |
+                            (blue  << BShift);
+                    /* recall that we set ximage->byte_order = MSBFirst above */
+                    if (bpp == 32) {
+                        *dest++ = (char)((pixel >> 24) & 0xff);
+                        *dest++ = (char)((pixel >> 16) & 0xff);
+                        *dest++ = (char)((pixel >>  8) & 0xff);
+                        *dest++ = (char)( pixel        & 0xff);
+                    } else {
+                        /* this assumes bpp == 24 & bits are packed low */
+                        /* (probably need to use RShift, RMask, etc.) */
+                        *dest++ = (char)((pixel >> 16) & 0xff);
+                        *dest++ = (char)((pixel >>  8) & 0xff);
+                        *dest++ = (char)( pixel        & 0xff);
+                    }
+#else
+                    red   = (RShift < 0)? red   << (-RShift) : red   >> RShift;
+                    green = (GShift < 0)? green << (-GShift) : green >> GShift;
+                    blue  = (BShift < 0)? blue  << (-BShift) : blue  >> BShift;
+                    pixel = (red & RMask) | (green & GMask) | (blue & BMask);
+                    /* recall that we set ximage->byte_order = MSBFirst above */
+                    if (bpp == 32) {
+                        *dest++ = (char)((pixel >> 24) & 0xff);
+                        *dest++ = (char)((pixel >> 16) & 0xff);
+                        *dest++ = (char)((pixel >>  8) & 0xff);
+                        *dest++ = (char)( pixel        & 0xff);
+                    } else {
+                        /* GRR BUG */
+                        /* this assumes bpp == 24 & bits are packed low */
+                        /* (probably need to use RShift/RMask/etc. here, too) */
+                        *dest++ = (char)((pixel >> 16) & 0xff);
+                        *dest++ = (char)((pixel >>  8) & 0xff);
+                        *dest++ = (char)( pixel        & 0xff);
+                    }
+#endif
+                }
+            }
+            /* display after every 16 lines */
+            if (((row+1) & 0xf) == 0) {
+                XPutImage(display, window, gc, ximage, 0, (int)lastrow, 0,
+                  (int)lastrow, rpng2_info.width, 16);
+                XFlush(display);
+                lastrow = row + 1;
+            }
+        }
+
+    } else if (depth == 16) {
+        ush red, green, blue;
+
+        for (lastrow = row = startrow;  row < startrow+height;  ++row) {
+            src = rpng2_info.row_pointers[row];
+            if (bg_image)
+                src2 = bg_data + row*bg_rowbytes;
+            dest = ximage->data + row*ximage_rowbytes;
+            if (rpng2_info.channels == 3) {
+                for (i = rpng2_info.width;  i > 0;  --i) {
+                    red   = ((ush)(*src) << 8);
+                    ++src;
+                    green = ((ush)(*src) << 8);
+                    ++src;
+                    blue  = ((ush)(*src) << 8);
+                    ++src;
+                    pixel = ((red   >> RShift) & RMask) |
+                            ((green >> GShift) & GMask) |
+                            ((blue  >> BShift) & BMask);
+                    /* recall that we set ximage->byte_order = MSBFirst above */
+                    *dest++ = (char)((pixel >>  8) & 0xff);
+                    *dest++ = (char)( pixel        & 0xff);
+                }
+            } else /* if (rpng2_info.channels == 4) */ {
+                for (i = rpng2_info.width;  i > 0;  --i) {
+                    r = *src++;
+                    g = *src++;
+                    b = *src++;
+                    a = *src++;
+                    if (bg_image) {
+                        bg_red   = *src2++;
+                        bg_green = *src2++;
+                        bg_blue  = *src2++;
+                    }
+                    if (a == 255) {
+                        red   = ((ush)r << 8);
+                        green = ((ush)g << 8);
+                        blue  = ((ush)b << 8);
+                    } else if (a == 0) {
+                        red   = ((ush)bg_red   << 8);
+                        green = ((ush)bg_green << 8);
+                        blue  = ((ush)bg_blue  << 8);
+                    } else {
+                        /* this macro (from png.h) composites the foreground
+                         * and background values and puts the result back into
+                         * the first argument (== fg byte here:  safe) */
+                        alpha_composite(r, r, a, bg_red);
+                        alpha_composite(g, g, a, bg_green);
+                        alpha_composite(b, b, a, bg_blue);
+                        red   = ((ush)r << 8);
+                        green = ((ush)g << 8);
+                        blue  = ((ush)b << 8);
+                    }
+                    pixel = ((red   >> RShift) & RMask) |
+                            ((green >> GShift) & GMask) |
+                            ((blue  >> BShift) & BMask);
+                    /* recall that we set ximage->byte_order = MSBFirst above */
+                    *dest++ = (char)((pixel >>  8) & 0xff);
+                    *dest++ = (char)( pixel        & 0xff);
+                }
+            }
+            /* display after every 16 lines */
+            if (((row+1) & 0xf) == 0) {
+                XPutImage(display, window, gc, ximage, 0, (int)lastrow, 0,
+                  (int)lastrow, rpng2_info.width, 16);
+                XFlush(display);
+                lastrow = row + 1;
+            }
+        }
+
+    } else /* depth == 8 */ {
+
+        /* GRR:  add 8-bit support */
+
+    }
+
+    Trace((stderr, "calling final XPutImage()\n"))
+    if (lastrow < startrow+height) {
+        XPutImage(display, window, gc, ximage, 0, (int)lastrow, 0,
+          (int)lastrow, rpng2_info.width, rpng2_info.height-lastrow);
+        XFlush(display);
+    }
+
+} /* end function rpng2_x_redisplay_image() */
+
+
+
+
+
+#ifdef FEATURE_LOOP
+
+static void rpng2_x_reload_bg_image(void)
+{
+    char *dest;
+    uch r1, r2, g1, g2, b1, b2;
+    uch r1_inv, r2_inv, g1_inv, g2_inv, b1_inv, b2_inv;
+    int k, hmax, max;
+    int xidx, yidx, yidx_max;
+    int even_odd_vert, even_odd_horiz, even_odd;
+    int invert_gradient2 = (bg[pat].type & 0x08);
+    int invert_column;
+    ulg i, row;
+
+
+    bgscale = (pat == 0)? 8 : bgscale_default;
+    yidx_max = bgscale - 1;
+
+/*---------------------------------------------------------------------------
+    Vertical gradients (ramps) in NxN squares, alternating direction and
+    colors (N == bgscale).
+  ---------------------------------------------------------------------------*/
+
+    if ((bg[pat].type & 0x07) == 0) {
+        uch r1_min  = rgb[bg[pat].rgb1_min].r;
+        uch g1_min  = rgb[bg[pat].rgb1_min].g;
+        uch b1_min  = rgb[bg[pat].rgb1_min].b;
+        uch r2_min  = rgb[bg[pat].rgb2_min].r;
+        uch g2_min  = rgb[bg[pat].rgb2_min].g;
+        uch b2_min  = rgb[bg[pat].rgb2_min].b;
+        int r1_diff = rgb[bg[pat].rgb1_max].r - r1_min;
+        int g1_diff = rgb[bg[pat].rgb1_max].g - g1_min;
+        int b1_diff = rgb[bg[pat].rgb1_max].b - b1_min;
+        int r2_diff = rgb[bg[pat].rgb2_max].r - r2_min;
+        int g2_diff = rgb[bg[pat].rgb2_max].g - g2_min;
+        int b2_diff = rgb[bg[pat].rgb2_max].b - b2_min;
+
+        for (row = 0;  row < rpng2_info.height;  ++row) {
+            yidx = (int)(row % bgscale);
+            even_odd_vert = (int)((row / bgscale) & 1);
+
+            r1 = r1_min + (r1_diff * yidx) / yidx_max;
+            g1 = g1_min + (g1_diff * yidx) / yidx_max;
+            b1 = b1_min + (b1_diff * yidx) / yidx_max;
+            r1_inv = r1_min + (r1_diff * (yidx_max-yidx)) / yidx_max;
+            g1_inv = g1_min + (g1_diff * (yidx_max-yidx)) / yidx_max;
+            b1_inv = b1_min + (b1_diff * (yidx_max-yidx)) / yidx_max;
+
+            r2 = r2_min + (r2_diff * yidx) / yidx_max;
+            g2 = g2_min + (g2_diff * yidx) / yidx_max;
+            b2 = b2_min + (b2_diff * yidx) / yidx_max;
+            r2_inv = r2_min + (r2_diff * (yidx_max-yidx)) / yidx_max;
+            g2_inv = g2_min + (g2_diff * (yidx_max-yidx)) / yidx_max;
+            b2_inv = b2_min + (b2_diff * (yidx_max-yidx)) / yidx_max;
+
+            dest = (char *)bg_data + row*bg_rowbytes;
+            for (i = 0;  i < rpng2_info.width;  ++i) {
+                even_odd_horiz = (int)((i / bgscale) & 1);
+                even_odd = even_odd_vert ^ even_odd_horiz;
+                invert_column =
+                  (even_odd_horiz && (bg[pat].type & 0x10));
+                if (even_odd == 0) {        /* gradient #1 */
+                    if (invert_column) {
+                        *dest++ = r1_inv;
+                        *dest++ = g1_inv;
+                        *dest++ = b1_inv;
+                    } else {
+                        *dest++ = r1;
+                        *dest++ = g1;
+                        *dest++ = b1;
+                    }
+                } else {                    /* gradient #2 */
+                    if ((invert_column && invert_gradient2) ||
+                        (!invert_column && !invert_gradient2))
+                    {
+                        *dest++ = r2;       /* not inverted or */
+                        *dest++ = g2;       /*  doubly inverted */
+                        *dest++ = b2;
+                    } else {
+                        *dest++ = r2_inv;
+                        *dest++ = g2_inv;   /* singly inverted */
+                        *dest++ = b2_inv;
+                    }
+                }
+            }
+        }
+
+/*---------------------------------------------------------------------------
+    Soft gradient-diamonds with scale = bgscale.  Code contributed by Adam
+    M. Costello.
+  ---------------------------------------------------------------------------*/
+
+    } else if ((bg[pat].type & 0x07) == 1) {
+
+        hmax = (bgscale-1)/2;   /* half the max weight of a color */
+        max = 2*hmax;           /* the max weight of a color */
+
+        r1 = rgb[bg[pat].rgb1_max].r;
+        g1 = rgb[bg[pat].rgb1_max].g;
+        b1 = rgb[bg[pat].rgb1_max].b;
+        r2 = rgb[bg[pat].rgb2_max].r;
+        g2 = rgb[bg[pat].rgb2_max].g;
+        b2 = rgb[bg[pat].rgb2_max].b;
+
+        for (row = 0;  row < rpng2_info.height;  ++row) {
+            yidx = (int)(row % bgscale);
+            if (yidx > hmax)
+                yidx = bgscale-1 - yidx;
+            dest = (char *)bg_data + row*bg_rowbytes;
+            for (i = 0;  i < rpng2_info.width;  ++i) {
+                xidx = (int)(i % bgscale);
+                if (xidx > hmax)
+                    xidx = bgscale-1 - xidx;
+                k = xidx + yidx;
+                *dest++ = (k*r1 + (max-k)*r2) / max;
+                *dest++ = (k*g1 + (max-k)*g2) / max;
+                *dest++ = (k*b1 + (max-k)*b2) / max;
+            }
+        }
+
+/*---------------------------------------------------------------------------
+    Radial "starburst" with azimuthal sinusoids; [eventually number of sinu-
+    soids will equal bgscale?].  This one is slow but very cool.  Code con-
+    tributed by Pieter S. van der Meulen (originally in Smalltalk).
+  ---------------------------------------------------------------------------*/
+
+    } else if ((bg[pat].type & 0x07) == 2) {
+        uch ch;
+        int ii, x, y, hw, hh, grayspot;
+        double freq, rotate, saturate, gray, intensity;
+        double angle=0.0, aoffset=0.0, maxDist, dist;
+        double red=0.0, green=0.0, blue=0.0, hue, s, v, f, p, q, t;
+
+        hh = (int)(rpng2_info.height / 2);
+        hw = (int)(rpng2_info.width / 2);
+
+        /* variables for radial waves:
+         *   aoffset:  number of degrees to rotate hue [CURRENTLY NOT USED]
+         *   freq:  number of color beams originating from the center
+         *   grayspot:  size of the graying center area (anti-alias)
+         *   rotate:  rotation of the beams as a function of radius
+         *   saturate:  saturation of beams' shape azimuthally
+         */
+        angle = CLIP(angle, 0.0, 360.0);
+        grayspot = CLIP(bg[pat].bg_gray, 1, (hh + hw));
+        freq = MAX((double)bg[pat].bg_freq, 0.0);
+        saturate = (double)bg[pat].bg_bsat * 0.1;
+        rotate = (double)bg[pat].bg_brot * 0.1;
+        gray = 0.0;
+        intensity = 0.0;
+        maxDist = (double)((hw*hw) + (hh*hh));
+
+        for (row = 0;  row < rpng2_info.height;  ++row) {
+            y = (int)(row - hh);
+            dest = (char *)bg_data + row*bg_rowbytes;
+            for (i = 0;  i < rpng2_info.width;  ++i) {
+                x = (int)(i - hw);
+                angle = (x == 0)? PI_2 : atan((double)y / (double)x);
+                gray = (double)MAX(ABS(y), ABS(x)) / grayspot;
+                gray = MIN(1.0, gray);
+                dist = (double)((x*x) + (y*y)) / maxDist;
+                intensity = cos((angle+(rotate*dist*PI)) * freq) *
+                  gray * saturate;
+                intensity = (MAX(MIN(intensity,1.0),-1.0) + 1.0) * 0.5;
+                hue = (angle + PI) * INV_PI_360 + aoffset;
+                s = gray * ((double)(ABS(x)+ABS(y)) / (double)(hw + hh));
+                s = MIN(MAX(s,0.0), 1.0);
+                v = MIN(MAX(intensity,0.0), 1.0);
+
+                if (s == 0.0) {
+                    ch = (uch)(v * 255.0);
+                    *dest++ = ch;
+                    *dest++ = ch;
+                    *dest++ = ch;
+                } else {
+                    if ((hue < 0.0) || (hue >= 360.0))
+                        hue -= (((int)(hue / 360.0)) * 360.0);
+                    hue /= 60.0;
+                    ii = (int)hue;
+                    f = hue - (double)ii;
+                    p = (1.0 - s) * v;
+                    q = (1.0 - (s * f)) * v;
+                    t = (1.0 - (s * (1.0 - f))) * v;
+                    if      (ii == 0) { red = v; green = t; blue = p; }
+                    else if (ii == 1) { red = q; green = v; blue = p; }
+                    else if (ii == 2) { red = p; green = v; blue = t; }
+                    else if (ii == 3) { red = p; green = q; blue = v; }
+                    else if (ii == 4) { red = t; green = p; blue = v; }
+                    else if (ii == 5) { red = v; green = p; blue = q; }
+                    *dest++ = (uch)(red * 255.0);
+                    *dest++ = (uch)(green * 255.0);
+                    *dest++ = (uch)(blue * 255.0);
+                }
+            }
+        }
+    }
+
+} /* end function rpng2_x_reload_bg_image() */
+
+
+
+
+
+static int is_number(char *p)
+{
+    while (*p) {
+        if (!isdigit(*p))
+            return FALSE;
+        ++p;
+    }
+    return TRUE;
+}
+
+#endif /* FEATURE_LOOP */
+
+
+
+
+
+static void rpng2_x_cleanup(void)
+{
+    if (bg_image && bg_data) {
+        free(bg_data);
+        bg_data = NULL;
+    }
+
+    if (rpng2_info.image_data) {
+        free(rpng2_info.image_data);
+        rpng2_info.image_data = NULL;
+    }
+
+    if (rpng2_info.row_pointers) {
+        free(rpng2_info.row_pointers);
+        rpng2_info.row_pointers = NULL;
+    }
+
+    if (ximage) {
+        if (ximage->data) {
+            free(ximage->data);           /* we allocated it, so we free it */
+            ximage->data = (char *)NULL;  /*  instead of XDestroyImage() */
+        }
+        XDestroyImage(ximage);
+        ximage = NULL;
+    }
+
+    if (have_gc)
+        XFreeGC(display, gc);
+
+    if (have_window)
+        XDestroyWindow(display, window);
+
+    if (have_colormap)
+        XFreeColormap(display, colormap);
+
+    if (have_nondefault_visual)
+        XFree(visual_list);
+}
+
+
+
+
+
+static int rpng2_x_msb(ulg u32val)
+{
+    int i;
+
+    for (i = 31;  i >= 0;  --i) {
+        if (u32val & 0x80000000L)
+            break;
+        u32val <<= 1;
+    }
+    return i;
+}
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/wpng.c b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/wpng.c
index 30372a3..a06e352 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/wpng.c
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/wpng.c
@@ -1,853 +1,853 @@
-/*---------------------------------------------------------------------------

-

-   wpng - simple PNG-writing program                                 wpng.c

-

-   This program converts certain NetPBM binary files (grayscale and RGB,

-   maxval = 255) to PNG.  Non-interlaced PNGs are written progressively;

-   interlaced PNGs are read and written in one memory-intensive blast.

-

-   Thanks to Jean-loup Gailly for providing the necessary trick to read

-   interactive text from the keyboard while stdin is redirected.  Thanks

-   to Cosmin Truta for Cygwin fixes.

-

-   NOTE:  includes provisional support for PNM type "8" (portable alphamap)

-          images, presumed to be a 32-bit interleaved RGBA format; no pro-

-          vision for possible interleaved grayscale+alpha (16-bit) format.

-          THIS IS UNLIKELY TO BECOME AN OFFICIAL NETPBM ALPHA FORMAT!

-

-   to do:

-    - delete output file if quit before calling any writepng routines

-    - process backspace with -text option under DOS/Win? (currently get ^H)

-

-  ---------------------------------------------------------------------------

-

-   Changelog:

-    - 1.01:  initial public release

-    - 1.02:  modified to allow abbreviated options

-    - 1.03:  removed extraneous character from usage screen; fixed bug in

-              command-line parsing

-    - 1.04:  fixed DOS/OS2/Win32 detection, including partial Cygwin fix

-              (see http://home.att.net/~perlspinr/diffs/GregBook_cygwin.diff)

-    - 2.00:  dual-licensed (added GNU GPL)

-

-        [REPORTED BUG (win32 only):  "contrib/gregbook/wpng.c - cmd line

-         dose not work!  In order to do something useful I needed to redirect

-         both input and output, with cygwin and with bcc32 as well.  Under

-         Linux, the same wpng appears to work fine.  I don't know what is

-         the problem."]

-

-  ---------------------------------------------------------------------------

-

-      Copyright (c) 1998-2007 Greg Roelofs.  All rights reserved.

-

-      This software is provided "as is," without warranty of any kind,

-      express or implied.  In no event shall the author or contributors

-      be held liable for any damages arising in any way from the use of

-      this software.

-

-      The contents of this file are DUAL-LICENSED.  You may modify and/or

-      redistribute this software according to the terms of one of the

-      following two licenses (at your option):

-

-

-      LICENSE 1 ("BSD-like with advertising clause"):

-

-      Permission is granted to anyone to use this software for any purpose,

-      including commercial applications, and to alter it and redistribute

-      it freely, subject to the following restrictions:

-

-      1. Redistributions of source code must retain the above copyright

-         notice, disclaimer, and this list of conditions.

-      2. Redistributions in binary form must reproduce the above copyright

-         notice, disclaimer, and this list of conditions in the documenta-

-         tion and/or other materials provided with the distribution.

-      3. All advertising materials mentioning features or use of this

-         software must display the following acknowledgment:

-

-            This product includes software developed by Greg Roelofs

-            and contributors for the book, "PNG: The Definitive Guide,"

-            published by O'Reilly and Associates.

-

-

-      LICENSE 2 (GNU GPL v2 or later):

-

-      This program is free software; you can redistribute it and/or modify

-      it under the terms of the GNU General Public License as published by

-      the Free Software Foundation; either version 2 of the License, or

-      (at your option) any later version.

-

-      This program is distributed in the hope that it will be useful,

-      but WITHOUT ANY WARRANTY; without even the implied warranty of

-      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

-      GNU General Public License for more details.

-

-      You should have received a copy of the GNU General Public License

-      along with this program; if not, write to the Free Software Foundation,

-      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

-

-  ---------------------------------------------------------------------------*/

-

-#define PROGNAME  "wpng"

-#define VERSION   "2.00 of 2 June 2007"

-#define APPNAME   "Simple PGM/PPM/PAM to PNG Converter"

-

-#if defined(__MSDOS__) || defined(__OS2__)

-#  define DOS_OS2_W32

-#elif defined(WIN32) || defined(_WIN32) || defined(__WIN32__)

-#  ifndef __GNUC__   /* treat Win32 native ports of gcc as Unix environments */

-#    define DOS_OS2_W32

-#  endif

-#endif

-

-#include <stdio.h>

-#include <stdlib.h>

-#include <string.h>

-#include <setjmp.h>     /* for jmpbuf declaration in writepng.h */

-#include <time.h>

-

-#ifdef DOS_OS2_W32

-#  include <io.h>       /* for isatty(), setmode() prototypes */

-#  include <fcntl.h>    /* O_BINARY for fdopen() without text translation */

-#  ifdef __EMX__

-#    ifndef getch

-#      define getch() _read_kbd(0, 1, 0)    /* need getche() */

-#    endif

-#  else /* !__EMX__ */

-#    ifdef __GO32__

-#      include <pc.h>

-#      define getch() getkey()  /* GRR:  need getche() */

-#    else

-#      include <conio.h>        /* for getche() console input */

-#    endif

-#  endif /* ?__EMX__ */

-#  define FGETS(buf,len,stream)  dos_kbd_gets(buf,len)

-#else

-#  include <unistd.h>           /* for isatty() prototype */

-#  define FGETS fgets

-#endif

-

-/* #define DEBUG  :  this enables the Trace() macros */

-

-/* #define FORBID_LATIN1_CTRL  :  this requires the user to re-enter any

-   text that includes control characters discouraged by the PNG spec; text

-   that includes an escape character (27) must be re-entered regardless */

-

-#include "writepng.h"   /* typedefs, common macros, writepng prototypes */

-

-

-

-/* local prototypes */

-

-static int  wpng_isvalid_latin1(uch *p, int len);

-static void wpng_cleanup(void);

-

-#ifdef DOS_OS2_W32

-   static char *dos_kbd_gets(char *buf, int len);

-#endif

-

-

-

-static mainprog_info wpng_info;   /* lone global */

-

-

-

-int main(int argc, char **argv)

-{

-#ifndef DOS_OS2_W32

-    FILE *keybd;

-#endif

-#ifdef sgi

-    FILE *tmpfile;      /* or we could just use keybd, since no overlap */

-    char tmpline[80];

-#endif

-    char *inname = NULL, outname[256];

-    char *p, pnmchar, pnmline[256];

-    char *bgstr, *textbuf = NULL;

-    ulg rowbytes;

-    int rc, len = 0;

-    int error = 0;

-    int text = FALSE;

-    int maxval;

-    double LUT_exponent;                /* just the lookup table */

-    double CRT_exponent = 2.2;          /* just the monitor */

-    double default_display_exponent;    /* whole display system */

-    double default_gamma = 0.0;

-

-

-    wpng_info.infile = NULL;

-    wpng_info.outfile = NULL;

-    wpng_info.image_data = NULL;

-    wpng_info.row_pointers = NULL;

-    wpng_info.filter = FALSE;

-    wpng_info.interlaced = FALSE;

-    wpng_info.have_bg = FALSE;

-    wpng_info.have_time = FALSE;

-    wpng_info.have_text = 0;

-    wpng_info.gamma = 0.0;

-

-

-    /* First get the default value for our display-system exponent, i.e.,

-     * the product of the CRT exponent and the exponent corresponding to

-     * the frame-buffer's lookup table (LUT), if any.  If the PNM image

-     * looks correct on the user's display system, its file gamma is the

-     * inverse of this value.  (Note that this is not an exhaustive list

-     * of LUT values--e.g., OpenStep has a lot of weird ones--but it should

-     * cover 99% of the current possibilities.  This section must ensure

-     * that default_display_exponent is positive.) */

-

-#if defined(NeXT)

-    /* third-party utilities can modify the default LUT exponent */

-    LUT_exponent = 1.0 / 2.2;

-    /*

-    if (some_next_function_that_returns_gamma(&next_gamma))

-        LUT_exponent = 1.0 / next_gamma;

-     */

-#elif defined(sgi)

-    LUT_exponent = 1.0 / 1.7;

-    /* there doesn't seem to be any documented function to

-     * get the "gamma" value, so we do it the hard way */

-    tmpfile = fopen("/etc/config/system.glGammaVal", "r");

-    if (tmpfile) {

-        double sgi_gamma;

-

-        fgets(tmpline, 80, tmpfile);

-        fclose(tmpfile);

-        sgi_gamma = atof(tmpline);

-        if (sgi_gamma > 0.0)

-            LUT_exponent = 1.0 / sgi_gamma;

-    }

-#elif defined(Macintosh)

-    LUT_exponent = 1.8 / 2.61;

-    /*

-    if (some_mac_function_that_returns_gamma(&mac_gamma))

-        LUT_exponent = mac_gamma / 2.61;

-     */

-#else

-    LUT_exponent = 1.0;   /* assume no LUT:  most PCs */

-#endif

-

-    /* the defaults above give 1.0, 1.3, 1.5 and 2.2, respectively: */

-    default_display_exponent = LUT_exponent * CRT_exponent;

-

-

-    /* If the user has set the SCREEN_GAMMA environment variable as suggested

-     * (somewhat imprecisely) in the libpng documentation, use that; otherwise

-     * use the default value we just calculated.  Either way, the user may

-     * override this via a command-line option. */

-

-    if ((p = getenv("SCREEN_GAMMA")) != NULL) {

-        double exponent = atof(p);

-

-        if (exponent > 0.0)

-            default_gamma = 1.0 / exponent;

-    }

-

-    if (default_gamma == 0.0)

-        default_gamma = 1.0 / default_display_exponent;

-

-

-    /* Now parse the command line for options and the PNM filename. */

-

-    while (*++argv && !error) {

-        if (!strncmp(*argv, "-i", 2)) {

-            wpng_info.interlaced = TRUE;

-        } else if (!strncmp(*argv, "-time", 3)) {

-            wpng_info.modtime = time(NULL);

-            wpng_info.have_time = TRUE;

-        } else if (!strncmp(*argv, "-text", 3)) {

-            text = TRUE;

-        } else if (!strncmp(*argv, "-gamma", 2)) {

-            if (!*++argv)

-                ++error;

-            else {

-                wpng_info.gamma = atof(*argv);

-                if (wpng_info.gamma <= 0.0)

-                    ++error;

-                else if (wpng_info.gamma > 1.01)

-                    fprintf(stderr, PROGNAME

-                      " warning:  file gammas are usually less than 1.0\n");

-            }

-        } else if (!strncmp(*argv, "-bgcolor", 4)) {

-            if (!*++argv)

-                ++error;

-            else {

-                bgstr = *argv;

-                if (strlen(bgstr) != 7 || bgstr[0] != '#')

-                    ++error;

-                else {

-                    unsigned r, g, b;  /* this way quiets compiler warnings */

-

-                    sscanf(bgstr+1, "%2x%2x%2x", &r, &g, &b);

-                    wpng_info.bg_red   = (uch)r;

-                    wpng_info.bg_green = (uch)g;

-                    wpng_info.bg_blue  = (uch)b;

-                    wpng_info.have_bg = TRUE;

-                }

-            }

-        } else {

-            if (**argv != '-') {

-                inname = *argv;

-                if (argv[1])   /* shouldn't be any more args after filename */

-                    ++error;

-            } else

-                ++error;   /* not expecting any other options */

-        }

-    }

-

-

-    /* open the input and output files, or register an error and abort */

-

-    if (!inname) {

-        if (isatty(0)) {

-            fprintf(stderr, PROGNAME

-              ":  must give input filename or provide image data via stdin\n");

-            ++error;

-        } else {

-#ifdef DOS_OS2_W32

-            /* some buggy C libraries require BOTH setmode() and fdopen(bin) */

-            setmode(fileno(stdin), O_BINARY);

-            setmode(fileno(stdout), O_BINARY);

-#endif

-            if ((wpng_info.infile = fdopen(fileno(stdin), "rb")) == NULL) {

-                fprintf(stderr, PROGNAME

-                  ":  unable to reopen stdin in binary mode\n");

-                ++error;

-            } else

-            if ((wpng_info.outfile = fdopen(fileno(stdout), "wb")) == NULL) {

-                fprintf(stderr, PROGNAME

-                  ":  unable to reopen stdout in binary mode\n");

-                fclose(wpng_info.infile);

-                ++error;

-            } else

-                wpng_info.filter = TRUE;

-        }

-    } else if ((len = strlen(inname)) > 250) {

-        fprintf(stderr, PROGNAME ":  input filename is too long [%d chars]\n",

-          len);

-        ++error;

-    } else if (!(wpng_info.infile = fopen(inname, "rb"))) {

-        fprintf(stderr, PROGNAME ":  can't open input file [%s]\n", inname);

-        ++error;

-    }

-

-    if (!error) {

-        fgets(pnmline, 256, wpng_info.infile);

-        if (pnmline[0] != 'P' || ((pnmchar = pnmline[1]) != '5' &&

-            pnmchar != '6' && pnmchar != '8'))

-        {

-            fprintf(stderr, PROGNAME

-              ":  input file [%s] is not a binary PGM, PPM or PAM file\n",

-              inname);

-            ++error;

-        } else {

-            wpng_info.pnmtype = (int)(pnmchar - '0');

-            if (wpng_info.pnmtype != 8)

-                wpng_info.have_bg = FALSE;  /* no need for bg if opaque */

-            do {

-                fgets(pnmline, 256, wpng_info.infile);  /* lose any comments */

-            } while (pnmline[0] == '#');

-            sscanf(pnmline, "%ld %ld", &wpng_info.width, &wpng_info.height);

-            do {

-                fgets(pnmline, 256, wpng_info.infile);  /* more comment lines */

-            } while (pnmline[0] == '#');

-            sscanf(pnmline, "%d", &maxval);

-            if (wpng_info.width <= 0L || wpng_info.height <= 0L ||

-                maxval != 255)

-            {

-                fprintf(stderr, PROGNAME

-                  ":  only positive width/height, maxval == 255 allowed \n");

-                ++error;

-            }

-            wpng_info.sample_depth = 8;  /* <==> maxval 255 */

-

-            if (!wpng_info.filter) {

-                /* make outname from inname */

-                if ((p = strrchr(inname, '.')) == NULL ||

-                    (p - inname) != (len - 4))

-                {

-                    strcpy(outname, inname);

-                    strcpy(outname+len, ".png");

-                } else {

-                    len -= 4;

-                    strncpy(outname, inname, len);

-                    strcpy(outname+len, ".png");

-                }

-                /* check if outname already exists; if not, open */

-                if ((wpng_info.outfile = fopen(outname, "rb")) != NULL) {

-                    fprintf(stderr, PROGNAME ":  output file exists [%s]\n",

-                      outname);

-                    fclose(wpng_info.outfile);

-                    ++error;

-                } else if (!(wpng_info.outfile = fopen(outname, "wb"))) {

-                    fprintf(stderr, PROGNAME ":  can't open output file [%s]\n",

-                      outname);

-                    ++error;

-                }

-            }

-        }

-        if (error) {

-            fclose(wpng_info.infile);

-            wpng_info.infile = NULL;

-            if (wpng_info.filter) {

-                fclose(wpng_info.outfile);

-                wpng_info.outfile = NULL;

-            }

-        }

-    }

-

-

-    /* if we had any errors, print usage and die horrible death...arrr! */

-

-    if (error) {

-        fprintf(stderr, "\n%s %s:  %s\n", PROGNAME, VERSION, APPNAME);

-        writepng_version_info();

-        fprintf(stderr, "\n"

-"Usage:  %s [-gamma exp] [-bgcolor bg] [-text] [-time] [-interlace] pnmfile\n"

-"or: ... | %s [-gamma exp] [-bgcolor bg] [-text] [-time] [-interlace] | ...\n"

-         "    exp \ttransfer-function exponent (``gamma'') of the image in\n"

-         "\t\t  floating-point format (e.g., ``%.5f''); if image looks\n"

-         "\t\t  correct on given display system, image gamma is equal to\n"

-         "\t\t  inverse of display-system exponent, i.e., 1 / (LUT * CRT)\n"

-         "\t\t  (where LUT = lookup-table exponent and CRT = CRT exponent;\n"

-         "\t\t  first varies, second is usually 2.2, all are positive)\n"

-         "    bg  \tdesired background color for alpha-channel images, in\n"

-         "\t\t  7-character hex RGB format (e.g., ``#ff7700'' for orange:\n"

-         "\t\t  same as HTML colors)\n"

-         "    -text\tprompt interactively for text info (tEXt chunks)\n"

-         "    -time\tinclude a tIME chunk (last modification time)\n"

-         "    -interlace\twrite interlaced PNG image\n"

-         "\n"

-"pnmfile or stdin must be a binary PGM (`P5'), PPM (`P6') or (extremely\n"

-"unofficial and unsupported!) PAM (`P8') file.  Currently it is required\n"

-"to have maxval == 255 (i.e., no scaling).  If pnmfile is specified, it\n"

-"is converted to the corresponding PNG file with the same base name but a\n"

-"``.png'' extension; files read from stdin are converted and sent to stdout.\n"

-"The conversion is progressive (low memory usage) unless interlacing is\n"

-"requested; in that case the whole image will be buffered in memory and\n"

-"written in one call.\n"

-         "\n", PROGNAME, PROGNAME, default_gamma);

-        exit(1);

-    }

-

-

-    /* prepare the text buffers for libpng's use; note that even though

-     * PNG's png_text struct includes a length field, we don't have to fill

-     * it out */

-

-    if (text &&

-#ifndef DOS_OS2_W32

-        (keybd = fdopen(fileno(stderr), "r")) != NULL &&

-#endif

-        (textbuf = (char *)malloc((5 + 9)*75)) != NULL)

-    {

-        int i, valid, result;

-

-        fprintf(stderr,

-          "Enter text info (no more than 72 characters per line);\n");

-        fprintf(stderr, "to skip a field, hit the <Enter> key.\n");

-        /* note:  just <Enter> leaves len == 1 */

-

-        do {

-            valid = TRUE;

-            p = textbuf + TEXT_TITLE_OFFSET;

-            fprintf(stderr, "  Title: ");

-            fflush(stderr);

-            if (FGETS(p, 74, keybd) && (len = strlen(p)) > 1) {

-                if (p[len-1] == '\n')

-                    p[--len] = '\0';

-                wpng_info.title = p;

-                wpng_info.have_text |= TEXT_TITLE;

-                if ((result = wpng_isvalid_latin1((uch *)p, len)) >= 0) {

-                    fprintf(stderr, "    " PROGNAME " warning:  character code"

-                      " %u is %sdiscouraged by the PNG\n    specification "

-                      "[first occurrence was at character position #%d]\n",

-                      (unsigned)p[result], (p[result] == 27)? "strongly " : "",

-                      result+1);

-                    fflush(stderr);

-#ifdef FORBID_LATIN1_CTRL

-                    wpng_info.have_text &= ~TEXT_TITLE;

-                    valid = FALSE;

-#else

-                    if (p[result] == 27) {    /* escape character */

-                        wpng_info.have_text &= ~TEXT_TITLE;

-                        valid = FALSE;

-                    }

-#endif

-                }

-            }

-        } while (!valid);

-

-        do {

-            valid = TRUE;

-            p = textbuf + TEXT_AUTHOR_OFFSET;

-            fprintf(stderr, "  Author: ");

-            fflush(stderr);

-            if (FGETS(p, 74, keybd) && (len = strlen(p)) > 1) {

-                if (p[len-1] == '\n')

-                    p[--len] = '\0';

-                wpng_info.author = p;

-                wpng_info.have_text |= TEXT_AUTHOR;

-                if ((result = wpng_isvalid_latin1((uch *)p, len)) >= 0) {

-                    fprintf(stderr, "    " PROGNAME " warning:  character code"

-                      " %u is %sdiscouraged by the PNG\n    specification "

-                      "[first occurrence was at character position #%d]\n",

-                      (unsigned)p[result], (p[result] == 27)? "strongly " : "",

-                      result+1);

-                    fflush(stderr);

-#ifdef FORBID_LATIN1_CTRL

-                    wpng_info.have_text &= ~TEXT_AUTHOR;

-                    valid = FALSE;

-#else

-                    if (p[result] == 27) {    /* escape character */

-                        wpng_info.have_text &= ~TEXT_AUTHOR;

-                        valid = FALSE;

-                    }

-#endif

-                }

-            }

-        } while (!valid);

-

-        do {

-            valid = TRUE;

-            p = textbuf + TEXT_DESC_OFFSET;

-            fprintf(stderr, "  Description (up to 9 lines):\n");

-            for (i = 1;  i < 10;  ++i) {

-                fprintf(stderr, "    [%d] ", i);

-                fflush(stderr);

-                if (FGETS(p, 74, keybd) && (len = strlen(p)) > 1)

-                    p += len;   /* now points at NULL; char before is newline */

-                else

-                    break;

-            }

-            if ((len = p - (textbuf + TEXT_DESC_OFFSET)) > 1) {

-                if (p[-1] == '\n') {

-                    p[-1] = '\0';

-                    --len;

-                }

-                wpng_info.desc = textbuf + TEXT_DESC_OFFSET;

-                wpng_info.have_text |= TEXT_DESC;

-                p = textbuf + TEXT_DESC_OFFSET;

-                if ((result = wpng_isvalid_latin1((uch *)p, len)) >= 0) {

-                    fprintf(stderr, "    " PROGNAME " warning:  character code"

-                      " %u is %sdiscouraged by the PNG\n    specification "

-                      "[first occurrence was at character position #%d]\n",

-                      (unsigned)p[result], (p[result] == 27)? "strongly " : "",

-                      result+1);

-                    fflush(stderr);

-#ifdef FORBID_LATIN1_CTRL

-                    wpng_info.have_text &= ~TEXT_DESC;

-                    valid = FALSE;

-#else

-                    if (p[result] == 27) {    /* escape character */

-                        wpng_info.have_text &= ~TEXT_DESC;

-                        valid = FALSE;

-                    }

-#endif

-                }

-            }

-        } while (!valid);

-

-        do {

-            valid = TRUE;

-            p = textbuf + TEXT_COPY_OFFSET;

-            fprintf(stderr, "  Copyright: ");

-            fflush(stderr);

-            if (FGETS(p, 74, keybd) && (len = strlen(p)) > 1) {

-                if (p[len-1] == '\n')

-                    p[--len] = '\0';

-                wpng_info.copyright = p;

-                wpng_info.have_text |= TEXT_COPY;

-                if ((result = wpng_isvalid_latin1((uch *)p, len)) >= 0) {

-                    fprintf(stderr, "    " PROGNAME " warning:  character code"

-                      " %u is %sdiscouraged by the PNG\n    specification "

-                      "[first occurrence was at character position #%d]\n",

-                      (unsigned)p[result], (p[result] == 27)? "strongly " : "",

-                      result+1);

-                    fflush(stderr);

-#ifdef FORBID_LATIN1_CTRL

-                    wpng_info.have_text &= ~TEXT_COPY;

-                    valid = FALSE;

-#else

-                    if (p[result] == 27) {    /* escape character */

-                        wpng_info.have_text &= ~TEXT_COPY;

-                        valid = FALSE;

-                    }

-#endif

-                }

-            }

-        } while (!valid);

-

-        do {

-            valid = TRUE;

-            p = textbuf + TEXT_EMAIL_OFFSET;

-            fprintf(stderr, "  E-mail: ");

-            fflush(stderr);

-            if (FGETS(p, 74, keybd) && (len = strlen(p)) > 1) {

-                if (p[len-1] == '\n')

-                    p[--len] = '\0';

-                wpng_info.email = p;

-                wpng_info.have_text |= TEXT_EMAIL;

-                if ((result = wpng_isvalid_latin1((uch *)p, len)) >= 0) {

-                    fprintf(stderr, "    " PROGNAME " warning:  character code"

-                      " %u is %sdiscouraged by the PNG\n    specification "

-                      "[first occurrence was at character position #%d]\n",

-                      (unsigned)p[result], (p[result] == 27)? "strongly " : "",

-                      result+1);

-                    fflush(stderr);

-#ifdef FORBID_LATIN1_CTRL

-                    wpng_info.have_text &= ~TEXT_EMAIL;

-                    valid = FALSE;

-#else

-                    if (p[result] == 27) {    /* escape character */

-                        wpng_info.have_text &= ~TEXT_EMAIL;

-                        valid = FALSE;

-                    }

-#endif

-                }

-            }

-        } while (!valid);

-

-        do {

-            valid = TRUE;

-            p = textbuf + TEXT_URL_OFFSET;

-            fprintf(stderr, "  URL: ");

-            fflush(stderr);

-            if (FGETS(p, 74, keybd) && (len = strlen(p)) > 1) {

-                if (p[len-1] == '\n')

-                    p[--len] = '\0';

-                wpng_info.url = p;

-                wpng_info.have_text |= TEXT_URL;

-                if ((result = wpng_isvalid_latin1((uch *)p, len)) >= 0) {

-                    fprintf(stderr, "    " PROGNAME " warning:  character code"

-                      " %u is %sdiscouraged by the PNG\n    specification "

-                      "[first occurrence was at character position #%d]\n",

-                      (unsigned)p[result], (p[result] == 27)? "strongly " : "",

-                      result+1);

-                    fflush(stderr);

-#ifdef FORBID_LATIN1_CTRL

-                    wpng_info.have_text &= ~TEXT_URL;

-                    valid = FALSE;

-#else

-                    if (p[result] == 27) {    /* escape character */

-                        wpng_info.have_text &= ~TEXT_URL;

-                        valid = FALSE;

-                    }

-#endif

-                }

-            }

-        } while (!valid);

-

-#ifndef DOS_OS2_W32

-        fclose(keybd);

-#endif

-

-    } else if (text) {

-        fprintf(stderr, PROGNAME ":  unable to allocate memory for text\n");

-        text = FALSE;

-        wpng_info.have_text = 0;

-    }

-

-

-    /* allocate libpng stuff, initialize transformations, write pre-IDAT data */

-

-    if ((rc = writepng_init(&wpng_info)) != 0) {

-        switch (rc) {

-            case 2:

-                fprintf(stderr, PROGNAME

-                  ":  libpng initialization problem (longjmp)\n");

-                break;

-            case 4:

-                fprintf(stderr, PROGNAME ":  insufficient memory\n");

-                break;

-            case 11:

-                fprintf(stderr, PROGNAME

-                  ":  internal logic error (unexpected PNM type)\n");

-                break;

-            default:

-                fprintf(stderr, PROGNAME

-                  ":  unknown writepng_init() error\n");

-                break;

-        }

-        exit(rc);

-    }

-

-

-    /* free textbuf, since it's a completely local variable and all text info

-     * has just been written to the PNG file */

-

-    if (text && textbuf) {

-        free(textbuf);

-        textbuf = NULL;

-    }

-

-

-    /* calculate rowbytes on basis of image type; note that this becomes much

-     * more complicated if we choose to support PBM type, ASCII PNM types, or

-     * 16-bit-per-sample binary data [currently not an official NetPBM type] */

-

-    if (wpng_info.pnmtype == 5)

-        rowbytes = wpng_info.width;

-    else if (wpng_info.pnmtype == 6)

-        rowbytes = wpng_info.width * 3;

-    else /* if (wpng_info.pnmtype == 8) */

-        rowbytes = wpng_info.width * 4;

-

-

-    /* read and write the image, either in its entirety (if writing interlaced

-     * PNG) or row by row (if non-interlaced) */

-

-    fprintf(stderr, "Encoding image data...\n");

-    fflush(stderr);

-

-    if (wpng_info.interlaced) {

-        long i;

-        ulg bytes;

-        ulg image_bytes = rowbytes * wpng_info.height;   /* overflow? */

-

-        wpng_info.image_data = (uch *)malloc(image_bytes);

-        wpng_info.row_pointers = (uch **)malloc(wpng_info.height*sizeof(uch *));

-        if (wpng_info.image_data == NULL || wpng_info.row_pointers == NULL) {

-            fprintf(stderr, PROGNAME ":  insufficient memory for image data\n");

-            writepng_cleanup(&wpng_info);

-            wpng_cleanup();

-            exit(5);

-        }

-        for (i = 0;  i < wpng_info.height;  ++i)

-            wpng_info.row_pointers[i] = wpng_info.image_data + i*rowbytes;

-        bytes = fread(wpng_info.image_data, 1, image_bytes, wpng_info.infile);

-        if (bytes != image_bytes) {

-            fprintf(stderr, PROGNAME ":  expected %lu bytes, got %lu bytes\n",

-              image_bytes, bytes);

-            fprintf(stderr, "  (continuing anyway)\n");

-        }

-        if (writepng_encode_image(&wpng_info) != 0) {

-            fprintf(stderr, PROGNAME

-              ":  libpng problem (longjmp) while writing image data\n");

-            writepng_cleanup(&wpng_info);

-            wpng_cleanup();

-            exit(2);

-        }

-

-    } else /* not interlaced:  write progressively (row by row) */ {

-        long j;

-        ulg bytes;

-

-        wpng_info.image_data = (uch *)malloc(rowbytes);

-        if (wpng_info.image_data == NULL) {

-            fprintf(stderr, PROGNAME ":  insufficient memory for row data\n");

-            writepng_cleanup(&wpng_info);

-            wpng_cleanup();

-            exit(5);

-        }

-        error = 0;

-        for (j = wpng_info.height;  j > 0L;  --j) {

-            bytes = fread(wpng_info.image_data, 1, rowbytes, wpng_info.infile);

-            if (bytes != rowbytes) {

-                fprintf(stderr, PROGNAME

-                  ":  expected %lu bytes, got %lu bytes (row %ld)\n", rowbytes,

-                  bytes, wpng_info.height-j);

-                ++error;

-                break;

-            }

-            if (writepng_encode_row(&wpng_info) != 0) {

-                fprintf(stderr, PROGNAME

-                  ":  libpng problem (longjmp) while writing row %ld\n",

-                  wpng_info.height-j);

-                ++error;

-                break;

-            }

-        }

-        if (error) {

-            writepng_cleanup(&wpng_info);

-            wpng_cleanup();

-            exit(2);

-        }

-        if (writepng_encode_finish(&wpng_info) != 0) {

-            fprintf(stderr, PROGNAME ":  error on final libpng call\n");

-            writepng_cleanup(&wpng_info);

-            wpng_cleanup();

-            exit(2);

-        }

-    }

-

-

-    /* OK, we're done (successfully):  clean up all resources and quit */

-

-    fprintf(stderr, "Done.\n");

-    fflush(stderr);

-

-    writepng_cleanup(&wpng_info);

-    wpng_cleanup();

-

-    return 0;

-}

-

-

-

-

-

-static int wpng_isvalid_latin1(uch *p, int len)

-{

-    int i, result = -1;

-

-    for (i = 0;  i < len;  ++i) {

-        if (p[i] == 10 || (p[i] > 31 && p[i] < 127) || p[i] > 160)

-            continue;           /* character is completely OK */

-        if (result < 0 || (p[result] != 27 && p[i] == 27))

-            result = i;         /* mark location of first questionable one */

-    }                           /*  or of first escape character (bad) */

-

-    return result;

-}

-

-

-

-

-

-static void wpng_cleanup(void)

-{

-    if (wpng_info.outfile) {

-        fclose(wpng_info.outfile);

-        wpng_info.outfile = NULL;

-    }

-

-    if (wpng_info.infile) {

-        fclose(wpng_info.infile);

-        wpng_info.infile = NULL;

-    }

-

-    if (wpng_info.image_data) {

-        free(wpng_info.image_data);

-        wpng_info.image_data = NULL;

-    }

-

-    if (wpng_info.row_pointers) {

-        free(wpng_info.row_pointers);

-        wpng_info.row_pointers = NULL;

-    }

-}

-

-

-

-

-#ifdef DOS_OS2_W32

-

-static char *dos_kbd_gets(char *buf, int len)

-{

-    int ch, count=0;

-

-    do {

-        buf[count++] = ch = getche();

-    } while (ch != '\r' && count < len-1);

-

-    buf[count--] = '\0';        /* terminate string */

-    if (buf[count] == '\r')     /* Enter key makes CR, so change to newline */

-        buf[count] = '\n';

-

-    fprintf(stderr, "\n");      /* Enter key does *not* cause a newline */

-    fflush(stderr);

-

-    return buf;

-}

-

-#endif /* DOS_OS2_W32 */

+/*---------------------------------------------------------------------------
+
+   wpng - simple PNG-writing program                                 wpng.c
+
+   This program converts certain NetPBM binary files (grayscale and RGB,
+   maxval = 255) to PNG.  Non-interlaced PNGs are written progressively;
+   interlaced PNGs are read and written in one memory-intensive blast.
+
+   Thanks to Jean-loup Gailly for providing the necessary trick to read
+   interactive text from the keyboard while stdin is redirected.  Thanks
+   to Cosmin Truta for Cygwin fixes.
+
+   NOTE:  includes provisional support for PNM type "8" (portable alphamap)
+          images, presumed to be a 32-bit interleaved RGBA format; no pro-
+          vision for possible interleaved grayscale+alpha (16-bit) format.
+          THIS IS UNLIKELY TO BECOME AN OFFICIAL NETPBM ALPHA FORMAT!
+
+   to do:
+    - delete output file if quit before calling any writepng routines
+    - process backspace with -text option under DOS/Win? (currently get ^H)
+
+  ---------------------------------------------------------------------------
+
+   Changelog:
+    - 1.01:  initial public release
+    - 1.02:  modified to allow abbreviated options
+    - 1.03:  removed extraneous character from usage screen; fixed bug in
+              command-line parsing
+    - 1.04:  fixed DOS/OS2/Win32 detection, including partial Cygwin fix
+              (see http://home.att.net/~perlspinr/diffs/GregBook_cygwin.diff)
+    - 2.00:  dual-licensed (added GNU GPL)
+
+        [REPORTED BUG (win32 only):  "contrib/gregbook/wpng.c - cmd line
+         dose not work!  In order to do something useful I needed to redirect
+         both input and output, with cygwin and with bcc32 as well.  Under
+         Linux, the same wpng appears to work fine.  I don't know what is
+         the problem."]
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-2007 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      The contents of this file are DUAL-LICENSED.  You may modify and/or
+      redistribute this software according to the terms of one of the
+      following two licenses (at your option):
+
+
+      LICENSE 1 ("BSD-like with advertising clause"):
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+
+      LICENSE 2 (GNU GPL v2 or later):
+
+      This program is free software; you can redistribute it and/or modify
+      it under the terms of the GNU General Public License as published by
+      the Free Software Foundation; either version 2 of the License, or
+      (at your option) any later version.
+
+      This program is distributed in the hope that it will be useful,
+      but WITHOUT ANY WARRANTY; without even the implied warranty of
+      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+      GNU General Public License for more details.
+
+      You should have received a copy of the GNU General Public License
+      along with this program; if not, write to the Free Software Foundation,
+      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+  ---------------------------------------------------------------------------*/
+
+#define PROGNAME  "wpng"
+#define VERSION   "2.00 of 2 June 2007"
+#define APPNAME   "Simple PGM/PPM/PAM to PNG Converter"
+
+#if defined(__MSDOS__) || defined(__OS2__)
+#  define DOS_OS2_W32
+#elif defined(WIN32) || defined(_WIN32) || defined(__WIN32__)
+#  ifndef __GNUC__   /* treat Win32 native ports of gcc as Unix environments */
+#    define DOS_OS2_W32
+#  endif
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <setjmp.h>     /* for jmpbuf declaration in writepng.h */
+#include <time.h>
+
+#ifdef DOS_OS2_W32
+#  include <io.h>       /* for isatty(), setmode() prototypes */
+#  include <fcntl.h>    /* O_BINARY for fdopen() without text translation */
+#  ifdef __EMX__
+#    ifndef getch
+#      define getch() _read_kbd(0, 1, 0)    /* need getche() */
+#    endif
+#  else /* !__EMX__ */
+#    ifdef __GO32__
+#      include <pc.h>
+#      define getch() getkey()  /* GRR:  need getche() */
+#    else
+#      include <conio.h>        /* for getche() console input */
+#    endif
+#  endif /* ?__EMX__ */
+#  define FGETS(buf,len,stream)  dos_kbd_gets(buf,len)
+#else
+#  include <unistd.h>           /* for isatty() prototype */
+#  define FGETS fgets
+#endif
+
+/* #define DEBUG  :  this enables the Trace() macros */
+
+/* #define FORBID_LATIN1_CTRL  :  this requires the user to re-enter any
+   text that includes control characters discouraged by the PNG spec; text
+   that includes an escape character (27) must be re-entered regardless */
+
+#include "writepng.h"   /* typedefs, common macros, writepng prototypes */
+
+
+
+/* local prototypes */
+
+static int  wpng_isvalid_latin1(uch *p, int len);
+static void wpng_cleanup(void);
+
+#ifdef DOS_OS2_W32
+   static char *dos_kbd_gets(char *buf, int len);
+#endif
+
+
+
+static mainprog_info wpng_info;   /* lone global */
+
+
+
+int main(int argc, char **argv)
+{
+#ifndef DOS_OS2_W32
+    FILE *keybd;
+#endif
+#ifdef sgi
+    FILE *tmpfile;      /* or we could just use keybd, since no overlap */
+    char tmpline[80];
+#endif
+    char *inname = NULL, outname[256];
+    char *p, pnmchar, pnmline[256];
+    char *bgstr, *textbuf = NULL;
+    ulg rowbytes;
+    int rc, len = 0;
+    int error = 0;
+    int text = FALSE;
+    int maxval;
+    double LUT_exponent;                /* just the lookup table */
+    double CRT_exponent = 2.2;          /* just the monitor */
+    double default_display_exponent;    /* whole display system */
+    double default_gamma = 0.0;
+
+
+    wpng_info.infile = NULL;
+    wpng_info.outfile = NULL;
+    wpng_info.image_data = NULL;
+    wpng_info.row_pointers = NULL;
+    wpng_info.filter = FALSE;
+    wpng_info.interlaced = FALSE;
+    wpng_info.have_bg = FALSE;
+    wpng_info.have_time = FALSE;
+    wpng_info.have_text = 0;
+    wpng_info.gamma = 0.0;
+
+
+    /* First get the default value for our display-system exponent, i.e.,
+     * the product of the CRT exponent and the exponent corresponding to
+     * the frame-buffer's lookup table (LUT), if any.  If the PNM image
+     * looks correct on the user's display system, its file gamma is the
+     * inverse of this value.  (Note that this is not an exhaustive list
+     * of LUT values--e.g., OpenStep has a lot of weird ones--but it should
+     * cover 99% of the current possibilities.  This section must ensure
+     * that default_display_exponent is positive.) */
+
+#if defined(NeXT)
+    /* third-party utilities can modify the default LUT exponent */
+    LUT_exponent = 1.0 / 2.2;
+    /*
+    if (some_next_function_that_returns_gamma(&next_gamma))
+        LUT_exponent = 1.0 / next_gamma;
+     */
+#elif defined(sgi)
+    LUT_exponent = 1.0 / 1.7;
+    /* there doesn't seem to be any documented function to
+     * get the "gamma" value, so we do it the hard way */
+    tmpfile = fopen("/etc/config/system.glGammaVal", "r");
+    if (tmpfile) {
+        double sgi_gamma;
+
+        fgets(tmpline, 80, tmpfile);
+        fclose(tmpfile);
+        sgi_gamma = atof(tmpline);
+        if (sgi_gamma > 0.0)
+            LUT_exponent = 1.0 / sgi_gamma;
+    }
+#elif defined(Macintosh)
+    LUT_exponent = 1.8 / 2.61;
+    /*
+    if (some_mac_function_that_returns_gamma(&mac_gamma))
+        LUT_exponent = mac_gamma / 2.61;
+     */
+#else
+    LUT_exponent = 1.0;   /* assume no LUT:  most PCs */
+#endif
+
+    /* the defaults above give 1.0, 1.3, 1.5 and 2.2, respectively: */
+    default_display_exponent = LUT_exponent * CRT_exponent;
+
+
+    /* If the user has set the SCREEN_GAMMA environment variable as suggested
+     * (somewhat imprecisely) in the libpng documentation, use that; otherwise
+     * use the default value we just calculated.  Either way, the user may
+     * override this via a command-line option. */
+
+    if ((p = getenv("SCREEN_GAMMA")) != NULL) {
+        double exponent = atof(p);
+
+        if (exponent > 0.0)
+            default_gamma = 1.0 / exponent;
+    }
+
+    if (default_gamma == 0.0)
+        default_gamma = 1.0 / default_display_exponent;
+
+
+    /* Now parse the command line for options and the PNM filename. */
+
+    while (*++argv && !error) {
+        if (!strncmp(*argv, "-i", 2)) {
+            wpng_info.interlaced = TRUE;
+        } else if (!strncmp(*argv, "-time", 3)) {
+            wpng_info.modtime = time(NULL);
+            wpng_info.have_time = TRUE;
+        } else if (!strncmp(*argv, "-text", 3)) {
+            text = TRUE;
+        } else if (!strncmp(*argv, "-gamma", 2)) {
+            if (!*++argv)
+                ++error;
+            else {
+                wpng_info.gamma = atof(*argv);
+                if (wpng_info.gamma <= 0.0)
+                    ++error;
+                else if (wpng_info.gamma > 1.01)
+                    fprintf(stderr, PROGNAME
+                      " warning:  file gammas are usually less than 1.0\n");
+            }
+        } else if (!strncmp(*argv, "-bgcolor", 4)) {
+            if (!*++argv)
+                ++error;
+            else {
+                bgstr = *argv;
+                if (strlen(bgstr) != 7 || bgstr[0] != '#')
+                    ++error;
+                else {
+                    unsigned r, g, b;  /* this way quiets compiler warnings */
+
+                    sscanf(bgstr+1, "%2x%2x%2x", &r, &g, &b);
+                    wpng_info.bg_red   = (uch)r;
+                    wpng_info.bg_green = (uch)g;
+                    wpng_info.bg_blue  = (uch)b;
+                    wpng_info.have_bg = TRUE;
+                }
+            }
+        } else {
+            if (**argv != '-') {
+                inname = *argv;
+                if (argv[1])   /* shouldn't be any more args after filename */
+                    ++error;
+            } else
+                ++error;   /* not expecting any other options */
+        }
+    }
+
+
+    /* open the input and output files, or register an error and abort */
+
+    if (!inname) {
+        if (isatty(0)) {
+            fprintf(stderr, PROGNAME
+              ":  must give input filename or provide image data via stdin\n");
+            ++error;
+        } else {
+#ifdef DOS_OS2_W32
+            /* some buggy C libraries require BOTH setmode() and fdopen(bin) */
+            setmode(fileno(stdin), O_BINARY);
+            setmode(fileno(stdout), O_BINARY);
+#endif
+            if ((wpng_info.infile = fdopen(fileno(stdin), "rb")) == NULL) {
+                fprintf(stderr, PROGNAME
+                  ":  unable to reopen stdin in binary mode\n");
+                ++error;
+            } else
+            if ((wpng_info.outfile = fdopen(fileno(stdout), "wb")) == NULL) {
+                fprintf(stderr, PROGNAME
+                  ":  unable to reopen stdout in binary mode\n");
+                fclose(wpng_info.infile);
+                ++error;
+            } else
+                wpng_info.filter = TRUE;
+        }
+    } else if ((len = strlen(inname)) > 250) {
+        fprintf(stderr, PROGNAME ":  input filename is too long [%d chars]\n",
+          len);
+        ++error;
+    } else if (!(wpng_info.infile = fopen(inname, "rb"))) {
+        fprintf(stderr, PROGNAME ":  can't open input file [%s]\n", inname);
+        ++error;
+    }
+
+    if (!error) {
+        fgets(pnmline, 256, wpng_info.infile);
+        if (pnmline[0] != 'P' || ((pnmchar = pnmline[1]) != '5' &&
+            pnmchar != '6' && pnmchar != '8'))
+        {
+            fprintf(stderr, PROGNAME
+              ":  input file [%s] is not a binary PGM, PPM or PAM file\n",
+              inname);
+            ++error;
+        } else {
+            wpng_info.pnmtype = (int)(pnmchar - '0');
+            if (wpng_info.pnmtype != 8)
+                wpng_info.have_bg = FALSE;  /* no need for bg if opaque */
+            do {
+                fgets(pnmline, 256, wpng_info.infile);  /* lose any comments */
+            } while (pnmline[0] == '#');
+            sscanf(pnmline, "%ld %ld", &wpng_info.width, &wpng_info.height);
+            do {
+                fgets(pnmline, 256, wpng_info.infile);  /* more comment lines */
+            } while (pnmline[0] == '#');
+            sscanf(pnmline, "%d", &maxval);
+            if (wpng_info.width <= 0L || wpng_info.height <= 0L ||
+                maxval != 255)
+            {
+                fprintf(stderr, PROGNAME
+                  ":  only positive width/height, maxval == 255 allowed \n");
+                ++error;
+            }
+            wpng_info.sample_depth = 8;  /* <==> maxval 255 */
+
+            if (!wpng_info.filter) {
+                /* make outname from inname */
+                if ((p = strrchr(inname, '.')) == NULL ||
+                    (p - inname) != (len - 4))
+                {
+                    strcpy(outname, inname);
+                    strcpy(outname+len, ".png");
+                } else {
+                    len -= 4;
+                    strncpy(outname, inname, len);
+                    strcpy(outname+len, ".png");
+                }
+                /* check if outname already exists; if not, open */
+                if ((wpng_info.outfile = fopen(outname, "rb")) != NULL) {
+                    fprintf(stderr, PROGNAME ":  output file exists [%s]\n",
+                      outname);
+                    fclose(wpng_info.outfile);
+                    ++error;
+                } else if (!(wpng_info.outfile = fopen(outname, "wb"))) {
+                    fprintf(stderr, PROGNAME ":  can't open output file [%s]\n",
+                      outname);
+                    ++error;
+                }
+            }
+        }
+        if (error) {
+            fclose(wpng_info.infile);
+            wpng_info.infile = NULL;
+            if (wpng_info.filter) {
+                fclose(wpng_info.outfile);
+                wpng_info.outfile = NULL;
+            }
+        }
+    }
+
+
+    /* if we had any errors, print usage and die horrible death...arrr! */
+
+    if (error) {
+        fprintf(stderr, "\n%s %s:  %s\n", PROGNAME, VERSION, APPNAME);
+        writepng_version_info();
+        fprintf(stderr, "\n"
+"Usage:  %s [-gamma exp] [-bgcolor bg] [-text] [-time] [-interlace] pnmfile\n"
+"or: ... | %s [-gamma exp] [-bgcolor bg] [-text] [-time] [-interlace] | ...\n"
+         "    exp \ttransfer-function exponent (``gamma'') of the image in\n"
+         "\t\t  floating-point format (e.g., ``%.5f''); if image looks\n"
+         "\t\t  correct on given display system, image gamma is equal to\n"
+         "\t\t  inverse of display-system exponent, i.e., 1 / (LUT * CRT)\n"
+         "\t\t  (where LUT = lookup-table exponent and CRT = CRT exponent;\n"
+         "\t\t  first varies, second is usually 2.2, all are positive)\n"
+         "    bg  \tdesired background color for alpha-channel images, in\n"
+         "\t\t  7-character hex RGB format (e.g., ``#ff7700'' for orange:\n"
+         "\t\t  same as HTML colors)\n"
+         "    -text\tprompt interactively for text info (tEXt chunks)\n"
+         "    -time\tinclude a tIME chunk (last modification time)\n"
+         "    -interlace\twrite interlaced PNG image\n"
+         "\n"
+"pnmfile or stdin must be a binary PGM (`P5'), PPM (`P6') or (extremely\n"
+"unofficial and unsupported!) PAM (`P8') file.  Currently it is required\n"
+"to have maxval == 255 (i.e., no scaling).  If pnmfile is specified, it\n"
+"is converted to the corresponding PNG file with the same base name but a\n"
+"``.png'' extension; files read from stdin are converted and sent to stdout.\n"
+"The conversion is progressive (low memory usage) unless interlacing is\n"
+"requested; in that case the whole image will be buffered in memory and\n"
+"written in one call.\n"
+         "\n", PROGNAME, PROGNAME, default_gamma);
+        exit(1);
+    }
+
+
+    /* prepare the text buffers for libpng's use; note that even though
+     * PNG's png_text struct includes a length field, we don't have to fill
+     * it out */
+
+    if (text &&
+#ifndef DOS_OS2_W32
+        (keybd = fdopen(fileno(stderr), "r")) != NULL &&
+#endif
+        (textbuf = (char *)malloc((5 + 9)*75)) != NULL)
+    {
+        int i, valid, result;
+
+        fprintf(stderr,
+          "Enter text info (no more than 72 characters per line);\n");
+        fprintf(stderr, "to skip a field, hit the <Enter> key.\n");
+        /* note:  just <Enter> leaves len == 1 */
+
+        do {
+            valid = TRUE;
+            p = textbuf + TEXT_TITLE_OFFSET;
+            fprintf(stderr, "  Title: ");
+            fflush(stderr);
+            if (FGETS(p, 74, keybd) && (len = strlen(p)) > 1) {
+                if (p[len-1] == '\n')
+                    p[--len] = '\0';
+                wpng_info.title = p;
+                wpng_info.have_text |= TEXT_TITLE;
+                if ((result = wpng_isvalid_latin1((uch *)p, len)) >= 0) {
+                    fprintf(stderr, "    " PROGNAME " warning:  character code"
+                      " %u is %sdiscouraged by the PNG\n    specification "
+                      "[first occurrence was at character position #%d]\n",
+                      (unsigned)p[result], (p[result] == 27)? "strongly " : "",
+                      result+1);
+                    fflush(stderr);
+#ifdef FORBID_LATIN1_CTRL
+                    wpng_info.have_text &= ~TEXT_TITLE;
+                    valid = FALSE;
+#else
+                    if (p[result] == 27) {    /* escape character */
+                        wpng_info.have_text &= ~TEXT_TITLE;
+                        valid = FALSE;
+                    }
+#endif
+                }
+            }
+        } while (!valid);
+
+        do {
+            valid = TRUE;
+            p = textbuf + TEXT_AUTHOR_OFFSET;
+            fprintf(stderr, "  Author: ");
+            fflush(stderr);
+            if (FGETS(p, 74, keybd) && (len = strlen(p)) > 1) {
+                if (p[len-1] == '\n')
+                    p[--len] = '\0';
+                wpng_info.author = p;
+                wpng_info.have_text |= TEXT_AUTHOR;
+                if ((result = wpng_isvalid_latin1((uch *)p, len)) >= 0) {
+                    fprintf(stderr, "    " PROGNAME " warning:  character code"
+                      " %u is %sdiscouraged by the PNG\n    specification "
+                      "[first occurrence was at character position #%d]\n",
+                      (unsigned)p[result], (p[result] == 27)? "strongly " : "",
+                      result+1);
+                    fflush(stderr);
+#ifdef FORBID_LATIN1_CTRL
+                    wpng_info.have_text &= ~TEXT_AUTHOR;
+                    valid = FALSE;
+#else
+                    if (p[result] == 27) {    /* escape character */
+                        wpng_info.have_text &= ~TEXT_AUTHOR;
+                        valid = FALSE;
+                    }
+#endif
+                }
+            }
+        } while (!valid);
+
+        do {
+            valid = TRUE;
+            p = textbuf + TEXT_DESC_OFFSET;
+            fprintf(stderr, "  Description (up to 9 lines):\n");
+            for (i = 1;  i < 10;  ++i) {
+                fprintf(stderr, "    [%d] ", i);
+                fflush(stderr);
+                if (FGETS(p, 74, keybd) && (len = strlen(p)) > 1)
+                    p += len;   /* now points at NULL; char before is newline */
+                else
+                    break;
+            }
+            if ((len = p - (textbuf + TEXT_DESC_OFFSET)) > 1) {
+                if (p[-1] == '\n') {
+                    p[-1] = '\0';
+                    --len;
+                }
+                wpng_info.desc = textbuf + TEXT_DESC_OFFSET;
+                wpng_info.have_text |= TEXT_DESC;
+                p = textbuf + TEXT_DESC_OFFSET;
+                if ((result = wpng_isvalid_latin1((uch *)p, len)) >= 0) {
+                    fprintf(stderr, "    " PROGNAME " warning:  character code"
+                      " %u is %sdiscouraged by the PNG\n    specification "
+                      "[first occurrence was at character position #%d]\n",
+                      (unsigned)p[result], (p[result] == 27)? "strongly " : "",
+                      result+1);
+                    fflush(stderr);
+#ifdef FORBID_LATIN1_CTRL
+                    wpng_info.have_text &= ~TEXT_DESC;
+                    valid = FALSE;
+#else
+                    if (p[result] == 27) {    /* escape character */
+                        wpng_info.have_text &= ~TEXT_DESC;
+                        valid = FALSE;
+                    }
+#endif
+                }
+            }
+        } while (!valid);
+
+        do {
+            valid = TRUE;
+            p = textbuf + TEXT_COPY_OFFSET;
+            fprintf(stderr, "  Copyright: ");
+            fflush(stderr);
+            if (FGETS(p, 74, keybd) && (len = strlen(p)) > 1) {
+                if (p[len-1] == '\n')
+                    p[--len] = '\0';
+                wpng_info.copyright = p;
+                wpng_info.have_text |= TEXT_COPY;
+                if ((result = wpng_isvalid_latin1((uch *)p, len)) >= 0) {
+                    fprintf(stderr, "    " PROGNAME " warning:  character code"
+                      " %u is %sdiscouraged by the PNG\n    specification "
+                      "[first occurrence was at character position #%d]\n",
+                      (unsigned)p[result], (p[result] == 27)? "strongly " : "",
+                      result+1);
+                    fflush(stderr);
+#ifdef FORBID_LATIN1_CTRL
+                    wpng_info.have_text &= ~TEXT_COPY;
+                    valid = FALSE;
+#else
+                    if (p[result] == 27) {    /* escape character */
+                        wpng_info.have_text &= ~TEXT_COPY;
+                        valid = FALSE;
+                    }
+#endif
+                }
+            }
+        } while (!valid);
+
+        do {
+            valid = TRUE;
+            p = textbuf + TEXT_EMAIL_OFFSET;
+            fprintf(stderr, "  E-mail: ");
+            fflush(stderr);
+            if (FGETS(p, 74, keybd) && (len = strlen(p)) > 1) {
+                if (p[len-1] == '\n')
+                    p[--len] = '\0';
+                wpng_info.email = p;
+                wpng_info.have_text |= TEXT_EMAIL;
+                if ((result = wpng_isvalid_latin1((uch *)p, len)) >= 0) {
+                    fprintf(stderr, "    " PROGNAME " warning:  character code"
+                      " %u is %sdiscouraged by the PNG\n    specification "
+                      "[first occurrence was at character position #%d]\n",
+                      (unsigned)p[result], (p[result] == 27)? "strongly " : "",
+                      result+1);
+                    fflush(stderr);
+#ifdef FORBID_LATIN1_CTRL
+                    wpng_info.have_text &= ~TEXT_EMAIL;
+                    valid = FALSE;
+#else
+                    if (p[result] == 27) {    /* escape character */
+                        wpng_info.have_text &= ~TEXT_EMAIL;
+                        valid = FALSE;
+                    }
+#endif
+                }
+            }
+        } while (!valid);
+
+        do {
+            valid = TRUE;
+            p = textbuf + TEXT_URL_OFFSET;
+            fprintf(stderr, "  URL: ");
+            fflush(stderr);
+            if (FGETS(p, 74, keybd) && (len = strlen(p)) > 1) {
+                if (p[len-1] == '\n')
+                    p[--len] = '\0';
+                wpng_info.url = p;
+                wpng_info.have_text |= TEXT_URL;
+                if ((result = wpng_isvalid_latin1((uch *)p, len)) >= 0) {
+                    fprintf(stderr, "    " PROGNAME " warning:  character code"
+                      " %u is %sdiscouraged by the PNG\n    specification "
+                      "[first occurrence was at character position #%d]\n",
+                      (unsigned)p[result], (p[result] == 27)? "strongly " : "",
+                      result+1);
+                    fflush(stderr);
+#ifdef FORBID_LATIN1_CTRL
+                    wpng_info.have_text &= ~TEXT_URL;
+                    valid = FALSE;
+#else
+                    if (p[result] == 27) {    /* escape character */
+                        wpng_info.have_text &= ~TEXT_URL;
+                        valid = FALSE;
+                    }
+#endif
+                }
+            }
+        } while (!valid);
+
+#ifndef DOS_OS2_W32
+        fclose(keybd);
+#endif
+
+    } else if (text) {
+        fprintf(stderr, PROGNAME ":  unable to allocate memory for text\n");
+        text = FALSE;
+        wpng_info.have_text = 0;
+    }
+
+
+    /* allocate libpng stuff, initialize transformations, write pre-IDAT data */
+
+    if ((rc = writepng_init(&wpng_info)) != 0) {
+        switch (rc) {
+            case 2:
+                fprintf(stderr, PROGNAME
+                  ":  libpng initialization problem (longjmp)\n");
+                break;
+            case 4:
+                fprintf(stderr, PROGNAME ":  insufficient memory\n");
+                break;
+            case 11:
+                fprintf(stderr, PROGNAME
+                  ":  internal logic error (unexpected PNM type)\n");
+                break;
+            default:
+                fprintf(stderr, PROGNAME
+                  ":  unknown writepng_init() error\n");
+                break;
+        }
+        exit(rc);
+    }
+
+
+    /* free textbuf, since it's a completely local variable and all text info
+     * has just been written to the PNG file */
+
+    if (text && textbuf) {
+        free(textbuf);
+        textbuf = NULL;
+    }
+
+
+    /* calculate rowbytes on basis of image type; note that this becomes much
+     * more complicated if we choose to support PBM type, ASCII PNM types, or
+     * 16-bit-per-sample binary data [currently not an official NetPBM type] */
+
+    if (wpng_info.pnmtype == 5)
+        rowbytes = wpng_info.width;
+    else if (wpng_info.pnmtype == 6)
+        rowbytes = wpng_info.width * 3;
+    else /* if (wpng_info.pnmtype == 8) */
+        rowbytes = wpng_info.width * 4;
+
+
+    /* read and write the image, either in its entirety (if writing interlaced
+     * PNG) or row by row (if non-interlaced) */
+
+    fprintf(stderr, "Encoding image data...\n");
+    fflush(stderr);
+
+    if (wpng_info.interlaced) {
+        long i;
+        ulg bytes;
+        ulg image_bytes = rowbytes * wpng_info.height;   /* overflow? */
+
+        wpng_info.image_data = (uch *)malloc(image_bytes);
+        wpng_info.row_pointers = (uch **)malloc(wpng_info.height*sizeof(uch *));
+        if (wpng_info.image_data == NULL || wpng_info.row_pointers == NULL) {
+            fprintf(stderr, PROGNAME ":  insufficient memory for image data\n");
+            writepng_cleanup(&wpng_info);
+            wpng_cleanup();
+            exit(5);
+        }
+        for (i = 0;  i < wpng_info.height;  ++i)
+            wpng_info.row_pointers[i] = wpng_info.image_data + i*rowbytes;
+        bytes = fread(wpng_info.image_data, 1, image_bytes, wpng_info.infile);
+        if (bytes != image_bytes) {
+            fprintf(stderr, PROGNAME ":  expected %lu bytes, got %lu bytes\n",
+              image_bytes, bytes);
+            fprintf(stderr, "  (continuing anyway)\n");
+        }
+        if (writepng_encode_image(&wpng_info) != 0) {
+            fprintf(stderr, PROGNAME
+              ":  libpng problem (longjmp) while writing image data\n");
+            writepng_cleanup(&wpng_info);
+            wpng_cleanup();
+            exit(2);
+        }
+
+    } else /* not interlaced:  write progressively (row by row) */ {
+        long j;
+        ulg bytes;
+
+        wpng_info.image_data = (uch *)malloc(rowbytes);
+        if (wpng_info.image_data == NULL) {
+            fprintf(stderr, PROGNAME ":  insufficient memory for row data\n");
+            writepng_cleanup(&wpng_info);
+            wpng_cleanup();
+            exit(5);
+        }
+        error = 0;
+        for (j = wpng_info.height;  j > 0L;  --j) {
+            bytes = fread(wpng_info.image_data, 1, rowbytes, wpng_info.infile);
+            if (bytes != rowbytes) {
+                fprintf(stderr, PROGNAME
+                  ":  expected %lu bytes, got %lu bytes (row %ld)\n", rowbytes,
+                  bytes, wpng_info.height-j);
+                ++error;
+                break;
+            }
+            if (writepng_encode_row(&wpng_info) != 0) {
+                fprintf(stderr, PROGNAME
+                  ":  libpng problem (longjmp) while writing row %ld\n",
+                  wpng_info.height-j);
+                ++error;
+                break;
+            }
+        }
+        if (error) {
+            writepng_cleanup(&wpng_info);
+            wpng_cleanup();
+            exit(2);
+        }
+        if (writepng_encode_finish(&wpng_info) != 0) {
+            fprintf(stderr, PROGNAME ":  error on final libpng call\n");
+            writepng_cleanup(&wpng_info);
+            wpng_cleanup();
+            exit(2);
+        }
+    }
+
+
+    /* OK, we're done (successfully):  clean up all resources and quit */
+
+    fprintf(stderr, "Done.\n");
+    fflush(stderr);
+
+    writepng_cleanup(&wpng_info);
+    wpng_cleanup();
+
+    return 0;
+}
+
+
+
+
+
+static int wpng_isvalid_latin1(uch *p, int len)
+{
+    int i, result = -1;
+
+    for (i = 0;  i < len;  ++i) {
+        if (p[i] == 10 || (p[i] > 31 && p[i] < 127) || p[i] > 160)
+            continue;           /* character is completely OK */
+        if (result < 0 || (p[result] != 27 && p[i] == 27))
+            result = i;         /* mark location of first questionable one */
+    }                           /*  or of first escape character (bad) */
+
+    return result;
+}
+
+
+
+
+
+static void wpng_cleanup(void)
+{
+    if (wpng_info.outfile) {
+        fclose(wpng_info.outfile);
+        wpng_info.outfile = NULL;
+    }
+
+    if (wpng_info.infile) {
+        fclose(wpng_info.infile);
+        wpng_info.infile = NULL;
+    }
+
+    if (wpng_info.image_data) {
+        free(wpng_info.image_data);
+        wpng_info.image_data = NULL;
+    }
+
+    if (wpng_info.row_pointers) {
+        free(wpng_info.row_pointers);
+        wpng_info.row_pointers = NULL;
+    }
+}
+
+
+
+
+#ifdef DOS_OS2_W32
+
+static char *dos_kbd_gets(char *buf, int len)
+{
+    int ch, count=0;
+
+    do {
+        buf[count++] = ch = getche();
+    } while (ch != '\r' && count < len-1);
+
+    buf[count--] = '\0';        /* terminate string */
+    if (buf[count] == '\r')     /* Enter key makes CR, so change to newline */
+        buf[count] = '\n';
+
+    fprintf(stderr, "\n");      /* Enter key does *not* cause a newline */
+    fflush(stderr);
+
+    return buf;
+}
+
+#endif /* DOS_OS2_W32 */
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/writepng.c b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/writepng.c
index 8373c16..f07f4a8 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/writepng.c
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/writepng.c
@@ -1,400 +1,400 @@
-/*---------------------------------------------------------------------------

-

-   wpng - simple PNG-writing program                             writepng.c

-

-  ---------------------------------------------------------------------------

-

-      Copyright (c) 1998-2007 Greg Roelofs.  All rights reserved.

-

-      This software is provided "as is," without warranty of any kind,

-      express or implied.  In no event shall the author or contributors

-      be held liable for any damages arising in any way from the use of

-      this software.

-

-      The contents of this file are DUAL-LICENSED.  You may modify and/or

-      redistribute this software according to the terms of one of the

-      following two licenses (at your option):

-

-

-      LICENSE 1 ("BSD-like with advertising clause"):

-

-      Permission is granted to anyone to use this software for any purpose,

-      including commercial applications, and to alter it and redistribute

-      it freely, subject to the following restrictions:

-

-      1. Redistributions of source code must retain the above copyright

-         notice, disclaimer, and this list of conditions.

-      2. Redistributions in binary form must reproduce the above copyright

-         notice, disclaimer, and this list of conditions in the documenta-

-         tion and/or other materials provided with the distribution.

-      3. All advertising materials mentioning features or use of this

-         software must display the following acknowledgment:

-

-            This product includes software developed by Greg Roelofs

-            and contributors for the book, "PNG: The Definitive Guide,"

-            published by O'Reilly and Associates.

-

-

-      LICENSE 2 (GNU GPL v2 or later):

-

-      This program is free software; you can redistribute it and/or modify

-      it under the terms of the GNU General Public License as published by

-      the Free Software Foundation; either version 2 of the License, or

-      (at your option) any later version.

-

-      This program is distributed in the hope that it will be useful,

-      but WITHOUT ANY WARRANTY; without even the implied warranty of

-      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

-      GNU General Public License for more details.

-

-      You should have received a copy of the GNU General Public License

-      along with this program; if not, write to the Free Software Foundation,

-      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

-

-  ---------------------------------------------------------------------------*/

-

-

-#include <stdlib.h>     /* for exit() prototype */

-

-#include "png.h"        /* libpng header; includes zlib.h and setjmp.h */

-#include "writepng.h"   /* typedefs, common macros, public prototypes */

-

-

-/* local prototype */

-

-static void writepng_error_handler(png_structp png_ptr, png_const_charp msg);

-

-

-

-void writepng_version_info(void)

-{

-  fprintf(stderr, "   Compiled with libpng %s; using libpng %s.\n",

-    PNG_LIBPNG_VER_STRING, png_libpng_ver);

-  fprintf(stderr, "   Compiled with zlib %s; using zlib %s.\n",

-    ZLIB_VERSION, zlib_version);

-}

-

-

-

-

-/* returns 0 for success, 2 for libpng problem, 4 for out of memory, 11 for

- *  unexpected pnmtype; note that outfile might be stdout */

-

-int writepng_init(mainprog_info *mainprog_ptr)

-{

-    png_structp  png_ptr;       /* note:  temporary variables! */

-    png_infop  info_ptr;

-    int color_type, interlace_type;

-

-

-    /* could also replace libpng warning-handler (final NULL), but no need: */

-

-    png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, mainprog_ptr,

-      writepng_error_handler, NULL);

-    if (!png_ptr)

-        return 4;   /* out of memory */

-

-    info_ptr = png_create_info_struct(png_ptr);

-    if (!info_ptr) {

-        png_destroy_write_struct(&png_ptr, NULL);

-        return 4;   /* out of memory */

-    }

-

-

-    /* setjmp() must be called in every function that calls a PNG-writing

-     * libpng function, unless an alternate error handler was installed--

-     * but compatible error handlers must either use longjmp() themselves

-     * (as in this program) or some other method to return control to

-     * application code, so here we go: */

-

-    if (setjmp(mainprog_ptr->jmpbuf)) {

-        png_destroy_write_struct(&png_ptr, &info_ptr);

-        return 2;

-    }

-

-

-    /* make sure outfile is (re)opened in BINARY mode */

-

-    png_init_io(png_ptr, mainprog_ptr->outfile);

-

-

-    /* set the compression levels--in general, always want to leave filtering

-     * turned on (except for palette images) and allow all of the filters,

-     * which is the default; want 32K zlib window, unless entire image buffer

-     * is 16K or smaller (unknown here)--also the default; usually want max

-     * compression (NOT the default); and remaining compression flags should

-     * be left alone */

-

-    png_set_compression_level(png_ptr, Z_BEST_COMPRESSION);

-/*

-    >> this is default for no filtering; Z_FILTERED is default otherwise:

-    png_set_compression_strategy(png_ptr, Z_DEFAULT_STRATEGY);

-    >> these are all defaults:

-    png_set_compression_mem_level(png_ptr, 8);

-    png_set_compression_window_bits(png_ptr, 15);

-    png_set_compression_method(png_ptr, 8);

- */

-

-

-    /* set the image parameters appropriately */

-

-    if (mainprog_ptr->pnmtype == 5)

-        color_type = PNG_COLOR_TYPE_GRAY;

-    else if (mainprog_ptr->pnmtype == 6)

-        color_type = PNG_COLOR_TYPE_RGB;

-    else if (mainprog_ptr->pnmtype == 8)

-        color_type = PNG_COLOR_TYPE_RGB_ALPHA;

-    else {

-        png_destroy_write_struct(&png_ptr, &info_ptr);

-        return 11;

-    }

-

-    interlace_type = mainprog_ptr->interlaced? PNG_INTERLACE_ADAM7 :

-                                               PNG_INTERLACE_NONE;

-

-    png_set_IHDR(png_ptr, info_ptr, mainprog_ptr->width, mainprog_ptr->height,

-      mainprog_ptr->sample_depth, color_type, interlace_type,

-      PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);

-

-    if (mainprog_ptr->gamma > 0.0)

-        png_set_gAMA(png_ptr, info_ptr, mainprog_ptr->gamma);

-

-    if (mainprog_ptr->have_bg) {   /* we know it's RGBA, not gray+alpha */

-        png_color_16  background;

-

-        background.red = mainprog_ptr->bg_red;

-        background.green = mainprog_ptr->bg_green;

-        background.blue = mainprog_ptr->bg_blue;

-        png_set_bKGD(png_ptr, info_ptr, &background);

-    }

-

-    if (mainprog_ptr->have_time) {

-        png_time  modtime;

-

-        png_convert_from_time_t(&modtime, mainprog_ptr->modtime);

-        png_set_tIME(png_ptr, info_ptr, &modtime);

-    }

-

-    if (mainprog_ptr->have_text) {

-        png_text  text[6];

-        int  num_text = 0;

-

-        if (mainprog_ptr->have_text & TEXT_TITLE) {

-            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;

-            text[num_text].key = "Title";

-            text[num_text].text = mainprog_ptr->title;

-            ++num_text;

-        }

-        if (mainprog_ptr->have_text & TEXT_AUTHOR) {

-            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;

-            text[num_text].key = "Author";

-            text[num_text].text = mainprog_ptr->author;

-            ++num_text;

-        }

-        if (mainprog_ptr->have_text & TEXT_DESC) {

-            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;

-            text[num_text].key = "Description";

-            text[num_text].text = mainprog_ptr->desc;

-            ++num_text;

-        }

-        if (mainprog_ptr->have_text & TEXT_COPY) {

-            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;

-            text[num_text].key = "Copyright";

-            text[num_text].text = mainprog_ptr->copyright;

-            ++num_text;

-        }

-        if (mainprog_ptr->have_text & TEXT_EMAIL) {

-            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;

-            text[num_text].key = "E-mail";

-            text[num_text].text = mainprog_ptr->email;

-            ++num_text;

-        }

-        if (mainprog_ptr->have_text & TEXT_URL) {

-            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;

-            text[num_text].key = "URL";

-            text[num_text].text = mainprog_ptr->url;

-            ++num_text;

-        }

-        png_set_text(png_ptr, info_ptr, text, num_text);

-    }

-

-

-    /* write all chunks up to (but not including) first IDAT */

-

-    png_write_info(png_ptr, info_ptr);

-

-

-    /* if we wanted to write any more text info *after* the image data, we

-     * would set up text struct(s) here and call png_set_text() again, with

-     * just the new data; png_set_tIME() could also go here, but it would

-     * have no effect since we already called it above (only one tIME chunk

-     * allowed) */

-

-

-    /* set up the transformations:  for now, just pack low-bit-depth pixels

-     * into bytes (one, two or four pixels per byte) */

-

-    png_set_packing(png_ptr);

-/*  png_set_shift(png_ptr, &sig_bit);  to scale low-bit-depth values */

-

-

-    /* make sure we save our pointers for use in writepng_encode_image() */

-

-    mainprog_ptr->png_ptr = png_ptr;

-    mainprog_ptr->info_ptr = info_ptr;

-

-

-    /* OK, that's all we need to do for now; return happy */

-

-    return 0;

-}

-

-

-

-

-

-/* returns 0 for success, 2 for libpng (longjmp) problem */

-

-int writepng_encode_image(mainprog_info *mainprog_ptr)

-{

-    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;

-    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;

-

-

-    /* as always, setjmp() must be called in every function that calls a

-     * PNG-writing libpng function */

-

-    if (setjmp(mainprog_ptr->jmpbuf)) {

-        png_destroy_write_struct(&png_ptr, &info_ptr);

-        mainprog_ptr->png_ptr = NULL;

-        mainprog_ptr->info_ptr = NULL;

-        return 2;

-    }

-

-

-    /* and now we just write the whole image; libpng takes care of interlacing

-     * for us */

-

-    png_write_image(png_ptr, mainprog_ptr->row_pointers);

-

-

-    /* since that's it, we also close out the end of the PNG file now--if we

-     * had any text or time info to write after the IDATs, second argument

-     * would be info_ptr, but we optimize slightly by sending NULL pointer: */

-

-    png_write_end(png_ptr, NULL);

-

-    return 0;

-}

-

-

-

-

-

-/* returns 0 if succeeds, 2 if libpng problem */

-

-int writepng_encode_row(mainprog_info *mainprog_ptr)  /* NON-interlaced only! */

-{

-    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;

-    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;

-

-

-    /* as always, setjmp() must be called in every function that calls a

-     * PNG-writing libpng function */

-

-    if (setjmp(mainprog_ptr->jmpbuf)) {

-        png_destroy_write_struct(&png_ptr, &info_ptr);

-        mainprog_ptr->png_ptr = NULL;

-        mainprog_ptr->info_ptr = NULL;

-        return 2;

-    }

-

-

-    /* image_data points at our one row of image data */

-

-    png_write_row(png_ptr, mainprog_ptr->image_data);

-

-    return 0;

-}

-

-

-

-

-

-/* returns 0 if succeeds, 2 if libpng problem */

-

-int writepng_encode_finish(mainprog_info *mainprog_ptr)   /* NON-interlaced! */

-{

-    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;

-    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;

-

-

-    /* as always, setjmp() must be called in every function that calls a

-     * PNG-writing libpng function */

-

-    if (setjmp(mainprog_ptr->jmpbuf)) {

-        png_destroy_write_struct(&png_ptr, &info_ptr);

-        mainprog_ptr->png_ptr = NULL;

-        mainprog_ptr->info_ptr = NULL;

-        return 2;

-    }

-

-

-    /* close out PNG file; if we had any text or time info to write after

-     * the IDATs, second argument would be info_ptr: */

-

-    png_write_end(png_ptr, NULL);

-

-    return 0;

-}

-

-

-

-

-

-void writepng_cleanup(mainprog_info *mainprog_ptr)

-{

-    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;

-    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;

-

-    if (png_ptr && info_ptr)

-        png_destroy_write_struct(&png_ptr, &info_ptr);

-}

-

-

-

-

-

-static void writepng_error_handler(png_structp png_ptr, png_const_charp msg)

-{

-    mainprog_info  *mainprog_ptr;

-

-    /* This function, aside from the extra step of retrieving the "error

-     * pointer" (below) and the fact that it exists within the application

-     * rather than within libpng, is essentially identical to libpng's

-     * default error handler.  The second point is critical:  since both

-     * setjmp() and longjmp() are called from the same code, they are

-     * guaranteed to have compatible notions of how big a jmp_buf is,

-     * regardless of whether _BSD_SOURCE or anything else has (or has not)

-     * been defined. */

-

-    fprintf(stderr, "writepng libpng error: %s\n", msg);

-    fflush(stderr);

-

-    mainprog_ptr = png_get_error_ptr(png_ptr);

-    if (mainprog_ptr == NULL) {         /* we are completely hosed now */

-        fprintf(stderr,

-          "writepng severe error:  jmpbuf not recoverable; terminating.\n");

-        fflush(stderr);

-        exit(99);

-    }

-

-    /* Now we have our data structure we can use the information in it

-     * to return control to our own higher level code (all the points

-     * where 'setjmp' is called in this file.)  This will work with other

-     * error handling mechanisms as well - libpng always calls png_error

-     * when it can proceed no further, thus, so long as the error handler

-     * is intercepted, application code can do its own error recovery.

-     */

-    longjmp(mainprog_ptr->jmpbuf, 1);

-}

+/*---------------------------------------------------------------------------
+
+   wpng - simple PNG-writing program                             writepng.c
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-2007 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      The contents of this file are DUAL-LICENSED.  You may modify and/or
+      redistribute this software according to the terms of one of the
+      following two licenses (at your option):
+
+
+      LICENSE 1 ("BSD-like with advertising clause"):
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+
+      LICENSE 2 (GNU GPL v2 or later):
+
+      This program is free software; you can redistribute it and/or modify
+      it under the terms of the GNU General Public License as published by
+      the Free Software Foundation; either version 2 of the License, or
+      (at your option) any later version.
+
+      This program is distributed in the hope that it will be useful,
+      but WITHOUT ANY WARRANTY; without even the implied warranty of
+      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+      GNU General Public License for more details.
+
+      You should have received a copy of the GNU General Public License
+      along with this program; if not, write to the Free Software Foundation,
+      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+  ---------------------------------------------------------------------------*/
+
+
+#include <stdlib.h>     /* for exit() prototype */
+
+#include "png.h"        /* libpng header; includes zlib.h and setjmp.h */
+#include "writepng.h"   /* typedefs, common macros, public prototypes */
+
+
+/* local prototype */
+
+static void writepng_error_handler(png_structp png_ptr, png_const_charp msg);
+
+
+
+void writepng_version_info(void)
+{
+  fprintf(stderr, "   Compiled with libpng %s; using libpng %s.\n",
+    PNG_LIBPNG_VER_STRING, png_libpng_ver);
+  fprintf(stderr, "   Compiled with zlib %s; using zlib %s.\n",
+    ZLIB_VERSION, zlib_version);
+}
+
+
+
+
+/* returns 0 for success, 2 for libpng problem, 4 for out of memory, 11 for
+ *  unexpected pnmtype; note that outfile might be stdout */
+
+int writepng_init(mainprog_info *mainprog_ptr)
+{
+    png_structp  png_ptr;       /* note:  temporary variables! */
+    png_infop  info_ptr;
+    int color_type, interlace_type;
+
+
+    /* could also replace libpng warning-handler (final NULL), but no need: */
+
+    png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, mainprog_ptr,
+      writepng_error_handler, NULL);
+    if (!png_ptr)
+        return 4;   /* out of memory */
+
+    info_ptr = png_create_info_struct(png_ptr);
+    if (!info_ptr) {
+        png_destroy_write_struct(&png_ptr, NULL);
+        return 4;   /* out of memory */
+    }
+
+
+    /* setjmp() must be called in every function that calls a PNG-writing
+     * libpng function, unless an alternate error handler was installed--
+     * but compatible error handlers must either use longjmp() themselves
+     * (as in this program) or some other method to return control to
+     * application code, so here we go: */
+
+    if (setjmp(mainprog_ptr->jmpbuf)) {
+        png_destroy_write_struct(&png_ptr, &info_ptr);
+        return 2;
+    }
+
+
+    /* make sure outfile is (re)opened in BINARY mode */
+
+    png_init_io(png_ptr, mainprog_ptr->outfile);
+
+
+    /* set the compression levels--in general, always want to leave filtering
+     * turned on (except for palette images) and allow all of the filters,
+     * which is the default; want 32K zlib window, unless entire image buffer
+     * is 16K or smaller (unknown here)--also the default; usually want max
+     * compression (NOT the default); and remaining compression flags should
+     * be left alone */
+
+    png_set_compression_level(png_ptr, Z_BEST_COMPRESSION);
+/*
+    >> this is default for no filtering; Z_FILTERED is default otherwise:
+    png_set_compression_strategy(png_ptr, Z_DEFAULT_STRATEGY);
+    >> these are all defaults:
+    png_set_compression_mem_level(png_ptr, 8);
+    png_set_compression_window_bits(png_ptr, 15);
+    png_set_compression_method(png_ptr, 8);
+ */
+
+
+    /* set the image parameters appropriately */
+
+    if (mainprog_ptr->pnmtype == 5)
+        color_type = PNG_COLOR_TYPE_GRAY;
+    else if (mainprog_ptr->pnmtype == 6)
+        color_type = PNG_COLOR_TYPE_RGB;
+    else if (mainprog_ptr->pnmtype == 8)
+        color_type = PNG_COLOR_TYPE_RGB_ALPHA;
+    else {
+        png_destroy_write_struct(&png_ptr, &info_ptr);
+        return 11;
+    }
+
+    interlace_type = mainprog_ptr->interlaced? PNG_INTERLACE_ADAM7 :
+                                               PNG_INTERLACE_NONE;
+
+    png_set_IHDR(png_ptr, info_ptr, mainprog_ptr->width, mainprog_ptr->height,
+      mainprog_ptr->sample_depth, color_type, interlace_type,
+      PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);
+
+    if (mainprog_ptr->gamma > 0.0)
+        png_set_gAMA(png_ptr, info_ptr, mainprog_ptr->gamma);
+
+    if (mainprog_ptr->have_bg) {   /* we know it's RGBA, not gray+alpha */
+        png_color_16  background;
+
+        background.red = mainprog_ptr->bg_red;
+        background.green = mainprog_ptr->bg_green;
+        background.blue = mainprog_ptr->bg_blue;
+        png_set_bKGD(png_ptr, info_ptr, &background);
+    }
+
+    if (mainprog_ptr->have_time) {
+        png_time  modtime;
+
+        png_convert_from_time_t(&modtime, mainprog_ptr->modtime);
+        png_set_tIME(png_ptr, info_ptr, &modtime);
+    }
+
+    if (mainprog_ptr->have_text) {
+        png_text  text[6];
+        int  num_text = 0;
+
+        if (mainprog_ptr->have_text & TEXT_TITLE) {
+            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;
+            text[num_text].key = "Title";
+            text[num_text].text = mainprog_ptr->title;
+            ++num_text;
+        }
+        if (mainprog_ptr->have_text & TEXT_AUTHOR) {
+            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;
+            text[num_text].key = "Author";
+            text[num_text].text = mainprog_ptr->author;
+            ++num_text;
+        }
+        if (mainprog_ptr->have_text & TEXT_DESC) {
+            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;
+            text[num_text].key = "Description";
+            text[num_text].text = mainprog_ptr->desc;
+            ++num_text;
+        }
+        if (mainprog_ptr->have_text & TEXT_COPY) {
+            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;
+            text[num_text].key = "Copyright";
+            text[num_text].text = mainprog_ptr->copyright;
+            ++num_text;
+        }
+        if (mainprog_ptr->have_text & TEXT_EMAIL) {
+            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;
+            text[num_text].key = "E-mail";
+            text[num_text].text = mainprog_ptr->email;
+            ++num_text;
+        }
+        if (mainprog_ptr->have_text & TEXT_URL) {
+            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;
+            text[num_text].key = "URL";
+            text[num_text].text = mainprog_ptr->url;
+            ++num_text;
+        }
+        png_set_text(png_ptr, info_ptr, text, num_text);
+    }
+
+
+    /* write all chunks up to (but not including) first IDAT */
+
+    png_write_info(png_ptr, info_ptr);
+
+
+    /* if we wanted to write any more text info *after* the image data, we
+     * would set up text struct(s) here and call png_set_text() again, with
+     * just the new data; png_set_tIME() could also go here, but it would
+     * have no effect since we already called it above (only one tIME chunk
+     * allowed) */
+
+
+    /* set up the transformations:  for now, just pack low-bit-depth pixels
+     * into bytes (one, two or four pixels per byte) */
+
+    png_set_packing(png_ptr);
+/*  png_set_shift(png_ptr, &sig_bit);  to scale low-bit-depth values */
+
+
+    /* make sure we save our pointers for use in writepng_encode_image() */
+
+    mainprog_ptr->png_ptr = png_ptr;
+    mainprog_ptr->info_ptr = info_ptr;
+
+
+    /* OK, that's all we need to do for now; return happy */
+
+    return 0;
+}
+
+
+
+
+
+/* returns 0 for success, 2 for libpng (longjmp) problem */
+
+int writepng_encode_image(mainprog_info *mainprog_ptr)
+{
+    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;
+    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;
+
+
+    /* as always, setjmp() must be called in every function that calls a
+     * PNG-writing libpng function */
+
+    if (setjmp(mainprog_ptr->jmpbuf)) {
+        png_destroy_write_struct(&png_ptr, &info_ptr);
+        mainprog_ptr->png_ptr = NULL;
+        mainprog_ptr->info_ptr = NULL;
+        return 2;
+    }
+
+
+    /* and now we just write the whole image; libpng takes care of interlacing
+     * for us */
+
+    png_write_image(png_ptr, mainprog_ptr->row_pointers);
+
+
+    /* since that's it, we also close out the end of the PNG file now--if we
+     * had any text or time info to write after the IDATs, second argument
+     * would be info_ptr, but we optimize slightly by sending NULL pointer: */
+
+    png_write_end(png_ptr, NULL);
+
+    return 0;
+}
+
+
+
+
+
+/* returns 0 if succeeds, 2 if libpng problem */
+
+int writepng_encode_row(mainprog_info *mainprog_ptr)  /* NON-interlaced only! */
+{
+    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;
+    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;
+
+
+    /* as always, setjmp() must be called in every function that calls a
+     * PNG-writing libpng function */
+
+    if (setjmp(mainprog_ptr->jmpbuf)) {
+        png_destroy_write_struct(&png_ptr, &info_ptr);
+        mainprog_ptr->png_ptr = NULL;
+        mainprog_ptr->info_ptr = NULL;
+        return 2;
+    }
+
+
+    /* image_data points at our one row of image data */
+
+    png_write_row(png_ptr, mainprog_ptr->image_data);
+
+    return 0;
+}
+
+
+
+
+
+/* returns 0 if succeeds, 2 if libpng problem */
+
+int writepng_encode_finish(mainprog_info *mainprog_ptr)   /* NON-interlaced! */
+{
+    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;
+    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;
+
+
+    /* as always, setjmp() must be called in every function that calls a
+     * PNG-writing libpng function */
+
+    if (setjmp(mainprog_ptr->jmpbuf)) {
+        png_destroy_write_struct(&png_ptr, &info_ptr);
+        mainprog_ptr->png_ptr = NULL;
+        mainprog_ptr->info_ptr = NULL;
+        return 2;
+    }
+
+
+    /* close out PNG file; if we had any text or time info to write after
+     * the IDATs, second argument would be info_ptr: */
+
+    png_write_end(png_ptr, NULL);
+
+    return 0;
+}
+
+
+
+
+
+void writepng_cleanup(mainprog_info *mainprog_ptr)
+{
+    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;
+    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;
+
+    if (png_ptr && info_ptr)
+        png_destroy_write_struct(&png_ptr, &info_ptr);
+}
+
+
+
+
+
+static void writepng_error_handler(png_structp png_ptr, png_const_charp msg)
+{
+    mainprog_info  *mainprog_ptr;
+
+    /* This function, aside from the extra step of retrieving the "error
+     * pointer" (below) and the fact that it exists within the application
+     * rather than within libpng, is essentially identical to libpng's
+     * default error handler.  The second point is critical:  since both
+     * setjmp() and longjmp() are called from the same code, they are
+     * guaranteed to have compatible notions of how big a jmp_buf is,
+     * regardless of whether _BSD_SOURCE or anything else has (or has not)
+     * been defined. */
+
+    fprintf(stderr, "writepng libpng error: %s\n", msg);
+    fflush(stderr);
+
+    mainprog_ptr = png_get_error_ptr(png_ptr);
+    if (mainprog_ptr == NULL) {         /* we are completely hosed now */
+        fprintf(stderr,
+          "writepng severe error:  jmpbuf not recoverable; terminating.\n");
+        fflush(stderr);
+        exit(99);
+    }
+
+    /* Now we have our data structure we can use the information in it
+     * to return control to our own higher level code (all the points
+     * where 'setjmp' is called in this file.)  This will work with other
+     * error handling mechanisms as well - libpng always calls png_error
+     * when it can proceed no further, thus, so long as the error handler
+     * is intercepted, application code can do its own error recovery.
+     */
+    longjmp(mainprog_ptr->jmpbuf, 1);
+}
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/writepng.h b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/writepng.h
index 904e4fb..78b966b 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/writepng.h
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/gregbook/writepng.h
@@ -1,133 +1,133 @@
-/*---------------------------------------------------------------------------

-

-   wpng - simple PNG-writing program                             writepng.h

-

-  ---------------------------------------------------------------------------

-

-      Copyright (c) 1998-2007 Greg Roelofs.  All rights reserved.

-

-      This software is provided "as is," without warranty of any kind,

-      express or implied.  In no event shall the author or contributors

-      be held liable for any damages arising in any way from the use of

-      this software.

-

-      The contents of this file are DUAL-LICENSED.  You may modify and/or

-      redistribute this software according to the terms of one of the

-      following two licenses (at your option):

-

-

-      LICENSE 1 ("BSD-like with advertising clause"):

-

-      Permission is granted to anyone to use this software for any purpose,

-      including commercial applications, and to alter it and redistribute

-      it freely, subject to the following restrictions:

-

-      1. Redistributions of source code must retain the above copyright

-         notice, disclaimer, and this list of conditions.

-      2. Redistributions in binary form must reproduce the above copyright

-         notice, disclaimer, and this list of conditions in the documenta-

-         tion and/or other materials provided with the distribution.

-      3. All advertising materials mentioning features or use of this

-         software must display the following acknowledgment:

-

-            This product includes software developed by Greg Roelofs

-            and contributors for the book, "PNG: The Definitive Guide,"

-            published by O'Reilly and Associates.

-

-

-      LICENSE 2 (GNU GPL v2 or later):

-

-      This program is free software; you can redistribute it and/or modify

-      it under the terms of the GNU General Public License as published by

-      the Free Software Foundation; either version 2 of the License, or

-      (at your option) any later version.

-

-      This program is distributed in the hope that it will be useful,

-      but WITHOUT ANY WARRANTY; without even the implied warranty of

-      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

-      GNU General Public License for more details.

-

-      You should have received a copy of the GNU General Public License

-      along with this program; if not, write to the Free Software Foundation,

-      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

-

-  ---------------------------------------------------------------------------*/

-

-#ifndef TRUE

-#  define TRUE 1

-#  define FALSE 0

-#endif

-

-#ifndef MAX

-#  define MAX(a,b)  ((a) > (b)? (a) : (b))

-#  define MIN(a,b)  ((a) < (b)? (a) : (b))

-#endif

-

-#ifdef DEBUG

-#  define Trace(x)  {fprintf x ; fflush(stderr); fflush(stdout);}

-#else

-#  define Trace(x)  ;

-#endif

-

-#define TEXT_TITLE    0x01

-#define TEXT_AUTHOR   0x02

-#define TEXT_DESC     0x04

-#define TEXT_COPY     0x08

-#define TEXT_EMAIL    0x10

-#define TEXT_URL      0x20

-

-#define TEXT_TITLE_OFFSET        0

-#define TEXT_AUTHOR_OFFSET      72

-#define TEXT_COPY_OFFSET     (2*72)

-#define TEXT_EMAIL_OFFSET    (3*72)

-#define TEXT_URL_OFFSET      (4*72)

-#define TEXT_DESC_OFFSET     (5*72)

-

-typedef unsigned char   uch;

-typedef unsigned short  ush;

-typedef unsigned long   ulg;

-

-typedef struct _mainprog_info {

-    double gamma;

-    long width;

-    long height;

-    time_t modtime;

-    FILE *infile;

-    FILE *outfile;

-    void *png_ptr;

-    void *info_ptr;

-    uch *image_data;

-    uch **row_pointers;

-    char *title;

-    char *author;

-    char *desc;

-    char *copyright;

-    char *email;

-    char *url;

-    int filter;    /* command-line-filter flag, not PNG row filter! */

-    int pnmtype;

-    int sample_depth;

-    int interlaced;

-    int have_bg;

-    int have_time;

-    int have_text;

-    jmp_buf jmpbuf;

-    uch bg_red;

-    uch bg_green;

-    uch bg_blue;

-} mainprog_info;

-

-

-/* prototypes for public functions in writepng.c */

-

-void writepng_version_info(void);

-

-int writepng_init(mainprog_info *mainprog_ptr);

-

-int writepng_encode_image(mainprog_info *mainprog_ptr);

-

-int writepng_encode_row(mainprog_info *mainprog_ptr);

-

-int writepng_encode_finish(mainprog_info *mainprog_ptr);

-

-void writepng_cleanup(mainprog_info *mainprog_ptr);

+/*---------------------------------------------------------------------------
+
+   wpng - simple PNG-writing program                             writepng.h
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-2007 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      The contents of this file are DUAL-LICENSED.  You may modify and/or
+      redistribute this software according to the terms of one of the
+      following two licenses (at your option):
+
+
+      LICENSE 1 ("BSD-like with advertising clause"):
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+
+      LICENSE 2 (GNU GPL v2 or later):
+
+      This program is free software; you can redistribute it and/or modify
+      it under the terms of the GNU General Public License as published by
+      the Free Software Foundation; either version 2 of the License, or
+      (at your option) any later version.
+
+      This program is distributed in the hope that it will be useful,
+      but WITHOUT ANY WARRANTY; without even the implied warranty of
+      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+      GNU General Public License for more details.
+
+      You should have received a copy of the GNU General Public License
+      along with this program; if not, write to the Free Software Foundation,
+      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+  ---------------------------------------------------------------------------*/
+
+#ifndef TRUE
+#  define TRUE 1
+#  define FALSE 0
+#endif
+
+#ifndef MAX
+#  define MAX(a,b)  ((a) > (b)? (a) : (b))
+#  define MIN(a,b)  ((a) < (b)? (a) : (b))
+#endif
+
+#ifdef DEBUG
+#  define Trace(x)  {fprintf x ; fflush(stderr); fflush(stdout);}
+#else
+#  define Trace(x)  ;
+#endif
+
+#define TEXT_TITLE    0x01
+#define TEXT_AUTHOR   0x02
+#define TEXT_DESC     0x04
+#define TEXT_COPY     0x08
+#define TEXT_EMAIL    0x10
+#define TEXT_URL      0x20
+
+#define TEXT_TITLE_OFFSET        0
+#define TEXT_AUTHOR_OFFSET      72
+#define TEXT_COPY_OFFSET     (2*72)
+#define TEXT_EMAIL_OFFSET    (3*72)
+#define TEXT_URL_OFFSET      (4*72)
+#define TEXT_DESC_OFFSET     (5*72)
+
+typedef unsigned char   uch;
+typedef unsigned short  ush;
+typedef unsigned long   ulg;
+
+typedef struct _mainprog_info {
+    double gamma;
+    long width;
+    long height;
+    time_t modtime;
+    FILE *infile;
+    FILE *outfile;
+    void *png_ptr;
+    void *info_ptr;
+    uch *image_data;
+    uch **row_pointers;
+    char *title;
+    char *author;
+    char *desc;
+    char *copyright;
+    char *email;
+    char *url;
+    int filter;    /* command-line-filter flag, not PNG row filter! */
+    int pnmtype;
+    int sample_depth;
+    int interlaced;
+    int have_bg;
+    int have_time;
+    int have_text;
+    jmp_buf jmpbuf;
+    uch bg_red;
+    uch bg_green;
+    uch bg_blue;
+} mainprog_info;
+
+
+/* prototypes for public functions in writepng.c */
+
+void writepng_version_info(void);
+
+int writepng_init(mainprog_info *mainprog_ptr);
+
+int writepng_encode_image(mainprog_info *mainprog_ptr);
+
+int writepng_encode_row(mainprog_info *mainprog_ptr);
+
+int writepng_encode_finish(mainprog_info *mainprog_ptr);
+
+void writepng_cleanup(mainprog_info *mainprog_ptr);
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/libtests/pngvalid.c b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/libtests/pngvalid.c
index c7068fa..3dd6f21 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/libtests/pngvalid.c
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/libtests/pngvalid.c
@@ -1,9837 +1,9837 @@
-

-/* pngvalid.c - validate libpng by constructing then reading png files.

- *

- * Last changed in libpng 1.5.8 [%RDATE%]

- * Copyright (c) 2012 Glenn Randers-Pehrson

- * Written by John Cunningham Bowler

- *

- * This code is released under the libpng license.

- * For conditions of distribution and use, see the disclaimer

- * and license in png.h

- *

- * NOTES:

- *   This is a C program that is intended to be linked against libpng.  It

- *   generates bitmaps internally, stores them as PNG files (using the

- *   sequential write code) then reads them back (using the sequential

- *   read code) and validates that the result has the correct data.

- *

- *   The program can be modified and extended to test the correctness of

- *   transformations performed by libpng.

- */

-

-#define _POSIX_SOURCE 1

-#define _ISOC99_SOURCE 1 /* For floating point */

-#define _GNU_SOURCE 1 /* For the floating point exception extension */

-

-#include <signal.h>

-

-#ifdef HAVE_FEENABLEEXCEPT

-#  include <fenv.h>

-#endif

-

-/* Define the following to use this test against your installed libpng, rather

- * than the one being built here:

- */

-#ifdef PNG_FREESTANDING_TESTS

-#  include <png.h>

-#else

-#  include "../../png.h"

-#endif

-

-#if PNG_LIBPNG_VER < 10500

-/* This deliberately lacks the PNG_CONST. */

-typedef png_byte *png_const_bytep;

-

-/* This is copied from 1.5.1 png.h: */

-#define PNG_INTERLACE_ADAM7_PASSES 7

-#define PNG_PASS_START_ROW(pass) (((1U&~(pass))<<(3-((pass)>>1)))&7)

-#define PNG_PASS_START_COL(pass) (((1U& (pass))<<(3-(((pass)+1)>>1)))&7)

-#define PNG_PASS_ROW_SHIFT(pass) ((pass)>2?(8-(pass))>>1:3)

-#define PNG_PASS_COL_SHIFT(pass) ((pass)>1?(7-(pass))>>1:3)

-#define PNG_PASS_ROWS(height, pass) (((height)+(((1<<PNG_PASS_ROW_SHIFT(pass))\

-   -1)-PNG_PASS_START_ROW(pass)))>>PNG_PASS_ROW_SHIFT(pass))

-#define PNG_PASS_COLS(width, pass) (((width)+(((1<<PNG_PASS_COL_SHIFT(pass))\

-   -1)-PNG_PASS_START_COL(pass)))>>PNG_PASS_COL_SHIFT(pass))

-#define PNG_ROW_FROM_PASS_ROW(yIn, pass) \

-   (((yIn)<<PNG_PASS_ROW_SHIFT(pass))+PNG_PASS_START_ROW(pass))

-#define PNG_COL_FROM_PASS_COL(xIn, pass) \

-   (((xIn)<<PNG_PASS_COL_SHIFT(pass))+PNG_PASS_START_COL(pass))

-#define PNG_PASS_MASK(pass,off) ( \

-   ((0x110145AFU>>(((7-(off))-(pass))<<2)) & 0xFU) | \

-   ((0x01145AF0U>>(((7-(off))-(pass))<<2)) & 0xF0U))

-#define PNG_ROW_IN_INTERLACE_PASS(y, pass) \

-   ((PNG_PASS_MASK(pass,0) >> ((y)&7)) & 1)

-#define PNG_COL_IN_INTERLACE_PASS(x, pass) \

-   ((PNG_PASS_MASK(pass,1) >> ((x)&7)) & 1)

-

-/* These are needed too for the default build: */

-#define PNG_WRITE_16BIT_SUPPORTED

-#define PNG_READ_16BIT_SUPPORTED

-

-/* This comes from pnglibconf.h afer 1.5: */

-#define PNG_FP_1 100000

-#define PNG_GAMMA_THRESHOLD_FIXED\

-   ((png_fixed_point)(PNG_GAMMA_THRESHOLD * PNG_FP_1))

-#endif

-

-#include "zlib.h"   /* For crc32 */

-

-#include <float.h>  /* For floating point constants */

-#include <stdlib.h> /* For malloc */

-#include <string.h> /* For memcpy, memset */

-#include <math.h>   /* For floor */

-

-/* Unused formal parameter errors are removed using the following macro which is

- * expected to have no bad effects on performance.

- */

-#ifndef UNUSED

-#  if defined(__GNUC__) || defined(_MSC_VER)

-#     define UNUSED(param) (void)param;

-#  else

-#     define UNUSED(param)

-#  endif

-#endif

-

-/***************************** EXCEPTION HANDLING *****************************/

-#include "../visupng/cexcept.h"

-

-#ifdef __cplusplus

-#  define this not_the_cpp_this

-#  define new not_the_cpp_new

-#  define voidcast(type, value) static_cast<type>(value)

-#else

-#  define voidcast(type, value) (value)

-#endif /* __cplusplus */

-

-struct png_store;

-define_exception_type(struct png_store*);

-

-/* The following are macros to reduce typing everywhere where the well known

- * name 'the_exception_context' must be defined.

- */

-#define anon_context(ps) struct exception_context *the_exception_context = \

-   &(ps)->exception_context

-#define context(ps,fault) anon_context(ps); png_store *fault

-

-/******************************* UTILITIES ************************************/

-/* Error handling is particularly problematic in production code - error

- * handlers often themselves have bugs which lead to programs that detect

- * minor errors crashing.  The following functions deal with one very

- * common class of errors in error handlers - attempting to format error or

- * warning messages into buffers that are too small.

- */

-static size_t safecat(char *buffer, size_t bufsize, size_t pos,

-   PNG_CONST char *cat)

-{

-   while (pos < bufsize && cat != NULL && *cat != 0)

-      buffer[pos++] = *cat++;

-

-   if (pos >= bufsize)

-      pos = bufsize-1;

-

-   buffer[pos] = 0;

-   return pos;

-}

-

-static size_t safecatn(char *buffer, size_t bufsize, size_t pos, int n)

-{

-   char number[64];

-   sprintf(number, "%d", n);

-   return safecat(buffer, bufsize, pos, number);

-}

-

-#ifdef PNG_READ_TRANSFORMS_SUPPORTED

-static size_t safecatd(char *buffer, size_t bufsize, size_t pos, double d,

-    int precision)

-{

-   char number[64];

-   sprintf(number, "%.*f", precision, d);

-   return safecat(buffer, bufsize, pos, number);

-}

-#endif

-

-static PNG_CONST char invalid[] = "invalid";

-static PNG_CONST char sep[] = ": ";

-

-static PNG_CONST char *colour_types[8] =

-{

-   "grayscale", invalid, "truecolour", "indexed-colour",

-   "grayscale with alpha", invalid, "truecolour with alpha", invalid

-};

-

-/* Convert a double precision value to fixed point. */

-static png_fixed_point

-fix(double d)

-{

-   d = floor(d * PNG_FP_1 + .5);

-   return (png_fixed_point)d;

-}

-

-/* Generate random bytes.  This uses a boring repeatable algorithm and it

- * is implemented here so that it gives the same set of numbers on every

- * architecture.  It's a linear congruential generator (Knuth or Sedgewick

- * "Algorithms") but it comes from the 'feedback taps' table in Horowitz and

- * Hill, "The Art of Electronics".

- */

-static void

-make_random_bytes(png_uint_32* seed, void* pv, size_t size)

-{

-   png_uint_32 u0 = seed[0], u1 = seed[1];

-   png_bytep bytes = voidcast(png_bytep, pv);

-

-   /* There are thirty three bits, the next bit in the sequence is bit-33 XOR

-    * bit-20.  The top 1 bit is in u1, the bottom 32 are in u0.

-    */

-   size_t i;

-   for (i=0; i<size; ++i)

-   {

-      /* First generate 8 new bits then shift them in at the end. */

-      png_uint_32 u = ((u0 >> (20-8)) ^ ((u1 << 7) | (u0 >> (32-7)))) & 0xff;

-      u1 <<= 8;

-      u1 |= u0 >> 24;

-      u0 <<= 8;

-      u0 |= u;

-      *bytes++ = (png_byte)u;

-   }

-

-   seed[0] = u0;

-   seed[1] = u1;

-}

-

-static void

-make_four_random_bytes(png_uint_32* seed, png_bytep bytes)

-{

-   make_random_bytes(seed, bytes, 4);

-}

-

-static void

-randomize(void *pv, size_t size)

-{

-   static png_uint_32 random_seed[2] = {0x56789abc, 0xd};

-   make_random_bytes(random_seed, pv, size);

-}

-

-#define RANDOMIZE(this) randomize(&(this), sizeof (this))

-

-static unsigned int

-random_mod(unsigned int max)

-{

-   unsigned int x;

-

-   RANDOMIZE(x);

-

-   return x % max; /* 0 .. max-1 */

-}

-

-static int

-random_choice(void)

-{

-   unsigned char x;

-

-   RANDOMIZE(x);

-

-   return x & 1;

-}

-

-/* A numeric ID based on PNG file characteristics.  The 'do_interlace' field

- * simply records whether pngvalid did the interlace itself or whether it

- * was done by libpng.  Width and height must be less than 256.  'palette' is an

- * index of the palette to use for formats with a palette (0 otherwise.)

- */

-#define FILEID(col, depth, palette, interlace, width, height, do_interlace) \

-   ((png_uint_32)((col) + ((depth)<<3) + ((palette)<<8) + ((interlace)<<13) + \

-    (((do_interlace)!=0)<<15) + ((width)<<16) + ((height)<<24)))

-

-#define COL_FROM_ID(id) ((png_byte)((id)& 0x7U))

-#define DEPTH_FROM_ID(id) ((png_byte)(((id) >> 3) & 0x1fU))

-#define PALETTE_FROM_ID(id) ((int)(((id) >> 8) & 0x1f))

-#define INTERLACE_FROM_ID(id) ((int)(((id) >> 13) & 0x3))

-#define DO_INTERLACE_FROM_ID(id) ((int)(((id)>>15) & 1))

-#define WIDTH_FROM_ID(id) (((id)>>16) & 0xff)

-#define HEIGHT_FROM_ID(id) (((id)>>24) & 0xff)

-

-/* Utility to construct a standard name for a standard image. */

-static size_t

-standard_name(char *buffer, size_t bufsize, size_t pos, png_byte colour_type,

-    int bit_depth, int npalette, int interlace_type,

-    png_uint_32 w, png_uint_32 h, int do_interlace)

-{

-   pos = safecat(buffer, bufsize, pos, colour_types[colour_type]);

-   if (npalette > 0)

-   {

-      pos = safecat(buffer, bufsize, pos, "[");

-      pos = safecatn(buffer, bufsize, pos, npalette);

-      pos = safecat(buffer, bufsize, pos, "]");

-   }

-   pos = safecat(buffer, bufsize, pos, " ");

-   pos = safecatn(buffer, bufsize, pos, bit_depth);

-   pos = safecat(buffer, bufsize, pos, " bit");

-

-   if (interlace_type != PNG_INTERLACE_NONE)

-   {

-      pos = safecat(buffer, bufsize, pos, " interlaced");

-      if (do_interlace)

-         pos = safecat(buffer, bufsize, pos, "(pngvalid)");

-      else

-         pos = safecat(buffer, bufsize, pos, "(libpng)");

-   }

-

-   if (w > 0 || h > 0)

-   {

-      pos = safecat(buffer, bufsize, pos, " ");

-      pos = safecatn(buffer, bufsize, pos, w);

-      pos = safecat(buffer, bufsize, pos, "x");

-      pos = safecatn(buffer, bufsize, pos, h);

-   }

-

-   return pos;

-}

-

-static size_t

-standard_name_from_id(char *buffer, size_t bufsize, size_t pos, png_uint_32 id)

-{

-   return standard_name(buffer, bufsize, pos, COL_FROM_ID(id),

-      DEPTH_FROM_ID(id), PALETTE_FROM_ID(id), INTERLACE_FROM_ID(id),

-      WIDTH_FROM_ID(id), HEIGHT_FROM_ID(id), DO_INTERLACE_FROM_ID(id));

-}

-

-/* Convenience API and defines to list valid formats.  Note that 16 bit read and

- * write support is required to do 16 bit read tests (we must be able to make a

- * 16 bit image to test!)

- */

-#ifdef PNG_WRITE_16BIT_SUPPORTED

-#  define WRITE_BDHI 4

-#  ifdef PNG_READ_16BIT_SUPPORTED

-#     define READ_BDHI 4

-#     define DO_16BIT

-#  endif

-#else

-#  define WRITE_BDHI 3

-#endif

-#ifndef DO_16BIT

-#  define READ_BDHI 3

-#endif

-

-/* The following defines the number of different palettes to generate for

- * each log bit depth of a colour type 3 standard image.

- */

-#define PALETTE_COUNT(bit_depth) ((bit_depth) > 4 ? 1 : 16)

-

-static int

-next_format(png_bytep colour_type, png_bytep bit_depth, int* palette_number)

-{

-   if (*bit_depth == 0)

-   {

-      *colour_type = 0, *bit_depth = 1, *palette_number = 0;

-      return 1;

-   }

-

-   if (*colour_type == 3)

-   {

-      /* Add multiple palettes for colour type 3. */

-      if (++*palette_number < PALETTE_COUNT(*bit_depth))

-         return 1;

-

-      *palette_number = 0;

-   }

-

-   *bit_depth = (png_byte)(*bit_depth << 1);

-

-   /* Palette images are restricted to 8 bit depth */

-   if (*bit_depth <= 8

-#     ifdef DO_16BIT

-         || (*colour_type != 3 && *bit_depth <= 16)

-#     endif

-      )

-      return 1;

-

-   /* Move to the next color type, or return 0 at the end. */

-   switch (*colour_type)

-   {

-      case 0:

-         *colour_type = 2;

-         *bit_depth = 8;

-         return 1;

-

-      case 2:

-         *colour_type = 3;

-         *bit_depth = 1;

-         return 1;

-

-      case 3:

-         *colour_type = 4;

-         *bit_depth = 8;

-         return 1;

-

-      case 4:

-         *colour_type = 6;

-         *bit_depth = 8;

-         return 1;

-

-      default:

-         return 0;

-   }

-}

-

-#ifdef PNG_READ_TRANSFORMS_SUPPORTED

-static unsigned int

-sample(png_const_bytep row, png_byte colour_type, png_byte bit_depth,

-    png_uint_32 x, unsigned int sample_index)

-{

-   png_uint_32 bit_index, result;

-

-   /* Find a sample index for the desired sample: */

-   x *= bit_depth;

-   bit_index = x;

-

-   if ((colour_type & 1) == 0) /* !palette */

-   {

-      if (colour_type & 2)

-         bit_index *= 3;

-

-      if (colour_type & 4)

-         bit_index += x; /* Alpha channel */

-

-      /* Multiple channels; select one: */

-      if (colour_type & (2+4))

-         bit_index += sample_index * bit_depth;

-   }

-

-   /* Return the sample from the row as an integer. */

-   row += bit_index >> 3;

-   result = *row;

-

-   if (bit_depth == 8)

-      return result;

-

-   else if (bit_depth > 8)

-      return (result << 8) + *++row;

-

-   /* Less than 8 bits per sample. */

-   bit_index &= 7;

-   return (result >> (8-bit_index-bit_depth)) & ((1U<<bit_depth)-1);

-}

-#endif /* PNG_READ_TRANSFORMS_SUPPORTED */

-

-/* Copy a single pixel, of a given size, from one buffer to another -

- * while this is basically bit addressed there is an implicit assumption

- * that pixels 8 or more bits in size are byte aligned and that pixels

- * do not otherwise cross byte boundaries.  (This is, so far as I know,

- * universally true in bitmap computer graphics.  [JCB 20101212])

- *

- * NOTE: The to and from buffers may be the same.

- */

-static void

-pixel_copy(png_bytep toBuffer, png_uint_32 toIndex,

-   png_const_bytep fromBuffer, png_uint_32 fromIndex, unsigned int pixelSize)

-{

-   /* Assume we can multiply by 'size' without overflow because we are

-    * just working in a single buffer.

-    */

-   toIndex *= pixelSize;

-   fromIndex *= pixelSize;

-   if (pixelSize < 8) /* Sub-byte */

-   {

-      /* Mask to select the location of the copied pixel: */

-      unsigned int destMask = ((1U<<pixelSize)-1) << (8-pixelSize-(toIndex&7));

-      /* The following read the entire pixels and clears the extra: */

-      unsigned int destByte = toBuffer[toIndex >> 3] & ~destMask;

-      unsigned int sourceByte = fromBuffer[fromIndex >> 3];

-

-      /* Don't rely on << or >> supporting '0' here, just in case: */

-      fromIndex &= 7;

-      if (fromIndex > 0) sourceByte <<= fromIndex;

-      if ((toIndex & 7) > 0) sourceByte >>= toIndex & 7;

-

-      toBuffer[toIndex >> 3] = (png_byte)(destByte | (sourceByte & destMask));

-   }

-   else /* One or more bytes */

-      memmove(toBuffer+(toIndex>>3), fromBuffer+(fromIndex>>3), pixelSize>>3);

-}

-

-/* Copy a complete row of pixels, taking into account potential partial

- * bytes at the end.

- */

-static void

-row_copy(png_bytep toBuffer, png_const_bytep fromBuffer, unsigned int bitWidth)

-{

-   memcpy(toBuffer, fromBuffer, bitWidth >> 3);

-

-   if ((bitWidth & 7) != 0)

-   {

-      unsigned int mask;

-

-      toBuffer += bitWidth >> 3;

-      fromBuffer += bitWidth >> 3;

-      /* The remaining bits are in the top of the byte, the mask is the bits to

-       * retain.

-       */

-      mask = 0xff >> (bitWidth & 7);

-      *toBuffer = (png_byte)((*toBuffer & mask) | (*fromBuffer & ~mask));

-   }

-}

-

-/* Compare pixels - they are assumed to start at the first byte in the

- * given buffers.

- */

-static int

-pixel_cmp(png_const_bytep pa, png_const_bytep pb, png_uint_32 bit_width)

-{

-#if PNG_LIBPNG_VER < 10506

-   if (memcmp(pa, pb, bit_width>>3) == 0)

-   {

-      png_uint_32 p;

-

-      if ((bit_width & 7) == 0) return 0;

-

-      /* Ok, any differences? */

-      p = pa[bit_width >> 3];

-      p ^= pb[bit_width >> 3];

-

-      if (p == 0) return 0;

-

-      /* There are, but they may not be significant, remove the bits

-       * after the end (the low order bits in PNG.)

-       */

-      bit_width &= 7;

-      p >>= 8-bit_width;

-

-      if (p == 0) return 0;

-   }

-#else

-   /* From libpng-1.5.6 the overwrite should be fixed, so compare the trailing

-    * bits too:

-    */

-   if (memcmp(pa, pb, (bit_width+7)>>3) == 0)

-      return 0;

-#endif

-

-   /* Return the index of the changed byte. */

-   {

-      png_uint_32 where = 0;

-

-      while (pa[where] == pb[where]) ++where;

-      return 1+where;

-   }

-}

-

-/*************************** BASIC PNG FILE WRITING ***************************/

-/* A png_store takes data from the sequential writer or provides data

- * to the sequential reader.  It can also store the result of a PNG

- * write for later retrieval.

- */

-#define STORE_BUFFER_SIZE 500 /* arbitrary */

-typedef struct png_store_buffer

-{

-   struct png_store_buffer*  prev;    /* NOTE: stored in reverse order */

-   png_byte                  buffer[STORE_BUFFER_SIZE];

-} png_store_buffer;

-

-#define FILE_NAME_SIZE 64

-

-typedef struct store_palette_entry /* record of a single palette entry */

-{

-   png_byte red;

-   png_byte green;

-   png_byte blue;

-   png_byte alpha;

-} store_palette_entry, store_palette[256];

-

-typedef struct png_store_file

-{

-   struct png_store_file*  next;      /* as many as you like... */

-   char                    name[FILE_NAME_SIZE];

-   png_uint_32             id;        /* must be correct (see FILEID) */

-   png_size_t              datacount; /* In this (the last) buffer */

-   png_store_buffer        data;      /* Last buffer in file */

-   int                     npalette;  /* Number of entries in palette */

-   store_palette_entry*    palette;   /* May be NULL */

-} png_store_file;

-

-/* The following is a pool of memory allocated by a single libpng read or write

- * operation.

- */

-typedef struct store_pool

-{

-   struct png_store    *store;   /* Back pointer */

-   struct store_memory *list;    /* List of allocated memory */

-   png_byte             mark[4]; /* Before and after data */

-

-   /* Statistics for this run. */

-   png_alloc_size_t     max;     /* Maximum single allocation */

-   png_alloc_size_t     current; /* Current allocation */

-   png_alloc_size_t     limit;   /* Highest current allocation */

-   png_alloc_size_t     total;   /* Total allocation */

-

-   /* Overall statistics (retained across successive runs). */

-   png_alloc_size_t     max_max;

-   png_alloc_size_t     max_limit;

-   png_alloc_size_t     max_total;

-} store_pool;

-

-typedef struct png_store

-{

-   /* For cexcept.h exception handling - simply store one of these;

-    * the context is a self pointer but it may point to a different

-    * png_store (in fact it never does in this program.)

-    */

-   struct exception_context

-                      exception_context;

-

-   unsigned int       verbose :1;

-   unsigned int       treat_warnings_as_errors :1;

-   unsigned int       expect_error :1;

-   unsigned int       expect_warning :1;

-   unsigned int       saw_warning :1;

-   unsigned int       speed :1;

-   unsigned int       progressive :1; /* use progressive read */

-   unsigned int       validated :1;   /* used as a temporary flag */

-   int                nerrors;

-   int                nwarnings;

-   char               test[128]; /* Name of test */

-   char               error[256];

-

-   /* Read fields */

-   png_structp        pread;    /* Used to read a saved file */

-   png_infop          piread;

-   png_store_file*    current;  /* Set when reading */

-   png_store_buffer*  next;     /* Set when reading */

-   png_size_t         readpos;  /* Position in *next */

-   png_byte*          image;    /* Buffer for reading interlaced images */

-   png_size_t         cb_image; /* Size of this buffer */

-   png_size_t         cb_row;   /* Row size of the image(s) */

-   png_uint_32        image_h;  /* Number of rows in a single image */

-   store_pool         read_memory_pool;

-

-   /* Write fields */

-   png_store_file*    saved;

-   png_structp        pwrite;   /* Used when writing a new file */

-   png_infop          piwrite;

-   png_size_t         writepos; /* Position in .new */

-   char               wname[FILE_NAME_SIZE];

-   png_store_buffer   new;      /* The end of the new PNG file being written. */

-   store_pool         write_memory_pool;

-   store_palette_entry* palette;

-   int                  npalette;

-} png_store;

-

-/* Initialization and cleanup */

-static void

-store_pool_mark(png_bytep mark)

-{

-   static png_uint_32 store_seed[2] = { 0x12345678, 1};

-

-   make_four_random_bytes(store_seed, mark);

-}

-

-/* Use this for random 32 bit values; this function makes sure the result is

- * non-zero.

- */

-static png_uint_32

-random_32(void)

-{

-

-   for(;;)

-   {

-      png_byte mark[4];

-      png_uint_32 result;

-

-      store_pool_mark(mark);

-      result = png_get_uint_32(mark);

-

-      if (result != 0)

-         return result;

-   }

-}

-

-static void

-store_pool_init(png_store *ps, store_pool *pool)

-{

-   memset(pool, 0, sizeof *pool);

-

-   pool->store = ps;

-   pool->list = NULL;

-   pool->max = pool->current = pool->limit = pool->total = 0;

-   pool->max_max = pool->max_limit = pool->max_total = 0;

-   store_pool_mark(pool->mark);

-}

-

-static void

-store_init(png_store* ps)

-{

-   memset(ps, 0, sizeof *ps);

-   init_exception_context(&ps->exception_context);

-   store_pool_init(ps, &ps->read_memory_pool);

-   store_pool_init(ps, &ps->write_memory_pool);

-   ps->verbose = 0;

-   ps->treat_warnings_as_errors = 0;

-   ps->expect_error = 0;

-   ps->expect_warning = 0;

-   ps->saw_warning = 0;

-   ps->speed = 0;

-   ps->progressive = 0;

-   ps->validated = 0;

-   ps->nerrors = ps->nwarnings = 0;

-   ps->pread = NULL;

-   ps->piread = NULL;

-   ps->saved = ps->current = NULL;

-   ps->next = NULL;

-   ps->readpos = 0;

-   ps->image = NULL;

-   ps->cb_image = 0;

-   ps->cb_row = 0;

-   ps->image_h = 0;

-   ps->pwrite = NULL;

-   ps->piwrite = NULL;

-   ps->writepos = 0;

-   ps->new.prev = NULL;

-   ps->palette = NULL;

-   ps->npalette = 0;

-}

-

-static void

-store_freebuffer(png_store_buffer* psb)

-{

-   if (psb->prev)

-   {

-      store_freebuffer(psb->prev);

-      free(psb->prev);

-      psb->prev = NULL;

-   }

-}

-

-static void

-store_freenew(png_store *ps)

-{

-   store_freebuffer(&ps->new);

-   ps->writepos = 0;

-   if (ps->palette != NULL)

-   {

-      free(ps->palette);

-      ps->palette = NULL;

-      ps->npalette = 0;

-   }

-}

-

-static void

-store_storenew(png_store *ps)

-{

-   png_store_buffer *pb;

-

-   if (ps->writepos != STORE_BUFFER_SIZE)

-      png_error(ps->pwrite, "invalid store call");

-

-   pb = voidcast(png_store_buffer*, malloc(sizeof *pb));

-

-   if (pb == NULL)

-      png_error(ps->pwrite, "store new: OOM");

-

-   *pb = ps->new;

-   ps->new.prev = pb;

-   ps->writepos = 0;

-}

-

-static void

-store_freefile(png_store_file **ppf)

-{

-   if (*ppf != NULL)

-   {

-      store_freefile(&(*ppf)->next);

-

-      store_freebuffer(&(*ppf)->data);

-      (*ppf)->datacount = 0;

-      if ((*ppf)->palette != NULL)

-      {

-         free((*ppf)->palette);

-         (*ppf)->palette = NULL;

-         (*ppf)->npalette = 0;

-      }

-      free(*ppf);

-      *ppf = NULL;

-   }

-}

-

-/* Main interface to file storeage, after writing a new PNG file (see the API

- * below) call store_storefile to store the result with the given name and id.

- */

-static void

-store_storefile(png_store *ps, png_uint_32 id)

-{

-   png_store_file *pf = voidcast(png_store_file*, malloc(sizeof *pf));

-   if (pf == NULL)

-      png_error(ps->pwrite, "storefile: OOM");

-   safecat(pf->name, sizeof pf->name, 0, ps->wname);

-   pf->id = id;

-   pf->data = ps->new;

-   pf->datacount = ps->writepos;

-   ps->new.prev = NULL;

-   ps->writepos = 0;

-   pf->palette = ps->palette;

-   pf->npalette = ps->npalette;

-   ps->palette = 0;

-   ps->npalette = 0;

-

-   /* And save it. */

-   pf->next = ps->saved;

-   ps->saved = pf;

-}

-

-/* Generate an error message (in the given buffer) */

-static size_t

-store_message(png_store *ps, png_structp pp, char *buffer, size_t bufsize,

-   size_t pos, PNG_CONST char *msg)

-{

-   if (pp != NULL && pp == ps->pread)

-   {

-      /* Reading a file */

-      pos = safecat(buffer, bufsize, pos, "read: ");

-

-      if (ps->current != NULL)

-      {

-         pos = safecat(buffer, bufsize, pos, ps->current->name);

-         pos = safecat(buffer, bufsize, pos, sep);

-      }

-   }

-

-   else if (pp != NULL && pp == ps->pwrite)

-   {

-      /* Writing a file */

-      pos = safecat(buffer, bufsize, pos, "write: ");

-      pos = safecat(buffer, bufsize, pos, ps->wname);

-      pos = safecat(buffer, bufsize, pos, sep);

-   }

-

-   else

-   {

-      /* Neither reading nor writing (or a memory error in struct delete) */

-      pos = safecat(buffer, bufsize, pos, "pngvalid: ");

-   }

-

-   if (ps->test[0] != 0)

-   {

-      pos = safecat(buffer, bufsize, pos, ps->test);

-      pos = safecat(buffer, bufsize, pos, sep);

-   }

-   pos = safecat(buffer, bufsize, pos, msg);

-   return pos;

-}

-

-/* Verbose output to the error stream: */

-static void

-store_verbose(png_store *ps, png_structp pp, png_const_charp prefix,

-   png_const_charp message)

-{

-   char buffer[512];

-

-   if (prefix)

-      fputs(prefix, stderr);

-

-   (void)store_message(ps, pp, buffer, sizeof buffer, 0, message);

-   fputs(buffer, stderr);

-   fputc('\n', stderr);

-}

-

-/* Log an error or warning - the relevant count is always incremented. */

-static void

-store_log(png_store* ps, png_structp pp, png_const_charp message, int is_error)

-{

-   /* The warning is copied to the error buffer if there are no errors and it is

-    * the first warning.  The error is copied to the error buffer if it is the

-    * first error (overwriting any prior warnings).

-    */

-   if (is_error ? (ps->nerrors)++ == 0 :

-       (ps->nwarnings)++ == 0 && ps->nerrors == 0)

-      store_message(ps, pp, ps->error, sizeof ps->error, 0, message);

-

-   if (ps->verbose)

-      store_verbose(ps, pp, is_error ? "error: " : "warning: ", message);

-}

-

-/* Internal error function, called with a png_store but no libpng stuff. */

-static void

-internal_error(png_store *ps, png_const_charp message)

-{

-   store_log(ps, NULL, message, 1 /* error */);

-

-   /* And finally throw an exception. */

-   {

-      struct exception_context *the_exception_context = &ps->exception_context;

-      Throw ps;

-   }

-}

-

-/* Functions to use as PNG callbacks. */

-static void

-store_error(png_structp pp, png_const_charp message) /* PNG_NORETURN */

-{

-   png_store *ps = voidcast(png_store*, png_get_error_ptr(pp));

-

-   if (!ps->expect_error)

-      store_log(ps, pp, message, 1 /* error */);

-

-   /* And finally throw an exception. */

-   {

-      struct exception_context *the_exception_context = &ps->exception_context;

-      Throw ps;

-   }

-}

-

-static void

-store_warning(png_structp pp, png_const_charp message)

-{

-   png_store *ps = voidcast(png_store*, png_get_error_ptr(pp));

-

-   if (!ps->expect_warning)

-      store_log(ps, pp, message, 0 /* warning */);

-   else

-      ps->saw_warning = 1;

-}

-

-/* These somewhat odd functions are used when reading an image to ensure that

- * the buffer is big enough, the png_structp is for errors.

- */

-/* Return a single row from the correct image. */

-static png_bytep

-store_image_row(PNG_CONST png_store* ps, png_structp pp, int nImage,

-   png_uint_32 y)

-{

-   png_size_t coffset = (nImage * ps->image_h + y) * (ps->cb_row + 5) + 2;

-

-   if (ps->image == NULL)

-      png_error(pp, "no allocated image");

-

-   if (coffset + ps->cb_row + 3 > ps->cb_image)

-      png_error(pp, "image too small");

-

-   return ps->image + coffset;

-}

-

-static void

-store_image_free(png_store *ps, png_structp pp)

-{

-   if (ps->image != NULL)

-   {

-      png_bytep image = ps->image;

-

-      if (image[-1] != 0xed || image[ps->cb_image] != 0xfe)

-      {

-         if (pp != NULL)

-            png_error(pp, "png_store image overwrite (1)");

-         else

-            store_log(ps, NULL, "png_store image overwrite (2)", 1);

-      }

-

-      ps->image = NULL;

-      ps->cb_image = 0;

-      --image;

-      free(image);

-   }

-}

-

-static void

-store_ensure_image(png_store *ps, png_structp pp, int nImages, png_size_t cbRow,

-   png_uint_32 cRows)

-{

-   png_size_t cb = nImages * cRows * (cbRow + 5);

-

-   if (ps->cb_image < cb)

-   {

-      png_bytep image;

-

-      store_image_free(ps, pp);

-

-      /* The buffer is deliberately mis-aligned. */

-      image = voidcast(png_bytep, malloc(cb+2));

-      if (image == NULL)

-      {

-         /* Called from the startup - ignore the error for the moment. */

-         if (pp == NULL)

-            return;

-

-         png_error(pp, "OOM allocating image buffer");

-      }

-

-      /* These magic tags are used to detect overwrites above. */

-      ++image;

-      image[-1] = 0xed;

-      image[cb] = 0xfe;

-

-      ps->image = image;

-      ps->cb_image = cb;

-   }

-

-   /* We have an adequate sized image; lay out the rows.  There are 2 bytes at

-    * the start and three at the end of each (this ensures that the row

-    * alignment starts out odd - 2+1 and changes for larger images on each row.)

-    */

-   ps->cb_row = cbRow;

-   ps->image_h = cRows;

-

-   /* For error checking, the whole buffer is set to 10110010 (0xb2 - 178).

-    * This deliberately doesn't match the bits in the size test image which are

-    * outside the image; these are set to 0xff (all 1).  To make the row

-    * comparison work in the 'size' test case the size rows are pre-initialized

-    * to the same value prior to calling 'standard_row'.

-    */

-   memset(ps->image, 178, cb);

-

-   /* Then put in the marks. */

-   while (--nImages >= 0)

-   {

-      png_uint_32 y;

-

-      for (y=0; y<cRows; ++y)

-      {

-         png_bytep row = store_image_row(ps, pp, nImages, y);

-

-         /* The markers: */

-         row[-2] = 190;

-         row[-1] = 239;

-         row[cbRow] = 222;

-         row[cbRow+1] = 173;

-         row[cbRow+2] = 17;

-      }

-   }

-}

-

-static void

-store_image_check(PNG_CONST png_store* ps, png_structp pp, int iImage)

-{

-   png_const_bytep image = ps->image;

-

-   if (image[-1] != 0xed || image[ps->cb_image] != 0xfe)

-      png_error(pp, "image overwrite");

-   else

-   {

-      png_size_t cbRow = ps->cb_row;

-      png_uint_32 rows = ps->image_h;

-

-      image += iImage * (cbRow+5) * ps->image_h;

-

-      image += 2; /* skip image first row markers */

-

-      while (rows-- > 0)

-      {

-         if (image[-2] != 190 || image[-1] != 239)

-            png_error(pp, "row start overwritten");

-

-         if (image[cbRow] != 222 || image[cbRow+1] != 173 ||

-            image[cbRow+2] != 17)

-            png_error(pp, "row end overwritten");

-

-         image += cbRow+5;

-      }

-   }

-}

-

-static void

-store_write(png_structp pp, png_bytep pb, png_size_t st)

-{

-   png_store *ps = voidcast(png_store*, png_get_io_ptr(pp));

-

-   if (ps->pwrite != pp)

-      png_error(pp, "store state damaged");

-

-   while (st > 0)

-   {

-      size_t cb;

-

-      if (ps->writepos >= STORE_BUFFER_SIZE)

-         store_storenew(ps);

-

-      cb = st;

-

-      if (cb > STORE_BUFFER_SIZE - ps->writepos)

-         cb = STORE_BUFFER_SIZE - ps->writepos;

-

-      memcpy(ps->new.buffer + ps->writepos, pb, cb);

-      pb += cb;

-      st -= cb;

-      ps->writepos += cb;

-   }

-}

-

-static void

-store_flush(png_structp pp)

-{

-   UNUSED(pp) /*DOES NOTHING*/

-}

-

-static size_t

-store_read_buffer_size(png_store *ps)

-{

-   /* Return the bytes available for read in the current buffer. */

-   if (ps->next != &ps->current->data)

-      return STORE_BUFFER_SIZE;

-

-   return ps->current->datacount;

-}

-

-#ifdef PNG_READ_TRANSFORMS_SUPPORTED

-/* Return total bytes available for read. */

-static size_t

-store_read_buffer_avail(png_store *ps)

-{

-   if (ps->current != NULL && ps->next != NULL)

-   {

-      png_store_buffer *next = &ps->current->data;

-      size_t cbAvail = ps->current->datacount;

-

-      while (next != ps->next && next != NULL)

-      {

-         next = next->prev;

-         cbAvail += STORE_BUFFER_SIZE;

-      }

-

-      if (next != ps->next)

-         png_error(ps->pread, "buffer read error");

-

-      if (cbAvail > ps->readpos)

-         return cbAvail - ps->readpos;

-   }

-

-   return 0;

-}

-#endif

-

-static int

-store_read_buffer_next(png_store *ps)

-{

-   png_store_buffer *pbOld = ps->next;

-   png_store_buffer *pbNew = &ps->current->data;

-   if (pbOld != pbNew)

-   {

-      while (pbNew != NULL && pbNew->prev != pbOld)

-         pbNew = pbNew->prev;

-

-      if (pbNew != NULL)

-      {

-         ps->next = pbNew;

-         ps->readpos = 0;

-         return 1;

-      }

-

-      png_error(ps->pread, "buffer lost");

-   }

-

-   return 0; /* EOF or error */

-}

-

-/* Need separate implementation and callback to allow use of the same code

- * during progressive read, where the io_ptr is set internally by libpng.

- */

-static void

-store_read_imp(png_store *ps, png_bytep pb, png_size_t st)

-{

-   if (ps->current == NULL || ps->next == NULL)

-      png_error(ps->pread, "store state damaged");

-

-   while (st > 0)

-   {

-      size_t cbAvail = store_read_buffer_size(ps) - ps->readpos;

-

-      if (cbAvail > 0)

-      {

-         if (cbAvail > st) cbAvail = st;

-         memcpy(pb, ps->next->buffer + ps->readpos, cbAvail);

-         st -= cbAvail;

-         pb += cbAvail;

-         ps->readpos += cbAvail;

-      }

-

-      else if (!store_read_buffer_next(ps))

-         png_error(ps->pread, "read beyond end of file");

-   }

-}

-

-static void

-store_read(png_structp pp, png_bytep pb, png_size_t st)

-{

-   png_store *ps = voidcast(png_store*, png_get_io_ptr(pp));

-

-   if (ps == NULL || ps->pread != pp)

-      png_error(pp, "bad store read call");

-

-   store_read_imp(ps, pb, st);

-}

-

-static void

-store_progressive_read(png_store *ps, png_structp pp, png_infop pi)

-{

-   /* Notice that a call to store_read will cause this function to fail because

-    * readpos will be set.

-    */

-   if (ps->pread != pp || ps->current == NULL || ps->next == NULL)

-      png_error(pp, "store state damaged (progressive)");

-

-   do

-   {

-      if (ps->readpos != 0)

-         png_error(pp, "store_read called during progressive read");

-

-      png_process_data(pp, pi, ps->next->buffer, store_read_buffer_size(ps));

-   }

-   while (store_read_buffer_next(ps));

-}

-

-/* The caller must fill this in: */

-static store_palette_entry *

-store_write_palette(png_store *ps, int npalette)

-{

-   if (ps->pwrite == NULL)

-      store_log(ps, NULL, "attempt to write palette without write stream", 1);

-

-   if (ps->palette != NULL)

-      png_error(ps->pwrite, "multiple store_write_palette calls");

-

-   /* This function can only return NULL if called with '0'! */

-   if (npalette > 0)

-   {

-      ps->palette = voidcast(store_palette_entry*, malloc(npalette *

-         sizeof *ps->palette));

-

-      if (ps->palette == NULL)

-         png_error(ps->pwrite, "store new palette: OOM");

-

-      ps->npalette = npalette;

-   }

-

-   return ps->palette;

-}

-

-static store_palette_entry *

-store_current_palette(png_store *ps, int *npalette)

-{

-   /* This is an internal error (the call has been made outside a read

-    * operation.)

-    */

-   if (ps->current == NULL)

-      store_log(ps, ps->pread, "no current stream for palette", 1);

-

-   /* The result may be null if there is no palette. */

-   *npalette = ps->current->npalette;

-   return ps->current->palette;

-}

-

-/***************************** MEMORY MANAGEMENT*** ***************************/

-/* A store_memory is simply the header for an allocated block of memory.  The

- * pointer returned to libpng is just after the end of the header block, the

- * allocated memory is followed by a second copy of the 'mark'.

- */

-typedef struct store_memory

-{

-   store_pool          *pool;    /* Originating pool */

-   struct store_memory *next;    /* Singly linked list */

-   png_alloc_size_t     size;    /* Size of memory allocated */

-   png_byte             mark[4]; /* ID marker */

-} store_memory;

-

-/* Handle a fatal error in memory allocation.  This calls png_error if the

- * libpng struct is non-NULL, else it outputs a message and returns.  This means

- * that a memory problem while libpng is running will abort (png_error) the

- * handling of particular file while one in cleanup (after the destroy of the

- * struct has returned) will simply keep going and free (or attempt to free)

- * all the memory.

- */

-static void

-store_pool_error(png_store *ps, png_structp pp, PNG_CONST char *msg)

-{

-   if (pp != NULL)

-      png_error(pp, msg);

-

-   /* Else we have to do it ourselves.  png_error eventually calls store_log,

-    * above.  store_log accepts a NULL png_structp - it just changes what gets

-    * output by store_message.

-    */

-   store_log(ps, pp, msg, 1 /* error */);

-}

-

-static void

-store_memory_free(png_structp pp, store_pool *pool, store_memory *memory)

-{

-   /* Note that pp may be NULL (see store_pool_delete below), the caller has

-    * found 'memory' in pool->list *and* unlinked this entry, so this is a valid

-    * pointer (for sure), but the contents may have been trashed.

-    */

-   if (memory->pool != pool)

-      store_pool_error(pool->store, pp, "memory corrupted (pool)");

-

-   else if (memcmp(memory->mark, pool->mark, sizeof memory->mark) != 0)

-      store_pool_error(pool->store, pp, "memory corrupted (start)");

-

-   /* It should be safe to read the size field now. */

-   else

-   {

-      png_alloc_size_t cb = memory->size;

-

-      if (cb > pool->max)

-         store_pool_error(pool->store, pp, "memory corrupted (size)");

-

-      else if (memcmp((png_bytep)(memory+1)+cb, pool->mark, sizeof pool->mark)

-         != 0)

-         store_pool_error(pool->store, pp, "memory corrupted (end)");

-

-      /* Finally give the library a chance to find problems too: */

-      else

-         {

-         pool->current -= cb;

-         free(memory);

-         }

-   }

-}

-

-static void

-store_pool_delete(png_store *ps, store_pool *pool)

-{

-   if (pool->list != NULL)

-   {

-      fprintf(stderr, "%s: %s %s: memory lost (list follows):\n", ps->test,

-         pool == &ps->read_memory_pool ? "read" : "write",

-         pool == &ps->read_memory_pool ? (ps->current != NULL ?

-            ps->current->name : "unknown file") : ps->wname);

-      ++ps->nerrors;

-

-      do

-      {

-         store_memory *next = pool->list;

-         pool->list = next->next;

-         next->next = NULL;

-

-         fprintf(stderr, "\t%lu bytes @ %p\n",

-             (unsigned long)next->size, (PNG_CONST void*)(next+1));

-         /* The NULL means this will always return, even if the memory is

-          * corrupted.

-          */

-         store_memory_free(NULL, pool, next);

-      }

-      while (pool->list != NULL);

-   }

-

-   /* And reset the other fields too for the next time. */

-   if (pool->max > pool->max_max) pool->max_max = pool->max;

-   pool->max = 0;

-   if (pool->current != 0) /* unexpected internal error */

-      fprintf(stderr, "%s: %s %s: memory counter mismatch (internal error)\n",

-         ps->test, pool == &ps->read_memory_pool ? "read" : "write",

-         pool == &ps->read_memory_pool ? (ps->current != NULL ?

-            ps->current->name : "unknown file") : ps->wname);

-   pool->current = 0;

-

-   if (pool->limit > pool->max_limit)

-      pool->max_limit = pool->limit;

-

-   pool->limit = 0;

-

-   if (pool->total > pool->max_total)

-      pool->max_total = pool->total;

-

-   pool->total = 0;

-

-   /* Get a new mark too. */

-   store_pool_mark(pool->mark);

-}

-

-/* The memory callbacks: */

-static png_voidp

-store_malloc(png_structp pp, png_alloc_size_t cb)

-{

-   store_pool *pool = voidcast(store_pool*, png_get_mem_ptr(pp));

-   store_memory *new = voidcast(store_memory*, malloc(cb + (sizeof *new) +

-      (sizeof pool->mark)));

-

-   if (new != NULL)

-   {

-      if (cb > pool->max)

-         pool->max = cb;

-

-      pool->current += cb;

-

-      if (pool->current > pool->limit)

-         pool->limit = pool->current;

-

-      pool->total += cb;

-

-      new->size = cb;

-      memcpy(new->mark, pool->mark, sizeof new->mark);

-      memcpy((png_byte*)(new+1) + cb, pool->mark, sizeof pool->mark);

-      new->pool = pool;

-      new->next = pool->list;

-      pool->list = new;

-      ++new;

-   }

-

-   else

-   {

-      /* NOTE: the PNG user malloc function cannot use the png_ptr it is passed

-       * other than to retrieve the allocation pointer!  libpng calls the

-       * store_malloc callback in two basic cases:

-       *

-       * 1) From png_malloc; png_malloc will do a png_error itself if NULL is

-       *    returned.

-       * 2) From png_struct or png_info structure creation; png_malloc is

-       *    to return so cleanup can be performed.

-       *

-       * To handle this store_malloc can log a message, but can't do anything

-       * else.

-       */

-      store_log(pool->store, pp, "out of memory", 1 /* is_error */);

-   }

-

-   return new;

-}

-

-static void

-store_free(png_structp pp, png_voidp memory)

-{

-   store_pool *pool = voidcast(store_pool*, png_get_mem_ptr(pp));

-   store_memory *this = voidcast(store_memory*, memory), **test;

-

-   /* Because libpng calls store_free with a dummy png_struct when deleting

-    * png_struct or png_info via png_destroy_struct_2 it is necessary to check

-    * the passed in png_structp to ensure it is valid, and not pass it to

-    * png_error if it is not.

-    */

-   if (pp != pool->store->pread && pp != pool->store->pwrite)

-      pp = NULL;

-

-   /* First check that this 'memory' really is valid memory - it must be in the

-    * pool list.  If it is, use the shared memory_free function to free it.

-    */

-   --this;

-   for (test = &pool->list; *test != this; test = &(*test)->next)

-   {

-      if (*test == NULL)

-      {

-         store_pool_error(pool->store, pp, "bad pointer to free");

-         return;

-      }

-   }

-

-   /* Unlink this entry, *test == this. */

-   *test = this->next;

-   this->next = NULL;

-   store_memory_free(pp, pool, this);

-}

-

-/* Setup functions. */

-/* Cleanup when aborting a write or after storing the new file. */

-static void

-store_write_reset(png_store *ps)

-{

-   if (ps->pwrite != NULL)

-   {

-      anon_context(ps);

-

-      Try

-         png_destroy_write_struct(&ps->pwrite, &ps->piwrite);

-

-      Catch_anonymous

-      {

-         /* memory corruption: continue. */

-      }

-

-      ps->pwrite = NULL;

-      ps->piwrite = NULL;

-   }

-

-   /* And make sure that all the memory has been freed - this will output

-    * spurious errors in the case of memory corruption above, but this is safe.

-    */

-   store_pool_delete(ps, &ps->write_memory_pool);

-

-   store_freenew(ps);

-}

-

-/* The following is the main write function, it returns a png_struct and,

- * optionally, a png_info suitable for writiing a new PNG file.  Use

- * store_storefile above to record this file after it has been written.  The

- * returned libpng structures as destroyed by store_write_reset above.

- */

-static png_structp

-set_store_for_write(png_store *ps, png_infopp ppi,

-   PNG_CONST char * volatile name)

-{

-   anon_context(ps);

-

-   Try

-   {

-      if (ps->pwrite != NULL)

-         png_error(ps->pwrite, "write store already in use");

-

-      store_write_reset(ps);

-      safecat(ps->wname, sizeof ps->wname, 0, name);

-

-      /* Don't do the slow memory checks if doing a speed test. */

-      if (ps->speed)

-         ps->pwrite = png_create_write_struct(PNG_LIBPNG_VER_STRING,

-            ps, store_error, store_warning);

-

-      else

-         ps->pwrite = png_create_write_struct_2(PNG_LIBPNG_VER_STRING,

-            ps, store_error, store_warning, &ps->write_memory_pool,

-            store_malloc, store_free);

-

-      png_set_write_fn(ps->pwrite, ps, store_write, store_flush);

-

-      if (ppi != NULL)

-         *ppi = ps->piwrite = png_create_info_struct(ps->pwrite);

-   }

-

-   Catch_anonymous

-      return NULL;

-

-   return ps->pwrite;

-}

-

-/* Cleanup when finished reading (either due to error or in the success case).

- */

-static void

-store_read_reset(png_store *ps)

-{

-   if (ps->pread != NULL)

-   {

-      anon_context(ps);

-

-      Try

-         png_destroy_read_struct(&ps->pread, &ps->piread, NULL);

-

-      Catch_anonymous

-      {

-         /* error already output: continue */

-      }

-

-      ps->pread = NULL;

-      ps->piread = NULL;

-   }

-

-   /* Always do this to be safe. */

-   store_pool_delete(ps, &ps->read_memory_pool);

-

-   ps->current = NULL;

-   ps->next = NULL;

-   ps->readpos = 0;

-   ps->validated = 0;

-}

-

-static void

-store_read_set(png_store *ps, png_uint_32 id)

-{

-   png_store_file *pf = ps->saved;

-

-   while (pf != NULL)

-   {

-      if (pf->id == id)

-      {

-         ps->current = pf;

-         ps->next = NULL;

-         store_read_buffer_next(ps);

-         return;

-      }

-

-      pf = pf->next;

-   }

-

-      {

-      size_t pos;

-      char msg[FILE_NAME_SIZE+64];

-

-      pos = standard_name_from_id(msg, sizeof msg, 0, id);

-      pos = safecat(msg, sizeof msg, pos, ": file not found");

-      png_error(ps->pread, msg);

-      }

-}

-

-/* The main interface for reading a saved file - pass the id number of the file

- * to retrieve.  Ids must be unique or the earlier file will be hidden.  The API

- * returns a png_struct and, optionally, a png_info.  Both of these will be

- * destroyed by store_read_reset above.

- */

-static png_structp

-set_store_for_read(png_store *ps, png_infopp ppi, png_uint_32 id,

-   PNG_CONST char *name)

-{

-   /* Set the name for png_error */

-   safecat(ps->test, sizeof ps->test, 0, name);

-

-   if (ps->pread != NULL)

-      png_error(ps->pread, "read store already in use");

-

-   store_read_reset(ps);

-

-   /* Both the create APIs can return NULL if used in their default mode

-    * (because there is no other way of handling an error because the jmp_buf

-    * by default is stored in png_struct and that has not been allocated!)

-    * However, given that store_error works correctly in these circumstances

-    * we don't ever expect NULL in this program.

-    */

-   if (ps->speed)

-      ps->pread = png_create_read_struct(PNG_LIBPNG_VER_STRING, ps,

-          store_error, store_warning);

-

-   else

-      ps->pread = png_create_read_struct_2(PNG_LIBPNG_VER_STRING, ps,

-          store_error, store_warning, &ps->read_memory_pool, store_malloc,

-          store_free);

-

-   if (ps->pread == NULL)

-   {

-      struct exception_context *the_exception_context = &ps->exception_context;

-

-      store_log(ps, NULL, "png_create_read_struct returned NULL (unexpected)",

-         1 /*error*/);

-

-      Throw ps;

-   }

-

-   store_read_set(ps, id);

-

-   if (ppi != NULL)

-      *ppi = ps->piread = png_create_info_struct(ps->pread);

-

-   return ps->pread;

-}

-

-/* The overall cleanup of a store simply calls the above then removes all the

- * saved files.  This does not delete the store itself.

- */

-static void

-store_delete(png_store *ps)

-{

-   store_write_reset(ps);

-   store_read_reset(ps);

-   store_freefile(&ps->saved);

-   store_image_free(ps, NULL);

-}

-

-/*********************** PNG FILE MODIFICATION ON READ ************************/

-/* Files may be modified on read.  The following structure contains a complete

- * png_store together with extra members to handle modification and a special

- * read callback for libpng.  To use this the 'modifications' field must be set

- * to a list of png_modification structures that actually perform the

- * modification, otherwise a png_modifier is functionally equivalent to a

- * png_store.  There is a special read function, set_modifier_for_read, which

- * replaces set_store_for_read.

- */

-typedef enum modifier_state

-{

-   modifier_start,                        /* Initial value */

-   modifier_signature,                    /* Have a signature */

-   modifier_IHDR                          /* Have an IHDR */

-} modifier_state;

-

-typedef struct CIE_color

-{

-   /* A single CIE tristimulus value, representing the unique response of a

-    * standard observer to a variety of light spectra.  The observer recognizes

-    * all spectra that produce this response as the same color, therefore this

-    * is effectively a description of a color.

-    */

-   double X, Y, Z;

-} CIE_color;

-

-static double

-chromaticity_x(CIE_color c)

-{

-   return c.X / (c.X + c.Y + c.Z);

-}

-

-static double

-chromaticity_y(CIE_color c)

-{

-   return c.Y / (c.X + c.Y + c.Z);

-}

-

-typedef struct color_encoding

-{

-   /* A description of an (R,G,B) encoding of color (as defined above); this

-    * includes the actual colors of the (R,G,B) triples (1,0,0), (0,1,0) and

-    * (0,0,1) plus an encoding value that is used to encode the linear

-    * components R, G and B to give the actual values R^gamma, G^gamma and

-    * B^gamma that are stored.

-    */

-   double    gamma;            /* Encoding (file) gamma of space */

-   CIE_color red, green, blue; /* End points */

-} color_encoding;

-

-static CIE_color

-white_point(PNG_CONST color_encoding *encoding)

-{

-   CIE_color white;

-   

-   white.X = encoding->red.X + encoding->green.X + encoding->blue.X;

-   white.Y = encoding->red.Y + encoding->green.Y + encoding->blue.Y;

-   white.Z = encoding->red.Z + encoding->green.Z + encoding->blue.Z;

-

-   return white;

-}

-

-static void

-normalize_color_encoding(color_encoding *encoding)

-{

-   PNG_CONST double whiteY = encoding->red.Y + encoding->green.Y +

-      encoding->blue.Y;

-

-   if (whiteY != 1)

-   {

-      encoding->red.X /= whiteY;

-      encoding->red.Y /= whiteY;

-      encoding->red.Z /= whiteY;

-      encoding->green.X /= whiteY;

-      encoding->green.Y /= whiteY;

-      encoding->green.Z /= whiteY;

-      encoding->blue.X /= whiteY;

-      encoding->blue.Y /= whiteY;

-      encoding->blue.Z /= whiteY;

-   }

-}

-

-static size_t

-safecat_color_encoding(char *buffer, size_t bufsize, size_t pos,

-   PNG_CONST color_encoding *e, double encoding_gamma)

-{

-   if (e != 0)

-   {

-      if (encoding_gamma != 0)

-         pos = safecat(buffer, bufsize, pos, "(");

-      pos = safecat(buffer, bufsize, pos, "R(");

-      pos = safecatd(buffer, bufsize, pos, e->red.X, 4);

-      pos = safecat(buffer, bufsize, pos, ",");

-      pos = safecatd(buffer, bufsize, pos, e->red.Y, 4);

-      pos = safecat(buffer, bufsize, pos, ",");

-      pos = safecatd(buffer, bufsize, pos, e->red.Z, 4);

-      pos = safecat(buffer, bufsize, pos, "),G(");

-      pos = safecatd(buffer, bufsize, pos, e->green.X, 4);

-      pos = safecat(buffer, bufsize, pos, ",");

-      pos = safecatd(buffer, bufsize, pos, e->green.Y, 4);

-      pos = safecat(buffer, bufsize, pos, ",");

-      pos = safecatd(buffer, bufsize, pos, e->green.Z, 4);

-      pos = safecat(buffer, bufsize, pos, "),B(");

-      pos = safecatd(buffer, bufsize, pos, e->blue.X, 4);

-      pos = safecat(buffer, bufsize, pos, ",");

-      pos = safecatd(buffer, bufsize, pos, e->blue.Y, 4);

-      pos = safecat(buffer, bufsize, pos, ",");

-      pos = safecatd(buffer, bufsize, pos, e->blue.Z, 4);

-      pos = safecat(buffer, bufsize, pos, ")");

-      if (encoding_gamma != 0)

-         pos = safecat(buffer, bufsize, pos, ")");

-   }

-

-   if (encoding_gamma != 0)

-   {

-      pos = safecat(buffer, bufsize, pos, "^");

-      pos = safecatd(buffer, bufsize, pos, encoding_gamma, 5);

-   }

-

-   return pos;

-}

-

-typedef struct png_modifier

-{

-   png_store               this;             /* I am a png_store */

-   struct png_modification *modifications;   /* Changes to make */

-

-   modifier_state           state;           /* My state */

-

-   /* Information from IHDR: */

-   png_byte                 bit_depth;       /* From IHDR */

-   png_byte                 colour_type;     /* From IHDR */

-

-   /* While handling PLTE, IDAT and IEND these chunks may be pended to allow

-    * other chunks to be inserted.

-    */

-   png_uint_32              pending_len;

-   png_uint_32              pending_chunk;

-

-   /* Test values */

-   double                   *gammas;

-   unsigned int              ngammas;

-   unsigned int              ngamma_tests;     /* Number of gamma tests to run*/

-   double                    current_gamma;    /* 0 if not set */

-   PNG_CONST color_encoding *encodings;

-   unsigned int              nencodings;

-   PNG_CONST color_encoding *current_encoding; /* If an encoding has been set */

-   unsigned int              encoding_counter; /* For iteration */

-   int                       encoding_ignored; /* Something overwrote it */

-

-   /* Control variables used to iterate through possible encodings, the

-    * following must be set to 0 and tested by the function that uses the

-    * png_modifier because the modifier only sets it to 1 (true.)

-    */

-   unsigned int              repeat :1;   /* Repeat this transform test. */

-   unsigned int              test_uses_encoding :1;

-

-   /* Lowest sbit to test (libpng fails for sbit < 8) */

-   png_byte                 sbitlow;

-

-   /* Error control - these are the limits on errors accepted by the gamma tests

-    * below.

-    */

-   double                   maxout8;  /* Maximum output value error */

-   double                   maxabs8;  /* Absolute sample error 0..1 */

-   double                   maxcalc8; /* Absolute sample error 0..1 */

-   double                   maxpc8;   /* Percentage sample error 0..100% */

-   double                   maxout16; /* Maximum output value error */

-   double                   maxabs16; /* Absolute sample error 0..1 */

-   double                   maxcalc16;/* Absolute sample error 0..1 */

-   double                   maxpc16;  /* Percentage sample error 0..100% */

-

-   /* This is set by transforms that need to allow a higher limit, it is an

-    * internal check on pngvalid to ensure that the calculated error limits are

-    * not ridiculous; without this it is too easy to make a mistake in pngvalid

-    * that allows any value through.

-    */

-   double                   limit;    /* limit on error values, normally 4E-3 */

-

-   /* Log limits - values above this are logged, but not necessarily

-    * warned.

-    */

-   double                   log8;     /* Absolute error in 8 bits to log */

-   double                   log16;    /* Absolute error in 16 bits to log */

-

-   /* Logged 8 and 16 bit errors ('output' values): */

-   double                   error_gray_2;

-   double                   error_gray_4;

-   double                   error_gray_8;

-   double                   error_gray_16;

-   double                   error_color_8;

-   double                   error_color_16;

-   double                   error_indexed;

-

-   /* Flags: */

-   /* Whether to call png_read_update_info, not png_read_start_image, and how

-    * many times to call it.

-    */

-   int                      use_update_info;

-

-   /* Whether or not to interlace. */

-   int                      interlace_type :9; /* int, but must store '1' */

-

-   /* Run the standard tests? */

-   unsigned int             test_standard :1;

-

-   /* Run the odd-sized image and interlace read/write tests? */

-   unsigned int             test_size :1;

-

-   /* Run tests on reading with a combiniation of transforms, */

-   unsigned int             test_transform :1;

-

-   /* When to use the use_input_precision option: */

-   unsigned int             use_input_precision :1;

-   unsigned int             use_input_precision_sbit :1;

-   unsigned int             use_input_precision_16to8 :1;

-

-   /* If set assume that the calculation bit depth is set by the input

-    * precision, not the output precision.

-    */

-   unsigned int             calculations_use_input_precision :1;

-

-   /* If set assume that the calculations are done in 16 bits even if both input

-    * and output are 8 bit or less.

-    */

-   unsigned int             assume_16_bit_calculations :1;

-

-   /* Which gamma tests to run: */

-   unsigned int             test_gamma_threshold :1;

-   unsigned int             test_gamma_transform :1; /* main tests */

-   unsigned int             test_gamma_sbit :1;

-   unsigned int             test_gamma_scale16 :1;

-   unsigned int             test_gamma_background :1;

-   unsigned int             test_gamma_alpha_mode :1;

-   unsigned int             test_gamma_expand16 :1;

-   unsigned int             test_exhaustive :1;

-

-   unsigned int             log :1;   /* Log max error */

-

-   /* Buffer information, the buffer size limits the size of the chunks that can

-    * be modified - they must fit (including header and CRC) into the buffer!

-    */

-   size_t                   flush;           /* Count of bytes to flush */

-   size_t                   buffer_count;    /* Bytes in buffer */

-   size_t                   buffer_position; /* Position in buffer */

-   png_byte                 buffer[1024];

-} png_modifier;

-

-/* This returns true if the test should be stopped now because it has already

- * failed and it is running silently.

- */

-static int fail(png_modifier *pm)

-{

-   return !pm->log && !pm->this.verbose && (pm->this.nerrors > 0 ||

-       (pm->this.treat_warnings_as_errors && pm->this.nwarnings > 0));

-}

-

-static void

-modifier_init(png_modifier *pm)

-{

-   memset(pm, 0, sizeof *pm);

-   store_init(&pm->this);

-   pm->modifications = NULL;

-   pm->state = modifier_start;

-   pm->sbitlow = 1U;

-   pm->ngammas = 0;

-   pm->ngamma_tests = 0;

-   pm->gammas = 0;

-   pm->current_gamma = 0;

-   pm->encodings = 0;

-   pm->nencodings = 0;

-   pm->current_encoding = 0;

-   pm->encoding_counter = 0;

-   pm->encoding_ignored = 0;

-   pm->repeat = 0;

-   pm->test_uses_encoding = 0;

-   pm->maxout8 = pm->maxpc8 = pm->maxabs8 = pm->maxcalc8 = 0;

-   pm->maxout16 = pm->maxpc16 = pm->maxabs16 = pm->maxcalc16 = 0;

-   pm->limit = 4E-3;

-   pm->log8 = pm->log16 = 0; /* Means 'off' */

-   pm->error_gray_2 = pm->error_gray_4 = pm->error_gray_8 = 0;

-   pm->error_gray_16 = pm->error_color_8 = pm->error_color_16 = 0;

-   pm->error_indexed = 0;

-   pm->use_update_info = 0;

-   pm->interlace_type = PNG_INTERLACE_NONE;

-   pm->test_standard = 0;

-   pm->test_size = 0;

-   pm->test_transform = 0;

-   pm->use_input_precision = 0;

-   pm->use_input_precision_sbit = 0;

-   pm->use_input_precision_16to8 = 0;

-   pm->calculations_use_input_precision = 0;

-   pm->test_gamma_threshold = 0;

-   pm->test_gamma_transform = 0;

-   pm->test_gamma_sbit = 0;

-   pm->test_gamma_scale16 = 0;

-   pm->test_gamma_background = 0;

-   pm->test_gamma_alpha_mode = 0;

-   pm->test_gamma_expand16 = 0;

-   pm->test_exhaustive = 0;

-   pm->log = 0;

-

-   /* Rely on the memset for all the other fields - there are no pointers */

-}

-

-#ifdef PNG_READ_TRANSFORMS_SUPPORTED

-/* If pm->calculations_use_input_precision is set then operations will happen

- * with only 8 bit precision unless both the input and output bit depth are 16.

- *

- * If pm->assume_16_bit_calculations is set then even 8 bit calculations use 16

- * bit precision.  This only affects those of the following limits that pertain

- * to a calculation - not a digitization operation - unless the following API is

- * called directly.

- */

-static double digitize(PNG_CONST png_modifier *pm, double value,

-   int sample_depth, int do_round)

-{

-   /* 'value' is in the range 0 to 1, the result is the same value rounded to a

-    * multiple of the digitization factor - 8 or 16 bits depending on both the

-    * sample depth and the 'assume' setting.  Digitization is normally by

-    * rounding and 'do_round' should be 1, if it is 0 the digitized value will

-    * be truncated.

-    */

-   PNG_CONST unsigned int digitization_factor =

-      (pm->assume_16_bit_calculations || sample_depth == 16) ? 65535 : 255;

-

-   /* Limiting the range is done as a convenience to the caller - it's easier to

-    * do it once here than every time at the call site.

-    */

-   if (value <= 0)

-      value = 0;

-   else if (value >= 1)

-      value = 1;

-

-   value *= digitization_factor;

-   if (do_round) value += .5;

-   return floor(value)/digitization_factor;

-}

-

-static double abserr(PNG_CONST png_modifier *pm, int in_depth, int out_depth)

-{

-   /* Absolute error permitted in linear values - affected by the bit depth of

-    * the calculations.

-    */

-   if (pm->assume_16_bit_calculations || (out_depth == 16 && (in_depth == 16 ||

-      !pm->calculations_use_input_precision)))

-      return pm->maxabs16;

-   else

-      return pm->maxabs8;

-}

-

-static double calcerr(PNG_CONST png_modifier *pm, int in_depth, int out_depth)

-{

-   /* Error in the linear composition arithmetic - only relevant when

-    * composition actually happens (0 < alpha < 1).

-    */

-   if (pm->assume_16_bit_calculations || (out_depth == 16 && (in_depth == 16 ||

-      !pm->calculations_use_input_precision)))

-      return pm->maxcalc16;

-   else

-      return pm->maxcalc8;

-}

-

-static double pcerr(PNG_CONST png_modifier *pm, int in_depth, int out_depth)

-{

-   /* Percentage error permitted in the linear values.  Note that the specified

-    * value is a percentage but this routine returns a simple number.

-    */

-   if (pm->assume_16_bit_calculations || (out_depth == 16 && (in_depth == 16 ||

-      !pm->calculations_use_input_precision)))

-      return pm->maxpc16 * .01;

-   else

-      return pm->maxpc8 * .01;

-}

-

-/* Output error - the error in the encoded value.  This is determined by the

- * digitization of the output so can be +/-0.5 in the actual output value.  In

- * the expand_16 case with the current code in libpng the expand happens after

- * all the calculations are done in 8 bit arithmetic, so even though the output

- * depth is 16 the output error is determined by the 8 bit calculation.

- *

- * This limit is not determined by the bit depth of internal calculations.

- *

- * The specified parameter does *not* include the base .5 digitization error but

- * it is added here.

- */

-static double outerr(PNG_CONST png_modifier *pm, int in_depth, int out_depth)

-{

-   /* There is a serious error in the 2 and 4 bit grayscale transform because

-    * the gamma table value (8 bits) is simply shifted, not rounded, so the

-    * error in 4 bit grayscale gamma is up to the value below.  This is a hack

-    * to allow pngvalid to succeed:

-    *

-    * TODO: fix this in libpng

-    */

-   if (out_depth == 2)

-      return .73182-.5;

-

-   if (out_depth == 4)

-      return .90644-.5;

-

-   if (out_depth == 16 && (in_depth == 16 ||

-      !pm->calculations_use_input_precision))

-      return pm->maxout16;

-

-   /* This is the case where the value was calculated at 8-bit precision then

-    * scaled to 16 bits.

-    */

-   else if (out_depth == 16)

-      return pm->maxout8 * 257;

-

-   else

-      return pm->maxout8;

-}

-

-/* This does the same thing as the above however it returns the value to log,

- * rather than raising a warning.  This is useful for debugging to track down

- * exactly what set of parameters cause high error values.

- */

-static double outlog(PNG_CONST png_modifier *pm, int in_depth, int out_depth)

-{

-   /* The command line parameters are either 8 bit (0..255) or 16 bit (0..65535)

-    * and so must be adjusted for low bit depth grayscale:

-    */

-   if (out_depth <= 8)

-   {

-      if (pm->log8 == 0) /* switched off */

-         return 256;

-

-      if (out_depth < 8)

-         return pm->log8 / 255 * ((1<<out_depth)-1);

-

-      return pm->log8;

-   }

-

-   if (out_depth == 16 && (in_depth == 16 ||

-      !pm->calculations_use_input_precision))

-   {

-      if (pm->log16 == 0)

-         return 65536;

-

-      return pm->log16;

-   }

-

-   /* This is the case where the value was calculated at 8-bit precision then

-    * scaled to 16 bits.

-    */

-   if (pm->log8 == 0)

-      return 65536;

-

-   return pm->log8 * 257;

-}

-

-/* This complements the above by providing the appropriate quantization for the

- * final value.  Normally this would just be quantization to an integral value,

- * but in the 8 bit calculation case it's actually quantization to a multiple of

- * 257!

- */

-static int output_quantization_factor(PNG_CONST png_modifier *pm, int in_depth,

-   int out_depth)

-{

-   if (out_depth == 16 && in_depth != 16

-      && pm->calculations_use_input_precision)

-      return 257;

-   else

-      return 1;

-}

-

-/* One modification structure must be provided for each chunk to be modified (in

- * fact more than one can be provided if multiple separate changes are desired

- * for a single chunk.)  Modifications include adding a new chunk when a

- * suitable chunk does not exist.

- *

- * The caller of modify_fn will reset the CRC of the chunk and record 'modified'

- * or 'added' as appropriate if the modify_fn returns 1 (true).  If the

- * modify_fn is NULL the chunk is simply removed.

- */

-typedef struct png_modification

-{

-   struct png_modification *next;

-   png_uint_32              chunk;

-

-   /* If the following is NULL all matching chunks will be removed: */

-   int                    (*modify_fn)(struct png_modifier *pm,

-                               struct png_modification *me, int add);

-

-   /* If the following is set to PLTE, IDAT or IEND and the chunk has not been

-    * found and modified (and there is a modify_fn) the modify_fn will be called

-    * to add the chunk before the relevant chunk.

-    */

-   png_uint_32              add;

-   unsigned int             modified :1;     /* Chunk was modified */

-   unsigned int             added    :1;     /* Chunk was added */

-   unsigned int             removed  :1;     /* Chunk was removed */

-} png_modification;

-

-static void

-modification_reset(png_modification *pmm)

-{

-   if (pmm != NULL)

-   {

-      pmm->modified = 0;

-      pmm->added = 0;

-      pmm->removed = 0;

-      modification_reset(pmm->next);

-   }

-}

-

-static void

-modification_init(png_modification *pmm)

-{

-   memset(pmm, 0, sizeof *pmm);

-   pmm->next = NULL;

-   pmm->chunk = 0;

-   pmm->modify_fn = NULL;

-   pmm->add = 0;

-   modification_reset(pmm);

-}

-

-static void

-modifier_current_encoding(PNG_CONST png_modifier *pm, color_encoding *ce)

-{

-   if (pm->current_encoding != 0)

-      *ce = *pm->current_encoding;

-

-   else

-      memset(ce, 0, sizeof *ce);

-

-   ce->gamma = pm->current_gamma;

-}

-

-static size_t

-safecat_current_encoding(char *buffer, size_t bufsize, size_t pos,

-   PNG_CONST png_modifier *pm)

-{

-   pos = safecat_color_encoding(buffer, bufsize, pos, pm->current_encoding,

-      pm->current_gamma);

-

-   if (pm->encoding_ignored)

-      pos = safecat(buffer, bufsize, pos, "[overridden]");

-

-   return pos;

-}

-

-/* Iterate through the usefully testable color encodings.  An encoding is one

- * of:

- *

- * 1) Nothing (no color space, no gamma).

- * 2) Just a gamma value from the gamma array (including 1.0)

- * 3) A color space from the encodings array with the corresponding gamma.

- * 4) The same, but with gamma 1.0 (only really useful with 16 bit calculations)

- *

- * The iterator selects these in turn, the randomizer selects one at random,

- * which is used depends on the setting of the 'test_exhaustive' flag.  Notice

- * that this function changes the colour space encoding so it must only be

- * called on completion of the previous test.  This is what 'modifier_reset'

- * does, below.

- *

- * After the function has been called the 'repeat' flag will still be set; the

- * caller of modifier_reset must reset it at the start of each run of the test!

- */

-static unsigned int

-modifier_total_encodings(PNG_CONST png_modifier *pm)

-{

-   return 1 +                 /* (1) nothing */

-      pm->ngammas +           /* (2) gamma values to test */

-      pm->nencodings +        /* (3) total number of encodings */

-      /* The following test only works after the first time through the

-       * png_modifier code because 'bit_depth' is set when the IHDR is read.

-       * modifier_reset, below, preserves the setting until after it has called

-       * the iterate function (also below.)

-       *

-       * For this reason do not rely on this function outside a call to

-       * modifier_reset.

-       */

-      ((pm->bit_depth == 16 || pm->assume_16_bit_calculations) ?

-         pm->nencodings : 0); /* (4) encodings with gamma == 1.0 */

-}

-

-static void

-modifier_encoding_iterate(png_modifier *pm)

-{

-   if (!pm->repeat && /* Else something needs the current encoding again. */

-      pm->test_uses_encoding) /* Some transform is encoding dependent */

-   {

-      if (pm->test_exhaustive)

-      {

-         if (++pm->encoding_counter >= modifier_total_encodings(pm))

-            pm->encoding_counter = 0; /* This will stop the repeat */

-      }

-

-      else

-      {

-         /* Not exhaustive - choose an encoding at random; generate a number in

-          * the range 1..(max-1), so the result is always non-zero:

-          */

-         if (pm->encoding_counter == 0)

-            pm->encoding_counter = random_mod(modifier_total_encodings(pm)-1)+1;

-         else

-            pm->encoding_counter = 0;

-      }

-

-      if (pm->encoding_counter > 0)

-         pm->repeat = 1;

-   }

-

-   else if (!pm->repeat)

-      pm->encoding_counter = 0;

-}

-

-static void

-modifier_reset(png_modifier *pm)

-{

-   store_read_reset(&pm->this);

-   pm->limit = 4E-3;

-   pm->pending_len = pm->pending_chunk = 0;

-   pm->flush = pm->buffer_count = pm->buffer_position = 0;

-   pm->modifications = NULL;

-   pm->state = modifier_start;

-   modifier_encoding_iterate(pm);

-   /* The following must be set in the next run.  In particular

-    * test_uses_encodings must be set in the _ini function of each transform

-    * that looks at the encodings.  (Not the 'add' function!)

-    */

-   pm->test_uses_encoding = 0;

-   pm->current_gamma = 0;

-   pm->current_encoding = 0;

-   pm->encoding_ignored = 0;

-   /* These only become value after IHDR is read: */

-   pm->bit_depth = pm->colour_type = 0;

-}

-

-/* The following must be called before anything else to get the encoding set up

- * on the modifier.  In particular it must be called before the transform init

- * functions are called.

- */

-static void

-modifier_set_encoding(png_modifier *pm)

-{

-   /* Set the encoding to the one specified by the current encoding counter,

-    * first clear out all the settings - this corresponds to an encoding_counter

-    * of 0.

-    */

-   pm->current_gamma = 0;

-   pm->current_encoding = 0;

-   pm->encoding_ignored = 0; /* not ignored yet - happens in _ini functions. */

-

-   /* Now, if required, set the gamma and encoding fields. */

-   if (pm->encoding_counter > 0)

-   {

-      /* The gammas[] array is an array of screen gammas, not encoding gammas,

-       * so we need the inverse:

-       */

-      if (pm->encoding_counter <= pm->ngammas)

-         pm->current_gamma = 1/pm->gammas[pm->encoding_counter-1];

-

-      else

-      {

-         unsigned int i = pm->encoding_counter - pm->ngammas;

-

-         if (i >= pm->nencodings)

-         {

-            i %= pm->nencodings;

-            pm->current_gamma = 1; /* Linear, only in the 16 bit case */

-         }

-

-         else

-            pm->current_gamma = pm->encodings[i].gamma;

-

-         pm->current_encoding = pm->encodings + i;

-      }

-   }

-}

-

-/* Enquiry functions to find out what is set.  Notice that there is an implicit

- * assumption below that the first encoding in the list is the one for sRGB.

- */

-static int

-modifier_color_encoding_is_sRGB(PNG_CONST png_modifier *pm)

-{

-   return pm->current_encoding != 0 && pm->current_encoding == pm->encodings &&

-      pm->current_encoding->gamma == pm->current_gamma;

-}

-

-static int

-modifier_color_encoding_is_set(PNG_CONST png_modifier *pm)

-{

-   return pm->current_gamma != 0;

-}

-

-/* Convenience macros. */

-#define CHUNK(a,b,c,d) (((a)<<24)+((b)<<16)+((c)<<8)+(d))

-#define CHUNK_IHDR CHUNK(73,72,68,82)

-#define CHUNK_PLTE CHUNK(80,76,84,69)

-#define CHUNK_IDAT CHUNK(73,68,65,84)

-#define CHUNK_IEND CHUNK(73,69,78,68)

-#define CHUNK_cHRM CHUNK(99,72,82,77)

-#define CHUNK_gAMA CHUNK(103,65,77,65)

-#define CHUNK_sBIT CHUNK(115,66,73,84)

-#define CHUNK_sRGB CHUNK(115,82,71,66)

-

-/* The guts of modification are performed during a read. */

-static void

-modifier_crc(png_bytep buffer)

-{

-   /* Recalculate the chunk CRC - a complete chunk must be in

-    * the buffer, at the start.

-    */

-   uInt datalen = png_get_uint_32(buffer);

-   uLong crc = crc32(0, buffer+4, datalen+4);

-   /* The cast to png_uint_32 is safe because a crc32 is always a 32 bit value.

-    */

-   png_save_uint_32(buffer+datalen+8, (png_uint_32)crc);

-}

-

-static void

-modifier_setbuffer(png_modifier *pm)

-{

-   modifier_crc(pm->buffer);

-   pm->buffer_count = png_get_uint_32(pm->buffer)+12;

-   pm->buffer_position = 0;

-}

-

-/* Separate the callback into the actual implementation (which is passed the

- * png_modifier explicitly) and the callback, which gets the modifier from the

- * png_struct.

- */

-static void

-modifier_read_imp(png_modifier *pm, png_bytep pb, png_size_t st)

-{

-   while (st > 0)

-   {

-      size_t cb;

-      png_uint_32 len, chunk;

-      png_modification *mod;

-

-      if (pm->buffer_position >= pm->buffer_count) switch (pm->state)

-      {

-         static png_byte sign[8] = { 137, 80, 78, 71, 13, 10, 26, 10 };

-         case modifier_start:

-            store_read_imp(&pm->this, pm->buffer, 8); /* size of signature. */

-            pm->buffer_count = 8;

-            pm->buffer_position = 0;

-

-            if (memcmp(pm->buffer, sign, 8) != 0)

-               png_error(pm->this.pread, "invalid PNG file signature");

-            pm->state = modifier_signature;

-            break;

-

-         case modifier_signature:

-            store_read_imp(&pm->this, pm->buffer, 13+12); /* size of IHDR */

-            pm->buffer_count = 13+12;

-            pm->buffer_position = 0;

-

-            if (png_get_uint_32(pm->buffer) != 13 ||

-                png_get_uint_32(pm->buffer+4) != CHUNK_IHDR)

-               png_error(pm->this.pread, "invalid IHDR");

-

-            /* Check the list of modifiers for modifications to the IHDR. */

-            mod = pm->modifications;

-            while (mod != NULL)

-            {

-               if (mod->chunk == CHUNK_IHDR && mod->modify_fn &&

-                   (*mod->modify_fn)(pm, mod, 0))

-                  {

-                  mod->modified = 1;

-                  modifier_setbuffer(pm);

-                  }

-

-               /* Ignore removal or add if IHDR! */

-               mod = mod->next;

-            }

-

-            /* Cache information from the IHDR (the modified one.) */

-            pm->bit_depth = pm->buffer[8+8];

-            pm->colour_type = pm->buffer[8+8+1];

-

-            pm->state = modifier_IHDR;

-            pm->flush = 0;

-            break;

-

-         case modifier_IHDR:

-         default:

-            /* Read a new chunk and process it until we see PLTE, IDAT or

-             * IEND.  'flush' indicates that there is still some data to

-             * output from the preceding chunk.

-             */

-            if ((cb = pm->flush) > 0)

-            {

-               if (cb > st) cb = st;

-               pm->flush -= cb;

-               store_read_imp(&pm->this, pb, cb);

-               pb += cb;

-               st -= cb;

-               if (st == 0) return;

-            }

-

-            /* No more bytes to flush, read a header, or handle a pending

-             * chunk.

-             */

-            if (pm->pending_chunk != 0)

-            {

-               png_save_uint_32(pm->buffer, pm->pending_len);

-               png_save_uint_32(pm->buffer+4, pm->pending_chunk);

-               pm->pending_len = 0;

-               pm->pending_chunk = 0;

-            }

-            else

-               store_read_imp(&pm->this, pm->buffer, 8);

-

-            pm->buffer_count = 8;

-            pm->buffer_position = 0;

-

-            /* Check for something to modify or a terminator chunk. */

-            len = png_get_uint_32(pm->buffer);

-            chunk = png_get_uint_32(pm->buffer+4);

-

-            /* Terminators first, they may have to be delayed for added

-             * chunks

-             */

-            if (chunk == CHUNK_PLTE || chunk == CHUNK_IDAT ||

-                chunk == CHUNK_IEND)

-            {

-               mod = pm->modifications;

-

-               while (mod != NULL)

-               {

-                  if ((mod->add == chunk ||

-                      (mod->add == CHUNK_PLTE && chunk == CHUNK_IDAT)) &&

-                      mod->modify_fn != NULL && !mod->modified && !mod->added)

-                  {

-                     /* Regardless of what the modify function does do not run

-                      * this again.

-                      */

-                     mod->added = 1;

-

-                     if ((*mod->modify_fn)(pm, mod, 1 /*add*/))

-                     {

-                        /* Reset the CRC on a new chunk */

-                        if (pm->buffer_count > 0)

-                           modifier_setbuffer(pm);

-

-                        else

-                           {

-                           pm->buffer_position = 0;

-                           mod->removed = 1;

-                           }

-

-                        /* The buffer has been filled with something (we assume)

-                         * so output this.  Pend the current chunk.

-                         */

-                        pm->pending_len = len;

-                        pm->pending_chunk = chunk;

-                        break; /* out of while */

-                     }

-                  }

-

-                  mod = mod->next;

-               }

-

-               /* Don't do any further processing if the buffer was modified -

-                * otherwise the code will end up modifying a chunk that was

-                * just added.

-                */

-               if (mod != NULL)

-                  break; /* out of switch */

-            }

-

-            /* If we get to here then this chunk may need to be modified.  To

-             * do this it must be less than 1024 bytes in total size, otherwise

-             * it just gets flushed.

-             */

-            if (len+12 <= sizeof pm->buffer)

-            {

-               store_read_imp(&pm->this, pm->buffer+pm->buffer_count,

-                   len+12-pm->buffer_count);

-               pm->buffer_count = len+12;

-

-               /* Check for a modification, else leave it be. */

-               mod = pm->modifications;

-               while (mod != NULL)

-               {

-                  if (mod->chunk == chunk)

-                  {

-                     if (mod->modify_fn == NULL)

-                     {

-                        /* Remove this chunk */

-                        pm->buffer_count = pm->buffer_position = 0;

-                        mod->removed = 1;

-                        break; /* Terminate the while loop */

-                     }

-

-                     else if ((*mod->modify_fn)(pm, mod, 0))

-                     {

-                        mod->modified = 1;

-                        /* The chunk may have been removed: */

-                        if (pm->buffer_count == 0)

-                        {

-                           pm->buffer_position = 0;

-                           break;

-                        }

-                        modifier_setbuffer(pm);

-                     }

-                  }

-

-                  mod = mod->next;

-               }

-            }

-

-            else

-               pm->flush = len+12 - pm->buffer_count; /* data + crc */

-

-            /* Take the data from the buffer (if there is any). */

-            break;

-      }

-

-      /* Here to read from the modifier buffer (not directly from

-       * the store, as in the flush case above.)

-       */

-      cb = pm->buffer_count - pm->buffer_position;

-

-      if (cb > st)

-         cb = st;

-

-      memcpy(pb, pm->buffer + pm->buffer_position, cb);

-      st -= cb;

-      pb += cb;

-      pm->buffer_position += cb;

-   }

-}

-

-/* The callback: */

-static void

-modifier_read(png_structp pp, png_bytep pb, png_size_t st)

-{

-   png_modifier *pm = voidcast(png_modifier*, png_get_io_ptr(pp));

-

-   if (pm == NULL || pm->this.pread != pp)

-      png_error(pp, "bad modifier_read call");

-

-   modifier_read_imp(pm, pb, st);

-}

-

-/* Like store_progressive_read but the data is getting changed as we go so we

- * need a local buffer.

- */

-static void

-modifier_progressive_read(png_modifier *pm, png_structp pp, png_infop pi)

-{

-   if (pm->this.pread != pp || pm->this.current == NULL ||

-       pm->this.next == NULL)

-      png_error(pp, "store state damaged (progressive)");

-

-   /* This is another Horowitz and Hill random noise generator.  In this case

-    * the aim is to stress the progressive reader with truly horrible variable

-    * buffer sizes in the range 1..500, so a sequence of 9 bit random numbers

-    * is generated.  We could probably just count from 1 to 32767 and get as

-    * good a result.

-    */

-   for (;;)

-   {

-      static png_uint_32 noise = 1;

-      png_size_t cb, cbAvail;

-      png_byte buffer[512];

-

-      /* Generate 15 more bits of stuff: */

-      noise = (noise << 9) | ((noise ^ (noise >> (9-5))) & 0x1ff);

-      cb = noise & 0x1ff;

-

-      /* Check that this number of bytes are available (in the current buffer.)

-       * (This doesn't quite work - the modifier might delete a chunk; unlikely

-       * but possible, it doesn't happen at present because the modifier only

-       * adds chunks to standard images.)

-       */

-      cbAvail = store_read_buffer_avail(&pm->this);

-      if (pm->buffer_count > pm->buffer_position)

-         cbAvail += pm->buffer_count - pm->buffer_position;

-

-      if (cb > cbAvail)

-      {

-         /* Check for EOF: */

-         if (cbAvail == 0)

-            break;

-

-         cb = cbAvail;

-      }

-

-      modifier_read_imp(pm, buffer, cb);

-      png_process_data(pp, pi, buffer, cb);

-   }

-

-   /* Check the invariants at the end (if this fails it's a problem in this

-    * file!)

-    */

-   if (pm->buffer_count > pm->buffer_position ||

-       pm->this.next != &pm->this.current->data ||

-       pm->this.readpos < pm->this.current->datacount)

-      png_error(pp, "progressive read implementation error");

-}

-

-/* Set up a modifier. */

-static png_structp

-set_modifier_for_read(png_modifier *pm, png_infopp ppi, png_uint_32 id,

-    PNG_CONST char *name)

-{

-   /* Do this first so that the modifier fields are cleared even if an error

-    * happens allocating the png_struct.  No allocation is done here so no

-    * cleanup is required.

-    */

-   pm->state = modifier_start;

-   pm->bit_depth = 0;

-   pm->colour_type = 255;

-

-   pm->pending_len = 0;

-   pm->pending_chunk = 0;

-   pm->flush = 0;

-   pm->buffer_count = 0;

-   pm->buffer_position = 0;

-

-   return set_store_for_read(&pm->this, ppi, id, name);

-}

-

-

-/******************************** MODIFICATIONS *******************************/

-/* Standard modifications to add chunks.  These do not require the _SUPPORTED

- * macros because the chunks can be there regardless of whether this specific

- * libpng supports them.

- */

-typedef struct gama_modification

-{

-   png_modification this;

-   png_fixed_point  gamma;

-} gama_modification;

-

-static int

-gama_modify(png_modifier *pm, png_modification *me, int add)

-{

-   UNUSED(add)

-   /* This simply dumps the given gamma value into the buffer. */

-   png_save_uint_32(pm->buffer, 4);

-   png_save_uint_32(pm->buffer+4, CHUNK_gAMA);

-   png_save_uint_32(pm->buffer+8, ((gama_modification*)me)->gamma);

-   return 1;

-}

-

-static void

-gama_modification_init(gama_modification *me, png_modifier *pm, double gammad)

-{

-   double g;

-

-   modification_init(&me->this);

-   me->this.chunk = CHUNK_gAMA;

-   me->this.modify_fn = gama_modify;

-   me->this.add = CHUNK_PLTE;

-   g = fix(gammad);

-   me->gamma = (png_fixed_point)g;

-   me->this.next = pm->modifications;

-   pm->modifications = &me->this;

-}

-

-typedef struct chrm_modification

-{

-   png_modification          this;

-   PNG_CONST color_encoding *encoding;

-   png_fixed_point           wx, wy, rx, ry, gx, gy, bx, by;

-} chrm_modification;

-

-static int

-chrm_modify(png_modifier *pm, png_modification *me, int add)

-{

-   UNUSED(add)

-   /* As with gAMA this just adds the required cHRM chunk to the buffer. */

-   png_save_uint_32(pm->buffer   , 32);

-   png_save_uint_32(pm->buffer+ 4, CHUNK_cHRM);

-   png_save_uint_32(pm->buffer+ 8, ((chrm_modification*)me)->wx);

-   png_save_uint_32(pm->buffer+12, ((chrm_modification*)me)->wy);

-   png_save_uint_32(pm->buffer+16, ((chrm_modification*)me)->rx);

-   png_save_uint_32(pm->buffer+20, ((chrm_modification*)me)->ry);

-   png_save_uint_32(pm->buffer+24, ((chrm_modification*)me)->gx);

-   png_save_uint_32(pm->buffer+28, ((chrm_modification*)me)->gy);

-   png_save_uint_32(pm->buffer+32, ((chrm_modification*)me)->bx);

-   png_save_uint_32(pm->buffer+36, ((chrm_modification*)me)->by);

-   return 1;

-}

-

-static void

-chrm_modification_init(chrm_modification *me, png_modifier *pm,

-   PNG_CONST color_encoding *encoding)

-{

-   CIE_color white = white_point(encoding);

-

-   /* Original end points: */

-   me->encoding = encoding;

-

-   /* Chromaticities (in fixed point): */

-   me->wx = fix(chromaticity_x(white));

-   me->wy = fix(chromaticity_y(white));

-

-   me->rx = fix(chromaticity_x(encoding->red));

-   me->ry = fix(chromaticity_y(encoding->red));

-   me->gx = fix(chromaticity_x(encoding->green));

-   me->gy = fix(chromaticity_y(encoding->green));

-   me->bx = fix(chromaticity_x(encoding->blue));

-   me->by = fix(chromaticity_y(encoding->blue));

-

-   modification_init(&me->this);

-   me->this.chunk = CHUNK_cHRM;

-   me->this.modify_fn = chrm_modify;

-   me->this.add = CHUNK_PLTE;

-   me->this.next = pm->modifications;

-   pm->modifications = &me->this;

-}

-

-typedef struct srgb_modification

-{

-   png_modification this;

-   png_byte         intent;

-} srgb_modification;

-

-static int

-srgb_modify(png_modifier *pm, png_modification *me, int add)

-{

-   UNUSED(add)

-   /* As above, ignore add and just make a new chunk */

-   png_save_uint_32(pm->buffer, 1);

-   png_save_uint_32(pm->buffer+4, CHUNK_sRGB);

-   pm->buffer[8] = ((srgb_modification*)me)->intent;

-   return 1;

-}

-

-static void

-srgb_modification_init(srgb_modification *me, png_modifier *pm, png_byte intent)

-{

-   modification_init(&me->this);

-   me->this.chunk = CHUNK_sBIT;

-

-   if (intent <= 3) /* if valid, else *delete* sRGB chunks */

-   {

-      me->this.modify_fn = srgb_modify;

-      me->this.add = CHUNK_PLTE;

-      me->intent = intent;

-   }

-

-   else

-   {

-      me->this.modify_fn = 0;

-      me->this.add = 0;

-      me->intent = 0;

-   }

-

-   me->this.next = pm->modifications;

-   pm->modifications = &me->this;

-}

-

-typedef struct sbit_modification

-{

-   png_modification this;

-   png_byte         sbit;

-} sbit_modification;

-

-static int

-sbit_modify(png_modifier *pm, png_modification *me, int add)

-{

-   png_byte sbit = ((sbit_modification*)me)->sbit;

-   if (pm->bit_depth > sbit)

-   {

-      int cb = 0;

-      switch (pm->colour_type)

-      {

-         case 0:

-            cb = 1;

-            break;

-

-         case 2:

-         case 3:

-            cb = 3;

-            break;

-

-         case 4:

-            cb = 2;

-            break;

-

-         case 6:

-            cb = 4;

-            break;

-

-         default:

-            png_error(pm->this.pread,

-               "unexpected colour type in sBIT modification");

-      }

-

-      png_save_uint_32(pm->buffer, cb);

-      png_save_uint_32(pm->buffer+4, CHUNK_sBIT);

-

-      while (cb > 0)

-         (pm->buffer+8)[--cb] = sbit;

-

-      return 1;

-   }

-   else if (!add)

-   {

-      /* Remove the sBIT chunk */

-      pm->buffer_count = pm->buffer_position = 0;

-      return 1;

-   }

-   else

-      return 0; /* do nothing */

-}

-

-static void

-sbit_modification_init(sbit_modification *me, png_modifier *pm, png_byte sbit)

-{

-   modification_init(&me->this);

-   me->this.chunk = CHUNK_sBIT;

-   me->this.modify_fn = sbit_modify;

-   me->this.add = CHUNK_PLTE;

-   me->sbit = sbit;

-   me->this.next = pm->modifications;

-   pm->modifications = &me->this;

-}

-#endif /* PNG_READ_TRANSFORMS_SUPPORTED */

-

-/***************************** STANDARD PNG FILES *****************************/

-/* Standard files - write and save standard files. */

-/* There are two basic forms of standard images.  Those which attempt to have

- * all the possible pixel values (not possible for 16bpp images, but a range of

- * values are produced) and those which have a range of image sizes.  The former

- * are used for testing transforms, in particular gamma correction and bit

- * reduction and increase.  The latter are reserved for testing the behavior of

- * libpng with respect to 'odd' image sizes - particularly small images where

- * rows become 1 byte and interlace passes disappear.

- *

- * The first, most useful, set are the 'transform' images, the second set of

- * small images are the 'size' images.

- *

- * The transform files are constructed with rows which fit into a 1024 byte row

- * buffer.  This makes allocation easier below.  Further regardless of the file

- * format every row has 128 pixels (giving 1024 bytes for 64bpp formats).

- *

- * Files are stored with no gAMA or sBIT chunks, with a PLTE only when needed

- * and with an ID derived from the colour type, bit depth and interlace type

- * as above (FILEID).  The width (128) and height (variable) are not stored in

- * the FILEID - instead the fields are set to 0, indicating a transform file.

- *

- * The size files ar constructed with rows a maximum of 128 bytes wide, allowing

- * a maximum width of 16 pixels (for the 64bpp case.)  They also have a maximum

- * height of 16 rows.  The width and height are stored in the FILEID and, being

- * non-zero, indicate a size file.

- *

- * For palette image (colour type 3) multiple transform images are stored with

- * the same bit depth to allow testing of more colour combinations -

- * particularly important for testing the gamma code because libpng uses a

- * different code path for palette images.  For size images a single palette is

- * used.

- */

-

-/* Make a 'standard' palette.  Because there are only 256 entries in a palette

- * (maximum) this actually makes a random palette in the hope that enough tests

- * will catch enough errors.  (Note that the same palette isn't produced every

- * time for the same test - it depends on what previous tests have been run -

- * but a given set of arguments to pngvalid will always produce the same palette

- * at the same test!  This is why pseudo-random number generators are useful for

- * testing.)

- *

- * The store must be open for write when this is called, otherwise an internal

- * error will occur.  This routine contains its own magic number seed, so the

- * palettes generated don't change if there are intervening errors (changing the

- * calls to the store_mark seed.)

- */

-static store_palette_entry *

-make_standard_palette(png_store* ps, int npalette, int do_tRNS)

-{

-   static png_uint_32 palette_seed[2] = { 0x87654321, 9 };

-

-   int i = 0;

-   png_byte values[256][4];

-

-   /* Always put in black and white plus the six primary and secondary colors.

-    */

-   for (; i<8; ++i)

-   {

-      values[i][1] = (i&1) ? 255 : 0;

-      values[i][2] = (i&2) ? 255 : 0;

-      values[i][3] = (i&4) ? 255 : 0;

-   }

-

-   /* Then add 62 grays (one quarter of the remaining 256 slots). */

-   {

-      int j = 0;

-      png_byte random_bytes[4];

-      png_byte need[256];

-

-      need[0] = 0; /*got black*/

-      memset(need+1, 1, (sizeof need)-2); /*need these*/

-      need[255] = 0; /*but not white*/

-

-      while (i<70)

-      {

-         png_byte b;

-

-         if (j==0)

-         {

-            make_four_random_bytes(palette_seed, random_bytes);

-            j = 4;

-         }

-

-         b = random_bytes[--j];

-         if (need[b])

-         {

-            values[i][1] = b;

-            values[i][2] = b;

-            values[i++][3] = b;

-         }

-      }

-   }

-

-   /* Finally add 192 colors at random - don't worry about matches to things we

-    * already have, chance is less than 1/65536.  Don't worry about grays,

-    * chance is the same, so we get a duplicate or extra gray less than 1 time

-    * in 170.

-    */

-   for (; i<256; ++i)

-      make_four_random_bytes(palette_seed, values[i]);

-

-   /* Fill in the alpha values in the first byte.  Just use all possible values

-    * (0..255) in an apparently random order:

-    */

-   {

-      store_palette_entry *palette;

-      png_byte selector[4];

-

-      make_four_random_bytes(palette_seed, selector);

-

-      if (do_tRNS)

-         for (i=0; i<256; ++i)

-            values[i][0] = (png_byte)(i ^ selector[0]);

-

-      else

-         for (i=0; i<256; ++i)

-            values[i][0] = 255; /* no transparency/tRNS chunk */

-

-      /* 'values' contains 256 ARGB values, but we only need 'npalette'.

-       * 'npalette' will always be a power of 2: 2, 4, 16 or 256.  In the low

-       * bit depth cases select colors at random, else it is difficult to have

-       * a set of low bit depth palette test with any chance of a reasonable

-       * range of colors.  Do this by randomly permuting values into the low

-       * 'npalette' entries using an XOR mask generated here.  This also

-       * permutes the npalette == 256 case in a potentially useful way (there is

-       * no relationship between palette index and the color value therein!)

-       */

-      palette = store_write_palette(ps, npalette);

-

-      for (i=0; i<npalette; ++i)

-      {

-         palette[i].alpha = values[i ^ selector[1]][0];

-         palette[i].red   = values[i ^ selector[1]][1];

-         palette[i].green = values[i ^ selector[1]][2];

-         palette[i].blue  = values[i ^ selector[1]][3];

-      }

-

-      return palette;

-   }

-}

-

-/* Initialize a standard palette on a write stream.  The 'do_tRNS' argument

- * indicates whether or not to also set the tRNS chunk.

- */

-static void

-init_standard_palette(png_store *ps, png_structp pp, png_infop pi, int npalette,

-   int do_tRNS)

-{

-   store_palette_entry *ppal = make_standard_palette(ps, npalette, do_tRNS);

-

-   {

-      int i;

-      png_color palette[256];

-

-      /* Set all entries to detect overread errors. */

-      for (i=0; i<npalette; ++i)

-      {

-         palette[i].red = ppal[i].red;

-         palette[i].green = ppal[i].green;

-         palette[i].blue = ppal[i].blue;

-      }

-

-      /* Just in case fill in the rest with detectable values: */

-      for (; i<256; ++i)

-         palette[i].red = palette[i].green = palette[i].blue = 42;

-

-      png_set_PLTE(pp, pi, palette, npalette);

-   }

-

-   if (do_tRNS)

-   {

-      int i, j;

-      png_byte tRNS[256];

-

-      /* Set all the entries, but skip trailing opaque entries */

-      for (i=j=0; i<npalette; ++i)

-         if ((tRNS[i] = ppal[i].alpha) < 255)

-            j = i+1;

-

-      /* Fill in the remainder with a detectable value: */

-      for (; i<256; ++i)

-         tRNS[i] = 24;

-

-      if (j > 0)

-         png_set_tRNS(pp, pi, tRNS, j, 0/*color*/);

-   }

-}

-

-/* The number of passes is related to the interlace type. There was no libpng

- * API to determine this prior to 1.5, so we need an inquiry function:

- */

-static int

-npasses_from_interlace_type(png_structp pp, int interlace_type)

-{

-   switch (interlace_type)

-   {

-   default:

-      png_error(pp, "invalid interlace type");

-

-   case PNG_INTERLACE_NONE:

-      return 1;

-

-   case PNG_INTERLACE_ADAM7:

-      return PNG_INTERLACE_ADAM7_PASSES;

-   }

-}

-

-static unsigned int

-bit_size(png_structp pp, png_byte colour_type, png_byte bit_depth)

-{

-   switch (colour_type)

-   {

-      default: png_error(pp, "invalid color type");

-

-      case 0:  return bit_depth;

-

-      case 2:  return 3*bit_depth;

-

-      case 3:  return bit_depth;

-

-      case 4:  return 2*bit_depth;

-

-      case 6:  return 4*bit_depth;

-   }

-}

-

-#define TRANSFORM_WIDTH  128U

-#define TRANSFORM_ROWMAX (TRANSFORM_WIDTH*8U)

-#define SIZE_ROWMAX (16*8U) /* 16 pixels, max 8 bytes each - 128 bytes */

-#define STANDARD_ROWMAX TRANSFORM_ROWMAX /* The larger of the two */

-#define SIZE_HEIGHTMAX 16 /* Maximum range of size images */

-

-static size_t

-transform_rowsize(png_structp pp, png_byte colour_type, png_byte bit_depth)

-{

-   return (TRANSFORM_WIDTH * bit_size(pp, colour_type, bit_depth)) / 8;

-}

-

-/* transform_width(pp, colour_type, bit_depth) current returns the same number

- * every time, so just use a macro:

- */

-#define transform_width(pp, colour_type, bit_depth) TRANSFORM_WIDTH

-

-static png_uint_32

-transform_height(png_structp pp, png_byte colour_type, png_byte bit_depth)

-{

-   switch (bit_size(pp, colour_type, bit_depth))

-   {

-      case 1:

-      case 2:

-      case 4:

-         return 1;   /* Total of 128 pixels */

-

-      case 8:

-         return 2;   /* Total of 256 pixels/bytes */

-

-      case 16:

-         return 512; /* Total of 65536 pixels */

-

-      case 24:

-      case 32:

-         return 512; /* 65536 pixels */

-

-      case 48:

-      case 64:

-         return 2048;/* 4 x 65536 pixels. */

-#        define TRANSFORM_HEIGHTMAX 2048

-

-      default:

-         return 0;   /* Error, will be caught later */

-   }

-}

-

-/* The following can only be defined here, now we have the definitions

- * of the transform image sizes.

- */

-static png_uint_32

-standard_width(png_structp pp, png_uint_32 id)

-{

-   png_uint_32 width = WIDTH_FROM_ID(id);

-   UNUSED(pp)

-

-   if (width == 0)

-      width = transform_width(pp, COL_FROM_ID(id), DEPTH_FROM_ID(id));

-

-   return width;

-}

-

-static png_uint_32

-standard_height(png_structp pp, png_uint_32 id)

-{

-   png_uint_32 height = HEIGHT_FROM_ID(id);

-

-   if (height == 0)

-      height = transform_height(pp, COL_FROM_ID(id), DEPTH_FROM_ID(id));

-

-   return height;

-}

-

-static png_uint_32

-standard_rowsize(png_structp pp, png_uint_32 id)

-{

-   png_uint_32 width = standard_width(pp, id);

-

-   /* This won't overflow: */

-   width *= bit_size(pp, COL_FROM_ID(id), DEPTH_FROM_ID(id));

-   return (width + 7) / 8;

-}

-

-static void

-transform_row(png_structp pp, png_byte buffer[TRANSFORM_ROWMAX],

-   png_byte colour_type, png_byte bit_depth, png_uint_32 y)

-{

-   png_uint_32 v = y << 7;

-   png_uint_32 i = 0;

-

-   switch (bit_size(pp, colour_type, bit_depth))

-   {

-      case 1:

-         while (i<128/8) buffer[i] = v & 0xff, v += 17, ++i;

-         return;

-

-      case 2:

-         while (i<128/4) buffer[i] = v & 0xff, v += 33, ++i;

-         return;

-

-      case 4:

-         while (i<128/2) buffer[i] = v & 0xff, v += 65, ++i;

-         return;

-

-      case 8:

-         /* 256 bytes total, 128 bytes in each row set as follows: */

-         while (i<128) buffer[i] = v & 0xff, ++v, ++i;

-         return;

-

-      case 16:

-         /* Generate all 65536 pixel values in order, which includes the 8 bit

-          * GA case as well as the 16 bit G case.

-          */

-         while (i<128)

-            buffer[2*i] = (v>>8) & 0xff, buffer[2*i+1] = v & 0xff, ++v, ++i;

-

-         return;

-

-      case 24:

-         /* 65535 pixels, but rotate the values. */

-         while (i<128)

-         {

-            /* Three bytes per pixel, r, g, b, make b by r^g */

-            buffer[3*i+0] = (v >> 8) & 0xff;

-            buffer[3*i+1] = v & 0xff;

-            buffer[3*i+2] = ((v >> 8) ^ v) & 0xff;

-            ++v;

-            ++i;

-         }

-

-         return;

-

-      case 32:

-         /* 65535 pixels, r, g, b, a; just replicate */

-         while (i<128)

-         {

-            buffer[4*i+0] = (v >> 8) & 0xff;

-            buffer[4*i+1] = v & 0xff;

-            buffer[4*i+2] = (v >> 8) & 0xff;

-            buffer[4*i+3] = v & 0xff;

-            ++v;

-            ++i;

-         }

-

-         return;

-

-      case 48:

-         /* y is maximum 2047, giving 4x65536 pixels, make 'r' increase by 1 at

-          * each pixel, g increase by 257 (0x101) and 'b' by 0x1111:

-          */

-         while (i<128)

-         {

-            png_uint_32 t = v++;

-            buffer[6*i+0] = (t >> 8) & 0xff;

-            buffer[6*i+1] = t & 0xff;

-            t *= 257;

-            buffer[6*i+2] = (t >> 8) & 0xff;

-            buffer[6*i+3] = t & 0xff;

-            t *= 17;

-            buffer[6*i+4] = (t >> 8) & 0xff;

-            buffer[6*i+5] = t & 0xff;

-            ++i;

-         }

-

-         return;

-

-      case 64:

-         /* As above in the 32 bit case. */

-         while (i<128)

-         {

-            png_uint_32 t = v++;

-            buffer[8*i+0] = (t >> 8) & 0xff;

-            buffer[8*i+1] = t & 0xff;

-            buffer[8*i+4] = (t >> 8) & 0xff;

-            buffer[8*i+5] = t & 0xff;

-            t *= 257;

-            buffer[8*i+2] = (t >> 8) & 0xff;

-            buffer[8*i+3] = t & 0xff;

-            buffer[8*i+6] = (t >> 8) & 0xff;

-            buffer[8*i+7] = t & 0xff;

-            ++i;

-         }

-         return;

-

-      default:

-         break;

-   }

-

-   png_error(pp, "internal error");

-}

-

-/* This is just to do the right cast - could be changed to a function to check

- * 'bd' but there isn't much point.

- */

-#define DEPTH(bd) ((png_byte)(1U << (bd)))

-

-/* Make a standardized image given a an image colour type, bit depth and

- * interlace type.  The standard images have a very restricted range of

- * rows and heights and are used for testing transforms rather than image

- * layout details.  See make_size_images below for a way to make images

- * that test odd sizes along with the libpng interlace handling.

- */

-static void

-make_transform_image(png_store* PNG_CONST ps, png_byte PNG_CONST colour_type,

-    png_byte PNG_CONST bit_depth, int palette_number, int interlace_type,

-    png_const_charp name)

-{

-   context(ps, fault);

-

-   Try

-   {

-      png_infop pi;

-      png_structp pp = set_store_for_write(ps, &pi, name);

-      png_uint_32 h;

-

-      /* In the event of a problem return control to the Catch statement below

-       * to do the clean up - it is not possible to 'return' directly from a Try

-       * block.

-       */

-      if (pp == NULL)

-         Throw ps;

-

-      h = transform_height(pp, colour_type, bit_depth);

-

-      png_set_IHDR(pp, pi, transform_width(pp, colour_type, bit_depth), h,

-         bit_depth, colour_type, interlace_type,

-         PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);

-

-#ifdef PNG_TEXT_SUPPORTED

-      {

-         static char key[] = "image name"; /* must be writeable */

-         size_t pos;

-         png_text text;

-         char copy[FILE_NAME_SIZE];

-

-         /* Use a compressed text string to test the correct interaction of text

-          * compression and IDAT compression.

-          */

-         text.compression = PNG_TEXT_COMPRESSION_zTXt;

-         text.key = key;

-         /* Yuck: the text must be writable! */

-         pos = safecat(copy, sizeof copy, 0, ps->wname);

-         text.text = copy;

-         text.text_length = pos;

-         text.itxt_length = 0;

-         text.lang = 0;

-         text.lang_key = 0;

-

-         png_set_text(pp, pi, &text, 1);

-      }

-#endif

-

-      if (colour_type == 3) /* palette */

-         init_standard_palette(ps, pp, pi, 1U << bit_depth, 1/*do tRNS*/);

-

-      png_write_info(pp, pi);

-

-      if (png_get_rowbytes(pp, pi) !=

-          transform_rowsize(pp, colour_type, bit_depth))

-         png_error(pp, "row size incorrect");

-

-      else

-      {

-         /* Somewhat confusingly this must be called *after* png_write_info

-          * because if it is called before, the information in *pp has not been

-          * updated to reflect the interlaced image.

-          */

-         int npasses = png_set_interlace_handling(pp);

-         int pass;

-

-         if (npasses != npasses_from_interlace_type(pp, interlace_type))

-            png_error(pp, "write: png_set_interlace_handling failed");

-

-         for (pass=0; pass<npasses; ++pass)

-         {

-            png_uint_32 y;

-

-            for (y=0; y<h; ++y)

-            {

-               png_byte buffer[TRANSFORM_ROWMAX];

-

-               transform_row(pp, buffer, colour_type, bit_depth, y);

-               png_write_row(pp, buffer);

-            }

-         }

-      }

-

-#ifdef PNG_TEXT_SUPPORTED

-      {

-         static char key[] = "end marker";

-         static char comment[] = "end";

-         png_text text;

-

-         /* Use a compressed text string to test the correct interaction of text

-          * compression and IDAT compression.

-          */

-         text.compression = PNG_TEXT_COMPRESSION_zTXt;

-         text.key = key;

-         text.text = comment;

-         text.text_length = (sizeof comment)-1;

-         text.itxt_length = 0;

-         text.lang = 0;

-         text.lang_key = 0;

-

-         png_set_text(pp, pi, &text, 1);

-      }

-#endif

-

-      png_write_end(pp, pi);

-

-      /* And store this under the appropriate id, then clean up. */

-      store_storefile(ps, FILEID(colour_type, bit_depth, palette_number,

-         interlace_type, 0, 0, 0));

-

-      store_write_reset(ps);

-   }

-

-   Catch(fault)

-   {

-      /* Use the png_store returned by the exception. This may help the compiler

-       * because 'ps' is not used in this branch of the setjmp.  Note that fault

-       * and ps will always be the same value.

-       */

-      store_write_reset(fault);

-   }

-}

-

-static void

-make_transform_images(png_store *ps)

-{

-   png_byte colour_type = 0;

-   png_byte bit_depth = 0;

-   int palette_number = 0;

-

-   /* This is in case of errors. */

-   safecat(ps->test, sizeof ps->test, 0, "make standard images");

-

-   /* Use next_format to enumerate all the combinations we test, including

-    * generating multiple low bit depth palette images.

-    */

-   while (next_format(&colour_type, &bit_depth, &palette_number))

-   {

-      int interlace_type;

-

-      for (interlace_type = PNG_INTERLACE_NONE;

-           interlace_type < PNG_INTERLACE_LAST; ++interlace_type)

-      {

-         char name[FILE_NAME_SIZE];

-

-         standard_name(name, sizeof name, 0, colour_type, bit_depth,

-            palette_number, interlace_type, 0, 0, 0);

-         make_transform_image(ps, colour_type, bit_depth, palette_number,

-            interlace_type, name);

-      }

-   }

-}

-

-/* The following two routines use the PNG interlace support macros from

- * png.h to interlace or deinterlace rows.

- */

-static void

-interlace_row(png_bytep buffer, png_const_bytep imageRow,

-   unsigned int pixel_size, png_uint_32 w, int pass)

-{

-   png_uint_32 xin, xout, xstep;

-

-   /* Note that this can, trivially, be optimized to a memcpy on pass 7, the

-    * code is presented this way to make it easier to understand.  In practice

-    * consult the code in the libpng source to see other ways of doing this.

-    */

-   xin = PNG_PASS_START_COL(pass);

-   xstep = 1U<<PNG_PASS_COL_SHIFT(pass);

-

-   for (xout=0; xin<w; xin+=xstep)

-   {

-      pixel_copy(buffer, xout, imageRow, xin, pixel_size);

-      ++xout;

-   }

-}

-

-static void

-deinterlace_row(png_bytep buffer, png_const_bytep row,

-   unsigned int pixel_size, png_uint_32 w, int pass)

-{

-   /* The inverse of the above, 'row' is part of row 'y' of the output image,

-    * in 'buffer'.  The image is 'w' wide and this is pass 'pass', distribute

-    * the pixels of row into buffer and return the number written (to allow

-    * this to be checked).

-    */

-   png_uint_32 xin, xout, xstep;

-

-   xout = PNG_PASS_START_COL(pass);

-   xstep = 1U<<PNG_PASS_COL_SHIFT(pass);

-

-   for (xin=0; xout<w; xout+=xstep)

-   {

-      pixel_copy(buffer, xout, row, xin, pixel_size);

-      ++xin;

-   }

-}

-

-/* Build a single row for the 'size' test images; this fills in only the

- * first bit_width bits of the sample row.

- */

-static void

-size_row(png_byte buffer[SIZE_ROWMAX], png_uint_32 bit_width, png_uint_32 y)

-{

-   /* height is in the range 1 to 16, so: */

-   y = ((y & 1) << 7) + ((y & 2) << 6) + ((y & 4) << 5) + ((y & 8) << 4);

-   /* the following ensures bits are set in small images: */

-   y ^= 0xA5;

-

-   while (bit_width >= 8)

-      *buffer++ = (png_byte)y++, bit_width -= 8;

-

-   /* There may be up to 7 remaining bits, these go in the most significant

-    * bits of the byte.

-    */

-   if (bit_width > 0)

-   {

-      png_uint_32 mask = (1U<<(8-bit_width))-1;

-      *buffer = (png_byte)((*buffer & mask) | (y & ~mask));

-   }

-}

-

-static void

-make_size_image(png_store* PNG_CONST ps, png_byte PNG_CONST colour_type,

-    png_byte PNG_CONST bit_depth, int PNG_CONST interlace_type,

-    png_uint_32 PNG_CONST w, png_uint_32 PNG_CONST h,

-    int PNG_CONST do_interlace)

-{

-   context(ps, fault);

-

-   Try

-   {

-      png_infop pi;

-      png_structp pp;

-      unsigned int pixel_size;

-

-      /* Make a name and get an appropriate id for the store: */

-      char name[FILE_NAME_SIZE];

-      PNG_CONST png_uint_32 id = FILEID(colour_type, bit_depth, 0/*palette*/,

-         interlace_type, w, h, do_interlace);

-

-      standard_name_from_id(name, sizeof name, 0, id);

-      pp = set_store_for_write(ps, &pi, name);

-

-      /* In the event of a problem return control to the Catch statement below

-       * to do the clean up - it is not possible to 'return' directly from a Try

-       * block.

-       */

-      if (pp == NULL)

-         Throw ps;

-

-      png_set_IHDR(pp, pi, w, h, bit_depth, colour_type, interlace_type,

-         PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);

-

-      if (colour_type == 3) /* palette */

-         init_standard_palette(ps, pp, pi, 1U << bit_depth, 0/*do tRNS*/);

-

-      png_write_info(pp, pi);

-

-      /* Calculate the bit size, divide by 8 to get the byte size - this won't

-       * overflow because we know the w values are all small enough even for

-       * a system where 'unsigned int' is only 16 bits.

-       */

-      pixel_size = bit_size(pp, colour_type, bit_depth);

-      if (png_get_rowbytes(pp, pi) != ((w * pixel_size) + 7) / 8)

-         png_error(pp, "row size incorrect");

-

-      else

-      {

-         int npasses = npasses_from_interlace_type(pp, interlace_type);

-         png_uint_32 y;

-         int pass;

-         png_byte image[16][SIZE_ROWMAX];

-

-         /* To help consistent error detection make the parts of this buffer

-          * that aren't set below all '1':

-          */

-         memset(image, 0xff, sizeof image);

-

-         if (!do_interlace && npasses != png_set_interlace_handling(pp))

-            png_error(pp, "write: png_set_interlace_handling failed");

-

-         /* Prepare the whole image first to avoid making it 7 times: */

-         for (y=0; y<h; ++y)

-            size_row(image[y], w * pixel_size, y);

-

-         for (pass=0; pass<npasses; ++pass)

-         {

-            /* The following two are for checking the macros: */

-            PNG_CONST png_uint_32 wPass = PNG_PASS_COLS(w, pass);

-

-            /* If do_interlace is set we don't call png_write_row for every

-             * row because some of them are empty.  In fact, for a 1x1 image,

-             * most of them are empty!

-             */

-            for (y=0; y<h; ++y)

-            {

-               png_const_bytep row = image[y];

-               png_byte tempRow[SIZE_ROWMAX];

-

-               /* If do_interlace *and* the image is interlaced we

-                * need a reduced interlace row; this may be reduced

-                * to empty.

-                */

-               if (do_interlace && interlace_type == PNG_INTERLACE_ADAM7)

-               {

-                  /* The row must not be written if it doesn't exist, notice

-                   * that there are two conditions here, either the row isn't

-                   * ever in the pass or the row would be but isn't wide

-                   * enough to contribute any pixels.  In fact the wPass test

-                   * can be used to skip the whole y loop in this case.

-                   */

-                  if (PNG_ROW_IN_INTERLACE_PASS(y, pass) && wPass > 0)

-                  {

-                     /* Set to all 1's for error detection (libpng tends to

-                      * set unset things to 0).

-                      */

-                     memset(tempRow, 0xff, sizeof tempRow);

-                     interlace_row(tempRow, row, pixel_size, w, pass);

-                     row = tempRow;

-                  }

-                  else

-                     continue;

-               }

-

-               /* Only get to here if the row has some pixels in it. */

-               png_write_row(pp, row);

-            }

-         }

-      }

-

-      png_write_end(pp, pi);

-

-      /* And store this under the appropriate id, then clean up. */

-      store_storefile(ps, id);

-

-      store_write_reset(ps);

-   }

-

-   Catch(fault)

-   {

-      /* Use the png_store returned by the exception. This may help the compiler

-       * because 'ps' is not used in this branch of the setjmp.  Note that fault

-       * and ps will always be the same value.

-       */

-      store_write_reset(fault);

-   }

-}

-

-static void

-make_size(png_store* PNG_CONST ps, png_byte PNG_CONST colour_type, int bdlo,

-    int PNG_CONST bdhi)

-{

-   for (; bdlo <= bdhi; ++bdlo)

-   {

-      png_uint_32 width;

-

-      for (width = 1; width <= 16; ++width)

-      {

-         png_uint_32 height;

-

-         for (height = 1; height <= 16; ++height)

-         {

-            /* The four combinations of DIY interlace and interlace or not -

-             * no interlace + DIY should be identical to no interlace with

-             * libpng doing it.

-             */

-            make_size_image(ps, colour_type, DEPTH(bdlo), PNG_INTERLACE_NONE,

-               width, height, 0);

-            make_size_image(ps, colour_type, DEPTH(bdlo), PNG_INTERLACE_NONE,

-               width, height, 1);

-            make_size_image(ps, colour_type, DEPTH(bdlo), PNG_INTERLACE_ADAM7,

-               width, height, 0);

-            make_size_image(ps, colour_type, DEPTH(bdlo), PNG_INTERLACE_ADAM7,

-               width, height, 1);

-         }

-      }

-   }

-}

-

-static void

-make_size_images(png_store *ps)

-{

-   /* This is in case of errors. */

-   safecat(ps->test, sizeof ps->test, 0, "make size images");

-

-   /* Arguments are colour_type, low bit depth, high bit depth

-    */

-   make_size(ps, 0, 0, WRITE_BDHI);

-   make_size(ps, 2, 3, WRITE_BDHI);

-   make_size(ps, 3, 0, 3 /*palette: max 8 bits*/);

-   make_size(ps, 4, 3, WRITE_BDHI);

-   make_size(ps, 6, 3, WRITE_BDHI);

-}

-

-/* Return a row based on image id and 'y' for checking: */

-static void

-standard_row(png_structp pp, png_byte std[STANDARD_ROWMAX], png_uint_32 id,

-   png_uint_32 y)

-{

-   if (WIDTH_FROM_ID(id) == 0)

-      transform_row(pp, std, COL_FROM_ID(id), DEPTH_FROM_ID(id), y);

-   else

-      size_row(std, WIDTH_FROM_ID(id) * bit_size(pp, COL_FROM_ID(id),

-         DEPTH_FROM_ID(id)), y);

-}

-

-/* Tests - individual test cases */

-/* Like 'make_standard' but errors are deliberately introduced into the calls

- * to ensure that they get detected - it should not be possible to write an

- * invalid image with libpng!

- */

-#ifdef PNG_WARNINGS_SUPPORTED

-static void

-sBIT0_error_fn(png_structp pp, png_infop pi)

-{

-   /* 0 is invalid... */

-   png_color_8 bad;

-   bad.red = bad.green = bad.blue = bad.gray = bad.alpha = 0;

-   png_set_sBIT(pp, pi, &bad);

-}

-

-static void

-sBIT_error_fn(png_structp pp, png_infop pi)

-{

-   png_byte bit_depth;

-   png_color_8 bad;

-

-   if (png_get_color_type(pp, pi) == PNG_COLOR_TYPE_PALETTE)

-      bit_depth = 8;

-

-   else

-      bit_depth = png_get_bit_depth(pp, pi);

-

-   /* Now we know the bit depth we can easily generate an invalid sBIT entry */

-   bad.red = bad.green = bad.blue = bad.gray = bad.alpha =

-      (png_byte)(bit_depth+1);

-   png_set_sBIT(pp, pi, &bad);

-}

-

-static PNG_CONST struct

-{

-   void          (*fn)(png_structp, png_infop);

-   PNG_CONST char *msg;

-   unsigned int    warning :1; /* the error is a warning... */

-} error_test[] =

-    {

-       /* no warnings makes these errors undetectable. */

-       { sBIT0_error_fn, "sBIT(0): failed to detect error", 1 },

-       { sBIT_error_fn, "sBIT(too big): failed to detect error", 1 },

-    };

-

-static void

-make_error(png_store* volatile psIn, png_byte PNG_CONST colour_type,

-    png_byte bit_depth, int interlace_type, int test, png_const_charp name)

-{

-   png_store * volatile ps = psIn;

-

-   context(ps, fault);

-

-   Try

-   {

-      png_structp pp;

-      png_infop pi;

-

-      pp = set_store_for_write(ps, &pi, name);

-

-      if (pp == NULL)

-         Throw ps;

-

-      png_set_IHDR(pp, pi, transform_width(pp, colour_type, bit_depth),

-         transform_height(pp, colour_type, bit_depth), bit_depth, colour_type,

-         interlace_type, PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);

-

-      if (colour_type == 3) /* palette */

-         init_standard_palette(ps, pp, pi, 1U << bit_depth, 0/*do tRNS*/);

-

-      /* Time for a few errors; these are in various optional chunks, the

-       * standard tests test the standard chunks pretty well.

-       */

-#     define exception__prev exception_prev_1

-#     define exception__env exception_env_1

-      Try

-      {

-         /* Expect this to throw: */

-         ps->expect_error = !error_test[test].warning;

-         ps->expect_warning = error_test[test].warning;

-         ps->saw_warning = 0;

-         error_test[test].fn(pp, pi);

-

-         /* Normally the error is only detected here: */

-         png_write_info(pp, pi);

-

-         /* And handle the case where it was only a warning: */

-         if (ps->expect_warning && ps->saw_warning)

-            Throw ps;

-

-         /* If we get here there is a problem, we have success - no error or

-          * no warning - when we shouldn't have success.  Log an error.

-          */

-         store_log(ps, pp, error_test[test].msg, 1 /*error*/);

-      }

-

-      Catch (fault)

-         ps = fault; /* expected exit, make sure ps is not clobbered */

-#undef exception__prev

-#undef exception__env

-

-      /* And clear these flags */

-      ps->expect_error = 0;

-      ps->expect_warning = 0;

-

-      /* Now write the whole image, just to make sure that the detected, or

-       * undetected, errro has not created problems inside libpng.

-       */

-      if (png_get_rowbytes(pp, pi) !=

-          transform_rowsize(pp, colour_type, bit_depth))

-         png_error(pp, "row size incorrect");

-

-      else

-      {

-         png_uint_32 h = transform_height(pp, colour_type, bit_depth);

-         int npasses = png_set_interlace_handling(pp);

-         int pass;

-

-         if (npasses != npasses_from_interlace_type(pp, interlace_type))

-            png_error(pp, "write: png_set_interlace_handling failed");

-

-         for (pass=0; pass<npasses; ++pass)

-         {

-            png_uint_32 y;

-

-            for (y=0; y<h; ++y)

-            {

-               png_byte buffer[TRANSFORM_ROWMAX];

-

-               transform_row(pp, buffer, colour_type, bit_depth, y);

-               png_write_row(pp, buffer);

-            }

-         }

-      }

-

-      png_write_end(pp, pi);

-

-      /* The following deletes the file that was just written. */

-      store_write_reset(ps);

-   }

-

-   Catch(fault)

-   {

-      store_write_reset(fault);

-   }

-}

-

-static int

-make_errors(png_modifier* PNG_CONST pm, png_byte PNG_CONST colour_type,

-    int bdlo, int PNG_CONST bdhi)

-{

-   for (; bdlo <= bdhi; ++bdlo)

-   {

-      int interlace_type;

-

-      for (interlace_type = PNG_INTERLACE_NONE;

-           interlace_type < PNG_INTERLACE_LAST; ++interlace_type)

-      {

-         unsigned int test;

-         char name[FILE_NAME_SIZE];

-

-         standard_name(name, sizeof name, 0, colour_type, 1<<bdlo, 0,

-            interlace_type, 0, 0, 0);

-

-         for (test=0; test<(sizeof error_test)/(sizeof error_test[0]); ++test)

-         {

-            make_error(&pm->this, colour_type, DEPTH(bdlo), interlace_type,

-               test, name);

-

-            if (fail(pm))

-               return 0;

-         }

-      }

-   }

-

-   return 1; /* keep going */

-}

-#endif

-

-static void

-perform_error_test(png_modifier *pm)

-{

-#ifdef PNG_WARNINGS_SUPPORTED /* else there are no cases that work! */

-   /* Need to do this here because we just write in this test. */

-   safecat(pm->this.test, sizeof pm->this.test, 0, "error test");

-

-   if (!make_errors(pm, 0, 0, WRITE_BDHI))

-      return;

-

-   if (!make_errors(pm, 2, 3, WRITE_BDHI))

-      return;

-

-   if (!make_errors(pm, 3, 0, 3))

-      return;

-

-   if (!make_errors(pm, 4, 3, WRITE_BDHI))

-      return;

-

-   if (!make_errors(pm, 6, 3, WRITE_BDHI))

-      return;

-#else

-   UNUSED(pm)

-#endif

-}

-

-/* This is just to validate the internal PNG formatting code - if this fails

- * then the warning messages the library outputs will probably be garbage.

- */

-static void

-perform_formatting_test(png_store *volatile ps)

-{

-#ifdef PNG_TIME_RFC1123_SUPPORTED

-   /* The handle into the formatting code is the RFC1123 support; this test does

-    * nothing if that is compiled out.

-    */

-   context(ps, fault);

-

-   Try

-   {

-      png_const_charp correct = "29 Aug 2079 13:53:60 +0000";

-      png_const_charp result;

-      png_structp pp;

-      png_time pt;

-

-      pp = set_store_for_write(ps, NULL, "libpng formatting test");

-

-      if (pp == NULL)

-         Throw ps;

-

-

-      /* Arbitrary settings: */

-      pt.year = 2079;

-      pt.month = 8;

-      pt.day = 29;

-      pt.hour = 13;

-      pt.minute = 53;

-      pt.second = 60; /* a leap second */

-

-      result = png_convert_to_rfc1123(pp, &pt);

-

-      if (result == NULL)

-         png_error(pp, "png_convert_to_rfc1123 failed");

-

-      if (strcmp(result, correct) != 0)

-      {

-         size_t pos = 0;

-         char msg[128];

-

-         pos = safecat(msg, sizeof msg, pos, "png_convert_to_rfc1123(");

-         pos = safecat(msg, sizeof msg, pos, correct);

-         pos = safecat(msg, sizeof msg, pos, ") returned: '");

-         pos = safecat(msg, sizeof msg, pos, result);

-         pos = safecat(msg, sizeof msg, pos, "'");

-

-         png_error(pp, msg);

-      }

-

-      store_write_reset(ps);

-   }

-

-   Catch(fault)

-   {

-      store_write_reset(fault);

-   }

-#else

-   UNUSED(ps)

-#endif

-}

-

-/* Because we want to use the same code in both the progressive reader and the

- * sequential reader it is necessary to deal with the fact that the progressive

- * reader callbacks only have one parameter (png_get_progressive_ptr()), so this

- * must contain all the test parameters and all the local variables directly

- * accessible to the sequential reader implementation.

- *

- * The technique adopted is to reinvent part of what Dijkstra termed a

- * 'display'; an array of pointers to the stack frames of enclosing functions so

- * that a nested function definition can access the local (C auto) variables of

- * the functions that contain its definition.  In fact C provides the first

- * pointer (the local variables - the stack frame pointer) and the last (the

- * global variables - the BCPL global vector typically implemented as global

- * addresses), this code requires one more pointer to make the display - the

- * local variables (and function call parameters) of the function that actually

- * invokes either the progressive or sequential reader.

- *

- * Perhaps confusingly this technique is confounded with classes - the

- * 'standard_display' defined here is sub-classed as the 'gamma_display' below.

- * A gamma_display is a standard_display, taking advantage of the ANSI-C

- * requirement that the pointer to the first member of a structure must be the

- * same as the pointer to the structure.  This allows us to reuse standard_

- * functions in the gamma test code; something that could not be done with

- * nested functions!

- */

-typedef struct standard_display

-{

-   png_store*  ps;             /* Test parameters (passed to the function) */

-   png_byte    colour_type;

-   png_byte    bit_depth;

-   png_byte    red_sBIT;       /* Input data sBIT values. */

-   png_byte    green_sBIT;

-   png_byte    blue_sBIT;

-   png_byte    alpha_sBIT;

-   int         interlace_type;

-   png_uint_32 id;             /* Calculated file ID */

-   png_uint_32 w;              /* Width of image */

-   png_uint_32 h;              /* Height of image */

-   int         npasses;        /* Number of interlaced passes */

-   png_uint_32 pixel_size;     /* Width of one pixel in bits */

-   png_uint_32 bit_width;      /* Width of output row in bits */

-   size_t      cbRow;          /* Bytes in a row of the output image */

-   int         do_interlace;   /* Do interlacing internally */

-   int         is_transparent; /* Transparency information was present. */

-   int         speed;          /* Doing a speed test */

-   int         use_update_info;/* Call update_info, not start_image */

-   struct

-   {

-      png_uint_16 red;

-      png_uint_16 green;

-      png_uint_16 blue;

-   }           transparent;    /* The transparent color, if set. */

-   int         npalette;       /* Number of entries in the palette. */

-   store_palette

-               palette;

-} standard_display;

-

-static void

-standard_display_init(standard_display *dp, png_store* ps, png_uint_32 id,

-   int do_interlace, int use_update_info)

-{

-   memset(dp, 0, sizeof *dp);

-

-   dp->ps = ps;

-   dp->colour_type = COL_FROM_ID(id);

-   dp->bit_depth = DEPTH_FROM_ID(id);

-   if (dp->bit_depth < 1 || dp->bit_depth > 16)

-      internal_error(ps, "internal: bad bit depth");

-   if (dp->colour_type == 3)

-      dp->red_sBIT = dp->blue_sBIT = dp->green_sBIT = dp->alpha_sBIT = 8;

-   else

-      dp->red_sBIT = dp->blue_sBIT = dp->green_sBIT = dp->alpha_sBIT =

-         dp->bit_depth;

-   dp->interlace_type = INTERLACE_FROM_ID(id);

-   dp->id = id;

-   /* All the rest are filled in after the read_info: */

-   dp->w = 0;

-   dp->h = 0;

-   dp->npasses = 0;

-   dp->pixel_size = 0;

-   dp->bit_width = 0;

-   dp->cbRow = 0;

-   dp->do_interlace = do_interlace;

-   dp->is_transparent = 0;

-   dp->speed = ps->speed;

-   dp->use_update_info = use_update_info;

-   dp->npalette = 0;

-   /* Preset the transparent color to black: */

-   memset(&dp->transparent, 0, sizeof dp->transparent);

-   /* Preset the palette to full intensity/opaque througout: */

-   memset(dp->palette, 0xff, sizeof dp->palette);

-}

-

-/* Initialize the palette fields - this must be done later because the palette

- * comes from the particular png_store_file that is selected.

- */

-static void

-standard_palette_init(standard_display *dp)

-{

-   store_palette_entry *palette = store_current_palette(dp->ps, &dp->npalette);

-

-   /* The remaining entries remain white/opaque. */

-   if (dp->npalette > 0)

-   {

-      int i = dp->npalette;

-      memcpy(dp->palette, palette, i * sizeof *palette);

-

-      /* Check for a non-opaque palette entry: */

-      while (--i >= 0)

-         if (palette[i].alpha < 255)

-            break;

-

-#     ifdef __GNUC__

-         /* GCC can't handle the more obviously optimizable version. */

-         if (i >= 0)

-            dp->is_transparent = 1;

-         else

-            dp->is_transparent = 0;

-#     else

-         dp->is_transparent = (i >= 0);

-#     endif

-   }

-}

-

-/* Utility to read the palette from the PNG file and convert it into

- * store_palette format.  This returns 1 if there is any transparency in the

- * palette (it does not check for a transparent colour in the non-palette case.)

- */

-static int

-read_palette(store_palette palette, int *npalette, png_structp pp, png_infop pi)

-{

-   png_colorp pal;

-   png_bytep trans_alpha;

-   int num;

-

-   pal = 0;

-   *npalette = -1;

-

-   if (png_get_PLTE(pp, pi, &pal, npalette) & PNG_INFO_PLTE)

-   {

-      int i = *npalette;

-

-      if (i <= 0 || i > 256)

-         png_error(pp, "validate: invalid PLTE count");

-

-      while (--i >= 0)

-      {

-         palette[i].red = pal[i].red;

-         palette[i].green = pal[i].green;

-         palette[i].blue = pal[i].blue;

-      }

-

-      /* Mark the remainder of the entries with a flag value (other than

-       * white/opaque which is the flag value stored above.)

-       */

-      memset(palette + *npalette, 126, (256-*npalette) * sizeof *palette);

-   }

-

-   else /* !png_get_PLTE */

-   {

-      if (*npalette != (-1))

-         png_error(pp, "validate: invalid PLTE result");

-      /* But there is no palette, so record this: */

-      *npalette = 0;

-      memset(palette, 113, sizeof (store_palette));

-   }

-

-   trans_alpha = 0;

-   num = 2; /* force error below */

-   if ((png_get_tRNS(pp, pi, &trans_alpha, &num, 0) & PNG_INFO_tRNS) != 0 &&

-      (trans_alpha != NULL || num != 1/*returns 1 for a transparent color*/) &&

-      /* Oops, if a palette tRNS gets expanded png_read_update_info (at least so

-       * far as 1.5.4) does not remove the trans_alpha pointer, only num_trans,

-       * so in the above call we get a success, we get a pointer (who knows what

-       * to) and we get num_trans == 0:

-       */

-      !(trans_alpha != NULL && num == 0)) /* TODO: fix this in libpng. */

-   {

-      int i;

-

-      /* Any of these are crash-worthy - given the implementation of

-       * png_get_tRNS up to 1.5 an app won't crash if it just checks the

-       * result above and fails to check that the variables it passed have

-       * actually been filled in!  Note that if the app were to pass the

-       * last, png_color_16p, variable too it couldn't rely on this.

-       */

-      if (trans_alpha == NULL || num <= 0 || num > 256 || num > *npalette)

-         png_error(pp, "validate: unexpected png_get_tRNS (palette) result");

-

-      for (i=0; i<num; ++i)

-         palette[i].alpha = trans_alpha[i];

-

-      for (num=*npalette; i<num; ++i)

-         palette[i].alpha = 255;

-

-      for (; i<256; ++i)

-         palette[i].alpha = 33; /* flag value */

-

-      return 1; /* transparency */

-   }

-

-   else

-   {

-      /* No palette transparency - just set the alpha channel to opaque. */

-      int i;

-

-      for (i=0, num=*npalette; i<num; ++i)

-         palette[i].alpha = 255;

-

-      for (; i<256; ++i)

-         palette[i].alpha = 55; /* flag value */

-

-      return 0; /* no transparency */

-   }

-}

-

-/* Utility to validate the palette if it should not have changed (the

- * non-transform case).

- */

-static void

-standard_palette_validate(standard_display *dp, png_structp pp, png_infop pi)

-{

-   int npalette;

-   store_palette palette;

-

-   if (read_palette(palette, &npalette, pp, pi) != dp->is_transparent)

-      png_error(pp, "validate: palette transparency changed");

-

-   if (npalette != dp->npalette)

-   {

-      size_t pos = 0;

-      char msg[64];

-

-      pos = safecat(msg, sizeof msg, pos, "validate: palette size changed: ");

-      pos = safecatn(msg, sizeof msg, pos, dp->npalette);

-      pos = safecat(msg, sizeof msg, pos, " -> ");

-      pos = safecatn(msg, sizeof msg, pos, npalette);

-      png_error(pp, msg);

-   }

-

-   {

-      int i = npalette; /* npalette is aliased */

-

-      while (--i >= 0)

-         if (palette[i].red != dp->palette[i].red ||

-            palette[i].green != dp->palette[i].green ||

-            palette[i].blue != dp->palette[i].blue ||

-            palette[i].alpha != dp->palette[i].alpha)

-            png_error(pp, "validate: PLTE or tRNS chunk changed");

-   }

-}

-

-/* By passing a 'standard_display' the progressive callbacks can be used

- * directly by the sequential code, the functions suffixed "_imp" are the

- * implementations, the functions without the suffix are the callbacks.

- *

- * The code for the info callback is split into two because this callback calls

- * png_read_update_info or png_start_read_image and what gets called depends on

- * whether the info needs updating (we want to test both calls in pngvalid.)

- */

-static void

-standard_info_part1(standard_display *dp, png_structp pp, png_infop pi)

-{

-   if (png_get_bit_depth(pp, pi) != dp->bit_depth)

-      png_error(pp, "validate: bit depth changed");

-

-   if (png_get_color_type(pp, pi) != dp->colour_type)

-      png_error(pp, "validate: color type changed");

-

-   if (png_get_filter_type(pp, pi) != PNG_FILTER_TYPE_BASE)

-      png_error(pp, "validate: filter type changed");

-

-   if (png_get_interlace_type(pp, pi) != dp->interlace_type)

-      png_error(pp, "validate: interlacing changed");

-

-   if (png_get_compression_type(pp, pi) != PNG_COMPRESSION_TYPE_BASE)

-      png_error(pp, "validate: compression type changed");

-

-   dp->w = png_get_image_width(pp, pi);

-

-   if (dp->w != standard_width(pp, dp->id))

-      png_error(pp, "validate: image width changed");

-

-   dp->h = png_get_image_height(pp, pi);

-

-   if (dp->h != standard_height(pp, dp->id))

-      png_error(pp, "validate: image height changed");

-

-   /* Record (but don't check at present) the input sBIT according to the colour

-    * type information.

-    */

-   {

-      png_color_8p sBIT = 0;

-

-      if (png_get_sBIT(pp, pi, &sBIT) & PNG_INFO_sBIT)

-      {

-         int sBIT_invalid = 0;

-

-         if (sBIT == 0)

-            png_error(pp, "validate: unexpected png_get_sBIT result");

-

-         if (dp->colour_type & PNG_COLOR_MASK_COLOR)

-         {

-            if (sBIT->red == 0 || sBIT->red > dp->bit_depth)

-               sBIT_invalid = 1;

-            else

-               dp->red_sBIT = sBIT->red;

-

-            if (sBIT->green == 0 || sBIT->green > dp->bit_depth)

-               sBIT_invalid = 1;

-            else

-               dp->green_sBIT = sBIT->green;

-

-            if (sBIT->blue == 0 || sBIT->blue > dp->bit_depth)

-               sBIT_invalid = 1;

-            else

-               dp->blue_sBIT = sBIT->blue;

-         }

-

-         else /* !COLOR */

-         {

-            if (sBIT->gray == 0 || sBIT->gray > dp->bit_depth)

-               sBIT_invalid = 1;

-            else

-               dp->blue_sBIT = dp->green_sBIT = dp->red_sBIT = sBIT->gray;

-         }

-

-         /* All 8 bits in tRNS for a palette image are significant - see the

-          * spec.

-          */

-         if (dp->colour_type & PNG_COLOR_MASK_ALPHA)

-         {

-            if (sBIT->alpha == 0 || sBIT->alpha > dp->bit_depth)

-               sBIT_invalid = 1;

-            else

-               dp->alpha_sBIT = sBIT->alpha;

-         }

-

-         if (sBIT_invalid)

-            png_error(pp, "validate: sBIT value out of range");

-      }

-   }

-

-   /* Important: this is validating the value *before* any transforms have been

-    * put in place.  It doesn't matter for the standard tests, where there are

-    * no transforms, but it does for other tests where rowbytes may change after

-    * png_read_update_info.

-    */

-   if (png_get_rowbytes(pp, pi) != standard_rowsize(pp, dp->id))

-      png_error(pp, "validate: row size changed");

-

-   /* Validate the colour type 3 palette (this can be present on other color

-    * types.)

-    */

-   standard_palette_validate(dp, pp, pi);

-

-   /* In any case always check for a tranparent color (notice that the

-    * colour type 3 case must not give a successful return on the get_tRNS call

-    * with these arguments!)

-    */

-   {

-      png_color_16p trans_color = 0;

-

-      if (png_get_tRNS(pp, pi, 0, 0, &trans_color) & PNG_INFO_tRNS)

-      {

-         if (trans_color == 0)

-            png_error(pp, "validate: unexpected png_get_tRNS (color) result");

-

-         switch (dp->colour_type)

-         {

-         case 0:

-            dp->transparent.red = dp->transparent.green = dp->transparent.blue =

-               trans_color->gray;

-            dp->is_transparent = 1;

-            break;

-

-         case 2:

-            dp->transparent.red = trans_color->red;

-            dp->transparent.green = trans_color->green;

-            dp->transparent.blue = trans_color->blue;

-            dp->is_transparent = 1;

-            break;

-

-         case 3:

-            /* Not expected because it should result in the array case

-             * above.

-             */

-            png_error(pp, "validate: unexpected png_get_tRNS result");

-            break;

-

-         default:

-            png_error(pp, "validate: invalid tRNS chunk with alpha image");

-         }

-      }

-   }

-

-   /* Read the number of passes - expected to match the value used when

-    * creating the image (interlaced or not).  This has the side effect of

-    * turning on interlace handling (if do_interlace is not set.)

-    */

-   dp->npasses = npasses_from_interlace_type(pp, dp->interlace_type);

-   if (!dp->do_interlace && dp->npasses != png_set_interlace_handling(pp))

-      png_error(pp, "validate: file changed interlace type");

-

-   /* Caller calls png_read_update_info or png_start_read_image now, then calls

-    * part2.

-    */

-}

-

-/* This must be called *after* the png_read_update_info call to get the correct

- * 'rowbytes' value, otherwise png_get_rowbytes will refer to the untransformed

- * image.

- */

-static void

-standard_info_part2(standard_display *dp, png_structp pp, png_infop pi,

-    int nImages)

-{

-   /* Record cbRow now that it can be found. */

-   dp->pixel_size = bit_size(pp, png_get_color_type(pp, pi),

-      png_get_bit_depth(pp, pi));

-   dp->bit_width = png_get_image_width(pp, pi) * dp->pixel_size;

-   dp->cbRow = png_get_rowbytes(pp, pi);

-

-   /* Validate the rowbytes here again. */

-   if (dp->cbRow != (dp->bit_width+7)/8)

-      png_error(pp, "bad png_get_rowbytes calculation");

-

-   /* Then ensure there is enough space for the output image(s). */

-   store_ensure_image(dp->ps, pp, nImages, dp->cbRow, dp->h);

-}

-

-static void

-standard_info_imp(standard_display *dp, png_structp pp, png_infop pi,

-    int nImages)

-{

-   /* Note that the validation routine has the side effect of turning on

-    * interlace handling in the subsequent code.

-    */

-   standard_info_part1(dp, pp, pi);

-

-   /* And the info callback has to call this (or png_read_update_info - see

-    * below in the png_modifier code for that variant.

-    */

-   if (dp->use_update_info)

-   {

-      /* For debugging the effect of multiple calls: */

-      int i = dp->use_update_info;

-      while (i-- > 0)

-         png_read_update_info(pp, pi);

-   }

-

-   else

-      png_start_read_image(pp);

-

-   /* Validate the height, width and rowbytes plus ensure that sufficient buffer

-    * exists for decoding the image.

-    */

-   standard_info_part2(dp, pp, pi, nImages);

-}

-

-static void

-standard_info(png_structp pp, png_infop pi)

-{

-   standard_display *dp = voidcast(standard_display*,

-      png_get_progressive_ptr(pp));

-

-   /* Call with nImages==1 because the progressive reader can only produce one

-    * image.

-    */

-   standard_info_imp(dp, pp, pi, 1 /*only one image*/);

-}

-

-static void

-progressive_row(png_structp pp, png_bytep new_row, png_uint_32 y, int pass)

-{

-   PNG_CONST standard_display *dp = voidcast(standard_display*,

-      png_get_progressive_ptr(pp));

-

-   /* When handling interlacing some rows will be absent in each pass, the

-    * callback still gets called, but with a NULL pointer.  This is checked

-    * in the 'else' clause below.  We need our own 'cbRow', but we can't call

-    * png_get_rowbytes because we got no info structure.

-    */

-   if (new_row != NULL)

-   {

-      png_bytep row;

-

-      /* In the case where the reader doesn't do the interlace it gives

-       * us the y in the sub-image:

-       */

-      if (dp->do_interlace && dp->interlace_type == PNG_INTERLACE_ADAM7)

-      {

-#ifdef PNG_USER_TRANSFORM_INFO_SUPPORTED

-         /* Use this opportunity to validate the png 'current' APIs: */

-         if (y != png_get_current_row_number(pp))

-            png_error(pp, "png_get_current_row_number is broken");

-

-         if (pass != png_get_current_pass_number(pp))

-            png_error(pp, "png_get_current_pass_number is broken");

-#endif

-

-         y = PNG_ROW_FROM_PASS_ROW(y, pass);

-      }

-

-      /* Validate this just in case. */

-      if (y >= dp->h)

-         png_error(pp, "invalid y to progressive row callback");

-

-      row = store_image_row(dp->ps, pp, 0, y);

-

-#ifdef PNG_READ_INTERLACING_SUPPORTED

-      /* Combine the new row into the old: */

-      if (dp->do_interlace)

-      {

-         if (dp->interlace_type == PNG_INTERLACE_ADAM7)

-            deinterlace_row(row, new_row, dp->pixel_size, dp->w, pass);

-         else

-            row_copy(row, new_row, dp->pixel_size * dp->w);

-      }

-      else

-         png_progressive_combine_row(pp, row, new_row);

-   } else if (dp->interlace_type == PNG_INTERLACE_ADAM7 &&

-      PNG_ROW_IN_INTERLACE_PASS(y, pass) &&

-      PNG_PASS_COLS(dp->w, pass) > 0)

-      png_error(pp, "missing row in progressive de-interlacing");

-#endif /* PNG_READ_INTERLACING_SUPPORTED */

-}

-

-static void

-sequential_row(standard_display *dp, png_structp pp, png_infop pi,

-    PNG_CONST int iImage, PNG_CONST int iDisplay)

-{

-   PNG_CONST int         npasses = dp->npasses;

-   PNG_CONST int         do_interlace = dp->do_interlace &&

-      dp->interlace_type == PNG_INTERLACE_ADAM7;

-   PNG_CONST png_uint_32 height = standard_height(pp, dp->id);

-   PNG_CONST png_uint_32 width = standard_width(pp, dp->id);

-   PNG_CONST png_store*  ps = dp->ps;

-   int pass;

-

-   for (pass=0; pass<npasses; ++pass)

-   {

-      png_uint_32 y;

-      png_uint_32 wPass = PNG_PASS_COLS(width, pass);

-

-      for (y=0; y<height; ++y)

-      {

-         if (do_interlace)

-         {

-            /* wPass may be zero or this row may not be in this pass.

-             * png_read_row must not be called in either case.

-             */

-            if (wPass > 0 && PNG_ROW_IN_INTERLACE_PASS(y, pass))

-            {

-               /* Read the row into a pair of temporary buffers, then do the

-                * merge here into the output rows.

-                */

-               png_byte row[STANDARD_ROWMAX], display[STANDARD_ROWMAX];

-

-               /* The following aids (to some extent) error detection - we can

-                * see where png_read_row wrote.  Use opposite values in row and

-                * display to make this easier.  Don't use 0xff (which is used in

-                * the image write code to fill unused bits) or 0 (which is a

-                * likely value to overwrite unused bits with).

-                */

-               memset(row, 0xc5, sizeof row);

-               memset(display, 0x5c, sizeof display);

-

-               png_read_row(pp, row, display);

-

-               if (iImage >= 0)

-                  deinterlace_row(store_image_row(ps, pp, iImage, y), row,

-                     dp->pixel_size, dp->w, pass);

-

-               if (iDisplay >= 0)

-                  deinterlace_row(store_image_row(ps, pp, iDisplay, y), display,

-                     dp->pixel_size, dp->w, pass);

-            }

-         }

-         else

-            png_read_row(pp,

-               iImage >= 0 ? store_image_row(ps, pp, iImage, y) : NULL,

-               iDisplay >= 0 ? store_image_row(ps, pp, iDisplay, y) : NULL);

-      }

-   }

-

-   /* And finish the read operation (only really necessary if the caller wants

-    * to find additional data in png_info from chunks after the last IDAT.)

-    */

-   png_read_end(pp, pi);

-}

-

-static void

-standard_row_validate(standard_display *dp, png_structp pp,

-   int iImage, int iDisplay, png_uint_32 y)

-{

-   int where;

-   png_byte std[STANDARD_ROWMAX];

-

-   /* The row must be pre-initialized to the magic number here for the size

-    * tests to pass:

-    */

-   memset(std, 178, sizeof std);

-   standard_row(pp, std, dp->id, y);

-

-   /* At the end both the 'row' and 'display' arrays should end up identical.

-    * In earlier passes 'row' will be partially filled in, with only the pixels

-    * that have been read so far, but 'display' will have those pixels

-    * replicated to fill the unread pixels while reading an interlaced image.

-#if PNG_LIBPNG_VER < 10506

-    * The side effect inside the libpng sequential reader is that the 'row'

-    * array retains the correct values for unwritten pixels within the row

-    * bytes, while the 'display' array gets bits off the end of the image (in

-    * the last byte) trashed.  Unfortunately in the progressive reader the

-    * row bytes are always trashed, so we always do a pixel_cmp here even though

-    * a memcmp of all cbRow bytes will succeed for the sequential reader.

-#endif

-    */

-   if (iImage >= 0 &&

-      (where = pixel_cmp(std, store_image_row(dp->ps, pp, iImage, y),

-            dp->bit_width)) != 0)

-   {

-      char msg[64];

-      sprintf(msg, "PNG image row[%d][%d] changed from %.2x to %.2x", y,

-         where-1, std[where-1],

-         store_image_row(dp->ps, pp, iImage, y)[where-1]);

-      png_error(pp, msg);

-   }

-

-#if PNG_LIBPNG_VER < 10506

-   /* In this case use pixel_cmp because we need to compare a partial

-    * byte at the end of the row if the row is not an exact multiple

-    * of 8 bits wide.  (This is fixed in libpng-1.5.6 and pixel_cmp is

-    * changed to match!)

-    */

-#endif

-   if (iDisplay >= 0 &&

-      (where = pixel_cmp(std, store_image_row(dp->ps, pp, iDisplay, y),

-         dp->bit_width)) != 0)

-   {

-      char msg[64];

-      sprintf(msg, "display  row[%d][%d] changed from %.2x to %.2x", y,

-         where-1, std[where-1],

-         store_image_row(dp->ps, pp, iDisplay, y)[where-1]);

-      png_error(pp, msg);

-   }

-}

-

-static void

-standard_image_validate(standard_display *dp, png_structp pp, int iImage,

-    int iDisplay)

-{

-   png_uint_32 y;

-

-   if (iImage >= 0)

-      store_image_check(dp->ps, pp, iImage);

-

-   if (iDisplay >= 0)

-      store_image_check(dp->ps, pp, iDisplay);

-

-   for (y=0; y<dp->h; ++y)

-      standard_row_validate(dp, pp, iImage, iDisplay, y);

-

-   /* This avoids false positives if the validation code is never called! */

-   dp->ps->validated = 1;

-}

-

-static void

-standard_end(png_structp pp, png_infop pi)

-{

-   standard_display *dp = voidcast(standard_display*,

-      png_get_progressive_ptr(pp));

-

-   UNUSED(pi)

-

-   /* Validate the image - progressive reading only produces one variant for

-    * interlaced images.

-    */

-   standard_image_validate(dp, pp, 0, -1);

-}

-

-/* A single test run checking the standard image to ensure it is not damaged. */

-static void

-standard_test(png_store* PNG_CONST psIn, png_uint_32 PNG_CONST id,

-   int do_interlace, int use_update_info)

-{

-   standard_display d;

-   context(psIn, fault);

-

-   /* Set up the display (stack frame) variables from the arguments to the

-    * function and initialize the locals that are filled in later.

-    */

-   standard_display_init(&d, psIn, id, do_interlace, use_update_info);

-

-   /* Everything is protected by a Try/Catch.  The functions called also

-    * typically have local Try/Catch blocks.

-    */

-   Try

-   {

-      png_structp pp;

-      png_infop pi;

-

-      /* Get a png_struct for reading the image. This will throw an error if it

-       * fails, so we don't need to check the result.

-       */

-      pp = set_store_for_read(d.ps, &pi, d.id,

-         d.do_interlace ?  (d.ps->progressive ?

-            "pngvalid progressive deinterlacer" :

-            "pngvalid sequential deinterlacer") : (d.ps->progressive ?

-               "progressive reader" : "sequential reader"));

-

-      /* Initialize the palette correctly from the png_store_file. */

-      standard_palette_init(&d);

-

-      /* Introduce the correct read function. */

-      if (d.ps->progressive)

-      {

-         png_set_progressive_read_fn(pp, &d, standard_info, progressive_row,

-            standard_end);

-

-         /* Now feed data into the reader until we reach the end: */

-         store_progressive_read(d.ps, pp, pi);

-      }

-      else

-      {

-         /* Note that this takes the store, not the display. */

-         png_set_read_fn(pp, d.ps, store_read);

-

-         /* Check the header values: */

-         png_read_info(pp, pi);

-

-         /* The code tests both versions of the images that the sequential

-          * reader can produce.

-          */

-         standard_info_imp(&d, pp, pi, 2 /*images*/);

-

-         /* Need the total bytes in the image below; we can't get to this point

-          * unless the PNG file values have been checked against the expected

-          * values.

-          */

-         {

-            sequential_row(&d, pp, pi, 0, 1);

-

-            /* After the last pass loop over the rows again to check that the

-             * image is correct.

-             */

-            if (!d.speed)

-               standard_image_validate(&d, pp, 0, 1);

-            else

-               d.ps->validated = 1;

-         }

-      }

-

-      /* Check for validation. */

-      if (!d.ps->validated)

-         png_error(pp, "image read failed silently");

-

-      /* Successful completion. */

-   }

-

-   Catch(fault)

-      d.ps = fault; /* make sure this hasn't been clobbered. */

-

-   /* In either case clean up the store. */

-   store_read_reset(d.ps);

-}

-

-static int

-test_standard(png_modifier* PNG_CONST pm, png_byte PNG_CONST colour_type,

-    int bdlo, int PNG_CONST bdhi)

-{

-   for (; bdlo <= bdhi; ++bdlo)

-   {

-      int interlace_type;

-

-      for (interlace_type = PNG_INTERLACE_NONE;

-           interlace_type < PNG_INTERLACE_LAST; ++interlace_type)

-      {

-         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,

-            interlace_type, 0, 0, 0), 0/*do_interlace*/, pm->use_update_info);

-

-         if (fail(pm))

-            return 0;

-      }

-   }

-

-   return 1; /* keep going */

-}

-

-static void

-perform_standard_test(png_modifier *pm)

-{

-   /* Test each colour type over the valid range of bit depths (expressed as

-    * log2(bit_depth) in turn, stop as soon as any error is detected.

-    */

-   if (!test_standard(pm, 0, 0, READ_BDHI))

-      return;

-

-   if (!test_standard(pm, 2, 3, READ_BDHI))

-      return;

-

-   if (!test_standard(pm, 3, 0, 3))

-      return;

-

-   if (!test_standard(pm, 4, 3, READ_BDHI))

-      return;

-

-   if (!test_standard(pm, 6, 3, READ_BDHI))

-      return;

-}

-

-

-/********************************** SIZE TESTS ********************************/

-static int

-test_size(png_modifier* PNG_CONST pm, png_byte PNG_CONST colour_type,

-    int bdlo, int PNG_CONST bdhi)

-{

-   /* Run the tests on each combination.

-    *

-    * NOTE: on my 32 bit x86 each of the following blocks takes

-    * a total of 3.5 seconds if done across every combo of bit depth

-    * width and height.  This is a waste of time in practice, hence the

-    * hinc and winc stuff:

-    */

-   static PNG_CONST png_byte hinc[] = {1, 3, 11, 1, 5};

-   static PNG_CONST png_byte winc[] = {1, 9, 5, 7, 1};

-   for (; bdlo <= bdhi; ++bdlo)

-   {

-      png_uint_32 h, w;

-

-      for (h=1; h<=16; h+=hinc[bdlo]) for (w=1; w<=16; w+=winc[bdlo])

-      {

-         /* First test all the 'size' images against the sequential

-          * reader using libpng to deinterlace (where required.)  This

-          * validates the write side of libpng.  There are four possibilities

-          * to validate.

-          */

-         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,

-            PNG_INTERLACE_NONE, w, h, 0), 0/*do_interlace*/,

-            pm->use_update_info);

-

-         if (fail(pm))

-            return 0;

-

-         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,

-            PNG_INTERLACE_NONE, w, h, 1), 0/*do_interlace*/,

-            pm->use_update_info);

-

-         if (fail(pm))

-            return 0;

-

-         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,

-            PNG_INTERLACE_ADAM7, w, h, 0), 0/*do_interlace*/,

-            pm->use_update_info);

-

-         if (fail(pm))

-            return 0;

-

-         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,

-            PNG_INTERLACE_ADAM7, w, h, 1), 0/*do_interlace*/,

-            pm->use_update_info);

-

-         if (fail(pm))

-            return 0;

-

-         /* Now validate the interlaced read side - do_interlace true,

-          * in the progressive case this does actually make a difference

-          * to the code used in the non-interlaced case too.

-          */

-         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,

-            PNG_INTERLACE_NONE, w, h, 0), 1/*do_interlace*/,

-            pm->use_update_info);

-

-         if (fail(pm))

-            return 0;

-

-         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,

-            PNG_INTERLACE_ADAM7, w, h, 0), 1/*do_interlace*/,

-            pm->use_update_info);

-

-         if (fail(pm))

-            return 0;

-      }

-   }

-

-   return 1; /* keep going */

-}

-

-static void

-perform_size_test(png_modifier *pm)

-{

-   /* Test each colour type over the valid range of bit depths (expressed as

-    * log2(bit_depth) in turn, stop as soon as any error is detected.

-    */

-   if (!test_size(pm, 0, 0, READ_BDHI))

-      return;

-

-   if (!test_size(pm, 2, 3, READ_BDHI))

-      return;

-

-   /* For the moment don't do the palette test - it's a waste of time when

-    * compared to the grayscale test.

-    */

-#if 0

-   if (!test_size(pm, 3, 0, 3))

-      return;

-#endif

-

-   if (!test_size(pm, 4, 3, READ_BDHI))

-      return;

-

-   if (!test_size(pm, 6, 3, READ_BDHI))

-      return;

-}

-

-

-/******************************* TRANSFORM TESTS ******************************/

-#ifdef PNG_READ_TRANSFORMS_SUPPORTED

-/* A set of tests to validate libpng image transforms.  The possibilities here

- * are legion because the transforms can be combined in a combinatorial

- * fashion.  To deal with this some measure of restraint is required, otherwise

- * the tests would take forever.

- */

-typedef struct image_pixel

-{

-   /* A local (pngvalid) representation of a PNG pixel, in all its

-    * various forms.

-    */

-   unsigned int red, green, blue, alpha; /* For non-palette images. */

-   unsigned int palette_index;           /* For a palette image. */

-   png_byte colour_type;                 /* As in the spec. */

-   png_byte bit_depth;                   /* Defines bit size in row */

-   png_byte sample_depth;                /* Scale of samples */

-   int      have_tRNS;                   /* tRNS chunk may need processing */

-

-   /* For checking the code calculates double precision floating point values

-    * along with an error value, accumulated from the transforms.  Because an

-    * sBIT setting allows larger error bounds (indeed, by the spec, apparently

-    * up to just less than +/-1 in the scaled value) the *lowest* sBIT for each

-    * channel is stored.  This sBIT value is folded in to the stored error value

-    * at the end of the application of the transforms to the pixel.

-    */

-   double   redf, greenf, bluef, alphaf;

-   double   rede, greene, bluee, alphae;

-   png_byte red_sBIT, green_sBIT, blue_sBIT, alpha_sBIT;

-} image_pixel;

-

-/* Shared utility function, see below. */

-static void

-image_pixel_setf(image_pixel *this, unsigned int max)

-{

-   this->redf = this->red / (double)max;

-   this->greenf = this->green / (double)max;

-   this->bluef = this->blue / (double)max;

-   this->alphaf = this->alpha / (double)max;

-

-   if (this->red < max)

-      this->rede = this->redf * DBL_EPSILON;

-   else

-      this->rede = 0;

-   if (this->green < max)

-      this->greene = this->greenf * DBL_EPSILON;

-   else

-      this->greene = 0;

-   if (this->blue < max)

-      this->bluee = this->bluef * DBL_EPSILON;

-   else

-      this->bluee = 0;

-   if (this->alpha < max)

-      this->alphae = this->alphaf * DBL_EPSILON;

-   else

-      this->alphae = 0;

-}

-

-/* Initialize the structure for the next pixel - call this before doing any

- * transforms and call it for each pixel since all the fields may need to be

- * reset.

- */

-static void

-image_pixel_init(image_pixel *this, png_const_bytep row, png_byte colour_type,

-    png_byte bit_depth, png_uint_32 x, store_palette palette)

-{

-   PNG_CONST png_byte sample_depth = (png_byte)(colour_type ==

-      PNG_COLOR_TYPE_PALETTE ? 8 : bit_depth);

-   PNG_CONST unsigned int max = (1U<<sample_depth)-1;

-

-   /* Initially just set everything to the same number and the alpha to opaque.

-    * Note that this currently assumes a simple palette where entry x has colour

-    * rgb(x,x,x)!

-    */

-   this->palette_index = this->red = this->green = this->blue =

-      sample(row, colour_type, bit_depth, x, 0);

-   this->alpha = max;

-   this->red_sBIT = this->green_sBIT = this->blue_sBIT = this->alpha_sBIT =

-      sample_depth;

-

-   /* Then override as appropriate: */

-   if (colour_type == 3) /* palette */

-   {

-      /* This permits the caller to default to the sample value. */

-      if (palette != 0)

-      {

-         PNG_CONST unsigned int i = this->palette_index;

-

-         this->red = palette[i].red;

-         this->green = palette[i].green;

-         this->blue = palette[i].blue;

-         this->alpha = palette[i].alpha;

-      }

-   }

-

-   else /* not palette */

-   {

-      unsigned int i = 0;

-

-      if (colour_type & 2)

-      {

-         this->green = sample(row, colour_type, bit_depth, x, 1);

-         this->blue = sample(row, colour_type, bit_depth, x, 2);

-         i = 2;

-      }

-      if (colour_type & 4)

-         this->alpha = sample(row, colour_type, bit_depth, x, ++i);

-   }

-

-   /* Calculate the scaled values, these are simply the values divided by

-    * 'max' and the error is initialized to the double precision epsilon value

-    * from the header file.

-    */

-   image_pixel_setf(this, max);

-

-   /* Store the input information for use in the transforms - these will

-    * modify the information.

-    */

-   this->colour_type = colour_type;

-   this->bit_depth = bit_depth;

-   this->sample_depth = sample_depth;

-   this->have_tRNS = 0;

-}

-

-/* Convert a palette image to an rgb image.  This necessarily converts the tRNS

- * chunk at the same time, because the tRNS will be in palette form.  The way

- * palette validation works means that the original palette is never updated,

- * instead the image_pixel value from the row contains the RGB of the

- * corresponding palette entry and *this* is updated.  Consequently this routine

- * only needs to change the colour type information.

- */

-static void

-image_pixel_convert_PLTE(image_pixel *this)

-{

-   if (this->colour_type == PNG_COLOR_TYPE_PALETTE)

-   {

-      if (this->have_tRNS)

-      {

-         this->colour_type = PNG_COLOR_TYPE_RGB_ALPHA;

-         this->have_tRNS = 0;

-      }

-      else

-         this->colour_type = PNG_COLOR_TYPE_RGB;

-

-      /* The bit depth of the row changes at this point too (notice that this is

-       * the row format, not the sample depth, which is separate.)

-       */

-      this->bit_depth = 8;

-   }

-}

-

-/* Add an alpha channel; this will import the tRNS information because tRNS is

- * not valid in an alpha image.  The bit depth will invariably be set to at

- * least 8.  Palette images will be converted to alpha (using the above API).

- */

-static void

-image_pixel_add_alpha(image_pixel *this, PNG_CONST standard_display *display)

-{

-   if (this->colour_type == PNG_COLOR_TYPE_PALETTE)

-      image_pixel_convert_PLTE(this);

-

-   if ((this->colour_type & PNG_COLOR_MASK_ALPHA) == 0)

-   {

-      if (this->colour_type == PNG_COLOR_TYPE_GRAY)

-      {

-         if (this->bit_depth < 8)

-            this->bit_depth = 8;

-

-         if (this->have_tRNS)

-         {

-            this->have_tRNS = 0;

-

-            /* Check the input, original, channel value here against the

-             * original tRNS gray chunk valie.

-             */

-            if (this->red == display->transparent.red)

-               this->alphaf = 0;

-            else

-               this->alphaf = 1;

-         }

-         else

-            this->alphaf = 1;

-

-         this->colour_type = PNG_COLOR_TYPE_GRAY_ALPHA;

-      }

-

-      else if (this->colour_type == PNG_COLOR_TYPE_RGB)

-      {

-         if (this->have_tRNS)

-         {

-            this->have_tRNS = 0;

-

-            /* Again, check the exact input values, not the current transformed

-             * value!

-             */

-            if (this->red == display->transparent.red &&

-               this->green == display->transparent.green &&

-               this->blue == display->transparent.blue)

-               this->alphaf = 0;

-            else

-               this->alphaf = 1;

-

-            this->colour_type = PNG_COLOR_TYPE_RGB_ALPHA;

-         }

-      }

-

-      /* The error in the alpha is zero and the sBIT value comes from the

-       * original sBIT data (actually it will always be the original bit depth).

-       */

-      this->alphae = 0;

-      this->alpha_sBIT = display->alpha_sBIT;

-   }

-}

-

-struct transform_display;

-typedef struct image_transform

-{

-   /* The name of this transform: a string. */

-   PNG_CONST char *name;

-

-   /* Each transform can be disabled from the command line: */

-   int enable;

-

-   /* The global list of transforms; read only. */

-   struct image_transform *PNG_CONST list;

-

-   /* The global count of the number of times this transform has been set on an

-    * image.

-    */

-   unsigned int global_use;

-

-   /* The local count of the number of times this transform has been set. */

-   unsigned int local_use;

-

-   /* The next transform in the list, each transform must call its own next

-    * transform after it has processed the pixel successfully.

-    */

-   PNG_CONST struct image_transform *next;

-

-   /* A single transform for the image, expressed as a series of function

-    * callbacks and some space for values.

-    *

-    * First a callback to add any required modifications to the png_modifier;

-    * this gets called just before the modifier is set up for read.

-    */

-   void (*ini)(PNG_CONST struct image_transform *this,

-      struct transform_display *that);

-

-   /* And a callback to set the transform on the current png_read_struct:

-    */

-   void (*set)(PNG_CONST struct image_transform *this,

-      struct transform_display *that, png_structp pp, png_infop pi);

-

-   /* Then a transform that takes an input pixel in one PNG format or another

-    * and modifies it by a pngvalid implementation of the transform (thus

-    * duplicating the libpng intent without, we hope, duplicating the bugs

-    * in the libpng implementation!)  The png_structp is solely to allow error

-    * reporting via png_error and png_warning.

-    */

-   void (*mod)(PNG_CONST struct image_transform *this, image_pixel *that,

-      png_structp pp, PNG_CONST struct transform_display *display);

-

-   /* Add this transform to the list and return true if the transform is

-    * meaningful for this colour type and bit depth - if false then the

-    * transform should have no effect on the image so there's not a lot of

-    * point running it.

-    */

-   int (*add)(struct image_transform *this,

-      PNG_CONST struct image_transform **that, png_byte colour_type,

-      png_byte bit_depth);

-} image_transform;

-

-typedef struct transform_display

-{

-   standard_display this;

-

-   /* Parameters */

-   png_modifier*              pm;

-   PNG_CONST image_transform* transform_list;

-

-   /* Local variables */

-   png_byte output_colour_type;

-   png_byte output_bit_depth;

-

-   /* Modifications (not necessarily used.) */

-   gama_modification gama_mod;

-   chrm_modification chrm_mod;

-   srgb_modification srgb_mod;

-} transform_display;

-

-/* Set sRGB, cHRM and gAMA transforms as required by the current encoding. */

-static void

-transform_set_encoding(transform_display *this)

-{

-   /* Set up the png_modifier '_current' fields then use these to determine how

-    * to add appropriate chunks.

-    */

-   png_modifier *pm = this->pm;

-

-   modifier_set_encoding(pm);

-

-   if (modifier_color_encoding_is_set(pm))

-   {

-      if (modifier_color_encoding_is_sRGB(pm))

-         srgb_modification_init(&this->srgb_mod, pm, PNG_sRGB_INTENT_ABSOLUTE);

-

-      else

-      {

-         /* Set gAMA and cHRM separately. */

-         gama_modification_init(&this->gama_mod, pm, pm->current_gamma);

-

-         if (pm->current_encoding != 0)

-            chrm_modification_init(&this->chrm_mod, pm, pm->current_encoding);

-      }

-   }

-}

-

-/* Three functions to end the list: */

-static void

-image_transform_ini_end(PNG_CONST image_transform *this,

-   transform_display *that)

-{

-   UNUSED(this)

-   UNUSED(that)

-}

-

-static void

-image_transform_set_end(PNG_CONST image_transform *this,

-   transform_display *that, png_structp pp, png_infop pi)

-{

-   UNUSED(this)

-   UNUSED(that)

-   UNUSED(pp)

-   UNUSED(pi)

-}

-

-/* At the end of the list recalculate the output image pixel value from the

- * double precision values set up by the preceding 'mod' calls:

- */

-static unsigned int

-sample_scale(double sample_value, unsigned int scale)

-{

-   sample_value = floor(sample_value * scale + .5);

-

-   /* Return NaN as 0: */

-   if (!(sample_value > 0))

-      sample_value = 0;

-   else if (sample_value > scale)

-      sample_value = scale;

-

-   return (unsigned int)sample_value;

-}

-

-static void

-image_transform_mod_end(PNG_CONST image_transform *this, image_pixel *that,

-    png_structp pp, PNG_CONST transform_display *display)

-{

-   PNG_CONST unsigned int scale = (1U<<that->sample_depth)-1;

-

-   UNUSED(this)

-   UNUSED(pp)

-   UNUSED(display)

-

-   /* At the end recalculate the digitized red green and blue values according

-    * to the current sample_depth of the pixel.

-    *

-    * The sample value is simply scaled to the maximum, checking for over

-    * and underflow (which can both happen for some image transforms,

-    * including simple size scaling, though libpng doesn't do that at present.

-    */

-   that->red = sample_scale(that->redf, scale);

-

-   /* The error value is increased, at the end, according to the lowest sBIT

-    * value seen.  Common sense tells us that the intermediate integer

-    * representations are no more accurate than +/- 0.5 in the integral values,

-    * the sBIT allows the implementation to be worse than this.  In addition the

-    * PNG specification actually permits any error within the range (-1..+1),

-    * but that is ignored here.  Instead the final digitized value is compared,

-    * below to the digitized value of the error limits - this has the net effect

-    * of allowing (almost) +/-1 in the output value.  It's difficult to see how

-    * any algorithm that digitizes intermediate results can be more accurate.

-    */

-   that->rede += 1./(2*((1U<<that->red_sBIT)-1));

-

-   if (that->colour_type & PNG_COLOR_MASK_COLOR)

-   {

-      that->green = sample_scale(that->greenf, scale);

-      that->blue = sample_scale(that->bluef, scale);

-      that->greene += 1./(2*((1U<<that->green_sBIT)-1));

-      that->bluee += 1./(2*((1U<<that->blue_sBIT)-1));

-   }

-   else

-   {

-      that->blue = that->green = that->red;

-      that->bluef = that->greenf = that->redf;

-      that->bluee = that->greene = that->rede;

-   }

-

-   if ((that->colour_type & PNG_COLOR_MASK_ALPHA) ||

-      that->colour_type == PNG_COLOR_TYPE_PALETTE)

-   {

-      that->alpha = sample_scale(that->alphaf, scale);

-      that->alphae += 1./(2*((1U<<that->alpha_sBIT)-1));

-   }

-   else

-   {

-      that->alpha = scale; /* opaque */

-      that->alpha = 1;     /* Override this. */

-      that->alphae = 0;    /* It's exact ;-) */

-   }

-}

-

-/* Static 'end' structure: */

-static image_transform image_transform_end =

-{

-   "(end)", /* name */

-   1, /* enable */

-   0, /* list */

-   0, /* global_use */

-   0, /* local_use */

-   0, /* next */

-   image_transform_ini_end,

-   image_transform_set_end,

-   image_transform_mod_end,

-   0 /* never called, I want it to crash if it is! */

-};

-

-/* Reader callbacks and implementations, where they differ from the standard

- * ones.

- */

-static void

-transform_display_init(transform_display *dp, png_modifier *pm, png_uint_32 id,

-    PNG_CONST image_transform *transform_list)

-{

-   memset(dp, 0, sizeof *dp);

-

-   /* Standard fields */

-   standard_display_init(&dp->this, &pm->this, id, 0/*do_interlace*/,

-      pm->use_update_info);

-

-   /* Parameter fields */

-   dp->pm = pm;

-   dp->transform_list = transform_list;

-

-   /* Local variable fields */

-   dp->output_colour_type = 255; /* invalid */

-   dp->output_bit_depth = 255;  /* invalid */

-}

-

-static void

-transform_info_imp(transform_display *dp, png_structp pp, png_infop pi)

-{

-   /* Reuse the standard stuff as appropriate. */

-   standard_info_part1(&dp->this, pp, pi);

-

-   /* Now set the list of transforms. */

-   dp->transform_list->set(dp->transform_list, dp, pp, pi);

-

-   /* Update the info structure for these transforms: */

-   {

-      int i = dp->this.use_update_info;

-      /* Always do one call, even if use_update_info is 0. */

-      do

-         png_read_update_info(pp, pi);

-      while (--i > 0);

-   }

-

-   /* And get the output information into the standard_display */

-   standard_info_part2(&dp->this, pp, pi, 1/*images*/);

-

-   /* Plus the extra stuff we need for the transform tests: */

-   dp->output_colour_type = png_get_color_type(pp, pi);

-   dp->output_bit_depth = png_get_bit_depth(pp, pi);

-

-   /* Validate the combination of colour type and bit depth that we are getting

-    * out of libpng; the semantics of something not in the PNG spec are, at

-    * best, unclear.

-    */

-   switch (dp->output_colour_type)

-   {

-   case PNG_COLOR_TYPE_PALETTE:

-      if (dp->output_bit_depth > 8) goto error;

-      /*FALL THROUGH*/

-   case PNG_COLOR_TYPE_GRAY:

-      if (dp->output_bit_depth == 1 || dp->output_bit_depth == 2 ||

-         dp->output_bit_depth == 4)

-         break;

-      /*FALL THROUGH*/

-   default:

-      if (dp->output_bit_depth == 8 || dp->output_bit_depth == 16)

-         break;

-      /*FALL THROUGH*/

-   error:

-      {

-         char message[128];

-         size_t pos;

-

-         pos = safecat(message, sizeof message, 0,

-            "invalid final bit depth: colour type(");

-         pos = safecatn(message, sizeof message, pos, dp->output_colour_type);

-         pos = safecat(message, sizeof message, pos, ") with bit depth: ");

-         pos = safecatn(message, sizeof message, pos, dp->output_bit_depth);

-

-         png_error(pp, message);

-      }

-   }

-

-   /* Use a test pixel to check that the output agrees with what we expect -

-    * this avoids running the whole test if the output is unexpected.

-    */

-   {

-      image_pixel test_pixel;

-

-      memset(&test_pixel, 0, sizeof test_pixel);

-      test_pixel.colour_type = dp->this.colour_type; /* input */

-      test_pixel.bit_depth = dp->this.bit_depth;

-      if (test_pixel.colour_type == PNG_COLOR_TYPE_PALETTE)

-         test_pixel.sample_depth = 8;

-      else

-         test_pixel.sample_depth = test_pixel.bit_depth;

-      /* Don't need sBIT here, but it must be set to non-zero to avoid

-       * arithmetic overflows.

-       */

-      test_pixel.have_tRNS = dp->this.is_transparent;

-      test_pixel.red_sBIT = test_pixel.green_sBIT = test_pixel.blue_sBIT =

-         test_pixel.alpha_sBIT = test_pixel.sample_depth;

-

-      dp->transform_list->mod(dp->transform_list, &test_pixel, pp, dp);

-

-      if (test_pixel.colour_type != dp->output_colour_type)

-      {

-         char message[128];

-         size_t pos = safecat(message, sizeof message, 0, "colour type ");

-

-         pos = safecatn(message, sizeof message, pos, dp->output_colour_type);

-         pos = safecat(message, sizeof message, pos, " expected ");

-         pos = safecatn(message, sizeof message, pos, test_pixel.colour_type);

-

-         png_error(pp, message);

-      }

-

-      if (test_pixel.bit_depth != dp->output_bit_depth)

-      {

-         char message[128];

-         size_t pos = safecat(message, sizeof message, 0, "bit depth ");

-

-         pos = safecatn(message, sizeof message, pos, dp->output_bit_depth);

-         pos = safecat(message, sizeof message, pos, " expected ");

-         pos = safecatn(message, sizeof message, pos, test_pixel.bit_depth);

-

-         png_error(pp, message);

-      }

-

-      /* If both bit depth and colour type are correct check the sample depth.

-       * I believe these are both internal errors.

-       */

-      if (test_pixel.colour_type == PNG_COLOR_TYPE_PALETTE)

-      {

-         if (test_pixel.sample_depth != 8) /* oops - internal error! */

-            png_error(pp, "pngvalid: internal: palette sample depth not 8");

-      }

-      else if (test_pixel.sample_depth != dp->output_bit_depth)

-      {

-         char message[128];

-         size_t pos = safecat(message, sizeof message, 0,

-            "internal: sample depth ");

-

-         pos = safecatn(message, sizeof message, pos, dp->output_bit_depth);

-         pos = safecat(message, sizeof message, pos, " expected ");

-         pos = safecatn(message, sizeof message, pos, test_pixel.sample_depth);

-

-         png_error(pp, message);

-      }

-   }

-}

-

-static void

-transform_info(png_structp pp, png_infop pi)

-{

-   transform_info_imp(voidcast(transform_display*, png_get_progressive_ptr(pp)),

-      pp, pi);

-}

-

-static void

-transform_range_check(png_structp pp, unsigned int r, unsigned int g,

-   unsigned int b, unsigned int a, unsigned int in_digitized, double in,

-   unsigned int out, png_byte sample_depth, double err, double limit,

-   PNG_CONST char *name, double digitization_error)

-{

-   /* Compare the scaled, digitzed, values of our local calculation (in+-err)

-    * with the digitized values libpng produced;  'sample_depth' is the actual

-    * digitization depth of the libpng output colors (the bit depth except for

-    * palette images where it is always 8.)  The check on 'err' is to detect

-    * internal errors in pngvalid itself.

-    */

-   unsigned int max = (1U<<sample_depth)-1;

-   double in_min = ceil((in-err)*max - digitization_error);

-   double in_max = floor((in+err)*max + digitization_error);

-   if (err > limit || !(out >= in_min && out <= in_max))

-   {

-      char message[256];

-      size_t pos;

-

-      pos = safecat(message, sizeof message, 0, name);

-      pos = safecat(message, sizeof message, pos, " output value error: rgba(");

-      pos = safecatn(message, sizeof message, pos, r);

-      pos = safecat(message, sizeof message, pos, ",");

-      pos = safecatn(message, sizeof message, pos, g);

-      pos = safecat(message, sizeof message, pos, ",");

-      pos = safecatn(message, sizeof message, pos, b);

-      pos = safecat(message, sizeof message, pos, ",");

-      pos = safecatn(message, sizeof message, pos, a);

-      pos = safecat(message, sizeof message, pos, "): ");

-      pos = safecatn(message, sizeof message, pos, out);

-      pos = safecat(message, sizeof message, pos, " expected: ");

-      pos = safecatn(message, sizeof message, pos, in_digitized);

-      pos = safecat(message, sizeof message, pos, " (");

-      pos = safecatd(message, sizeof message, pos, (in-err)*max, 3);

-      pos = safecat(message, sizeof message, pos, "..");

-      pos = safecatd(message, sizeof message, pos, (in+err)*max, 3);

-      pos = safecat(message, sizeof message, pos, ")");

-

-      png_error(pp, message);

-   }

-}

-

-static void

-transform_image_validate(transform_display *dp, png_structp pp, png_infop pi)

-{

-   /* Constants for the loop below: */

-   PNG_CONST png_store* PNG_CONST ps = dp->this.ps;

-   PNG_CONST png_byte in_ct = dp->this.colour_type;

-   PNG_CONST png_byte in_bd = dp->this.bit_depth;

-   PNG_CONST png_uint_32 w = dp->this.w;

-   PNG_CONST png_uint_32 h = dp->this.h;

-   PNG_CONST png_byte out_ct = dp->output_colour_type;

-   PNG_CONST png_byte out_bd = dp->output_bit_depth;

-   PNG_CONST png_byte sample_depth = (png_byte)(out_ct ==

-      PNG_COLOR_TYPE_PALETTE ? 8 : out_bd);

-   PNG_CONST png_byte red_sBIT = dp->this.red_sBIT;

-   PNG_CONST png_byte green_sBIT = dp->this.green_sBIT;

-   PNG_CONST png_byte blue_sBIT = dp->this.blue_sBIT;

-   PNG_CONST png_byte alpha_sBIT = dp->this.alpha_sBIT;

-   PNG_CONST int have_tRNS = dp->this.is_transparent;

-   double digitization_error;

-

-   store_palette out_palette;

-   png_uint_32 y;

-

-   UNUSED(pi)

-

-   /* Check for row overwrite errors */

-   store_image_check(dp->this.ps, pp, 0);

-

-   /* Read the palette corresponding to the output if the output colour type

-    * indicates a palette, othewise set out_palette to garbage.

-    */

-   if (out_ct == PNG_COLOR_TYPE_PALETTE)

-   {

-      /* Validate that the palette count itself has not changed - this is not

-       * expected.

-       */

-      int npalette = (-1);

-

-      (void)read_palette(out_palette, &npalette, pp, pi);

-      if (npalette != dp->this.npalette)

-         png_error(pp, "unexpected change in palette size");

-

-      digitization_error = .5;

-   }

-   else

-   {

-      png_byte in_sample_depth;

-

-      memset(out_palette, 0x5e, sizeof out_palette);

-

-      /* assume-8-bit-calculations means assume that if the input has 8 bit

-       * (or less) samples and the output has 16 bit samples the calculations

-       * will be done with 8 bit precision, not 16.

-       *

-       * TODO: fix this in libpng; png_set_expand_16 should cause 16 bit

-       * calculations to be used throughout.

-       */

-      if (in_ct == PNG_COLOR_TYPE_PALETTE || in_bd < 16)

-         in_sample_depth = 8;

-      else

-         in_sample_depth = in_bd;

-

-      if (sample_depth != 16 || in_sample_depth > 8 ||

-         !dp->pm->calculations_use_input_precision)

-         digitization_error = .5;

-

-      /* Else errors are at 8 bit precision, scale .5 in 8 bits to the 16 bits:

-       */

-      else

-         digitization_error = .5 * 257;

-   }

-

-   for (y=0; y<h; ++y)

-   {

-      png_const_bytep PNG_CONST pRow = store_image_row(ps, pp, 0, y);

-      png_uint_32 x;

-

-      /* The original, standard, row pre-transforms. */

-      png_byte std[STANDARD_ROWMAX];

-

-      transform_row(pp, std, in_ct, in_bd, y);

-

-      /* Go through each original pixel transforming it and comparing with what

-       * libpng did to the same pixel.

-       */

-      for (x=0; x<w; ++x)

-      {

-         image_pixel in_pixel, out_pixel;

-         unsigned int r, g, b, a;

-

-         /* Find out what we think the pixel should be: */

-         image_pixel_init(&in_pixel, std, in_ct, in_bd, x, dp->this.palette);

-

-         in_pixel.red_sBIT = red_sBIT;

-         in_pixel.green_sBIT = green_sBIT;

-         in_pixel.blue_sBIT = blue_sBIT;

-         in_pixel.alpha_sBIT = alpha_sBIT;

-         in_pixel.have_tRNS = have_tRNS;

-

-         /* For error detection, below. */

-         r = in_pixel.red;

-         g = in_pixel.green;

-         b = in_pixel.blue;

-         a = in_pixel.alpha;

-

-         dp->transform_list->mod(dp->transform_list, &in_pixel, pp, dp);

-

-         /* Read the output pixel and compare it to what we got, we don't

-          * use the error field here, so no need to update sBIT.

-          */

-         image_pixel_init(&out_pixel, pRow, out_ct, out_bd, x, out_palette);

-

-         /* We don't expect changes to the index here even if the bit depth is

-          * changed.

-          */

-         if (in_ct == PNG_COLOR_TYPE_PALETTE &&

-            out_ct == PNG_COLOR_TYPE_PALETTE)

-         {

-            if (in_pixel.palette_index != out_pixel.palette_index)

-               png_error(pp, "unexpected transformed palette index");

-         }

-

-         /* Check the colours for palette images too - in fact the palette could

-          * be separately verified itself in most cases.

-          */

-         if (in_pixel.red != out_pixel.red)

-            transform_range_check(pp, r, g, b, a, in_pixel.red, in_pixel.redf,

-               out_pixel.red, sample_depth, in_pixel.rede,

-               dp->pm->limit + 1./(2*((1U<<in_pixel.red_sBIT)-1)), "red/gray",

-               digitization_error);

-

-         if ((out_ct & PNG_COLOR_MASK_COLOR) != 0 &&

-            in_pixel.green != out_pixel.green)

-            transform_range_check(pp, r, g, b, a, in_pixel.green,

-               in_pixel.greenf, out_pixel.green, sample_depth, in_pixel.greene,

-               dp->pm->limit + 1./(2*((1U<<in_pixel.green_sBIT)-1)), "green",

-               digitization_error);

-

-         if ((out_ct & PNG_COLOR_MASK_COLOR) != 0 &&

-            in_pixel.blue != out_pixel.blue)

-            transform_range_check(pp, r, g, b, a, in_pixel.blue, in_pixel.bluef,

-               out_pixel.blue, sample_depth, in_pixel.bluee,

-               dp->pm->limit + 1./(2*((1U<<in_pixel.blue_sBIT)-1)), "blue",

-               digitization_error);

-

-         if ((out_ct & PNG_COLOR_MASK_ALPHA) != 0 &&

-            in_pixel.alpha != out_pixel.alpha)

-            transform_range_check(pp, r, g, b, a, in_pixel.alpha,

-               in_pixel.alphaf, out_pixel.alpha, sample_depth, in_pixel.alphae,

-               dp->pm->limit + 1./(2*((1U<<in_pixel.alpha_sBIT)-1)), "alpha",

-               digitization_error);

-      } /* pixel (x) loop */

-   } /* row (y) loop */

-

-   /* Record that something was actually checked to avoid a false positive. */

-   dp->this.ps->validated = 1;

-}

-

-static void

-transform_end(png_structp pp, png_infop pi)

-{

-   transform_display *dp = voidcast(transform_display*,

-      png_get_progressive_ptr(pp));

-

-   if (!dp->this.speed)

-      transform_image_validate(dp, pp, pi);

-   else

-      dp->this.ps->validated = 1;

-}

-

-/* A single test run. */

-static void

-transform_test(png_modifier *pmIn, PNG_CONST png_uint_32 idIn,

-    PNG_CONST image_transform* transform_listIn, PNG_CONST char * volatile name)

-{

-   transform_display d;

-   context(&pmIn->this, fault);

-

-   transform_display_init(&d, pmIn, idIn, transform_listIn);

-

-   Try

-   {

-      size_t pos = 0;

-      png_structp pp;

-      png_infop pi;

-      char full_name[256];

-

-      /* Make sure the encoding fields are correct and enter the required

-       * modifications.

-       */

-      transform_set_encoding(&d);

-

-      /* Add any modifications required by the transform list. */

-      d.transform_list->ini(d.transform_list, &d);

-

-      /* Add the color space information, if any, to the name. */

-      pos = safecat(full_name, sizeof full_name, pos, name);

-      pos = safecat_current_encoding(full_name, sizeof full_name, pos, d.pm);

-

-      /* Get a png_struct for reading the image. */

-      pp = set_modifier_for_read(d.pm, &pi, d.this.id, full_name);

-      standard_palette_init(&d.this);

-

-#     if 0

-         /* Logging (debugging only) */

-         {

-            char buffer[256];

-

-            (void)store_message(&d.pm->this, pp, buffer, sizeof buffer, 0,

-               "running test");

-

-            fprintf(stderr, "%s\n", buffer);

-         }

-#     endif

-

-      /* Introduce the correct read function. */

-      if (d.pm->this.progressive)

-      {

-         /* Share the row function with the standard implementation. */

-         png_set_progressive_read_fn(pp, &d, transform_info, progressive_row,

-            transform_end);

-

-         /* Now feed data into the reader until we reach the end: */

-         modifier_progressive_read(d.pm, pp, pi);

-      }

-      else

-      {

-         /* modifier_read expects a png_modifier* */

-         png_set_read_fn(pp, d.pm, modifier_read);

-

-         /* Check the header values: */

-         png_read_info(pp, pi);

-

-         /* Process the 'info' requirements. Only one image is generated */

-         transform_info_imp(&d, pp, pi);

-

-         sequential_row(&d.this, pp, pi, -1, 0);

-

-         if (!d.this.speed)

-            transform_image_validate(&d, pp, pi);

-         else

-            d.this.ps->validated = 1;

-      }

-

-      modifier_reset(d.pm);

-   }

-

-   Catch(fault)

-   {

-      modifier_reset((png_modifier*)fault);

-   }

-}

-

-/* The transforms: */

-#define ITSTRUCT(name) image_transform_##name

-#define ITDATA(name) image_transform_data_##name

-#define image_transform_ini image_transform_default_ini

-#define IT(name)\

-static image_transform ITSTRUCT(name) =\

-{\

-   #name,\

-   1, /*enable*/\

-   &PT, /*list*/\

-   0, /*global_use*/\

-   0, /*local_use*/\

-   0, /*next*/\

-   image_transform_ini,\

-   image_transform_png_set_##name##_set,\

-   image_transform_png_set_##name##_mod,\

-   image_transform_png_set_##name##_add\

-}

-#define PT ITSTRUCT(end) /* stores the previous transform */

-

-/* To save code: */

-static void

-image_transform_default_ini(PNG_CONST image_transform *this,

-    transform_display *that)

-{

-   this->next->ini(this->next, that);

-}

-

-static int

-image_transform_default_add(image_transform *this,

-    PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth)

-{

-   UNUSED(colour_type)

-   UNUSED(bit_depth)

-

-   this->next = *that;

-   *that = this;

-

-   return 1;

-}

-

-#ifdef PNG_READ_EXPAND_SUPPORTED

-/* png_set_palette_to_rgb */

-static void

-image_transform_png_set_palette_to_rgb_set(PNG_CONST image_transform *this,

-    transform_display *that, png_structp pp, png_infop pi)

-{

-   png_set_palette_to_rgb(pp);

-   this->next->set(this->next, that, pp, pi);

-}

-

-static void

-image_transform_png_set_palette_to_rgb_mod(PNG_CONST image_transform *this,

-    image_pixel *that, png_structp pp, PNG_CONST transform_display *display)

-{

-   if (that->colour_type == PNG_COLOR_TYPE_PALETTE)

-      image_pixel_convert_PLTE(that);

-

-   this->next->mod(this->next, that, pp, display);

-}

-

-static int

-image_transform_png_set_palette_to_rgb_add(image_transform *this,

-    PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth)

-{

-   UNUSED(bit_depth)

-

-   this->next = *that;

-   *that = this;

-

-   return colour_type == PNG_COLOR_TYPE_PALETTE;

-}

-

-IT(palette_to_rgb);

-#undef PT

-#define PT ITSTRUCT(palette_to_rgb)

-#endif /* PNG_READ_EXPAND_SUPPORTED */

-

-#ifdef PNG_READ_EXPAND_SUPPORTED

-/* png_set_tRNS_to_alpha */

-static void

-image_transform_png_set_tRNS_to_alpha_set(PNG_CONST image_transform *this,

-   transform_display *that, png_structp pp, png_infop pi)

-{

-   png_set_tRNS_to_alpha(pp);

-   this->next->set(this->next, that, pp, pi);

-}

-

-static void

-image_transform_png_set_tRNS_to_alpha_mod(PNG_CONST image_transform *this,

-   image_pixel *that, png_structp pp, PNG_CONST transform_display *display)

-{

-   /* LIBPNG BUG: this always forces palette images to RGB. */

-   if (that->colour_type == PNG_COLOR_TYPE_PALETTE)

-      image_pixel_convert_PLTE(that);

-

-   /* This effectively does an 'expand' only if there is some transparency to

-    * convert to an alpha channel.

-    */

-   if (that->have_tRNS)

-      image_pixel_add_alpha(that, &display->this);

-

-   /* LIBPNG BUG: otherwise libpng still expands to 8 bits! */

-   else

-   {

-      if (that->bit_depth < 8)

-         that->bit_depth =8;

-      if (that->sample_depth < 8)

-         that->sample_depth = 8;

-   }

-

-   this->next->mod(this->next, that, pp, display);

-}

-

-static int

-image_transform_png_set_tRNS_to_alpha_add(image_transform *this,

-    PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth)

-{

-   UNUSED(bit_depth)

-

-   this->next = *that;

-   *that = this;

-

-   /* We don't know yet whether there will be a tRNS chunk, but we know that

-    * this transformation should do nothing if there already is an alpha

-    * channel.

-    */

-   return (colour_type & PNG_COLOR_MASK_ALPHA) == 0;

-}

-

-IT(tRNS_to_alpha);

-#undef PT

-#define PT ITSTRUCT(tRNS_to_alpha)

-#endif /* PNG_READ_EXPAND_SUPPORTED */

-

-#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED

-/* png_set_gray_to_rgb */

-static void

-image_transform_png_set_gray_to_rgb_set(PNG_CONST image_transform *this,

-    transform_display *that, png_structp pp, png_infop pi)

-{

-   png_set_gray_to_rgb(pp);

-   this->next->set(this->next, that, pp, pi);

-}

-

-static void

-image_transform_png_set_gray_to_rgb_mod(PNG_CONST image_transform *this,

-    image_pixel *that, png_structp pp, PNG_CONST transform_display *display)

-{

-   /* NOTE: we can actually pend the tRNS processing at this point because we

-    * can correctly recognize the original pixel value even though we have

-    * mapped the one gray channel to the three RGB ones, but in fact libpng

-    * doesn't do this, so we don't either.

-    */

-   if ((that->colour_type & PNG_COLOR_MASK_COLOR) == 0 && that->have_tRNS)

-      image_pixel_add_alpha(that, &display->this);

-

-   /* Simply expand the bit depth and alter the colour type as required. */

-   if (that->colour_type == PNG_COLOR_TYPE_GRAY)

-   {

-      /* RGB images have a bit depth at least equal to '8' */

-      if (that->bit_depth < 8)

-         that->sample_depth = that->bit_depth = 8;

-

-      /* And just changing the colour type works here because the green and blue

-       * channels are being maintained in lock-step with the red/gray:

-       */

-      that->colour_type = PNG_COLOR_TYPE_RGB;

-   }

-

-   else if (that->colour_type == PNG_COLOR_TYPE_GRAY_ALPHA)

-      that->colour_type = PNG_COLOR_TYPE_RGB_ALPHA;

-

-   this->next->mod(this->next, that, pp, display);

-}

-

-static int

-image_transform_png_set_gray_to_rgb_add(image_transform *this,

-    PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth)

-{

-   UNUSED(bit_depth)

-

-   this->next = *that;

-   *that = this;

-

-   return (colour_type & PNG_COLOR_MASK_COLOR) == 0;

-}

-

-IT(gray_to_rgb);

-#undef PT

-#define PT ITSTRUCT(gray_to_rgb)

-#endif /* PNG_READ_GRAY_TO_RGB_SUPPORTED */

-

-#ifdef PNG_READ_EXPAND_SUPPORTED

-/* png_set_expand */

-static void

-image_transform_png_set_expand_set(PNG_CONST image_transform *this,

-    transform_display *that, png_structp pp, png_infop pi)

-{

-   png_set_expand(pp);

-   this->next->set(this->next, that, pp, pi);

-}

-

-static void

-image_transform_png_set_expand_mod(PNG_CONST image_transform *this,

-    image_pixel *that, png_structp pp, PNG_CONST transform_display *display)

-{

-   /* The general expand case depends on what the colour type is: */

-   if (that->colour_type == PNG_COLOR_TYPE_PALETTE)

-      image_pixel_convert_PLTE(that);

-   else if (that->bit_depth < 8) /* grayscale */

-      that->sample_depth = that->bit_depth = 8;

-

-   if (that->have_tRNS)

-      image_pixel_add_alpha(that, &display->this);

-

-   this->next->mod(this->next, that, pp, display);

-}

-

-static int

-image_transform_png_set_expand_add(image_transform *this,

-    PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth)

-{

-   UNUSED(bit_depth)

-

-   this->next = *that;

-   *that = this;

-

-   /* 'expand' should do nothing for RGBA or GA input - no tRNS and the bit

-    * depth is at least 8 already.

-    */

-   return (colour_type & PNG_COLOR_MASK_ALPHA) == 0;

-}

-

-IT(expand);

-#undef PT

-#define PT ITSTRUCT(expand)

-#endif /* PNG_READ_EXPAND_SUPPORTED */

-

-#ifdef PNG_READ_EXPAND_SUPPORTED

-/* png_set_expand_gray_1_2_4_to_8

- * LIBPNG BUG: this just does an 'expand'

- */

-static void

-image_transform_png_set_expand_gray_1_2_4_to_8_set(

-    PNG_CONST image_transform *this, transform_display *that, png_structp pp,

-    png_infop pi)

-{

-   png_set_expand_gray_1_2_4_to_8(pp);

-   this->next->set(this->next, that, pp, pi);

-}

-

-static void

-image_transform_png_set_expand_gray_1_2_4_to_8_mod(

-    PNG_CONST image_transform *this, image_pixel *that, png_structp pp,

-    PNG_CONST transform_display *display)

-{

-   image_transform_png_set_expand_mod(this, that, pp, display);

-}

-

-static int

-image_transform_png_set_expand_gray_1_2_4_to_8_add(image_transform *this,

-    PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth)

-{

-   return image_transform_png_set_expand_add(this, that, colour_type,

-      bit_depth);

-}

-

-IT(expand_gray_1_2_4_to_8);

-#undef PT

-#define PT ITSTRUCT(expand_gray_1_2_4_to_8)

-#endif /* PNG_READ_EXPAND_SUPPORTED */

-

-#ifdef PNG_READ_EXPAND_16_SUPPORTED

-/* png_set_expand_16 */

-static void

-image_transform_png_set_expand_16_set(PNG_CONST image_transform *this,

-    transform_display *that, png_structp pp, png_infop pi)

-{

-   png_set_expand_16(pp);

-   this->next->set(this->next, that, pp, pi);

-}

-

-static void

-image_transform_png_set_expand_16_mod(PNG_CONST image_transform *this,

-    image_pixel *that, png_structp pp, PNG_CONST transform_display *display)

-{

-   /* Expect expand_16 to expand everything to 16 bits as a result of also

-    * causing 'expand' to happen.

-    */

-   if (that->colour_type == PNG_COLOR_TYPE_PALETTE)

-      image_pixel_convert_PLTE(that);

-

-   if (that->have_tRNS)

-      image_pixel_add_alpha(that, &display->this);

-

-   if (that->bit_depth < 16)

-      that->sample_depth = that->bit_depth = 16;

-

-   this->next->mod(this->next, that, pp, display);

-}

-

-static int

-image_transform_png_set_expand_16_add(image_transform *this,

-    PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth)

-{

-   UNUSED(colour_type)

-

-   this->next = *that;

-   *that = this;

-

-   /* expand_16 does something unless the bit depth is already 16. */

-   return bit_depth < 16;

-}

-

-IT(expand_16);

-#undef PT

-#define PT ITSTRUCT(expand_16)

-#endif /* PNG_READ_EXPAND_16_SUPPORTED */

-

-#ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED  /* API added in 1.5.4 */

-/* png_set_scale_16 */

-static void

-image_transform_png_set_scale_16_set(PNG_CONST image_transform *this,

-    transform_display *that, png_structp pp, png_infop pi)

-{

-   png_set_scale_16(pp);

-   this->next->set(this->next, that, pp, pi);

-}

-

-static void

-image_transform_png_set_scale_16_mod(PNG_CONST image_transform *this,

-    image_pixel *that, png_structp pp, PNG_CONST transform_display *display)

-{

-   if (that->bit_depth == 16)

-   {

-      that->sample_depth = that->bit_depth = 8;

-      if (that->red_sBIT > 8) that->red_sBIT = 8;

-      if (that->green_sBIT > 8) that->green_sBIT = 8;

-      if (that->blue_sBIT > 8) that->blue_sBIT = 8;

-      if (that->alpha_sBIT > 8) that->alpha_sBIT = 8;

-   }

-

-   this->next->mod(this->next, that, pp, display);

-}

-

-static int

-image_transform_png_set_scale_16_add(image_transform *this,

-    PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth)

-{

-   UNUSED(colour_type)

-

-   this->next = *that;

-   *that = this;

-

-   return bit_depth > 8;

-}

-

-IT(scale_16);

-#undef PT

-#define PT ITSTRUCT(scale_16)

-#endif /* PNG_READ_SCALE_16_TO_8_SUPPORTED (1.5.4 on) */

-

-#ifdef PNG_READ_16_TO_8_SUPPORTED /* the default before 1.5.4 */

-/* png_set_strip_16 */

-static void

-image_transform_png_set_strip_16_set(PNG_CONST image_transform *this,

-    transform_display *that, png_structp pp, png_infop pi)

-{

-   png_set_strip_16(pp);

-   this->next->set(this->next, that, pp, pi);

-}

-

-static void

-image_transform_png_set_strip_16_mod(PNG_CONST image_transform *this,

-    image_pixel *that, png_structp pp, PNG_CONST transform_display *display)

-{

-   if (that->bit_depth == 16)

-   {

-      that->sample_depth = that->bit_depth = 8;

-      if (that->red_sBIT > 8) that->red_sBIT = 8;

-      if (that->green_sBIT > 8) that->green_sBIT = 8;

-      if (that->blue_sBIT > 8) that->blue_sBIT = 8;

-      if (that->alpha_sBIT > 8) that->alpha_sBIT = 8;

-

-      /* Prior to 1.5.4 png_set_strip_16 would use an 'accurate' method if this

-       * configuration option is set.  From 1.5.4 the flag is never set and the

-       * 'scale' API (above) must be used.

-       */

-#     ifdef PNG_READ_ACCURATE_SCALE_SUPPORTED

-#        if PNG_LIBPNG_VER >= 10504

-#           error PNG_READ_ACCURATE_SCALE should not be set

-#        endif

-

-         /* The strip 16 algorithm drops the low 8 bits rather than calculating

-          * 1/257, so we need to adjust the permitted errors appropriately:

-          * Notice that this is only relevant prior to the addition of the

-          * png_set_scale_16 API in 1.5.4 (but 1.5.4+ always defines the above!)

-          */

-         {

-            PNG_CONST double d = (255-128.5)/65535;

-            that->rede += d;

-            that->greene += d;

-            that->bluee += d;

-            that->alphae += d;

-         }

-#     endif

-   }

-

-   this->next->mod(this->next, that, pp, display);

-}

-

-static int

-image_transform_png_set_strip_16_add(image_transform *this,

-    PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth)

-{

-   UNUSED(colour_type)

-

-   this->next = *that;

-   *that = this;

-

-   return bit_depth > 8;

-}

-

-IT(strip_16);

-#undef PT

-#define PT ITSTRUCT(strip_16)

-#endif /* PNG_READ_16_TO_8_SUPPORTED */

-

-#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED

-/* png_set_strip_alpha */

-static void

-image_transform_png_set_strip_alpha_set(PNG_CONST image_transform *this,

-    transform_display *that, png_structp pp, png_infop pi)

-{

-   png_set_strip_alpha(pp);

-   this->next->set(this->next, that, pp, pi);

-}

-

-static void

-image_transform_png_set_strip_alpha_mod(PNG_CONST image_transform *this,

-    image_pixel *that, png_structp pp, PNG_CONST transform_display *display)

-{

-   if (that->colour_type == PNG_COLOR_TYPE_GRAY_ALPHA)

-      that->colour_type = PNG_COLOR_TYPE_GRAY;

-   else if (that->colour_type == PNG_COLOR_TYPE_RGB_ALPHA)

-      that->colour_type = PNG_COLOR_TYPE_RGB;

-

-   that->have_tRNS = 0;

-   that->alphaf = 1;

-

-   this->next->mod(this->next, that, pp, display);

-}

-

-static int

-image_transform_png_set_strip_alpha_add(image_transform *this,

-    PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth)

-{

-   UNUSED(bit_depth)

-

-   this->next = *that;

-   *that = this;

-

-   return (colour_type & PNG_COLOR_MASK_ALPHA) != 0;

-}

-

-IT(strip_alpha);

-#undef PT

-#define PT ITSTRUCT(strip_alpha)

-#endif /* PNG_READ_STRIP_ALPHA_SUPPORTED */

-

-#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED

-/* png_set_rgb_to_gray(png_structp, int err_action, double red, double green)

- * png_set_rgb_to_gray_fixed(png_structp, int err_action, png_fixed_point red,

- *    png_fixed_point green)

- * png_get_rgb_to_gray_status

- *

- * The 'default' test here uses values known to be used inside libpng:

- *

- *   red:    6968

- *   green: 23434

- *   blue:   2366

- *

- * These values are being retained for compatibility, along with the somewhat

- * broken truncation calculation in the fast-and-inaccurate code path.  Older

- * versions of libpng will fail the accuracy tests below because they use the

- * truncation algorithm everywhere.

- */

-#define data ITDATA(rgb_to_gray)

-static struct

-{

-   double gamma;      /* File gamma to use in processing */

-

-   /* The following are the parameters for png_set_rgb_to_gray: */

-#  ifdef PNG_FLOATING_POINT_SUPPORTED

-      double red_to_set;

-      double green_to_set;

-#  else

-      png_fixed_point red_to_set;

-      png_fixed_point green_to_set;

-#  endif

-

-   /* The actual coefficients: */

-   double red_coefficient;

-   double green_coefficient;

-   double blue_coefficient;

-

-   /* Set if the coeefficients have been overridden. */

-   int coefficients_overridden;

-} data;

-

-#undef image_transform_ini

-#define image_transform_ini image_transform_png_set_rgb_to_gray_ini

-static void

-image_transform_png_set_rgb_to_gray_ini(PNG_CONST image_transform *this,

-    transform_display *that)

-{

-   png_modifier *pm = that->pm;

-   PNG_CONST color_encoding *e = pm->current_encoding;

-

-   UNUSED(this)

-

-   /* Since we check the encoding this flag must be set: */

-   pm->test_uses_encoding = 1;

-

-   /* If 'e' is not NULL chromaticity information is present and either a cHRM

-    * or an sRGB chunk will be inserted.

-    */

-   if (e != 0)

-   {

-      /* Coefficients come from the encoding, but may need to be normalized to a

-       * white point Y of 1.0

-       */

-      PNG_CONST double whiteY = e->red.Y + e->green.Y + e->blue.Y;

-

-      data.red_coefficient = e->red.Y;

-      data.green_coefficient = e->green.Y;

-      data.blue_coefficient = e->blue.Y;

-

-      if (whiteY != 1)

-      {

-         data.red_coefficient /= whiteY;

-         data.green_coefficient /= whiteY;

-         data.blue_coefficient /= whiteY;

-      }

-   }

-

-   else

-   {

-      /* The default (built in) coeffcients, as above: */

-      data.red_coefficient = 6968 / 32768.;

-      data.green_coefficient = 23434 / 32768.;

-      data.blue_coefficient = 2366 / 32768.;

-   }

-

-   data.gamma = pm->current_gamma;

-

-   /* If not set then the calculations assume linear encoding (implicitly): */

-   if (data.gamma == 0)

-      data.gamma = 1;

-

-   /* The arguments to png_set_rgb_to_gray can override the coefficients implied

-    * by the color space encoding.  If doing exhaustive checks do the override

-    * in each case, otherwise do it randomly.

-    */

-   if (pm->test_exhaustive)

-   {

-      /* First time in coefficients_overridden is 0, the following sets it to 1,

-       * so repeat if it is set.  If a test fails this may mean we subsequently

-       * skip a non-override test, ignore that.

-       */

-      data.coefficients_overridden = !data.coefficients_overridden;

-      pm->repeat = data.coefficients_overridden != 0;

-   }

-

-   else

-      data.coefficients_overridden = random_choice();

-

-   if (data.coefficients_overridden)

-   {

-      /* These values override the color encoding defaults, simply use random

-       * numbers.

-       */

-      png_uint_32 ru;

-      double total;

-

-      RANDOMIZE(ru);

-      data.green_coefficient = total = (ru & 0xffff) / 65535.;

-      ru >>= 16;

-      data.red_coefficient = (1 - total) * (ru & 0xffff) / 65535.;

-      total += data.red_coefficient;

-      data.blue_coefficient = 1 - total;

-

-#     ifdef PNG_FLOATING_POINT_SUPPORTED

-         data.red_to_set = data.red_coefficient;

-         data.green_to_set = data.green_coefficient;

-#     else

-         data.red_to_set = fix(data.red_coefficient);

-         data.green_to_set = fix(data.green_coefficient);

-#     endif

-

-      /* The following just changes the error messages: */

-      pm->encoding_ignored = 1;

-   }

-

-   else

-   {

-      data.red_to_set = -1;

-      data.green_to_set = -1;

-   }

-

-   /* Adjust the error limit in the png_modifier because of the larger errors

-    * produced in the digitization during the gamma handling.

-    */

-   if (data.gamma != 1) /* Use gamma tables */

-   {

-      if (that->this.bit_depth == 16 || pm->assume_16_bit_calculations)

-      {

-         /* The 16 bit case ends up producing a maximum error of about

-          * +/-5 in 65535, allow for +/-8 with the given gamma.

-          */

-         that->pm->limit += pow(8./65535, data.gamma);

-      }

-

-      else

-      {

-         /* Rounding to 8 bits in the linear space causes massive errors which

-          * will trigger the error check in transform_range_check.  Fix that

-          * here by taking the gamma encoding into account.

-          */

-         that->pm->limit += pow(1./255, data.gamma);

-      }

-   }

-

-   else

-   {

-      /* With no gamma correction a large error comes from the truncation of the

-       * calculation in the 8 bit case, allow for that here.

-       */

-      if (that->this.bit_depth != 16)

-         that->pm->limit += 4E-3;

-   }

-}

-

-static void

-image_transform_png_set_rgb_to_gray_set(PNG_CONST image_transform *this,

-    transform_display *that, png_structp pp, png_infop pi)

-{

-   PNG_CONST int error_action = 1; /* no error, no defines in png.h */

-

-#  ifdef PNG_FLOATING_POINT_SUPPORTED

-      png_set_rgb_to_gray(pp, error_action, data.red_to_set, data.green_to_set);

-#  else

-      png_set_rgb_to_gray_fixed(pp, error_action, data.red_to_set,

-         data.green_to_set);

-#  endif

-

-#  ifdef PNG_READ_cHRM_SUPPORTED

-      if (that->pm->current_encoding != 0)

-      {

-         /* We have an encoding so a cHRM chunk may have been set; if so then

-          * check that the libpng APIs give the correct (X,Y,Z) values within

-          * some margin of error for the round trip through the chromaticity

-          * form.

-          */

-#        ifdef PNG_FLOATING_POINT_SUPPORTED

-#           define API_function png_get_cHRM_XYZ

-#           define API_form "FP"

-#           define API_type double

-#           define API_cvt(x) (x)

-#        else

-#           define API_function png_get_cHRM_XYZ_fixed

-#           define API_form "fixed"

-#           define API_type png_fixed_point

-#           define API_cvt(x) ((double)(x)/PNG_FP_1)

-#        endif

-

-         API_type rX, gX, bX;

-         API_type rY, gY, bY;

-         API_type rZ, gZ, bZ;

-

-         if ((API_function(pp, pi, &rX, &rY, &rZ, &gX, &gY, &gZ, &bX, &bY, &bZ)

-               & PNG_INFO_cHRM) != 0)

-         {

-            double maxe;

-            PNG_CONST char *el;

-            color_encoding e, o;

-

-            /* Expect libpng to return a normalized result, but the original

-             * color space encoding may not be normalized.

-             */

-            modifier_current_encoding(that->pm, &o);

-            normalize_color_encoding(&o);

-

-            /* Sanity check the pngvalid code - the coefficients should match

-             * the normalized Y values of the encoding unless they were

-             * overridden.

-             */

-            if (data.red_to_set == -1 && data.green_to_set == -1 &&

-               (fabs(o.red.Y - data.red_coefficient) > DBL_EPSILON ||

-               fabs(o.green.Y - data.green_coefficient) > DBL_EPSILON ||

-               fabs(o.blue.Y - data.blue_coefficient) > DBL_EPSILON))

-               png_error(pp, "internal pngvalid cHRM coefficient error");

-

-            /* Generate a colour space encoding. */

-            e.gamma = o.gamma; /* not used */

-            e.red.X = API_cvt(rX);

-            e.red.Y = API_cvt(rY);

-            e.red.Z = API_cvt(rZ);

-            e.green.X = API_cvt(gX);

-            e.green.Y = API_cvt(gY);

-            e.green.Z = API_cvt(gZ);

-            e.blue.X = API_cvt(bX);

-            e.blue.Y = API_cvt(bY);

-            e.blue.Z = API_cvt(bZ);

-

-            /* This should match the original one from the png_modifier, within

-             * the range permitted by the libpng fixed point representation.

-             */

-            maxe = 0;

-            el = "-"; /* Set to element name with error */

-

-#           define CHECK(col,x)\

-            {\

-               double err = fabs(o.col.x - e.col.x);\

-               if (err > maxe)\

-               {\

-                  maxe = err;\

-                  el = #col "(" #x ")";\

-               }\

-            }

-

-            CHECK(red,X)

-            CHECK(red,Y)

-            CHECK(red,Z)

-            CHECK(green,X)

-            CHECK(green,Y)

-            CHECK(green,Z)

-            CHECK(blue,X)

-            CHECK(blue,Y)

-            CHECK(blue,Z)

-

-            /* Here in both fixed and floating cases to check the values read

-             * from the cHRm chunk.  PNG uses fixed point in the cHRM chunk, so

-             * we can't expect better than +/-.5E-5 on the result, allow 1E-5.

-             */

-            if (maxe >= 1E-5)

-            {

-               size_t pos = 0;

-               char buffer[256];

-

-               pos = safecat(buffer, sizeof buffer, pos, API_form);

-               pos = safecat(buffer, sizeof buffer, pos, " cHRM ");

-               pos = safecat(buffer, sizeof buffer, pos, el);

-               pos = safecat(buffer, sizeof buffer, pos, " error: ");

-               pos = safecatd(buffer, sizeof buffer, pos, maxe, 7);

-               pos = safecat(buffer, sizeof buffer, pos, " ");

-               /* Print the color space without the gamma value: */

-               pos = safecat_color_encoding(buffer, sizeof buffer, pos, &o, 0);

-               pos = safecat(buffer, sizeof buffer, pos, " -> ");

-               pos = safecat_color_encoding(buffer, sizeof buffer, pos, &e, 0);

-

-               png_error(pp, buffer);

-            }

-         }

-      }

-#  endif /* READ_cHRM */

-

-   this->next->set(this->next, that, pp, pi);

-}

-

-static void

-image_transform_png_set_rgb_to_gray_mod(PNG_CONST image_transform *this,

-    image_pixel *that, png_structp pp, PNG_CONST transform_display *display)

-{

-   if ((that->colour_type & PNG_COLOR_MASK_COLOR) != 0)

-   {

-      double gray, err;

-

-      if (that->colour_type == PNG_COLOR_TYPE_PALETTE)

-         image_pixel_convert_PLTE(that);

-

-      /* Image now has RGB channels... */

-      {

-         PNG_CONST png_modifier *pm = display->pm;

-         PNG_CONST unsigned int sample_depth = that->sample_depth;

-         int isgray;

-         double r, g, b;

-         double rlo, rhi, glo, ghi, blo, bhi, graylo, grayhi;

-

-         /* Do this using interval arithmetic, otherwise it is too difficult to

-          * handle the errors correctly.

-          *

-          * To handle the gamma correction work out the upper and lower bounds

-          * of the digitized value.  Assume rounding here - normally the values

-          * will be identical after this operation if there is only one

-          * transform, feel free to delete the png_error checks on this below in

-          * the future (this is just me trying to ensure it works!)

-          */

-         r = rlo = rhi = that->redf;

-         rlo -= that->rede;

-         rlo = digitize(pm, rlo, sample_depth, 1/*round*/);

-         rhi += that->rede;

-         rhi = digitize(pm, rhi, sample_depth, 1/*round*/);

-

-         g = glo = ghi = that->greenf;

-         glo -= that->greene;

-         glo = digitize(pm, glo, sample_depth, 1/*round*/);

-         ghi += that->greene;

-         ghi = digitize(pm, ghi, sample_depth, 1/*round*/);

-

-         b = blo = bhi = that->bluef;

-         blo -= that->bluee;

-         blo = digitize(pm, blo, sample_depth, 1/*round*/);

-         bhi += that->greene;

-         bhi = digitize(pm, bhi, sample_depth, 1/*round*/);

-

-         isgray = r==g && g==b;

-

-         if (data.gamma != 1)

-         {

-            PNG_CONST double power = 1/data.gamma;

-            PNG_CONST double abse = abserr(pm, sample_depth, sample_depth);

-

-            /* 'abse' is the absolute error permitted in linear calculations. It

-             * is used here to capture the error permitted in the handling

-             * (undoing) of the gamma encoding.  Once again digitization occurs

-             * to handle the upper and lower bounds of the values.  This is

-             * where the real errors are introduced.

-             */

-            r = pow(r, power);

-            rlo = digitize(pm, pow(rlo, power)-abse, sample_depth, 1);

-            rhi = digitize(pm, pow(rhi, power)+abse, sample_depth, 1);

-

-            g = pow(g, power);

-            glo = digitize(pm, pow(glo, power)-abse, sample_depth, 1);

-            ghi = digitize(pm, pow(ghi, power)+abse, sample_depth, 1);

-

-            b = pow(b, power);

-            blo = digitize(pm, pow(blo, power)-abse, sample_depth, 1);

-            bhi = digitize(pm, pow(bhi, power)+abse, sample_depth, 1);

-         }

-

-         /* Now calculate the actual gray values.  Although the error in the

-          * coefficients depends on whether they were specified on the command

-          * line (in which case truncation to 15 bits happened) or not (rounding

-          * was used) the maxium error in an individual coefficient is always

-          * 1/32768, because even in the rounding case the requirement that

-          * coefficients add up to 32768 can cause a larger rounding error.

-          *

-          * The only time when rounding doesn't occur in 1.5.5 and later is when

-          * the non-gamma code path is used for less than 16 bit data.

-          */

-         gray = r * data.red_coefficient + g * data.green_coefficient +

-            b * data.blue_coefficient;

-

-         {

-            PNG_CONST int do_round = data.gamma != 1 || sample_depth == 16;

-            PNG_CONST double ce = 1. / 32768;

-

-            graylo = digitize(pm, rlo * (data.red_coefficient-ce) +

-               glo * (data.green_coefficient-ce) +

-               blo * (data.blue_coefficient-ce), sample_depth, do_round);

-            if (graylo <= 0)

-               graylo = 0;

-

-            grayhi = digitize(pm, rhi * (data.red_coefficient+ce) +

-               ghi * (data.green_coefficient+ce) +

-               bhi * (data.blue_coefficient+ce), sample_depth, do_round);

-            if (grayhi >= 1)

-               grayhi = 1;

-         }

-

-         /* And invert the gamma. */

-         if (data.gamma != 1)

-         {

-            PNG_CONST double power = data.gamma;

-

-            gray = pow(gray, power);

-            graylo = digitize(pm, pow(graylo, power), sample_depth, 1);

-            grayhi = digitize(pm, pow(grayhi, power), sample_depth, 1);

-         }

-

-         /* Now the error can be calculated.

-          *

-          * If r==g==b because there is no overall gamma correction libpng

-          * currently preserves the original value.

-          */

-         if (isgray)

-            err = (that->rede + that->greene + that->bluee)/3;

-

-         else

-         {

-            err = fabs(grayhi-gray);

-            if (fabs(gray - graylo) > err)

-               err = fabs(graylo-gray);

-

-            /* Check that this worked: */

-            if (err > display->pm->limit)

-            {

-               size_t pos = 0;

-               char buffer[128];

-

-               pos = safecat(buffer, sizeof buffer, pos, "rgb_to_gray error ");

-               pos = safecatd(buffer, sizeof buffer, pos, err, 6);

-               pos = safecat(buffer, sizeof buffer, pos, " exceeds limit ");

-               pos = safecatd(buffer, sizeof buffer, pos,

-                  display->pm->limit, 6);

-               png_error(pp, buffer);

-            }

-         }

-      }

-

-      that->bluef = that->greenf = that->redf = gray;

-      that->bluee = that->greene = that->rede = err;

-

-      /* The sBIT is the minium of the three colour channel sBITs. */

-      if (that->red_sBIT > that->green_sBIT)

-         that->red_sBIT = that->green_sBIT;

-      if (that->red_sBIT > that->blue_sBIT)

-         that->red_sBIT = that->blue_sBIT;

-      that->blue_sBIT = that->green_sBIT = that->red_sBIT;

-

-      /* And remove the colour bit in the type: */

-      if (that->colour_type == PNG_COLOR_TYPE_RGB)

-         that->colour_type = PNG_COLOR_TYPE_GRAY;

-      else if (that->colour_type == PNG_COLOR_TYPE_RGB_ALPHA)

-         that->colour_type = PNG_COLOR_TYPE_GRAY_ALPHA;

-   }

-

-   this->next->mod(this->next, that, pp, display);

-}

-

-static int

-image_transform_png_set_rgb_to_gray_add(image_transform *this,

-    PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth)

-{

-   UNUSED(bit_depth)

-

-   this->next = *that;

-   *that = this;

-

-   return (colour_type & PNG_COLOR_MASK_COLOR) != 0;

-}

-

-#undef data

-IT(rgb_to_gray);

-#undef PT

-#define PT ITSTRUCT(rgb_to_gray)

-#undef image_transform_ini

-#define image_transform_ini image_transform_default_ini

-#endif /* PNG_READ_RGB_TO_GRAY_SUPPORTED */

-

-#ifdef PNG_READ_BACKGROUND_SUPPORTED

-/* png_set_background(png_structp, png_const_color_16p background_color,

- *    int background_gamma_code, int need_expand, double background_gamma)

- * png_set_background_fixed(png_structp, png_const_color_16p background_color,

- *    int background_gamma_code, int need_expand,

- *    png_fixed_point background_gamma)

- *

- * As with rgb_to_gray this ignores the gamma (at present.)

-*/

-#define data ITDATA(background)

-static image_pixel data;

-

-static void

-image_transform_png_set_background_set(PNG_CONST image_transform *this,

-    transform_display *that, png_structp pp, png_infop pi)

-{

-   png_byte colour_type, bit_depth;

-   png_byte random_bytes[8]; /* 8 bytes - 64 bits - the biggest pixel */

-   png_color_16 back;

-

-   /* We need a background colour, because we don't know exactly what transforms

-    * have been set we have to supply the colour in the original file format and

-    * so we need to know what that is!  The background colour is stored in the

-    * transform_display.

-    */

-   RANDOMIZE(random_bytes);

-

-   /* Read the random value, for colour type 3 the background colour is actually

-    * expressed as a 24bit rgb, not an index.

-    */

-   colour_type = that->this.colour_type;

-   if (colour_type == 3)

-   {

-      colour_type = PNG_COLOR_TYPE_RGB;

-      bit_depth = 8;

-   }

-

-   else

-      bit_depth = that->this.bit_depth;

-

-   image_pixel_init(&data, random_bytes, colour_type,

-      bit_depth, 0/*x*/, 0/*unused: palette*/);

-

-   /* Extract the background colour from this image_pixel, but make sure the

-    * unused fields of 'back' are garbage.

-    */

-   RANDOMIZE(back);

-

-   if (colour_type & PNG_COLOR_MASK_COLOR)

-   {

-      back.red = (png_uint_16)data.red;

-      back.green = (png_uint_16)data.green;

-      back.blue = (png_uint_16)data.blue;

-   }

-

-   else

-      back.gray = (png_uint_16)data.red;

-

-#  ifdef PNG_FLOATING_POINT_SUPPORTED

-      png_set_background(pp, &back, PNG_BACKGROUND_GAMMA_FILE, 1/*need expand*/,

-         0);

-#  else

-      png_set_background_fixed(pp, &back, PNG_BACKGROUND_GAMMA_FILE,

-         1/*need expand*/, 0);

-#  endif

-

-   this->next->set(this->next, that, pp, pi);

-}

-

-static void

-image_transform_png_set_background_mod(PNG_CONST image_transform *this,

-    image_pixel *that, png_structp pp, PNG_CONST transform_display *display)

-{

-   /* Check for tRNS first: */

-   if (that->have_tRNS && that->colour_type != PNG_COLOR_TYPE_PALETTE)

-      image_pixel_add_alpha(that, &display->this);

-

-   /* This is only necessary if the alpha value is less than 1. */

-   if (that->alphaf < 1)

-   {

-      /* Now we do the background calculation without any gamma correction. */

-      if (that->alphaf <= 0)

-      {

-         that->redf = data.redf;

-         that->greenf = data.greenf;

-         that->bluef = data.bluef;

-

-         that->rede = data.rede;

-         that->greene = data.greene;

-         that->bluee = data.bluee;

-

-         that->red_sBIT= data.red_sBIT;

-         that->green_sBIT= data.green_sBIT;

-         that->blue_sBIT= data.blue_sBIT;

-      }

-

-      else /* 0 < alpha < 1 */

-      {

-         double alf = 1 - that->alphaf;

-

-         that->redf = that->redf * that->alphaf + data.redf * alf;

-         that->rede = that->rede * that->alphaf + data.rede * alf +

-            DBL_EPSILON;

-         that->greenf = that->greenf * that->alphaf + data.greenf * alf;

-         that->greene = that->greene * that->alphaf + data.greene * alf +

-            DBL_EPSILON;

-         that->bluef = that->bluef * that->alphaf + data.bluef * alf;

-         that->bluee = that->bluee * that->alphaf + data.bluee * alf +

-            DBL_EPSILON;

-      }

-

-      /* Remove the alpha type and set the alpha (not in that order.) */

-      that->alphaf = 1;

-      that->alphae = 0;

-

-      if (that->colour_type == PNG_COLOR_TYPE_RGB_ALPHA)

-         that->colour_type = PNG_COLOR_TYPE_RGB;

-      else if (that->colour_type == PNG_COLOR_TYPE_GRAY_ALPHA)

-         that->colour_type = PNG_COLOR_TYPE_GRAY;

-      /* PNG_COLOR_TYPE_PALETTE is not changed */

-   }

-

-   this->next->mod(this->next, that, pp, display);

-}

-

-#define image_transform_png_set_background_add image_transform_default_add

-

-#undef data

-IT(background);

-#undef PT

-#define PT ITSTRUCT(background)

-#endif /* PNG_READ_BACKGROUND_SUPPORTED */

-

-/* This may just be 'end' if all the transforms are disabled! */

-static image_transform *PNG_CONST image_transform_first = &PT;

-

-static void

-transform_enable(PNG_CONST char *name)

-{

-   /* Everything starts out enabled, so if we see an 'enable' disabled

-    * everything else the first time round.

-    */

-   static int all_disabled = 0;

-   int found_it = 0;

-   image_transform *list = image_transform_first;

-

-   while (list != &image_transform_end)

-   {

-      if (strcmp(list->name, name) == 0)

-      {

-         list->enable = 1;

-         found_it = 1;

-      }

-      else if (!all_disabled)

-         list->enable = 0;

-

-      list = list->list;

-   }

-

-   all_disabled = 1;

-

-   if (!found_it)

-   {

-      fprintf(stderr, "pngvalid: --transform-enable=%s: unknown transform\n",

-         name);

-      exit(1);

-   }

-}

-

-static void

-transform_disable(PNG_CONST char *name)

-{

-   image_transform *list = image_transform_first;

-

-   while (list != &image_transform_end)

-   {

-      if (strcmp(list->name, name) == 0)

-      {

-         list->enable = 0;

-         return;

-      }

-

-      list = list->list;

-   }

-

-   fprintf(stderr, "pngvalid: --transform-disable=%s: unknown transform\n",

-      name);

-   exit(1);

-}

-

-static void

-image_transform_reset_count(void)

-{

-   image_transform *next = image_transform_first;

-   int count = 0;

-

-   while (next != &image_transform_end)

-   {

-      next->local_use = 0;

-      next->next = 0;

-      next = next->list;

-      ++count;

-   }

-

-   /* This can only happen if we every have more than 32 transforms (excluding

-    * the end) in the list.

-    */

-   if (count > 32) abort();

-}

-

-static int

-image_transform_test_counter(png_uint_32 counter, unsigned int max)

-{

-   /* Test the list to see if there is any point contining, given a current

-    * counter and a 'max' value.

-    */

-   image_transform *next = image_transform_first;

-

-   while (next != &image_transform_end)

-   {

-      /* For max 0 or 1 continue until the counter overflows: */

-      counter >>= 1;

-

-      /* Continue if any entry hasn't reacked the max. */

-      if (max > 1 && next->local_use < max)

-         return 1;

-      next = next->list;

-   }

-

-   return max <= 1 && counter == 0;

-}

-

-static png_uint_32

-image_transform_add(PNG_CONST image_transform **this, unsigned int max,

-   png_uint_32 counter, char *name, size_t sizeof_name, size_t *pos,

-   png_byte colour_type, png_byte bit_depth)

-{

-   for (;;) /* until we manage to add something */

-   {

-      png_uint_32 mask;

-      image_transform *list;

-

-      /* Find the next counter value, if the counter is zero this is the start

-       * of the list.  This routine always returns the current counter (not the

-       * next) so it returns 0 at the end and expects 0 at the beginning.

-       */

-      if (counter == 0) /* first time */

-      {

-         image_transform_reset_count();

-         if (max <= 1)

-            counter = 1;

-         else

-            counter = random_32();

-      }

-      else /* advance the counter */

-      {

-         switch (max)

-         {

-            case 0:  ++counter; break;

-            case 1:  counter <<= 1; break;

-            default: counter = random_32(); break;

-         }

-      }

-

-      /* Now add all these items, if possible */

-      *this = &image_transform_end;

-      list = image_transform_first;

-      mask = 1;

-

-      /* Go through the whole list adding anything that the counter selects: */

-      while (list != &image_transform_end)

-      {

-         if ((counter & mask) != 0 && list->enable &&

-             (max == 0 || list->local_use < max))

-         {

-            /* Candidate to add: */

-            if (list->add(list, this, colour_type, bit_depth) || max == 0)

-            {

-               /* Added, so add to the name too. */

-               *pos = safecat(name, sizeof_name, *pos, " +");

-               *pos = safecat(name, sizeof_name, *pos, list->name);

-            }

-

-            else

-            {

-               /* Not useful and max>0, so remove it from *this: */

-               *this = list->next;

-               list->next = 0;

-

-               /* And, since we know it isn't useful, stop it being added again

-                * in this run:

-                */

-               list->local_use = max;

-            }

-         }

-

-         mask <<= 1;

-         list = list->list;

-      }

-

-      /* Now if anything was added we have something to do. */

-      if (*this != &image_transform_end)

-         return counter;

-

-      /* Nothing added, but was there anything in there to add? */

-      if (!image_transform_test_counter(counter, max))

-         return 0;

-   }

-}

-

-#ifdef THIS_IS_THE_PROFORMA

-static void

-image_transform_png_set_@_set(PNG_CONST image_transform *this,

-    transform_display *that, png_structp pp, png_infop pi)

-{

-   png_set_@(pp);

-   this->next->set(this->next, that, pp, pi);

-}

-

-static void

-image_transform_png_set_@_mod(PNG_CONST image_transform *this,

-    image_pixel *that, png_structp pp, PNG_CONST transform_display *display)

-{

-   this->next->mod(this->next, that, pp, display);

-}

-

-static int

-image_transform_png_set_@_add(image_transform *this,

-    PNG_CONST image_transform **that, char *name, size_t sizeof_name,

-    size_t *pos, png_byte colour_type, png_byte bit_depth)

-{

-   this->next = *that;

-   *that = this;

-

-   *pos = safecat(name, sizeof_name, *pos, " +@");

-

-   return 1;

-}

-

-IT(@);

-#endif

-

-/* png_set_quantize(png_structp, png_colorp palette, int num_palette,

- *    int maximum_colors, png_const_uint_16p histogram, int full_quantize)

- *

- * Very difficult to validate this!

- */

-/*NOTE: TBD NYI */

-

-/* The data layout transforms are handled by swapping our own channel data,

- * necessarily these need to happen at the end of the transform list because the

- * semantic of the channels changes after these are executed.  Some of these,

- * like set_shift and set_packing, can't be done at present because they change

- * the layout of the data at the sub-sample level so sample() won't get the

- * right answer.

- */

-/* png_set_invert_alpha */

-/*NOTE: TBD NYI */

-

-/* png_set_bgr */

-/*NOTE: TBD NYI */

-

-/* png_set_swap_alpha */

-/*NOTE: TBD NYI */

-

-/* png_set_swap */

-/*NOTE: TBD NYI */

-

-/* png_set_filler, (png_structp png_ptr, png_uint_32 filler, int flags)); */

-/*NOTE: TBD NYI */

-

-/* png_set_add_alpha, (png_structp png_ptr, png_uint_32 filler, int flags)); */

-/*NOTE: TBD NYI */

-

-/* png_set_packing */

-/*NOTE: TBD NYI */

-

-/* png_set_packswap */

-/*NOTE: TBD NYI */

-

-/* png_set_invert_mono */

-/*NOTE: TBD NYI */

-

-/* png_set_shift(png_structp, png_const_color_8p true_bits) */

-/*NOTE: TBD NYI */

-

-static void

-perform_transform_test(png_modifier *pm)

-{

-   png_byte colour_type = 0;

-   png_byte bit_depth = 0;

-   int palette_number = 0;

-

-   while (next_format(&colour_type, &bit_depth, &palette_number))

-   {

-      png_uint_32 counter = 0;

-      size_t base_pos;

-      char name[64];

-

-      base_pos = safecat(name, sizeof name, 0, "transform:");

-

-      for (;;)

-      {

-         size_t pos = base_pos;

-         PNG_CONST image_transform *list = 0;

-

-         /* 'max' is currently hardwired to '1'; this should be settable on the

-          * command line.

-          */

-         counter = image_transform_add(&list, 1/*max*/, counter,

-            name, sizeof name, &pos, colour_type, bit_depth);

-

-         if (counter == 0)

-            break;

-

-         /* The command line can change this to checking interlaced images. */

-         do

-         {

-            pm->repeat = 0;

-            transform_test(pm, FILEID(colour_type, bit_depth, palette_number,

-               pm->interlace_type, 0, 0, 0), list, name);

-

-            if (fail(pm))

-               return;

-         }

-         while (pm->repeat);

-      }

-   }

-}

-#endif /* PNG_READ_TRANSFORMS_SUPPORTED */

-

-/********************************* GAMMA TESTS ********************************/

-#ifdef PNG_READ_GAMMA_SUPPORTED

-/* Reader callbacks and implementations, where they differ from the standard

- * ones.

- */

-typedef struct gamma_display

-{

-   standard_display this;

-

-   /* Parameters */

-   png_modifier*    pm;

-   double           file_gamma;

-   double           screen_gamma;

-   double           background_gamma;

-   png_byte         sbit;

-   int              threshold_test;

-   int              use_input_precision;

-   int              scale16;

-   int              expand16;

-   int              do_background;

-   png_color_16     background_color;

-

-   /* Local variables */

-   double       maxerrout;

-   double       maxerrpc;

-   double       maxerrabs;

-} gamma_display;

-

-#define ALPHA_MODE_OFFSET 4

-

-static void

-gamma_display_init(gamma_display *dp, png_modifier *pm, png_uint_32 id,

-    double file_gamma, double screen_gamma, png_byte sbit, int threshold_test,

-    int use_input_precision, int scale16, int expand16,

-    int do_background, PNG_CONST png_color_16 *pointer_to_the_background_color,

-    double background_gamma)

-{

-   /* Standard fields */

-   standard_display_init(&dp->this, &pm->this, id, 0/*do_interlace*/,

-      pm->use_update_info);

-

-   /* Parameter fields */

-   dp->pm = pm;

-   dp->file_gamma = file_gamma;

-   dp->screen_gamma = screen_gamma;

-   dp->background_gamma = background_gamma;

-   dp->sbit = sbit;

-   dp->threshold_test = threshold_test;

-   dp->use_input_precision = use_input_precision;

-   dp->scale16 = scale16;

-   dp->expand16 = expand16;

-   dp->do_background = do_background;

-   if (do_background && pointer_to_the_background_color != 0)

-      dp->background_color = *pointer_to_the_background_color;

-   else

-      memset(&dp->background_color, 0, sizeof dp->background_color);

-

-   /* Local variable fields */

-   dp->maxerrout = dp->maxerrpc = dp->maxerrabs = 0;

-}

-

-static void

-gamma_info_imp(gamma_display *dp, png_structp pp, png_infop pi)

-{

-   /* Reuse the standard stuff as appropriate. */

-   standard_info_part1(&dp->this, pp, pi);

-

-   /* If requested strip 16 to 8 bits - this is handled automagically below

-    * because the output bit depth is read from the library.  Note that there

-    * are interactions with sBIT but, internally, libpng makes sbit at most

-    * PNG_MAX_GAMMA_8 when doing the following.

-    */

-   if (dp->scale16)

-#     ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED

-         png_set_scale_16(pp);

-#     else

-         /* The following works both in 1.5.4 and earlier versions: */

-#        ifdef PNG_READ_16_TO_8_SUPPORTED

-            png_set_strip_16(pp);

-#        else

-            png_error(pp, "scale16 (16 to 8 bit conversion) not supported");

-#        endif

-#     endif

-

-   if (dp->expand16)

-#     ifdef PNG_READ_EXPAND_16_SUPPORTED

-         png_set_expand_16(pp);

-#     else

-         png_error(pp, "expand16 (8 to 16 bit conversion) not supported");

-#     endif

-

-   if (dp->do_background >= ALPHA_MODE_OFFSET)

-   {

-#     ifdef PNG_READ_ALPHA_MODE_SUPPORTED

-      {

-         /* This tests the alpha mode handling, if supported. */

-         int mode = dp->do_background - ALPHA_MODE_OFFSET;

-

-         /* The gamma value is the output gamma, and is in the standard,

-          * non-inverted, represenation.  It provides a default for the PNG file

-          * gamma, but since the file has a gAMA chunk this does not matter.

-          */

-         PNG_CONST double sg = dp->screen_gamma;

-#        ifndef PNG_FLOATING_POINT_SUPPORTED

-            PNG_CONST png_fixed_point g = fix(sg);

-#        endif

-

-#        ifdef PNG_FLOATING_POINT_SUPPORTED

-            png_set_alpha_mode(pp, mode, sg);

-#        else

-            png_set_alpha_mode_fixed(pp, mode, g);

-#        endif

-

-         /* However, for the standard Porter-Duff algorithm the output defaults

-          * to be linear, so if the test requires non-linear output it must be

-          * corrected here.

-          */

-         if (mode == PNG_ALPHA_STANDARD && sg != 1)

-         {

-#           ifdef PNG_FLOATING_POINT_SUPPORTED

-               png_set_gamma(pp, sg, dp->file_gamma);

-#           else

-               png_fixed_point f = fix(dp->file_gamma);

-               png_set_gamma_fixed(pp, g, f);

-#           endif

-         }

-      }

-#     else

-         png_error(pp, "alpha mode handling not supported");

-#     endif

-   }

-

-   else

-   {

-      /* Set up gamma processing. */

-#     ifdef PNG_FLOATING_POINT_SUPPORTED

-         png_set_gamma(pp, dp->screen_gamma, dp->file_gamma);

-#     else

-      {

-         png_fixed_point s = fix(dp->screen_gamma);

-         png_fixed_point f = fix(dp->file_gamma);

-         png_set_gamma_fixed(pp, s, f);

-      }

-#     endif

-

-      if (dp->do_background)

-      {

-#     ifdef PNG_READ_BACKGROUND_SUPPORTED

-         /* NOTE: this assumes the caller provided the correct background gamma!

-          */

-         PNG_CONST double bg = dp->background_gamma;

-#        ifndef PNG_FLOATING_POINT_SUPPORTED

-            PNG_CONST png_fixed_point g = fix(bg);

-#        endif

-

-#        ifdef PNG_FLOATING_POINT_SUPPORTED

-            png_set_background(pp, &dp->background_color, dp->do_background,

-               0/*need_expand*/, bg);

-#        else

-            png_set_background_fixed(pp, &dp->background_color,

-               dp->do_background, 0/*need_expand*/, g);

-#        endif

-#     else

-         png_error(pp, "png_set_background not supported");

-#     endif

-      }

-   }

-

-   {

-      int i = dp->this.use_update_info;

-      /* Always do one call, even if use_update_info is 0. */

-      do

-         png_read_update_info(pp, pi);

-      while (--i > 0);

-   }

-

-   /* Now we may get a different cbRow: */

-   standard_info_part2(&dp->this, pp, pi, 1 /*images*/);

-}

-

-static void

-gamma_info(png_structp pp, png_infop pi)

-{

-   gamma_info_imp(voidcast(gamma_display*, png_get_progressive_ptr(pp)), pp,

-      pi);

-}

-

-/* Validate a single component value - the routine gets the input and output

- * sample values as unscaled PNG component values along with a cache of all the

- * information required to validate the values.

- */

-typedef struct validate_info

-{

-   png_structp  pp;

-   gamma_display *dp;

-   png_byte sbit;

-   int use_input_precision;

-   int do_background;

-   int scale16;

-   unsigned int sbit_max;

-   unsigned int isbit_shift;

-   unsigned int outmax;

-

-   double gamma_correction; /* Overall correction required. */

-   double file_inverse;     /* Inverse of file gamma. */

-   double screen_gamma;

-   double screen_inverse;   /* Inverse of screen gamma. */

-

-   double background_red;   /* Linear background value, red or gray. */

-   double background_green;

-   double background_blue;

-

-   double maxabs;

-   double maxpc;

-   double maxcalc;

-   double maxout;

-   double maxout_total;     /* Total including quantization error */

-   double outlog;

-   int    outquant;

-}

-validate_info;

-

-static void

-init_validate_info(validate_info *vi, gamma_display *dp, png_struct *pp,

-    int in_depth, int out_depth)

-{

-   PNG_CONST unsigned int outmax = (1U<<out_depth)-1;

-

-   vi->pp = pp;

-   vi->dp = dp;

-

-   if (dp->sbit > 0 && dp->sbit < in_depth)

-   {

-      vi->sbit = dp->sbit;

-      vi->isbit_shift = in_depth - dp->sbit;

-   }

-

-   else

-   {

-      vi->sbit = (png_byte)in_depth;

-      vi->isbit_shift = 0;

-   }

-

-   vi->sbit_max = (1U << vi->sbit)-1;

-

-   /* This mimics the libpng threshold test, '0' is used to prevent gamma

-    * correction in the validation test.

-    */

-   vi->screen_gamma = dp->screen_gamma;

-   if (fabs(vi->screen_gamma-1) < PNG_GAMMA_THRESHOLD)

-      vi->screen_gamma = vi->screen_inverse = 0;

-   else

-      vi->screen_inverse = 1/vi->screen_gamma;

-

-   vi->use_input_precision = dp->use_input_precision;

-   vi->outmax = outmax;

-   vi->maxabs = abserr(dp->pm, in_depth, out_depth);

-   vi->maxpc = pcerr(dp->pm, in_depth, out_depth);

-   vi->maxcalc = calcerr(dp->pm, in_depth, out_depth);

-   vi->maxout = outerr(dp->pm, in_depth, out_depth);

-   vi->outquant = output_quantization_factor(dp->pm, in_depth, out_depth);

-   vi->maxout_total = vi->maxout + vi->outquant * .5;

-   vi->outlog = outlog(dp->pm, in_depth, out_depth);

-

-   if ((dp->this.colour_type & PNG_COLOR_MASK_ALPHA) != 0 ||

-      (dp->this.colour_type == 3 && dp->this.is_transparent))

-   {

-      vi->do_background = dp->do_background;

-

-      if (vi->do_background != 0)

-      {

-         PNG_CONST double bg_inverse = 1/dp->background_gamma;

-         double r, g, b;

-

-         /* Caller must at least put the gray value into the red channel */

-         r = dp->background_color.red; r /= outmax;

-         g = dp->background_color.green; g /= outmax;

-         b = dp->background_color.blue; b /= outmax;

-

-#     if 0

-         /* libpng doesn't do this optimization, if we do pngvalid will fail.

-          */

-         if (fabs(bg_inverse-1) >= PNG_GAMMA_THRESHOLD)

-#     endif

-         {

-            r = pow(r, bg_inverse);

-            g = pow(g, bg_inverse);

-            b = pow(b, bg_inverse);

-         }

-

-         vi->background_red = r;

-         vi->background_green = g;

-         vi->background_blue = b;

-      }

-   }

-   else

-      vi->do_background = 0;

-

-   if (vi->do_background == 0)

-      vi->background_red = vi->background_green = vi->background_blue = 0;

-

-   vi->gamma_correction = 1/(dp->file_gamma*dp->screen_gamma);

-   if (fabs(vi->gamma_correction-1) < PNG_GAMMA_THRESHOLD)

-      vi->gamma_correction = 0;

-

-   vi->file_inverse = 1/dp->file_gamma;

-   if (fabs(vi->file_inverse-1) < PNG_GAMMA_THRESHOLD)

-      vi->file_inverse = 0;

-

-   vi->scale16 = dp->scale16;

-}

-

-/* This function handles composition of a single non-alpha component.  The

- * argument is the input sample value, in the range 0..1, and the alpha value.

- * The result is the composed, linear, input sample.  If alpha is less than zero

- * this is the alpha component and the function should not be called!

- */

-static double

-gamma_component_compose(int do_background, double input_sample, double alpha,

-   double background, int *compose)

-{

-   switch (do_background)

-   {

-      case PNG_BACKGROUND_GAMMA_SCREEN:

-      case PNG_BACKGROUND_GAMMA_FILE:

-      case PNG_BACKGROUND_GAMMA_UNIQUE:

-         /* Standard PNG background processing. */

-         if (alpha < 1)

-         {

-            if (alpha > 0)

-            {

-               input_sample = input_sample * alpha + background * (1-alpha);

-               if (compose != NULL)

-                  *compose = 1;

-            }

-

-            else

-               input_sample = background;

-         }

-         break;

-

-#ifdef PNG_READ_ALPHA_MODE_SUPPORTED

-      case ALPHA_MODE_OFFSET + PNG_ALPHA_STANDARD:

-      case ALPHA_MODE_OFFSET + PNG_ALPHA_BROKEN:

-         /* The components are premultiplied in either case and the output is

-          * gamma encoded (to get standard Porter-Duff we expect the output

-          * gamma to be set to 1.0!)

-          */

-      case ALPHA_MODE_OFFSET + PNG_ALPHA_OPTIMIZED:

-         /* The optimization is that the partial-alpha entries are linear

-          * while the opaque pixels are gamma encoded, but this only affects the

-          * output encoding.

-          */

-         if (alpha < 1)

-         {

-            if (alpha > 0)

-            {

-               input_sample *= alpha;

-               if (compose != NULL)

-                  *compose = 1;

-            }

-

-            else

-               input_sample = 0;

-         }

-         break;

-#endif

-

-      default:

-         /* Standard cases where no compositing is done (so the component

-          * value is already correct.)

-          */

-         break;

-   }

-

-   return input_sample;

-}

-

-/* This API returns the encoded *input* component, in the range 0..1 */

-static double

-gamma_component_validate(PNG_CONST char *name, PNG_CONST validate_info *vi,

-    PNG_CONST unsigned int id, PNG_CONST unsigned int od,

-    PNG_CONST double alpha /* <0 for the alpha channel itself */,

-    PNG_CONST double background /* component background value */)

-{

-   PNG_CONST unsigned int isbit = id >> vi->isbit_shift;

-   PNG_CONST unsigned int sbit_max = vi->sbit_max;

-   PNG_CONST unsigned int outmax = vi->outmax;

-   PNG_CONST int do_background = vi->do_background;

-

-   double i;

-

-   /* First check on the 'perfect' result obtained from the digitized input

-    * value, id, and compare this against the actual digitized result, 'od'.

-    * 'i' is the input result in the range 0..1:

-    */

-   i = isbit; i /= sbit_max;

-

-   /* Check for the fast route: if we don't do any background composition or if

-    * this is the alpha channel ('alpha' < 0) or if the pixel is opaque then

-    * just use the gamma_correction field to correct to the final output gamma.

-    */

-   if (alpha == 1 /* opaque pixel component */ || !do_background

-#ifdef PNG_READ_ALPHA_MODE_SUPPORTED

-      || do_background == ALPHA_MODE_OFFSET + PNG_ALPHA_PNG

-#endif

-      || (alpha < 0 /* alpha channel */

-#ifdef PNG_READ_ALPHA_MODE_SUPPORTED

-      && do_background != ALPHA_MODE_OFFSET + PNG_ALPHA_BROKEN

-#endif

-      ))

-   {

-      /* Then get the gamma corrected version of 'i' and compare to 'od', any

-       * error less than .5 is insignificant - just quantization of the output

-       * value to the nearest digital value (nevertheless the error is still

-       * recorded - it's interesting ;-)

-       */

-      double encoded_sample = i;

-      double encoded_error;

-

-      /* alpha less than 0 indicates the alpha channel, which is always linear

-       */

-      if (alpha >= 0 && vi->gamma_correction > 0)

-         encoded_sample = pow(encoded_sample, vi->gamma_correction);

-      encoded_sample *= outmax;

-

-      encoded_error = fabs(od-encoded_sample);

-

-      if (encoded_error > vi->dp->maxerrout)

-         vi->dp->maxerrout = encoded_error;

-

-      if (encoded_error < vi->maxout_total && encoded_error < vi->outlog)

-         return i;

-   }

-

-   /* The slow route - attempt to do linear calculations. */

-   /* There may be an error, or background processing is required, so calculate

-    * the actual sample values - unencoded light intensity values.  Note that in

-    * practice these are not completely unencoded because they include a

-    * 'viewing correction' to decrease or (normally) increase the perceptual

-    * contrast of the image.  There's nothing we can do about this - we don't

-    * know what it is - so assume the unencoded value is perceptually linear.

-    */

-   {

-      double input_sample = i; /* In range 0..1 */

-      double output, error, encoded_sample, encoded_error;

-      double es_lo, es_hi;

-      int compose = 0;           /* Set to one if composition done */

-      int output_is_encoded;     /* Set if encoded to screen gamma */

-      int log_max_error = 1;     /* Check maximum error values */

-      png_const_charp pass = 0;  /* Reason test passes (or 0 for fail) */

-

-      /* Convert to linear light (with the above caveat.)  The alpha channel is

-       * already linear.

-       */

-      if (alpha >= 0)

-      {

-         int tcompose;

-

-         if (vi->file_inverse > 0)

-            input_sample = pow(input_sample, vi->file_inverse);

-

-         /* Handle the compose processing: */

-         tcompose = 0;

-         input_sample = gamma_component_compose(do_background, input_sample,

-            alpha, background, &tcompose);

-

-         if (tcompose)

-            compose = 1;

-      }

-

-      /* And similarly for the output value, but we need to check the background

-       * handling to linearize it correctly.

-       */

-      output = od;

-      output /= outmax;

-

-      output_is_encoded = vi->screen_gamma > 0;

-

-      if (alpha < 0) /* The alpha channel */

-      {

-#ifdef PNG_READ_ALPHA_MODE_SUPPORTED

-         if (do_background != ALPHA_MODE_OFFSET + PNG_ALPHA_BROKEN)

-#endif

-         {

-            /* In all other cases the output alpha channel is linear already,

-             * don't log errors here, they are much larger in linear data.

-             */

-            output_is_encoded = 0;

-            log_max_error = 0;

-         }

-      }

-

-#ifdef PNG_READ_ALPHA_MODE_SUPPORTED

-      else /* A component */

-      {

-         if (do_background == ALPHA_MODE_OFFSET + PNG_ALPHA_OPTIMIZED &&

-            alpha < 1) /* the optimized case - linear output */

-         {

-            if (alpha > 0) log_max_error = 0;

-            output_is_encoded = 0;

-         }

-      }

-#endif

-

-      if (output_is_encoded)

-         output = pow(output, vi->screen_gamma);

-

-      /* Calculate (or recalculate) the encoded_sample value and repeat the

-       * check above (unnecessary if we took the fast route, but harmless.)

-       */

-      encoded_sample = input_sample;

-      if (output_is_encoded)

-         encoded_sample = pow(encoded_sample, vi->screen_inverse);

-      encoded_sample *= outmax;

-

-      encoded_error = fabs(od-encoded_sample);

-

-      /* Don't log errors in the alpha channel, or the 'optimized' case,

-       * neither are significant to the overall perception.

-       */

-      if (log_max_error && encoded_error > vi->dp->maxerrout)

-         vi->dp->maxerrout = encoded_error;

-

-      if (encoded_error < vi->maxout_total)

-      {

-         if (encoded_error < vi->outlog)

-            return i;

-

-         /* Test passed but error is bigger than the log limit, record why the

-          * test passed:

-          */

-         pass = "less than maxout:\n";

-      }

-

-      /* i: the original input value in the range 0..1

-       *

-       * pngvalid calculations:

-       *  input_sample: linear result; i linearized and composed, range 0..1

-       *  encoded_sample: encoded result; input_sample scaled to ouput bit depth

-       *

-       * libpng calculations:

-       *  output: linear result; od scaled to 0..1 and linearized

-       *  od: encoded result from libpng

-       */

-

-      /* Now we have the numbers for real errors, both absolute values as as a

-       * percentage of the correct value (output):

-       */

-      error = fabs(input_sample-output);

-

-      if (log_max_error && error > vi->dp->maxerrabs)

-         vi->dp->maxerrabs = error;

-

-      /* The following is an attempt to ignore the tendency of quantization to

-       * dominate the percentage errors for lower result values:

-       */

-      if (log_max_error && input_sample > .5)

-      {

-         double percentage_error = error/input_sample;

-         if (percentage_error > vi->dp->maxerrpc)

-            vi->dp->maxerrpc = percentage_error;

-      }

-

-      /* Now calculate the digitization limits for 'encoded_sample' using the

-       * 'max' values.  Note that maxout is in the encoded space but maxpc and

-       * maxabs are in linear light space.

-       *

-       * First find the maximum error in linear light space, range 0..1:

-       */

-      {

-         double tmp = input_sample * vi->maxpc;

-         if (tmp < vi->maxabs) tmp = vi->maxabs;

-         /* If 'compose' is true the composition was done in linear space using

-          * integer arithmetic.  This introduces an extra error of +/- 0.5 (at

-          * least) in the integer space used.  'maxcalc' records this, taking

-          * into account the possibility that even for 16 bit output 8 bit space

-          * may have been used.

-          */

-         if (compose && tmp < vi->maxcalc) tmp = vi->maxcalc;

-

-         /* The 'maxout' value refers to the encoded result, to compare with

-          * this encode input_sample adjusted by the maximum error (tmp) above.

-          */

-         es_lo = encoded_sample - vi->maxout;

-

-         if (es_lo > 0 && input_sample-tmp > 0)

-         {

-            double low_value = input_sample-tmp;

-            if (output_is_encoded)

-               low_value = pow(low_value, vi->screen_inverse);

-            low_value *= outmax;

-            if (low_value < es_lo) es_lo = low_value;

-

-            /* Quantize this appropriately: */

-            es_lo = ceil(es_lo / vi->outquant - .5) * vi->outquant;

-         }

-

-         else

-            es_lo = 0;

-

-         es_hi = encoded_sample + vi->maxout;

-

-         if (es_hi < outmax && input_sample+tmp < 1)

-         {

-            double high_value = input_sample+tmp;

-            if (output_is_encoded)

-               high_value = pow(high_value, vi->screen_inverse);

-            high_value *= outmax;

-            if (high_value > es_hi) es_hi = high_value;

-

-            es_hi = floor(es_hi / vi->outquant + .5) * vi->outquant;

-         }

-

-         else

-            es_hi = outmax;

-      }

-

-      /* The primary test is that the final encoded value returned by the

-       * library should be between the two limits (inclusive) that were

-       * calculated above.

-       */

-      if (od >= es_lo && od <= es_hi)

-      {

-         /* The value passes, but we may need to log the information anyway. */

-         if (encoded_error < vi->outlog)

-            return i;

-

-         if (pass == 0)

-            pass = "within digitization limits:\n";

-      }

-

-      {

-         /* There has been an error in processing, or we need to log this

-          * value.

-          */

-         double is_lo, is_hi;

-

-         /* pass is set at this point if either of the tests above would have

-          * passed.  Don't do these additional tests here - just log the

-          * original [es_lo..es_hi] values.

-          */

-         if (pass == 0 && vi->use_input_precision)

-         {

-            /* Ok, something is wrong - this actually happens in current libpng

-             * 16-to-8 processing.  Assume that the input value (id, adjusted

-             * for sbit) can be anywhere between value-.5 and value+.5 - quite a

-             * large range if sbit is low.

-             */

-            double tmp = (isbit - .5)/sbit_max;

-

-            if (tmp <= 0)

-               tmp = 0;

-

-            else if (alpha >= 0 && vi->file_inverse > 0 && tmp < 1)

-               tmp = pow(tmp, vi->file_inverse);

-

-            tmp = gamma_component_compose(do_background, tmp, alpha, background,

-               NULL);

-

-            if (output_is_encoded && tmp > 0 && tmp < 1)

-               tmp = pow(tmp, vi->screen_inverse);

-

-            is_lo = ceil(outmax * tmp - vi->maxout_total);

-

-            if (is_lo < 0)

-               is_lo = 0;

-

-            tmp = (isbit + .5)/sbit_max;

-

-            if (tmp <= 0)

-               tmp = 0;

-

-            else if (alpha >= 0 && vi->file_inverse > 0 && tmp < 1)

-               tmp = pow(tmp, vi->file_inverse);

-

-            tmp = gamma_component_compose(do_background, tmp, alpha, background,

-               NULL);

-

-            if (output_is_encoded && tmp > 0 && tmp < 1)

-               tmp = pow(tmp, vi->screen_inverse);

-

-            is_hi = floor(outmax * tmp + vi->maxout_total);

-

-            if (is_hi > outmax)

-               is_hi = outmax;

-

-            if (!(od < is_lo || od > is_hi))

-            {

-               if (encoded_error < vi->outlog)

-                  return i;

-

-               pass = "within input precision limits:\n";

-            }

-

-            /* One last chance.  If this is an alpha channel and the 16to8

-             * option has been used and 'inaccurate' scaling is used then the

-             * bit reduction is obtained by simply using the top 8 bits of the

-             * value.

-             *

-             * This is only done for older libpng versions when the 'inaccurate'

-             * (chop) method of scaling was used.

-             */

-#           ifndef PNG_READ_16_TO_8_ACCURATE_SCALE_SUPPORTED

-#              if PNG_LIBPNG_VER < 10504

-                  /* This may be required for other components in the future,

-                   * but at present the presence of gamma correction effectively

-                   * prevents the errors in the component scaling (I don't quite

-                   * understand why, but since it's better this way I care not

-                   * to ask, JB 20110419.)

-                   */

-                  if (pass == 0 && alpha < 0 && vi->scale16 && vi->sbit > 8 &&

-                     vi->sbit + vi->isbit_shift == 16)

-                  {

-                     tmp = ((id >> 8) - .5)/255;

-

-                     if (tmp > 0)

-                     {

-                        is_lo = ceil(outmax * tmp - vi->maxout_total);

-                        if (is_lo < 0) is_lo = 0;

-                     }

-

-                     else

-                        is_lo = 0;

-

-                     tmp = ((id >> 8) + .5)/255;

-

-                     if (tmp < 1)

-                     {

-                        is_hi = floor(outmax * tmp + vi->maxout_total);

-                        if (is_hi > outmax) is_hi = outmax;

-                     }

-

-                     else

-                        is_hi = outmax;

-

-                     if (!(od < is_lo || od > is_hi))

-                     {

-                        if (encoded_error < vi->outlog)

-                           return i;

-

-                        pass = "within 8 bit limits:\n";

-                     }

-                  }

-#              endif

-#           endif

-         }

-         else /* !use_input_precision */

-            is_lo = es_lo, is_hi = es_hi;

-

-         /* Attempt to output a meaningful error/warning message: the message

-          * output depends on the background/composite operation being performed

-          * because this changes what parameters were actually used above.

-          */

-         {

-            size_t pos = 0;

-            /* Need either 1/255 or 1/65535 precision here; 3 or 6 decimal

-             * places.  Just use outmax to work out which.

-             */

-            int precision = (outmax >= 1000 ? 6 : 3);

-            int use_input=1, use_background=0, do_compose=0;

-            char msg[256];

-

-            if (pass != 0)

-               pos = safecat(msg, sizeof msg, pos, "\n\t");

-

-            /* Set up the various flags, the output_is_encoded flag above

-             * is also used below.  do_compose is just a double check.

-             */

-            switch (do_background)

-            {

-            case PNG_BACKGROUND_GAMMA_SCREEN:

-            case PNG_BACKGROUND_GAMMA_FILE:

-            case PNG_BACKGROUND_GAMMA_UNIQUE:

-               use_background = (alpha >= 0 && alpha < 1);

-               /*FALL THROUGH*/

-#           ifdef PNG_READ_ALPHA_MODE_SUPPORTED

-               case ALPHA_MODE_OFFSET + PNG_ALPHA_STANDARD:

-               case ALPHA_MODE_OFFSET + PNG_ALPHA_BROKEN:

-               case ALPHA_MODE_OFFSET + PNG_ALPHA_OPTIMIZED:

-#           endif /* ALPHA_MODE_SUPPORTED */

-               do_compose = (alpha > 0 && alpha < 1);

-               use_input = (alpha != 0);

-               break;

-

-            default:

-               break;

-            }

-

-            /* Check the 'compose' flag */

-            if (compose != do_compose)

-               png_error(vi->pp, "internal error (compose)");

-

-            /* 'name' is the component name */

-            pos = safecat(msg, sizeof msg, pos, name);

-            pos = safecat(msg, sizeof msg, pos, "(");

-            pos = safecatn(msg, sizeof msg, pos, id);

-            if (use_input || pass != 0/*logging*/)

-            {

-               if (isbit != id)

-               {

-                  /* sBIT has reduced the precision of the input: */

-                  pos = safecat(msg, sizeof msg, pos, ", sbit(");

-                  pos = safecatn(msg, sizeof msg, pos, vi->sbit);

-                  pos = safecat(msg, sizeof msg, pos, "): ");

-                  pos = safecatn(msg, sizeof msg, pos, isbit);

-               }

-               pos = safecat(msg, sizeof msg, pos, "/");

-               /* The output is either "id/max" or "id sbit(sbit): isbit/max" */

-               pos = safecatn(msg, sizeof msg, pos, vi->sbit_max);

-            }

-            pos = safecat(msg, sizeof msg, pos, ")");

-

-            /* A component may have been multiplied (in linear space) by the

-             * alpha value, 'compose' says whether this is relevant.

-             */

-            if (compose || pass != 0)

-            {

-               /* If any form of composition is being done report our

-                * calculated linear value here (the code above doesn't record

-                * the input value before composition is performed, so what

-                * gets reported is the value after composition.)

-                */

-               if (use_input || pass != 0)

-               {

-                  if (vi->file_inverse > 0)

-                  {

-                     pos = safecat(msg, sizeof msg, pos, "^");

-                     pos = safecatd(msg, sizeof msg, pos, vi->file_inverse, 2);

-                  }

-

-                  else

-                     pos = safecat(msg, sizeof msg, pos, "[linear]");

-

-                  pos = safecat(msg, sizeof msg, pos, "*(alpha)");

-                  pos = safecatd(msg, sizeof msg, pos, alpha, precision);

-               }

-

-               /* Now record the *linear* background value if it was used

-                * (this function is not passed the original, non-linear,

-                * value but it is contained in the test name.)

-                */

-               if (use_background)

-               {

-                  pos = safecat(msg, sizeof msg, pos, use_input ? "+" : " ");

-                  pos = safecat(msg, sizeof msg, pos, "(background)");

-                  pos = safecatd(msg, sizeof msg, pos, background, precision);

-                  pos = safecat(msg, sizeof msg, pos, "*");

-                  pos = safecatd(msg, sizeof msg, pos, 1-alpha, precision);

-               }

-            }

-

-            /* Report the calculated value (input_sample) and the linearized

-             * libpng value (output) unless this is just a component gamma

-             * correction.

-             */

-            if (compose || alpha < 0 || pass != 0)

-            {

-               pos = safecat(msg, sizeof msg, pos,

-                  pass != 0 ? " =\n\t" : " = ");

-               pos = safecatd(msg, sizeof msg, pos, input_sample, precision);

-               pos = safecat(msg, sizeof msg, pos, " (libpng: ");

-               pos = safecatd(msg, sizeof msg, pos, output, precision);

-               pos = safecat(msg, sizeof msg, pos, ")");

-

-               /* Finally report the output gamma encoding, if any. */

-               if (output_is_encoded)

-               {

-                  pos = safecat(msg, sizeof msg, pos, " ^");

-                  pos = safecatd(msg, sizeof msg, pos, vi->screen_inverse, 2);

-                  pos = safecat(msg, sizeof msg, pos, "(to screen) =");

-               }

-

-               else

-                  pos = safecat(msg, sizeof msg, pos, " [screen is linear] =");

-            }

-

-            if ((!compose && alpha >= 0) || pass != 0)

-            {

-               if (pass != 0) /* logging */

-                  pos = safecat(msg, sizeof msg, pos, "\n\t[overall:");

-

-               /* This is the non-composition case, the internal linear

-                * values are irrelevant (though the log below will reveal

-                * them.)  Output a much shorter warning/error message and report

-                * the overall gamma correction.

-                */

-               if (vi->gamma_correction > 0)

-               {

-                  pos = safecat(msg, sizeof msg, pos, " ^");

-                  pos = safecatd(msg, sizeof msg, pos, vi->gamma_correction, 2);

-                  pos = safecat(msg, sizeof msg, pos, "(gamma correction) =");

-               }

-

-               else

-                  pos = safecat(msg, sizeof msg, pos,

-                     " [no gamma correction] =");

-

-               if (pass != 0)

-                  pos = safecat(msg, sizeof msg, pos, "]");

-            }

-

-            /* This is our calculated encoded_sample which should (but does

-             * not) match od:

-             */

-            pos = safecat(msg, sizeof msg, pos, pass != 0 ? "\n\t" : " ");

-            pos = safecatd(msg, sizeof msg, pos, is_lo, 1);

-            pos = safecat(msg, sizeof msg, pos, " < ");

-            pos = safecatd(msg, sizeof msg, pos, encoded_sample, 1);

-            pos = safecat(msg, sizeof msg, pos, " (libpng: ");

-            pos = safecatn(msg, sizeof msg, pos, od);

-            pos = safecat(msg, sizeof msg, pos, ")");

-            pos = safecat(msg, sizeof msg, pos, "/");

-            pos = safecatn(msg, sizeof msg, pos, outmax);

-            pos = safecat(msg, sizeof msg, pos, " < ");

-            pos = safecatd(msg, sizeof msg, pos, is_hi, 1);

-

-            if (pass == 0) /* The error condition */

-            {

-#              ifdef PNG_WARNINGS_SUPPORTED

-                  png_warning(vi->pp, msg);

-#              else

-                  store_warning(vi->pp, msg);

-#              endif

-            }

-

-            else /* logging this value */

-               store_verbose(&vi->dp->pm->this, vi->pp, pass, msg);

-         }

-      }

-   }

-

-   return i;

-}

-

-static void

-gamma_image_validate(gamma_display *dp, png_structp pp, png_infop pi)

-{

-   /* Get some constants derived from the input and output file formats: */

-   PNG_CONST png_store* PNG_CONST ps = dp->this.ps;

-   PNG_CONST png_byte in_ct = dp->this.colour_type;

-   PNG_CONST png_byte in_bd = dp->this.bit_depth;

-   PNG_CONST png_uint_32 w = dp->this.w;

-   PNG_CONST png_uint_32 h = dp->this.h;

-   PNG_CONST size_t cbRow = dp->this.cbRow;

-   PNG_CONST png_byte out_ct = png_get_color_type(pp, pi);

-   PNG_CONST png_byte out_bd = png_get_bit_depth(pp, pi);

-

-   /* There are three sources of error, firstly the quantization in the

-    * file encoding, determined by sbit and/or the file depth, secondly

-    * the output (screen) gamma and thirdly the output file encoding.

-    *

-    * Since this API receives the screen and file gamma in double

-    * precision it is possible to calculate an exact answer given an input

-    * pixel value.  Therefore we assume that the *input* value is exact -

-    * sample/maxsample - calculate the corresponding gamma corrected

-    * output to the limits of double precision arithmetic and compare with

-    * what libpng returns.

-    *

-    * Since the library must quantize the output to 8 or 16 bits there is

-    * a fundamental limit on the accuracy of the output of +/-.5 - this

-    * quantization limit is included in addition to the other limits

-    * specified by the paramaters to the API.  (Effectively, add .5

-    * everywhere.)

-    *

-    * The behavior of the 'sbit' paramter is defined by section 12.5

-    * (sample depth scaling) of the PNG spec.  That section forces the

-    * decoder to assume that the PNG values have been scaled if sBIT is

-    * present:

-    *

-    *     png-sample = floor( input-sample * (max-out/max-in) + .5);

-    *

-    * This means that only a subset of the possible PNG values should

-    * appear in the input. However, the spec allows the encoder to use a

-    * variety of approximations to the above and doesn't require any

-    * restriction of the values produced.

-    *

-    * Nevertheless the spec requires that the upper 'sBIT' bits of the

-    * value stored in a PNG file be the original sample bits.

-    * Consequently the code below simply scales the top sbit bits by

-    * (1<<sbit)-1 to obtain an original sample value.

-    *

-    * Because there is limited precision in the input it is arguable that

-    * an acceptable result is any valid result from input-.5 to input+.5.

-    * The basic tests below do not do this, however if 'use_input_precision'

-    * is set a subsequent test is performed below.

-    */

-   PNG_CONST unsigned int samples_per_pixel = (out_ct & 2U) ? 3U : 1U;

-   int processing;

-   png_uint_32 y;

-   PNG_CONST store_palette_entry *in_palette = dp->this.palette;

-   PNG_CONST int in_is_transparent = dp->this.is_transparent;

-   int out_npalette = -1;

-   int out_is_transparent = 0; /* Just refers to the palette case */

-   store_palette out_palette;

-   validate_info vi;

-

-   /* Check for row overwrite errors */

-   store_image_check(dp->this.ps, pp, 0);

-

-   /* Supply the input and output sample depths here - 8 for an indexed image,

-    * otherwise the bit depth.

-    */

-   init_validate_info(&vi, dp, pp, in_ct==3?8:in_bd, out_ct==3?8:out_bd);

-

-   processing = (vi.gamma_correction > 0 && !dp->threshold_test)

-      || in_bd != out_bd || in_ct != out_ct || vi.do_background;

-

-   /* TODO: FIX THIS: MAJOR BUG!  If the transformations all happen inside

-    * the palette there is no way of finding out, because libpng fails to

-    * update the palette on png_read_update_info.  Indeed, libpng doesn't

-    * even do the required work until much later, when it doesn't have any

-    * info pointer.  Oops.  For the moment 'processing' is turned off if

-    * out_ct is palette.

-    */

-   if (in_ct == 3 && out_ct == 3)

-      processing = 0;

-

-   if (processing && out_ct == 3)

-      out_is_transparent = read_palette(out_palette, &out_npalette, pp, pi);

-

-   for (y=0; y<h; ++y)

-   {

-      png_const_bytep pRow = store_image_row(ps, pp, 0, y);

-      png_byte std[STANDARD_ROWMAX];

-

-      transform_row(pp, std, in_ct, in_bd, y);

-

-      if (processing)

-      {

-         unsigned int x;

-

-         for (x=0; x<w; ++x)

-         {

-            double alpha = 1; /* serves as a flag value */

-

-            /* Record the palette index for index images. */

-            PNG_CONST unsigned int in_index =

-               in_ct == 3 ? sample(std, 3, in_bd, x, 0) : 256;

-            PNG_CONST unsigned int out_index =

-               out_ct == 3 ? sample(std, 3, out_bd, x, 0) : 256;

-

-            /* Handle input alpha - png_set_background will cause the output

-             * alpha to disappear so there is nothing to check.

-             */

-            if ((in_ct & PNG_COLOR_MASK_ALPHA) != 0 || (in_ct == 3 &&

-               in_is_transparent))

-            {

-               PNG_CONST unsigned int input_alpha = in_ct == 3 ?

-                  dp->this.palette[in_index].alpha :

-                  sample(std, in_ct, in_bd, x, samples_per_pixel);

-

-               unsigned int output_alpha = 65536 /* as a flag value */;

-

-               if (out_ct == 3)

-               {

-                  if (out_is_transparent)

-                     output_alpha = out_palette[out_index].alpha;

-               }

-

-               else if ((out_ct & PNG_COLOR_MASK_ALPHA) != 0)

-                  output_alpha = sample(pRow, out_ct, out_bd, x,

-                     samples_per_pixel);

-

-               if (output_alpha != 65536)

-                  alpha = gamma_component_validate("alpha", &vi, input_alpha,

-                     output_alpha, -1/*alpha*/, 0/*background*/);

-

-               else /* no alpha in output */

-               {

-                  /* This is a copy of the calculation of 'i' above in order to

-                   * have the alpha value to use in the background calculation.

-                   */

-                  alpha = input_alpha >> vi.isbit_shift;

-                  alpha /= vi.sbit_max;

-               }

-            }

-

-            /* Handle grayscale or RGB components. */

-            if ((in_ct & PNG_COLOR_MASK_COLOR) == 0) /* grayscale */

-               (void)gamma_component_validate("gray", &vi,

-                  sample(std, in_ct, in_bd, x, 0),

-                  sample(pRow, out_ct, out_bd, x, 0), alpha/*component*/,

-                  vi.background_red);

-            else /* RGB or palette */

-            {

-               (void)gamma_component_validate("red", &vi,

-                  in_ct == 3 ? in_palette[in_index].red :

-                     sample(std, in_ct, in_bd, x, 0),

-                  out_ct == 3 ? out_palette[out_index].red :

-                     sample(pRow, out_ct, out_bd, x, 0),

-                  alpha/*component*/, vi.background_red);

-

-               (void)gamma_component_validate("green", &vi,

-                  in_ct == 3 ? in_palette[in_index].green :

-                     sample(std, in_ct, in_bd, x, 1),

-                  out_ct == 3 ? out_palette[out_index].green :

-                     sample(pRow, out_ct, out_bd, x, 1),

-                  alpha/*component*/, vi.background_green);

-

-               (void)gamma_component_validate("blue", &vi,

-                  in_ct == 3 ? in_palette[in_index].blue :

-                     sample(std, in_ct, in_bd, x, 2),

-                  out_ct == 3 ? out_palette[out_index].blue :

-                     sample(pRow, out_ct, out_bd, x, 2),

-                  alpha/*component*/, vi.background_blue);

-            }

-         }

-      }

-

-      else if (memcmp(std, pRow, cbRow) != 0)

-      {

-         char msg[64];

-

-         /* No transform is expected on the threshold tests. */

-         sprintf(msg, "gamma: below threshold row %d changed", y);

-

-         png_error(pp, msg);

-      }

-   } /* row (y) loop */

-

-   dp->this.ps->validated = 1;

-}

-

-static void

-gamma_end(png_structp pp, png_infop pi)

-{

-   gamma_display *dp = voidcast(gamma_display*, png_get_progressive_ptr(pp));

-

-   if (!dp->this.speed)

-      gamma_image_validate(dp, pp, pi);

-   else

-      dp->this.ps->validated = 1;

-}

-

-/* A single test run checking a gamma transformation.

- *

- * maxabs: maximum absolute error as a fraction

- * maxout: maximum output error in the output units

- * maxpc:  maximum percentage error (as a percentage)

- */

-static void

-gamma_test(png_modifier *pmIn, PNG_CONST png_byte colour_typeIn,

-    PNG_CONST png_byte bit_depthIn, PNG_CONST int palette_numberIn,

-    PNG_CONST int interlace_typeIn,

-    PNG_CONST double file_gammaIn, PNG_CONST double screen_gammaIn,

-    PNG_CONST png_byte sbitIn, PNG_CONST int threshold_testIn,

-    PNG_CONST char *name,

-    PNG_CONST int use_input_precisionIn, PNG_CONST int scale16In,

-    PNG_CONST int expand16In, PNG_CONST int do_backgroundIn,

-    PNG_CONST png_color_16 *bkgd_colorIn, double bkgd_gammaIn)

-{

-   gamma_display d;

-   context(&pmIn->this, fault);

-

-   gamma_display_init(&d, pmIn, FILEID(colour_typeIn, bit_depthIn,

-      palette_numberIn, interlace_typeIn, 0, 0, 0),

-      file_gammaIn, screen_gammaIn, sbitIn,

-      threshold_testIn, use_input_precisionIn, scale16In,

-      expand16In, do_backgroundIn, bkgd_colorIn, bkgd_gammaIn);

-

-   Try

-   {

-      png_structp pp;

-      png_infop pi;

-      gama_modification gama_mod;

-      srgb_modification srgb_mod;

-      sbit_modification sbit_mod;

-

-      /* For the moment don't use the png_modifier support here. */

-      d.pm->encoding_counter = 0;

-      modifier_set_encoding(d.pm); /* Just resets everything */

-      d.pm->current_gamma = d.file_gamma;

-

-      /* Make an appropriate modifier to set the PNG file gamma to the

-       * given gamma value and the sBIT chunk to the given precision.

-       */

-      d.pm->modifications = NULL;

-      gama_modification_init(&gama_mod, d.pm, d.file_gamma);

-      srgb_modification_init(&srgb_mod, d.pm, 127 /*delete*/);

-      if (d.sbit > 0)

-         sbit_modification_init(&sbit_mod, d.pm, d.sbit);

-

-      modification_reset(d.pm->modifications);

-

-      /* Get a png_struct for writing the image. */

-      pp = set_modifier_for_read(d.pm, &pi, d.this.id, name);

-      standard_palette_init(&d.this);

-

-      /* Introduce the correct read function. */

-      if (d.pm->this.progressive)

-      {

-         /* Share the row function with the standard implementation. */

-         png_set_progressive_read_fn(pp, &d, gamma_info, progressive_row,

-            gamma_end);

-

-         /* Now feed data into the reader until we reach the end: */

-         modifier_progressive_read(d.pm, pp, pi);

-      }

-      else

-      {

-         /* modifier_read expects a png_modifier* */

-         png_set_read_fn(pp, d.pm, modifier_read);

-

-         /* Check the header values: */

-         png_read_info(pp, pi);

-

-         /* Process the 'info' requirements. Only one image is generated */

-         gamma_info_imp(&d, pp, pi);

-

-         sequential_row(&d.this, pp, pi, -1, 0);

-

-         if (!d.this.speed)

-            gamma_image_validate(&d, pp, pi);

-         else

-            d.this.ps->validated = 1;

-      }

-

-      modifier_reset(d.pm);

-

-      if (d.pm->log && !d.threshold_test && !d.this.speed)

-         fprintf(stderr, "%d bit %s %s: max error %f (%.2g, %2g%%)\n",

-            d.this.bit_depth, colour_types[d.this.colour_type], name,

-            d.maxerrout, d.maxerrabs, 100*d.maxerrpc);

-

-      /* Log the summary values too. */

-      if (d.this.colour_type == 0 || d.this.colour_type == 4)

-      {

-         switch (d.this.bit_depth)

-         {

-         case 1:

-            break;

-

-         case 2:

-            if (d.maxerrout > d.pm->error_gray_2)

-               d.pm->error_gray_2 = d.maxerrout;

-

-            break;

-

-         case 4:

-            if (d.maxerrout > d.pm->error_gray_4)

-               d.pm->error_gray_4 = d.maxerrout;

-

-            break;

-

-         case 8:

-            if (d.maxerrout > d.pm->error_gray_8)

-               d.pm->error_gray_8 = d.maxerrout;

-

-            break;

-

-         case 16:

-            if (d.maxerrout > d.pm->error_gray_16)

-               d.pm->error_gray_16 = d.maxerrout;

-

-            break;

-

-         default:

-            png_error(pp, "bad bit depth (internal: 1)");

-         }

-      }

-

-      else if (d.this.colour_type == 2 || d.this.colour_type == 6)

-      {

-         switch (d.this.bit_depth)

-         {

-         case 8:

-

-            if (d.maxerrout > d.pm->error_color_8)

-               d.pm->error_color_8 = d.maxerrout;

-

-            break;

-

-         case 16:

-

-            if (d.maxerrout > d.pm->error_color_16)

-               d.pm->error_color_16 = d.maxerrout;

-

-            break;

-

-         default:

-            png_error(pp, "bad bit depth (internal: 2)");

-         }

-      }

-

-      else if (d.this.colour_type == 3)

-      {

-         if (d.maxerrout > d.pm->error_indexed)

-            d.pm->error_indexed = d.maxerrout;

-      }

-   }

-

-   Catch(fault)

-      modifier_reset((png_modifier*)fault);

-}

-

-static void gamma_threshold_test(png_modifier *pm, png_byte colour_type,

-    png_byte bit_depth, int interlace_type, double file_gamma,

-    double screen_gamma)

-{

-   size_t pos = 0;

-   char name[64];

-   pos = safecat(name, sizeof name, pos, "threshold ");

-   pos = safecatd(name, sizeof name, pos, file_gamma, 3);

-   pos = safecat(name, sizeof name, pos, "/");

-   pos = safecatd(name, sizeof name, pos, screen_gamma, 3);

-

-   (void)gamma_test(pm, colour_type, bit_depth, 0/*palette*/, interlace_type,

-      file_gamma, screen_gamma, 0/*sBIT*/, 1/*threshold test*/, name,

-      0 /*no input precision*/,

-      0 /*no scale16*/, 0 /*no expand16*/, 0 /*no background*/, 0 /*hence*/,

-      0 /*no background gamma*/);

-}

-

-static void

-perform_gamma_threshold_tests(png_modifier *pm)

-{

-   png_byte colour_type = 0;

-   png_byte bit_depth = 0;

-   int palette_number = 0;

-

-   /* Don't test more than one instance of each palette - it's pointless, in

-    * fact this test is somewhat excessive since libpng doesn't make this

-    * decision based on colour type or bit depth!

-    */

-   while (next_format(&colour_type, &bit_depth, &palette_number))

-      if (palette_number == 0)

-   {

-      double test_gamma = 1.0;

-      while (test_gamma >= .4)

-      {

-         /* There's little point testing the interlacing vs non-interlacing,

-          * but this can be set from the command line.

-          */

-         gamma_threshold_test(pm, colour_type, bit_depth, pm->interlace_type,

-            test_gamma, 1/test_gamma);

-         test_gamma *= .95;

-      }

-

-      /* And a special test for sRGB */

-      gamma_threshold_test(pm, colour_type, bit_depth, pm->interlace_type,

-          .45455, 2.2);

-

-      if (fail(pm))

-         return;

-   }

-}

-

-static void gamma_transform_test(png_modifier *pm,

-   PNG_CONST png_byte colour_type, PNG_CONST png_byte bit_depth,

-   PNG_CONST int palette_number,

-   PNG_CONST int interlace_type, PNG_CONST double file_gamma,

-   PNG_CONST double screen_gamma, PNG_CONST png_byte sbit,

-   PNG_CONST int use_input_precision, PNG_CONST int scale16)

-{

-   size_t pos = 0;

-   char name[64];

-

-   if (sbit != bit_depth && sbit != 0)

-   {

-      pos = safecat(name, sizeof name, pos, "sbit(");

-      pos = safecatn(name, sizeof name, pos, sbit);

-      pos = safecat(name, sizeof name, pos, ") ");

-   }

-

-   else

-      pos = safecat(name, sizeof name, pos, "gamma ");

-

-   if (scale16)

-      pos = safecat(name, sizeof name, pos, "16to8 ");

-

-   pos = safecatd(name, sizeof name, pos, file_gamma, 3);

-   pos = safecat(name, sizeof name, pos, "->");

-   pos = safecatd(name, sizeof name, pos, screen_gamma, 3);

-

-   gamma_test(pm, colour_type, bit_depth, palette_number, interlace_type,

-      file_gamma, screen_gamma, sbit, 0, name, use_input_precision,

-      scale16, pm->test_gamma_expand16, 0 , 0, 0);

-}

-

-static void perform_gamma_transform_tests(png_modifier *pm)

-{

-   png_byte colour_type = 0;

-   png_byte bit_depth = 0;

-   int palette_number = 0;

-

-   while (next_format(&colour_type, &bit_depth, &palette_number))

-   {

-      unsigned int i, j;

-

-      for (i=0; i<pm->ngamma_tests; ++i) for (j=0; j<pm->ngamma_tests; ++j)

-         if (i != j)

-         {

-            gamma_transform_test(pm, colour_type, bit_depth, palette_number,

-               pm->interlace_type, 1/pm->gammas[i], pm->gammas[j], 0/*sBIT*/,

-               pm->use_input_precision, 0 /*do not scale16*/);

-

-            if (fail(pm))

-               return;

-         }

-   }

-}

-

-static void perform_gamma_sbit_tests(png_modifier *pm)

-{

-   png_byte sbit;

-

-   /* The only interesting cases are colour and grayscale, alpha is ignored here

-    * for overall speed.  Only bit depths where sbit is less than the bit depth

-    * are tested.

-    */

-   for (sbit=pm->sbitlow; sbit<(1<<READ_BDHI); ++sbit)

-   {

-      png_byte colour_type, bit_depth;

-      int npalette;

-

-      colour_type = bit_depth = 0;

-      npalette = 0;

-

-      while (next_format(&colour_type, &bit_depth, &npalette))

-         if ((colour_type & PNG_COLOR_MASK_ALPHA) == 0 &&

-            ((colour_type == 3 && sbit < 8) ||

-            (colour_type != 3 && sbit < bit_depth)))

-      {

-         unsigned int i;

-

-         for (i=0; i<pm->ngamma_tests; ++i)

-         {

-            unsigned int j;

-

-            for (j=0; j<pm->ngamma_tests; ++j) if (i != j)

-            {

-               gamma_transform_test(pm, colour_type, bit_depth, npalette,

-                  pm->interlace_type, 1/pm->gammas[i], pm->gammas[j],

-                  sbit, pm->use_input_precision_sbit, 0 /*scale16*/);

-

-               if (fail(pm))

-                  return;

-            }

-         }

-      }

-   }

-}

-

-/* Note that this requires a 16 bit source image but produces 8 bit output, so

- * we only need the 16bit write support, but the 16 bit images are only

- * generated if DO_16BIT is defined.

- */

-#ifdef DO_16BIT

-static void perform_gamma_scale16_tests(png_modifier *pm)

-{

-#  ifndef PNG_MAX_GAMMA_8

-#     define PNG_MAX_GAMMA_8 11

-#  endif

-   /* Include the alpha cases here. Note that sbit matches the internal value

-    * used by the library - otherwise we will get spurious errors from the

-    * internal sbit style approximation.

-    *

-    * The threshold test is here because otherwise the 16 to 8 conversion will

-    * proceed *without* gamma correction, and the tests above will fail (but not

-    * by much) - this could be fixed, it only appears with the -g option.

-    */

-   unsigned int i, j;

-   for (i=0; i<pm->ngamma_tests; ++i)

-   {

-      for (j=0; j<pm->ngamma_tests; ++j)

-      {

-         if (i != j &&

-             fabs(pm->gammas[j]/pm->gammas[i]-1) >= PNG_GAMMA_THRESHOLD)

-         {

-            gamma_transform_test(pm, 0, 16, 0, pm->interlace_type,

-               1/pm->gammas[i], pm->gammas[j], PNG_MAX_GAMMA_8,

-               pm->use_input_precision_16to8, 1 /*scale16*/);

-

-            if (fail(pm))

-               return;

-

-            gamma_transform_test(pm, 2, 16, 0, pm->interlace_type,

-               1/pm->gammas[i], pm->gammas[j], PNG_MAX_GAMMA_8,

-               pm->use_input_precision_16to8, 1 /*scale16*/);

-

-            if (fail(pm))

-               return;

-

-            gamma_transform_test(pm, 4, 16, 0, pm->interlace_type,

-               1/pm->gammas[i], pm->gammas[j], PNG_MAX_GAMMA_8,

-               pm->use_input_precision_16to8, 1 /*scale16*/);

-

-            if (fail(pm))

-               return;

-

-            gamma_transform_test(pm, 6, 16, 0, pm->interlace_type,

-               1/pm->gammas[i], pm->gammas[j], PNG_MAX_GAMMA_8,

-               pm->use_input_precision_16to8, 1 /*scale16*/);

-

-            if (fail(pm))

-               return;

-         }

-      }

-   }

-}

-#endif /* 16 to 8 bit conversion */

-

-#if defined PNG_READ_BACKGROUND_SUPPORTED ||\

-   defined PNG_READ_ALPHA_MODE_SUPPORTED

-static void gamma_composition_test(png_modifier *pm,

-   PNG_CONST png_byte colour_type, PNG_CONST png_byte bit_depth,

-   PNG_CONST int palette_number,

-   PNG_CONST int interlace_type, PNG_CONST double file_gamma,

-   PNG_CONST double screen_gamma,

-   PNG_CONST int use_input_precision, PNG_CONST int do_background,

-   PNG_CONST int expand_16)

-{

-   size_t pos = 0;

-   png_const_charp base;

-   double bg;

-   char name[128];

-   png_color_16 background;

-

-   /* Make up a name and get an appropriate background gamma value. */

-   switch (do_background)

-   {

-      default:

-         base = "";

-         bg = 4; /* should not be used */

-         break;

-      case PNG_BACKGROUND_GAMMA_SCREEN:

-         base = " bckg(Screen):";

-         bg = 1/screen_gamma;

-         break;

-      case PNG_BACKGROUND_GAMMA_FILE:

-         base = " bckg(File):";

-         bg = file_gamma;

-         break;

-      case PNG_BACKGROUND_GAMMA_UNIQUE:

-         base = " bckg(Unique):";

-         /* This tests the handling of a unique value, the math is such that the

-          * value tends to be <1, but is neither screen nor file (even if they

-          * match!)

-          */

-         bg = (file_gamma + screen_gamma) / 3;

-         break;

-#ifdef PNG_READ_ALPHA_MODE_SUPPORTED

-      case ALPHA_MODE_OFFSET + PNG_ALPHA_PNG:

-         base = " alpha(PNG)";

-         bg = 4; /* should not be used */

-         break;

-      case ALPHA_MODE_OFFSET + PNG_ALPHA_STANDARD:

-         base = " alpha(Porter-Duff)";

-         bg = 4; /* should not be used */

-         break;

-      case ALPHA_MODE_OFFSET + PNG_ALPHA_OPTIMIZED:

-         base = " alpha(Optimized)";

-         bg = 4; /* should not be used */

-         break;

-      case ALPHA_MODE_OFFSET + PNG_ALPHA_BROKEN:

-         base = " alpha(Broken)";

-         bg = 4; /* should not be used */

-         break;

-#endif

-   }

-

-   /* Use random background values - the background is always presented in the

-    * output space (8 or 16 bit components).

-    */

-   if (expand_16 || bit_depth == 16)

-   {

-      png_uint_32 r = random_32();

-

-      background.red = (png_uint_16)r;

-      background.green = (png_uint_16)(r >> 16);

-      r = random_32();

-      background.blue = (png_uint_16)r;

-      background.gray = (png_uint_16)(r >> 16);

-   }

-

-   else /* 8 bit colors */

-   {

-      png_uint_32 r = random_32();

-

-      background.red = (png_byte)r;

-      background.green = (png_byte)(r >> 8);

-      background.blue = (png_byte)(r >> 16);

-      background.gray = (png_byte)(r >> 24);

-   }

-

-   background.index = 193; /* rgb(193,193,193) to detect errors */

-   if (!(colour_type & PNG_COLOR_MASK_COLOR))

-   {

-      /* Grayscale input, we do not convert to RGB (TBD), so we must set the

-       * background to gray - else libpng seems to fail.

-       */

-      background.red = background.green = background.blue = background.gray;

-   }

-

-   pos = safecat(name, sizeof name, pos, "gamma ");

-   pos = safecatd(name, sizeof name, pos, file_gamma, 3);

-   pos = safecat(name, sizeof name, pos, "->");

-   pos = safecatd(name, sizeof name, pos, screen_gamma, 3);

-

-   pos = safecat(name, sizeof name, pos, base);

-   if (do_background < ALPHA_MODE_OFFSET)

-   {

-      /* Include the background color and gamma in the name: */

-      pos = safecat(name, sizeof name, pos, "(");

-      /* This assumes no expand gray->rgb - the current code won't handle that!

-       */

-      if (colour_type & PNG_COLOR_MASK_COLOR)

-      {

-         pos = safecatn(name, sizeof name, pos, background.red);

-         pos = safecat(name, sizeof name, pos, ",");

-         pos = safecatn(name, sizeof name, pos, background.green);

-         pos = safecat(name, sizeof name, pos, ",");

-         pos = safecatn(name, sizeof name, pos, background.blue);

-      }

-      else

-         pos = safecatn(name, sizeof name, pos, background.gray);

-      pos = safecat(name, sizeof name, pos, ")^");

-      pos = safecatd(name, sizeof name, pos, bg, 3);

-   }

-

-   gamma_test(pm, colour_type, bit_depth, palette_number, interlace_type,

-      file_gamma, screen_gamma, 0/*sBIT*/, 0, name, use_input_precision,

-      0/*strip 16*/, expand_16, do_background, &background, bg);

-}

-

-

-static void

-perform_gamma_composition_tests(png_modifier *pm, int do_background,

-   int expand_16)

-{

-   png_byte colour_type = 0;

-   png_byte bit_depth = 0;

-   int palette_number = 0;

-

-   /* Skip the non-alpha cases - there is no setting of a transparency colour at

-    * present.

-    */

-   while (next_format(&colour_type, &bit_depth, &palette_number))

-      if ((colour_type & PNG_COLOR_MASK_ALPHA) != 0)

-   {

-      unsigned int i, j;

-

-      /* Don't skip the i==j case here - it's relevant. */

-      for (i=0; i<pm->ngamma_tests; ++i) for (j=0; j<pm->ngamma_tests; ++j)

-      {

-         gamma_composition_test(pm, colour_type, bit_depth, palette_number,

-            pm->interlace_type, 1/pm->gammas[i], pm->gammas[j],

-            pm->use_input_precision, do_background, expand_16);

-

-         if (fail(pm))

-            return;

-      }

-   }

-}

-#endif /* READ_BACKGROUND || READ_ALPHA_MODE */

-

-static void

-init_gamma_errors(png_modifier *pm)

-{

-   pm->error_gray_2 = pm->error_gray_4 = pm->error_gray_8 = 0;

-   pm->error_color_8 = 0;

-   pm->error_indexed = 0;

-   pm->error_gray_16 = pm->error_color_16 = 0;

-}

-

-static void

-summarize_gamma_errors(png_modifier *pm, png_const_charp who, int low_bit_depth)

-{

-   if (who)

-      printf("Gamma correction with %s:\n", who);

-

-   if (low_bit_depth)

-   {

-      printf("  2 bit gray:  %.5f\n", pm->error_gray_2);

-      printf("  4 bit gray:  %.5f\n", pm->error_gray_4);

-      printf("  8 bit gray:  %.5f\n", pm->error_gray_8);

-      printf("  8 bit color: %.5f\n", pm->error_color_8);

-      printf("  indexed:     %.5f\n", pm->error_indexed);

-   }

-

-#ifdef DO_16BIT

-   printf(" 16 bit gray:  %.5f\n", pm->error_gray_16);

-   printf(" 16 bit color: %.5f\n", pm->error_color_16);

-#endif

-}

-

-static void

-perform_gamma_test(png_modifier *pm, int summary)

-{

-   /*TODO: remove this*/

-   /* Save certain values for the temporary overrides below. */

-   unsigned int calculations_use_input_precision =

-      pm->calculations_use_input_precision;

-   double maxout8 = pm->maxout8;

-

-   /* First some arbitrary no-transform tests: */

-   if (!pm->this.speed && pm->test_gamma_threshold)

-   {

-      perform_gamma_threshold_tests(pm);

-

-      if (fail(pm))

-         return;

-   }

-

-   /* Now some real transforms. */

-   if (pm->test_gamma_transform)

-   {

-      init_gamma_errors(pm);

-      /*TODO: remove this.  Necessary because the current libpng

-       * implementation works in 8 bits:

-       */

-      if (pm->test_gamma_expand16)

-         pm->calculations_use_input_precision = 1;

-      perform_gamma_transform_tests(pm);

-      if (!calculations_use_input_precision)

-         pm->calculations_use_input_precision = 0;

-

-      if (summary)

-      {

-         printf("Gamma correction error summary\n\n");

-         printf("The printed value is the maximum error in the pixel values\n");

-         printf("calculated by the libpng gamma correction code.  The error\n");

-         printf("is calculated as the difference between the output pixel\n");

-         printf("value (always an integer) and the ideal value from the\n");

-         printf("libpng specification (typically not an integer).\n\n");

-

-         printf("Expect this value to be less than .5 for 8 bit formats,\n");

-         printf("less than 1 for formats with fewer than 8 bits and a small\n");

-         printf("number (typically less than 5) for the 16 bit formats.\n");

-         printf("For performance reasons the value for 16 bit formats\n");

-         printf("increases when the image file includes an sBIT chunk.\n\n");

-

-         summarize_gamma_errors(pm, 0/*who*/, 1);

-      }

-   }

-

-   /* The sbit tests produce much larger errors: */

-   if (pm->test_gamma_sbit)

-   {

-      init_gamma_errors(pm);

-      perform_gamma_sbit_tests(pm);

-

-      if (summary)

-         summarize_gamma_errors(pm, "sBIT", pm->sbitlow < 8U);

-   }

-

-#ifdef DO_16BIT /* Should be READ_16BIT_SUPPORTED */

-   if (pm->test_gamma_scale16)

-   {

-      /* The 16 to 8 bit strip operations: */

-      init_gamma_errors(pm);

-      perform_gamma_scale16_tests(pm);

-

-      if (summary)

-      {

-         printf("Gamma correction with 16 to 8 bit reduction:\n");

-         printf(" 16 bit gray:  %.5f\n", pm->error_gray_16);

-         printf(" 16 bit color: %.5f\n", pm->error_color_16);

-      }

-   }

-#endif

-

-#ifdef PNG_READ_BACKGROUND_SUPPORTED

-   if (pm->test_gamma_background)

-   {

-      init_gamma_errors(pm);

-

-      /*TODO: remove this.  Necessary because the current libpng

-       * implementation works in 8 bits:

-       */

-      if (pm->test_gamma_expand16)

-      {

-         pm->calculations_use_input_precision = 1;

-         pm->maxout8 = .499; /* because the 16 bit background is smashed */

-      }

-      perform_gamma_composition_tests(pm, PNG_BACKGROUND_GAMMA_UNIQUE,

-         pm->test_gamma_expand16);

-      if (!calculations_use_input_precision)

-         pm->calculations_use_input_precision = 0;

-      pm->maxout8 = maxout8;

-

-      if (summary)

-         summarize_gamma_errors(pm, "background", 1);

-   }

-#endif

-

-#ifdef PNG_READ_ALPHA_MODE_SUPPORTED

-   if (pm->test_gamma_alpha_mode)

-   {

-      int do_background;

-

-      init_gamma_errors(pm);

-

-      /*TODO: remove this.  Necessary because the current libpng

-       * implementation works in 8 bits:

-       */

-      if (pm->test_gamma_expand16)

-         pm->calculations_use_input_precision = 1;

-      for (do_background = ALPHA_MODE_OFFSET + PNG_ALPHA_STANDARD;

-         do_background <= ALPHA_MODE_OFFSET + PNG_ALPHA_BROKEN && !fail(pm);

-         ++do_background)

-         perform_gamma_composition_tests(pm, do_background,

-            pm->test_gamma_expand16);

-      if (!calculations_use_input_precision)

-         pm->calculations_use_input_precision = 0;

-

-      if (summary)

-         summarize_gamma_errors(pm, "alpha mode", 1);

-   }

-#endif

-}

-#endif /* PNG_READ_GAMMA_SUPPORTED */

-

-/* INTERLACE MACRO VALIDATION */

-/* This is copied verbatim from the specification, it is simply the pass

- * number in which each pixel in each 8x8 tile appears.  The array must

- * be indexed adam7[y][x] and notice that the pass numbers are based at

- * 1, not 0 - the base libpng uses.

- */

-static PNG_CONST

-png_byte adam7[8][8] =

-{

-   { 1,6,4,6,2,6,4,6 },

-   { 7,7,7,7,7,7,7,7 },

-   { 5,6,5,6,5,6,5,6 },

-   { 7,7,7,7,7,7,7,7 },

-   { 3,6,4,6,3,6,4,6 },

-   { 7,7,7,7,7,7,7,7 },

-   { 5,6,5,6,5,6,5,6 },

-   { 7,7,7,7,7,7,7,7 }

-};

-

-/* This routine validates all the interlace support macros in png.h for

- * a variety of valid PNG widths and heights.  It uses a number of similarly

- * named internal routines that feed off the above array.

- */

-static png_uint_32

-png_pass_start_row(int pass)

-{

-   int x, y;

-   ++pass;

-   for (y=0; y<8; ++y) for (x=0; x<8; ++x) if (adam7[y][x] == pass)

-      return y;

-   return 0xf;

-}

-

-static png_uint_32

-png_pass_start_col(int pass)

-{

-   int x, y;

-   ++pass;

-   for (x=0; x<8; ++x) for (y=0; y<8; ++y) if (adam7[y][x] == pass)

-      return x;

-   return 0xf;

-}

-

-static int

-png_pass_row_shift(int pass)

-{

-   int x, y, base=(-1), inc=8;

-   ++pass;

-   for (y=0; y<8; ++y) for (x=0; x<8; ++x) if (adam7[y][x] == pass)

-   {

-      if (base == (-1))

-         base = y;

-      else if (base == y)

-         {}

-      else if (inc == y-base)

-         base=y;

-      else if (inc == 8)

-         inc = y-base, base=y;

-      else if (inc != y-base)

-         return 0xff; /* error - more than one 'inc' value! */

-   }

-

-   if (base == (-1)) return 0xfe; /* error - no row in pass! */

-

-   /* The shift is always 1, 2 or 3 - no pass has all the rows! */

-   switch (inc)

-   {

-case 2: return 1;

-case 4: return 2;

-case 8: return 3;

-default: break;

-   }

-

-   /* error - unrecognized 'inc' */

-   return (inc << 8) + 0xfd;

-}

-

-static int

-png_pass_col_shift(int pass)

-{

-   int x, y, base=(-1), inc=8;

-   ++pass;

-   for (x=0; x<8; ++x) for (y=0; y<8; ++y) if (adam7[y][x] == pass)

-   {

-      if (base == (-1))

-         base = x;

-      else if (base == x)

-         {}

-      else if (inc == x-base)

-         base=x;

-      else if (inc == 8)

-         inc = x-base, base=x;

-      else if (inc != x-base)

-         return 0xff; /* error - more than one 'inc' value! */

-   }

-

-   if (base == (-1)) return 0xfe; /* error - no row in pass! */

-

-   /* The shift is always 1, 2 or 3 - no pass has all the rows! */

-   switch (inc)

-   {

-case 1: return 0; /* pass 7 has all the columns */

-case 2: return 1;

-case 4: return 2;

-case 8: return 3;

-default: break;

-   }

-

-   /* error - unrecognized 'inc' */

-   return (inc << 8) + 0xfd;

-}

-

-static png_uint_32

-png_row_from_pass_row(png_uint_32 yIn, int pass)

-{

-   /* By examination of the array: */

-   switch (pass)

-   {

-case 0: return yIn * 8;

-case 1: return yIn * 8;

-case 2: return yIn * 8 + 4;

-case 3: return yIn * 4;

-case 4: return yIn * 4 + 2;

-case 5: return yIn * 2;

-case 6: return yIn * 2 + 1;

-default: break;

-   }

-

-   return 0xff; /* bad pass number */

-}

-

-static png_uint_32

-png_col_from_pass_col(png_uint_32 xIn, int pass)

-{

-   /* By examination of the array: */

-   switch (pass)

-   {

-case 0: return xIn * 8;

-case 1: return xIn * 8 + 4;

-case 2: return xIn * 4;

-case 3: return xIn * 4 + 2;

-case 4: return xIn * 2;

-case 5: return xIn * 2 + 1;

-case 6: return xIn;

-default: break;

-   }

-

-   return 0xff; /* bad pass number */

-}

-

-static int

-png_row_in_interlace_pass(png_uint_32 y, int pass)

-{

-   /* Is row 'y' in pass 'pass'? */

-   int x;

-   y &= 7;

-   ++pass;

-   for (x=0; x<8; ++x) if (adam7[y][x] == pass)

-      return 1;

-

-   return 0;

-}

-

-static int

-png_col_in_interlace_pass(png_uint_32 x, int pass)

-{

-   /* Is column 'x' in pass 'pass'? */

-   int y;

-   x &= 7;

-   ++pass;

-   for (y=0; y<8; ++y) if (adam7[y][x] == pass)

-      return 1;

-

-   return 0;

-}

-

-static png_uint_32

-png_pass_rows(png_uint_32 height, int pass)

-{

-   png_uint_32 tiles = height>>3;

-   png_uint_32 rows = 0;

-   unsigned int x, y;

-

-   height &= 7;

-   ++pass;

-   for (y=0; y<8; ++y) for (x=0; x<8; ++x) if (adam7[y][x] == pass)

-   {

-      rows += tiles;

-      if (y < height) ++rows;

-      break; /* i.e. break the 'x', column, loop. */

-   }

-

-   return rows;

-}

-

-static png_uint_32

-png_pass_cols(png_uint_32 width, int pass)

-{

-   png_uint_32 tiles = width>>3;

-   png_uint_32 cols = 0;

-   unsigned int x, y;

-

-   width &= 7;

-   ++pass;

-   for (x=0; x<8; ++x) for (y=0; y<8; ++y) if (adam7[y][x] == pass)

-   {

-      cols += tiles;

-      if (x < width) ++cols;

-      break; /* i.e. break the 'y', row, loop. */

-   }

-

-   return cols;

-}

-

-static void

-perform_interlace_macro_validation(void)

-{

-   /* The macros to validate, first those that depend only on pass:

-    *

-    * PNG_PASS_START_ROW(pass)

-    * PNG_PASS_START_COL(pass)

-    * PNG_PASS_ROW_SHIFT(pass)

-    * PNG_PASS_COL_SHIFT(pass)

-    */

-   int pass;

-

-   for (pass=0; pass<7; ++pass)

-   {

-      png_uint_32 m, f, v;

-

-      m = PNG_PASS_START_ROW(pass);

-      f = png_pass_start_row(pass);

-      if (m != f)

-      {

-         fprintf(stderr, "PNG_PASS_START_ROW(%d) = %u != %x\n", pass, m, f);

-         exit(1);

-      }

-

-      m = PNG_PASS_START_COL(pass);

-      f = png_pass_start_col(pass);

-      if (m != f)

-      {

-         fprintf(stderr, "PNG_PASS_START_COL(%d) = %u != %x\n", pass, m, f);

-         exit(1);

-      }

-

-      m = PNG_PASS_ROW_SHIFT(pass);

-      f = png_pass_row_shift(pass);

-      if (m != f)

-      {

-         fprintf(stderr, "PNG_PASS_ROW_SHIFT(%d) = %u != %x\n", pass, m, f);

-         exit(1);

-      }

-

-      m = PNG_PASS_COL_SHIFT(pass);

-      f = png_pass_col_shift(pass);

-      if (m != f)

-      {

-         fprintf(stderr, "PNG_PASS_COL_SHIFT(%d) = %u != %x\n", pass, m, f);

-         exit(1);

-      }

-

-      /* Macros that depend on the image or sub-image height too:

-       *

-       * PNG_PASS_ROWS(height, pass)

-       * PNG_PASS_COLS(width, pass)

-       * PNG_ROW_FROM_PASS_ROW(yIn, pass)

-       * PNG_COL_FROM_PASS_COL(xIn, pass)

-       * PNG_ROW_IN_INTERLACE_PASS(y, pass)

-       * PNG_COL_IN_INTERLACE_PASS(x, pass)

-       */

-      for (v=0;;)

-      {

-         /* First the base 0 stuff: */

-         m = PNG_ROW_FROM_PASS_ROW(v, pass);

-         f = png_row_from_pass_row(v, pass);

-         if (m != f)

-         {

-            fprintf(stderr, "PNG_ROW_FROM_PASS_ROW(%u, %d) = %u != %x\n",

-               v, pass, m, f);

-            exit(1);

-         }

-

-         m = PNG_COL_FROM_PASS_COL(v, pass);

-         f = png_col_from_pass_col(v, pass);

-         if (m != f)

-         {

-            fprintf(stderr, "PNG_COL_FROM_PASS_COL(%u, %d) = %u != %x\n",

-               v, pass, m, f);

-            exit(1);

-         }

-

-         m = PNG_ROW_IN_INTERLACE_PASS(v, pass);

-         f = png_row_in_interlace_pass(v, pass);

-         if (m != f)

-         {

-            fprintf(stderr, "PNG_ROW_IN_INTERLACE_PASS(%u, %d) = %u != %x\n",

-               v, pass, m, f);

-            exit(1);

-         }

-

-         m = PNG_COL_IN_INTERLACE_PASS(v, pass);

-         f = png_col_in_interlace_pass(v, pass);

-         if (m != f)

-         {

-            fprintf(stderr, "PNG_COL_IN_INTERLACE_PASS(%u, %d) = %u != %x\n",

-               v, pass, m, f);

-            exit(1);

-         }

-

-         /* Then the base 1 stuff: */

-         ++v;

-         m = PNG_PASS_ROWS(v, pass);

-         f = png_pass_rows(v, pass);

-         if (m != f)

-         {

-            fprintf(stderr, "PNG_PASS_ROWS(%u, %d) = %u != %x\n",

-               v, pass, m, f);

-            exit(1);

-         }

-

-         m = PNG_PASS_COLS(v, pass);

-         f = png_pass_cols(v, pass);

-         if (m != f)

-         {

-            fprintf(stderr, "PNG_PASS_COLS(%u, %d) = %u != %x\n",

-               v, pass, m, f);

-            exit(1);

-         }

-

-         /* Move to the next v - the stepping algorithm starts skipping

-          * values above 1024.

-          */

-         if (v > 1024)

-         {

-            if (v == PNG_UINT_31_MAX)

-               break;

-

-            v = (v << 1) ^ v;

-            if (v >= PNG_UINT_31_MAX)

-               v = PNG_UINT_31_MAX-1;

-         }

-      }

-   }

-}

-

-/* Test color encodings. These values are back-calculated from the published

- * chromaticities.  The values are accurate to about 14 decimal places; 15 are

- * given.  These values are much more accurate than the ones given in the spec,

- * which typically don't exceed 4 decimal places.  This allows testing of the

- * libpng code to its theoretical accuracy of 4 decimal places.  (If pngvalid

- * used the published errors the 'slack' permitted would have to be +/-.5E-4 or

- * more.)

- *

- * The png_modifier code assumes that encodings[0] is sRGB and treats it

- * specially: do not change the first entry in this list!

- */

-static PNG_CONST color_encoding test_encodings[] =

-{

-/* sRGB: must be first in this list! */

-/*gamma:*/ { 1/2.2,

-/*red:  */ { 0.412390799265959, 0.212639005871510, 0.019330818715592 },

-/*green:*/ { 0.357584339383878, 0.715168678767756, 0.119194779794626 },

-/*blue: */ { 0.180480788401834, 0.072192315360734, 0.950532152249660} },

-/* Kodak ProPhoto (wide gamut) */

-/*gamma:*/ { 1/1.6 /*approximate: uses 1.8 power law compared to sRGB 2.4*/,

-/*red:  */ { 0.797760489672303, 0.288071128229293, 0.000000000000000 },

-/*green:*/ { 0.135185837175740, 0.711843217810102, 0.000000000000000 },

-/*blue: */ { 0.031349349581525, 0.000085653960605, 0.825104602510460} },

-/* Adobe RGB (1998) */

-/*gamma:*/ { 1/(2+51./256),

-/*red:  */ { 0.576669042910131, 0.297344975250536, 0.027031361386412 },

-/*green:*/ { 0.185558237906546, 0.627363566255466, 0.070688852535827 },

-/*blue: */ { 0.188228646234995, 0.075291458493998, 0.991337536837639} },

-/* Adobe Wide Gamut RGB */

-/*gamma:*/ { 1/(2+51./256),

-/*red:  */ { 0.716500716779386, 0.258728243040113, 0.000000000000000 },

-/*green:*/ { 0.101020574397477, 0.724682314948566, 0.051211818965388 },

-/*blue: */ { 0.146774385252705, 0.016589442011321, 0.773892783545073} },

-};

-

-/* signal handler

- *

- * This attempts to trap signals and escape without crashing.  It needs a

- * context pointer so that it can throw an exception (call longjmp) to recover

- * from the condition; this is handled by making the png_modifier used by 'main'

- * into a global variable.

- */

-static png_modifier pm;

-

-static void signal_handler(int signum)

-{

-

-   size_t pos = 0;

-   char msg[64];

-

-   pos = safecat(msg, sizeof msg, pos, "caught signal: ");

-

-   switch (signum)

-   {

-      case SIGABRT:

-         pos = safecat(msg, sizeof msg, pos, "abort");

-         break;

-

-      case SIGFPE:

-         pos = safecat(msg, sizeof msg, pos, "floating point exception");

-         break;

-

-      case SIGILL:

-         pos = safecat(msg, sizeof msg, pos, "illegal instruction");

-         break;

-

-      case SIGINT:

-         pos = safecat(msg, sizeof msg, pos, "interrupt");

-         break;

-

-      case SIGSEGV:

-         pos = safecat(msg, sizeof msg, pos, "invalid memory access");

-         break;

-

-      case SIGTERM:

-         pos = safecat(msg, sizeof msg, pos, "termination request");

-         break;

-

-      default:

-         pos = safecat(msg, sizeof msg, pos, "unknown ");

-         pos = safecatn(msg, sizeof msg, pos, signum);

-         break;

-   }

-

-   store_log(&pm.this, NULL/*png_structp*/, msg, 1/*error*/);

-

-   /* And finally throw an exception so we can keep going, unless this is

-    * SIGTERM in which case stop now.

-    */

-   if (signum != SIGTERM)

-   {

-      struct exception_context *the_exception_context =

-         &pm.this.exception_context;

-

-      Throw &pm.this;

-   }

-

-   else

-      exit(1);

-}

-

-/* main program */

-int main(int argc, PNG_CONST char **argv)

-{

-   volatile int summary = 1;  /* Print the error summary at the end */

-   volatile int memstats = 0; /* Print memory statistics at the end */

-

-   /* Create the given output file on success: */

-   PNG_CONST char *volatile touch = NULL;

-

-   /* This is an array of standard gamma values (believe it or not I've seen

-    * every one of these mentioned somewhere.)

-    *

-    * In the following list the most useful values are first!

-    */

-   static double

-      gammas[]={2.2, 1.0, 2.2/1.45, 1.8, 1.5, 2.4, 2.5, 2.62, 2.9};

-

-   /* This records the command and arguments: */

-   size_t cp = 0;

-   char command[1024];

-

-   anon_context(&pm.this);

-

-   /* Add appropriate signal handlers, just the ANSI specified ones: */

-   signal(SIGABRT, signal_handler);

-   signal(SIGFPE, signal_handler);

-   signal(SIGILL, signal_handler);

-   signal(SIGINT, signal_handler);

-   signal(SIGSEGV, signal_handler);

-   signal(SIGTERM, signal_handler);

-

-#ifdef HAVE_FEENABLEEXCEPT

-   /* Only required to enable FP exceptions on platforms where they start off

-    * disabled; this is not necessary but if it is not done pngvalid will likely

-    * end up ignoring FP conditions that other platforms fault.

-    */

-   feenableexcept(FE_DIVBYZERO | FE_INVALID | FE_OVERFLOW);

-#endif

-

-   modifier_init(&pm);

-

-   /* Preallocate the image buffer, because we know how big it needs to be,

-    * note that, for testing purposes, it is deliberately mis-aligned by tag

-    * bytes either side.  All rows have an additional five bytes of padding for

-    * overwrite checking.

-    */

-   store_ensure_image(&pm.this, NULL, 2, TRANSFORM_ROWMAX, TRANSFORM_HEIGHTMAX);

-

-   /* Don't give argv[0], it's normally some horrible libtool string: */

-   cp = safecat(command, sizeof command, cp, "pngvalid");

-

-   /* Default to error on warning: */

-   pm.this.treat_warnings_as_errors = 1;

-

-   /* Store the test gammas */

-   pm.gammas = gammas;

-   pm.ngammas = (sizeof gammas) / (sizeof gammas[0]);

-   pm.ngamma_tests = 0; /* default to off */

-

-   /* And the test encodings */

-   pm.encodings = test_encodings;

-   pm.nencodings = (sizeof test_encodings) / (sizeof test_encodings[0]);

-

-   pm.sbitlow = 8U; /* because libpng doesn't do sBIT below 8! */

-   /* The following allows results to pass if they correspond to anything in the

-    * transformed range [input-.5,input+.5]; this is is required because of the

-    * way libpng treates the 16_TO_8 flag when building the gamma tables.

-    *

-    * TODO: review this

-    */

-   pm.use_input_precision_16to8 = 1U;

-

-   /* Some default values (set the behavior for 'make check' here).

-    * These values simply control the maximum error permitted in the gamma

-    * transformations.  The practial limits for human perception are described

-    * below (the setting for maxpc16), however for 8 bit encodings it isn't

-    * possible to meet the accepted capabilities of human vision - i.e. 8 bit

-    * images can never be good enough, regardless of encoding.

-    */

-   pm.maxout8 = .1;     /* Arithmetic error in *encoded* value */

-   pm.maxabs8 = .00005; /* 1/20000 */

-   pm.maxcalc8 = .004;  /* +/-1 in 8 bits for compose errors */

-   pm.maxpc8 = .499;    /* I.e., .499% fractional error */

-   pm.maxout16 = .499;  /* Error in *encoded* value */

-   pm.maxabs16 = .00005;/* 1/20000 */

-   pm.maxcalc16 =.000015;/* +/-1 in 16 bits for compose errors */

-

-   /* NOTE: this is a reasonable perceptual limit. We assume that humans can

-    * perceive light level differences of 1% over a 100:1 range, so we need to

-    * maintain 1 in 10000 accuracy (in linear light space), which is what the

-    * following guarantees.  It also allows significantly higher errors at

-    * higher 16 bit values, which is important for performance.  The actual

-    * maximum 16 bit error is about +/-1.9 in the fixed point implementation but

-    * this is only allowed for values >38149 by the following:

-    */

-   pm.maxpc16 = .005;   /* I.e., 1/200% - 1/20000 */

-

-   /* Now parse the command line options. */

-   while (--argc >= 1)

-   {

-      int catmore = 0; /* Set if the argument has an argument. */

-

-      /* Record each argument for posterity: */

-      cp = safecat(command, sizeof command, cp, " ");

-      cp = safecat(command, sizeof command, cp, *++argv);

-

-      if (strcmp(*argv, "-v") == 0)

-         pm.this.verbose = 1;

-

-      else if (strcmp(*argv, "-l") == 0)

-         pm.log = 1;

-

-      else if (strcmp(*argv, "-q") == 0)

-         summary = pm.this.verbose = pm.log = 0;

-

-      else if (strcmp(*argv, "-w") == 0)

-         pm.this.treat_warnings_as_errors = 0;

-

-      else if (strcmp(*argv, "--speed") == 0)

-         pm.this.speed = 1, pm.ngamma_tests = pm.ngammas, pm.test_standard = 0,

-            summary = 0;

-

-      else if (strcmp(*argv, "--memory") == 0)

-         memstats = 1;

-

-      else if (strcmp(*argv, "--size") == 0)

-         pm.test_size = 1;

-

-      else if (strcmp(*argv, "--nosize") == 0)

-         pm.test_size = 0;

-

-      else if (strcmp(*argv, "--standard") == 0)

-         pm.test_standard = 1;

-

-      else if (strcmp(*argv, "--nostandard") == 0)

-         pm.test_standard = 0;

-

-      else if (strcmp(*argv, "--transform") == 0)

-         pm.test_transform = 1;

-

-      else if (strcmp(*argv, "--notransform") == 0)

-         pm.test_transform = 0;

-

-#ifdef PNG_READ_TRANSFORMS_SUPPORTED

-      else if (strncmp(*argv, "--transform-disable=",

-         sizeof "--transform-disable") == 0)

-         {

-         pm.test_transform = 1;

-         transform_disable(*argv + sizeof "--transform-disable");

-         }

-

-      else if (strncmp(*argv, "--transform-enable=",

-         sizeof "--transform-enable") == 0)

-         {

-         pm.test_transform = 1;

-         transform_enable(*argv + sizeof "--transform-enable");

-         }

-#endif /* PNG_READ_TRANSFORMS_SUPPORTED */

-

-      else if (strcmp(*argv, "--gamma") == 0)

-         {

-         /* Just do two gamma tests here (2.2 and linear) for speed: */

-         pm.ngamma_tests = 2U;

-         pm.test_gamma_threshold = 1;

-         pm.test_gamma_transform = 1;

-         pm.test_gamma_sbit = 1;

-         pm.test_gamma_scale16 = 1;

-         pm.test_gamma_background = 1;

-         pm.test_gamma_alpha_mode = 1;

-         }

-

-      else if (strcmp(*argv, "--nogamma") == 0)

-         pm.ngamma_tests = 0;

-

-      else if (strcmp(*argv, "--gamma-threshold") == 0)

-         pm.ngamma_tests = 2U, pm.test_gamma_threshold = 1;

-

-      else if (strcmp(*argv, "--nogamma-threshold") == 0)

-         pm.test_gamma_threshold = 0;

-

-      else if (strcmp(*argv, "--gamma-transform") == 0)

-         pm.ngamma_tests = 2U, pm.test_gamma_transform = 1;

-

-      else if (strcmp(*argv, "--nogamma-transform") == 0)

-         pm.test_gamma_transform = 0;

-

-      else if (strcmp(*argv, "--gamma-sbit") == 0)

-         pm.ngamma_tests = 2U, pm.test_gamma_sbit = 1;

-

-      else if (strcmp(*argv, "--nogamma-sbit") == 0)

-         pm.test_gamma_sbit = 0;

-

-      else if (strcmp(*argv, "--gamma-16-to-8") == 0)

-         pm.ngamma_tests = 2U, pm.test_gamma_scale16 = 1;

-

-      else if (strcmp(*argv, "--nogamma-16-to-8") == 0)

-         pm.test_gamma_scale16 = 0;

-

-      else if (strcmp(*argv, "--gamma-background") == 0)

-         pm.ngamma_tests = 2U, pm.test_gamma_background = 1;

-

-      else if (strcmp(*argv, "--nogamma-background") == 0)

-         pm.test_gamma_background = 0;

-

-      else if (strcmp(*argv, "--gamma-alpha-mode") == 0)

-         pm.ngamma_tests = 2U, pm.test_gamma_alpha_mode = 1;

-

-      else if (strcmp(*argv, "--nogamma-alpha-mode") == 0)

-         pm.test_gamma_alpha_mode = 0;

-

-      else if (strcmp(*argv, "--expand16") == 0)

-         pm.test_gamma_expand16 = 1;

-

-      else if (strcmp(*argv, "--noexpand16") == 0)

-         pm.test_gamma_expand16 = 0;

-

-      else if (strcmp(*argv, "--more-gammas") == 0)

-         pm.ngamma_tests = 3U;

-

-      else if (strcmp(*argv, "--all-gammas") == 0)

-         pm.ngamma_tests = pm.ngammas;

-

-      else if (strcmp(*argv, "--progressive-read") == 0)

-         pm.this.progressive = 1;

-

-      else if (strcmp(*argv, "--use-update-info") == 0)

-         ++pm.use_update_info; /* Can call multiple times */

-

-      else if (strcmp(*argv, "--interlace") == 0)

-         pm.interlace_type = PNG_INTERLACE_ADAM7;

-

-      else if (strcmp(*argv, "--use-input-precision") == 0)

-         pm.use_input_precision = 1;

-

-      else if (strcmp(*argv, "--calculations-use-input-precision") == 0)

-         pm.calculations_use_input_precision = 1;

-

-      else if (strcmp(*argv, "--assume-16-bit-calculations") == 0)

-         pm.assume_16_bit_calculations = 1;

-

-      else if (strcmp(*argv, "--calculations-follow-bit-depth") == 0)

-         pm.calculations_use_input_precision =

-            pm.assume_16_bit_calculations = 0;

-

-      else if (strcmp(*argv, "--exhaustive") == 0)

-         pm.test_exhaustive = 1;

-

-      else if (argc > 1 && strcmp(*argv, "--sbitlow") == 0)

-         --argc, pm.sbitlow = (png_byte)atoi(*++argv), catmore = 1;

-

-      else if (argc > 1 && strcmp(*argv, "--touch") == 0)

-         --argc, touch = *++argv, catmore = 1;

-

-      else if (argc > 1 && strncmp(*argv, "--max", 5) == 0)

-      {

-         --argc;

-

-         if (strcmp(5+*argv, "abs8") == 0)

-            pm.maxabs8 = atof(*++argv);

-

-         else if (strcmp(5+*argv, "abs16") == 0)

-            pm.maxabs16 = atof(*++argv);

-

-         else if (strcmp(5+*argv, "calc8") == 0)

-            pm.maxcalc8 = atof(*++argv);

-

-         else if (strcmp(5+*argv, "calc16") == 0)

-            pm.maxcalc16 = atof(*++argv);

-

-         else if (strcmp(5+*argv, "out8") == 0)

-            pm.maxout8 = atof(*++argv);

-

-         else if (strcmp(5+*argv, "out16") == 0)

-            pm.maxout16 = atof(*++argv);

-

-         else if (strcmp(5+*argv, "pc8") == 0)

-            pm.maxpc8 = atof(*++argv);

-

-         else if (strcmp(5+*argv, "pc16") == 0)

-            pm.maxpc16 = atof(*++argv);

-

-         else

-         {

-            fprintf(stderr, "pngvalid: %s: unknown 'max' option\n", *argv);

-            exit(1);

-         }

-

-         catmore = 1;

-      }

-

-      else if (strcmp(*argv, "--log8") == 0)

-         --argc, pm.log8 = atof(*++argv), catmore = 1;

-

-      else if (strcmp(*argv, "--log16") == 0)

-         --argc, pm.log16 = atof(*++argv), catmore = 1;

-

-      else

-      {

-         fprintf(stderr, "pngvalid: %s: unknown argument\n", *argv);

-         exit(1);

-      }

-

-      if (catmore) /* consumed an extra *argv */

-      {

-         cp = safecat(command, sizeof command, cp, " ");

-         cp = safecat(command, sizeof command, cp, *argv);

-      }

-   }

-

-   /* If pngvalid is run with no arguments default to a reasonable set of the

-    * tests.

-    */

-   if (pm.test_standard == 0 && pm.test_size == 0 && pm.test_transform == 0 &&

-      pm.ngamma_tests == 0)

-   {

-      /* Make this do all the tests done in the test shell scripts with the same

-       * parameters, where possible.  The limitation is that all the progressive

-       * read and interlace stuff has to be done in separate runs, so only the

-       * basic 'standard' and 'size' tests are done.

-       */

-      pm.test_standard = 1;

-      pm.test_size = 1;

-      pm.test_transform = 1;

-      pm.ngamma_tests = 2U;

-   }

-

-   if (pm.ngamma_tests > 0 &&

-      pm.test_gamma_threshold == 0 && pm.test_gamma_transform == 0 &&

-      pm.test_gamma_sbit == 0 && pm.test_gamma_scale16 == 0 &&

-      pm.test_gamma_background == 0 && pm.test_gamma_alpha_mode == 0)

-   {

-      pm.test_gamma_threshold = 1;

-      pm.test_gamma_transform = 1;

-      pm.test_gamma_sbit = 1;

-      pm.test_gamma_scale16 = 1;

-      pm.test_gamma_background = 1;

-      pm.test_gamma_alpha_mode = 1;

-   }

-

-   else if (pm.ngamma_tests == 0)

-   {

-      /* Nothing to test so turn everything off: */

-      pm.test_gamma_threshold = 0;

-      pm.test_gamma_transform = 0;

-      pm.test_gamma_sbit = 0;

-      pm.test_gamma_scale16 = 0;

-      pm.test_gamma_background = 0;

-      pm.test_gamma_alpha_mode = 0;

-   }

-

-   Try

-   {

-      /* Make useful base images */

-      make_transform_images(&pm.this);

-

-      /* Perform the standard and gamma tests. */

-      if (pm.test_standard)

-      {

-         perform_interlace_macro_validation();

-         perform_formatting_test(&pm.this);

-         perform_standard_test(&pm);

-         perform_error_test(&pm);

-      }

-

-      /* Various oddly sized images: */

-      if (pm.test_size)

-      {

-         make_size_images(&pm.this);

-         perform_size_test(&pm);

-      }

-

-#ifdef PNG_READ_TRANSFORMS_SUPPORTED

-      /* Combinatorial transforms: */

-      if (pm.test_transform)

-         perform_transform_test(&pm);

-#endif /* PNG_READ_TRANSFORMS_SUPPORTED */

-

-#ifdef PNG_READ_GAMMA_SUPPORTED

-      if (pm.ngamma_tests > 0)

-         perform_gamma_test(&pm, summary);

-#endif

-   }

-

-   Catch_anonymous

-   {

-      fprintf(stderr, "pngvalid: test aborted (probably failed in cleanup)\n");

-      if (!pm.this.verbose)

-      {

-         if (pm.this.error[0] != 0)

-            fprintf(stderr, "pngvalid: first error: %s\n", pm.this.error);

-

-         fprintf(stderr, "pngvalid: run with -v to see what happened\n");

-      }

-      exit(1);

-   }

-

-   if (summary)

-   {

-      printf("%s: %s (%s point arithmetic)\n",

-         (pm.this.nerrors || (pm.this.treat_warnings_as_errors &&

-            pm.this.nwarnings)) ? "FAIL" : "PASS",

-         command,

-#if defined(PNG_FLOATING_ARITHMETIC_SUPPORTED) || PNG_LIBPNG_VER < 10500

-         "floating"

-#else

-         "fixed"

-#endif

-         );

-   }

-

-   if (memstats)

-   {

-      printf("Allocated memory statistics (in bytes):\n"

-         "\tread  %lu maximum single, %lu peak, %lu total\n"

-         "\twrite %lu maximum single, %lu peak, %lu total\n",

-         (unsigned long)pm.this.read_memory_pool.max_max,

-         (unsigned long)pm.this.read_memory_pool.max_limit,

-         (unsigned long)pm.this.read_memory_pool.max_total,

-         (unsigned long)pm.this.write_memory_pool.max_max,

-         (unsigned long)pm.this.write_memory_pool.max_limit,

-         (unsigned long)pm.this.write_memory_pool.max_total);

-   }

-

-   /* Do this here to provoke memory corruption errors in memory not directly

-    * allocated by libpng - not a complete test, but better than nothing.

-    */

-   store_delete(&pm.this);

-

-   /* Error exit if there are any errors, and maybe if there are any

-    * warnings.

-    */

-   if (pm.this.nerrors || (pm.this.treat_warnings_as_errors &&

-       pm.this.nwarnings))

-   {

-      if (!pm.this.verbose)

-         fprintf(stderr, "pngvalid: %s\n", pm.this.error);

-

-      fprintf(stderr, "pngvalid: %d errors, %d warnings\n", pm.this.nerrors,

-          pm.this.nwarnings);

-

-      exit(1);

-   }

-

-   /* Success case. */

-   if (touch != NULL)

-   {

-      FILE *fsuccess = fopen(touch, "wt");

-

-      if (fsuccess != NULL)

-      {

-         int error = 0;

-         fprintf(fsuccess, "PNG validation succeeded\n");

-         fflush(fsuccess);

-         error = ferror(fsuccess);

-

-         if (fclose(fsuccess) || error)

-         {

-            fprintf(stderr, "%s: write failed\n", touch);

-            exit(1);

-         }

-      }

-   }

-

-   return 0;

-}

+
+/* pngvalid.c - validate libpng by constructing then reading png files.
+ *
+ * Last changed in libpng 1.5.8 [%RDATE%]
+ * Copyright (c) 2012 Glenn Randers-Pehrson
+ * Written by John Cunningham Bowler
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ *
+ * NOTES:
+ *   This is a C program that is intended to be linked against libpng.  It
+ *   generates bitmaps internally, stores them as PNG files (using the
+ *   sequential write code) then reads them back (using the sequential
+ *   read code) and validates that the result has the correct data.
+ *
+ *   The program can be modified and extended to test the correctness of
+ *   transformations performed by libpng.
+ */
+
+#define _POSIX_SOURCE 1
+#define _ISOC99_SOURCE 1 /* For floating point */
+#define _GNU_SOURCE 1 /* For the floating point exception extension */
+
+#include <signal.h>
+
+#ifdef HAVE_FEENABLEEXCEPT
+#  include <fenv.h>
+#endif
+
+/* Define the following to use this test against your installed libpng, rather
+ * than the one being built here:
+ */
+#ifdef PNG_FREESTANDING_TESTS
+#  include <png.h>
+#else
+#  include "../../png.h"
+#endif
+
+#if PNG_LIBPNG_VER < 10500
+/* This deliberately lacks the PNG_CONST. */
+typedef png_byte *png_const_bytep;
+
+/* This is copied from 1.5.1 png.h: */
+#define PNG_INTERLACE_ADAM7_PASSES 7
+#define PNG_PASS_START_ROW(pass) (((1U&~(pass))<<(3-((pass)>>1)))&7)
+#define PNG_PASS_START_COL(pass) (((1U& (pass))<<(3-(((pass)+1)>>1)))&7)
+#define PNG_PASS_ROW_SHIFT(pass) ((pass)>2?(8-(pass))>>1:3)
+#define PNG_PASS_COL_SHIFT(pass) ((pass)>1?(7-(pass))>>1:3)
+#define PNG_PASS_ROWS(height, pass) (((height)+(((1<<PNG_PASS_ROW_SHIFT(pass))\
+   -1)-PNG_PASS_START_ROW(pass)))>>PNG_PASS_ROW_SHIFT(pass))
+#define PNG_PASS_COLS(width, pass) (((width)+(((1<<PNG_PASS_COL_SHIFT(pass))\
+   -1)-PNG_PASS_START_COL(pass)))>>PNG_PASS_COL_SHIFT(pass))
+#define PNG_ROW_FROM_PASS_ROW(yIn, pass) \
+   (((yIn)<<PNG_PASS_ROW_SHIFT(pass))+PNG_PASS_START_ROW(pass))
+#define PNG_COL_FROM_PASS_COL(xIn, pass) \
+   (((xIn)<<PNG_PASS_COL_SHIFT(pass))+PNG_PASS_START_COL(pass))
+#define PNG_PASS_MASK(pass,off) ( \
+   ((0x110145AFU>>(((7-(off))-(pass))<<2)) & 0xFU) | \
+   ((0x01145AF0U>>(((7-(off))-(pass))<<2)) & 0xF0U))
+#define PNG_ROW_IN_INTERLACE_PASS(y, pass) \
+   ((PNG_PASS_MASK(pass,0) >> ((y)&7)) & 1)
+#define PNG_COL_IN_INTERLACE_PASS(x, pass) \
+   ((PNG_PASS_MASK(pass,1) >> ((x)&7)) & 1)
+
+/* These are needed too for the default build: */
+#define PNG_WRITE_16BIT_SUPPORTED
+#define PNG_READ_16BIT_SUPPORTED
+
+/* This comes from pnglibconf.h afer 1.5: */
+#define PNG_FP_1 100000
+#define PNG_GAMMA_THRESHOLD_FIXED\
+   ((png_fixed_point)(PNG_GAMMA_THRESHOLD * PNG_FP_1))
+#endif
+
+#include "zlib.h"   /* For crc32 */
+
+#include <float.h>  /* For floating point constants */
+#include <stdlib.h> /* For malloc */
+#include <string.h> /* For memcpy, memset */
+#include <math.h>   /* For floor */
+
+/* Unused formal parameter errors are removed using the following macro which is
+ * expected to have no bad effects on performance.
+ */
+#ifndef UNUSED
+#  if defined(__GNUC__) || defined(_MSC_VER)
+#     define UNUSED(param) (void)param;
+#  else
+#     define UNUSED(param)
+#  endif
+#endif
+
+/***************************** EXCEPTION HANDLING *****************************/
+#include "../visupng/cexcept.h"
+
+#ifdef __cplusplus
+#  define this not_the_cpp_this
+#  define new not_the_cpp_new
+#  define voidcast(type, value) static_cast<type>(value)
+#else
+#  define voidcast(type, value) (value)
+#endif /* __cplusplus */
+
+struct png_store;
+define_exception_type(struct png_store*);
+
+/* The following are macros to reduce typing everywhere where the well known
+ * name 'the_exception_context' must be defined.
+ */
+#define anon_context(ps) struct exception_context *the_exception_context = \
+   &(ps)->exception_context
+#define context(ps,fault) anon_context(ps); png_store *fault
+
+/******************************* UTILITIES ************************************/
+/* Error handling is particularly problematic in production code - error
+ * handlers often themselves have bugs which lead to programs that detect
+ * minor errors crashing.  The following functions deal with one very
+ * common class of errors in error handlers - attempting to format error or
+ * warning messages into buffers that are too small.
+ */
+static size_t safecat(char *buffer, size_t bufsize, size_t pos,
+   PNG_CONST char *cat)
+{
+   while (pos < bufsize && cat != NULL && *cat != 0)
+      buffer[pos++] = *cat++;
+
+   if (pos >= bufsize)
+      pos = bufsize-1;
+
+   buffer[pos] = 0;
+   return pos;
+}
+
+static size_t safecatn(char *buffer, size_t bufsize, size_t pos, int n)
+{
+   char number[64];
+   sprintf(number, "%d", n);
+   return safecat(buffer, bufsize, pos, number);
+}
+
+#ifdef PNG_READ_TRANSFORMS_SUPPORTED
+static size_t safecatd(char *buffer, size_t bufsize, size_t pos, double d,
+    int precision)
+{
+   char number[64];
+   sprintf(number, "%.*f", precision, d);
+   return safecat(buffer, bufsize, pos, number);
+}
+#endif
+
+static PNG_CONST char invalid[] = "invalid";
+static PNG_CONST char sep[] = ": ";
+
+static PNG_CONST char *colour_types[8] =
+{
+   "grayscale", invalid, "truecolour", "indexed-colour",
+   "grayscale with alpha", invalid, "truecolour with alpha", invalid
+};
+
+/* Convert a double precision value to fixed point. */
+static png_fixed_point
+fix(double d)
+{
+   d = floor(d * PNG_FP_1 + .5);
+   return (png_fixed_point)d;
+}
+
+/* Generate random bytes.  This uses a boring repeatable algorithm and it
+ * is implemented here so that it gives the same set of numbers on every
+ * architecture.  It's a linear congruential generator (Knuth or Sedgewick
+ * "Algorithms") but it comes from the 'feedback taps' table in Horowitz and
+ * Hill, "The Art of Electronics".
+ */
+static void
+make_random_bytes(png_uint_32* seed, void* pv, size_t size)
+{
+   png_uint_32 u0 = seed[0], u1 = seed[1];
+   png_bytep bytes = voidcast(png_bytep, pv);
+
+   /* There are thirty three bits, the next bit in the sequence is bit-33 XOR
+    * bit-20.  The top 1 bit is in u1, the bottom 32 are in u0.
+    */
+   size_t i;
+   for (i=0; i<size; ++i)
+   {
+      /* First generate 8 new bits then shift them in at the end. */
+      png_uint_32 u = ((u0 >> (20-8)) ^ ((u1 << 7) | (u0 >> (32-7)))) & 0xff;
+      u1 <<= 8;
+      u1 |= u0 >> 24;
+      u0 <<= 8;
+      u0 |= u;
+      *bytes++ = (png_byte)u;
+   }
+
+   seed[0] = u0;
+   seed[1] = u1;
+}
+
+static void
+make_four_random_bytes(png_uint_32* seed, png_bytep bytes)
+{
+   make_random_bytes(seed, bytes, 4);
+}
+
+static void
+randomize(void *pv, size_t size)
+{
+   static png_uint_32 random_seed[2] = {0x56789abc, 0xd};
+   make_random_bytes(random_seed, pv, size);
+}
+
+#define RANDOMIZE(this) randomize(&(this), sizeof (this))
+
+static unsigned int
+random_mod(unsigned int max)
+{
+   unsigned int x;
+
+   RANDOMIZE(x);
+
+   return x % max; /* 0 .. max-1 */
+}
+
+static int
+random_choice(void)
+{
+   unsigned char x;
+
+   RANDOMIZE(x);
+
+   return x & 1;
+}
+
+/* A numeric ID based on PNG file characteristics.  The 'do_interlace' field
+ * simply records whether pngvalid did the interlace itself or whether it
+ * was done by libpng.  Width and height must be less than 256.  'palette' is an
+ * index of the palette to use for formats with a palette (0 otherwise.)
+ */
+#define FILEID(col, depth, palette, interlace, width, height, do_interlace) \
+   ((png_uint_32)((col) + ((depth)<<3) + ((palette)<<8) + ((interlace)<<13) + \
+    (((do_interlace)!=0)<<15) + ((width)<<16) + ((height)<<24)))
+
+#define COL_FROM_ID(id) ((png_byte)((id)& 0x7U))
+#define DEPTH_FROM_ID(id) ((png_byte)(((id) >> 3) & 0x1fU))
+#define PALETTE_FROM_ID(id) ((int)(((id) >> 8) & 0x1f))
+#define INTERLACE_FROM_ID(id) ((int)(((id) >> 13) & 0x3))
+#define DO_INTERLACE_FROM_ID(id) ((int)(((id)>>15) & 1))
+#define WIDTH_FROM_ID(id) (((id)>>16) & 0xff)
+#define HEIGHT_FROM_ID(id) (((id)>>24) & 0xff)
+
+/* Utility to construct a standard name for a standard image. */
+static size_t
+standard_name(char *buffer, size_t bufsize, size_t pos, png_byte colour_type,
+    int bit_depth, int npalette, int interlace_type,
+    png_uint_32 w, png_uint_32 h, int do_interlace)
+{
+   pos = safecat(buffer, bufsize, pos, colour_types[colour_type]);
+   if (npalette > 0)
+   {
+      pos = safecat(buffer, bufsize, pos, "[");
+      pos = safecatn(buffer, bufsize, pos, npalette);
+      pos = safecat(buffer, bufsize, pos, "]");
+   }
+   pos = safecat(buffer, bufsize, pos, " ");
+   pos = safecatn(buffer, bufsize, pos, bit_depth);
+   pos = safecat(buffer, bufsize, pos, " bit");
+
+   if (interlace_type != PNG_INTERLACE_NONE)
+   {
+      pos = safecat(buffer, bufsize, pos, " interlaced");
+      if (do_interlace)
+         pos = safecat(buffer, bufsize, pos, "(pngvalid)");
+      else
+         pos = safecat(buffer, bufsize, pos, "(libpng)");
+   }
+
+   if (w > 0 || h > 0)
+   {
+      pos = safecat(buffer, bufsize, pos, " ");
+      pos = safecatn(buffer, bufsize, pos, w);
+      pos = safecat(buffer, bufsize, pos, "x");
+      pos = safecatn(buffer, bufsize, pos, h);
+   }
+
+   return pos;
+}
+
+static size_t
+standard_name_from_id(char *buffer, size_t bufsize, size_t pos, png_uint_32 id)
+{
+   return standard_name(buffer, bufsize, pos, COL_FROM_ID(id),
+      DEPTH_FROM_ID(id), PALETTE_FROM_ID(id), INTERLACE_FROM_ID(id),
+      WIDTH_FROM_ID(id), HEIGHT_FROM_ID(id), DO_INTERLACE_FROM_ID(id));
+}
+
+/* Convenience API and defines to list valid formats.  Note that 16 bit read and
+ * write support is required to do 16 bit read tests (we must be able to make a
+ * 16 bit image to test!)
+ */
+#ifdef PNG_WRITE_16BIT_SUPPORTED
+#  define WRITE_BDHI 4
+#  ifdef PNG_READ_16BIT_SUPPORTED
+#     define READ_BDHI 4
+#     define DO_16BIT
+#  endif
+#else
+#  define WRITE_BDHI 3
+#endif
+#ifndef DO_16BIT
+#  define READ_BDHI 3
+#endif
+
+/* The following defines the number of different palettes to generate for
+ * each log bit depth of a colour type 3 standard image.
+ */
+#define PALETTE_COUNT(bit_depth) ((bit_depth) > 4 ? 1 : 16)
+
+static int
+next_format(png_bytep colour_type, png_bytep bit_depth, int* palette_number)
+{
+   if (*bit_depth == 0)
+   {
+      *colour_type = 0, *bit_depth = 1, *palette_number = 0;
+      return 1;
+   }
+
+   if (*colour_type == 3)
+   {
+      /* Add multiple palettes for colour type 3. */
+      if (++*palette_number < PALETTE_COUNT(*bit_depth))
+         return 1;
+
+      *palette_number = 0;
+   }
+
+   *bit_depth = (png_byte)(*bit_depth << 1);
+
+   /* Palette images are restricted to 8 bit depth */
+   if (*bit_depth <= 8
+#     ifdef DO_16BIT
+         || (*colour_type != 3 && *bit_depth <= 16)
+#     endif
+      )
+      return 1;
+
+   /* Move to the next color type, or return 0 at the end. */
+   switch (*colour_type)
+   {
+      case 0:
+         *colour_type = 2;
+         *bit_depth = 8;
+         return 1;
+
+      case 2:
+         *colour_type = 3;
+         *bit_depth = 1;
+         return 1;
+
+      case 3:
+         *colour_type = 4;
+         *bit_depth = 8;
+         return 1;
+
+      case 4:
+         *colour_type = 6;
+         *bit_depth = 8;
+         return 1;
+
+      default:
+         return 0;
+   }
+}
+
+#ifdef PNG_READ_TRANSFORMS_SUPPORTED
+static unsigned int
+sample(png_const_bytep row, png_byte colour_type, png_byte bit_depth,
+    png_uint_32 x, unsigned int sample_index)
+{
+   png_uint_32 bit_index, result;
+
+   /* Find a sample index for the desired sample: */
+   x *= bit_depth;
+   bit_index = x;
+
+   if ((colour_type & 1) == 0) /* !palette */
+   {
+      if (colour_type & 2)
+         bit_index *= 3;
+
+      if (colour_type & 4)
+         bit_index += x; /* Alpha channel */
+
+      /* Multiple channels; select one: */
+      if (colour_type & (2+4))
+         bit_index += sample_index * bit_depth;
+   }
+
+   /* Return the sample from the row as an integer. */
+   row += bit_index >> 3;
+   result = *row;
+
+   if (bit_depth == 8)
+      return result;
+
+   else if (bit_depth > 8)
+      return (result << 8) + *++row;
+
+   /* Less than 8 bits per sample. */
+   bit_index &= 7;
+   return (result >> (8-bit_index-bit_depth)) & ((1U<<bit_depth)-1);
+}
+#endif /* PNG_READ_TRANSFORMS_SUPPORTED */
+
+/* Copy a single pixel, of a given size, from one buffer to another -
+ * while this is basically bit addressed there is an implicit assumption
+ * that pixels 8 or more bits in size are byte aligned and that pixels
+ * do not otherwise cross byte boundaries.  (This is, so far as I know,
+ * universally true in bitmap computer graphics.  [JCB 20101212])
+ *
+ * NOTE: The to and from buffers may be the same.
+ */
+static void
+pixel_copy(png_bytep toBuffer, png_uint_32 toIndex,
+   png_const_bytep fromBuffer, png_uint_32 fromIndex, unsigned int pixelSize)
+{
+   /* Assume we can multiply by 'size' without overflow because we are
+    * just working in a single buffer.
+    */
+   toIndex *= pixelSize;
+   fromIndex *= pixelSize;
+   if (pixelSize < 8) /* Sub-byte */
+   {
+      /* Mask to select the location of the copied pixel: */
+      unsigned int destMask = ((1U<<pixelSize)-1) << (8-pixelSize-(toIndex&7));
+      /* The following read the entire pixels and clears the extra: */
+      unsigned int destByte = toBuffer[toIndex >> 3] & ~destMask;
+      unsigned int sourceByte = fromBuffer[fromIndex >> 3];
+
+      /* Don't rely on << or >> supporting '0' here, just in case: */
+      fromIndex &= 7;
+      if (fromIndex > 0) sourceByte <<= fromIndex;
+      if ((toIndex & 7) > 0) sourceByte >>= toIndex & 7;
+
+      toBuffer[toIndex >> 3] = (png_byte)(destByte | (sourceByte & destMask));
+   }
+   else /* One or more bytes */
+      memmove(toBuffer+(toIndex>>3), fromBuffer+(fromIndex>>3), pixelSize>>3);
+}
+
+/* Copy a complete row of pixels, taking into account potential partial
+ * bytes at the end.
+ */
+static void
+row_copy(png_bytep toBuffer, png_const_bytep fromBuffer, unsigned int bitWidth)
+{
+   memcpy(toBuffer, fromBuffer, bitWidth >> 3);
+
+   if ((bitWidth & 7) != 0)
+   {
+      unsigned int mask;
+
+      toBuffer += bitWidth >> 3;
+      fromBuffer += bitWidth >> 3;
+      /* The remaining bits are in the top of the byte, the mask is the bits to
+       * retain.
+       */
+      mask = 0xff >> (bitWidth & 7);
+      *toBuffer = (png_byte)((*toBuffer & mask) | (*fromBuffer & ~mask));
+   }
+}
+
+/* Compare pixels - they are assumed to start at the first byte in the
+ * given buffers.
+ */
+static int
+pixel_cmp(png_const_bytep pa, png_const_bytep pb, png_uint_32 bit_width)
+{
+#if PNG_LIBPNG_VER < 10506
+   if (memcmp(pa, pb, bit_width>>3) == 0)
+   {
+      png_uint_32 p;
+
+      if ((bit_width & 7) == 0) return 0;
+
+      /* Ok, any differences? */
+      p = pa[bit_width >> 3];
+      p ^= pb[bit_width >> 3];
+
+      if (p == 0) return 0;
+
+      /* There are, but they may not be significant, remove the bits
+       * after the end (the low order bits in PNG.)
+       */
+      bit_width &= 7;
+      p >>= 8-bit_width;
+
+      if (p == 0) return 0;
+   }
+#else
+   /* From libpng-1.5.6 the overwrite should be fixed, so compare the trailing
+    * bits too:
+    */
+   if (memcmp(pa, pb, (bit_width+7)>>3) == 0)
+      return 0;
+#endif
+
+   /* Return the index of the changed byte. */
+   {
+      png_uint_32 where = 0;
+
+      while (pa[where] == pb[where]) ++where;
+      return 1+where;
+   }
+}
+
+/*************************** BASIC PNG FILE WRITING ***************************/
+/* A png_store takes data from the sequential writer or provides data
+ * to the sequential reader.  It can also store the result of a PNG
+ * write for later retrieval.
+ */
+#define STORE_BUFFER_SIZE 500 /* arbitrary */
+typedef struct png_store_buffer
+{
+   struct png_store_buffer*  prev;    /* NOTE: stored in reverse order */
+   png_byte                  buffer[STORE_BUFFER_SIZE];
+} png_store_buffer;
+
+#define FILE_NAME_SIZE 64
+
+typedef struct store_palette_entry /* record of a single palette entry */
+{
+   png_byte red;
+   png_byte green;
+   png_byte blue;
+   png_byte alpha;
+} store_palette_entry, store_palette[256];
+
+typedef struct png_store_file
+{
+   struct png_store_file*  next;      /* as many as you like... */
+   char                    name[FILE_NAME_SIZE];
+   png_uint_32             id;        /* must be correct (see FILEID) */
+   png_size_t              datacount; /* In this (the last) buffer */
+   png_store_buffer        data;      /* Last buffer in file */
+   int                     npalette;  /* Number of entries in palette */
+   store_palette_entry*    palette;   /* May be NULL */
+} png_store_file;
+
+/* The following is a pool of memory allocated by a single libpng read or write
+ * operation.
+ */
+typedef struct store_pool
+{
+   struct png_store    *store;   /* Back pointer */
+   struct store_memory *list;    /* List of allocated memory */
+   png_byte             mark[4]; /* Before and after data */
+
+   /* Statistics for this run. */
+   png_alloc_size_t     max;     /* Maximum single allocation */
+   png_alloc_size_t     current; /* Current allocation */
+   png_alloc_size_t     limit;   /* Highest current allocation */
+   png_alloc_size_t     total;   /* Total allocation */
+
+   /* Overall statistics (retained across successive runs). */
+   png_alloc_size_t     max_max;
+   png_alloc_size_t     max_limit;
+   png_alloc_size_t     max_total;
+} store_pool;
+
+typedef struct png_store
+{
+   /* For cexcept.h exception handling - simply store one of these;
+    * the context is a self pointer but it may point to a different
+    * png_store (in fact it never does in this program.)
+    */
+   struct exception_context
+                      exception_context;
+
+   unsigned int       verbose :1;
+   unsigned int       treat_warnings_as_errors :1;
+   unsigned int       expect_error :1;
+   unsigned int       expect_warning :1;
+   unsigned int       saw_warning :1;
+   unsigned int       speed :1;
+   unsigned int       progressive :1; /* use progressive read */
+   unsigned int       validated :1;   /* used as a temporary flag */
+   int                nerrors;
+   int                nwarnings;
+   char               test[128]; /* Name of test */
+   char               error[256];
+
+   /* Read fields */
+   png_structp        pread;    /* Used to read a saved file */
+   png_infop          piread;
+   png_store_file*    current;  /* Set when reading */
+   png_store_buffer*  next;     /* Set when reading */
+   png_size_t         readpos;  /* Position in *next */
+   png_byte*          image;    /* Buffer for reading interlaced images */
+   png_size_t         cb_image; /* Size of this buffer */
+   png_size_t         cb_row;   /* Row size of the image(s) */
+   png_uint_32        image_h;  /* Number of rows in a single image */
+   store_pool         read_memory_pool;
+
+   /* Write fields */
+   png_store_file*    saved;
+   png_structp        pwrite;   /* Used when writing a new file */
+   png_infop          piwrite;
+   png_size_t         writepos; /* Position in .new */
+   char               wname[FILE_NAME_SIZE];
+   png_store_buffer   new;      /* The end of the new PNG file being written. */
+   store_pool         write_memory_pool;
+   store_palette_entry* palette;
+   int                  npalette;
+} png_store;
+
+/* Initialization and cleanup */
+static void
+store_pool_mark(png_bytep mark)
+{
+   static png_uint_32 store_seed[2] = { 0x12345678, 1};
+
+   make_four_random_bytes(store_seed, mark);
+}
+
+/* Use this for random 32 bit values; this function makes sure the result is
+ * non-zero.
+ */
+static png_uint_32
+random_32(void)
+{
+
+   for(;;)
+   {
+      png_byte mark[4];
+      png_uint_32 result;
+
+      store_pool_mark(mark);
+      result = png_get_uint_32(mark);
+
+      if (result != 0)
+         return result;
+   }
+}
+
+static void
+store_pool_init(png_store *ps, store_pool *pool)
+{
+   memset(pool, 0, sizeof *pool);
+
+   pool->store = ps;
+   pool->list = NULL;
+   pool->max = pool->current = pool->limit = pool->total = 0;
+   pool->max_max = pool->max_limit = pool->max_total = 0;
+   store_pool_mark(pool->mark);
+}
+
+static void
+store_init(png_store* ps)
+{
+   memset(ps, 0, sizeof *ps);
+   init_exception_context(&ps->exception_context);
+   store_pool_init(ps, &ps->read_memory_pool);
+   store_pool_init(ps, &ps->write_memory_pool);
+   ps->verbose = 0;
+   ps->treat_warnings_as_errors = 0;
+   ps->expect_error = 0;
+   ps->expect_warning = 0;
+   ps->saw_warning = 0;
+   ps->speed = 0;
+   ps->progressive = 0;
+   ps->validated = 0;
+   ps->nerrors = ps->nwarnings = 0;
+   ps->pread = NULL;
+   ps->piread = NULL;
+   ps->saved = ps->current = NULL;
+   ps->next = NULL;
+   ps->readpos = 0;
+   ps->image = NULL;
+   ps->cb_image = 0;
+   ps->cb_row = 0;
+   ps->image_h = 0;
+   ps->pwrite = NULL;
+   ps->piwrite = NULL;
+   ps->writepos = 0;
+   ps->new.prev = NULL;
+   ps->palette = NULL;
+   ps->npalette = 0;
+}
+
+static void
+store_freebuffer(png_store_buffer* psb)
+{
+   if (psb->prev)
+   {
+      store_freebuffer(psb->prev);
+      free(psb->prev);
+      psb->prev = NULL;
+   }
+}
+
+static void
+store_freenew(png_store *ps)
+{
+   store_freebuffer(&ps->new);
+   ps->writepos = 0;
+   if (ps->palette != NULL)
+   {
+      free(ps->palette);
+      ps->palette = NULL;
+      ps->npalette = 0;
+   }
+}
+
+static void
+store_storenew(png_store *ps)
+{
+   png_store_buffer *pb;
+
+   if (ps->writepos != STORE_BUFFER_SIZE)
+      png_error(ps->pwrite, "invalid store call");
+
+   pb = voidcast(png_store_buffer*, malloc(sizeof *pb));
+
+   if (pb == NULL)
+      png_error(ps->pwrite, "store new: OOM");
+
+   *pb = ps->new;
+   ps->new.prev = pb;
+   ps->writepos = 0;
+}
+
+static void
+store_freefile(png_store_file **ppf)
+{
+   if (*ppf != NULL)
+   {
+      store_freefile(&(*ppf)->next);
+
+      store_freebuffer(&(*ppf)->data);
+      (*ppf)->datacount = 0;
+      if ((*ppf)->palette != NULL)
+      {
+         free((*ppf)->palette);
+         (*ppf)->palette = NULL;
+         (*ppf)->npalette = 0;
+      }
+      free(*ppf);
+      *ppf = NULL;
+   }
+}
+
+/* Main interface to file storeage, after writing a new PNG file (see the API
+ * below) call store_storefile to store the result with the given name and id.
+ */
+static void
+store_storefile(png_store *ps, png_uint_32 id)
+{
+   png_store_file *pf = voidcast(png_store_file*, malloc(sizeof *pf));
+   if (pf == NULL)
+      png_error(ps->pwrite, "storefile: OOM");
+   safecat(pf->name, sizeof pf->name, 0, ps->wname);
+   pf->id = id;
+   pf->data = ps->new;
+   pf->datacount = ps->writepos;
+   ps->new.prev = NULL;
+   ps->writepos = 0;
+   pf->palette = ps->palette;
+   pf->npalette = ps->npalette;
+   ps->palette = 0;
+   ps->npalette = 0;
+
+   /* And save it. */
+   pf->next = ps->saved;
+   ps->saved = pf;
+}
+
+/* Generate an error message (in the given buffer) */
+static size_t
+store_message(png_store *ps, png_structp pp, char *buffer, size_t bufsize,
+   size_t pos, PNG_CONST char *msg)
+{
+   if (pp != NULL && pp == ps->pread)
+   {
+      /* Reading a file */
+      pos = safecat(buffer, bufsize, pos, "read: ");
+
+      if (ps->current != NULL)
+      {
+         pos = safecat(buffer, bufsize, pos, ps->current->name);
+         pos = safecat(buffer, bufsize, pos, sep);
+      }
+   }
+
+   else if (pp != NULL && pp == ps->pwrite)
+   {
+      /* Writing a file */
+      pos = safecat(buffer, bufsize, pos, "write: ");
+      pos = safecat(buffer, bufsize, pos, ps->wname);
+      pos = safecat(buffer, bufsize, pos, sep);
+   }
+
+   else
+   {
+      /* Neither reading nor writing (or a memory error in struct delete) */
+      pos = safecat(buffer, bufsize, pos, "pngvalid: ");
+   }
+
+   if (ps->test[0] != 0)
+   {
+      pos = safecat(buffer, bufsize, pos, ps->test);
+      pos = safecat(buffer, bufsize, pos, sep);
+   }
+   pos = safecat(buffer, bufsize, pos, msg);
+   return pos;
+}
+
+/* Verbose output to the error stream: */
+static void
+store_verbose(png_store *ps, png_structp pp, png_const_charp prefix,
+   png_const_charp message)
+{
+   char buffer[512];
+
+   if (prefix)
+      fputs(prefix, stderr);
+
+   (void)store_message(ps, pp, buffer, sizeof buffer, 0, message);
+   fputs(buffer, stderr);
+   fputc('\n', stderr);
+}
+
+/* Log an error or warning - the relevant count is always incremented. */
+static void
+store_log(png_store* ps, png_structp pp, png_const_charp message, int is_error)
+{
+   /* The warning is copied to the error buffer if there are no errors and it is
+    * the first warning.  The error is copied to the error buffer if it is the
+    * first error (overwriting any prior warnings).
+    */
+   if (is_error ? (ps->nerrors)++ == 0 :
+       (ps->nwarnings)++ == 0 && ps->nerrors == 0)
+      store_message(ps, pp, ps->error, sizeof ps->error, 0, message);
+
+   if (ps->verbose)
+      store_verbose(ps, pp, is_error ? "error: " : "warning: ", message);
+}
+
+/* Internal error function, called with a png_store but no libpng stuff. */
+static void
+internal_error(png_store *ps, png_const_charp message)
+{
+   store_log(ps, NULL, message, 1 /* error */);
+
+   /* And finally throw an exception. */
+   {
+      struct exception_context *the_exception_context = &ps->exception_context;
+      Throw ps;
+   }
+}
+
+/* Functions to use as PNG callbacks. */
+static void
+store_error(png_structp pp, png_const_charp message) /* PNG_NORETURN */
+{
+   png_store *ps = voidcast(png_store*, png_get_error_ptr(pp));
+
+   if (!ps->expect_error)
+      store_log(ps, pp, message, 1 /* error */);
+
+   /* And finally throw an exception. */
+   {
+      struct exception_context *the_exception_context = &ps->exception_context;
+      Throw ps;
+   }
+}
+
+static void
+store_warning(png_structp pp, png_const_charp message)
+{
+   png_store *ps = voidcast(png_store*, png_get_error_ptr(pp));
+
+   if (!ps->expect_warning)
+      store_log(ps, pp, message, 0 /* warning */);
+   else
+      ps->saw_warning = 1;
+}
+
+/* These somewhat odd functions are used when reading an image to ensure that
+ * the buffer is big enough, the png_structp is for errors.
+ */
+/* Return a single row from the correct image. */
+static png_bytep
+store_image_row(PNG_CONST png_store* ps, png_structp pp, int nImage,
+   png_uint_32 y)
+{
+   png_size_t coffset = (nImage * ps->image_h + y) * (ps->cb_row + 5) + 2;
+
+   if (ps->image == NULL)
+      png_error(pp, "no allocated image");
+
+   if (coffset + ps->cb_row + 3 > ps->cb_image)
+      png_error(pp, "image too small");
+
+   return ps->image + coffset;
+}
+
+static void
+store_image_free(png_store *ps, png_structp pp)
+{
+   if (ps->image != NULL)
+   {
+      png_bytep image = ps->image;
+
+      if (image[-1] != 0xed || image[ps->cb_image] != 0xfe)
+      {
+         if (pp != NULL)
+            png_error(pp, "png_store image overwrite (1)");
+         else
+            store_log(ps, NULL, "png_store image overwrite (2)", 1);
+      }
+
+      ps->image = NULL;
+      ps->cb_image = 0;
+      --image;
+      free(image);
+   }
+}
+
+static void
+store_ensure_image(png_store *ps, png_structp pp, int nImages, png_size_t cbRow,
+   png_uint_32 cRows)
+{
+   png_size_t cb = nImages * cRows * (cbRow + 5);
+
+   if (ps->cb_image < cb)
+   {
+      png_bytep image;
+
+      store_image_free(ps, pp);
+
+      /* The buffer is deliberately mis-aligned. */
+      image = voidcast(png_bytep, malloc(cb+2));
+      if (image == NULL)
+      {
+         /* Called from the startup - ignore the error for the moment. */
+         if (pp == NULL)
+            return;
+
+         png_error(pp, "OOM allocating image buffer");
+      }
+
+      /* These magic tags are used to detect overwrites above. */
+      ++image;
+      image[-1] = 0xed;
+      image[cb] = 0xfe;
+
+      ps->image = image;
+      ps->cb_image = cb;
+   }
+
+   /* We have an adequate sized image; lay out the rows.  There are 2 bytes at
+    * the start and three at the end of each (this ensures that the row
+    * alignment starts out odd - 2+1 and changes for larger images on each row.)
+    */
+   ps->cb_row = cbRow;
+   ps->image_h = cRows;
+
+   /* For error checking, the whole buffer is set to 10110010 (0xb2 - 178).
+    * This deliberately doesn't match the bits in the size test image which are
+    * outside the image; these are set to 0xff (all 1).  To make the row
+    * comparison work in the 'size' test case the size rows are pre-initialized
+    * to the same value prior to calling 'standard_row'.
+    */
+   memset(ps->image, 178, cb);
+
+   /* Then put in the marks. */
+   while (--nImages >= 0)
+   {
+      png_uint_32 y;
+
+      for (y=0; y<cRows; ++y)
+      {
+         png_bytep row = store_image_row(ps, pp, nImages, y);
+
+         /* The markers: */
+         row[-2] = 190;
+         row[-1] = 239;
+         row[cbRow] = 222;
+         row[cbRow+1] = 173;
+         row[cbRow+2] = 17;
+      }
+   }
+}
+
+static void
+store_image_check(PNG_CONST png_store* ps, png_structp pp, int iImage)
+{
+   png_const_bytep image = ps->image;
+
+   if (image[-1] != 0xed || image[ps->cb_image] != 0xfe)
+      png_error(pp, "image overwrite");
+   else
+   {
+      png_size_t cbRow = ps->cb_row;
+      png_uint_32 rows = ps->image_h;
+
+      image += iImage * (cbRow+5) * ps->image_h;
+
+      image += 2; /* skip image first row markers */
+
+      while (rows-- > 0)
+      {
+         if (image[-2] != 190 || image[-1] != 239)
+            png_error(pp, "row start overwritten");
+
+         if (image[cbRow] != 222 || image[cbRow+1] != 173 ||
+            image[cbRow+2] != 17)
+            png_error(pp, "row end overwritten");
+
+         image += cbRow+5;
+      }
+   }
+}
+
+static void
+store_write(png_structp pp, png_bytep pb, png_size_t st)
+{
+   png_store *ps = voidcast(png_store*, png_get_io_ptr(pp));
+
+   if (ps->pwrite != pp)
+      png_error(pp, "store state damaged");
+
+   while (st > 0)
+   {
+      size_t cb;
+
+      if (ps->writepos >= STORE_BUFFER_SIZE)
+         store_storenew(ps);
+
+      cb = st;
+
+      if (cb > STORE_BUFFER_SIZE - ps->writepos)
+         cb = STORE_BUFFER_SIZE - ps->writepos;
+
+      memcpy(ps->new.buffer + ps->writepos, pb, cb);
+      pb += cb;
+      st -= cb;
+      ps->writepos += cb;
+   }
+}
+
+static void
+store_flush(png_structp pp)
+{
+   UNUSED(pp) /*DOES NOTHING*/
+}
+
+static size_t
+store_read_buffer_size(png_store *ps)
+{
+   /* Return the bytes available for read in the current buffer. */
+   if (ps->next != &ps->current->data)
+      return STORE_BUFFER_SIZE;
+
+   return ps->current->datacount;
+}
+
+#ifdef PNG_READ_TRANSFORMS_SUPPORTED
+/* Return total bytes available for read. */
+static size_t
+store_read_buffer_avail(png_store *ps)
+{
+   if (ps->current != NULL && ps->next != NULL)
+   {
+      png_store_buffer *next = &ps->current->data;
+      size_t cbAvail = ps->current->datacount;
+
+      while (next != ps->next && next != NULL)
+      {
+         next = next->prev;
+         cbAvail += STORE_BUFFER_SIZE;
+      }
+
+      if (next != ps->next)
+         png_error(ps->pread, "buffer read error");
+
+      if (cbAvail > ps->readpos)
+         return cbAvail - ps->readpos;
+   }
+
+   return 0;
+}
+#endif
+
+static int
+store_read_buffer_next(png_store *ps)
+{
+   png_store_buffer *pbOld = ps->next;
+   png_store_buffer *pbNew = &ps->current->data;
+   if (pbOld != pbNew)
+   {
+      while (pbNew != NULL && pbNew->prev != pbOld)
+         pbNew = pbNew->prev;
+
+      if (pbNew != NULL)
+      {
+         ps->next = pbNew;
+         ps->readpos = 0;
+         return 1;
+      }
+
+      png_error(ps->pread, "buffer lost");
+   }
+
+   return 0; /* EOF or error */
+}
+
+/* Need separate implementation and callback to allow use of the same code
+ * during progressive read, where the io_ptr is set internally by libpng.
+ */
+static void
+store_read_imp(png_store *ps, png_bytep pb, png_size_t st)
+{
+   if (ps->current == NULL || ps->next == NULL)
+      png_error(ps->pread, "store state damaged");
+
+   while (st > 0)
+   {
+      size_t cbAvail = store_read_buffer_size(ps) - ps->readpos;
+
+      if (cbAvail > 0)
+      {
+         if (cbAvail > st) cbAvail = st;
+         memcpy(pb, ps->next->buffer + ps->readpos, cbAvail);
+         st -= cbAvail;
+         pb += cbAvail;
+         ps->readpos += cbAvail;
+      }
+
+      else if (!store_read_buffer_next(ps))
+         png_error(ps->pread, "read beyond end of file");
+   }
+}
+
+static void
+store_read(png_structp pp, png_bytep pb, png_size_t st)
+{
+   png_store *ps = voidcast(png_store*, png_get_io_ptr(pp));
+
+   if (ps == NULL || ps->pread != pp)
+      png_error(pp, "bad store read call");
+
+   store_read_imp(ps, pb, st);
+}
+
+static void
+store_progressive_read(png_store *ps, png_structp pp, png_infop pi)
+{
+   /* Notice that a call to store_read will cause this function to fail because
+    * readpos will be set.
+    */
+   if (ps->pread != pp || ps->current == NULL || ps->next == NULL)
+      png_error(pp, "store state damaged (progressive)");
+
+   do
+   {
+      if (ps->readpos != 0)
+         png_error(pp, "store_read called during progressive read");
+
+      png_process_data(pp, pi, ps->next->buffer, store_read_buffer_size(ps));
+   }
+   while (store_read_buffer_next(ps));
+}
+
+/* The caller must fill this in: */
+static store_palette_entry *
+store_write_palette(png_store *ps, int npalette)
+{
+   if (ps->pwrite == NULL)
+      store_log(ps, NULL, "attempt to write palette without write stream", 1);
+
+   if (ps->palette != NULL)
+      png_error(ps->pwrite, "multiple store_write_palette calls");
+
+   /* This function can only return NULL if called with '0'! */
+   if (npalette > 0)
+   {
+      ps->palette = voidcast(store_palette_entry*, malloc(npalette *
+         sizeof *ps->palette));
+
+      if (ps->palette == NULL)
+         png_error(ps->pwrite, "store new palette: OOM");
+
+      ps->npalette = npalette;
+   }
+
+   return ps->palette;
+}
+
+static store_palette_entry *
+store_current_palette(png_store *ps, int *npalette)
+{
+   /* This is an internal error (the call has been made outside a read
+    * operation.)
+    */
+   if (ps->current == NULL)
+      store_log(ps, ps->pread, "no current stream for palette", 1);
+
+   /* The result may be null if there is no palette. */
+   *npalette = ps->current->npalette;
+   return ps->current->palette;
+}
+
+/***************************** MEMORY MANAGEMENT*** ***************************/
+/* A store_memory is simply the header for an allocated block of memory.  The
+ * pointer returned to libpng is just after the end of the header block, the
+ * allocated memory is followed by a second copy of the 'mark'.
+ */
+typedef struct store_memory
+{
+   store_pool          *pool;    /* Originating pool */
+   struct store_memory *next;    /* Singly linked list */
+   png_alloc_size_t     size;    /* Size of memory allocated */
+   png_byte             mark[4]; /* ID marker */
+} store_memory;
+
+/* Handle a fatal error in memory allocation.  This calls png_error if the
+ * libpng struct is non-NULL, else it outputs a message and returns.  This means
+ * that a memory problem while libpng is running will abort (png_error) the
+ * handling of particular file while one in cleanup (after the destroy of the
+ * struct has returned) will simply keep going and free (or attempt to free)
+ * all the memory.
+ */
+static void
+store_pool_error(png_store *ps, png_structp pp, PNG_CONST char *msg)
+{
+   if (pp != NULL)
+      png_error(pp, msg);
+
+   /* Else we have to do it ourselves.  png_error eventually calls store_log,
+    * above.  store_log accepts a NULL png_structp - it just changes what gets
+    * output by store_message.
+    */
+   store_log(ps, pp, msg, 1 /* error */);
+}
+
+static void
+store_memory_free(png_structp pp, store_pool *pool, store_memory *memory)
+{
+   /* Note that pp may be NULL (see store_pool_delete below), the caller has
+    * found 'memory' in pool->list *and* unlinked this entry, so this is a valid
+    * pointer (for sure), but the contents may have been trashed.
+    */
+   if (memory->pool != pool)
+      store_pool_error(pool->store, pp, "memory corrupted (pool)");
+
+   else if (memcmp(memory->mark, pool->mark, sizeof memory->mark) != 0)
+      store_pool_error(pool->store, pp, "memory corrupted (start)");
+
+   /* It should be safe to read the size field now. */
+   else
+   {
+      png_alloc_size_t cb = memory->size;
+
+      if (cb > pool->max)
+         store_pool_error(pool->store, pp, "memory corrupted (size)");
+
+      else if (memcmp((png_bytep)(memory+1)+cb, pool->mark, sizeof pool->mark)
+         != 0)
+         store_pool_error(pool->store, pp, "memory corrupted (end)");
+
+      /* Finally give the library a chance to find problems too: */
+      else
+         {
+         pool->current -= cb;
+         free(memory);
+         }
+   }
+}
+
+static void
+store_pool_delete(png_store *ps, store_pool *pool)
+{
+   if (pool->list != NULL)
+   {
+      fprintf(stderr, "%s: %s %s: memory lost (list follows):\n", ps->test,
+         pool == &ps->read_memory_pool ? "read" : "write",
+         pool == &ps->read_memory_pool ? (ps->current != NULL ?
+            ps->current->name : "unknown file") : ps->wname);
+      ++ps->nerrors;
+
+      do
+      {
+         store_memory *next = pool->list;
+         pool->list = next->next;
+         next->next = NULL;
+
+         fprintf(stderr, "\t%lu bytes @ %p\n",
+             (unsigned long)next->size, (PNG_CONST void*)(next+1));
+         /* The NULL means this will always return, even if the memory is
+          * corrupted.
+          */
+         store_memory_free(NULL, pool, next);
+      }
+      while (pool->list != NULL);
+   }
+
+   /* And reset the other fields too for the next time. */
+   if (pool->max > pool->max_max) pool->max_max = pool->max;
+   pool->max = 0;
+   if (pool->current != 0) /* unexpected internal error */
+      fprintf(stderr, "%s: %s %s: memory counter mismatch (internal error)\n",
+         ps->test, pool == &ps->read_memory_pool ? "read" : "write",
+         pool == &ps->read_memory_pool ? (ps->current != NULL ?
+            ps->current->name : "unknown file") : ps->wname);
+   pool->current = 0;
+
+   if (pool->limit > pool->max_limit)
+      pool->max_limit = pool->limit;
+
+   pool->limit = 0;
+
+   if (pool->total > pool->max_total)
+      pool->max_total = pool->total;
+
+   pool->total = 0;
+
+   /* Get a new mark too. */
+   store_pool_mark(pool->mark);
+}
+
+/* The memory callbacks: */
+static png_voidp
+store_malloc(png_structp pp, png_alloc_size_t cb)
+{
+   store_pool *pool = voidcast(store_pool*, png_get_mem_ptr(pp));
+   store_memory *new = voidcast(store_memory*, malloc(cb + (sizeof *new) +
+      (sizeof pool->mark)));
+
+   if (new != NULL)
+   {
+      if (cb > pool->max)
+         pool->max = cb;
+
+      pool->current += cb;
+
+      if (pool->current > pool->limit)
+         pool->limit = pool->current;
+
+      pool->total += cb;
+
+      new->size = cb;
+      memcpy(new->mark, pool->mark, sizeof new->mark);
+      memcpy((png_byte*)(new+1) + cb, pool->mark, sizeof pool->mark);
+      new->pool = pool;
+      new->next = pool->list;
+      pool->list = new;
+      ++new;
+   }
+
+   else
+   {
+      /* NOTE: the PNG user malloc function cannot use the png_ptr it is passed
+       * other than to retrieve the allocation pointer!  libpng calls the
+       * store_malloc callback in two basic cases:
+       *
+       * 1) From png_malloc; png_malloc will do a png_error itself if NULL is
+       *    returned.
+       * 2) From png_struct or png_info structure creation; png_malloc is
+       *    to return so cleanup can be performed.
+       *
+       * To handle this store_malloc can log a message, but can't do anything
+       * else.
+       */
+      store_log(pool->store, pp, "out of memory", 1 /* is_error */);
+   }
+
+   return new;
+}
+
+static void
+store_free(png_structp pp, png_voidp memory)
+{
+   store_pool *pool = voidcast(store_pool*, png_get_mem_ptr(pp));
+   store_memory *this = voidcast(store_memory*, memory), **test;
+
+   /* Because libpng calls store_free with a dummy png_struct when deleting
+    * png_struct or png_info via png_destroy_struct_2 it is necessary to check
+    * the passed in png_structp to ensure it is valid, and not pass it to
+    * png_error if it is not.
+    */
+   if (pp != pool->store->pread && pp != pool->store->pwrite)
+      pp = NULL;
+
+   /* First check that this 'memory' really is valid memory - it must be in the
+    * pool list.  If it is, use the shared memory_free function to free it.
+    */
+   --this;
+   for (test = &pool->list; *test != this; test = &(*test)->next)
+   {
+      if (*test == NULL)
+      {
+         store_pool_error(pool->store, pp, "bad pointer to free");
+         return;
+      }
+   }
+
+   /* Unlink this entry, *test == this. */
+   *test = this->next;
+   this->next = NULL;
+   store_memory_free(pp, pool, this);
+}
+
+/* Setup functions. */
+/* Cleanup when aborting a write or after storing the new file. */
+static void
+store_write_reset(png_store *ps)
+{
+   if (ps->pwrite != NULL)
+   {
+      anon_context(ps);
+
+      Try
+         png_destroy_write_struct(&ps->pwrite, &ps->piwrite);
+
+      Catch_anonymous
+      {
+         /* memory corruption: continue. */
+      }
+
+      ps->pwrite = NULL;
+      ps->piwrite = NULL;
+   }
+
+   /* And make sure that all the memory has been freed - this will output
+    * spurious errors in the case of memory corruption above, but this is safe.
+    */
+   store_pool_delete(ps, &ps->write_memory_pool);
+
+   store_freenew(ps);
+}
+
+/* The following is the main write function, it returns a png_struct and,
+ * optionally, a png_info suitable for writiing a new PNG file.  Use
+ * store_storefile above to record this file after it has been written.  The
+ * returned libpng structures as destroyed by store_write_reset above.
+ */
+static png_structp
+set_store_for_write(png_store *ps, png_infopp ppi,
+   PNG_CONST char * volatile name)
+{
+   anon_context(ps);
+
+   Try
+   {
+      if (ps->pwrite != NULL)
+         png_error(ps->pwrite, "write store already in use");
+
+      store_write_reset(ps);
+      safecat(ps->wname, sizeof ps->wname, 0, name);
+
+      /* Don't do the slow memory checks if doing a speed test. */
+      if (ps->speed)
+         ps->pwrite = png_create_write_struct(PNG_LIBPNG_VER_STRING,
+            ps, store_error, store_warning);
+
+      else
+         ps->pwrite = png_create_write_struct_2(PNG_LIBPNG_VER_STRING,
+            ps, store_error, store_warning, &ps->write_memory_pool,
+            store_malloc, store_free);
+
+      png_set_write_fn(ps->pwrite, ps, store_write, store_flush);
+
+      if (ppi != NULL)
+         *ppi = ps->piwrite = png_create_info_struct(ps->pwrite);
+   }
+
+   Catch_anonymous
+      return NULL;
+
+   return ps->pwrite;
+}
+
+/* Cleanup when finished reading (either due to error or in the success case).
+ */
+static void
+store_read_reset(png_store *ps)
+{
+   if (ps->pread != NULL)
+   {
+      anon_context(ps);
+
+      Try
+         png_destroy_read_struct(&ps->pread, &ps->piread, NULL);
+
+      Catch_anonymous
+      {
+         /* error already output: continue */
+      }
+
+      ps->pread = NULL;
+      ps->piread = NULL;
+   }
+
+   /* Always do this to be safe. */
+   store_pool_delete(ps, &ps->read_memory_pool);
+
+   ps->current = NULL;
+   ps->next = NULL;
+   ps->readpos = 0;
+   ps->validated = 0;
+}
+
+static void
+store_read_set(png_store *ps, png_uint_32 id)
+{
+   png_store_file *pf = ps->saved;
+
+   while (pf != NULL)
+   {
+      if (pf->id == id)
+      {
+         ps->current = pf;
+         ps->next = NULL;
+         store_read_buffer_next(ps);
+         return;
+      }
+
+      pf = pf->next;
+   }
+
+      {
+      size_t pos;
+      char msg[FILE_NAME_SIZE+64];
+
+      pos = standard_name_from_id(msg, sizeof msg, 0, id);
+      pos = safecat(msg, sizeof msg, pos, ": file not found");
+      png_error(ps->pread, msg);
+      }
+}
+
+/* The main interface for reading a saved file - pass the id number of the file
+ * to retrieve.  Ids must be unique or the earlier file will be hidden.  The API
+ * returns a png_struct and, optionally, a png_info.  Both of these will be
+ * destroyed by store_read_reset above.
+ */
+static png_structp
+set_store_for_read(png_store *ps, png_infopp ppi, png_uint_32 id,
+   PNG_CONST char *name)
+{
+   /* Set the name for png_error */
+   safecat(ps->test, sizeof ps->test, 0, name);
+
+   if (ps->pread != NULL)
+      png_error(ps->pread, "read store already in use");
+
+   store_read_reset(ps);
+
+   /* Both the create APIs can return NULL if used in their default mode
+    * (because there is no other way of handling an error because the jmp_buf
+    * by default is stored in png_struct and that has not been allocated!)
+    * However, given that store_error works correctly in these circumstances
+    * we don't ever expect NULL in this program.
+    */
+   if (ps->speed)
+      ps->pread = png_create_read_struct(PNG_LIBPNG_VER_STRING, ps,
+          store_error, store_warning);
+
+   else
+      ps->pread = png_create_read_struct_2(PNG_LIBPNG_VER_STRING, ps,
+          store_error, store_warning, &ps->read_memory_pool, store_malloc,
+          store_free);
+
+   if (ps->pread == NULL)
+   {
+      struct exception_context *the_exception_context = &ps->exception_context;
+
+      store_log(ps, NULL, "png_create_read_struct returned NULL (unexpected)",
+         1 /*error*/);
+
+      Throw ps;
+   }
+
+   store_read_set(ps, id);
+
+   if (ppi != NULL)
+      *ppi = ps->piread = png_create_info_struct(ps->pread);
+
+   return ps->pread;
+}
+
+/* The overall cleanup of a store simply calls the above then removes all the
+ * saved files.  This does not delete the store itself.
+ */
+static void
+store_delete(png_store *ps)
+{
+   store_write_reset(ps);
+   store_read_reset(ps);
+   store_freefile(&ps->saved);
+   store_image_free(ps, NULL);
+}
+
+/*********************** PNG FILE MODIFICATION ON READ ************************/
+/* Files may be modified on read.  The following structure contains a complete
+ * png_store together with extra members to handle modification and a special
+ * read callback for libpng.  To use this the 'modifications' field must be set
+ * to a list of png_modification structures that actually perform the
+ * modification, otherwise a png_modifier is functionally equivalent to a
+ * png_store.  There is a special read function, set_modifier_for_read, which
+ * replaces set_store_for_read.
+ */
+typedef enum modifier_state
+{
+   modifier_start,                        /* Initial value */
+   modifier_signature,                    /* Have a signature */
+   modifier_IHDR                          /* Have an IHDR */
+} modifier_state;
+
+typedef struct CIE_color
+{
+   /* A single CIE tristimulus value, representing the unique response of a
+    * standard observer to a variety of light spectra.  The observer recognizes
+    * all spectra that produce this response as the same color, therefore this
+    * is effectively a description of a color.
+    */
+   double X, Y, Z;
+} CIE_color;
+
+static double
+chromaticity_x(CIE_color c)
+{
+   return c.X / (c.X + c.Y + c.Z);
+}
+
+static double
+chromaticity_y(CIE_color c)
+{
+   return c.Y / (c.X + c.Y + c.Z);
+}
+
+typedef struct color_encoding
+{
+   /* A description of an (R,G,B) encoding of color (as defined above); this
+    * includes the actual colors of the (R,G,B) triples (1,0,0), (0,1,0) and
+    * (0,0,1) plus an encoding value that is used to encode the linear
+    * components R, G and B to give the actual values R^gamma, G^gamma and
+    * B^gamma that are stored.
+    */
+   double    gamma;            /* Encoding (file) gamma of space */
+   CIE_color red, green, blue; /* End points */
+} color_encoding;
+
+static CIE_color
+white_point(PNG_CONST color_encoding *encoding)
+{
+   CIE_color white;
+   
+   white.X = encoding->red.X + encoding->green.X + encoding->blue.X;
+   white.Y = encoding->red.Y + encoding->green.Y + encoding->blue.Y;
+   white.Z = encoding->red.Z + encoding->green.Z + encoding->blue.Z;
+
+   return white;
+}
+
+static void
+normalize_color_encoding(color_encoding *encoding)
+{
+   PNG_CONST double whiteY = encoding->red.Y + encoding->green.Y +
+      encoding->blue.Y;
+
+   if (whiteY != 1)
+   {
+      encoding->red.X /= whiteY;
+      encoding->red.Y /= whiteY;
+      encoding->red.Z /= whiteY;
+      encoding->green.X /= whiteY;
+      encoding->green.Y /= whiteY;
+      encoding->green.Z /= whiteY;
+      encoding->blue.X /= whiteY;
+      encoding->blue.Y /= whiteY;
+      encoding->blue.Z /= whiteY;
+   }
+}
+
+static size_t
+safecat_color_encoding(char *buffer, size_t bufsize, size_t pos,
+   PNG_CONST color_encoding *e, double encoding_gamma)
+{
+   if (e != 0)
+   {
+      if (encoding_gamma != 0)
+         pos = safecat(buffer, bufsize, pos, "(");
+      pos = safecat(buffer, bufsize, pos, "R(");
+      pos = safecatd(buffer, bufsize, pos, e->red.X, 4);
+      pos = safecat(buffer, bufsize, pos, ",");
+      pos = safecatd(buffer, bufsize, pos, e->red.Y, 4);
+      pos = safecat(buffer, bufsize, pos, ",");
+      pos = safecatd(buffer, bufsize, pos, e->red.Z, 4);
+      pos = safecat(buffer, bufsize, pos, "),G(");
+      pos = safecatd(buffer, bufsize, pos, e->green.X, 4);
+      pos = safecat(buffer, bufsize, pos, ",");
+      pos = safecatd(buffer, bufsize, pos, e->green.Y, 4);
+      pos = safecat(buffer, bufsize, pos, ",");
+      pos = safecatd(buffer, bufsize, pos, e->green.Z, 4);
+      pos = safecat(buffer, bufsize, pos, "),B(");
+      pos = safecatd(buffer, bufsize, pos, e->blue.X, 4);
+      pos = safecat(buffer, bufsize, pos, ",");
+      pos = safecatd(buffer, bufsize, pos, e->blue.Y, 4);
+      pos = safecat(buffer, bufsize, pos, ",");
+      pos = safecatd(buffer, bufsize, pos, e->blue.Z, 4);
+      pos = safecat(buffer, bufsize, pos, ")");
+      if (encoding_gamma != 0)
+         pos = safecat(buffer, bufsize, pos, ")");
+   }
+
+   if (encoding_gamma != 0)
+   {
+      pos = safecat(buffer, bufsize, pos, "^");
+      pos = safecatd(buffer, bufsize, pos, encoding_gamma, 5);
+   }
+
+   return pos;
+}
+
+typedef struct png_modifier
+{
+   png_store               this;             /* I am a png_store */
+   struct png_modification *modifications;   /* Changes to make */
+
+   modifier_state           state;           /* My state */
+
+   /* Information from IHDR: */
+   png_byte                 bit_depth;       /* From IHDR */
+   png_byte                 colour_type;     /* From IHDR */
+
+   /* While handling PLTE, IDAT and IEND these chunks may be pended to allow
+    * other chunks to be inserted.
+    */
+   png_uint_32              pending_len;
+   png_uint_32              pending_chunk;
+
+   /* Test values */
+   double                   *gammas;
+   unsigned int              ngammas;
+   unsigned int              ngamma_tests;     /* Number of gamma tests to run*/
+   double                    current_gamma;    /* 0 if not set */
+   PNG_CONST color_encoding *encodings;
+   unsigned int              nencodings;
+   PNG_CONST color_encoding *current_encoding; /* If an encoding has been set */
+   unsigned int              encoding_counter; /* For iteration */
+   int                       encoding_ignored; /* Something overwrote it */
+
+   /* Control variables used to iterate through possible encodings, the
+    * following must be set to 0 and tested by the function that uses the
+    * png_modifier because the modifier only sets it to 1 (true.)
+    */
+   unsigned int              repeat :1;   /* Repeat this transform test. */
+   unsigned int              test_uses_encoding :1;
+
+   /* Lowest sbit to test (libpng fails for sbit < 8) */
+   png_byte                 sbitlow;
+
+   /* Error control - these are the limits on errors accepted by the gamma tests
+    * below.
+    */
+   double                   maxout8;  /* Maximum output value error */
+   double                   maxabs8;  /* Absolute sample error 0..1 */
+   double                   maxcalc8; /* Absolute sample error 0..1 */
+   double                   maxpc8;   /* Percentage sample error 0..100% */
+   double                   maxout16; /* Maximum output value error */
+   double                   maxabs16; /* Absolute sample error 0..1 */
+   double                   maxcalc16;/* Absolute sample error 0..1 */
+   double                   maxpc16;  /* Percentage sample error 0..100% */
+
+   /* This is set by transforms that need to allow a higher limit, it is an
+    * internal check on pngvalid to ensure that the calculated error limits are
+    * not ridiculous; without this it is too easy to make a mistake in pngvalid
+    * that allows any value through.
+    */
+   double                   limit;    /* limit on error values, normally 4E-3 */
+
+   /* Log limits - values above this are logged, but not necessarily
+    * warned.
+    */
+   double                   log8;     /* Absolute error in 8 bits to log */
+   double                   log16;    /* Absolute error in 16 bits to log */
+
+   /* Logged 8 and 16 bit errors ('output' values): */
+   double                   error_gray_2;
+   double                   error_gray_4;
+   double                   error_gray_8;
+   double                   error_gray_16;
+   double                   error_color_8;
+   double                   error_color_16;
+   double                   error_indexed;
+
+   /* Flags: */
+   /* Whether to call png_read_update_info, not png_read_start_image, and how
+    * many times to call it.
+    */
+   int                      use_update_info;
+
+   /* Whether or not to interlace. */
+   int                      interlace_type :9; /* int, but must store '1' */
+
+   /* Run the standard tests? */
+   unsigned int             test_standard :1;
+
+   /* Run the odd-sized image and interlace read/write tests? */
+   unsigned int             test_size :1;
+
+   /* Run tests on reading with a combiniation of transforms, */
+   unsigned int             test_transform :1;
+
+   /* When to use the use_input_precision option: */
+   unsigned int             use_input_precision :1;
+   unsigned int             use_input_precision_sbit :1;
+   unsigned int             use_input_precision_16to8 :1;
+
+   /* If set assume that the calculation bit depth is set by the input
+    * precision, not the output precision.
+    */
+   unsigned int             calculations_use_input_precision :1;
+
+   /* If set assume that the calculations are done in 16 bits even if both input
+    * and output are 8 bit or less.
+    */
+   unsigned int             assume_16_bit_calculations :1;
+
+   /* Which gamma tests to run: */
+   unsigned int             test_gamma_threshold :1;
+   unsigned int             test_gamma_transform :1; /* main tests */
+   unsigned int             test_gamma_sbit :1;
+   unsigned int             test_gamma_scale16 :1;
+   unsigned int             test_gamma_background :1;
+   unsigned int             test_gamma_alpha_mode :1;
+   unsigned int             test_gamma_expand16 :1;
+   unsigned int             test_exhaustive :1;
+
+   unsigned int             log :1;   /* Log max error */
+
+   /* Buffer information, the buffer size limits the size of the chunks that can
+    * be modified - they must fit (including header and CRC) into the buffer!
+    */
+   size_t                   flush;           /* Count of bytes to flush */
+   size_t                   buffer_count;    /* Bytes in buffer */
+   size_t                   buffer_position; /* Position in buffer */
+   png_byte                 buffer[1024];
+} png_modifier;
+
+/* This returns true if the test should be stopped now because it has already
+ * failed and it is running silently.
+ */
+static int fail(png_modifier *pm)
+{
+   return !pm->log && !pm->this.verbose && (pm->this.nerrors > 0 ||
+       (pm->this.treat_warnings_as_errors && pm->this.nwarnings > 0));
+}
+
+static void
+modifier_init(png_modifier *pm)
+{
+   memset(pm, 0, sizeof *pm);
+   store_init(&pm->this);
+   pm->modifications = NULL;
+   pm->state = modifier_start;
+   pm->sbitlow = 1U;
+   pm->ngammas = 0;
+   pm->ngamma_tests = 0;
+   pm->gammas = 0;
+   pm->current_gamma = 0;
+   pm->encodings = 0;
+   pm->nencodings = 0;
+   pm->current_encoding = 0;
+   pm->encoding_counter = 0;
+   pm->encoding_ignored = 0;
+   pm->repeat = 0;
+   pm->test_uses_encoding = 0;
+   pm->maxout8 = pm->maxpc8 = pm->maxabs8 = pm->maxcalc8 = 0;
+   pm->maxout16 = pm->maxpc16 = pm->maxabs16 = pm->maxcalc16 = 0;
+   pm->limit = 4E-3;
+   pm->log8 = pm->log16 = 0; /* Means 'off' */
+   pm->error_gray_2 = pm->error_gray_4 = pm->error_gray_8 = 0;
+   pm->error_gray_16 = pm->error_color_8 = pm->error_color_16 = 0;
+   pm->error_indexed = 0;
+   pm->use_update_info = 0;
+   pm->interlace_type = PNG_INTERLACE_NONE;
+   pm->test_standard = 0;
+   pm->test_size = 0;
+   pm->test_transform = 0;
+   pm->use_input_precision = 0;
+   pm->use_input_precision_sbit = 0;
+   pm->use_input_precision_16to8 = 0;
+   pm->calculations_use_input_precision = 0;
+   pm->test_gamma_threshold = 0;
+   pm->test_gamma_transform = 0;
+   pm->test_gamma_sbit = 0;
+   pm->test_gamma_scale16 = 0;
+   pm->test_gamma_background = 0;
+   pm->test_gamma_alpha_mode = 0;
+   pm->test_gamma_expand16 = 0;
+   pm->test_exhaustive = 0;
+   pm->log = 0;
+
+   /* Rely on the memset for all the other fields - there are no pointers */
+}
+
+#ifdef PNG_READ_TRANSFORMS_SUPPORTED
+/* If pm->calculations_use_input_precision is set then operations will happen
+ * with only 8 bit precision unless both the input and output bit depth are 16.
+ *
+ * If pm->assume_16_bit_calculations is set then even 8 bit calculations use 16
+ * bit precision.  This only affects those of the following limits that pertain
+ * to a calculation - not a digitization operation - unless the following API is
+ * called directly.
+ */
+static double digitize(PNG_CONST png_modifier *pm, double value,
+   int sample_depth, int do_round)
+{
+   /* 'value' is in the range 0 to 1, the result is the same value rounded to a
+    * multiple of the digitization factor - 8 or 16 bits depending on both the
+    * sample depth and the 'assume' setting.  Digitization is normally by
+    * rounding and 'do_round' should be 1, if it is 0 the digitized value will
+    * be truncated.
+    */
+   PNG_CONST unsigned int digitization_factor =
+      (pm->assume_16_bit_calculations || sample_depth == 16) ? 65535 : 255;
+
+   /* Limiting the range is done as a convenience to the caller - it's easier to
+    * do it once here than every time at the call site.
+    */
+   if (value <= 0)
+      value = 0;
+   else if (value >= 1)
+      value = 1;
+
+   value *= digitization_factor;
+   if (do_round) value += .5;
+   return floor(value)/digitization_factor;
+}
+
+static double abserr(PNG_CONST png_modifier *pm, int in_depth, int out_depth)
+{
+   /* Absolute error permitted in linear values - affected by the bit depth of
+    * the calculations.
+    */
+   if (pm->assume_16_bit_calculations || (out_depth == 16 && (in_depth == 16 ||
+      !pm->calculations_use_input_precision)))
+      return pm->maxabs16;
+   else
+      return pm->maxabs8;
+}
+
+static double calcerr(PNG_CONST png_modifier *pm, int in_depth, int out_depth)
+{
+   /* Error in the linear composition arithmetic - only relevant when
+    * composition actually happens (0 < alpha < 1).
+    */
+   if (pm->assume_16_bit_calculations || (out_depth == 16 && (in_depth == 16 ||
+      !pm->calculations_use_input_precision)))
+      return pm->maxcalc16;
+   else
+      return pm->maxcalc8;
+}
+
+static double pcerr(PNG_CONST png_modifier *pm, int in_depth, int out_depth)
+{
+   /* Percentage error permitted in the linear values.  Note that the specified
+    * value is a percentage but this routine returns a simple number.
+    */
+   if (pm->assume_16_bit_calculations || (out_depth == 16 && (in_depth == 16 ||
+      !pm->calculations_use_input_precision)))
+      return pm->maxpc16 * .01;
+   else
+      return pm->maxpc8 * .01;
+}
+
+/* Output error - the error in the encoded value.  This is determined by the
+ * digitization of the output so can be +/-0.5 in the actual output value.  In
+ * the expand_16 case with the current code in libpng the expand happens after
+ * all the calculations are done in 8 bit arithmetic, so even though the output
+ * depth is 16 the output error is determined by the 8 bit calculation.
+ *
+ * This limit is not determined by the bit depth of internal calculations.
+ *
+ * The specified parameter does *not* include the base .5 digitization error but
+ * it is added here.
+ */
+static double outerr(PNG_CONST png_modifier *pm, int in_depth, int out_depth)
+{
+   /* There is a serious error in the 2 and 4 bit grayscale transform because
+    * the gamma table value (8 bits) is simply shifted, not rounded, so the
+    * error in 4 bit grayscale gamma is up to the value below.  This is a hack
+    * to allow pngvalid to succeed:
+    *
+    * TODO: fix this in libpng
+    */
+   if (out_depth == 2)
+      return .73182-.5;
+
+   if (out_depth == 4)
+      return .90644-.5;
+
+   if (out_depth == 16 && (in_depth == 16 ||
+      !pm->calculations_use_input_precision))
+      return pm->maxout16;
+
+   /* This is the case where the value was calculated at 8-bit precision then
+    * scaled to 16 bits.
+    */
+   else if (out_depth == 16)
+      return pm->maxout8 * 257;
+
+   else
+      return pm->maxout8;
+}
+
+/* This does the same thing as the above however it returns the value to log,
+ * rather than raising a warning.  This is useful for debugging to track down
+ * exactly what set of parameters cause high error values.
+ */
+static double outlog(PNG_CONST png_modifier *pm, int in_depth, int out_depth)
+{
+   /* The command line parameters are either 8 bit (0..255) or 16 bit (0..65535)
+    * and so must be adjusted for low bit depth grayscale:
+    */
+   if (out_depth <= 8)
+   {
+      if (pm->log8 == 0) /* switched off */
+         return 256;
+
+      if (out_depth < 8)
+         return pm->log8 / 255 * ((1<<out_depth)-1);
+
+      return pm->log8;
+   }
+
+   if (out_depth == 16 && (in_depth == 16 ||
+      !pm->calculations_use_input_precision))
+   {
+      if (pm->log16 == 0)
+         return 65536;
+
+      return pm->log16;
+   }
+
+   /* This is the case where the value was calculated at 8-bit precision then
+    * scaled to 16 bits.
+    */
+   if (pm->log8 == 0)
+      return 65536;
+
+   return pm->log8 * 257;
+}
+
+/* This complements the above by providing the appropriate quantization for the
+ * final value.  Normally this would just be quantization to an integral value,
+ * but in the 8 bit calculation case it's actually quantization to a multiple of
+ * 257!
+ */
+static int output_quantization_factor(PNG_CONST png_modifier *pm, int in_depth,
+   int out_depth)
+{
+   if (out_depth == 16 && in_depth != 16
+      && pm->calculations_use_input_precision)
+      return 257;
+   else
+      return 1;
+}
+
+/* One modification structure must be provided for each chunk to be modified (in
+ * fact more than one can be provided if multiple separate changes are desired
+ * for a single chunk.)  Modifications include adding a new chunk when a
+ * suitable chunk does not exist.
+ *
+ * The caller of modify_fn will reset the CRC of the chunk and record 'modified'
+ * or 'added' as appropriate if the modify_fn returns 1 (true).  If the
+ * modify_fn is NULL the chunk is simply removed.
+ */
+typedef struct png_modification
+{
+   struct png_modification *next;
+   png_uint_32              chunk;
+
+   /* If the following is NULL all matching chunks will be removed: */
+   int                    (*modify_fn)(struct png_modifier *pm,
+                               struct png_modification *me, int add);
+
+   /* If the following is set to PLTE, IDAT or IEND and the chunk has not been
+    * found and modified (and there is a modify_fn) the modify_fn will be called
+    * to add the chunk before the relevant chunk.
+    */
+   png_uint_32              add;
+   unsigned int             modified :1;     /* Chunk was modified */
+   unsigned int             added    :1;     /* Chunk was added */
+   unsigned int             removed  :1;     /* Chunk was removed */
+} png_modification;
+
+static void
+modification_reset(png_modification *pmm)
+{
+   if (pmm != NULL)
+   {
+      pmm->modified = 0;
+      pmm->added = 0;
+      pmm->removed = 0;
+      modification_reset(pmm->next);
+   }
+}
+
+static void
+modification_init(png_modification *pmm)
+{
+   memset(pmm, 0, sizeof *pmm);
+   pmm->next = NULL;
+   pmm->chunk = 0;
+   pmm->modify_fn = NULL;
+   pmm->add = 0;
+   modification_reset(pmm);
+}
+
+static void
+modifier_current_encoding(PNG_CONST png_modifier *pm, color_encoding *ce)
+{
+   if (pm->current_encoding != 0)
+      *ce = *pm->current_encoding;
+
+   else
+      memset(ce, 0, sizeof *ce);
+
+   ce->gamma = pm->current_gamma;
+}
+
+static size_t
+safecat_current_encoding(char *buffer, size_t bufsize, size_t pos,
+   PNG_CONST png_modifier *pm)
+{
+   pos = safecat_color_encoding(buffer, bufsize, pos, pm->current_encoding,
+      pm->current_gamma);
+
+   if (pm->encoding_ignored)
+      pos = safecat(buffer, bufsize, pos, "[overridden]");
+
+   return pos;
+}
+
+/* Iterate through the usefully testable color encodings.  An encoding is one
+ * of:
+ *
+ * 1) Nothing (no color space, no gamma).
+ * 2) Just a gamma value from the gamma array (including 1.0)
+ * 3) A color space from the encodings array with the corresponding gamma.
+ * 4) The same, but with gamma 1.0 (only really useful with 16 bit calculations)
+ *
+ * The iterator selects these in turn, the randomizer selects one at random,
+ * which is used depends on the setting of the 'test_exhaustive' flag.  Notice
+ * that this function changes the colour space encoding so it must only be
+ * called on completion of the previous test.  This is what 'modifier_reset'
+ * does, below.
+ *
+ * After the function has been called the 'repeat' flag will still be set; the
+ * caller of modifier_reset must reset it at the start of each run of the test!
+ */
+static unsigned int
+modifier_total_encodings(PNG_CONST png_modifier *pm)
+{
+   return 1 +                 /* (1) nothing */
+      pm->ngammas +           /* (2) gamma values to test */
+      pm->nencodings +        /* (3) total number of encodings */
+      /* The following test only works after the first time through the
+       * png_modifier code because 'bit_depth' is set when the IHDR is read.
+       * modifier_reset, below, preserves the setting until after it has called
+       * the iterate function (also below.)
+       *
+       * For this reason do not rely on this function outside a call to
+       * modifier_reset.
+       */
+      ((pm->bit_depth == 16 || pm->assume_16_bit_calculations) ?
+         pm->nencodings : 0); /* (4) encodings with gamma == 1.0 */
+}
+
+static void
+modifier_encoding_iterate(png_modifier *pm)
+{
+   if (!pm->repeat && /* Else something needs the current encoding again. */
+      pm->test_uses_encoding) /* Some transform is encoding dependent */
+   {
+      if (pm->test_exhaustive)
+      {
+         if (++pm->encoding_counter >= modifier_total_encodings(pm))
+            pm->encoding_counter = 0; /* This will stop the repeat */
+      }
+
+      else
+      {
+         /* Not exhaustive - choose an encoding at random; generate a number in
+          * the range 1..(max-1), so the result is always non-zero:
+          */
+         if (pm->encoding_counter == 0)
+            pm->encoding_counter = random_mod(modifier_total_encodings(pm)-1)+1;
+         else
+            pm->encoding_counter = 0;
+      }
+
+      if (pm->encoding_counter > 0)
+         pm->repeat = 1;
+   }
+
+   else if (!pm->repeat)
+      pm->encoding_counter = 0;
+}
+
+static void
+modifier_reset(png_modifier *pm)
+{
+   store_read_reset(&pm->this);
+   pm->limit = 4E-3;
+   pm->pending_len = pm->pending_chunk = 0;
+   pm->flush = pm->buffer_count = pm->buffer_position = 0;
+   pm->modifications = NULL;
+   pm->state = modifier_start;
+   modifier_encoding_iterate(pm);
+   /* The following must be set in the next run.  In particular
+    * test_uses_encodings must be set in the _ini function of each transform
+    * that looks at the encodings.  (Not the 'add' function!)
+    */
+   pm->test_uses_encoding = 0;
+   pm->current_gamma = 0;
+   pm->current_encoding = 0;
+   pm->encoding_ignored = 0;
+   /* These only become value after IHDR is read: */
+   pm->bit_depth = pm->colour_type = 0;
+}
+
+/* The following must be called before anything else to get the encoding set up
+ * on the modifier.  In particular it must be called before the transform init
+ * functions are called.
+ */
+static void
+modifier_set_encoding(png_modifier *pm)
+{
+   /* Set the encoding to the one specified by the current encoding counter,
+    * first clear out all the settings - this corresponds to an encoding_counter
+    * of 0.
+    */
+   pm->current_gamma = 0;
+   pm->current_encoding = 0;
+   pm->encoding_ignored = 0; /* not ignored yet - happens in _ini functions. */
+
+   /* Now, if required, set the gamma and encoding fields. */
+   if (pm->encoding_counter > 0)
+   {
+      /* The gammas[] array is an array of screen gammas, not encoding gammas,
+       * so we need the inverse:
+       */
+      if (pm->encoding_counter <= pm->ngammas)
+         pm->current_gamma = 1/pm->gammas[pm->encoding_counter-1];
+
+      else
+      {
+         unsigned int i = pm->encoding_counter - pm->ngammas;
+
+         if (i >= pm->nencodings)
+         {
+            i %= pm->nencodings;
+            pm->current_gamma = 1; /* Linear, only in the 16 bit case */
+         }
+
+         else
+            pm->current_gamma = pm->encodings[i].gamma;
+
+         pm->current_encoding = pm->encodings + i;
+      }
+   }
+}
+
+/* Enquiry functions to find out what is set.  Notice that there is an implicit
+ * assumption below that the first encoding in the list is the one for sRGB.
+ */
+static int
+modifier_color_encoding_is_sRGB(PNG_CONST png_modifier *pm)
+{
+   return pm->current_encoding != 0 && pm->current_encoding == pm->encodings &&
+      pm->current_encoding->gamma == pm->current_gamma;
+}
+
+static int
+modifier_color_encoding_is_set(PNG_CONST png_modifier *pm)
+{
+   return pm->current_gamma != 0;
+}
+
+/* Convenience macros. */
+#define CHUNK(a,b,c,d) (((a)<<24)+((b)<<16)+((c)<<8)+(d))
+#define CHUNK_IHDR CHUNK(73,72,68,82)
+#define CHUNK_PLTE CHUNK(80,76,84,69)
+#define CHUNK_IDAT CHUNK(73,68,65,84)
+#define CHUNK_IEND CHUNK(73,69,78,68)
+#define CHUNK_cHRM CHUNK(99,72,82,77)
+#define CHUNK_gAMA CHUNK(103,65,77,65)
+#define CHUNK_sBIT CHUNK(115,66,73,84)
+#define CHUNK_sRGB CHUNK(115,82,71,66)
+
+/* The guts of modification are performed during a read. */
+static void
+modifier_crc(png_bytep buffer)
+{
+   /* Recalculate the chunk CRC - a complete chunk must be in
+    * the buffer, at the start.
+    */
+   uInt datalen = png_get_uint_32(buffer);
+   uLong crc = crc32(0, buffer+4, datalen+4);
+   /* The cast to png_uint_32 is safe because a crc32 is always a 32 bit value.
+    */
+   png_save_uint_32(buffer+datalen+8, (png_uint_32)crc);
+}
+
+static void
+modifier_setbuffer(png_modifier *pm)
+{
+   modifier_crc(pm->buffer);
+   pm->buffer_count = png_get_uint_32(pm->buffer)+12;
+   pm->buffer_position = 0;
+}
+
+/* Separate the callback into the actual implementation (which is passed the
+ * png_modifier explicitly) and the callback, which gets the modifier from the
+ * png_struct.
+ */
+static void
+modifier_read_imp(png_modifier *pm, png_bytep pb, png_size_t st)
+{
+   while (st > 0)
+   {
+      size_t cb;
+      png_uint_32 len, chunk;
+      png_modification *mod;
+
+      if (pm->buffer_position >= pm->buffer_count) switch (pm->state)
+      {
+         static png_byte sign[8] = { 137, 80, 78, 71, 13, 10, 26, 10 };
+         case modifier_start:
+            store_read_imp(&pm->this, pm->buffer, 8); /* size of signature. */
+            pm->buffer_count = 8;
+            pm->buffer_position = 0;
+
+            if (memcmp(pm->buffer, sign, 8) != 0)
+               png_error(pm->this.pread, "invalid PNG file signature");
+            pm->state = modifier_signature;
+            break;
+
+         case modifier_signature:
+            store_read_imp(&pm->this, pm->buffer, 13+12); /* size of IHDR */
+            pm->buffer_count = 13+12;
+            pm->buffer_position = 0;
+
+            if (png_get_uint_32(pm->buffer) != 13 ||
+                png_get_uint_32(pm->buffer+4) != CHUNK_IHDR)
+               png_error(pm->this.pread, "invalid IHDR");
+
+            /* Check the list of modifiers for modifications to the IHDR. */
+            mod = pm->modifications;
+            while (mod != NULL)
+            {
+               if (mod->chunk == CHUNK_IHDR && mod->modify_fn &&
+                   (*mod->modify_fn)(pm, mod, 0))
+                  {
+                  mod->modified = 1;
+                  modifier_setbuffer(pm);
+                  }
+
+               /* Ignore removal or add if IHDR! */
+               mod = mod->next;
+            }
+
+            /* Cache information from the IHDR (the modified one.) */
+            pm->bit_depth = pm->buffer[8+8];
+            pm->colour_type = pm->buffer[8+8+1];
+
+            pm->state = modifier_IHDR;
+            pm->flush = 0;
+            break;
+
+         case modifier_IHDR:
+         default:
+            /* Read a new chunk and process it until we see PLTE, IDAT or
+             * IEND.  'flush' indicates that there is still some data to
+             * output from the preceding chunk.
+             */
+            if ((cb = pm->flush) > 0)
+            {
+               if (cb > st) cb = st;
+               pm->flush -= cb;
+               store_read_imp(&pm->this, pb, cb);
+               pb += cb;
+               st -= cb;
+               if (st == 0) return;
+            }
+
+            /* No more bytes to flush, read a header, or handle a pending
+             * chunk.
+             */
+            if (pm->pending_chunk != 0)
+            {
+               png_save_uint_32(pm->buffer, pm->pending_len);
+               png_save_uint_32(pm->buffer+4, pm->pending_chunk);
+               pm->pending_len = 0;
+               pm->pending_chunk = 0;
+            }
+            else
+               store_read_imp(&pm->this, pm->buffer, 8);
+
+            pm->buffer_count = 8;
+            pm->buffer_position = 0;
+
+            /* Check for something to modify or a terminator chunk. */
+            len = png_get_uint_32(pm->buffer);
+            chunk = png_get_uint_32(pm->buffer+4);
+
+            /* Terminators first, they may have to be delayed for added
+             * chunks
+             */
+            if (chunk == CHUNK_PLTE || chunk == CHUNK_IDAT ||
+                chunk == CHUNK_IEND)
+            {
+               mod = pm->modifications;
+
+               while (mod != NULL)
+               {
+                  if ((mod->add == chunk ||
+                      (mod->add == CHUNK_PLTE && chunk == CHUNK_IDAT)) &&
+                      mod->modify_fn != NULL && !mod->modified && !mod->added)
+                  {
+                     /* Regardless of what the modify function does do not run
+                      * this again.
+                      */
+                     mod->added = 1;
+
+                     if ((*mod->modify_fn)(pm, mod, 1 /*add*/))
+                     {
+                        /* Reset the CRC on a new chunk */
+                        if (pm->buffer_count > 0)
+                           modifier_setbuffer(pm);
+
+                        else
+                           {
+                           pm->buffer_position = 0;
+                           mod->removed = 1;
+                           }
+
+                        /* The buffer has been filled with something (we assume)
+                         * so output this.  Pend the current chunk.
+                         */
+                        pm->pending_len = len;
+                        pm->pending_chunk = chunk;
+                        break; /* out of while */
+                     }
+                  }
+
+                  mod = mod->next;
+               }
+
+               /* Don't do any further processing if the buffer was modified -
+                * otherwise the code will end up modifying a chunk that was
+                * just added.
+                */
+               if (mod != NULL)
+                  break; /* out of switch */
+            }
+
+            /* If we get to here then this chunk may need to be modified.  To
+             * do this it must be less than 1024 bytes in total size, otherwise
+             * it just gets flushed.
+             */
+            if (len+12 <= sizeof pm->buffer)
+            {
+               store_read_imp(&pm->this, pm->buffer+pm->buffer_count,
+                   len+12-pm->buffer_count);
+               pm->buffer_count = len+12;
+
+               /* Check for a modification, else leave it be. */
+               mod = pm->modifications;
+               while (mod != NULL)
+               {
+                  if (mod->chunk == chunk)
+                  {
+                     if (mod->modify_fn == NULL)
+                     {
+                        /* Remove this chunk */
+                        pm->buffer_count = pm->buffer_position = 0;
+                        mod->removed = 1;
+                        break; /* Terminate the while loop */
+                     }
+
+                     else if ((*mod->modify_fn)(pm, mod, 0))
+                     {
+                        mod->modified = 1;
+                        /* The chunk may have been removed: */
+                        if (pm->buffer_count == 0)
+                        {
+                           pm->buffer_position = 0;
+                           break;
+                        }
+                        modifier_setbuffer(pm);
+                     }
+                  }
+
+                  mod = mod->next;
+               }
+            }
+
+            else
+               pm->flush = len+12 - pm->buffer_count; /* data + crc */
+
+            /* Take the data from the buffer (if there is any). */
+            break;
+      }
+
+      /* Here to read from the modifier buffer (not directly from
+       * the store, as in the flush case above.)
+       */
+      cb = pm->buffer_count - pm->buffer_position;
+
+      if (cb > st)
+         cb = st;
+
+      memcpy(pb, pm->buffer + pm->buffer_position, cb);
+      st -= cb;
+      pb += cb;
+      pm->buffer_position += cb;
+   }
+}
+
+/* The callback: */
+static void
+modifier_read(png_structp pp, png_bytep pb, png_size_t st)
+{
+   png_modifier *pm = voidcast(png_modifier*, png_get_io_ptr(pp));
+
+   if (pm == NULL || pm->this.pread != pp)
+      png_error(pp, "bad modifier_read call");
+
+   modifier_read_imp(pm, pb, st);
+}
+
+/* Like store_progressive_read but the data is getting changed as we go so we
+ * need a local buffer.
+ */
+static void
+modifier_progressive_read(png_modifier *pm, png_structp pp, png_infop pi)
+{
+   if (pm->this.pread != pp || pm->this.current == NULL ||
+       pm->this.next == NULL)
+      png_error(pp, "store state damaged (progressive)");
+
+   /* This is another Horowitz and Hill random noise generator.  In this case
+    * the aim is to stress the progressive reader with truly horrible variable
+    * buffer sizes in the range 1..500, so a sequence of 9 bit random numbers
+    * is generated.  We could probably just count from 1 to 32767 and get as
+    * good a result.
+    */
+   for (;;)
+   {
+      static png_uint_32 noise = 1;
+      png_size_t cb, cbAvail;
+      png_byte buffer[512];
+
+      /* Generate 15 more bits of stuff: */
+      noise = (noise << 9) | ((noise ^ (noise >> (9-5))) & 0x1ff);
+      cb = noise & 0x1ff;
+
+      /* Check that this number of bytes are available (in the current buffer.)
+       * (This doesn't quite work - the modifier might delete a chunk; unlikely
+       * but possible, it doesn't happen at present because the modifier only
+       * adds chunks to standard images.)
+       */
+      cbAvail = store_read_buffer_avail(&pm->this);
+      if (pm->buffer_count > pm->buffer_position)
+         cbAvail += pm->buffer_count - pm->buffer_position;
+
+      if (cb > cbAvail)
+      {
+         /* Check for EOF: */
+         if (cbAvail == 0)
+            break;
+
+         cb = cbAvail;
+      }
+
+      modifier_read_imp(pm, buffer, cb);
+      png_process_data(pp, pi, buffer, cb);
+   }
+
+   /* Check the invariants at the end (if this fails it's a problem in this
+    * file!)
+    */
+   if (pm->buffer_count > pm->buffer_position ||
+       pm->this.next != &pm->this.current->data ||
+       pm->this.readpos < pm->this.current->datacount)
+      png_error(pp, "progressive read implementation error");
+}
+
+/* Set up a modifier. */
+static png_structp
+set_modifier_for_read(png_modifier *pm, png_infopp ppi, png_uint_32 id,
+    PNG_CONST char *name)
+{
+   /* Do this first so that the modifier fields are cleared even if an error
+    * happens allocating the png_struct.  No allocation is done here so no
+    * cleanup is required.
+    */
+   pm->state = modifier_start;
+   pm->bit_depth = 0;
+   pm->colour_type = 255;
+
+   pm->pending_len = 0;
+   pm->pending_chunk = 0;
+   pm->flush = 0;
+   pm->buffer_count = 0;
+   pm->buffer_position = 0;
+
+   return set_store_for_read(&pm->this, ppi, id, name);
+}
+
+
+/******************************** MODIFICATIONS *******************************/
+/* Standard modifications to add chunks.  These do not require the _SUPPORTED
+ * macros because the chunks can be there regardless of whether this specific
+ * libpng supports them.
+ */
+typedef struct gama_modification
+{
+   png_modification this;
+   png_fixed_point  gamma;
+} gama_modification;
+
+static int
+gama_modify(png_modifier *pm, png_modification *me, int add)
+{
+   UNUSED(add)
+   /* This simply dumps the given gamma value into the buffer. */
+   png_save_uint_32(pm->buffer, 4);
+   png_save_uint_32(pm->buffer+4, CHUNK_gAMA);
+   png_save_uint_32(pm->buffer+8, ((gama_modification*)me)->gamma);
+   return 1;
+}
+
+static void
+gama_modification_init(gama_modification *me, png_modifier *pm, double gammad)
+{
+   double g;
+
+   modification_init(&me->this);
+   me->this.chunk = CHUNK_gAMA;
+   me->this.modify_fn = gama_modify;
+   me->this.add = CHUNK_PLTE;
+   g = fix(gammad);
+   me->gamma = (png_fixed_point)g;
+   me->this.next = pm->modifications;
+   pm->modifications = &me->this;
+}
+
+typedef struct chrm_modification
+{
+   png_modification          this;
+   PNG_CONST color_encoding *encoding;
+   png_fixed_point           wx, wy, rx, ry, gx, gy, bx, by;
+} chrm_modification;
+
+static int
+chrm_modify(png_modifier *pm, png_modification *me, int add)
+{
+   UNUSED(add)
+   /* As with gAMA this just adds the required cHRM chunk to the buffer. */
+   png_save_uint_32(pm->buffer   , 32);
+   png_save_uint_32(pm->buffer+ 4, CHUNK_cHRM);
+   png_save_uint_32(pm->buffer+ 8, ((chrm_modification*)me)->wx);
+   png_save_uint_32(pm->buffer+12, ((chrm_modification*)me)->wy);
+   png_save_uint_32(pm->buffer+16, ((chrm_modification*)me)->rx);
+   png_save_uint_32(pm->buffer+20, ((chrm_modification*)me)->ry);
+   png_save_uint_32(pm->buffer+24, ((chrm_modification*)me)->gx);
+   png_save_uint_32(pm->buffer+28, ((chrm_modification*)me)->gy);
+   png_save_uint_32(pm->buffer+32, ((chrm_modification*)me)->bx);
+   png_save_uint_32(pm->buffer+36, ((chrm_modification*)me)->by);
+   return 1;
+}
+
+static void
+chrm_modification_init(chrm_modification *me, png_modifier *pm,
+   PNG_CONST color_encoding *encoding)
+{
+   CIE_color white = white_point(encoding);
+
+   /* Original end points: */
+   me->encoding = encoding;
+
+   /* Chromaticities (in fixed point): */
+   me->wx = fix(chromaticity_x(white));
+   me->wy = fix(chromaticity_y(white));
+
+   me->rx = fix(chromaticity_x(encoding->red));
+   me->ry = fix(chromaticity_y(encoding->red));
+   me->gx = fix(chromaticity_x(encoding->green));
+   me->gy = fix(chromaticity_y(encoding->green));
+   me->bx = fix(chromaticity_x(encoding->blue));
+   me->by = fix(chromaticity_y(encoding->blue));
+
+   modification_init(&me->this);
+   me->this.chunk = CHUNK_cHRM;
+   me->this.modify_fn = chrm_modify;
+   me->this.add = CHUNK_PLTE;
+   me->this.next = pm->modifications;
+   pm->modifications = &me->this;
+}
+
+typedef struct srgb_modification
+{
+   png_modification this;
+   png_byte         intent;
+} srgb_modification;
+
+static int
+srgb_modify(png_modifier *pm, png_modification *me, int add)
+{
+   UNUSED(add)
+   /* As above, ignore add and just make a new chunk */
+   png_save_uint_32(pm->buffer, 1);
+   png_save_uint_32(pm->buffer+4, CHUNK_sRGB);
+   pm->buffer[8] = ((srgb_modification*)me)->intent;
+   return 1;
+}
+
+static void
+srgb_modification_init(srgb_modification *me, png_modifier *pm, png_byte intent)
+{
+   modification_init(&me->this);
+   me->this.chunk = CHUNK_sBIT;
+
+   if (intent <= 3) /* if valid, else *delete* sRGB chunks */
+   {
+      me->this.modify_fn = srgb_modify;
+      me->this.add = CHUNK_PLTE;
+      me->intent = intent;
+   }
+
+   else
+   {
+      me->this.modify_fn = 0;
+      me->this.add = 0;
+      me->intent = 0;
+   }
+
+   me->this.next = pm->modifications;
+   pm->modifications = &me->this;
+}
+
+typedef struct sbit_modification
+{
+   png_modification this;
+   png_byte         sbit;
+} sbit_modification;
+
+static int
+sbit_modify(png_modifier *pm, png_modification *me, int add)
+{
+   png_byte sbit = ((sbit_modification*)me)->sbit;
+   if (pm->bit_depth > sbit)
+   {
+      int cb = 0;
+      switch (pm->colour_type)
+      {
+         case 0:
+            cb = 1;
+            break;
+
+         case 2:
+         case 3:
+            cb = 3;
+            break;
+
+         case 4:
+            cb = 2;
+            break;
+
+         case 6:
+            cb = 4;
+            break;
+
+         default:
+            png_error(pm->this.pread,
+               "unexpected colour type in sBIT modification");
+      }
+
+      png_save_uint_32(pm->buffer, cb);
+      png_save_uint_32(pm->buffer+4, CHUNK_sBIT);
+
+      while (cb > 0)
+         (pm->buffer+8)[--cb] = sbit;
+
+      return 1;
+   }
+   else if (!add)
+   {
+      /* Remove the sBIT chunk */
+      pm->buffer_count = pm->buffer_position = 0;
+      return 1;
+   }
+   else
+      return 0; /* do nothing */
+}
+
+static void
+sbit_modification_init(sbit_modification *me, png_modifier *pm, png_byte sbit)
+{
+   modification_init(&me->this);
+   me->this.chunk = CHUNK_sBIT;
+   me->this.modify_fn = sbit_modify;
+   me->this.add = CHUNK_PLTE;
+   me->sbit = sbit;
+   me->this.next = pm->modifications;
+   pm->modifications = &me->this;
+}
+#endif /* PNG_READ_TRANSFORMS_SUPPORTED */
+
+/***************************** STANDARD PNG FILES *****************************/
+/* Standard files - write and save standard files. */
+/* There are two basic forms of standard images.  Those which attempt to have
+ * all the possible pixel values (not possible for 16bpp images, but a range of
+ * values are produced) and those which have a range of image sizes.  The former
+ * are used for testing transforms, in particular gamma correction and bit
+ * reduction and increase.  The latter are reserved for testing the behavior of
+ * libpng with respect to 'odd' image sizes - particularly small images where
+ * rows become 1 byte and interlace passes disappear.
+ *
+ * The first, most useful, set are the 'transform' images, the second set of
+ * small images are the 'size' images.
+ *
+ * The transform files are constructed with rows which fit into a 1024 byte row
+ * buffer.  This makes allocation easier below.  Further regardless of the file
+ * format every row has 128 pixels (giving 1024 bytes for 64bpp formats).
+ *
+ * Files are stored with no gAMA or sBIT chunks, with a PLTE only when needed
+ * and with an ID derived from the colour type, bit depth and interlace type
+ * as above (FILEID).  The width (128) and height (variable) are not stored in
+ * the FILEID - instead the fields are set to 0, indicating a transform file.
+ *
+ * The size files ar constructed with rows a maximum of 128 bytes wide, allowing
+ * a maximum width of 16 pixels (for the 64bpp case.)  They also have a maximum
+ * height of 16 rows.  The width and height are stored in the FILEID and, being
+ * non-zero, indicate a size file.
+ *
+ * For palette image (colour type 3) multiple transform images are stored with
+ * the same bit depth to allow testing of more colour combinations -
+ * particularly important for testing the gamma code because libpng uses a
+ * different code path for palette images.  For size images a single palette is
+ * used.
+ */
+
+/* Make a 'standard' palette.  Because there are only 256 entries in a palette
+ * (maximum) this actually makes a random palette in the hope that enough tests
+ * will catch enough errors.  (Note that the same palette isn't produced every
+ * time for the same test - it depends on what previous tests have been run -
+ * but a given set of arguments to pngvalid will always produce the same palette
+ * at the same test!  This is why pseudo-random number generators are useful for
+ * testing.)
+ *
+ * The store must be open for write when this is called, otherwise an internal
+ * error will occur.  This routine contains its own magic number seed, so the
+ * palettes generated don't change if there are intervening errors (changing the
+ * calls to the store_mark seed.)
+ */
+static store_palette_entry *
+make_standard_palette(png_store* ps, int npalette, int do_tRNS)
+{
+   static png_uint_32 palette_seed[2] = { 0x87654321, 9 };
+
+   int i = 0;
+   png_byte values[256][4];
+
+   /* Always put in black and white plus the six primary and secondary colors.
+    */
+   for (; i<8; ++i)
+   {
+      values[i][1] = (i&1) ? 255 : 0;
+      values[i][2] = (i&2) ? 255 : 0;
+      values[i][3] = (i&4) ? 255 : 0;
+   }
+
+   /* Then add 62 grays (one quarter of the remaining 256 slots). */
+   {
+      int j = 0;
+      png_byte random_bytes[4];
+      png_byte need[256];
+
+      need[0] = 0; /*got black*/
+      memset(need+1, 1, (sizeof need)-2); /*need these*/
+      need[255] = 0; /*but not white*/
+
+      while (i<70)
+      {
+         png_byte b;
+
+         if (j==0)
+         {
+            make_four_random_bytes(palette_seed, random_bytes);
+            j = 4;
+         }
+
+         b = random_bytes[--j];
+         if (need[b])
+         {
+            values[i][1] = b;
+            values[i][2] = b;
+            values[i++][3] = b;
+         }
+      }
+   }
+
+   /* Finally add 192 colors at random - don't worry about matches to things we
+    * already have, chance is less than 1/65536.  Don't worry about grays,
+    * chance is the same, so we get a duplicate or extra gray less than 1 time
+    * in 170.
+    */
+   for (; i<256; ++i)
+      make_four_random_bytes(palette_seed, values[i]);
+
+   /* Fill in the alpha values in the first byte.  Just use all possible values
+    * (0..255) in an apparently random order:
+    */
+   {
+      store_palette_entry *palette;
+      png_byte selector[4];
+
+      make_four_random_bytes(palette_seed, selector);
+
+      if (do_tRNS)
+         for (i=0; i<256; ++i)
+            values[i][0] = (png_byte)(i ^ selector[0]);
+
+      else
+         for (i=0; i<256; ++i)
+            values[i][0] = 255; /* no transparency/tRNS chunk */
+
+      /* 'values' contains 256 ARGB values, but we only need 'npalette'.
+       * 'npalette' will always be a power of 2: 2, 4, 16 or 256.  In the low
+       * bit depth cases select colors at random, else it is difficult to have
+       * a set of low bit depth palette test with any chance of a reasonable
+       * range of colors.  Do this by randomly permuting values into the low
+       * 'npalette' entries using an XOR mask generated here.  This also
+       * permutes the npalette == 256 case in a potentially useful way (there is
+       * no relationship between palette index and the color value therein!)
+       */
+      palette = store_write_palette(ps, npalette);
+
+      for (i=0; i<npalette; ++i)
+      {
+         palette[i].alpha = values[i ^ selector[1]][0];
+         palette[i].red   = values[i ^ selector[1]][1];
+         palette[i].green = values[i ^ selector[1]][2];
+         palette[i].blue  = values[i ^ selector[1]][3];
+      }
+
+      return palette;
+   }
+}
+
+/* Initialize a standard palette on a write stream.  The 'do_tRNS' argument
+ * indicates whether or not to also set the tRNS chunk.
+ */
+static void
+init_standard_palette(png_store *ps, png_structp pp, png_infop pi, int npalette,
+   int do_tRNS)
+{
+   store_palette_entry *ppal = make_standard_palette(ps, npalette, do_tRNS);
+
+   {
+      int i;
+      png_color palette[256];
+
+      /* Set all entries to detect overread errors. */
+      for (i=0; i<npalette; ++i)
+      {
+         palette[i].red = ppal[i].red;
+         palette[i].green = ppal[i].green;
+         palette[i].blue = ppal[i].blue;
+      }
+
+      /* Just in case fill in the rest with detectable values: */
+      for (; i<256; ++i)
+         palette[i].red = palette[i].green = palette[i].blue = 42;
+
+      png_set_PLTE(pp, pi, palette, npalette);
+   }
+
+   if (do_tRNS)
+   {
+      int i, j;
+      png_byte tRNS[256];
+
+      /* Set all the entries, but skip trailing opaque entries */
+      for (i=j=0; i<npalette; ++i)
+         if ((tRNS[i] = ppal[i].alpha) < 255)
+            j = i+1;
+
+      /* Fill in the remainder with a detectable value: */
+      for (; i<256; ++i)
+         tRNS[i] = 24;
+
+      if (j > 0)
+         png_set_tRNS(pp, pi, tRNS, j, 0/*color*/);
+   }
+}
+
+/* The number of passes is related to the interlace type. There was no libpng
+ * API to determine this prior to 1.5, so we need an inquiry function:
+ */
+static int
+npasses_from_interlace_type(png_structp pp, int interlace_type)
+{
+   switch (interlace_type)
+   {
+   default:
+      png_error(pp, "invalid interlace type");
+
+   case PNG_INTERLACE_NONE:
+      return 1;
+
+   case PNG_INTERLACE_ADAM7:
+      return PNG_INTERLACE_ADAM7_PASSES;
+   }
+}
+
+static unsigned int
+bit_size(png_structp pp, png_byte colour_type, png_byte bit_depth)
+{
+   switch (colour_type)
+   {
+      default: png_error(pp, "invalid color type");
+
+      case 0:  return bit_depth;
+
+      case 2:  return 3*bit_depth;
+
+      case 3:  return bit_depth;
+
+      case 4:  return 2*bit_depth;
+
+      case 6:  return 4*bit_depth;
+   }
+}
+
+#define TRANSFORM_WIDTH  128U
+#define TRANSFORM_ROWMAX (TRANSFORM_WIDTH*8U)
+#define SIZE_ROWMAX (16*8U) /* 16 pixels, max 8 bytes each - 128 bytes */
+#define STANDARD_ROWMAX TRANSFORM_ROWMAX /* The larger of the two */
+#define SIZE_HEIGHTMAX 16 /* Maximum range of size images */
+
+static size_t
+transform_rowsize(png_structp pp, png_byte colour_type, png_byte bit_depth)
+{
+   return (TRANSFORM_WIDTH * bit_size(pp, colour_type, bit_depth)) / 8;
+}
+
+/* transform_width(pp, colour_type, bit_depth) current returns the same number
+ * every time, so just use a macro:
+ */
+#define transform_width(pp, colour_type, bit_depth) TRANSFORM_WIDTH
+
+static png_uint_32
+transform_height(png_structp pp, png_byte colour_type, png_byte bit_depth)
+{
+   switch (bit_size(pp, colour_type, bit_depth))
+   {
+      case 1:
+      case 2:
+      case 4:
+         return 1;   /* Total of 128 pixels */
+
+      case 8:
+         return 2;   /* Total of 256 pixels/bytes */
+
+      case 16:
+         return 512; /* Total of 65536 pixels */
+
+      case 24:
+      case 32:
+         return 512; /* 65536 pixels */
+
+      case 48:
+      case 64:
+         return 2048;/* 4 x 65536 pixels. */
+#        define TRANSFORM_HEIGHTMAX 2048
+
+      default:
+         return 0;   /* Error, will be caught later */
+   }
+}
+
+/* The following can only be defined here, now we have the definitions
+ * of the transform image sizes.
+ */
+static png_uint_32
+standard_width(png_structp pp, png_uint_32 id)
+{
+   png_uint_32 width = WIDTH_FROM_ID(id);
+   UNUSED(pp)
+
+   if (width == 0)
+      width = transform_width(pp, COL_FROM_ID(id), DEPTH_FROM_ID(id));
+
+   return width;
+}
+
+static png_uint_32
+standard_height(png_structp pp, png_uint_32 id)
+{
+   png_uint_32 height = HEIGHT_FROM_ID(id);
+
+   if (height == 0)
+      height = transform_height(pp, COL_FROM_ID(id), DEPTH_FROM_ID(id));
+
+   return height;
+}
+
+static png_uint_32
+standard_rowsize(png_structp pp, png_uint_32 id)
+{
+   png_uint_32 width = standard_width(pp, id);
+
+   /* This won't overflow: */
+   width *= bit_size(pp, COL_FROM_ID(id), DEPTH_FROM_ID(id));
+   return (width + 7) / 8;
+}
+
+static void
+transform_row(png_structp pp, png_byte buffer[TRANSFORM_ROWMAX],
+   png_byte colour_type, png_byte bit_depth, png_uint_32 y)
+{
+   png_uint_32 v = y << 7;
+   png_uint_32 i = 0;
+
+   switch (bit_size(pp, colour_type, bit_depth))
+   {
+      case 1:
+         while (i<128/8) buffer[i] = v & 0xff, v += 17, ++i;
+         return;
+
+      case 2:
+         while (i<128/4) buffer[i] = v & 0xff, v += 33, ++i;
+         return;
+
+      case 4:
+         while (i<128/2) buffer[i] = v & 0xff, v += 65, ++i;
+         return;
+
+      case 8:
+         /* 256 bytes total, 128 bytes in each row set as follows: */
+         while (i<128) buffer[i] = v & 0xff, ++v, ++i;
+         return;
+
+      case 16:
+         /* Generate all 65536 pixel values in order, which includes the 8 bit
+          * GA case as well as the 16 bit G case.
+          */
+         while (i<128)
+            buffer[2*i] = (v>>8) & 0xff, buffer[2*i+1] = v & 0xff, ++v, ++i;
+
+         return;
+
+      case 24:
+         /* 65535 pixels, but rotate the values. */
+         while (i<128)
+         {
+            /* Three bytes per pixel, r, g, b, make b by r^g */
+            buffer[3*i+0] = (v >> 8) & 0xff;
+            buffer[3*i+1] = v & 0xff;
+            buffer[3*i+2] = ((v >> 8) ^ v) & 0xff;
+            ++v;
+            ++i;
+         }
+
+         return;
+
+      case 32:
+         /* 65535 pixels, r, g, b, a; just replicate */
+         while (i<128)
+         {
+            buffer[4*i+0] = (v >> 8) & 0xff;
+            buffer[4*i+1] = v & 0xff;
+            buffer[4*i+2] = (v >> 8) & 0xff;
+            buffer[4*i+3] = v & 0xff;
+            ++v;
+            ++i;
+         }
+
+         return;
+
+      case 48:
+         /* y is maximum 2047, giving 4x65536 pixels, make 'r' increase by 1 at
+          * each pixel, g increase by 257 (0x101) and 'b' by 0x1111:
+          */
+         while (i<128)
+         {
+            png_uint_32 t = v++;
+            buffer[6*i+0] = (t >> 8) & 0xff;
+            buffer[6*i+1] = t & 0xff;
+            t *= 257;
+            buffer[6*i+2] = (t >> 8) & 0xff;
+            buffer[6*i+3] = t & 0xff;
+            t *= 17;
+            buffer[6*i+4] = (t >> 8) & 0xff;
+            buffer[6*i+5] = t & 0xff;
+            ++i;
+         }
+
+         return;
+
+      case 64:
+         /* As above in the 32 bit case. */
+         while (i<128)
+         {
+            png_uint_32 t = v++;
+            buffer[8*i+0] = (t >> 8) & 0xff;
+            buffer[8*i+1] = t & 0xff;
+            buffer[8*i+4] = (t >> 8) & 0xff;
+            buffer[8*i+5] = t & 0xff;
+            t *= 257;
+            buffer[8*i+2] = (t >> 8) & 0xff;
+            buffer[8*i+3] = t & 0xff;
+            buffer[8*i+6] = (t >> 8) & 0xff;
+            buffer[8*i+7] = t & 0xff;
+            ++i;
+         }
+         return;
+
+      default:
+         break;
+   }
+
+   png_error(pp, "internal error");
+}
+
+/* This is just to do the right cast - could be changed to a function to check
+ * 'bd' but there isn't much point.
+ */
+#define DEPTH(bd) ((png_byte)(1U << (bd)))
+
+/* Make a standardized image given a an image colour type, bit depth and
+ * interlace type.  The standard images have a very restricted range of
+ * rows and heights and are used for testing transforms rather than image
+ * layout details.  See make_size_images below for a way to make images
+ * that test odd sizes along with the libpng interlace handling.
+ */
+static void
+make_transform_image(png_store* PNG_CONST ps, png_byte PNG_CONST colour_type,
+    png_byte PNG_CONST bit_depth, int palette_number, int interlace_type,
+    png_const_charp name)
+{
+   context(ps, fault);
+
+   Try
+   {
+      png_infop pi;
+      png_structp pp = set_store_for_write(ps, &pi, name);
+      png_uint_32 h;
+
+      /* In the event of a problem return control to the Catch statement below
+       * to do the clean up - it is not possible to 'return' directly from a Try
+       * block.
+       */
+      if (pp == NULL)
+         Throw ps;
+
+      h = transform_height(pp, colour_type, bit_depth);
+
+      png_set_IHDR(pp, pi, transform_width(pp, colour_type, bit_depth), h,
+         bit_depth, colour_type, interlace_type,
+         PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
+
+#ifdef PNG_TEXT_SUPPORTED
+      {
+         static char key[] = "image name"; /* must be writeable */
+         size_t pos;
+         png_text text;
+         char copy[FILE_NAME_SIZE];
+
+         /* Use a compressed text string to test the correct interaction of text
+          * compression and IDAT compression.
+          */
+         text.compression = PNG_TEXT_COMPRESSION_zTXt;
+         text.key = key;
+         /* Yuck: the text must be writable! */
+         pos = safecat(copy, sizeof copy, 0, ps->wname);
+         text.text = copy;
+         text.text_length = pos;
+         text.itxt_length = 0;
+         text.lang = 0;
+         text.lang_key = 0;
+
+         png_set_text(pp, pi, &text, 1);
+      }
+#endif
+
+      if (colour_type == 3) /* palette */
+         init_standard_palette(ps, pp, pi, 1U << bit_depth, 1/*do tRNS*/);
+
+      png_write_info(pp, pi);
+
+      if (png_get_rowbytes(pp, pi) !=
+          transform_rowsize(pp, colour_type, bit_depth))
+         png_error(pp, "row size incorrect");
+
+      else
+      {
+         /* Somewhat confusingly this must be called *after* png_write_info
+          * because if it is called before, the information in *pp has not been
+          * updated to reflect the interlaced image.
+          */
+         int npasses = png_set_interlace_handling(pp);
+         int pass;
+
+         if (npasses != npasses_from_interlace_type(pp, interlace_type))
+            png_error(pp, "write: png_set_interlace_handling failed");
+
+         for (pass=0; pass<npasses; ++pass)
+         {
+            png_uint_32 y;
+
+            for (y=0; y<h; ++y)
+            {
+               png_byte buffer[TRANSFORM_ROWMAX];
+
+               transform_row(pp, buffer, colour_type, bit_depth, y);
+               png_write_row(pp, buffer);
+            }
+         }
+      }
+
+#ifdef PNG_TEXT_SUPPORTED
+      {
+         static char key[] = "end marker";
+         static char comment[] = "end";
+         png_text text;
+
+         /* Use a compressed text string to test the correct interaction of text
+          * compression and IDAT compression.
+          */
+         text.compression = PNG_TEXT_COMPRESSION_zTXt;
+         text.key = key;
+         text.text = comment;
+         text.text_length = (sizeof comment)-1;
+         text.itxt_length = 0;
+         text.lang = 0;
+         text.lang_key = 0;
+
+         png_set_text(pp, pi, &text, 1);
+      }
+#endif
+
+      png_write_end(pp, pi);
+
+      /* And store this under the appropriate id, then clean up. */
+      store_storefile(ps, FILEID(colour_type, bit_depth, palette_number,
+         interlace_type, 0, 0, 0));
+
+      store_write_reset(ps);
+   }
+
+   Catch(fault)
+   {
+      /* Use the png_store returned by the exception. This may help the compiler
+       * because 'ps' is not used in this branch of the setjmp.  Note that fault
+       * and ps will always be the same value.
+       */
+      store_write_reset(fault);
+   }
+}
+
+static void
+make_transform_images(png_store *ps)
+{
+   png_byte colour_type = 0;
+   png_byte bit_depth = 0;
+   int palette_number = 0;
+
+   /* This is in case of errors. */
+   safecat(ps->test, sizeof ps->test, 0, "make standard images");
+
+   /* Use next_format to enumerate all the combinations we test, including
+    * generating multiple low bit depth palette images.
+    */
+   while (next_format(&colour_type, &bit_depth, &palette_number))
+   {
+      int interlace_type;
+
+      for (interlace_type = PNG_INTERLACE_NONE;
+           interlace_type < PNG_INTERLACE_LAST; ++interlace_type)
+      {
+         char name[FILE_NAME_SIZE];
+
+         standard_name(name, sizeof name, 0, colour_type, bit_depth,
+            palette_number, interlace_type, 0, 0, 0);
+         make_transform_image(ps, colour_type, bit_depth, palette_number,
+            interlace_type, name);
+      }
+   }
+}
+
+/* The following two routines use the PNG interlace support macros from
+ * png.h to interlace or deinterlace rows.
+ */
+static void
+interlace_row(png_bytep buffer, png_const_bytep imageRow,
+   unsigned int pixel_size, png_uint_32 w, int pass)
+{
+   png_uint_32 xin, xout, xstep;
+
+   /* Note that this can, trivially, be optimized to a memcpy on pass 7, the
+    * code is presented this way to make it easier to understand.  In practice
+    * consult the code in the libpng source to see other ways of doing this.
+    */
+   xin = PNG_PASS_START_COL(pass);
+   xstep = 1U<<PNG_PASS_COL_SHIFT(pass);
+
+   for (xout=0; xin<w; xin+=xstep)
+   {
+      pixel_copy(buffer, xout, imageRow, xin, pixel_size);
+      ++xout;
+   }
+}
+
+static void
+deinterlace_row(png_bytep buffer, png_const_bytep row,
+   unsigned int pixel_size, png_uint_32 w, int pass)
+{
+   /* The inverse of the above, 'row' is part of row 'y' of the output image,
+    * in 'buffer'.  The image is 'w' wide and this is pass 'pass', distribute
+    * the pixels of row into buffer and return the number written (to allow
+    * this to be checked).
+    */
+   png_uint_32 xin, xout, xstep;
+
+   xout = PNG_PASS_START_COL(pass);
+   xstep = 1U<<PNG_PASS_COL_SHIFT(pass);
+
+   for (xin=0; xout<w; xout+=xstep)
+   {
+      pixel_copy(buffer, xout, row, xin, pixel_size);
+      ++xin;
+   }
+}
+
+/* Build a single row for the 'size' test images; this fills in only the
+ * first bit_width bits of the sample row.
+ */
+static void
+size_row(png_byte buffer[SIZE_ROWMAX], png_uint_32 bit_width, png_uint_32 y)
+{
+   /* height is in the range 1 to 16, so: */
+   y = ((y & 1) << 7) + ((y & 2) << 6) + ((y & 4) << 5) + ((y & 8) << 4);
+   /* the following ensures bits are set in small images: */
+   y ^= 0xA5;
+
+   while (bit_width >= 8)
+      *buffer++ = (png_byte)y++, bit_width -= 8;
+
+   /* There may be up to 7 remaining bits, these go in the most significant
+    * bits of the byte.
+    */
+   if (bit_width > 0)
+   {
+      png_uint_32 mask = (1U<<(8-bit_width))-1;
+      *buffer = (png_byte)((*buffer & mask) | (y & ~mask));
+   }
+}
+
+static void
+make_size_image(png_store* PNG_CONST ps, png_byte PNG_CONST colour_type,
+    png_byte PNG_CONST bit_depth, int PNG_CONST interlace_type,
+    png_uint_32 PNG_CONST w, png_uint_32 PNG_CONST h,
+    int PNG_CONST do_interlace)
+{
+   context(ps, fault);
+
+   Try
+   {
+      png_infop pi;
+      png_structp pp;
+      unsigned int pixel_size;
+
+      /* Make a name and get an appropriate id for the store: */
+      char name[FILE_NAME_SIZE];
+      PNG_CONST png_uint_32 id = FILEID(colour_type, bit_depth, 0/*palette*/,
+         interlace_type, w, h, do_interlace);
+
+      standard_name_from_id(name, sizeof name, 0, id);
+      pp = set_store_for_write(ps, &pi, name);
+
+      /* In the event of a problem return control to the Catch statement below
+       * to do the clean up - it is not possible to 'return' directly from a Try
+       * block.
+       */
+      if (pp == NULL)
+         Throw ps;
+
+      png_set_IHDR(pp, pi, w, h, bit_depth, colour_type, interlace_type,
+         PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
+
+      if (colour_type == 3) /* palette */
+         init_standard_palette(ps, pp, pi, 1U << bit_depth, 0/*do tRNS*/);
+
+      png_write_info(pp, pi);
+
+      /* Calculate the bit size, divide by 8 to get the byte size - this won't
+       * overflow because we know the w values are all small enough even for
+       * a system where 'unsigned int' is only 16 bits.
+       */
+      pixel_size = bit_size(pp, colour_type, bit_depth);
+      if (png_get_rowbytes(pp, pi) != ((w * pixel_size) + 7) / 8)
+         png_error(pp, "row size incorrect");
+
+      else
+      {
+         int npasses = npasses_from_interlace_type(pp, interlace_type);
+         png_uint_32 y;
+         int pass;
+         png_byte image[16][SIZE_ROWMAX];
+
+         /* To help consistent error detection make the parts of this buffer
+          * that aren't set below all '1':
+          */
+         memset(image, 0xff, sizeof image);
+
+         if (!do_interlace && npasses != png_set_interlace_handling(pp))
+            png_error(pp, "write: png_set_interlace_handling failed");
+
+         /* Prepare the whole image first to avoid making it 7 times: */
+         for (y=0; y<h; ++y)
+            size_row(image[y], w * pixel_size, y);
+
+         for (pass=0; pass<npasses; ++pass)
+         {
+            /* The following two are for checking the macros: */
+            PNG_CONST png_uint_32 wPass = PNG_PASS_COLS(w, pass);
+
+            /* If do_interlace is set we don't call png_write_row for every
+             * row because some of them are empty.  In fact, for a 1x1 image,
+             * most of them are empty!
+             */
+            for (y=0; y<h; ++y)
+            {
+               png_const_bytep row = image[y];
+               png_byte tempRow[SIZE_ROWMAX];
+
+               /* If do_interlace *and* the image is interlaced we
+                * need a reduced interlace row; this may be reduced
+                * to empty.
+                */
+               if (do_interlace && interlace_type == PNG_INTERLACE_ADAM7)
+               {
+                  /* The row must not be written if it doesn't exist, notice
+                   * that there are two conditions here, either the row isn't
+                   * ever in the pass or the row would be but isn't wide
+                   * enough to contribute any pixels.  In fact the wPass test
+                   * can be used to skip the whole y loop in this case.
+                   */
+                  if (PNG_ROW_IN_INTERLACE_PASS(y, pass) && wPass > 0)
+                  {
+                     /* Set to all 1's for error detection (libpng tends to
+                      * set unset things to 0).
+                      */
+                     memset(tempRow, 0xff, sizeof tempRow);
+                     interlace_row(tempRow, row, pixel_size, w, pass);
+                     row = tempRow;
+                  }
+                  else
+                     continue;
+               }
+
+               /* Only get to here if the row has some pixels in it. */
+               png_write_row(pp, row);
+            }
+         }
+      }
+
+      png_write_end(pp, pi);
+
+      /* And store this under the appropriate id, then clean up. */
+      store_storefile(ps, id);
+
+      store_write_reset(ps);
+   }
+
+   Catch(fault)
+   {
+      /* Use the png_store returned by the exception. This may help the compiler
+       * because 'ps' is not used in this branch of the setjmp.  Note that fault
+       * and ps will always be the same value.
+       */
+      store_write_reset(fault);
+   }
+}
+
+static void
+make_size(png_store* PNG_CONST ps, png_byte PNG_CONST colour_type, int bdlo,
+    int PNG_CONST bdhi)
+{
+   for (; bdlo <= bdhi; ++bdlo)
+   {
+      png_uint_32 width;
+
+      for (width = 1; width <= 16; ++width)
+      {
+         png_uint_32 height;
+
+         for (height = 1; height <= 16; ++height)
+         {
+            /* The four combinations of DIY interlace and interlace or not -
+             * no interlace + DIY should be identical to no interlace with
+             * libpng doing it.
+             */
+            make_size_image(ps, colour_type, DEPTH(bdlo), PNG_INTERLACE_NONE,
+               width, height, 0);
+            make_size_image(ps, colour_type, DEPTH(bdlo), PNG_INTERLACE_NONE,
+               width, height, 1);
+            make_size_image(ps, colour_type, DEPTH(bdlo), PNG_INTERLACE_ADAM7,
+               width, height, 0);
+            make_size_image(ps, colour_type, DEPTH(bdlo), PNG_INTERLACE_ADAM7,
+               width, height, 1);
+         }
+      }
+   }
+}
+
+static void
+make_size_images(png_store *ps)
+{
+   /* This is in case of errors. */
+   safecat(ps->test, sizeof ps->test, 0, "make size images");
+
+   /* Arguments are colour_type, low bit depth, high bit depth
+    */
+   make_size(ps, 0, 0, WRITE_BDHI);
+   make_size(ps, 2, 3, WRITE_BDHI);
+   make_size(ps, 3, 0, 3 /*palette: max 8 bits*/);
+   make_size(ps, 4, 3, WRITE_BDHI);
+   make_size(ps, 6, 3, WRITE_BDHI);
+}
+
+/* Return a row based on image id and 'y' for checking: */
+static void
+standard_row(png_structp pp, png_byte std[STANDARD_ROWMAX], png_uint_32 id,
+   png_uint_32 y)
+{
+   if (WIDTH_FROM_ID(id) == 0)
+      transform_row(pp, std, COL_FROM_ID(id), DEPTH_FROM_ID(id), y);
+   else
+      size_row(std, WIDTH_FROM_ID(id) * bit_size(pp, COL_FROM_ID(id),
+         DEPTH_FROM_ID(id)), y);
+}
+
+/* Tests - individual test cases */
+/* Like 'make_standard' but errors are deliberately introduced into the calls
+ * to ensure that they get detected - it should not be possible to write an
+ * invalid image with libpng!
+ */
+#ifdef PNG_WARNINGS_SUPPORTED
+static void
+sBIT0_error_fn(png_structp pp, png_infop pi)
+{
+   /* 0 is invalid... */
+   png_color_8 bad;
+   bad.red = bad.green = bad.blue = bad.gray = bad.alpha = 0;
+   png_set_sBIT(pp, pi, &bad);
+}
+
+static void
+sBIT_error_fn(png_structp pp, png_infop pi)
+{
+   png_byte bit_depth;
+   png_color_8 bad;
+
+   if (png_get_color_type(pp, pi) == PNG_COLOR_TYPE_PALETTE)
+      bit_depth = 8;
+
+   else
+      bit_depth = png_get_bit_depth(pp, pi);
+
+   /* Now we know the bit depth we can easily generate an invalid sBIT entry */
+   bad.red = bad.green = bad.blue = bad.gray = bad.alpha =
+      (png_byte)(bit_depth+1);
+   png_set_sBIT(pp, pi, &bad);
+}
+
+static PNG_CONST struct
+{
+   void          (*fn)(png_structp, png_infop);
+   PNG_CONST char *msg;
+   unsigned int    warning :1; /* the error is a warning... */
+} error_test[] =
+    {
+       /* no warnings makes these errors undetectable. */
+       { sBIT0_error_fn, "sBIT(0): failed to detect error", 1 },
+       { sBIT_error_fn, "sBIT(too big): failed to detect error", 1 },
+    };
+
+static void
+make_error(png_store* volatile psIn, png_byte PNG_CONST colour_type,
+    png_byte bit_depth, int interlace_type, int test, png_const_charp name)
+{
+   png_store * volatile ps = psIn;
+
+   context(ps, fault);
+
+   Try
+   {
+      png_structp pp;
+      png_infop pi;
+
+      pp = set_store_for_write(ps, &pi, name);
+
+      if (pp == NULL)
+         Throw ps;
+
+      png_set_IHDR(pp, pi, transform_width(pp, colour_type, bit_depth),
+         transform_height(pp, colour_type, bit_depth), bit_depth, colour_type,
+         interlace_type, PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
+
+      if (colour_type == 3) /* palette */
+         init_standard_palette(ps, pp, pi, 1U << bit_depth, 0/*do tRNS*/);
+
+      /* Time for a few errors; these are in various optional chunks, the
+       * standard tests test the standard chunks pretty well.
+       */
+#     define exception__prev exception_prev_1
+#     define exception__env exception_env_1
+      Try
+      {
+         /* Expect this to throw: */
+         ps->expect_error = !error_test[test].warning;
+         ps->expect_warning = error_test[test].warning;
+         ps->saw_warning = 0;
+         error_test[test].fn(pp, pi);
+
+         /* Normally the error is only detected here: */
+         png_write_info(pp, pi);
+
+         /* And handle the case where it was only a warning: */
+         if (ps->expect_warning && ps->saw_warning)
+            Throw ps;
+
+         /* If we get here there is a problem, we have success - no error or
+          * no warning - when we shouldn't have success.  Log an error.
+          */
+         store_log(ps, pp, error_test[test].msg, 1 /*error*/);
+      }
+
+      Catch (fault)
+         ps = fault; /* expected exit, make sure ps is not clobbered */
+#undef exception__prev
+#undef exception__env
+
+      /* And clear these flags */
+      ps->expect_error = 0;
+      ps->expect_warning = 0;
+
+      /* Now write the whole image, just to make sure that the detected, or
+       * undetected, errro has not created problems inside libpng.
+       */
+      if (png_get_rowbytes(pp, pi) !=
+          transform_rowsize(pp, colour_type, bit_depth))
+         png_error(pp, "row size incorrect");
+
+      else
+      {
+         png_uint_32 h = transform_height(pp, colour_type, bit_depth);
+         int npasses = png_set_interlace_handling(pp);
+         int pass;
+
+         if (npasses != npasses_from_interlace_type(pp, interlace_type))
+            png_error(pp, "write: png_set_interlace_handling failed");
+
+         for (pass=0; pass<npasses; ++pass)
+         {
+            png_uint_32 y;
+
+            for (y=0; y<h; ++y)
+            {
+               png_byte buffer[TRANSFORM_ROWMAX];
+
+               transform_row(pp, buffer, colour_type, bit_depth, y);
+               png_write_row(pp, buffer);
+            }
+         }
+      }
+
+      png_write_end(pp, pi);
+
+      /* The following deletes the file that was just written. */
+      store_write_reset(ps);
+   }
+
+   Catch(fault)
+   {
+      store_write_reset(fault);
+   }
+}
+
+static int
+make_errors(png_modifier* PNG_CONST pm, png_byte PNG_CONST colour_type,
+    int bdlo, int PNG_CONST bdhi)
+{
+   for (; bdlo <= bdhi; ++bdlo)
+   {
+      int interlace_type;
+
+      for (interlace_type = PNG_INTERLACE_NONE;
+           interlace_type < PNG_INTERLACE_LAST; ++interlace_type)
+      {
+         unsigned int test;
+         char name[FILE_NAME_SIZE];
+
+         standard_name(name, sizeof name, 0, colour_type, 1<<bdlo, 0,
+            interlace_type, 0, 0, 0);
+
+         for (test=0; test<(sizeof error_test)/(sizeof error_test[0]); ++test)
+         {
+            make_error(&pm->this, colour_type, DEPTH(bdlo), interlace_type,
+               test, name);
+
+            if (fail(pm))
+               return 0;
+         }
+      }
+   }
+
+   return 1; /* keep going */
+}
+#endif
+
+static void
+perform_error_test(png_modifier *pm)
+{
+#ifdef PNG_WARNINGS_SUPPORTED /* else there are no cases that work! */
+   /* Need to do this here because we just write in this test. */
+   safecat(pm->this.test, sizeof pm->this.test, 0, "error test");
+
+   if (!make_errors(pm, 0, 0, WRITE_BDHI))
+      return;
+
+   if (!make_errors(pm, 2, 3, WRITE_BDHI))
+      return;
+
+   if (!make_errors(pm, 3, 0, 3))
+      return;
+
+   if (!make_errors(pm, 4, 3, WRITE_BDHI))
+      return;
+
+   if (!make_errors(pm, 6, 3, WRITE_BDHI))
+      return;
+#else
+   UNUSED(pm)
+#endif
+}
+
+/* This is just to validate the internal PNG formatting code - if this fails
+ * then the warning messages the library outputs will probably be garbage.
+ */
+static void
+perform_formatting_test(png_store *volatile ps)
+{
+#ifdef PNG_TIME_RFC1123_SUPPORTED
+   /* The handle into the formatting code is the RFC1123 support; this test does
+    * nothing if that is compiled out.
+    */
+   context(ps, fault);
+
+   Try
+   {
+      png_const_charp correct = "29 Aug 2079 13:53:60 +0000";
+      png_const_charp result;
+      png_structp pp;
+      png_time pt;
+
+      pp = set_store_for_write(ps, NULL, "libpng formatting test");
+
+      if (pp == NULL)
+         Throw ps;
+
+
+      /* Arbitrary settings: */
+      pt.year = 2079;
+      pt.month = 8;
+      pt.day = 29;
+      pt.hour = 13;
+      pt.minute = 53;
+      pt.second = 60; /* a leap second */
+
+      result = png_convert_to_rfc1123(pp, &pt);
+
+      if (result == NULL)
+         png_error(pp, "png_convert_to_rfc1123 failed");
+
+      if (strcmp(result, correct) != 0)
+      {
+         size_t pos = 0;
+         char msg[128];
+
+         pos = safecat(msg, sizeof msg, pos, "png_convert_to_rfc1123(");
+         pos = safecat(msg, sizeof msg, pos, correct);
+         pos = safecat(msg, sizeof msg, pos, ") returned: '");
+         pos = safecat(msg, sizeof msg, pos, result);
+         pos = safecat(msg, sizeof msg, pos, "'");
+
+         png_error(pp, msg);
+      }
+
+      store_write_reset(ps);
+   }
+
+   Catch(fault)
+   {
+      store_write_reset(fault);
+   }
+#else
+   UNUSED(ps)
+#endif
+}
+
+/* Because we want to use the same code in both the progressive reader and the
+ * sequential reader it is necessary to deal with the fact that the progressive
+ * reader callbacks only have one parameter (png_get_progressive_ptr()), so this
+ * must contain all the test parameters and all the local variables directly
+ * accessible to the sequential reader implementation.
+ *
+ * The technique adopted is to reinvent part of what Dijkstra termed a
+ * 'display'; an array of pointers to the stack frames of enclosing functions so
+ * that a nested function definition can access the local (C auto) variables of
+ * the functions that contain its definition.  In fact C provides the first
+ * pointer (the local variables - the stack frame pointer) and the last (the
+ * global variables - the BCPL global vector typically implemented as global
+ * addresses), this code requires one more pointer to make the display - the
+ * local variables (and function call parameters) of the function that actually
+ * invokes either the progressive or sequential reader.
+ *
+ * Perhaps confusingly this technique is confounded with classes - the
+ * 'standard_display' defined here is sub-classed as the 'gamma_display' below.
+ * A gamma_display is a standard_display, taking advantage of the ANSI-C
+ * requirement that the pointer to the first member of a structure must be the
+ * same as the pointer to the structure.  This allows us to reuse standard_
+ * functions in the gamma test code; something that could not be done with
+ * nested functions!
+ */
+typedef struct standard_display
+{
+   png_store*  ps;             /* Test parameters (passed to the function) */
+   png_byte    colour_type;
+   png_byte    bit_depth;
+   png_byte    red_sBIT;       /* Input data sBIT values. */
+   png_byte    green_sBIT;
+   png_byte    blue_sBIT;
+   png_byte    alpha_sBIT;
+   int         interlace_type;
+   png_uint_32 id;             /* Calculated file ID */
+   png_uint_32 w;              /* Width of image */
+   png_uint_32 h;              /* Height of image */
+   int         npasses;        /* Number of interlaced passes */
+   png_uint_32 pixel_size;     /* Width of one pixel in bits */
+   png_uint_32 bit_width;      /* Width of output row in bits */
+   size_t      cbRow;          /* Bytes in a row of the output image */
+   int         do_interlace;   /* Do interlacing internally */
+   int         is_transparent; /* Transparency information was present. */
+   int         speed;          /* Doing a speed test */
+   int         use_update_info;/* Call update_info, not start_image */
+   struct
+   {
+      png_uint_16 red;
+      png_uint_16 green;
+      png_uint_16 blue;
+   }           transparent;    /* The transparent color, if set. */
+   int         npalette;       /* Number of entries in the palette. */
+   store_palette
+               palette;
+} standard_display;
+
+static void
+standard_display_init(standard_display *dp, png_store* ps, png_uint_32 id,
+   int do_interlace, int use_update_info)
+{
+   memset(dp, 0, sizeof *dp);
+
+   dp->ps = ps;
+   dp->colour_type = COL_FROM_ID(id);
+   dp->bit_depth = DEPTH_FROM_ID(id);
+   if (dp->bit_depth < 1 || dp->bit_depth > 16)
+      internal_error(ps, "internal: bad bit depth");
+   if (dp->colour_type == 3)
+      dp->red_sBIT = dp->blue_sBIT = dp->green_sBIT = dp->alpha_sBIT = 8;
+   else
+      dp->red_sBIT = dp->blue_sBIT = dp->green_sBIT = dp->alpha_sBIT =
+         dp->bit_depth;
+   dp->interlace_type = INTERLACE_FROM_ID(id);
+   dp->id = id;
+   /* All the rest are filled in after the read_info: */
+   dp->w = 0;
+   dp->h = 0;
+   dp->npasses = 0;
+   dp->pixel_size = 0;
+   dp->bit_width = 0;
+   dp->cbRow = 0;
+   dp->do_interlace = do_interlace;
+   dp->is_transparent = 0;
+   dp->speed = ps->speed;
+   dp->use_update_info = use_update_info;
+   dp->npalette = 0;
+   /* Preset the transparent color to black: */
+   memset(&dp->transparent, 0, sizeof dp->transparent);
+   /* Preset the palette to full intensity/opaque througout: */
+   memset(dp->palette, 0xff, sizeof dp->palette);
+}
+
+/* Initialize the palette fields - this must be done later because the palette
+ * comes from the particular png_store_file that is selected.
+ */
+static void
+standard_palette_init(standard_display *dp)
+{
+   store_palette_entry *palette = store_current_palette(dp->ps, &dp->npalette);
+
+   /* The remaining entries remain white/opaque. */
+   if (dp->npalette > 0)
+   {
+      int i = dp->npalette;
+      memcpy(dp->palette, palette, i * sizeof *palette);
+
+      /* Check for a non-opaque palette entry: */
+      while (--i >= 0)
+         if (palette[i].alpha < 255)
+            break;
+
+#     ifdef __GNUC__
+         /* GCC can't handle the more obviously optimizable version. */
+         if (i >= 0)
+            dp->is_transparent = 1;
+         else
+            dp->is_transparent = 0;
+#     else
+         dp->is_transparent = (i >= 0);
+#     endif
+   }
+}
+
+/* Utility to read the palette from the PNG file and convert it into
+ * store_palette format.  This returns 1 if there is any transparency in the
+ * palette (it does not check for a transparent colour in the non-palette case.)
+ */
+static int
+read_palette(store_palette palette, int *npalette, png_structp pp, png_infop pi)
+{
+   png_colorp pal;
+   png_bytep trans_alpha;
+   int num;
+
+   pal = 0;
+   *npalette = -1;
+
+   if (png_get_PLTE(pp, pi, &pal, npalette) & PNG_INFO_PLTE)
+   {
+      int i = *npalette;
+
+      if (i <= 0 || i > 256)
+         png_error(pp, "validate: invalid PLTE count");
+
+      while (--i >= 0)
+      {
+         palette[i].red = pal[i].red;
+         palette[i].green = pal[i].green;
+         palette[i].blue = pal[i].blue;
+      }
+
+      /* Mark the remainder of the entries with a flag value (other than
+       * white/opaque which is the flag value stored above.)
+       */
+      memset(palette + *npalette, 126, (256-*npalette) * sizeof *palette);
+   }
+
+   else /* !png_get_PLTE */
+   {
+      if (*npalette != (-1))
+         png_error(pp, "validate: invalid PLTE result");
+      /* But there is no palette, so record this: */
+      *npalette = 0;
+      memset(palette, 113, sizeof (store_palette));
+   }
+
+   trans_alpha = 0;
+   num = 2; /* force error below */
+   if ((png_get_tRNS(pp, pi, &trans_alpha, &num, 0) & PNG_INFO_tRNS) != 0 &&
+      (trans_alpha != NULL || num != 1/*returns 1 for a transparent color*/) &&
+      /* Oops, if a palette tRNS gets expanded png_read_update_info (at least so
+       * far as 1.5.4) does not remove the trans_alpha pointer, only num_trans,
+       * so in the above call we get a success, we get a pointer (who knows what
+       * to) and we get num_trans == 0:
+       */
+      !(trans_alpha != NULL && num == 0)) /* TODO: fix this in libpng. */
+   {
+      int i;
+
+      /* Any of these are crash-worthy - given the implementation of
+       * png_get_tRNS up to 1.5 an app won't crash if it just checks the
+       * result above and fails to check that the variables it passed have
+       * actually been filled in!  Note that if the app were to pass the
+       * last, png_color_16p, variable too it couldn't rely on this.
+       */
+      if (trans_alpha == NULL || num <= 0 || num > 256 || num > *npalette)
+         png_error(pp, "validate: unexpected png_get_tRNS (palette) result");
+
+      for (i=0; i<num; ++i)
+         palette[i].alpha = trans_alpha[i];
+
+      for (num=*npalette; i<num; ++i)
+         palette[i].alpha = 255;
+
+      for (; i<256; ++i)
+         palette[i].alpha = 33; /* flag value */
+
+      return 1; /* transparency */
+   }
+
+   else
+   {
+      /* No palette transparency - just set the alpha channel to opaque. */
+      int i;
+
+      for (i=0, num=*npalette; i<num; ++i)
+         palette[i].alpha = 255;
+
+      for (; i<256; ++i)
+         palette[i].alpha = 55; /* flag value */
+
+      return 0; /* no transparency */
+   }
+}
+
+/* Utility to validate the palette if it should not have changed (the
+ * non-transform case).
+ */
+static void
+standard_palette_validate(standard_display *dp, png_structp pp, png_infop pi)
+{
+   int npalette;
+   store_palette palette;
+
+   if (read_palette(palette, &npalette, pp, pi) != dp->is_transparent)
+      png_error(pp, "validate: palette transparency changed");
+
+   if (npalette != dp->npalette)
+   {
+      size_t pos = 0;
+      char msg[64];
+
+      pos = safecat(msg, sizeof msg, pos, "validate: palette size changed: ");
+      pos = safecatn(msg, sizeof msg, pos, dp->npalette);
+      pos = safecat(msg, sizeof msg, pos, " -> ");
+      pos = safecatn(msg, sizeof msg, pos, npalette);
+      png_error(pp, msg);
+   }
+
+   {
+      int i = npalette; /* npalette is aliased */
+
+      while (--i >= 0)
+         if (palette[i].red != dp->palette[i].red ||
+            palette[i].green != dp->palette[i].green ||
+            palette[i].blue != dp->palette[i].blue ||
+            palette[i].alpha != dp->palette[i].alpha)
+            png_error(pp, "validate: PLTE or tRNS chunk changed");
+   }
+}
+
+/* By passing a 'standard_display' the progressive callbacks can be used
+ * directly by the sequential code, the functions suffixed "_imp" are the
+ * implementations, the functions without the suffix are the callbacks.
+ *
+ * The code for the info callback is split into two because this callback calls
+ * png_read_update_info or png_start_read_image and what gets called depends on
+ * whether the info needs updating (we want to test both calls in pngvalid.)
+ */
+static void
+standard_info_part1(standard_display *dp, png_structp pp, png_infop pi)
+{
+   if (png_get_bit_depth(pp, pi) != dp->bit_depth)
+      png_error(pp, "validate: bit depth changed");
+
+   if (png_get_color_type(pp, pi) != dp->colour_type)
+      png_error(pp, "validate: color type changed");
+
+   if (png_get_filter_type(pp, pi) != PNG_FILTER_TYPE_BASE)
+      png_error(pp, "validate: filter type changed");
+
+   if (png_get_interlace_type(pp, pi) != dp->interlace_type)
+      png_error(pp, "validate: interlacing changed");
+
+   if (png_get_compression_type(pp, pi) != PNG_COMPRESSION_TYPE_BASE)
+      png_error(pp, "validate: compression type changed");
+
+   dp->w = png_get_image_width(pp, pi);
+
+   if (dp->w != standard_width(pp, dp->id))
+      png_error(pp, "validate: image width changed");
+
+   dp->h = png_get_image_height(pp, pi);
+
+   if (dp->h != standard_height(pp, dp->id))
+      png_error(pp, "validate: image height changed");
+
+   /* Record (but don't check at present) the input sBIT according to the colour
+    * type information.
+    */
+   {
+      png_color_8p sBIT = 0;
+
+      if (png_get_sBIT(pp, pi, &sBIT) & PNG_INFO_sBIT)
+      {
+         int sBIT_invalid = 0;
+
+         if (sBIT == 0)
+            png_error(pp, "validate: unexpected png_get_sBIT result");
+
+         if (dp->colour_type & PNG_COLOR_MASK_COLOR)
+         {
+            if (sBIT->red == 0 || sBIT->red > dp->bit_depth)
+               sBIT_invalid = 1;
+            else
+               dp->red_sBIT = sBIT->red;
+
+            if (sBIT->green == 0 || sBIT->green > dp->bit_depth)
+               sBIT_invalid = 1;
+            else
+               dp->green_sBIT = sBIT->green;
+
+            if (sBIT->blue == 0 || sBIT->blue > dp->bit_depth)
+               sBIT_invalid = 1;
+            else
+               dp->blue_sBIT = sBIT->blue;
+         }
+
+         else /* !COLOR */
+         {
+            if (sBIT->gray == 0 || sBIT->gray > dp->bit_depth)
+               sBIT_invalid = 1;
+            else
+               dp->blue_sBIT = dp->green_sBIT = dp->red_sBIT = sBIT->gray;
+         }
+
+         /* All 8 bits in tRNS for a palette image are significant - see the
+          * spec.
+          */
+         if (dp->colour_type & PNG_COLOR_MASK_ALPHA)
+         {
+            if (sBIT->alpha == 0 || sBIT->alpha > dp->bit_depth)
+               sBIT_invalid = 1;
+            else
+               dp->alpha_sBIT = sBIT->alpha;
+         }
+
+         if (sBIT_invalid)
+            png_error(pp, "validate: sBIT value out of range");
+      }
+   }
+
+   /* Important: this is validating the value *before* any transforms have been
+    * put in place.  It doesn't matter for the standard tests, where there are
+    * no transforms, but it does for other tests where rowbytes may change after
+    * png_read_update_info.
+    */
+   if (png_get_rowbytes(pp, pi) != standard_rowsize(pp, dp->id))
+      png_error(pp, "validate: row size changed");
+
+   /* Validate the colour type 3 palette (this can be present on other color
+    * types.)
+    */
+   standard_palette_validate(dp, pp, pi);
+
+   /* In any case always check for a tranparent color (notice that the
+    * colour type 3 case must not give a successful return on the get_tRNS call
+    * with these arguments!)
+    */
+   {
+      png_color_16p trans_color = 0;
+
+      if (png_get_tRNS(pp, pi, 0, 0, &trans_color) & PNG_INFO_tRNS)
+      {
+         if (trans_color == 0)
+            png_error(pp, "validate: unexpected png_get_tRNS (color) result");
+
+         switch (dp->colour_type)
+         {
+         case 0:
+            dp->transparent.red = dp->transparent.green = dp->transparent.blue =
+               trans_color->gray;
+            dp->is_transparent = 1;
+            break;
+
+         case 2:
+            dp->transparent.red = trans_color->red;
+            dp->transparent.green = trans_color->green;
+            dp->transparent.blue = trans_color->blue;
+            dp->is_transparent = 1;
+            break;
+
+         case 3:
+            /* Not expected because it should result in the array case
+             * above.
+             */
+            png_error(pp, "validate: unexpected png_get_tRNS result");
+            break;
+
+         default:
+            png_error(pp, "validate: invalid tRNS chunk with alpha image");
+         }
+      }
+   }
+
+   /* Read the number of passes - expected to match the value used when
+    * creating the image (interlaced or not).  This has the side effect of
+    * turning on interlace handling (if do_interlace is not set.)
+    */
+   dp->npasses = npasses_from_interlace_type(pp, dp->interlace_type);
+   if (!dp->do_interlace && dp->npasses != png_set_interlace_handling(pp))
+      png_error(pp, "validate: file changed interlace type");
+
+   /* Caller calls png_read_update_info or png_start_read_image now, then calls
+    * part2.
+    */
+}
+
+/* This must be called *after* the png_read_update_info call to get the correct
+ * 'rowbytes' value, otherwise png_get_rowbytes will refer to the untransformed
+ * image.
+ */
+static void
+standard_info_part2(standard_display *dp, png_structp pp, png_infop pi,
+    int nImages)
+{
+   /* Record cbRow now that it can be found. */
+   dp->pixel_size = bit_size(pp, png_get_color_type(pp, pi),
+      png_get_bit_depth(pp, pi));
+   dp->bit_width = png_get_image_width(pp, pi) * dp->pixel_size;
+   dp->cbRow = png_get_rowbytes(pp, pi);
+
+   /* Validate the rowbytes here again. */
+   if (dp->cbRow != (dp->bit_width+7)/8)
+      png_error(pp, "bad png_get_rowbytes calculation");
+
+   /* Then ensure there is enough space for the output image(s). */
+   store_ensure_image(dp->ps, pp, nImages, dp->cbRow, dp->h);
+}
+
+static void
+standard_info_imp(standard_display *dp, png_structp pp, png_infop pi,
+    int nImages)
+{
+   /* Note that the validation routine has the side effect of turning on
+    * interlace handling in the subsequent code.
+    */
+   standard_info_part1(dp, pp, pi);
+
+   /* And the info callback has to call this (or png_read_update_info - see
+    * below in the png_modifier code for that variant.
+    */
+   if (dp->use_update_info)
+   {
+      /* For debugging the effect of multiple calls: */
+      int i = dp->use_update_info;
+      while (i-- > 0)
+         png_read_update_info(pp, pi);
+   }
+
+   else
+      png_start_read_image(pp);
+
+   /* Validate the height, width and rowbytes plus ensure that sufficient buffer
+    * exists for decoding the image.
+    */
+   standard_info_part2(dp, pp, pi, nImages);
+}
+
+static void
+standard_info(png_structp pp, png_infop pi)
+{
+   standard_display *dp = voidcast(standard_display*,
+      png_get_progressive_ptr(pp));
+
+   /* Call with nImages==1 because the progressive reader can only produce one
+    * image.
+    */
+   standard_info_imp(dp, pp, pi, 1 /*only one image*/);
+}
+
+static void
+progressive_row(png_structp pp, png_bytep new_row, png_uint_32 y, int pass)
+{
+   PNG_CONST standard_display *dp = voidcast(standard_display*,
+      png_get_progressive_ptr(pp));
+
+   /* When handling interlacing some rows will be absent in each pass, the
+    * callback still gets called, but with a NULL pointer.  This is checked
+    * in the 'else' clause below.  We need our own 'cbRow', but we can't call
+    * png_get_rowbytes because we got no info structure.
+    */
+   if (new_row != NULL)
+   {
+      png_bytep row;
+
+      /* In the case where the reader doesn't do the interlace it gives
+       * us the y in the sub-image:
+       */
+      if (dp->do_interlace && dp->interlace_type == PNG_INTERLACE_ADAM7)
+      {
+#ifdef PNG_USER_TRANSFORM_INFO_SUPPORTED
+         /* Use this opportunity to validate the png 'current' APIs: */
+         if (y != png_get_current_row_number(pp))
+            png_error(pp, "png_get_current_row_number is broken");
+
+         if (pass != png_get_current_pass_number(pp))
+            png_error(pp, "png_get_current_pass_number is broken");
+#endif
+
+         y = PNG_ROW_FROM_PASS_ROW(y, pass);
+      }
+
+      /* Validate this just in case. */
+      if (y >= dp->h)
+         png_error(pp, "invalid y to progressive row callback");
+
+      row = store_image_row(dp->ps, pp, 0, y);
+
+#ifdef PNG_READ_INTERLACING_SUPPORTED
+      /* Combine the new row into the old: */
+      if (dp->do_interlace)
+      {
+         if (dp->interlace_type == PNG_INTERLACE_ADAM7)
+            deinterlace_row(row, new_row, dp->pixel_size, dp->w, pass);
+         else
+            row_copy(row, new_row, dp->pixel_size * dp->w);
+      }
+      else
+         png_progressive_combine_row(pp, row, new_row);
+   } else if (dp->interlace_type == PNG_INTERLACE_ADAM7 &&
+      PNG_ROW_IN_INTERLACE_PASS(y, pass) &&
+      PNG_PASS_COLS(dp->w, pass) > 0)
+      png_error(pp, "missing row in progressive de-interlacing");
+#endif /* PNG_READ_INTERLACING_SUPPORTED */
+}
+
+static void
+sequential_row(standard_display *dp, png_structp pp, png_infop pi,
+    PNG_CONST int iImage, PNG_CONST int iDisplay)
+{
+   PNG_CONST int         npasses = dp->npasses;
+   PNG_CONST int         do_interlace = dp->do_interlace &&
+      dp->interlace_type == PNG_INTERLACE_ADAM7;
+   PNG_CONST png_uint_32 height = standard_height(pp, dp->id);
+   PNG_CONST png_uint_32 width = standard_width(pp, dp->id);
+   PNG_CONST png_store*  ps = dp->ps;
+   int pass;
+
+   for (pass=0; pass<npasses; ++pass)
+   {
+      png_uint_32 y;
+      png_uint_32 wPass = PNG_PASS_COLS(width, pass);
+
+      for (y=0; y<height; ++y)
+      {
+         if (do_interlace)
+         {
+            /* wPass may be zero or this row may not be in this pass.
+             * png_read_row must not be called in either case.
+             */
+            if (wPass > 0 && PNG_ROW_IN_INTERLACE_PASS(y, pass))
+            {
+               /* Read the row into a pair of temporary buffers, then do the
+                * merge here into the output rows.
+                */
+               png_byte row[STANDARD_ROWMAX], display[STANDARD_ROWMAX];
+
+               /* The following aids (to some extent) error detection - we can
+                * see where png_read_row wrote.  Use opposite values in row and
+                * display to make this easier.  Don't use 0xff (which is used in
+                * the image write code to fill unused bits) or 0 (which is a
+                * likely value to overwrite unused bits with).
+                */
+               memset(row, 0xc5, sizeof row);
+               memset(display, 0x5c, sizeof display);
+
+               png_read_row(pp, row, display);
+
+               if (iImage >= 0)
+                  deinterlace_row(store_image_row(ps, pp, iImage, y), row,
+                     dp->pixel_size, dp->w, pass);
+
+               if (iDisplay >= 0)
+                  deinterlace_row(store_image_row(ps, pp, iDisplay, y), display,
+                     dp->pixel_size, dp->w, pass);
+            }
+         }
+         else
+            png_read_row(pp,
+               iImage >= 0 ? store_image_row(ps, pp, iImage, y) : NULL,
+               iDisplay >= 0 ? store_image_row(ps, pp, iDisplay, y) : NULL);
+      }
+   }
+
+   /* And finish the read operation (only really necessary if the caller wants
+    * to find additional data in png_info from chunks after the last IDAT.)
+    */
+   png_read_end(pp, pi);
+}
+
+static void
+standard_row_validate(standard_display *dp, png_structp pp,
+   int iImage, int iDisplay, png_uint_32 y)
+{
+   int where;
+   png_byte std[STANDARD_ROWMAX];
+
+   /* The row must be pre-initialized to the magic number here for the size
+    * tests to pass:
+    */
+   memset(std, 178, sizeof std);
+   standard_row(pp, std, dp->id, y);
+
+   /* At the end both the 'row' and 'display' arrays should end up identical.
+    * In earlier passes 'row' will be partially filled in, with only the pixels
+    * that have been read so far, but 'display' will have those pixels
+    * replicated to fill the unread pixels while reading an interlaced image.
+#if PNG_LIBPNG_VER < 10506
+    * The side effect inside the libpng sequential reader is that the 'row'
+    * array retains the correct values for unwritten pixels within the row
+    * bytes, while the 'display' array gets bits off the end of the image (in
+    * the last byte) trashed.  Unfortunately in the progressive reader the
+    * row bytes are always trashed, so we always do a pixel_cmp here even though
+    * a memcmp of all cbRow bytes will succeed for the sequential reader.
+#endif
+    */
+   if (iImage >= 0 &&
+      (where = pixel_cmp(std, store_image_row(dp->ps, pp, iImage, y),
+            dp->bit_width)) != 0)
+   {
+      char msg[64];
+      sprintf(msg, "PNG image row[%d][%d] changed from %.2x to %.2x", y,
+         where-1, std[where-1],
+         store_image_row(dp->ps, pp, iImage, y)[where-1]);
+      png_error(pp, msg);
+   }
+
+#if PNG_LIBPNG_VER < 10506
+   /* In this case use pixel_cmp because we need to compare a partial
+    * byte at the end of the row if the row is not an exact multiple
+    * of 8 bits wide.  (This is fixed in libpng-1.5.6 and pixel_cmp is
+    * changed to match!)
+    */
+#endif
+   if (iDisplay >= 0 &&
+      (where = pixel_cmp(std, store_image_row(dp->ps, pp, iDisplay, y),
+         dp->bit_width)) != 0)
+   {
+      char msg[64];
+      sprintf(msg, "display  row[%d][%d] changed from %.2x to %.2x", y,
+         where-1, std[where-1],
+         store_image_row(dp->ps, pp, iDisplay, y)[where-1]);
+      png_error(pp, msg);
+   }
+}
+
+static void
+standard_image_validate(standard_display *dp, png_structp pp, int iImage,
+    int iDisplay)
+{
+   png_uint_32 y;
+
+   if (iImage >= 0)
+      store_image_check(dp->ps, pp, iImage);
+
+   if (iDisplay >= 0)
+      store_image_check(dp->ps, pp, iDisplay);
+
+   for (y=0; y<dp->h; ++y)
+      standard_row_validate(dp, pp, iImage, iDisplay, y);
+
+   /* This avoids false positives if the validation code is never called! */
+   dp->ps->validated = 1;
+}
+
+static void
+standard_end(png_structp pp, png_infop pi)
+{
+   standard_display *dp = voidcast(standard_display*,
+      png_get_progressive_ptr(pp));
+
+   UNUSED(pi)
+
+   /* Validate the image - progressive reading only produces one variant for
+    * interlaced images.
+    */
+   standard_image_validate(dp, pp, 0, -1);
+}
+
+/* A single test run checking the standard image to ensure it is not damaged. */
+static void
+standard_test(png_store* PNG_CONST psIn, png_uint_32 PNG_CONST id,
+   int do_interlace, int use_update_info)
+{
+   standard_display d;
+   context(psIn, fault);
+
+   /* Set up the display (stack frame) variables from the arguments to the
+    * function and initialize the locals that are filled in later.
+    */
+   standard_display_init(&d, psIn, id, do_interlace, use_update_info);
+
+   /* Everything is protected by a Try/Catch.  The functions called also
+    * typically have local Try/Catch blocks.
+    */
+   Try
+   {
+      png_structp pp;
+      png_infop pi;
+
+      /* Get a png_struct for reading the image. This will throw an error if it
+       * fails, so we don't need to check the result.
+       */
+      pp = set_store_for_read(d.ps, &pi, d.id,
+         d.do_interlace ?  (d.ps->progressive ?
+            "pngvalid progressive deinterlacer" :
+            "pngvalid sequential deinterlacer") : (d.ps->progressive ?
+               "progressive reader" : "sequential reader"));
+
+      /* Initialize the palette correctly from the png_store_file. */
+      standard_palette_init(&d);
+
+      /* Introduce the correct read function. */
+      if (d.ps->progressive)
+      {
+         png_set_progressive_read_fn(pp, &d, standard_info, progressive_row,
+            standard_end);
+
+         /* Now feed data into the reader until we reach the end: */
+         store_progressive_read(d.ps, pp, pi);
+      }
+      else
+      {
+         /* Note that this takes the store, not the display. */
+         png_set_read_fn(pp, d.ps, store_read);
+
+         /* Check the header values: */
+         png_read_info(pp, pi);
+
+         /* The code tests both versions of the images that the sequential
+          * reader can produce.
+          */
+         standard_info_imp(&d, pp, pi, 2 /*images*/);
+
+         /* Need the total bytes in the image below; we can't get to this point
+          * unless the PNG file values have been checked against the expected
+          * values.
+          */
+         {
+            sequential_row(&d, pp, pi, 0, 1);
+
+            /* After the last pass loop over the rows again to check that the
+             * image is correct.
+             */
+            if (!d.speed)
+               standard_image_validate(&d, pp, 0, 1);
+            else
+               d.ps->validated = 1;
+         }
+      }
+
+      /* Check for validation. */
+      if (!d.ps->validated)
+         png_error(pp, "image read failed silently");
+
+      /* Successful completion. */
+   }
+
+   Catch(fault)
+      d.ps = fault; /* make sure this hasn't been clobbered. */
+
+   /* In either case clean up the store. */
+   store_read_reset(d.ps);
+}
+
+static int
+test_standard(png_modifier* PNG_CONST pm, png_byte PNG_CONST colour_type,
+    int bdlo, int PNG_CONST bdhi)
+{
+   for (; bdlo <= bdhi; ++bdlo)
+   {
+      int interlace_type;
+
+      for (interlace_type = PNG_INTERLACE_NONE;
+           interlace_type < PNG_INTERLACE_LAST; ++interlace_type)
+      {
+         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,
+            interlace_type, 0, 0, 0), 0/*do_interlace*/, pm->use_update_info);
+
+         if (fail(pm))
+            return 0;
+      }
+   }
+
+   return 1; /* keep going */
+}
+
+static void
+perform_standard_test(png_modifier *pm)
+{
+   /* Test each colour type over the valid range of bit depths (expressed as
+    * log2(bit_depth) in turn, stop as soon as any error is detected.
+    */
+   if (!test_standard(pm, 0, 0, READ_BDHI))
+      return;
+
+   if (!test_standard(pm, 2, 3, READ_BDHI))
+      return;
+
+   if (!test_standard(pm, 3, 0, 3))
+      return;
+
+   if (!test_standard(pm, 4, 3, READ_BDHI))
+      return;
+
+   if (!test_standard(pm, 6, 3, READ_BDHI))
+      return;
+}
+
+
+/********************************** SIZE TESTS ********************************/
+static int
+test_size(png_modifier* PNG_CONST pm, png_byte PNG_CONST colour_type,
+    int bdlo, int PNG_CONST bdhi)
+{
+   /* Run the tests on each combination.
+    *
+    * NOTE: on my 32 bit x86 each of the following blocks takes
+    * a total of 3.5 seconds if done across every combo of bit depth
+    * width and height.  This is a waste of time in practice, hence the
+    * hinc and winc stuff:
+    */
+   static PNG_CONST png_byte hinc[] = {1, 3, 11, 1, 5};
+   static PNG_CONST png_byte winc[] = {1, 9, 5, 7, 1};
+   for (; bdlo <= bdhi; ++bdlo)
+   {
+      png_uint_32 h, w;
+
+      for (h=1; h<=16; h+=hinc[bdlo]) for (w=1; w<=16; w+=winc[bdlo])
+      {
+         /* First test all the 'size' images against the sequential
+          * reader using libpng to deinterlace (where required.)  This
+          * validates the write side of libpng.  There are four possibilities
+          * to validate.
+          */
+         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,
+            PNG_INTERLACE_NONE, w, h, 0), 0/*do_interlace*/,
+            pm->use_update_info);
+
+         if (fail(pm))
+            return 0;
+
+         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,
+            PNG_INTERLACE_NONE, w, h, 1), 0/*do_interlace*/,
+            pm->use_update_info);
+
+         if (fail(pm))
+            return 0;
+
+         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,
+            PNG_INTERLACE_ADAM7, w, h, 0), 0/*do_interlace*/,
+            pm->use_update_info);
+
+         if (fail(pm))
+            return 0;
+
+         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,
+            PNG_INTERLACE_ADAM7, w, h, 1), 0/*do_interlace*/,
+            pm->use_update_info);
+
+         if (fail(pm))
+            return 0;
+
+         /* Now validate the interlaced read side - do_interlace true,
+          * in the progressive case this does actually make a difference
+          * to the code used in the non-interlaced case too.
+          */
+         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,
+            PNG_INTERLACE_NONE, w, h, 0), 1/*do_interlace*/,
+            pm->use_update_info);
+
+         if (fail(pm))
+            return 0;
+
+         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,
+            PNG_INTERLACE_ADAM7, w, h, 0), 1/*do_interlace*/,
+            pm->use_update_info);
+
+         if (fail(pm))
+            return 0;
+      }
+   }
+
+   return 1; /* keep going */
+}
+
+static void
+perform_size_test(png_modifier *pm)
+{
+   /* Test each colour type over the valid range of bit depths (expressed as
+    * log2(bit_depth) in turn, stop as soon as any error is detected.
+    */
+   if (!test_size(pm, 0, 0, READ_BDHI))
+      return;
+
+   if (!test_size(pm, 2, 3, READ_BDHI))
+      return;
+
+   /* For the moment don't do the palette test - it's a waste of time when
+    * compared to the grayscale test.
+    */
+#if 0
+   if (!test_size(pm, 3, 0, 3))
+      return;
+#endif
+
+   if (!test_size(pm, 4, 3, READ_BDHI))
+      return;
+
+   if (!test_size(pm, 6, 3, READ_BDHI))
+      return;
+}
+
+
+/******************************* TRANSFORM TESTS ******************************/
+#ifdef PNG_READ_TRANSFORMS_SUPPORTED
+/* A set of tests to validate libpng image transforms.  The possibilities here
+ * are legion because the transforms can be combined in a combinatorial
+ * fashion.  To deal with this some measure of restraint is required, otherwise
+ * the tests would take forever.
+ */
+typedef struct image_pixel
+{
+   /* A local (pngvalid) representation of a PNG pixel, in all its
+    * various forms.
+    */
+   unsigned int red, green, blue, alpha; /* For non-palette images. */
+   unsigned int palette_index;           /* For a palette image. */
+   png_byte colour_type;                 /* As in the spec. */
+   png_byte bit_depth;                   /* Defines bit size in row */
+   png_byte sample_depth;                /* Scale of samples */
+   int      have_tRNS;                   /* tRNS chunk may need processing */
+
+   /* For checking the code calculates double precision floating point values
+    * along with an error value, accumulated from the transforms.  Because an
+    * sBIT setting allows larger error bounds (indeed, by the spec, apparently
+    * up to just less than +/-1 in the scaled value) the *lowest* sBIT for each
+    * channel is stored.  This sBIT value is folded in to the stored error value
+    * at the end of the application of the transforms to the pixel.
+    */
+   double   redf, greenf, bluef, alphaf;
+   double   rede, greene, bluee, alphae;
+   png_byte red_sBIT, green_sBIT, blue_sBIT, alpha_sBIT;
+} image_pixel;
+
+/* Shared utility function, see below. */
+static void
+image_pixel_setf(image_pixel *this, unsigned int max)
+{
+   this->redf = this->red / (double)max;
+   this->greenf = this->green / (double)max;
+   this->bluef = this->blue / (double)max;
+   this->alphaf = this->alpha / (double)max;
+
+   if (this->red < max)
+      this->rede = this->redf * DBL_EPSILON;
+   else
+      this->rede = 0;
+   if (this->green < max)
+      this->greene = this->greenf * DBL_EPSILON;
+   else
+      this->greene = 0;
+   if (this->blue < max)
+      this->bluee = this->bluef * DBL_EPSILON;
+   else
+      this->bluee = 0;
+   if (this->alpha < max)
+      this->alphae = this->alphaf * DBL_EPSILON;
+   else
+      this->alphae = 0;
+}
+
+/* Initialize the structure for the next pixel - call this before doing any
+ * transforms and call it for each pixel since all the fields may need to be
+ * reset.
+ */
+static void
+image_pixel_init(image_pixel *this, png_const_bytep row, png_byte colour_type,
+    png_byte bit_depth, png_uint_32 x, store_palette palette)
+{
+   PNG_CONST png_byte sample_depth = (png_byte)(colour_type ==
+      PNG_COLOR_TYPE_PALETTE ? 8 : bit_depth);
+   PNG_CONST unsigned int max = (1U<<sample_depth)-1;
+
+   /* Initially just set everything to the same number and the alpha to opaque.
+    * Note that this currently assumes a simple palette where entry x has colour
+    * rgb(x,x,x)!
+    */
+   this->palette_index = this->red = this->green = this->blue =
+      sample(row, colour_type, bit_depth, x, 0);
+   this->alpha = max;
+   this->red_sBIT = this->green_sBIT = this->blue_sBIT = this->alpha_sBIT =
+      sample_depth;
+
+   /* Then override as appropriate: */
+   if (colour_type == 3) /* palette */
+   {
+      /* This permits the caller to default to the sample value. */
+      if (palette != 0)
+      {
+         PNG_CONST unsigned int i = this->palette_index;
+
+         this->red = palette[i].red;
+         this->green = palette[i].green;
+         this->blue = palette[i].blue;
+         this->alpha = palette[i].alpha;
+      }
+   }
+
+   else /* not palette */
+   {
+      unsigned int i = 0;
+
+      if (colour_type & 2)
+      {
+         this->green = sample(row, colour_type, bit_depth, x, 1);
+         this->blue = sample(row, colour_type, bit_depth, x, 2);
+         i = 2;
+      }
+      if (colour_type & 4)
+         this->alpha = sample(row, colour_type, bit_depth, x, ++i);
+   }
+
+   /* Calculate the scaled values, these are simply the values divided by
+    * 'max' and the error is initialized to the double precision epsilon value
+    * from the header file.
+    */
+   image_pixel_setf(this, max);
+
+   /* Store the input information for use in the transforms - these will
+    * modify the information.
+    */
+   this->colour_type = colour_type;
+   this->bit_depth = bit_depth;
+   this->sample_depth = sample_depth;
+   this->have_tRNS = 0;
+}
+
+/* Convert a palette image to an rgb image.  This necessarily converts the tRNS
+ * chunk at the same time, because the tRNS will be in palette form.  The way
+ * palette validation works means that the original palette is never updated,
+ * instead the image_pixel value from the row contains the RGB of the
+ * corresponding palette entry and *this* is updated.  Consequently this routine
+ * only needs to change the colour type information.
+ */
+static void
+image_pixel_convert_PLTE(image_pixel *this)
+{
+   if (this->colour_type == PNG_COLOR_TYPE_PALETTE)
+   {
+      if (this->have_tRNS)
+      {
+         this->colour_type = PNG_COLOR_TYPE_RGB_ALPHA;
+         this->have_tRNS = 0;
+      }
+      else
+         this->colour_type = PNG_COLOR_TYPE_RGB;
+
+      /* The bit depth of the row changes at this point too (notice that this is
+       * the row format, not the sample depth, which is separate.)
+       */
+      this->bit_depth = 8;
+   }
+}
+
+/* Add an alpha channel; this will import the tRNS information because tRNS is
+ * not valid in an alpha image.  The bit depth will invariably be set to at
+ * least 8.  Palette images will be converted to alpha (using the above API).
+ */
+static void
+image_pixel_add_alpha(image_pixel *this, PNG_CONST standard_display *display)
+{
+   if (this->colour_type == PNG_COLOR_TYPE_PALETTE)
+      image_pixel_convert_PLTE(this);
+
+   if ((this->colour_type & PNG_COLOR_MASK_ALPHA) == 0)
+   {
+      if (this->colour_type == PNG_COLOR_TYPE_GRAY)
+      {
+         if (this->bit_depth < 8)
+            this->bit_depth = 8;
+
+         if (this->have_tRNS)
+         {
+            this->have_tRNS = 0;
+
+            /* Check the input, original, channel value here against the
+             * original tRNS gray chunk valie.
+             */
+            if (this->red == display->transparent.red)
+               this->alphaf = 0;
+            else
+               this->alphaf = 1;
+         }
+         else
+            this->alphaf = 1;
+
+         this->colour_type = PNG_COLOR_TYPE_GRAY_ALPHA;
+      }
+
+      else if (this->colour_type == PNG_COLOR_TYPE_RGB)
+      {
+         if (this->have_tRNS)
+         {
+            this->have_tRNS = 0;
+
+            /* Again, check the exact input values, not the current transformed
+             * value!
+             */
+            if (this->red == display->transparent.red &&
+               this->green == display->transparent.green &&
+               this->blue == display->transparent.blue)
+               this->alphaf = 0;
+            else
+               this->alphaf = 1;
+
+            this->colour_type = PNG_COLOR_TYPE_RGB_ALPHA;
+         }
+      }
+
+      /* The error in the alpha is zero and the sBIT value comes from the
+       * original sBIT data (actually it will always be the original bit depth).
+       */
+      this->alphae = 0;
+      this->alpha_sBIT = display->alpha_sBIT;
+   }
+}
+
+struct transform_display;
+typedef struct image_transform
+{
+   /* The name of this transform: a string. */
+   PNG_CONST char *name;
+
+   /* Each transform can be disabled from the command line: */
+   int enable;
+
+   /* The global list of transforms; read only. */
+   struct image_transform *PNG_CONST list;
+
+   /* The global count of the number of times this transform has been set on an
+    * image.
+    */
+   unsigned int global_use;
+
+   /* The local count of the number of times this transform has been set. */
+   unsigned int local_use;
+
+   /* The next transform in the list, each transform must call its own next
+    * transform after it has processed the pixel successfully.
+    */
+   PNG_CONST struct image_transform *next;
+
+   /* A single transform for the image, expressed as a series of function
+    * callbacks and some space for values.
+    *
+    * First a callback to add any required modifications to the png_modifier;
+    * this gets called just before the modifier is set up for read.
+    */
+   void (*ini)(PNG_CONST struct image_transform *this,
+      struct transform_display *that);
+
+   /* And a callback to set the transform on the current png_read_struct:
+    */
+   void (*set)(PNG_CONST struct image_transform *this,
+      struct transform_display *that, png_structp pp, png_infop pi);
+
+   /* Then a transform that takes an input pixel in one PNG format or another
+    * and modifies it by a pngvalid implementation of the transform (thus
+    * duplicating the libpng intent without, we hope, duplicating the bugs
+    * in the libpng implementation!)  The png_structp is solely to allow error
+    * reporting via png_error and png_warning.
+    */
+   void (*mod)(PNG_CONST struct image_transform *this, image_pixel *that,
+      png_structp pp, PNG_CONST struct transform_display *display);
+
+   /* Add this transform to the list and return true if the transform is
+    * meaningful for this colour type and bit depth - if false then the
+    * transform should have no effect on the image so there's not a lot of
+    * point running it.
+    */
+   int (*add)(struct image_transform *this,
+      PNG_CONST struct image_transform **that, png_byte colour_type,
+      png_byte bit_depth);
+} image_transform;
+
+typedef struct transform_display
+{
+   standard_display this;
+
+   /* Parameters */
+   png_modifier*              pm;
+   PNG_CONST image_transform* transform_list;
+
+   /* Local variables */
+   png_byte output_colour_type;
+   png_byte output_bit_depth;
+
+   /* Modifications (not necessarily used.) */
+   gama_modification gama_mod;
+   chrm_modification chrm_mod;
+   srgb_modification srgb_mod;
+} transform_display;
+
+/* Set sRGB, cHRM and gAMA transforms as required by the current encoding. */
+static void
+transform_set_encoding(transform_display *this)
+{
+   /* Set up the png_modifier '_current' fields then use these to determine how
+    * to add appropriate chunks.
+    */
+   png_modifier *pm = this->pm;
+
+   modifier_set_encoding(pm);
+
+   if (modifier_color_encoding_is_set(pm))
+   {
+      if (modifier_color_encoding_is_sRGB(pm))
+         srgb_modification_init(&this->srgb_mod, pm, PNG_sRGB_INTENT_ABSOLUTE);
+
+      else
+      {
+         /* Set gAMA and cHRM separately. */
+         gama_modification_init(&this->gama_mod, pm, pm->current_gamma);
+
+         if (pm->current_encoding != 0)
+            chrm_modification_init(&this->chrm_mod, pm, pm->current_encoding);
+      }
+   }
+}
+
+/* Three functions to end the list: */
+static void
+image_transform_ini_end(PNG_CONST image_transform *this,
+   transform_display *that)
+{
+   UNUSED(this)
+   UNUSED(that)
+}
+
+static void
+image_transform_set_end(PNG_CONST image_transform *this,
+   transform_display *that, png_structp pp, png_infop pi)
+{
+   UNUSED(this)
+   UNUSED(that)
+   UNUSED(pp)
+   UNUSED(pi)
+}
+
+/* At the end of the list recalculate the output image pixel value from the
+ * double precision values set up by the preceding 'mod' calls:
+ */
+static unsigned int
+sample_scale(double sample_value, unsigned int scale)
+{
+   sample_value = floor(sample_value * scale + .5);
+
+   /* Return NaN as 0: */
+   if (!(sample_value > 0))
+      sample_value = 0;
+   else if (sample_value > scale)
+      sample_value = scale;
+
+   return (unsigned int)sample_value;
+}
+
+static void
+image_transform_mod_end(PNG_CONST image_transform *this, image_pixel *that,
+    png_structp pp, PNG_CONST transform_display *display)
+{
+   PNG_CONST unsigned int scale = (1U<<that->sample_depth)-1;
+
+   UNUSED(this)
+   UNUSED(pp)
+   UNUSED(display)
+
+   /* At the end recalculate the digitized red green and blue values according
+    * to the current sample_depth of the pixel.
+    *
+    * The sample value is simply scaled to the maximum, checking for over
+    * and underflow (which can both happen for some image transforms,
+    * including simple size scaling, though libpng doesn't do that at present.
+    */
+   that->red = sample_scale(that->redf, scale);
+
+   /* The error value is increased, at the end, according to the lowest sBIT
+    * value seen.  Common sense tells us that the intermediate integer
+    * representations are no more accurate than +/- 0.5 in the integral values,
+    * the sBIT allows the implementation to be worse than this.  In addition the
+    * PNG specification actually permits any error within the range (-1..+1),
+    * but that is ignored here.  Instead the final digitized value is compared,
+    * below to the digitized value of the error limits - this has the net effect
+    * of allowing (almost) +/-1 in the output value.  It's difficult to see how
+    * any algorithm that digitizes intermediate results can be more accurate.
+    */
+   that->rede += 1./(2*((1U<<that->red_sBIT)-1));
+
+   if (that->colour_type & PNG_COLOR_MASK_COLOR)
+   {
+      that->green = sample_scale(that->greenf, scale);
+      that->blue = sample_scale(that->bluef, scale);
+      that->greene += 1./(2*((1U<<that->green_sBIT)-1));
+      that->bluee += 1./(2*((1U<<that->blue_sBIT)-1));
+   }
+   else
+   {
+      that->blue = that->green = that->red;
+      that->bluef = that->greenf = that->redf;
+      that->bluee = that->greene = that->rede;
+   }
+
+   if ((that->colour_type & PNG_COLOR_MASK_ALPHA) ||
+      that->colour_type == PNG_COLOR_TYPE_PALETTE)
+   {
+      that->alpha = sample_scale(that->alphaf, scale);
+      that->alphae += 1./(2*((1U<<that->alpha_sBIT)-1));
+   }
+   else
+   {
+      that->alpha = scale; /* opaque */
+      that->alpha = 1;     /* Override this. */
+      that->alphae = 0;    /* It's exact ;-) */
+   }
+}
+
+/* Static 'end' structure: */
+static image_transform image_transform_end =
+{
+   "(end)", /* name */
+   1, /* enable */
+   0, /* list */
+   0, /* global_use */
+   0, /* local_use */
+   0, /* next */
+   image_transform_ini_end,
+   image_transform_set_end,
+   image_transform_mod_end,
+   0 /* never called, I want it to crash if it is! */
+};
+
+/* Reader callbacks and implementations, where they differ from the standard
+ * ones.
+ */
+static void
+transform_display_init(transform_display *dp, png_modifier *pm, png_uint_32 id,
+    PNG_CONST image_transform *transform_list)
+{
+   memset(dp, 0, sizeof *dp);
+
+   /* Standard fields */
+   standard_display_init(&dp->this, &pm->this, id, 0/*do_interlace*/,
+      pm->use_update_info);
+
+   /* Parameter fields */
+   dp->pm = pm;
+   dp->transform_list = transform_list;
+
+   /* Local variable fields */
+   dp->output_colour_type = 255; /* invalid */
+   dp->output_bit_depth = 255;  /* invalid */
+}
+
+static void
+transform_info_imp(transform_display *dp, png_structp pp, png_infop pi)
+{
+   /* Reuse the standard stuff as appropriate. */
+   standard_info_part1(&dp->this, pp, pi);
+
+   /* Now set the list of transforms. */
+   dp->transform_list->set(dp->transform_list, dp, pp, pi);
+
+   /* Update the info structure for these transforms: */
+   {
+      int i = dp->this.use_update_info;
+      /* Always do one call, even if use_update_info is 0. */
+      do
+         png_read_update_info(pp, pi);
+      while (--i > 0);
+   }
+
+   /* And get the output information into the standard_display */
+   standard_info_part2(&dp->this, pp, pi, 1/*images*/);
+
+   /* Plus the extra stuff we need for the transform tests: */
+   dp->output_colour_type = png_get_color_type(pp, pi);
+   dp->output_bit_depth = png_get_bit_depth(pp, pi);
+
+   /* Validate the combination of colour type and bit depth that we are getting
+    * out of libpng; the semantics of something not in the PNG spec are, at
+    * best, unclear.
+    */
+   switch (dp->output_colour_type)
+   {
+   case PNG_COLOR_TYPE_PALETTE:
+      if (dp->output_bit_depth > 8) goto error;
+      /*FALL THROUGH*/
+   case PNG_COLOR_TYPE_GRAY:
+      if (dp->output_bit_depth == 1 || dp->output_bit_depth == 2 ||
+         dp->output_bit_depth == 4)
+         break;
+      /*FALL THROUGH*/
+   default:
+      if (dp->output_bit_depth == 8 || dp->output_bit_depth == 16)
+         break;
+      /*FALL THROUGH*/
+   error:
+      {
+         char message[128];
+         size_t pos;
+
+         pos = safecat(message, sizeof message, 0,
+            "invalid final bit depth: colour type(");
+         pos = safecatn(message, sizeof message, pos, dp->output_colour_type);
+         pos = safecat(message, sizeof message, pos, ") with bit depth: ");
+         pos = safecatn(message, sizeof message, pos, dp->output_bit_depth);
+
+         png_error(pp, message);
+      }
+   }
+
+   /* Use a test pixel to check that the output agrees with what we expect -
+    * this avoids running the whole test if the output is unexpected.
+    */
+   {
+      image_pixel test_pixel;
+
+      memset(&test_pixel, 0, sizeof test_pixel);
+      test_pixel.colour_type = dp->this.colour_type; /* input */
+      test_pixel.bit_depth = dp->this.bit_depth;
+      if (test_pixel.colour_type == PNG_COLOR_TYPE_PALETTE)
+         test_pixel.sample_depth = 8;
+      else
+         test_pixel.sample_depth = test_pixel.bit_depth;
+      /* Don't need sBIT here, but it must be set to non-zero to avoid
+       * arithmetic overflows.
+       */
+      test_pixel.have_tRNS = dp->this.is_transparent;
+      test_pixel.red_sBIT = test_pixel.green_sBIT = test_pixel.blue_sBIT =
+         test_pixel.alpha_sBIT = test_pixel.sample_depth;
+
+      dp->transform_list->mod(dp->transform_list, &test_pixel, pp, dp);
+
+      if (test_pixel.colour_type != dp->output_colour_type)
+      {
+         char message[128];
+         size_t pos = safecat(message, sizeof message, 0, "colour type ");
+
+         pos = safecatn(message, sizeof message, pos, dp->output_colour_type);
+         pos = safecat(message, sizeof message, pos, " expected ");
+         pos = safecatn(message, sizeof message, pos, test_pixel.colour_type);
+
+         png_error(pp, message);
+      }
+
+      if (test_pixel.bit_depth != dp->output_bit_depth)
+      {
+         char message[128];
+         size_t pos = safecat(message, sizeof message, 0, "bit depth ");
+
+         pos = safecatn(message, sizeof message, pos, dp->output_bit_depth);
+         pos = safecat(message, sizeof message, pos, " expected ");
+         pos = safecatn(message, sizeof message, pos, test_pixel.bit_depth);
+
+         png_error(pp, message);
+      }
+
+      /* If both bit depth and colour type are correct check the sample depth.
+       * I believe these are both internal errors.
+       */
+      if (test_pixel.colour_type == PNG_COLOR_TYPE_PALETTE)
+      {
+         if (test_pixel.sample_depth != 8) /* oops - internal error! */
+            png_error(pp, "pngvalid: internal: palette sample depth not 8");
+      }
+      else if (test_pixel.sample_depth != dp->output_bit_depth)
+      {
+         char message[128];
+         size_t pos = safecat(message, sizeof message, 0,
+            "internal: sample depth ");
+
+         pos = safecatn(message, sizeof message, pos, dp->output_bit_depth);
+         pos = safecat(message, sizeof message, pos, " expected ");
+         pos = safecatn(message, sizeof message, pos, test_pixel.sample_depth);
+
+         png_error(pp, message);
+      }
+   }
+}
+
+static void
+transform_info(png_structp pp, png_infop pi)
+{
+   transform_info_imp(voidcast(transform_display*, png_get_progressive_ptr(pp)),
+      pp, pi);
+}
+
+static void
+transform_range_check(png_structp pp, unsigned int r, unsigned int g,
+   unsigned int b, unsigned int a, unsigned int in_digitized, double in,
+   unsigned int out, png_byte sample_depth, double err, double limit,
+   PNG_CONST char *name, double digitization_error)
+{
+   /* Compare the scaled, digitzed, values of our local calculation (in+-err)
+    * with the digitized values libpng produced;  'sample_depth' is the actual
+    * digitization depth of the libpng output colors (the bit depth except for
+    * palette images where it is always 8.)  The check on 'err' is to detect
+    * internal errors in pngvalid itself.
+    */
+   unsigned int max = (1U<<sample_depth)-1;
+   double in_min = ceil((in-err)*max - digitization_error);
+   double in_max = floor((in+err)*max + digitization_error);
+   if (err > limit || !(out >= in_min && out <= in_max))
+   {
+      char message[256];
+      size_t pos;
+
+      pos = safecat(message, sizeof message, 0, name);
+      pos = safecat(message, sizeof message, pos, " output value error: rgba(");
+      pos = safecatn(message, sizeof message, pos, r);
+      pos = safecat(message, sizeof message, pos, ",");
+      pos = safecatn(message, sizeof message, pos, g);
+      pos = safecat(message, sizeof message, pos, ",");
+      pos = safecatn(message, sizeof message, pos, b);
+      pos = safecat(message, sizeof message, pos, ",");
+      pos = safecatn(message, sizeof message, pos, a);
+      pos = safecat(message, sizeof message, pos, "): ");
+      pos = safecatn(message, sizeof message, pos, out);
+      pos = safecat(message, sizeof message, pos, " expected: ");
+      pos = safecatn(message, sizeof message, pos, in_digitized);
+      pos = safecat(message, sizeof message, pos, " (");
+      pos = safecatd(message, sizeof message, pos, (in-err)*max, 3);
+      pos = safecat(message, sizeof message, pos, "..");
+      pos = safecatd(message, sizeof message, pos, (in+err)*max, 3);
+      pos = safecat(message, sizeof message, pos, ")");
+
+      png_error(pp, message);
+   }
+}
+
+static void
+transform_image_validate(transform_display *dp, png_structp pp, png_infop pi)
+{
+   /* Constants for the loop below: */
+   PNG_CONST png_store* PNG_CONST ps = dp->this.ps;
+   PNG_CONST png_byte in_ct = dp->this.colour_type;
+   PNG_CONST png_byte in_bd = dp->this.bit_depth;
+   PNG_CONST png_uint_32 w = dp->this.w;
+   PNG_CONST png_uint_32 h = dp->this.h;
+   PNG_CONST png_byte out_ct = dp->output_colour_type;
+   PNG_CONST png_byte out_bd = dp->output_bit_depth;
+   PNG_CONST png_byte sample_depth = (png_byte)(out_ct ==
+      PNG_COLOR_TYPE_PALETTE ? 8 : out_bd);
+   PNG_CONST png_byte red_sBIT = dp->this.red_sBIT;
+   PNG_CONST png_byte green_sBIT = dp->this.green_sBIT;
+   PNG_CONST png_byte blue_sBIT = dp->this.blue_sBIT;
+   PNG_CONST png_byte alpha_sBIT = dp->this.alpha_sBIT;
+   PNG_CONST int have_tRNS = dp->this.is_transparent;
+   double digitization_error;
+
+   store_palette out_palette;
+   png_uint_32 y;
+
+   UNUSED(pi)
+
+   /* Check for row overwrite errors */
+   store_image_check(dp->this.ps, pp, 0);
+
+   /* Read the palette corresponding to the output if the output colour type
+    * indicates a palette, othewise set out_palette to garbage.
+    */
+   if (out_ct == PNG_COLOR_TYPE_PALETTE)
+   {
+      /* Validate that the palette count itself has not changed - this is not
+       * expected.
+       */
+      int npalette = (-1);
+
+      (void)read_palette(out_palette, &npalette, pp, pi);
+      if (npalette != dp->this.npalette)
+         png_error(pp, "unexpected change in palette size");
+
+      digitization_error = .5;
+   }
+   else
+   {
+      png_byte in_sample_depth;
+
+      memset(out_palette, 0x5e, sizeof out_palette);
+
+      /* assume-8-bit-calculations means assume that if the input has 8 bit
+       * (or less) samples and the output has 16 bit samples the calculations
+       * will be done with 8 bit precision, not 16.
+       *
+       * TODO: fix this in libpng; png_set_expand_16 should cause 16 bit
+       * calculations to be used throughout.
+       */
+      if (in_ct == PNG_COLOR_TYPE_PALETTE || in_bd < 16)
+         in_sample_depth = 8;
+      else
+         in_sample_depth = in_bd;
+
+      if (sample_depth != 16 || in_sample_depth > 8 ||
+         !dp->pm->calculations_use_input_precision)
+         digitization_error = .5;
+
+      /* Else errors are at 8 bit precision, scale .5 in 8 bits to the 16 bits:
+       */
+      else
+         digitization_error = .5 * 257;
+   }
+
+   for (y=0; y<h; ++y)
+   {
+      png_const_bytep PNG_CONST pRow = store_image_row(ps, pp, 0, y);
+      png_uint_32 x;
+
+      /* The original, standard, row pre-transforms. */
+      png_byte std[STANDARD_ROWMAX];
+
+      transform_row(pp, std, in_ct, in_bd, y);
+
+      /* Go through each original pixel transforming it and comparing with what
+       * libpng did to the same pixel.
+       */
+      for (x=0; x<w; ++x)
+      {
+         image_pixel in_pixel, out_pixel;
+         unsigned int r, g, b, a;
+
+         /* Find out what we think the pixel should be: */
+         image_pixel_init(&in_pixel, std, in_ct, in_bd, x, dp->this.palette);
+
+         in_pixel.red_sBIT = red_sBIT;
+         in_pixel.green_sBIT = green_sBIT;
+         in_pixel.blue_sBIT = blue_sBIT;
+         in_pixel.alpha_sBIT = alpha_sBIT;
+         in_pixel.have_tRNS = have_tRNS;
+
+         /* For error detection, below. */
+         r = in_pixel.red;
+         g = in_pixel.green;
+         b = in_pixel.blue;
+         a = in_pixel.alpha;
+
+         dp->transform_list->mod(dp->transform_list, &in_pixel, pp, dp);
+
+         /* Read the output pixel and compare it to what we got, we don't
+          * use the error field here, so no need to update sBIT.
+          */
+         image_pixel_init(&out_pixel, pRow, out_ct, out_bd, x, out_palette);
+
+         /* We don't expect changes to the index here even if the bit depth is
+          * changed.
+          */
+         if (in_ct == PNG_COLOR_TYPE_PALETTE &&
+            out_ct == PNG_COLOR_TYPE_PALETTE)
+         {
+            if (in_pixel.palette_index != out_pixel.palette_index)
+               png_error(pp, "unexpected transformed palette index");
+         }
+
+         /* Check the colours for palette images too - in fact the palette could
+          * be separately verified itself in most cases.
+          */
+         if (in_pixel.red != out_pixel.red)
+            transform_range_check(pp, r, g, b, a, in_pixel.red, in_pixel.redf,
+               out_pixel.red, sample_depth, in_pixel.rede,
+               dp->pm->limit + 1./(2*((1U<<in_pixel.red_sBIT)-1)), "red/gray",
+               digitization_error);
+
+         if ((out_ct & PNG_COLOR_MASK_COLOR) != 0 &&
+            in_pixel.green != out_pixel.green)
+            transform_range_check(pp, r, g, b, a, in_pixel.green,
+               in_pixel.greenf, out_pixel.green, sample_depth, in_pixel.greene,
+               dp->pm->limit + 1./(2*((1U<<in_pixel.green_sBIT)-1)), "green",
+               digitization_error);
+
+         if ((out_ct & PNG_COLOR_MASK_COLOR) != 0 &&
+            in_pixel.blue != out_pixel.blue)
+            transform_range_check(pp, r, g, b, a, in_pixel.blue, in_pixel.bluef,
+               out_pixel.blue, sample_depth, in_pixel.bluee,
+               dp->pm->limit + 1./(2*((1U<<in_pixel.blue_sBIT)-1)), "blue",
+               digitization_error);
+
+         if ((out_ct & PNG_COLOR_MASK_ALPHA) != 0 &&
+            in_pixel.alpha != out_pixel.alpha)
+            transform_range_check(pp, r, g, b, a, in_pixel.alpha,
+               in_pixel.alphaf, out_pixel.alpha, sample_depth, in_pixel.alphae,
+               dp->pm->limit + 1./(2*((1U<<in_pixel.alpha_sBIT)-1)), "alpha",
+               digitization_error);
+      } /* pixel (x) loop */
+   } /* row (y) loop */
+
+   /* Record that something was actually checked to avoid a false positive. */
+   dp->this.ps->validated = 1;
+}
+
+static void
+transform_end(png_structp pp, png_infop pi)
+{
+   transform_display *dp = voidcast(transform_display*,
+      png_get_progressive_ptr(pp));
+
+   if (!dp->this.speed)
+      transform_image_validate(dp, pp, pi);
+   else
+      dp->this.ps->validated = 1;
+}
+
+/* A single test run. */
+static void
+transform_test(png_modifier *pmIn, PNG_CONST png_uint_32 idIn,
+    PNG_CONST image_transform* transform_listIn, PNG_CONST char * volatile name)
+{
+   transform_display d;
+   context(&pmIn->this, fault);
+
+   transform_display_init(&d, pmIn, idIn, transform_listIn);
+
+   Try
+   {
+      size_t pos = 0;
+      png_structp pp;
+      png_infop pi;
+      char full_name[256];
+
+      /* Make sure the encoding fields are correct and enter the required
+       * modifications.
+       */
+      transform_set_encoding(&d);
+
+      /* Add any modifications required by the transform list. */
+      d.transform_list->ini(d.transform_list, &d);
+
+      /* Add the color space information, if any, to the name. */
+      pos = safecat(full_name, sizeof full_name, pos, name);
+      pos = safecat_current_encoding(full_name, sizeof full_name, pos, d.pm);
+
+      /* Get a png_struct for reading the image. */
+      pp = set_modifier_for_read(d.pm, &pi, d.this.id, full_name);
+      standard_palette_init(&d.this);
+
+#     if 0
+         /* Logging (debugging only) */
+         {
+            char buffer[256];
+
+            (void)store_message(&d.pm->this, pp, buffer, sizeof buffer, 0,
+               "running test");
+
+            fprintf(stderr, "%s\n", buffer);
+         }
+#     endif
+
+      /* Introduce the correct read function. */
+      if (d.pm->this.progressive)
+      {
+         /* Share the row function with the standard implementation. */
+         png_set_progressive_read_fn(pp, &d, transform_info, progressive_row,
+            transform_end);
+
+         /* Now feed data into the reader until we reach the end: */
+         modifier_progressive_read(d.pm, pp, pi);
+      }
+      else
+      {
+         /* modifier_read expects a png_modifier* */
+         png_set_read_fn(pp, d.pm, modifier_read);
+
+         /* Check the header values: */
+         png_read_info(pp, pi);
+
+         /* Process the 'info' requirements. Only one image is generated */
+         transform_info_imp(&d, pp, pi);
+
+         sequential_row(&d.this, pp, pi, -1, 0);
+
+         if (!d.this.speed)
+            transform_image_validate(&d, pp, pi);
+         else
+            d.this.ps->validated = 1;
+      }
+
+      modifier_reset(d.pm);
+   }
+
+   Catch(fault)
+   {
+      modifier_reset((png_modifier*)fault);
+   }
+}
+
+/* The transforms: */
+#define ITSTRUCT(name) image_transform_##name
+#define ITDATA(name) image_transform_data_##name
+#define image_transform_ini image_transform_default_ini
+#define IT(name)\
+static image_transform ITSTRUCT(name) =\
+{\
+   #name,\
+   1, /*enable*/\
+   &PT, /*list*/\
+   0, /*global_use*/\
+   0, /*local_use*/\
+   0, /*next*/\
+   image_transform_ini,\
+   image_transform_png_set_##name##_set,\
+   image_transform_png_set_##name##_mod,\
+   image_transform_png_set_##name##_add\
+}
+#define PT ITSTRUCT(end) /* stores the previous transform */
+
+/* To save code: */
+static void
+image_transform_default_ini(PNG_CONST image_transform *this,
+    transform_display *that)
+{
+   this->next->ini(this->next, that);
+}
+
+static int
+image_transform_default_add(image_transform *this,
+    PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth)
+{
+   UNUSED(colour_type)
+   UNUSED(bit_depth)
+
+   this->next = *that;
+   *that = this;
+
+   return 1;
+}
+
+#ifdef PNG_READ_EXPAND_SUPPORTED
+/* png_set_palette_to_rgb */
+static void
+image_transform_png_set_palette_to_rgb_set(PNG_CONST image_transform *this,
+    transform_display *that, png_structp pp, png_infop pi)
+{
+   png_set_palette_to_rgb(pp);
+   this->next->set(this->next, that, pp, pi);
+}
+
+static void
+image_transform_png_set_palette_to_rgb_mod(PNG_CONST image_transform *this,
+    image_pixel *that, png_structp pp, PNG_CONST transform_display *display)
+{
+   if (that->colour_type == PNG_COLOR_TYPE_PALETTE)
+      image_pixel_convert_PLTE(that);
+
+   this->next->mod(this->next, that, pp, display);
+}
+
+static int
+image_transform_png_set_palette_to_rgb_add(image_transform *this,
+    PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth)
+{
+   UNUSED(bit_depth)
+
+   this->next = *that;
+   *that = this;
+
+   return colour_type == PNG_COLOR_TYPE_PALETTE;
+}
+
+IT(palette_to_rgb);
+#undef PT
+#define PT ITSTRUCT(palette_to_rgb)
+#endif /* PNG_READ_EXPAND_SUPPORTED */
+
+#ifdef PNG_READ_EXPAND_SUPPORTED
+/* png_set_tRNS_to_alpha */
+static void
+image_transform_png_set_tRNS_to_alpha_set(PNG_CONST image_transform *this,
+   transform_display *that, png_structp pp, png_infop pi)
+{
+   png_set_tRNS_to_alpha(pp);
+   this->next->set(this->next, that, pp, pi);
+}
+
+static void
+image_transform_png_set_tRNS_to_alpha_mod(PNG_CONST image_transform *this,
+   image_pixel *that, png_structp pp, PNG_CONST transform_display *display)
+{
+   /* LIBPNG BUG: this always forces palette images to RGB. */
+   if (that->colour_type == PNG_COLOR_TYPE_PALETTE)
+      image_pixel_convert_PLTE(that);
+
+   /* This effectively does an 'expand' only if there is some transparency to
+    * convert to an alpha channel.
+    */
+   if (that->have_tRNS)
+      image_pixel_add_alpha(that, &display->this);
+
+   /* LIBPNG BUG: otherwise libpng still expands to 8 bits! */
+   else
+   {
+      if (that->bit_depth < 8)
+         that->bit_depth =8;
+      if (that->sample_depth < 8)
+         that->sample_depth = 8;
+   }
+
+   this->next->mod(this->next, that, pp, display);
+}
+
+static int
+image_transform_png_set_tRNS_to_alpha_add(image_transform *this,
+    PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth)
+{
+   UNUSED(bit_depth)
+
+   this->next = *that;
+   *that = this;
+
+   /* We don't know yet whether there will be a tRNS chunk, but we know that
+    * this transformation should do nothing if there already is an alpha
+    * channel.
+    */
+   return (colour_type & PNG_COLOR_MASK_ALPHA) == 0;
+}
+
+IT(tRNS_to_alpha);
+#undef PT
+#define PT ITSTRUCT(tRNS_to_alpha)
+#endif /* PNG_READ_EXPAND_SUPPORTED */
+
+#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
+/* png_set_gray_to_rgb */
+static void
+image_transform_png_set_gray_to_rgb_set(PNG_CONST image_transform *this,
+    transform_display *that, png_structp pp, png_infop pi)
+{
+   png_set_gray_to_rgb(pp);
+   this->next->set(this->next, that, pp, pi);
+}
+
+static void
+image_transform_png_set_gray_to_rgb_mod(PNG_CONST image_transform *this,
+    image_pixel *that, png_structp pp, PNG_CONST transform_display *display)
+{
+   /* NOTE: we can actually pend the tRNS processing at this point because we
+    * can correctly recognize the original pixel value even though we have
+    * mapped the one gray channel to the three RGB ones, but in fact libpng
+    * doesn't do this, so we don't either.
+    */
+   if ((that->colour_type & PNG_COLOR_MASK_COLOR) == 0 && that->have_tRNS)
+      image_pixel_add_alpha(that, &display->this);
+
+   /* Simply expand the bit depth and alter the colour type as required. */
+   if (that->colour_type == PNG_COLOR_TYPE_GRAY)
+   {
+      /* RGB images have a bit depth at least equal to '8' */
+      if (that->bit_depth < 8)
+         that->sample_depth = that->bit_depth = 8;
+
+      /* And just changing the colour type works here because the green and blue
+       * channels are being maintained in lock-step with the red/gray:
+       */
+      that->colour_type = PNG_COLOR_TYPE_RGB;
+   }
+
+   else if (that->colour_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+      that->colour_type = PNG_COLOR_TYPE_RGB_ALPHA;
+
+   this->next->mod(this->next, that, pp, display);
+}
+
+static int
+image_transform_png_set_gray_to_rgb_add(image_transform *this,
+    PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth)
+{
+   UNUSED(bit_depth)
+
+   this->next = *that;
+   *that = this;
+
+   return (colour_type & PNG_COLOR_MASK_COLOR) == 0;
+}
+
+IT(gray_to_rgb);
+#undef PT
+#define PT ITSTRUCT(gray_to_rgb)
+#endif /* PNG_READ_GRAY_TO_RGB_SUPPORTED */
+
+#ifdef PNG_READ_EXPAND_SUPPORTED
+/* png_set_expand */
+static void
+image_transform_png_set_expand_set(PNG_CONST image_transform *this,
+    transform_display *that, png_structp pp, png_infop pi)
+{
+   png_set_expand(pp);
+   this->next->set(this->next, that, pp, pi);
+}
+
+static void
+image_transform_png_set_expand_mod(PNG_CONST image_transform *this,
+    image_pixel *that, png_structp pp, PNG_CONST transform_display *display)
+{
+   /* The general expand case depends on what the colour type is: */
+   if (that->colour_type == PNG_COLOR_TYPE_PALETTE)
+      image_pixel_convert_PLTE(that);
+   else if (that->bit_depth < 8) /* grayscale */
+      that->sample_depth = that->bit_depth = 8;
+
+   if (that->have_tRNS)
+      image_pixel_add_alpha(that, &display->this);
+
+   this->next->mod(this->next, that, pp, display);
+}
+
+static int
+image_transform_png_set_expand_add(image_transform *this,
+    PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth)
+{
+   UNUSED(bit_depth)
+
+   this->next = *that;
+   *that = this;
+
+   /* 'expand' should do nothing for RGBA or GA input - no tRNS and the bit
+    * depth is at least 8 already.
+    */
+   return (colour_type & PNG_COLOR_MASK_ALPHA) == 0;
+}
+
+IT(expand);
+#undef PT
+#define PT ITSTRUCT(expand)
+#endif /* PNG_READ_EXPAND_SUPPORTED */
+
+#ifdef PNG_READ_EXPAND_SUPPORTED
+/* png_set_expand_gray_1_2_4_to_8
+ * LIBPNG BUG: this just does an 'expand'
+ */
+static void
+image_transform_png_set_expand_gray_1_2_4_to_8_set(
+    PNG_CONST image_transform *this, transform_display *that, png_structp pp,
+    png_infop pi)
+{
+   png_set_expand_gray_1_2_4_to_8(pp);
+   this->next->set(this->next, that, pp, pi);
+}
+
+static void
+image_transform_png_set_expand_gray_1_2_4_to_8_mod(
+    PNG_CONST image_transform *this, image_pixel *that, png_structp pp,
+    PNG_CONST transform_display *display)
+{
+   image_transform_png_set_expand_mod(this, that, pp, display);
+}
+
+static int
+image_transform_png_set_expand_gray_1_2_4_to_8_add(image_transform *this,
+    PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth)
+{
+   return image_transform_png_set_expand_add(this, that, colour_type,
+      bit_depth);
+}
+
+IT(expand_gray_1_2_4_to_8);
+#undef PT
+#define PT ITSTRUCT(expand_gray_1_2_4_to_8)
+#endif /* PNG_READ_EXPAND_SUPPORTED */
+
+#ifdef PNG_READ_EXPAND_16_SUPPORTED
+/* png_set_expand_16 */
+static void
+image_transform_png_set_expand_16_set(PNG_CONST image_transform *this,
+    transform_display *that, png_structp pp, png_infop pi)
+{
+   png_set_expand_16(pp);
+   this->next->set(this->next, that, pp, pi);
+}
+
+static void
+image_transform_png_set_expand_16_mod(PNG_CONST image_transform *this,
+    image_pixel *that, png_structp pp, PNG_CONST transform_display *display)
+{
+   /* Expect expand_16 to expand everything to 16 bits as a result of also
+    * causing 'expand' to happen.
+    */
+   if (that->colour_type == PNG_COLOR_TYPE_PALETTE)
+      image_pixel_convert_PLTE(that);
+
+   if (that->have_tRNS)
+      image_pixel_add_alpha(that, &display->this);
+
+   if (that->bit_depth < 16)
+      that->sample_depth = that->bit_depth = 16;
+
+   this->next->mod(this->next, that, pp, display);
+}
+
+static int
+image_transform_png_set_expand_16_add(image_transform *this,
+    PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth)
+{
+   UNUSED(colour_type)
+
+   this->next = *that;
+   *that = this;
+
+   /* expand_16 does something unless the bit depth is already 16. */
+   return bit_depth < 16;
+}
+
+IT(expand_16);
+#undef PT
+#define PT ITSTRUCT(expand_16)
+#endif /* PNG_READ_EXPAND_16_SUPPORTED */
+
+#ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED  /* API added in 1.5.4 */
+/* png_set_scale_16 */
+static void
+image_transform_png_set_scale_16_set(PNG_CONST image_transform *this,
+    transform_display *that, png_structp pp, png_infop pi)
+{
+   png_set_scale_16(pp);
+   this->next->set(this->next, that, pp, pi);
+}
+
+static void
+image_transform_png_set_scale_16_mod(PNG_CONST image_transform *this,
+    image_pixel *that, png_structp pp, PNG_CONST transform_display *display)
+{
+   if (that->bit_depth == 16)
+   {
+      that->sample_depth = that->bit_depth = 8;
+      if (that->red_sBIT > 8) that->red_sBIT = 8;
+      if (that->green_sBIT > 8) that->green_sBIT = 8;
+      if (that->blue_sBIT > 8) that->blue_sBIT = 8;
+      if (that->alpha_sBIT > 8) that->alpha_sBIT = 8;
+   }
+
+   this->next->mod(this->next, that, pp, display);
+}
+
+static int
+image_transform_png_set_scale_16_add(image_transform *this,
+    PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth)
+{
+   UNUSED(colour_type)
+
+   this->next = *that;
+   *that = this;
+
+   return bit_depth > 8;
+}
+
+IT(scale_16);
+#undef PT
+#define PT ITSTRUCT(scale_16)
+#endif /* PNG_READ_SCALE_16_TO_8_SUPPORTED (1.5.4 on) */
+
+#ifdef PNG_READ_16_TO_8_SUPPORTED /* the default before 1.5.4 */
+/* png_set_strip_16 */
+static void
+image_transform_png_set_strip_16_set(PNG_CONST image_transform *this,
+    transform_display *that, png_structp pp, png_infop pi)
+{
+   png_set_strip_16(pp);
+   this->next->set(this->next, that, pp, pi);
+}
+
+static void
+image_transform_png_set_strip_16_mod(PNG_CONST image_transform *this,
+    image_pixel *that, png_structp pp, PNG_CONST transform_display *display)
+{
+   if (that->bit_depth == 16)
+   {
+      that->sample_depth = that->bit_depth = 8;
+      if (that->red_sBIT > 8) that->red_sBIT = 8;
+      if (that->green_sBIT > 8) that->green_sBIT = 8;
+      if (that->blue_sBIT > 8) that->blue_sBIT = 8;
+      if (that->alpha_sBIT > 8) that->alpha_sBIT = 8;
+
+      /* Prior to 1.5.4 png_set_strip_16 would use an 'accurate' method if this
+       * configuration option is set.  From 1.5.4 the flag is never set and the
+       * 'scale' API (above) must be used.
+       */
+#     ifdef PNG_READ_ACCURATE_SCALE_SUPPORTED
+#        if PNG_LIBPNG_VER >= 10504
+#           error PNG_READ_ACCURATE_SCALE should not be set
+#        endif
+
+         /* The strip 16 algorithm drops the low 8 bits rather than calculating
+          * 1/257, so we need to adjust the permitted errors appropriately:
+          * Notice that this is only relevant prior to the addition of the
+          * png_set_scale_16 API in 1.5.4 (but 1.5.4+ always defines the above!)
+          */
+         {
+            PNG_CONST double d = (255-128.5)/65535;
+            that->rede += d;
+            that->greene += d;
+            that->bluee += d;
+            that->alphae += d;
+         }
+#     endif
+   }
+
+   this->next->mod(this->next, that, pp, display);
+}
+
+static int
+image_transform_png_set_strip_16_add(image_transform *this,
+    PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth)
+{
+   UNUSED(colour_type)
+
+   this->next = *that;
+   *that = this;
+
+   return bit_depth > 8;
+}
+
+IT(strip_16);
+#undef PT
+#define PT ITSTRUCT(strip_16)
+#endif /* PNG_READ_16_TO_8_SUPPORTED */
+
+#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED
+/* png_set_strip_alpha */
+static void
+image_transform_png_set_strip_alpha_set(PNG_CONST image_transform *this,
+    transform_display *that, png_structp pp, png_infop pi)
+{
+   png_set_strip_alpha(pp);
+   this->next->set(this->next, that, pp, pi);
+}
+
+static void
+image_transform_png_set_strip_alpha_mod(PNG_CONST image_transform *this,
+    image_pixel *that, png_structp pp, PNG_CONST transform_display *display)
+{
+   if (that->colour_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+      that->colour_type = PNG_COLOR_TYPE_GRAY;
+   else if (that->colour_type == PNG_COLOR_TYPE_RGB_ALPHA)
+      that->colour_type = PNG_COLOR_TYPE_RGB;
+
+   that->have_tRNS = 0;
+   that->alphaf = 1;
+
+   this->next->mod(this->next, that, pp, display);
+}
+
+static int
+image_transform_png_set_strip_alpha_add(image_transform *this,
+    PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth)
+{
+   UNUSED(bit_depth)
+
+   this->next = *that;
+   *that = this;
+
+   return (colour_type & PNG_COLOR_MASK_ALPHA) != 0;
+}
+
+IT(strip_alpha);
+#undef PT
+#define PT ITSTRUCT(strip_alpha)
+#endif /* PNG_READ_STRIP_ALPHA_SUPPORTED */
+
+#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
+/* png_set_rgb_to_gray(png_structp, int err_action, double red, double green)
+ * png_set_rgb_to_gray_fixed(png_structp, int err_action, png_fixed_point red,
+ *    png_fixed_point green)
+ * png_get_rgb_to_gray_status
+ *
+ * The 'default' test here uses values known to be used inside libpng:
+ *
+ *   red:    6968
+ *   green: 23434
+ *   blue:   2366
+ *
+ * These values are being retained for compatibility, along with the somewhat
+ * broken truncation calculation in the fast-and-inaccurate code path.  Older
+ * versions of libpng will fail the accuracy tests below because they use the
+ * truncation algorithm everywhere.
+ */
+#define data ITDATA(rgb_to_gray)
+static struct
+{
+   double gamma;      /* File gamma to use in processing */
+
+   /* The following are the parameters for png_set_rgb_to_gray: */
+#  ifdef PNG_FLOATING_POINT_SUPPORTED
+      double red_to_set;
+      double green_to_set;
+#  else
+      png_fixed_point red_to_set;
+      png_fixed_point green_to_set;
+#  endif
+
+   /* The actual coefficients: */
+   double red_coefficient;
+   double green_coefficient;
+   double blue_coefficient;
+
+   /* Set if the coeefficients have been overridden. */
+   int coefficients_overridden;
+} data;
+
+#undef image_transform_ini
+#define image_transform_ini image_transform_png_set_rgb_to_gray_ini
+static void
+image_transform_png_set_rgb_to_gray_ini(PNG_CONST image_transform *this,
+    transform_display *that)
+{
+   png_modifier *pm = that->pm;
+   PNG_CONST color_encoding *e = pm->current_encoding;
+
+   UNUSED(this)
+
+   /* Since we check the encoding this flag must be set: */
+   pm->test_uses_encoding = 1;
+
+   /* If 'e' is not NULL chromaticity information is present and either a cHRM
+    * or an sRGB chunk will be inserted.
+    */
+   if (e != 0)
+   {
+      /* Coefficients come from the encoding, but may need to be normalized to a
+       * white point Y of 1.0
+       */
+      PNG_CONST double whiteY = e->red.Y + e->green.Y + e->blue.Y;
+
+      data.red_coefficient = e->red.Y;
+      data.green_coefficient = e->green.Y;
+      data.blue_coefficient = e->blue.Y;
+
+      if (whiteY != 1)
+      {
+         data.red_coefficient /= whiteY;
+         data.green_coefficient /= whiteY;
+         data.blue_coefficient /= whiteY;
+      }
+   }
+
+   else
+   {
+      /* The default (built in) coeffcients, as above: */
+      data.red_coefficient = 6968 / 32768.;
+      data.green_coefficient = 23434 / 32768.;
+      data.blue_coefficient = 2366 / 32768.;
+   }
+
+   data.gamma = pm->current_gamma;
+
+   /* If not set then the calculations assume linear encoding (implicitly): */
+   if (data.gamma == 0)
+      data.gamma = 1;
+
+   /* The arguments to png_set_rgb_to_gray can override the coefficients implied
+    * by the color space encoding.  If doing exhaustive checks do the override
+    * in each case, otherwise do it randomly.
+    */
+   if (pm->test_exhaustive)
+   {
+      /* First time in coefficients_overridden is 0, the following sets it to 1,
+       * so repeat if it is set.  If a test fails this may mean we subsequently
+       * skip a non-override test, ignore that.
+       */
+      data.coefficients_overridden = !data.coefficients_overridden;
+      pm->repeat = data.coefficients_overridden != 0;
+   }
+
+   else
+      data.coefficients_overridden = random_choice();
+
+   if (data.coefficients_overridden)
+   {
+      /* These values override the color encoding defaults, simply use random
+       * numbers.
+       */
+      png_uint_32 ru;
+      double total;
+
+      RANDOMIZE(ru);
+      data.green_coefficient = total = (ru & 0xffff) / 65535.;
+      ru >>= 16;
+      data.red_coefficient = (1 - total) * (ru & 0xffff) / 65535.;
+      total += data.red_coefficient;
+      data.blue_coefficient = 1 - total;
+
+#     ifdef PNG_FLOATING_POINT_SUPPORTED
+         data.red_to_set = data.red_coefficient;
+         data.green_to_set = data.green_coefficient;
+#     else
+         data.red_to_set = fix(data.red_coefficient);
+         data.green_to_set = fix(data.green_coefficient);
+#     endif
+
+      /* The following just changes the error messages: */
+      pm->encoding_ignored = 1;
+   }
+
+   else
+   {
+      data.red_to_set = -1;
+      data.green_to_set = -1;
+   }
+
+   /* Adjust the error limit in the png_modifier because of the larger errors
+    * produced in the digitization during the gamma handling.
+    */
+   if (data.gamma != 1) /* Use gamma tables */
+   {
+      if (that->this.bit_depth == 16 || pm->assume_16_bit_calculations)
+      {
+         /* The 16 bit case ends up producing a maximum error of about
+          * +/-5 in 65535, allow for +/-8 with the given gamma.
+          */
+         that->pm->limit += pow(8./65535, data.gamma);
+      }
+
+      else
+      {
+         /* Rounding to 8 bits in the linear space causes massive errors which
+          * will trigger the error check in transform_range_check.  Fix that
+          * here by taking the gamma encoding into account.
+          */
+         that->pm->limit += pow(1./255, data.gamma);
+      }
+   }
+
+   else
+   {
+      /* With no gamma correction a large error comes from the truncation of the
+       * calculation in the 8 bit case, allow for that here.
+       */
+      if (that->this.bit_depth != 16)
+         that->pm->limit += 4E-3;
+   }
+}
+
+static void
+image_transform_png_set_rgb_to_gray_set(PNG_CONST image_transform *this,
+    transform_display *that, png_structp pp, png_infop pi)
+{
+   PNG_CONST int error_action = 1; /* no error, no defines in png.h */
+
+#  ifdef PNG_FLOATING_POINT_SUPPORTED
+      png_set_rgb_to_gray(pp, error_action, data.red_to_set, data.green_to_set);
+#  else
+      png_set_rgb_to_gray_fixed(pp, error_action, data.red_to_set,
+         data.green_to_set);
+#  endif
+
+#  ifdef PNG_READ_cHRM_SUPPORTED
+      if (that->pm->current_encoding != 0)
+      {
+         /* We have an encoding so a cHRM chunk may have been set; if so then
+          * check that the libpng APIs give the correct (X,Y,Z) values within
+          * some margin of error for the round trip through the chromaticity
+          * form.
+          */
+#        ifdef PNG_FLOATING_POINT_SUPPORTED
+#           define API_function png_get_cHRM_XYZ
+#           define API_form "FP"
+#           define API_type double
+#           define API_cvt(x) (x)
+#        else
+#           define API_function png_get_cHRM_XYZ_fixed
+#           define API_form "fixed"
+#           define API_type png_fixed_point
+#           define API_cvt(x) ((double)(x)/PNG_FP_1)
+#        endif
+
+         API_type rX, gX, bX;
+         API_type rY, gY, bY;
+         API_type rZ, gZ, bZ;
+
+         if ((API_function(pp, pi, &rX, &rY, &rZ, &gX, &gY, &gZ, &bX, &bY, &bZ)
+               & PNG_INFO_cHRM) != 0)
+         {
+            double maxe;
+            PNG_CONST char *el;
+            color_encoding e, o;
+
+            /* Expect libpng to return a normalized result, but the original
+             * color space encoding may not be normalized.
+             */
+            modifier_current_encoding(that->pm, &o);
+            normalize_color_encoding(&o);
+
+            /* Sanity check the pngvalid code - the coefficients should match
+             * the normalized Y values of the encoding unless they were
+             * overridden.
+             */
+            if (data.red_to_set == -1 && data.green_to_set == -1 &&
+               (fabs(o.red.Y - data.red_coefficient) > DBL_EPSILON ||
+               fabs(o.green.Y - data.green_coefficient) > DBL_EPSILON ||
+               fabs(o.blue.Y - data.blue_coefficient) > DBL_EPSILON))
+               png_error(pp, "internal pngvalid cHRM coefficient error");
+
+            /* Generate a colour space encoding. */
+            e.gamma = o.gamma; /* not used */
+            e.red.X = API_cvt(rX);
+            e.red.Y = API_cvt(rY);
+            e.red.Z = API_cvt(rZ);
+            e.green.X = API_cvt(gX);
+            e.green.Y = API_cvt(gY);
+            e.green.Z = API_cvt(gZ);
+            e.blue.X = API_cvt(bX);
+            e.blue.Y = API_cvt(bY);
+            e.blue.Z = API_cvt(bZ);
+
+            /* This should match the original one from the png_modifier, within
+             * the range permitted by the libpng fixed point representation.
+             */
+            maxe = 0;
+            el = "-"; /* Set to element name with error */
+
+#           define CHECK(col,x)\
+            {\
+               double err = fabs(o.col.x - e.col.x);\
+               if (err > maxe)\
+               {\
+                  maxe = err;\
+                  el = #col "(" #x ")";\
+               }\
+            }
+
+            CHECK(red,X)
+            CHECK(red,Y)
+            CHECK(red,Z)
+            CHECK(green,X)
+            CHECK(green,Y)
+            CHECK(green,Z)
+            CHECK(blue,X)
+            CHECK(blue,Y)
+            CHECK(blue,Z)
+
+            /* Here in both fixed and floating cases to check the values read
+             * from the cHRm chunk.  PNG uses fixed point in the cHRM chunk, so
+             * we can't expect better than +/-.5E-5 on the result, allow 1E-5.
+             */
+            if (maxe >= 1E-5)
+            {
+               size_t pos = 0;
+               char buffer[256];
+
+               pos = safecat(buffer, sizeof buffer, pos, API_form);
+               pos = safecat(buffer, sizeof buffer, pos, " cHRM ");
+               pos = safecat(buffer, sizeof buffer, pos, el);
+               pos = safecat(buffer, sizeof buffer, pos, " error: ");
+               pos = safecatd(buffer, sizeof buffer, pos, maxe, 7);
+               pos = safecat(buffer, sizeof buffer, pos, " ");
+               /* Print the color space without the gamma value: */
+               pos = safecat_color_encoding(buffer, sizeof buffer, pos, &o, 0);
+               pos = safecat(buffer, sizeof buffer, pos, " -> ");
+               pos = safecat_color_encoding(buffer, sizeof buffer, pos, &e, 0);
+
+               png_error(pp, buffer);
+            }
+         }
+      }
+#  endif /* READ_cHRM */
+
+   this->next->set(this->next, that, pp, pi);
+}
+
+static void
+image_transform_png_set_rgb_to_gray_mod(PNG_CONST image_transform *this,
+    image_pixel *that, png_structp pp, PNG_CONST transform_display *display)
+{
+   if ((that->colour_type & PNG_COLOR_MASK_COLOR) != 0)
+   {
+      double gray, err;
+
+      if (that->colour_type == PNG_COLOR_TYPE_PALETTE)
+         image_pixel_convert_PLTE(that);
+
+      /* Image now has RGB channels... */
+      {
+         PNG_CONST png_modifier *pm = display->pm;
+         PNG_CONST unsigned int sample_depth = that->sample_depth;
+         int isgray;
+         double r, g, b;
+         double rlo, rhi, glo, ghi, blo, bhi, graylo, grayhi;
+
+         /* Do this using interval arithmetic, otherwise it is too difficult to
+          * handle the errors correctly.
+          *
+          * To handle the gamma correction work out the upper and lower bounds
+          * of the digitized value.  Assume rounding here - normally the values
+          * will be identical after this operation if there is only one
+          * transform, feel free to delete the png_error checks on this below in
+          * the future (this is just me trying to ensure it works!)
+          */
+         r = rlo = rhi = that->redf;
+         rlo -= that->rede;
+         rlo = digitize(pm, rlo, sample_depth, 1/*round*/);
+         rhi += that->rede;
+         rhi = digitize(pm, rhi, sample_depth, 1/*round*/);
+
+         g = glo = ghi = that->greenf;
+         glo -= that->greene;
+         glo = digitize(pm, glo, sample_depth, 1/*round*/);
+         ghi += that->greene;
+         ghi = digitize(pm, ghi, sample_depth, 1/*round*/);
+
+         b = blo = bhi = that->bluef;
+         blo -= that->bluee;
+         blo = digitize(pm, blo, sample_depth, 1/*round*/);
+         bhi += that->greene;
+         bhi = digitize(pm, bhi, sample_depth, 1/*round*/);
+
+         isgray = r==g && g==b;
+
+         if (data.gamma != 1)
+         {
+            PNG_CONST double power = 1/data.gamma;
+            PNG_CONST double abse = abserr(pm, sample_depth, sample_depth);
+
+            /* 'abse' is the absolute error permitted in linear calculations. It
+             * is used here to capture the error permitted in the handling
+             * (undoing) of the gamma encoding.  Once again digitization occurs
+             * to handle the upper and lower bounds of the values.  This is
+             * where the real errors are introduced.
+             */
+            r = pow(r, power);
+            rlo = digitize(pm, pow(rlo, power)-abse, sample_depth, 1);
+            rhi = digitize(pm, pow(rhi, power)+abse, sample_depth, 1);
+
+            g = pow(g, power);
+            glo = digitize(pm, pow(glo, power)-abse, sample_depth, 1);
+            ghi = digitize(pm, pow(ghi, power)+abse, sample_depth, 1);
+
+            b = pow(b, power);
+            blo = digitize(pm, pow(blo, power)-abse, sample_depth, 1);
+            bhi = digitize(pm, pow(bhi, power)+abse, sample_depth, 1);
+         }
+
+         /* Now calculate the actual gray values.  Although the error in the
+          * coefficients depends on whether they were specified on the command
+          * line (in which case truncation to 15 bits happened) or not (rounding
+          * was used) the maxium error in an individual coefficient is always
+          * 1/32768, because even in the rounding case the requirement that
+          * coefficients add up to 32768 can cause a larger rounding error.
+          *
+          * The only time when rounding doesn't occur in 1.5.5 and later is when
+          * the non-gamma code path is used for less than 16 bit data.
+          */
+         gray = r * data.red_coefficient + g * data.green_coefficient +
+            b * data.blue_coefficient;
+
+         {
+            PNG_CONST int do_round = data.gamma != 1 || sample_depth == 16;
+            PNG_CONST double ce = 1. / 32768;
+
+            graylo = digitize(pm, rlo * (data.red_coefficient-ce) +
+               glo * (data.green_coefficient-ce) +
+               blo * (data.blue_coefficient-ce), sample_depth, do_round);
+            if (graylo <= 0)
+               graylo = 0;
+
+            grayhi = digitize(pm, rhi * (data.red_coefficient+ce) +
+               ghi * (data.green_coefficient+ce) +
+               bhi * (data.blue_coefficient+ce), sample_depth, do_round);
+            if (grayhi >= 1)
+               grayhi = 1;
+         }
+
+         /* And invert the gamma. */
+         if (data.gamma != 1)
+         {
+            PNG_CONST double power = data.gamma;
+
+            gray = pow(gray, power);
+            graylo = digitize(pm, pow(graylo, power), sample_depth, 1);
+            grayhi = digitize(pm, pow(grayhi, power), sample_depth, 1);
+         }
+
+         /* Now the error can be calculated.
+          *
+          * If r==g==b because there is no overall gamma correction libpng
+          * currently preserves the original value.
+          */
+         if (isgray)
+            err = (that->rede + that->greene + that->bluee)/3;
+
+         else
+         {
+            err = fabs(grayhi-gray);
+            if (fabs(gray - graylo) > err)
+               err = fabs(graylo-gray);
+
+            /* Check that this worked: */
+            if (err > display->pm->limit)
+            {
+               size_t pos = 0;
+               char buffer[128];
+
+               pos = safecat(buffer, sizeof buffer, pos, "rgb_to_gray error ");
+               pos = safecatd(buffer, sizeof buffer, pos, err, 6);
+               pos = safecat(buffer, sizeof buffer, pos, " exceeds limit ");
+               pos = safecatd(buffer, sizeof buffer, pos,
+                  display->pm->limit, 6);
+               png_error(pp, buffer);
+            }
+         }
+      }
+
+      that->bluef = that->greenf = that->redf = gray;
+      that->bluee = that->greene = that->rede = err;
+
+      /* The sBIT is the minium of the three colour channel sBITs. */
+      if (that->red_sBIT > that->green_sBIT)
+         that->red_sBIT = that->green_sBIT;
+      if (that->red_sBIT > that->blue_sBIT)
+         that->red_sBIT = that->blue_sBIT;
+      that->blue_sBIT = that->green_sBIT = that->red_sBIT;
+
+      /* And remove the colour bit in the type: */
+      if (that->colour_type == PNG_COLOR_TYPE_RGB)
+         that->colour_type = PNG_COLOR_TYPE_GRAY;
+      else if (that->colour_type == PNG_COLOR_TYPE_RGB_ALPHA)
+         that->colour_type = PNG_COLOR_TYPE_GRAY_ALPHA;
+   }
+
+   this->next->mod(this->next, that, pp, display);
+}
+
+static int
+image_transform_png_set_rgb_to_gray_add(image_transform *this,
+    PNG_CONST image_transform **that, png_byte colour_type, png_byte bit_depth)
+{
+   UNUSED(bit_depth)
+
+   this->next = *that;
+   *that = this;
+
+   return (colour_type & PNG_COLOR_MASK_COLOR) != 0;
+}
+
+#undef data
+IT(rgb_to_gray);
+#undef PT
+#define PT ITSTRUCT(rgb_to_gray)
+#undef image_transform_ini
+#define image_transform_ini image_transform_default_ini
+#endif /* PNG_READ_RGB_TO_GRAY_SUPPORTED */
+
+#ifdef PNG_READ_BACKGROUND_SUPPORTED
+/* png_set_background(png_structp, png_const_color_16p background_color,
+ *    int background_gamma_code, int need_expand, double background_gamma)
+ * png_set_background_fixed(png_structp, png_const_color_16p background_color,
+ *    int background_gamma_code, int need_expand,
+ *    png_fixed_point background_gamma)
+ *
+ * As with rgb_to_gray this ignores the gamma (at present.)
+*/
+#define data ITDATA(background)
+static image_pixel data;
+
+static void
+image_transform_png_set_background_set(PNG_CONST image_transform *this,
+    transform_display *that, png_structp pp, png_infop pi)
+{
+   png_byte colour_type, bit_depth;
+   png_byte random_bytes[8]; /* 8 bytes - 64 bits - the biggest pixel */
+   png_color_16 back;
+
+   /* We need a background colour, because we don't know exactly what transforms
+    * have been set we have to supply the colour in the original file format and
+    * so we need to know what that is!  The background colour is stored in the
+    * transform_display.
+    */
+   RANDOMIZE(random_bytes);
+
+   /* Read the random value, for colour type 3 the background colour is actually
+    * expressed as a 24bit rgb, not an index.
+    */
+   colour_type = that->this.colour_type;
+   if (colour_type == 3)
+   {
+      colour_type = PNG_COLOR_TYPE_RGB;
+      bit_depth = 8;
+   }
+
+   else
+      bit_depth = that->this.bit_depth;
+
+   image_pixel_init(&data, random_bytes, colour_type,
+      bit_depth, 0/*x*/, 0/*unused: palette*/);
+
+   /* Extract the background colour from this image_pixel, but make sure the
+    * unused fields of 'back' are garbage.
+    */
+   RANDOMIZE(back);
+
+   if (colour_type & PNG_COLOR_MASK_COLOR)
+   {
+      back.red = (png_uint_16)data.red;
+      back.green = (png_uint_16)data.green;
+      back.blue = (png_uint_16)data.blue;
+   }
+
+   else
+      back.gray = (png_uint_16)data.red;
+
+#  ifdef PNG_FLOATING_POINT_SUPPORTED
+      png_set_background(pp, &back, PNG_BACKGROUND_GAMMA_FILE, 1/*need expand*/,
+         0);
+#  else
+      png_set_background_fixed(pp, &back, PNG_BACKGROUND_GAMMA_FILE,
+         1/*need expand*/, 0);
+#  endif
+
+   this->next->set(this->next, that, pp, pi);
+}
+
+static void
+image_transform_png_set_background_mod(PNG_CONST image_transform *this,
+    image_pixel *that, png_structp pp, PNG_CONST transform_display *display)
+{
+   /* Check for tRNS first: */
+   if (that->have_tRNS && that->colour_type != PNG_COLOR_TYPE_PALETTE)
+      image_pixel_add_alpha(that, &display->this);
+
+   /* This is only necessary if the alpha value is less than 1. */
+   if (that->alphaf < 1)
+   {
+      /* Now we do the background calculation without any gamma correction. */
+      if (that->alphaf <= 0)
+      {
+         that->redf = data.redf;
+         that->greenf = data.greenf;
+         that->bluef = data.bluef;
+
+         that->rede = data.rede;
+         that->greene = data.greene;
+         that->bluee = data.bluee;
+
+         that->red_sBIT= data.red_sBIT;
+         that->green_sBIT= data.green_sBIT;
+         that->blue_sBIT= data.blue_sBIT;
+      }
+
+      else /* 0 < alpha < 1 */
+      {
+         double alf = 1 - that->alphaf;
+
+         that->redf = that->redf * that->alphaf + data.redf * alf;
+         that->rede = that->rede * that->alphaf + data.rede * alf +
+            DBL_EPSILON;
+         that->greenf = that->greenf * that->alphaf + data.greenf * alf;
+         that->greene = that->greene * that->alphaf + data.greene * alf +
+            DBL_EPSILON;
+         that->bluef = that->bluef * that->alphaf + data.bluef * alf;
+         that->bluee = that->bluee * that->alphaf + data.bluee * alf +
+            DBL_EPSILON;
+      }
+
+      /* Remove the alpha type and set the alpha (not in that order.) */
+      that->alphaf = 1;
+      that->alphae = 0;
+
+      if (that->colour_type == PNG_COLOR_TYPE_RGB_ALPHA)
+         that->colour_type = PNG_COLOR_TYPE_RGB;
+      else if (that->colour_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+         that->colour_type = PNG_COLOR_TYPE_GRAY;
+      /* PNG_COLOR_TYPE_PALETTE is not changed */
+   }
+
+   this->next->mod(this->next, that, pp, display);
+}
+
+#define image_transform_png_set_background_add image_transform_default_add
+
+#undef data
+IT(background);
+#undef PT
+#define PT ITSTRUCT(background)
+#endif /* PNG_READ_BACKGROUND_SUPPORTED */
+
+/* This may just be 'end' if all the transforms are disabled! */
+static image_transform *PNG_CONST image_transform_first = &PT;
+
+static void
+transform_enable(PNG_CONST char *name)
+{
+   /* Everything starts out enabled, so if we see an 'enable' disabled
+    * everything else the first time round.
+    */
+   static int all_disabled = 0;
+   int found_it = 0;
+   image_transform *list = image_transform_first;
+
+   while (list != &image_transform_end)
+   {
+      if (strcmp(list->name, name) == 0)
+      {
+         list->enable = 1;
+         found_it = 1;
+      }
+      else if (!all_disabled)
+         list->enable = 0;
+
+      list = list->list;
+   }
+
+   all_disabled = 1;
+
+   if (!found_it)
+   {
+      fprintf(stderr, "pngvalid: --transform-enable=%s: unknown transform\n",
+         name);
+      exit(1);
+   }
+}
+
+static void
+transform_disable(PNG_CONST char *name)
+{
+   image_transform *list = image_transform_first;
+
+   while (list != &image_transform_end)
+   {
+      if (strcmp(list->name, name) == 0)
+      {
+         list->enable = 0;
+         return;
+      }
+
+      list = list->list;
+   }
+
+   fprintf(stderr, "pngvalid: --transform-disable=%s: unknown transform\n",
+      name);
+   exit(1);
+}
+
+static void
+image_transform_reset_count(void)
+{
+   image_transform *next = image_transform_first;
+   int count = 0;
+
+   while (next != &image_transform_end)
+   {
+      next->local_use = 0;
+      next->next = 0;
+      next = next->list;
+      ++count;
+   }
+
+   /* This can only happen if we every have more than 32 transforms (excluding
+    * the end) in the list.
+    */
+   if (count > 32) abort();
+}
+
+static int
+image_transform_test_counter(png_uint_32 counter, unsigned int max)
+{
+   /* Test the list to see if there is any point contining, given a current
+    * counter and a 'max' value.
+    */
+   image_transform *next = image_transform_first;
+
+   while (next != &image_transform_end)
+   {
+      /* For max 0 or 1 continue until the counter overflows: */
+      counter >>= 1;
+
+      /* Continue if any entry hasn't reacked the max. */
+      if (max > 1 && next->local_use < max)
+         return 1;
+      next = next->list;
+   }
+
+   return max <= 1 && counter == 0;
+}
+
+static png_uint_32
+image_transform_add(PNG_CONST image_transform **this, unsigned int max,
+   png_uint_32 counter, char *name, size_t sizeof_name, size_t *pos,
+   png_byte colour_type, png_byte bit_depth)
+{
+   for (;;) /* until we manage to add something */
+   {
+      png_uint_32 mask;
+      image_transform *list;
+
+      /* Find the next counter value, if the counter is zero this is the start
+       * of the list.  This routine always returns the current counter (not the
+       * next) so it returns 0 at the end and expects 0 at the beginning.
+       */
+      if (counter == 0) /* first time */
+      {
+         image_transform_reset_count();
+         if (max <= 1)
+            counter = 1;
+         else
+            counter = random_32();
+      }
+      else /* advance the counter */
+      {
+         switch (max)
+         {
+            case 0:  ++counter; break;
+            case 1:  counter <<= 1; break;
+            default: counter = random_32(); break;
+         }
+      }
+
+      /* Now add all these items, if possible */
+      *this = &image_transform_end;
+      list = image_transform_first;
+      mask = 1;
+
+      /* Go through the whole list adding anything that the counter selects: */
+      while (list != &image_transform_end)
+      {
+         if ((counter & mask) != 0 && list->enable &&
+             (max == 0 || list->local_use < max))
+         {
+            /* Candidate to add: */
+            if (list->add(list, this, colour_type, bit_depth) || max == 0)
+            {
+               /* Added, so add to the name too. */
+               *pos = safecat(name, sizeof_name, *pos, " +");
+               *pos = safecat(name, sizeof_name, *pos, list->name);
+            }
+
+            else
+            {
+               /* Not useful and max>0, so remove it from *this: */
+               *this = list->next;
+               list->next = 0;
+
+               /* And, since we know it isn't useful, stop it being added again
+                * in this run:
+                */
+               list->local_use = max;
+            }
+         }
+
+         mask <<= 1;
+         list = list->list;
+      }
+
+      /* Now if anything was added we have something to do. */
+      if (*this != &image_transform_end)
+         return counter;
+
+      /* Nothing added, but was there anything in there to add? */
+      if (!image_transform_test_counter(counter, max))
+         return 0;
+   }
+}
+
+#ifdef THIS_IS_THE_PROFORMA
+static void
+image_transform_png_set_@_set(PNG_CONST image_transform *this,
+    transform_display *that, png_structp pp, png_infop pi)
+{
+   png_set_@(pp);
+   this->next->set(this->next, that, pp, pi);
+}
+
+static void
+image_transform_png_set_@_mod(PNG_CONST image_transform *this,
+    image_pixel *that, png_structp pp, PNG_CONST transform_display *display)
+{
+   this->next->mod(this->next, that, pp, display);
+}
+
+static int
+image_transform_png_set_@_add(image_transform *this,
+    PNG_CONST image_transform **that, char *name, size_t sizeof_name,
+    size_t *pos, png_byte colour_type, png_byte bit_depth)
+{
+   this->next = *that;
+   *that = this;
+
+   *pos = safecat(name, sizeof_name, *pos, " +@");
+
+   return 1;
+}
+
+IT(@);
+#endif
+
+/* png_set_quantize(png_structp, png_colorp palette, int num_palette,
+ *    int maximum_colors, png_const_uint_16p histogram, int full_quantize)
+ *
+ * Very difficult to validate this!
+ */
+/*NOTE: TBD NYI */
+
+/* The data layout transforms are handled by swapping our own channel data,
+ * necessarily these need to happen at the end of the transform list because the
+ * semantic of the channels changes after these are executed.  Some of these,
+ * like set_shift and set_packing, can't be done at present because they change
+ * the layout of the data at the sub-sample level so sample() won't get the
+ * right answer.
+ */
+/* png_set_invert_alpha */
+/*NOTE: TBD NYI */
+
+/* png_set_bgr */
+/*NOTE: TBD NYI */
+
+/* png_set_swap_alpha */
+/*NOTE: TBD NYI */
+
+/* png_set_swap */
+/*NOTE: TBD NYI */
+
+/* png_set_filler, (png_structp png_ptr, png_uint_32 filler, int flags)); */
+/*NOTE: TBD NYI */
+
+/* png_set_add_alpha, (png_structp png_ptr, png_uint_32 filler, int flags)); */
+/*NOTE: TBD NYI */
+
+/* png_set_packing */
+/*NOTE: TBD NYI */
+
+/* png_set_packswap */
+/*NOTE: TBD NYI */
+
+/* png_set_invert_mono */
+/*NOTE: TBD NYI */
+
+/* png_set_shift(png_structp, png_const_color_8p true_bits) */
+/*NOTE: TBD NYI */
+
+static void
+perform_transform_test(png_modifier *pm)
+{
+   png_byte colour_type = 0;
+   png_byte bit_depth = 0;
+   int palette_number = 0;
+
+   while (next_format(&colour_type, &bit_depth, &palette_number))
+   {
+      png_uint_32 counter = 0;
+      size_t base_pos;
+      char name[64];
+
+      base_pos = safecat(name, sizeof name, 0, "transform:");
+
+      for (;;)
+      {
+         size_t pos = base_pos;
+         PNG_CONST image_transform *list = 0;
+
+         /* 'max' is currently hardwired to '1'; this should be settable on the
+          * command line.
+          */
+         counter = image_transform_add(&list, 1/*max*/, counter,
+            name, sizeof name, &pos, colour_type, bit_depth);
+
+         if (counter == 0)
+            break;
+
+         /* The command line can change this to checking interlaced images. */
+         do
+         {
+            pm->repeat = 0;
+            transform_test(pm, FILEID(colour_type, bit_depth, palette_number,
+               pm->interlace_type, 0, 0, 0), list, name);
+
+            if (fail(pm))
+               return;
+         }
+         while (pm->repeat);
+      }
+   }
+}
+#endif /* PNG_READ_TRANSFORMS_SUPPORTED */
+
+/********************************* GAMMA TESTS ********************************/
+#ifdef PNG_READ_GAMMA_SUPPORTED
+/* Reader callbacks and implementations, where they differ from the standard
+ * ones.
+ */
+typedef struct gamma_display
+{
+   standard_display this;
+
+   /* Parameters */
+   png_modifier*    pm;
+   double           file_gamma;
+   double           screen_gamma;
+   double           background_gamma;
+   png_byte         sbit;
+   int              threshold_test;
+   int              use_input_precision;
+   int              scale16;
+   int              expand16;
+   int              do_background;
+   png_color_16     background_color;
+
+   /* Local variables */
+   double       maxerrout;
+   double       maxerrpc;
+   double       maxerrabs;
+} gamma_display;
+
+#define ALPHA_MODE_OFFSET 4
+
+static void
+gamma_display_init(gamma_display *dp, png_modifier *pm, png_uint_32 id,
+    double file_gamma, double screen_gamma, png_byte sbit, int threshold_test,
+    int use_input_precision, int scale16, int expand16,
+    int do_background, PNG_CONST png_color_16 *pointer_to_the_background_color,
+    double background_gamma)
+{
+   /* Standard fields */
+   standard_display_init(&dp->this, &pm->this, id, 0/*do_interlace*/,
+      pm->use_update_info);
+
+   /* Parameter fields */
+   dp->pm = pm;
+   dp->file_gamma = file_gamma;
+   dp->screen_gamma = screen_gamma;
+   dp->background_gamma = background_gamma;
+   dp->sbit = sbit;
+   dp->threshold_test = threshold_test;
+   dp->use_input_precision = use_input_precision;
+   dp->scale16 = scale16;
+   dp->expand16 = expand16;
+   dp->do_background = do_background;
+   if (do_background && pointer_to_the_background_color != 0)
+      dp->background_color = *pointer_to_the_background_color;
+   else
+      memset(&dp->background_color, 0, sizeof dp->background_color);
+
+   /* Local variable fields */
+   dp->maxerrout = dp->maxerrpc = dp->maxerrabs = 0;
+}
+
+static void
+gamma_info_imp(gamma_display *dp, png_structp pp, png_infop pi)
+{
+   /* Reuse the standard stuff as appropriate. */
+   standard_info_part1(&dp->this, pp, pi);
+
+   /* If requested strip 16 to 8 bits - this is handled automagically below
+    * because the output bit depth is read from the library.  Note that there
+    * are interactions with sBIT but, internally, libpng makes sbit at most
+    * PNG_MAX_GAMMA_8 when doing the following.
+    */
+   if (dp->scale16)
+#     ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
+         png_set_scale_16(pp);
+#     else
+         /* The following works both in 1.5.4 and earlier versions: */
+#        ifdef PNG_READ_16_TO_8_SUPPORTED
+            png_set_strip_16(pp);
+#        else
+            png_error(pp, "scale16 (16 to 8 bit conversion) not supported");
+#        endif
+#     endif
+
+   if (dp->expand16)
+#     ifdef PNG_READ_EXPAND_16_SUPPORTED
+         png_set_expand_16(pp);
+#     else
+         png_error(pp, "expand16 (8 to 16 bit conversion) not supported");
+#     endif
+
+   if (dp->do_background >= ALPHA_MODE_OFFSET)
+   {
+#     ifdef PNG_READ_ALPHA_MODE_SUPPORTED
+      {
+         /* This tests the alpha mode handling, if supported. */
+         int mode = dp->do_background - ALPHA_MODE_OFFSET;
+
+         /* The gamma value is the output gamma, and is in the standard,
+          * non-inverted, represenation.  It provides a default for the PNG file
+          * gamma, but since the file has a gAMA chunk this does not matter.
+          */
+         PNG_CONST double sg = dp->screen_gamma;
+#        ifndef PNG_FLOATING_POINT_SUPPORTED
+            PNG_CONST png_fixed_point g = fix(sg);
+#        endif
+
+#        ifdef PNG_FLOATING_POINT_SUPPORTED
+            png_set_alpha_mode(pp, mode, sg);
+#        else
+            png_set_alpha_mode_fixed(pp, mode, g);
+#        endif
+
+         /* However, for the standard Porter-Duff algorithm the output defaults
+          * to be linear, so if the test requires non-linear output it must be
+          * corrected here.
+          */
+         if (mode == PNG_ALPHA_STANDARD && sg != 1)
+         {
+#           ifdef PNG_FLOATING_POINT_SUPPORTED
+               png_set_gamma(pp, sg, dp->file_gamma);
+#           else
+               png_fixed_point f = fix(dp->file_gamma);
+               png_set_gamma_fixed(pp, g, f);
+#           endif
+         }
+      }
+#     else
+         png_error(pp, "alpha mode handling not supported");
+#     endif
+   }
+
+   else
+   {
+      /* Set up gamma processing. */
+#     ifdef PNG_FLOATING_POINT_SUPPORTED
+         png_set_gamma(pp, dp->screen_gamma, dp->file_gamma);
+#     else
+      {
+         png_fixed_point s = fix(dp->screen_gamma);
+         png_fixed_point f = fix(dp->file_gamma);
+         png_set_gamma_fixed(pp, s, f);
+      }
+#     endif
+
+      if (dp->do_background)
+      {
+#     ifdef PNG_READ_BACKGROUND_SUPPORTED
+         /* NOTE: this assumes the caller provided the correct background gamma!
+          */
+         PNG_CONST double bg = dp->background_gamma;
+#        ifndef PNG_FLOATING_POINT_SUPPORTED
+            PNG_CONST png_fixed_point g = fix(bg);
+#        endif
+
+#        ifdef PNG_FLOATING_POINT_SUPPORTED
+            png_set_background(pp, &dp->background_color, dp->do_background,
+               0/*need_expand*/, bg);
+#        else
+            png_set_background_fixed(pp, &dp->background_color,
+               dp->do_background, 0/*need_expand*/, g);
+#        endif
+#     else
+         png_error(pp, "png_set_background not supported");
+#     endif
+      }
+   }
+
+   {
+      int i = dp->this.use_update_info;
+      /* Always do one call, even if use_update_info is 0. */
+      do
+         png_read_update_info(pp, pi);
+      while (--i > 0);
+   }
+
+   /* Now we may get a different cbRow: */
+   standard_info_part2(&dp->this, pp, pi, 1 /*images*/);
+}
+
+static void
+gamma_info(png_structp pp, png_infop pi)
+{
+   gamma_info_imp(voidcast(gamma_display*, png_get_progressive_ptr(pp)), pp,
+      pi);
+}
+
+/* Validate a single component value - the routine gets the input and output
+ * sample values as unscaled PNG component values along with a cache of all the
+ * information required to validate the values.
+ */
+typedef struct validate_info
+{
+   png_structp  pp;
+   gamma_display *dp;
+   png_byte sbit;
+   int use_input_precision;
+   int do_background;
+   int scale16;
+   unsigned int sbit_max;
+   unsigned int isbit_shift;
+   unsigned int outmax;
+
+   double gamma_correction; /* Overall correction required. */
+   double file_inverse;     /* Inverse of file gamma. */
+   double screen_gamma;
+   double screen_inverse;   /* Inverse of screen gamma. */
+
+   double background_red;   /* Linear background value, red or gray. */
+   double background_green;
+   double background_blue;
+
+   double maxabs;
+   double maxpc;
+   double maxcalc;
+   double maxout;
+   double maxout_total;     /* Total including quantization error */
+   double outlog;
+   int    outquant;
+}
+validate_info;
+
+static void
+init_validate_info(validate_info *vi, gamma_display *dp, png_struct *pp,
+    int in_depth, int out_depth)
+{
+   PNG_CONST unsigned int outmax = (1U<<out_depth)-1;
+
+   vi->pp = pp;
+   vi->dp = dp;
+
+   if (dp->sbit > 0 && dp->sbit < in_depth)
+   {
+      vi->sbit = dp->sbit;
+      vi->isbit_shift = in_depth - dp->sbit;
+   }
+
+   else
+   {
+      vi->sbit = (png_byte)in_depth;
+      vi->isbit_shift = 0;
+   }
+
+   vi->sbit_max = (1U << vi->sbit)-1;
+
+   /* This mimics the libpng threshold test, '0' is used to prevent gamma
+    * correction in the validation test.
+    */
+   vi->screen_gamma = dp->screen_gamma;
+   if (fabs(vi->screen_gamma-1) < PNG_GAMMA_THRESHOLD)
+      vi->screen_gamma = vi->screen_inverse = 0;
+   else
+      vi->screen_inverse = 1/vi->screen_gamma;
+
+   vi->use_input_precision = dp->use_input_precision;
+   vi->outmax = outmax;
+   vi->maxabs = abserr(dp->pm, in_depth, out_depth);
+   vi->maxpc = pcerr(dp->pm, in_depth, out_depth);
+   vi->maxcalc = calcerr(dp->pm, in_depth, out_depth);
+   vi->maxout = outerr(dp->pm, in_depth, out_depth);
+   vi->outquant = output_quantization_factor(dp->pm, in_depth, out_depth);
+   vi->maxout_total = vi->maxout + vi->outquant * .5;
+   vi->outlog = outlog(dp->pm, in_depth, out_depth);
+
+   if ((dp->this.colour_type & PNG_COLOR_MASK_ALPHA) != 0 ||
+      (dp->this.colour_type == 3 && dp->this.is_transparent))
+   {
+      vi->do_background = dp->do_background;
+
+      if (vi->do_background != 0)
+      {
+         PNG_CONST double bg_inverse = 1/dp->background_gamma;
+         double r, g, b;
+
+         /* Caller must at least put the gray value into the red channel */
+         r = dp->background_color.red; r /= outmax;
+         g = dp->background_color.green; g /= outmax;
+         b = dp->background_color.blue; b /= outmax;
+
+#     if 0
+         /* libpng doesn't do this optimization, if we do pngvalid will fail.
+          */
+         if (fabs(bg_inverse-1) >= PNG_GAMMA_THRESHOLD)
+#     endif
+         {
+            r = pow(r, bg_inverse);
+            g = pow(g, bg_inverse);
+            b = pow(b, bg_inverse);
+         }
+
+         vi->background_red = r;
+         vi->background_green = g;
+         vi->background_blue = b;
+      }
+   }
+   else
+      vi->do_background = 0;
+
+   if (vi->do_background == 0)
+      vi->background_red = vi->background_green = vi->background_blue = 0;
+
+   vi->gamma_correction = 1/(dp->file_gamma*dp->screen_gamma);
+   if (fabs(vi->gamma_correction-1) < PNG_GAMMA_THRESHOLD)
+      vi->gamma_correction = 0;
+
+   vi->file_inverse = 1/dp->file_gamma;
+   if (fabs(vi->file_inverse-1) < PNG_GAMMA_THRESHOLD)
+      vi->file_inverse = 0;
+
+   vi->scale16 = dp->scale16;
+}
+
+/* This function handles composition of a single non-alpha component.  The
+ * argument is the input sample value, in the range 0..1, and the alpha value.
+ * The result is the composed, linear, input sample.  If alpha is less than zero
+ * this is the alpha component and the function should not be called!
+ */
+static double
+gamma_component_compose(int do_background, double input_sample, double alpha,
+   double background, int *compose)
+{
+   switch (do_background)
+   {
+      case PNG_BACKGROUND_GAMMA_SCREEN:
+      case PNG_BACKGROUND_GAMMA_FILE:
+      case PNG_BACKGROUND_GAMMA_UNIQUE:
+         /* Standard PNG background processing. */
+         if (alpha < 1)
+         {
+            if (alpha > 0)
+            {
+               input_sample = input_sample * alpha + background * (1-alpha);
+               if (compose != NULL)
+                  *compose = 1;
+            }
+
+            else
+               input_sample = background;
+         }
+         break;
+
+#ifdef PNG_READ_ALPHA_MODE_SUPPORTED
+      case ALPHA_MODE_OFFSET + PNG_ALPHA_STANDARD:
+      case ALPHA_MODE_OFFSET + PNG_ALPHA_BROKEN:
+         /* The components are premultiplied in either case and the output is
+          * gamma encoded (to get standard Porter-Duff we expect the output
+          * gamma to be set to 1.0!)
+          */
+      case ALPHA_MODE_OFFSET + PNG_ALPHA_OPTIMIZED:
+         /* The optimization is that the partial-alpha entries are linear
+          * while the opaque pixels are gamma encoded, but this only affects the
+          * output encoding.
+          */
+         if (alpha < 1)
+         {
+            if (alpha > 0)
+            {
+               input_sample *= alpha;
+               if (compose != NULL)
+                  *compose = 1;
+            }
+
+            else
+               input_sample = 0;
+         }
+         break;
+#endif
+
+      default:
+         /* Standard cases where no compositing is done (so the component
+          * value is already correct.)
+          */
+         break;
+   }
+
+   return input_sample;
+}
+
+/* This API returns the encoded *input* component, in the range 0..1 */
+static double
+gamma_component_validate(PNG_CONST char *name, PNG_CONST validate_info *vi,
+    PNG_CONST unsigned int id, PNG_CONST unsigned int od,
+    PNG_CONST double alpha /* <0 for the alpha channel itself */,
+    PNG_CONST double background /* component background value */)
+{
+   PNG_CONST unsigned int isbit = id >> vi->isbit_shift;
+   PNG_CONST unsigned int sbit_max = vi->sbit_max;
+   PNG_CONST unsigned int outmax = vi->outmax;
+   PNG_CONST int do_background = vi->do_background;
+
+   double i;
+
+   /* First check on the 'perfect' result obtained from the digitized input
+    * value, id, and compare this against the actual digitized result, 'od'.
+    * 'i' is the input result in the range 0..1:
+    */
+   i = isbit; i /= sbit_max;
+
+   /* Check for the fast route: if we don't do any background composition or if
+    * this is the alpha channel ('alpha' < 0) or if the pixel is opaque then
+    * just use the gamma_correction field to correct to the final output gamma.
+    */
+   if (alpha == 1 /* opaque pixel component */ || !do_background
+#ifdef PNG_READ_ALPHA_MODE_SUPPORTED
+      || do_background == ALPHA_MODE_OFFSET + PNG_ALPHA_PNG
+#endif
+      || (alpha < 0 /* alpha channel */
+#ifdef PNG_READ_ALPHA_MODE_SUPPORTED
+      && do_background != ALPHA_MODE_OFFSET + PNG_ALPHA_BROKEN
+#endif
+      ))
+   {
+      /* Then get the gamma corrected version of 'i' and compare to 'od', any
+       * error less than .5 is insignificant - just quantization of the output
+       * value to the nearest digital value (nevertheless the error is still
+       * recorded - it's interesting ;-)
+       */
+      double encoded_sample = i;
+      double encoded_error;
+
+      /* alpha less than 0 indicates the alpha channel, which is always linear
+       */
+      if (alpha >= 0 && vi->gamma_correction > 0)
+         encoded_sample = pow(encoded_sample, vi->gamma_correction);
+      encoded_sample *= outmax;
+
+      encoded_error = fabs(od-encoded_sample);
+
+      if (encoded_error > vi->dp->maxerrout)
+         vi->dp->maxerrout = encoded_error;
+
+      if (encoded_error < vi->maxout_total && encoded_error < vi->outlog)
+         return i;
+   }
+
+   /* The slow route - attempt to do linear calculations. */
+   /* There may be an error, or background processing is required, so calculate
+    * the actual sample values - unencoded light intensity values.  Note that in
+    * practice these are not completely unencoded because they include a
+    * 'viewing correction' to decrease or (normally) increase the perceptual
+    * contrast of the image.  There's nothing we can do about this - we don't
+    * know what it is - so assume the unencoded value is perceptually linear.
+    */
+   {
+      double input_sample = i; /* In range 0..1 */
+      double output, error, encoded_sample, encoded_error;
+      double es_lo, es_hi;
+      int compose = 0;           /* Set to one if composition done */
+      int output_is_encoded;     /* Set if encoded to screen gamma */
+      int log_max_error = 1;     /* Check maximum error values */
+      png_const_charp pass = 0;  /* Reason test passes (or 0 for fail) */
+
+      /* Convert to linear light (with the above caveat.)  The alpha channel is
+       * already linear.
+       */
+      if (alpha >= 0)
+      {
+         int tcompose;
+
+         if (vi->file_inverse > 0)
+            input_sample = pow(input_sample, vi->file_inverse);
+
+         /* Handle the compose processing: */
+         tcompose = 0;
+         input_sample = gamma_component_compose(do_background, input_sample,
+            alpha, background, &tcompose);
+
+         if (tcompose)
+            compose = 1;
+      }
+
+      /* And similarly for the output value, but we need to check the background
+       * handling to linearize it correctly.
+       */
+      output = od;
+      output /= outmax;
+
+      output_is_encoded = vi->screen_gamma > 0;
+
+      if (alpha < 0) /* The alpha channel */
+      {
+#ifdef PNG_READ_ALPHA_MODE_SUPPORTED
+         if (do_background != ALPHA_MODE_OFFSET + PNG_ALPHA_BROKEN)
+#endif
+         {
+            /* In all other cases the output alpha channel is linear already,
+             * don't log errors here, they are much larger in linear data.
+             */
+            output_is_encoded = 0;
+            log_max_error = 0;
+         }
+      }
+
+#ifdef PNG_READ_ALPHA_MODE_SUPPORTED
+      else /* A component */
+      {
+         if (do_background == ALPHA_MODE_OFFSET + PNG_ALPHA_OPTIMIZED &&
+            alpha < 1) /* the optimized case - linear output */
+         {
+            if (alpha > 0) log_max_error = 0;
+            output_is_encoded = 0;
+         }
+      }
+#endif
+
+      if (output_is_encoded)
+         output = pow(output, vi->screen_gamma);
+
+      /* Calculate (or recalculate) the encoded_sample value and repeat the
+       * check above (unnecessary if we took the fast route, but harmless.)
+       */
+      encoded_sample = input_sample;
+      if (output_is_encoded)
+         encoded_sample = pow(encoded_sample, vi->screen_inverse);
+      encoded_sample *= outmax;
+
+      encoded_error = fabs(od-encoded_sample);
+
+      /* Don't log errors in the alpha channel, or the 'optimized' case,
+       * neither are significant to the overall perception.
+       */
+      if (log_max_error && encoded_error > vi->dp->maxerrout)
+         vi->dp->maxerrout = encoded_error;
+
+      if (encoded_error < vi->maxout_total)
+      {
+         if (encoded_error < vi->outlog)
+            return i;
+
+         /* Test passed but error is bigger than the log limit, record why the
+          * test passed:
+          */
+         pass = "less than maxout:\n";
+      }
+
+      /* i: the original input value in the range 0..1
+       *
+       * pngvalid calculations:
+       *  input_sample: linear result; i linearized and composed, range 0..1
+       *  encoded_sample: encoded result; input_sample scaled to ouput bit depth
+       *
+       * libpng calculations:
+       *  output: linear result; od scaled to 0..1 and linearized
+       *  od: encoded result from libpng
+       */
+
+      /* Now we have the numbers for real errors, both absolute values as as a
+       * percentage of the correct value (output):
+       */
+      error = fabs(input_sample-output);
+
+      if (log_max_error && error > vi->dp->maxerrabs)
+         vi->dp->maxerrabs = error;
+
+      /* The following is an attempt to ignore the tendency of quantization to
+       * dominate the percentage errors for lower result values:
+       */
+      if (log_max_error && input_sample > .5)
+      {
+         double percentage_error = error/input_sample;
+         if (percentage_error > vi->dp->maxerrpc)
+            vi->dp->maxerrpc = percentage_error;
+      }
+
+      /* Now calculate the digitization limits for 'encoded_sample' using the
+       * 'max' values.  Note that maxout is in the encoded space but maxpc and
+       * maxabs are in linear light space.
+       *
+       * First find the maximum error in linear light space, range 0..1:
+       */
+      {
+         double tmp = input_sample * vi->maxpc;
+         if (tmp < vi->maxabs) tmp = vi->maxabs;
+         /* If 'compose' is true the composition was done in linear space using
+          * integer arithmetic.  This introduces an extra error of +/- 0.5 (at
+          * least) in the integer space used.  'maxcalc' records this, taking
+          * into account the possibility that even for 16 bit output 8 bit space
+          * may have been used.
+          */
+         if (compose && tmp < vi->maxcalc) tmp = vi->maxcalc;
+
+         /* The 'maxout' value refers to the encoded result, to compare with
+          * this encode input_sample adjusted by the maximum error (tmp) above.
+          */
+         es_lo = encoded_sample - vi->maxout;
+
+         if (es_lo > 0 && input_sample-tmp > 0)
+         {
+            double low_value = input_sample-tmp;
+            if (output_is_encoded)
+               low_value = pow(low_value, vi->screen_inverse);
+            low_value *= outmax;
+            if (low_value < es_lo) es_lo = low_value;
+
+            /* Quantize this appropriately: */
+            es_lo = ceil(es_lo / vi->outquant - .5) * vi->outquant;
+         }
+
+         else
+            es_lo = 0;
+
+         es_hi = encoded_sample + vi->maxout;
+
+         if (es_hi < outmax && input_sample+tmp < 1)
+         {
+            double high_value = input_sample+tmp;
+            if (output_is_encoded)
+               high_value = pow(high_value, vi->screen_inverse);
+            high_value *= outmax;
+            if (high_value > es_hi) es_hi = high_value;
+
+            es_hi = floor(es_hi / vi->outquant + .5) * vi->outquant;
+         }
+
+         else
+            es_hi = outmax;
+      }
+
+      /* The primary test is that the final encoded value returned by the
+       * library should be between the two limits (inclusive) that were
+       * calculated above.
+       */
+      if (od >= es_lo && od <= es_hi)
+      {
+         /* The value passes, but we may need to log the information anyway. */
+         if (encoded_error < vi->outlog)
+            return i;
+
+         if (pass == 0)
+            pass = "within digitization limits:\n";
+      }
+
+      {
+         /* There has been an error in processing, or we need to log this
+          * value.
+          */
+         double is_lo, is_hi;
+
+         /* pass is set at this point if either of the tests above would have
+          * passed.  Don't do these additional tests here - just log the
+          * original [es_lo..es_hi] values.
+          */
+         if (pass == 0 && vi->use_input_precision)
+         {
+            /* Ok, something is wrong - this actually happens in current libpng
+             * 16-to-8 processing.  Assume that the input value (id, adjusted
+             * for sbit) can be anywhere between value-.5 and value+.5 - quite a
+             * large range if sbit is low.
+             */
+            double tmp = (isbit - .5)/sbit_max;
+
+            if (tmp <= 0)
+               tmp = 0;
+
+            else if (alpha >= 0 && vi->file_inverse > 0 && tmp < 1)
+               tmp = pow(tmp, vi->file_inverse);
+
+            tmp = gamma_component_compose(do_background, tmp, alpha, background,
+               NULL);
+
+            if (output_is_encoded && tmp > 0 && tmp < 1)
+               tmp = pow(tmp, vi->screen_inverse);
+
+            is_lo = ceil(outmax * tmp - vi->maxout_total);
+
+            if (is_lo < 0)
+               is_lo = 0;
+
+            tmp = (isbit + .5)/sbit_max;
+
+            if (tmp <= 0)
+               tmp = 0;
+
+            else if (alpha >= 0 && vi->file_inverse > 0 && tmp < 1)
+               tmp = pow(tmp, vi->file_inverse);
+
+            tmp = gamma_component_compose(do_background, tmp, alpha, background,
+               NULL);
+
+            if (output_is_encoded && tmp > 0 && tmp < 1)
+               tmp = pow(tmp, vi->screen_inverse);
+
+            is_hi = floor(outmax * tmp + vi->maxout_total);
+
+            if (is_hi > outmax)
+               is_hi = outmax;
+
+            if (!(od < is_lo || od > is_hi))
+            {
+               if (encoded_error < vi->outlog)
+                  return i;
+
+               pass = "within input precision limits:\n";
+            }
+
+            /* One last chance.  If this is an alpha channel and the 16to8
+             * option has been used and 'inaccurate' scaling is used then the
+             * bit reduction is obtained by simply using the top 8 bits of the
+             * value.
+             *
+             * This is only done for older libpng versions when the 'inaccurate'
+             * (chop) method of scaling was used.
+             */
+#           ifndef PNG_READ_16_TO_8_ACCURATE_SCALE_SUPPORTED
+#              if PNG_LIBPNG_VER < 10504
+                  /* This may be required for other components in the future,
+                   * but at present the presence of gamma correction effectively
+                   * prevents the errors in the component scaling (I don't quite
+                   * understand why, but since it's better this way I care not
+                   * to ask, JB 20110419.)
+                   */
+                  if (pass == 0 && alpha < 0 && vi->scale16 && vi->sbit > 8 &&
+                     vi->sbit + vi->isbit_shift == 16)
+                  {
+                     tmp = ((id >> 8) - .5)/255;
+
+                     if (tmp > 0)
+                     {
+                        is_lo = ceil(outmax * tmp - vi->maxout_total);
+                        if (is_lo < 0) is_lo = 0;
+                     }
+
+                     else
+                        is_lo = 0;
+
+                     tmp = ((id >> 8) + .5)/255;
+
+                     if (tmp < 1)
+                     {
+                        is_hi = floor(outmax * tmp + vi->maxout_total);
+                        if (is_hi > outmax) is_hi = outmax;
+                     }
+
+                     else
+                        is_hi = outmax;
+
+                     if (!(od < is_lo || od > is_hi))
+                     {
+                        if (encoded_error < vi->outlog)
+                           return i;
+
+                        pass = "within 8 bit limits:\n";
+                     }
+                  }
+#              endif
+#           endif
+         }
+         else /* !use_input_precision */
+            is_lo = es_lo, is_hi = es_hi;
+
+         /* Attempt to output a meaningful error/warning message: the message
+          * output depends on the background/composite operation being performed
+          * because this changes what parameters were actually used above.
+          */
+         {
+            size_t pos = 0;
+            /* Need either 1/255 or 1/65535 precision here; 3 or 6 decimal
+             * places.  Just use outmax to work out which.
+             */
+            int precision = (outmax >= 1000 ? 6 : 3);
+            int use_input=1, use_background=0, do_compose=0;
+            char msg[256];
+
+            if (pass != 0)
+               pos = safecat(msg, sizeof msg, pos, "\n\t");
+
+            /* Set up the various flags, the output_is_encoded flag above
+             * is also used below.  do_compose is just a double check.
+             */
+            switch (do_background)
+            {
+            case PNG_BACKGROUND_GAMMA_SCREEN:
+            case PNG_BACKGROUND_GAMMA_FILE:
+            case PNG_BACKGROUND_GAMMA_UNIQUE:
+               use_background = (alpha >= 0 && alpha < 1);
+               /*FALL THROUGH*/
+#           ifdef PNG_READ_ALPHA_MODE_SUPPORTED
+               case ALPHA_MODE_OFFSET + PNG_ALPHA_STANDARD:
+               case ALPHA_MODE_OFFSET + PNG_ALPHA_BROKEN:
+               case ALPHA_MODE_OFFSET + PNG_ALPHA_OPTIMIZED:
+#           endif /* ALPHA_MODE_SUPPORTED */
+               do_compose = (alpha > 0 && alpha < 1);
+               use_input = (alpha != 0);
+               break;
+
+            default:
+               break;
+            }
+
+            /* Check the 'compose' flag */
+            if (compose != do_compose)
+               png_error(vi->pp, "internal error (compose)");
+
+            /* 'name' is the component name */
+            pos = safecat(msg, sizeof msg, pos, name);
+            pos = safecat(msg, sizeof msg, pos, "(");
+            pos = safecatn(msg, sizeof msg, pos, id);
+            if (use_input || pass != 0/*logging*/)
+            {
+               if (isbit != id)
+               {
+                  /* sBIT has reduced the precision of the input: */
+                  pos = safecat(msg, sizeof msg, pos, ", sbit(");
+                  pos = safecatn(msg, sizeof msg, pos, vi->sbit);
+                  pos = safecat(msg, sizeof msg, pos, "): ");
+                  pos = safecatn(msg, sizeof msg, pos, isbit);
+               }
+               pos = safecat(msg, sizeof msg, pos, "/");
+               /* The output is either "id/max" or "id sbit(sbit): isbit/max" */
+               pos = safecatn(msg, sizeof msg, pos, vi->sbit_max);
+            }
+            pos = safecat(msg, sizeof msg, pos, ")");
+
+            /* A component may have been multiplied (in linear space) by the
+             * alpha value, 'compose' says whether this is relevant.
+             */
+            if (compose || pass != 0)
+            {
+               /* If any form of composition is being done report our
+                * calculated linear value here (the code above doesn't record
+                * the input value before composition is performed, so what
+                * gets reported is the value after composition.)
+                */
+               if (use_input || pass != 0)
+               {
+                  if (vi->file_inverse > 0)
+                  {
+                     pos = safecat(msg, sizeof msg, pos, "^");
+                     pos = safecatd(msg, sizeof msg, pos, vi->file_inverse, 2);
+                  }
+
+                  else
+                     pos = safecat(msg, sizeof msg, pos, "[linear]");
+
+                  pos = safecat(msg, sizeof msg, pos, "*(alpha)");
+                  pos = safecatd(msg, sizeof msg, pos, alpha, precision);
+               }
+
+               /* Now record the *linear* background value if it was used
+                * (this function is not passed the original, non-linear,
+                * value but it is contained in the test name.)
+                */
+               if (use_background)
+               {
+                  pos = safecat(msg, sizeof msg, pos, use_input ? "+" : " ");
+                  pos = safecat(msg, sizeof msg, pos, "(background)");
+                  pos = safecatd(msg, sizeof msg, pos, background, precision);
+                  pos = safecat(msg, sizeof msg, pos, "*");
+                  pos = safecatd(msg, sizeof msg, pos, 1-alpha, precision);
+               }
+            }
+
+            /* Report the calculated value (input_sample) and the linearized
+             * libpng value (output) unless this is just a component gamma
+             * correction.
+             */
+            if (compose || alpha < 0 || pass != 0)
+            {
+               pos = safecat(msg, sizeof msg, pos,
+                  pass != 0 ? " =\n\t" : " = ");
+               pos = safecatd(msg, sizeof msg, pos, input_sample, precision);
+               pos = safecat(msg, sizeof msg, pos, " (libpng: ");
+               pos = safecatd(msg, sizeof msg, pos, output, precision);
+               pos = safecat(msg, sizeof msg, pos, ")");
+
+               /* Finally report the output gamma encoding, if any. */
+               if (output_is_encoded)
+               {
+                  pos = safecat(msg, sizeof msg, pos, " ^");
+                  pos = safecatd(msg, sizeof msg, pos, vi->screen_inverse, 2);
+                  pos = safecat(msg, sizeof msg, pos, "(to screen) =");
+               }
+
+               else
+                  pos = safecat(msg, sizeof msg, pos, " [screen is linear] =");
+            }
+
+            if ((!compose && alpha >= 0) || pass != 0)
+            {
+               if (pass != 0) /* logging */
+                  pos = safecat(msg, sizeof msg, pos, "\n\t[overall:");
+
+               /* This is the non-composition case, the internal linear
+                * values are irrelevant (though the log below will reveal
+                * them.)  Output a much shorter warning/error message and report
+                * the overall gamma correction.
+                */
+               if (vi->gamma_correction > 0)
+               {
+                  pos = safecat(msg, sizeof msg, pos, " ^");
+                  pos = safecatd(msg, sizeof msg, pos, vi->gamma_correction, 2);
+                  pos = safecat(msg, sizeof msg, pos, "(gamma correction) =");
+               }
+
+               else
+                  pos = safecat(msg, sizeof msg, pos,
+                     " [no gamma correction] =");
+
+               if (pass != 0)
+                  pos = safecat(msg, sizeof msg, pos, "]");
+            }
+
+            /* This is our calculated encoded_sample which should (but does
+             * not) match od:
+             */
+            pos = safecat(msg, sizeof msg, pos, pass != 0 ? "\n\t" : " ");
+            pos = safecatd(msg, sizeof msg, pos, is_lo, 1);
+            pos = safecat(msg, sizeof msg, pos, " < ");
+            pos = safecatd(msg, sizeof msg, pos, encoded_sample, 1);
+            pos = safecat(msg, sizeof msg, pos, " (libpng: ");
+            pos = safecatn(msg, sizeof msg, pos, od);
+            pos = safecat(msg, sizeof msg, pos, ")");
+            pos = safecat(msg, sizeof msg, pos, "/");
+            pos = safecatn(msg, sizeof msg, pos, outmax);
+            pos = safecat(msg, sizeof msg, pos, " < ");
+            pos = safecatd(msg, sizeof msg, pos, is_hi, 1);
+
+            if (pass == 0) /* The error condition */
+            {
+#              ifdef PNG_WARNINGS_SUPPORTED
+                  png_warning(vi->pp, msg);
+#              else
+                  store_warning(vi->pp, msg);
+#              endif
+            }
+
+            else /* logging this value */
+               store_verbose(&vi->dp->pm->this, vi->pp, pass, msg);
+         }
+      }
+   }
+
+   return i;
+}
+
+static void
+gamma_image_validate(gamma_display *dp, png_structp pp, png_infop pi)
+{
+   /* Get some constants derived from the input and output file formats: */
+   PNG_CONST png_store* PNG_CONST ps = dp->this.ps;
+   PNG_CONST png_byte in_ct = dp->this.colour_type;
+   PNG_CONST png_byte in_bd = dp->this.bit_depth;
+   PNG_CONST png_uint_32 w = dp->this.w;
+   PNG_CONST png_uint_32 h = dp->this.h;
+   PNG_CONST size_t cbRow = dp->this.cbRow;
+   PNG_CONST png_byte out_ct = png_get_color_type(pp, pi);
+   PNG_CONST png_byte out_bd = png_get_bit_depth(pp, pi);
+
+   /* There are three sources of error, firstly the quantization in the
+    * file encoding, determined by sbit and/or the file depth, secondly
+    * the output (screen) gamma and thirdly the output file encoding.
+    *
+    * Since this API receives the screen and file gamma in double
+    * precision it is possible to calculate an exact answer given an input
+    * pixel value.  Therefore we assume that the *input* value is exact -
+    * sample/maxsample - calculate the corresponding gamma corrected
+    * output to the limits of double precision arithmetic and compare with
+    * what libpng returns.
+    *
+    * Since the library must quantize the output to 8 or 16 bits there is
+    * a fundamental limit on the accuracy of the output of +/-.5 - this
+    * quantization limit is included in addition to the other limits
+    * specified by the paramaters to the API.  (Effectively, add .5
+    * everywhere.)
+    *
+    * The behavior of the 'sbit' paramter is defined by section 12.5
+    * (sample depth scaling) of the PNG spec.  That section forces the
+    * decoder to assume that the PNG values have been scaled if sBIT is
+    * present:
+    *
+    *     png-sample = floor( input-sample * (max-out/max-in) + .5);
+    *
+    * This means that only a subset of the possible PNG values should
+    * appear in the input. However, the spec allows the encoder to use a
+    * variety of approximations to the above and doesn't require any
+    * restriction of the values produced.
+    *
+    * Nevertheless the spec requires that the upper 'sBIT' bits of the
+    * value stored in a PNG file be the original sample bits.
+    * Consequently the code below simply scales the top sbit bits by
+    * (1<<sbit)-1 to obtain an original sample value.
+    *
+    * Because there is limited precision in the input it is arguable that
+    * an acceptable result is any valid result from input-.5 to input+.5.
+    * The basic tests below do not do this, however if 'use_input_precision'
+    * is set a subsequent test is performed below.
+    */
+   PNG_CONST unsigned int samples_per_pixel = (out_ct & 2U) ? 3U : 1U;
+   int processing;
+   png_uint_32 y;
+   PNG_CONST store_palette_entry *in_palette = dp->this.palette;
+   PNG_CONST int in_is_transparent = dp->this.is_transparent;
+   int out_npalette = -1;
+   int out_is_transparent = 0; /* Just refers to the palette case */
+   store_palette out_palette;
+   validate_info vi;
+
+   /* Check for row overwrite errors */
+   store_image_check(dp->this.ps, pp, 0);
+
+   /* Supply the input and output sample depths here - 8 for an indexed image,
+    * otherwise the bit depth.
+    */
+   init_validate_info(&vi, dp, pp, in_ct==3?8:in_bd, out_ct==3?8:out_bd);
+
+   processing = (vi.gamma_correction > 0 && !dp->threshold_test)
+      || in_bd != out_bd || in_ct != out_ct || vi.do_background;
+
+   /* TODO: FIX THIS: MAJOR BUG!  If the transformations all happen inside
+    * the palette there is no way of finding out, because libpng fails to
+    * update the palette on png_read_update_info.  Indeed, libpng doesn't
+    * even do the required work until much later, when it doesn't have any
+    * info pointer.  Oops.  For the moment 'processing' is turned off if
+    * out_ct is palette.
+    */
+   if (in_ct == 3 && out_ct == 3)
+      processing = 0;
+
+   if (processing && out_ct == 3)
+      out_is_transparent = read_palette(out_palette, &out_npalette, pp, pi);
+
+   for (y=0; y<h; ++y)
+   {
+      png_const_bytep pRow = store_image_row(ps, pp, 0, y);
+      png_byte std[STANDARD_ROWMAX];
+
+      transform_row(pp, std, in_ct, in_bd, y);
+
+      if (processing)
+      {
+         unsigned int x;
+
+         for (x=0; x<w; ++x)
+         {
+            double alpha = 1; /* serves as a flag value */
+
+            /* Record the palette index for index images. */
+            PNG_CONST unsigned int in_index =
+               in_ct == 3 ? sample(std, 3, in_bd, x, 0) : 256;
+            PNG_CONST unsigned int out_index =
+               out_ct == 3 ? sample(std, 3, out_bd, x, 0) : 256;
+
+            /* Handle input alpha - png_set_background will cause the output
+             * alpha to disappear so there is nothing to check.
+             */
+            if ((in_ct & PNG_COLOR_MASK_ALPHA) != 0 || (in_ct == 3 &&
+               in_is_transparent))
+            {
+               PNG_CONST unsigned int input_alpha = in_ct == 3 ?
+                  dp->this.palette[in_index].alpha :
+                  sample(std, in_ct, in_bd, x, samples_per_pixel);
+
+               unsigned int output_alpha = 65536 /* as a flag value */;
+
+               if (out_ct == 3)
+               {
+                  if (out_is_transparent)
+                     output_alpha = out_palette[out_index].alpha;
+               }
+
+               else if ((out_ct & PNG_COLOR_MASK_ALPHA) != 0)
+                  output_alpha = sample(pRow, out_ct, out_bd, x,
+                     samples_per_pixel);
+
+               if (output_alpha != 65536)
+                  alpha = gamma_component_validate("alpha", &vi, input_alpha,
+                     output_alpha, -1/*alpha*/, 0/*background*/);
+
+               else /* no alpha in output */
+               {
+                  /* This is a copy of the calculation of 'i' above in order to
+                   * have the alpha value to use in the background calculation.
+                   */
+                  alpha = input_alpha >> vi.isbit_shift;
+                  alpha /= vi.sbit_max;
+               }
+            }
+
+            /* Handle grayscale or RGB components. */
+            if ((in_ct & PNG_COLOR_MASK_COLOR) == 0) /* grayscale */
+               (void)gamma_component_validate("gray", &vi,
+                  sample(std, in_ct, in_bd, x, 0),
+                  sample(pRow, out_ct, out_bd, x, 0), alpha/*component*/,
+                  vi.background_red);
+            else /* RGB or palette */
+            {
+               (void)gamma_component_validate("red", &vi,
+                  in_ct == 3 ? in_palette[in_index].red :
+                     sample(std, in_ct, in_bd, x, 0),
+                  out_ct == 3 ? out_palette[out_index].red :
+                     sample(pRow, out_ct, out_bd, x, 0),
+                  alpha/*component*/, vi.background_red);
+
+               (void)gamma_component_validate("green", &vi,
+                  in_ct == 3 ? in_palette[in_index].green :
+                     sample(std, in_ct, in_bd, x, 1),
+                  out_ct == 3 ? out_palette[out_index].green :
+                     sample(pRow, out_ct, out_bd, x, 1),
+                  alpha/*component*/, vi.background_green);
+
+               (void)gamma_component_validate("blue", &vi,
+                  in_ct == 3 ? in_palette[in_index].blue :
+                     sample(std, in_ct, in_bd, x, 2),
+                  out_ct == 3 ? out_palette[out_index].blue :
+                     sample(pRow, out_ct, out_bd, x, 2),
+                  alpha/*component*/, vi.background_blue);
+            }
+         }
+      }
+
+      else if (memcmp(std, pRow, cbRow) != 0)
+      {
+         char msg[64];
+
+         /* No transform is expected on the threshold tests. */
+         sprintf(msg, "gamma: below threshold row %d changed", y);
+
+         png_error(pp, msg);
+      }
+   } /* row (y) loop */
+
+   dp->this.ps->validated = 1;
+}
+
+static void
+gamma_end(png_structp pp, png_infop pi)
+{
+   gamma_display *dp = voidcast(gamma_display*, png_get_progressive_ptr(pp));
+
+   if (!dp->this.speed)
+      gamma_image_validate(dp, pp, pi);
+   else
+      dp->this.ps->validated = 1;
+}
+
+/* A single test run checking a gamma transformation.
+ *
+ * maxabs: maximum absolute error as a fraction
+ * maxout: maximum output error in the output units
+ * maxpc:  maximum percentage error (as a percentage)
+ */
+static void
+gamma_test(png_modifier *pmIn, PNG_CONST png_byte colour_typeIn,
+    PNG_CONST png_byte bit_depthIn, PNG_CONST int palette_numberIn,
+    PNG_CONST int interlace_typeIn,
+    PNG_CONST double file_gammaIn, PNG_CONST double screen_gammaIn,
+    PNG_CONST png_byte sbitIn, PNG_CONST int threshold_testIn,
+    PNG_CONST char *name,
+    PNG_CONST int use_input_precisionIn, PNG_CONST int scale16In,
+    PNG_CONST int expand16In, PNG_CONST int do_backgroundIn,
+    PNG_CONST png_color_16 *bkgd_colorIn, double bkgd_gammaIn)
+{
+   gamma_display d;
+   context(&pmIn->this, fault);
+
+   gamma_display_init(&d, pmIn, FILEID(colour_typeIn, bit_depthIn,
+      palette_numberIn, interlace_typeIn, 0, 0, 0),
+      file_gammaIn, screen_gammaIn, sbitIn,
+      threshold_testIn, use_input_precisionIn, scale16In,
+      expand16In, do_backgroundIn, bkgd_colorIn, bkgd_gammaIn);
+
+   Try
+   {
+      png_structp pp;
+      png_infop pi;
+      gama_modification gama_mod;
+      srgb_modification srgb_mod;
+      sbit_modification sbit_mod;
+
+      /* For the moment don't use the png_modifier support here. */
+      d.pm->encoding_counter = 0;
+      modifier_set_encoding(d.pm); /* Just resets everything */
+      d.pm->current_gamma = d.file_gamma;
+
+      /* Make an appropriate modifier to set the PNG file gamma to the
+       * given gamma value and the sBIT chunk to the given precision.
+       */
+      d.pm->modifications = NULL;
+      gama_modification_init(&gama_mod, d.pm, d.file_gamma);
+      srgb_modification_init(&srgb_mod, d.pm, 127 /*delete*/);
+      if (d.sbit > 0)
+         sbit_modification_init(&sbit_mod, d.pm, d.sbit);
+
+      modification_reset(d.pm->modifications);
+
+      /* Get a png_struct for writing the image. */
+      pp = set_modifier_for_read(d.pm, &pi, d.this.id, name);
+      standard_palette_init(&d.this);
+
+      /* Introduce the correct read function. */
+      if (d.pm->this.progressive)
+      {
+         /* Share the row function with the standard implementation. */
+         png_set_progressive_read_fn(pp, &d, gamma_info, progressive_row,
+            gamma_end);
+
+         /* Now feed data into the reader until we reach the end: */
+         modifier_progressive_read(d.pm, pp, pi);
+      }
+      else
+      {
+         /* modifier_read expects a png_modifier* */
+         png_set_read_fn(pp, d.pm, modifier_read);
+
+         /* Check the header values: */
+         png_read_info(pp, pi);
+
+         /* Process the 'info' requirements. Only one image is generated */
+         gamma_info_imp(&d, pp, pi);
+
+         sequential_row(&d.this, pp, pi, -1, 0);
+
+         if (!d.this.speed)
+            gamma_image_validate(&d, pp, pi);
+         else
+            d.this.ps->validated = 1;
+      }
+
+      modifier_reset(d.pm);
+
+      if (d.pm->log && !d.threshold_test && !d.this.speed)
+         fprintf(stderr, "%d bit %s %s: max error %f (%.2g, %2g%%)\n",
+            d.this.bit_depth, colour_types[d.this.colour_type], name,
+            d.maxerrout, d.maxerrabs, 100*d.maxerrpc);
+
+      /* Log the summary values too. */
+      if (d.this.colour_type == 0 || d.this.colour_type == 4)
+      {
+         switch (d.this.bit_depth)
+         {
+         case 1:
+            break;
+
+         case 2:
+            if (d.maxerrout > d.pm->error_gray_2)
+               d.pm->error_gray_2 = d.maxerrout;
+
+            break;
+
+         case 4:
+            if (d.maxerrout > d.pm->error_gray_4)
+               d.pm->error_gray_4 = d.maxerrout;
+
+            break;
+
+         case 8:
+            if (d.maxerrout > d.pm->error_gray_8)
+               d.pm->error_gray_8 = d.maxerrout;
+
+            break;
+
+         case 16:
+            if (d.maxerrout > d.pm->error_gray_16)
+               d.pm->error_gray_16 = d.maxerrout;
+
+            break;
+
+         default:
+            png_error(pp, "bad bit depth (internal: 1)");
+         }
+      }
+
+      else if (d.this.colour_type == 2 || d.this.colour_type == 6)
+      {
+         switch (d.this.bit_depth)
+         {
+         case 8:
+
+            if (d.maxerrout > d.pm->error_color_8)
+               d.pm->error_color_8 = d.maxerrout;
+
+            break;
+
+         case 16:
+
+            if (d.maxerrout > d.pm->error_color_16)
+               d.pm->error_color_16 = d.maxerrout;
+
+            break;
+
+         default:
+            png_error(pp, "bad bit depth (internal: 2)");
+         }
+      }
+
+      else if (d.this.colour_type == 3)
+      {
+         if (d.maxerrout > d.pm->error_indexed)
+            d.pm->error_indexed = d.maxerrout;
+      }
+   }
+
+   Catch(fault)
+      modifier_reset((png_modifier*)fault);
+}
+
+static void gamma_threshold_test(png_modifier *pm, png_byte colour_type,
+    png_byte bit_depth, int interlace_type, double file_gamma,
+    double screen_gamma)
+{
+   size_t pos = 0;
+   char name[64];
+   pos = safecat(name, sizeof name, pos, "threshold ");
+   pos = safecatd(name, sizeof name, pos, file_gamma, 3);
+   pos = safecat(name, sizeof name, pos, "/");
+   pos = safecatd(name, sizeof name, pos, screen_gamma, 3);
+
+   (void)gamma_test(pm, colour_type, bit_depth, 0/*palette*/, interlace_type,
+      file_gamma, screen_gamma, 0/*sBIT*/, 1/*threshold test*/, name,
+      0 /*no input precision*/,
+      0 /*no scale16*/, 0 /*no expand16*/, 0 /*no background*/, 0 /*hence*/,
+      0 /*no background gamma*/);
+}
+
+static void
+perform_gamma_threshold_tests(png_modifier *pm)
+{
+   png_byte colour_type = 0;
+   png_byte bit_depth = 0;
+   int palette_number = 0;
+
+   /* Don't test more than one instance of each palette - it's pointless, in
+    * fact this test is somewhat excessive since libpng doesn't make this
+    * decision based on colour type or bit depth!
+    */
+   while (next_format(&colour_type, &bit_depth, &palette_number))
+      if (palette_number == 0)
+   {
+      double test_gamma = 1.0;
+      while (test_gamma >= .4)
+      {
+         /* There's little point testing the interlacing vs non-interlacing,
+          * but this can be set from the command line.
+          */
+         gamma_threshold_test(pm, colour_type, bit_depth, pm->interlace_type,
+            test_gamma, 1/test_gamma);
+         test_gamma *= .95;
+      }
+
+      /* And a special test for sRGB */
+      gamma_threshold_test(pm, colour_type, bit_depth, pm->interlace_type,
+          .45455, 2.2);
+
+      if (fail(pm))
+         return;
+   }
+}
+
+static void gamma_transform_test(png_modifier *pm,
+   PNG_CONST png_byte colour_type, PNG_CONST png_byte bit_depth,
+   PNG_CONST int palette_number,
+   PNG_CONST int interlace_type, PNG_CONST double file_gamma,
+   PNG_CONST double screen_gamma, PNG_CONST png_byte sbit,
+   PNG_CONST int use_input_precision, PNG_CONST int scale16)
+{
+   size_t pos = 0;
+   char name[64];
+
+   if (sbit != bit_depth && sbit != 0)
+   {
+      pos = safecat(name, sizeof name, pos, "sbit(");
+      pos = safecatn(name, sizeof name, pos, sbit);
+      pos = safecat(name, sizeof name, pos, ") ");
+   }
+
+   else
+      pos = safecat(name, sizeof name, pos, "gamma ");
+
+   if (scale16)
+      pos = safecat(name, sizeof name, pos, "16to8 ");
+
+   pos = safecatd(name, sizeof name, pos, file_gamma, 3);
+   pos = safecat(name, sizeof name, pos, "->");
+   pos = safecatd(name, sizeof name, pos, screen_gamma, 3);
+
+   gamma_test(pm, colour_type, bit_depth, palette_number, interlace_type,
+      file_gamma, screen_gamma, sbit, 0, name, use_input_precision,
+      scale16, pm->test_gamma_expand16, 0 , 0, 0);
+}
+
+static void perform_gamma_transform_tests(png_modifier *pm)
+{
+   png_byte colour_type = 0;
+   png_byte bit_depth = 0;
+   int palette_number = 0;
+
+   while (next_format(&colour_type, &bit_depth, &palette_number))
+   {
+      unsigned int i, j;
+
+      for (i=0; i<pm->ngamma_tests; ++i) for (j=0; j<pm->ngamma_tests; ++j)
+         if (i != j)
+         {
+            gamma_transform_test(pm, colour_type, bit_depth, palette_number,
+               pm->interlace_type, 1/pm->gammas[i], pm->gammas[j], 0/*sBIT*/,
+               pm->use_input_precision, 0 /*do not scale16*/);
+
+            if (fail(pm))
+               return;
+         }
+   }
+}
+
+static void perform_gamma_sbit_tests(png_modifier *pm)
+{
+   png_byte sbit;
+
+   /* The only interesting cases are colour and grayscale, alpha is ignored here
+    * for overall speed.  Only bit depths where sbit is less than the bit depth
+    * are tested.
+    */
+   for (sbit=pm->sbitlow; sbit<(1<<READ_BDHI); ++sbit)
+   {
+      png_byte colour_type, bit_depth;
+      int npalette;
+
+      colour_type = bit_depth = 0;
+      npalette = 0;
+
+      while (next_format(&colour_type, &bit_depth, &npalette))
+         if ((colour_type & PNG_COLOR_MASK_ALPHA) == 0 &&
+            ((colour_type == 3 && sbit < 8) ||
+            (colour_type != 3 && sbit < bit_depth)))
+      {
+         unsigned int i;
+
+         for (i=0; i<pm->ngamma_tests; ++i)
+         {
+            unsigned int j;
+
+            for (j=0; j<pm->ngamma_tests; ++j) if (i != j)
+            {
+               gamma_transform_test(pm, colour_type, bit_depth, npalette,
+                  pm->interlace_type, 1/pm->gammas[i], pm->gammas[j],
+                  sbit, pm->use_input_precision_sbit, 0 /*scale16*/);
+
+               if (fail(pm))
+                  return;
+            }
+         }
+      }
+   }
+}
+
+/* Note that this requires a 16 bit source image but produces 8 bit output, so
+ * we only need the 16bit write support, but the 16 bit images are only
+ * generated if DO_16BIT is defined.
+ */
+#ifdef DO_16BIT
+static void perform_gamma_scale16_tests(png_modifier *pm)
+{
+#  ifndef PNG_MAX_GAMMA_8
+#     define PNG_MAX_GAMMA_8 11
+#  endif
+   /* Include the alpha cases here. Note that sbit matches the internal value
+    * used by the library - otherwise we will get spurious errors from the
+    * internal sbit style approximation.
+    *
+    * The threshold test is here because otherwise the 16 to 8 conversion will
+    * proceed *without* gamma correction, and the tests above will fail (but not
+    * by much) - this could be fixed, it only appears with the -g option.
+    */
+   unsigned int i, j;
+   for (i=0; i<pm->ngamma_tests; ++i)
+   {
+      for (j=0; j<pm->ngamma_tests; ++j)
+      {
+         if (i != j &&
+             fabs(pm->gammas[j]/pm->gammas[i]-1) >= PNG_GAMMA_THRESHOLD)
+         {
+            gamma_transform_test(pm, 0, 16, 0, pm->interlace_type,
+               1/pm->gammas[i], pm->gammas[j], PNG_MAX_GAMMA_8,
+               pm->use_input_precision_16to8, 1 /*scale16*/);
+
+            if (fail(pm))
+               return;
+
+            gamma_transform_test(pm, 2, 16, 0, pm->interlace_type,
+               1/pm->gammas[i], pm->gammas[j], PNG_MAX_GAMMA_8,
+               pm->use_input_precision_16to8, 1 /*scale16*/);
+
+            if (fail(pm))
+               return;
+
+            gamma_transform_test(pm, 4, 16, 0, pm->interlace_type,
+               1/pm->gammas[i], pm->gammas[j], PNG_MAX_GAMMA_8,
+               pm->use_input_precision_16to8, 1 /*scale16*/);
+
+            if (fail(pm))
+               return;
+
+            gamma_transform_test(pm, 6, 16, 0, pm->interlace_type,
+               1/pm->gammas[i], pm->gammas[j], PNG_MAX_GAMMA_8,
+               pm->use_input_precision_16to8, 1 /*scale16*/);
+
+            if (fail(pm))
+               return;
+         }
+      }
+   }
+}
+#endif /* 16 to 8 bit conversion */
+
+#if defined PNG_READ_BACKGROUND_SUPPORTED ||\
+   defined PNG_READ_ALPHA_MODE_SUPPORTED
+static void gamma_composition_test(png_modifier *pm,
+   PNG_CONST png_byte colour_type, PNG_CONST png_byte bit_depth,
+   PNG_CONST int palette_number,
+   PNG_CONST int interlace_type, PNG_CONST double file_gamma,
+   PNG_CONST double screen_gamma,
+   PNG_CONST int use_input_precision, PNG_CONST int do_background,
+   PNG_CONST int expand_16)
+{
+   size_t pos = 0;
+   png_const_charp base;
+   double bg;
+   char name[128];
+   png_color_16 background;
+
+   /* Make up a name and get an appropriate background gamma value. */
+   switch (do_background)
+   {
+      default:
+         base = "";
+         bg = 4; /* should not be used */
+         break;
+      case PNG_BACKGROUND_GAMMA_SCREEN:
+         base = " bckg(Screen):";
+         bg = 1/screen_gamma;
+         break;
+      case PNG_BACKGROUND_GAMMA_FILE:
+         base = " bckg(File):";
+         bg = file_gamma;
+         break;
+      case PNG_BACKGROUND_GAMMA_UNIQUE:
+         base = " bckg(Unique):";
+         /* This tests the handling of a unique value, the math is such that the
+          * value tends to be <1, but is neither screen nor file (even if they
+          * match!)
+          */
+         bg = (file_gamma + screen_gamma) / 3;
+         break;
+#ifdef PNG_READ_ALPHA_MODE_SUPPORTED
+      case ALPHA_MODE_OFFSET + PNG_ALPHA_PNG:
+         base = " alpha(PNG)";
+         bg = 4; /* should not be used */
+         break;
+      case ALPHA_MODE_OFFSET + PNG_ALPHA_STANDARD:
+         base = " alpha(Porter-Duff)";
+         bg = 4; /* should not be used */
+         break;
+      case ALPHA_MODE_OFFSET + PNG_ALPHA_OPTIMIZED:
+         base = " alpha(Optimized)";
+         bg = 4; /* should not be used */
+         break;
+      case ALPHA_MODE_OFFSET + PNG_ALPHA_BROKEN:
+         base = " alpha(Broken)";
+         bg = 4; /* should not be used */
+         break;
+#endif
+   }
+
+   /* Use random background values - the background is always presented in the
+    * output space (8 or 16 bit components).
+    */
+   if (expand_16 || bit_depth == 16)
+   {
+      png_uint_32 r = random_32();
+
+      background.red = (png_uint_16)r;
+      background.green = (png_uint_16)(r >> 16);
+      r = random_32();
+      background.blue = (png_uint_16)r;
+      background.gray = (png_uint_16)(r >> 16);
+   }
+
+   else /* 8 bit colors */
+   {
+      png_uint_32 r = random_32();
+
+      background.red = (png_byte)r;
+      background.green = (png_byte)(r >> 8);
+      background.blue = (png_byte)(r >> 16);
+      background.gray = (png_byte)(r >> 24);
+   }
+
+   background.index = 193; /* rgb(193,193,193) to detect errors */
+   if (!(colour_type & PNG_COLOR_MASK_COLOR))
+   {
+      /* Grayscale input, we do not convert to RGB (TBD), so we must set the
+       * background to gray - else libpng seems to fail.
+       */
+      background.red = background.green = background.blue = background.gray;
+   }
+
+   pos = safecat(name, sizeof name, pos, "gamma ");
+   pos = safecatd(name, sizeof name, pos, file_gamma, 3);
+   pos = safecat(name, sizeof name, pos, "->");
+   pos = safecatd(name, sizeof name, pos, screen_gamma, 3);
+
+   pos = safecat(name, sizeof name, pos, base);
+   if (do_background < ALPHA_MODE_OFFSET)
+   {
+      /* Include the background color and gamma in the name: */
+      pos = safecat(name, sizeof name, pos, "(");
+      /* This assumes no expand gray->rgb - the current code won't handle that!
+       */
+      if (colour_type & PNG_COLOR_MASK_COLOR)
+      {
+         pos = safecatn(name, sizeof name, pos, background.red);
+         pos = safecat(name, sizeof name, pos, ",");
+         pos = safecatn(name, sizeof name, pos, background.green);
+         pos = safecat(name, sizeof name, pos, ",");
+         pos = safecatn(name, sizeof name, pos, background.blue);
+      }
+      else
+         pos = safecatn(name, sizeof name, pos, background.gray);
+      pos = safecat(name, sizeof name, pos, ")^");
+      pos = safecatd(name, sizeof name, pos, bg, 3);
+   }
+
+   gamma_test(pm, colour_type, bit_depth, palette_number, interlace_type,
+      file_gamma, screen_gamma, 0/*sBIT*/, 0, name, use_input_precision,
+      0/*strip 16*/, expand_16, do_background, &background, bg);
+}
+
+
+static void
+perform_gamma_composition_tests(png_modifier *pm, int do_background,
+   int expand_16)
+{
+   png_byte colour_type = 0;
+   png_byte bit_depth = 0;
+   int palette_number = 0;
+
+   /* Skip the non-alpha cases - there is no setting of a transparency colour at
+    * present.
+    */
+   while (next_format(&colour_type, &bit_depth, &palette_number))
+      if ((colour_type & PNG_COLOR_MASK_ALPHA) != 0)
+   {
+      unsigned int i, j;
+
+      /* Don't skip the i==j case here - it's relevant. */
+      for (i=0; i<pm->ngamma_tests; ++i) for (j=0; j<pm->ngamma_tests; ++j)
+      {
+         gamma_composition_test(pm, colour_type, bit_depth, palette_number,
+            pm->interlace_type, 1/pm->gammas[i], pm->gammas[j],
+            pm->use_input_precision, do_background, expand_16);
+
+         if (fail(pm))
+            return;
+      }
+   }
+}
+#endif /* READ_BACKGROUND || READ_ALPHA_MODE */
+
+static void
+init_gamma_errors(png_modifier *pm)
+{
+   pm->error_gray_2 = pm->error_gray_4 = pm->error_gray_8 = 0;
+   pm->error_color_8 = 0;
+   pm->error_indexed = 0;
+   pm->error_gray_16 = pm->error_color_16 = 0;
+}
+
+static void
+summarize_gamma_errors(png_modifier *pm, png_const_charp who, int low_bit_depth)
+{
+   if (who)
+      printf("Gamma correction with %s:\n", who);
+
+   if (low_bit_depth)
+   {
+      printf("  2 bit gray:  %.5f\n", pm->error_gray_2);
+      printf("  4 bit gray:  %.5f\n", pm->error_gray_4);
+      printf("  8 bit gray:  %.5f\n", pm->error_gray_8);
+      printf("  8 bit color: %.5f\n", pm->error_color_8);
+      printf("  indexed:     %.5f\n", pm->error_indexed);
+   }
+
+#ifdef DO_16BIT
+   printf(" 16 bit gray:  %.5f\n", pm->error_gray_16);
+   printf(" 16 bit color: %.5f\n", pm->error_color_16);
+#endif
+}
+
+static void
+perform_gamma_test(png_modifier *pm, int summary)
+{
+   /*TODO: remove this*/
+   /* Save certain values for the temporary overrides below. */
+   unsigned int calculations_use_input_precision =
+      pm->calculations_use_input_precision;
+   double maxout8 = pm->maxout8;
+
+   /* First some arbitrary no-transform tests: */
+   if (!pm->this.speed && pm->test_gamma_threshold)
+   {
+      perform_gamma_threshold_tests(pm);
+
+      if (fail(pm))
+         return;
+   }
+
+   /* Now some real transforms. */
+   if (pm->test_gamma_transform)
+   {
+      init_gamma_errors(pm);
+      /*TODO: remove this.  Necessary because the current libpng
+       * implementation works in 8 bits:
+       */
+      if (pm->test_gamma_expand16)
+         pm->calculations_use_input_precision = 1;
+      perform_gamma_transform_tests(pm);
+      if (!calculations_use_input_precision)
+         pm->calculations_use_input_precision = 0;
+
+      if (summary)
+      {
+         printf("Gamma correction error summary\n\n");
+         printf("The printed value is the maximum error in the pixel values\n");
+         printf("calculated by the libpng gamma correction code.  The error\n");
+         printf("is calculated as the difference between the output pixel\n");
+         printf("value (always an integer) and the ideal value from the\n");
+         printf("libpng specification (typically not an integer).\n\n");
+
+         printf("Expect this value to be less than .5 for 8 bit formats,\n");
+         printf("less than 1 for formats with fewer than 8 bits and a small\n");
+         printf("number (typically less than 5) for the 16 bit formats.\n");
+         printf("For performance reasons the value for 16 bit formats\n");
+         printf("increases when the image file includes an sBIT chunk.\n\n");
+
+         summarize_gamma_errors(pm, 0/*who*/, 1);
+      }
+   }
+
+   /* The sbit tests produce much larger errors: */
+   if (pm->test_gamma_sbit)
+   {
+      init_gamma_errors(pm);
+      perform_gamma_sbit_tests(pm);
+
+      if (summary)
+         summarize_gamma_errors(pm, "sBIT", pm->sbitlow < 8U);
+   }
+
+#ifdef DO_16BIT /* Should be READ_16BIT_SUPPORTED */
+   if (pm->test_gamma_scale16)
+   {
+      /* The 16 to 8 bit strip operations: */
+      init_gamma_errors(pm);
+      perform_gamma_scale16_tests(pm);
+
+      if (summary)
+      {
+         printf("Gamma correction with 16 to 8 bit reduction:\n");
+         printf(" 16 bit gray:  %.5f\n", pm->error_gray_16);
+         printf(" 16 bit color: %.5f\n", pm->error_color_16);
+      }
+   }
+#endif
+
+#ifdef PNG_READ_BACKGROUND_SUPPORTED
+   if (pm->test_gamma_background)
+   {
+      init_gamma_errors(pm);
+
+      /*TODO: remove this.  Necessary because the current libpng
+       * implementation works in 8 bits:
+       */
+      if (pm->test_gamma_expand16)
+      {
+         pm->calculations_use_input_precision = 1;
+         pm->maxout8 = .499; /* because the 16 bit background is smashed */
+      }
+      perform_gamma_composition_tests(pm, PNG_BACKGROUND_GAMMA_UNIQUE,
+         pm->test_gamma_expand16);
+      if (!calculations_use_input_precision)
+         pm->calculations_use_input_precision = 0;
+      pm->maxout8 = maxout8;
+
+      if (summary)
+         summarize_gamma_errors(pm, "background", 1);
+   }
+#endif
+
+#ifdef PNG_READ_ALPHA_MODE_SUPPORTED
+   if (pm->test_gamma_alpha_mode)
+   {
+      int do_background;
+
+      init_gamma_errors(pm);
+
+      /*TODO: remove this.  Necessary because the current libpng
+       * implementation works in 8 bits:
+       */
+      if (pm->test_gamma_expand16)
+         pm->calculations_use_input_precision = 1;
+      for (do_background = ALPHA_MODE_OFFSET + PNG_ALPHA_STANDARD;
+         do_background <= ALPHA_MODE_OFFSET + PNG_ALPHA_BROKEN && !fail(pm);
+         ++do_background)
+         perform_gamma_composition_tests(pm, do_background,
+            pm->test_gamma_expand16);
+      if (!calculations_use_input_precision)
+         pm->calculations_use_input_precision = 0;
+
+      if (summary)
+         summarize_gamma_errors(pm, "alpha mode", 1);
+   }
+#endif
+}
+#endif /* PNG_READ_GAMMA_SUPPORTED */
+
+/* INTERLACE MACRO VALIDATION */
+/* This is copied verbatim from the specification, it is simply the pass
+ * number in which each pixel in each 8x8 tile appears.  The array must
+ * be indexed adam7[y][x] and notice that the pass numbers are based at
+ * 1, not 0 - the base libpng uses.
+ */
+static PNG_CONST
+png_byte adam7[8][8] =
+{
+   { 1,6,4,6,2,6,4,6 },
+   { 7,7,7,7,7,7,7,7 },
+   { 5,6,5,6,5,6,5,6 },
+   { 7,7,7,7,7,7,7,7 },
+   { 3,6,4,6,3,6,4,6 },
+   { 7,7,7,7,7,7,7,7 },
+   { 5,6,5,6,5,6,5,6 },
+   { 7,7,7,7,7,7,7,7 }
+};
+
+/* This routine validates all the interlace support macros in png.h for
+ * a variety of valid PNG widths and heights.  It uses a number of similarly
+ * named internal routines that feed off the above array.
+ */
+static png_uint_32
+png_pass_start_row(int pass)
+{
+   int x, y;
+   ++pass;
+   for (y=0; y<8; ++y) for (x=0; x<8; ++x) if (adam7[y][x] == pass)
+      return y;
+   return 0xf;
+}
+
+static png_uint_32
+png_pass_start_col(int pass)
+{
+   int x, y;
+   ++pass;
+   for (x=0; x<8; ++x) for (y=0; y<8; ++y) if (adam7[y][x] == pass)
+      return x;
+   return 0xf;
+}
+
+static int
+png_pass_row_shift(int pass)
+{
+   int x, y, base=(-1), inc=8;
+   ++pass;
+   for (y=0; y<8; ++y) for (x=0; x<8; ++x) if (adam7[y][x] == pass)
+   {
+      if (base == (-1))
+         base = y;
+      else if (base == y)
+         {}
+      else if (inc == y-base)
+         base=y;
+      else if (inc == 8)
+         inc = y-base, base=y;
+      else if (inc != y-base)
+         return 0xff; /* error - more than one 'inc' value! */
+   }
+
+   if (base == (-1)) return 0xfe; /* error - no row in pass! */
+
+   /* The shift is always 1, 2 or 3 - no pass has all the rows! */
+   switch (inc)
+   {
+case 2: return 1;
+case 4: return 2;
+case 8: return 3;
+default: break;
+   }
+
+   /* error - unrecognized 'inc' */
+   return (inc << 8) + 0xfd;
+}
+
+static int
+png_pass_col_shift(int pass)
+{
+   int x, y, base=(-1), inc=8;
+   ++pass;
+   for (x=0; x<8; ++x) for (y=0; y<8; ++y) if (adam7[y][x] == pass)
+   {
+      if (base == (-1))
+         base = x;
+      else if (base == x)
+         {}
+      else if (inc == x-base)
+         base=x;
+      else if (inc == 8)
+         inc = x-base, base=x;
+      else if (inc != x-base)
+         return 0xff; /* error - more than one 'inc' value! */
+   }
+
+   if (base == (-1)) return 0xfe; /* error - no row in pass! */
+
+   /* The shift is always 1, 2 or 3 - no pass has all the rows! */
+   switch (inc)
+   {
+case 1: return 0; /* pass 7 has all the columns */
+case 2: return 1;
+case 4: return 2;
+case 8: return 3;
+default: break;
+   }
+
+   /* error - unrecognized 'inc' */
+   return (inc << 8) + 0xfd;
+}
+
+static png_uint_32
+png_row_from_pass_row(png_uint_32 yIn, int pass)
+{
+   /* By examination of the array: */
+   switch (pass)
+   {
+case 0: return yIn * 8;
+case 1: return yIn * 8;
+case 2: return yIn * 8 + 4;
+case 3: return yIn * 4;
+case 4: return yIn * 4 + 2;
+case 5: return yIn * 2;
+case 6: return yIn * 2 + 1;
+default: break;
+   }
+
+   return 0xff; /* bad pass number */
+}
+
+static png_uint_32
+png_col_from_pass_col(png_uint_32 xIn, int pass)
+{
+   /* By examination of the array: */
+   switch (pass)
+   {
+case 0: return xIn * 8;
+case 1: return xIn * 8 + 4;
+case 2: return xIn * 4;
+case 3: return xIn * 4 + 2;
+case 4: return xIn * 2;
+case 5: return xIn * 2 + 1;
+case 6: return xIn;
+default: break;
+   }
+
+   return 0xff; /* bad pass number */
+}
+
+static int
+png_row_in_interlace_pass(png_uint_32 y, int pass)
+{
+   /* Is row 'y' in pass 'pass'? */
+   int x;
+   y &= 7;
+   ++pass;
+   for (x=0; x<8; ++x) if (adam7[y][x] == pass)
+      return 1;
+
+   return 0;
+}
+
+static int
+png_col_in_interlace_pass(png_uint_32 x, int pass)
+{
+   /* Is column 'x' in pass 'pass'? */
+   int y;
+   x &= 7;
+   ++pass;
+   for (y=0; y<8; ++y) if (adam7[y][x] == pass)
+      return 1;
+
+   return 0;
+}
+
+static png_uint_32
+png_pass_rows(png_uint_32 height, int pass)
+{
+   png_uint_32 tiles = height>>3;
+   png_uint_32 rows = 0;
+   unsigned int x, y;
+
+   height &= 7;
+   ++pass;
+   for (y=0; y<8; ++y) for (x=0; x<8; ++x) if (adam7[y][x] == pass)
+   {
+      rows += tiles;
+      if (y < height) ++rows;
+      break; /* i.e. break the 'x', column, loop. */
+   }
+
+   return rows;
+}
+
+static png_uint_32
+png_pass_cols(png_uint_32 width, int pass)
+{
+   png_uint_32 tiles = width>>3;
+   png_uint_32 cols = 0;
+   unsigned int x, y;
+
+   width &= 7;
+   ++pass;
+   for (x=0; x<8; ++x) for (y=0; y<8; ++y) if (adam7[y][x] == pass)
+   {
+      cols += tiles;
+      if (x < width) ++cols;
+      break; /* i.e. break the 'y', row, loop. */
+   }
+
+   return cols;
+}
+
+static void
+perform_interlace_macro_validation(void)
+{
+   /* The macros to validate, first those that depend only on pass:
+    *
+    * PNG_PASS_START_ROW(pass)
+    * PNG_PASS_START_COL(pass)
+    * PNG_PASS_ROW_SHIFT(pass)
+    * PNG_PASS_COL_SHIFT(pass)
+    */
+   int pass;
+
+   for (pass=0; pass<7; ++pass)
+   {
+      png_uint_32 m, f, v;
+
+      m = PNG_PASS_START_ROW(pass);
+      f = png_pass_start_row(pass);
+      if (m != f)
+      {
+         fprintf(stderr, "PNG_PASS_START_ROW(%d) = %u != %x\n", pass, m, f);
+         exit(1);
+      }
+
+      m = PNG_PASS_START_COL(pass);
+      f = png_pass_start_col(pass);
+      if (m != f)
+      {
+         fprintf(stderr, "PNG_PASS_START_COL(%d) = %u != %x\n", pass, m, f);
+         exit(1);
+      }
+
+      m = PNG_PASS_ROW_SHIFT(pass);
+      f = png_pass_row_shift(pass);
+      if (m != f)
+      {
+         fprintf(stderr, "PNG_PASS_ROW_SHIFT(%d) = %u != %x\n", pass, m, f);
+         exit(1);
+      }
+
+      m = PNG_PASS_COL_SHIFT(pass);
+      f = png_pass_col_shift(pass);
+      if (m != f)
+      {
+         fprintf(stderr, "PNG_PASS_COL_SHIFT(%d) = %u != %x\n", pass, m, f);
+         exit(1);
+      }
+
+      /* Macros that depend on the image or sub-image height too:
+       *
+       * PNG_PASS_ROWS(height, pass)
+       * PNG_PASS_COLS(width, pass)
+       * PNG_ROW_FROM_PASS_ROW(yIn, pass)
+       * PNG_COL_FROM_PASS_COL(xIn, pass)
+       * PNG_ROW_IN_INTERLACE_PASS(y, pass)
+       * PNG_COL_IN_INTERLACE_PASS(x, pass)
+       */
+      for (v=0;;)
+      {
+         /* First the base 0 stuff: */
+         m = PNG_ROW_FROM_PASS_ROW(v, pass);
+         f = png_row_from_pass_row(v, pass);
+         if (m != f)
+         {
+            fprintf(stderr, "PNG_ROW_FROM_PASS_ROW(%u, %d) = %u != %x\n",
+               v, pass, m, f);
+            exit(1);
+         }
+
+         m = PNG_COL_FROM_PASS_COL(v, pass);
+         f = png_col_from_pass_col(v, pass);
+         if (m != f)
+         {
+            fprintf(stderr, "PNG_COL_FROM_PASS_COL(%u, %d) = %u != %x\n",
+               v, pass, m, f);
+            exit(1);
+         }
+
+         m = PNG_ROW_IN_INTERLACE_PASS(v, pass);
+         f = png_row_in_interlace_pass(v, pass);
+         if (m != f)
+         {
+            fprintf(stderr, "PNG_ROW_IN_INTERLACE_PASS(%u, %d) = %u != %x\n",
+               v, pass, m, f);
+            exit(1);
+         }
+
+         m = PNG_COL_IN_INTERLACE_PASS(v, pass);
+         f = png_col_in_interlace_pass(v, pass);
+         if (m != f)
+         {
+            fprintf(stderr, "PNG_COL_IN_INTERLACE_PASS(%u, %d) = %u != %x\n",
+               v, pass, m, f);
+            exit(1);
+         }
+
+         /* Then the base 1 stuff: */
+         ++v;
+         m = PNG_PASS_ROWS(v, pass);
+         f = png_pass_rows(v, pass);
+         if (m != f)
+         {
+            fprintf(stderr, "PNG_PASS_ROWS(%u, %d) = %u != %x\n",
+               v, pass, m, f);
+            exit(1);
+         }
+
+         m = PNG_PASS_COLS(v, pass);
+         f = png_pass_cols(v, pass);
+         if (m != f)
+         {
+            fprintf(stderr, "PNG_PASS_COLS(%u, %d) = %u != %x\n",
+               v, pass, m, f);
+            exit(1);
+         }
+
+         /* Move to the next v - the stepping algorithm starts skipping
+          * values above 1024.
+          */
+         if (v > 1024)
+         {
+            if (v == PNG_UINT_31_MAX)
+               break;
+
+            v = (v << 1) ^ v;
+            if (v >= PNG_UINT_31_MAX)
+               v = PNG_UINT_31_MAX-1;
+         }
+      }
+   }
+}
+
+/* Test color encodings. These values are back-calculated from the published
+ * chromaticities.  The values are accurate to about 14 decimal places; 15 are
+ * given.  These values are much more accurate than the ones given in the spec,
+ * which typically don't exceed 4 decimal places.  This allows testing of the
+ * libpng code to its theoretical accuracy of 4 decimal places.  (If pngvalid
+ * used the published errors the 'slack' permitted would have to be +/-.5E-4 or
+ * more.)
+ *
+ * The png_modifier code assumes that encodings[0] is sRGB and treats it
+ * specially: do not change the first entry in this list!
+ */
+static PNG_CONST color_encoding test_encodings[] =
+{
+/* sRGB: must be first in this list! */
+/*gamma:*/ { 1/2.2,
+/*red:  */ { 0.412390799265959, 0.212639005871510, 0.019330818715592 },
+/*green:*/ { 0.357584339383878, 0.715168678767756, 0.119194779794626 },
+/*blue: */ { 0.180480788401834, 0.072192315360734, 0.950532152249660} },
+/* Kodak ProPhoto (wide gamut) */
+/*gamma:*/ { 1/1.6 /*approximate: uses 1.8 power law compared to sRGB 2.4*/,
+/*red:  */ { 0.797760489672303, 0.288071128229293, 0.000000000000000 },
+/*green:*/ { 0.135185837175740, 0.711843217810102, 0.000000000000000 },
+/*blue: */ { 0.031349349581525, 0.000085653960605, 0.825104602510460} },
+/* Adobe RGB (1998) */
+/*gamma:*/ { 1/(2+51./256),
+/*red:  */ { 0.576669042910131, 0.297344975250536, 0.027031361386412 },
+/*green:*/ { 0.185558237906546, 0.627363566255466, 0.070688852535827 },
+/*blue: */ { 0.188228646234995, 0.075291458493998, 0.991337536837639} },
+/* Adobe Wide Gamut RGB */
+/*gamma:*/ { 1/(2+51./256),
+/*red:  */ { 0.716500716779386, 0.258728243040113, 0.000000000000000 },
+/*green:*/ { 0.101020574397477, 0.724682314948566, 0.051211818965388 },
+/*blue: */ { 0.146774385252705, 0.016589442011321, 0.773892783545073} },
+};
+
+/* signal handler
+ *
+ * This attempts to trap signals and escape without crashing.  It needs a
+ * context pointer so that it can throw an exception (call longjmp) to recover
+ * from the condition; this is handled by making the png_modifier used by 'main'
+ * into a global variable.
+ */
+static png_modifier pm;
+
+static void signal_handler(int signum)
+{
+
+   size_t pos = 0;
+   char msg[64];
+
+   pos = safecat(msg, sizeof msg, pos, "caught signal: ");
+
+   switch (signum)
+   {
+      case SIGABRT:
+         pos = safecat(msg, sizeof msg, pos, "abort");
+         break;
+
+      case SIGFPE:
+         pos = safecat(msg, sizeof msg, pos, "floating point exception");
+         break;
+
+      case SIGILL:
+         pos = safecat(msg, sizeof msg, pos, "illegal instruction");
+         break;
+
+      case SIGINT:
+         pos = safecat(msg, sizeof msg, pos, "interrupt");
+         break;
+
+      case SIGSEGV:
+         pos = safecat(msg, sizeof msg, pos, "invalid memory access");
+         break;
+
+      case SIGTERM:
+         pos = safecat(msg, sizeof msg, pos, "termination request");
+         break;
+
+      default:
+         pos = safecat(msg, sizeof msg, pos, "unknown ");
+         pos = safecatn(msg, sizeof msg, pos, signum);
+         break;
+   }
+
+   store_log(&pm.this, NULL/*png_structp*/, msg, 1/*error*/);
+
+   /* And finally throw an exception so we can keep going, unless this is
+    * SIGTERM in which case stop now.
+    */
+   if (signum != SIGTERM)
+   {
+      struct exception_context *the_exception_context =
+         &pm.this.exception_context;
+
+      Throw &pm.this;
+   }
+
+   else
+      exit(1);
+}
+
+/* main program */
+int main(int argc, PNG_CONST char **argv)
+{
+   volatile int summary = 1;  /* Print the error summary at the end */
+   volatile int memstats = 0; /* Print memory statistics at the end */
+
+   /* Create the given output file on success: */
+   PNG_CONST char *volatile touch = NULL;
+
+   /* This is an array of standard gamma values (believe it or not I've seen
+    * every one of these mentioned somewhere.)
+    *
+    * In the following list the most useful values are first!
+    */
+   static double
+      gammas[]={2.2, 1.0, 2.2/1.45, 1.8, 1.5, 2.4, 2.5, 2.62, 2.9};
+
+   /* This records the command and arguments: */
+   size_t cp = 0;
+   char command[1024];
+
+   anon_context(&pm.this);
+
+   /* Add appropriate signal handlers, just the ANSI specified ones: */
+   signal(SIGABRT, signal_handler);
+   signal(SIGFPE, signal_handler);
+   signal(SIGILL, signal_handler);
+   signal(SIGINT, signal_handler);
+   signal(SIGSEGV, signal_handler);
+   signal(SIGTERM, signal_handler);
+
+#ifdef HAVE_FEENABLEEXCEPT
+   /* Only required to enable FP exceptions on platforms where they start off
+    * disabled; this is not necessary but if it is not done pngvalid will likely
+    * end up ignoring FP conditions that other platforms fault.
+    */
+   feenableexcept(FE_DIVBYZERO | FE_INVALID | FE_OVERFLOW);
+#endif
+
+   modifier_init(&pm);
+
+   /* Preallocate the image buffer, because we know how big it needs to be,
+    * note that, for testing purposes, it is deliberately mis-aligned by tag
+    * bytes either side.  All rows have an additional five bytes of padding for
+    * overwrite checking.
+    */
+   store_ensure_image(&pm.this, NULL, 2, TRANSFORM_ROWMAX, TRANSFORM_HEIGHTMAX);
+
+   /* Don't give argv[0], it's normally some horrible libtool string: */
+   cp = safecat(command, sizeof command, cp, "pngvalid");
+
+   /* Default to error on warning: */
+   pm.this.treat_warnings_as_errors = 1;
+
+   /* Store the test gammas */
+   pm.gammas = gammas;
+   pm.ngammas = (sizeof gammas) / (sizeof gammas[0]);
+   pm.ngamma_tests = 0; /* default to off */
+
+   /* And the test encodings */
+   pm.encodings = test_encodings;
+   pm.nencodings = (sizeof test_encodings) / (sizeof test_encodings[0]);
+
+   pm.sbitlow = 8U; /* because libpng doesn't do sBIT below 8! */
+   /* The following allows results to pass if they correspond to anything in the
+    * transformed range [input-.5,input+.5]; this is is required because of the
+    * way libpng treates the 16_TO_8 flag when building the gamma tables.
+    *
+    * TODO: review this
+    */
+   pm.use_input_precision_16to8 = 1U;
+
+   /* Some default values (set the behavior for 'make check' here).
+    * These values simply control the maximum error permitted in the gamma
+    * transformations.  The practial limits for human perception are described
+    * below (the setting for maxpc16), however for 8 bit encodings it isn't
+    * possible to meet the accepted capabilities of human vision - i.e. 8 bit
+    * images can never be good enough, regardless of encoding.
+    */
+   pm.maxout8 = .1;     /* Arithmetic error in *encoded* value */
+   pm.maxabs8 = .00005; /* 1/20000 */
+   pm.maxcalc8 = .004;  /* +/-1 in 8 bits for compose errors */
+   pm.maxpc8 = .499;    /* I.e., .499% fractional error */
+   pm.maxout16 = .499;  /* Error in *encoded* value */
+   pm.maxabs16 = .00005;/* 1/20000 */
+   pm.maxcalc16 =.000015;/* +/-1 in 16 bits for compose errors */
+
+   /* NOTE: this is a reasonable perceptual limit. We assume that humans can
+    * perceive light level differences of 1% over a 100:1 range, so we need to
+    * maintain 1 in 10000 accuracy (in linear light space), which is what the
+    * following guarantees.  It also allows significantly higher errors at
+    * higher 16 bit values, which is important for performance.  The actual
+    * maximum 16 bit error is about +/-1.9 in the fixed point implementation but
+    * this is only allowed for values >38149 by the following:
+    */
+   pm.maxpc16 = .005;   /* I.e., 1/200% - 1/20000 */
+
+   /* Now parse the command line options. */
+   while (--argc >= 1)
+   {
+      int catmore = 0; /* Set if the argument has an argument. */
+
+      /* Record each argument for posterity: */
+      cp = safecat(command, sizeof command, cp, " ");
+      cp = safecat(command, sizeof command, cp, *++argv);
+
+      if (strcmp(*argv, "-v") == 0)
+         pm.this.verbose = 1;
+
+      else if (strcmp(*argv, "-l") == 0)
+         pm.log = 1;
+
+      else if (strcmp(*argv, "-q") == 0)
+         summary = pm.this.verbose = pm.log = 0;
+
+      else if (strcmp(*argv, "-w") == 0)
+         pm.this.treat_warnings_as_errors = 0;
+
+      else if (strcmp(*argv, "--speed") == 0)
+         pm.this.speed = 1, pm.ngamma_tests = pm.ngammas, pm.test_standard = 0,
+            summary = 0;
+
+      else if (strcmp(*argv, "--memory") == 0)
+         memstats = 1;
+
+      else if (strcmp(*argv, "--size") == 0)
+         pm.test_size = 1;
+
+      else if (strcmp(*argv, "--nosize") == 0)
+         pm.test_size = 0;
+
+      else if (strcmp(*argv, "--standard") == 0)
+         pm.test_standard = 1;
+
+      else if (strcmp(*argv, "--nostandard") == 0)
+         pm.test_standard = 0;
+
+      else if (strcmp(*argv, "--transform") == 0)
+         pm.test_transform = 1;
+
+      else if (strcmp(*argv, "--notransform") == 0)
+         pm.test_transform = 0;
+
+#ifdef PNG_READ_TRANSFORMS_SUPPORTED
+      else if (strncmp(*argv, "--transform-disable=",
+         sizeof "--transform-disable") == 0)
+         {
+         pm.test_transform = 1;
+         transform_disable(*argv + sizeof "--transform-disable");
+         }
+
+      else if (strncmp(*argv, "--transform-enable=",
+         sizeof "--transform-enable") == 0)
+         {
+         pm.test_transform = 1;
+         transform_enable(*argv + sizeof "--transform-enable");
+         }
+#endif /* PNG_READ_TRANSFORMS_SUPPORTED */
+
+      else if (strcmp(*argv, "--gamma") == 0)
+         {
+         /* Just do two gamma tests here (2.2 and linear) for speed: */
+         pm.ngamma_tests = 2U;
+         pm.test_gamma_threshold = 1;
+         pm.test_gamma_transform = 1;
+         pm.test_gamma_sbit = 1;
+         pm.test_gamma_scale16 = 1;
+         pm.test_gamma_background = 1;
+         pm.test_gamma_alpha_mode = 1;
+         }
+
+      else if (strcmp(*argv, "--nogamma") == 0)
+         pm.ngamma_tests = 0;
+
+      else if (strcmp(*argv, "--gamma-threshold") == 0)
+         pm.ngamma_tests = 2U, pm.test_gamma_threshold = 1;
+
+      else if (strcmp(*argv, "--nogamma-threshold") == 0)
+         pm.test_gamma_threshold = 0;
+
+      else if (strcmp(*argv, "--gamma-transform") == 0)
+         pm.ngamma_tests = 2U, pm.test_gamma_transform = 1;
+
+      else if (strcmp(*argv, "--nogamma-transform") == 0)
+         pm.test_gamma_transform = 0;
+
+      else if (strcmp(*argv, "--gamma-sbit") == 0)
+         pm.ngamma_tests = 2U, pm.test_gamma_sbit = 1;
+
+      else if (strcmp(*argv, "--nogamma-sbit") == 0)
+         pm.test_gamma_sbit = 0;
+
+      else if (strcmp(*argv, "--gamma-16-to-8") == 0)
+         pm.ngamma_tests = 2U, pm.test_gamma_scale16 = 1;
+
+      else if (strcmp(*argv, "--nogamma-16-to-8") == 0)
+         pm.test_gamma_scale16 = 0;
+
+      else if (strcmp(*argv, "--gamma-background") == 0)
+         pm.ngamma_tests = 2U, pm.test_gamma_background = 1;
+
+      else if (strcmp(*argv, "--nogamma-background") == 0)
+         pm.test_gamma_background = 0;
+
+      else if (strcmp(*argv, "--gamma-alpha-mode") == 0)
+         pm.ngamma_tests = 2U, pm.test_gamma_alpha_mode = 1;
+
+      else if (strcmp(*argv, "--nogamma-alpha-mode") == 0)
+         pm.test_gamma_alpha_mode = 0;
+
+      else if (strcmp(*argv, "--expand16") == 0)
+         pm.test_gamma_expand16 = 1;
+
+      else if (strcmp(*argv, "--noexpand16") == 0)
+         pm.test_gamma_expand16 = 0;
+
+      else if (strcmp(*argv, "--more-gammas") == 0)
+         pm.ngamma_tests = 3U;
+
+      else if (strcmp(*argv, "--all-gammas") == 0)
+         pm.ngamma_tests = pm.ngammas;
+
+      else if (strcmp(*argv, "--progressive-read") == 0)
+         pm.this.progressive = 1;
+
+      else if (strcmp(*argv, "--use-update-info") == 0)
+         ++pm.use_update_info; /* Can call multiple times */
+
+      else if (strcmp(*argv, "--interlace") == 0)
+         pm.interlace_type = PNG_INTERLACE_ADAM7;
+
+      else if (strcmp(*argv, "--use-input-precision") == 0)
+         pm.use_input_precision = 1;
+
+      else if (strcmp(*argv, "--calculations-use-input-precision") == 0)
+         pm.calculations_use_input_precision = 1;
+
+      else if (strcmp(*argv, "--assume-16-bit-calculations") == 0)
+         pm.assume_16_bit_calculations = 1;
+
+      else if (strcmp(*argv, "--calculations-follow-bit-depth") == 0)
+         pm.calculations_use_input_precision =
+            pm.assume_16_bit_calculations = 0;
+
+      else if (strcmp(*argv, "--exhaustive") == 0)
+         pm.test_exhaustive = 1;
+
+      else if (argc > 1 && strcmp(*argv, "--sbitlow") == 0)
+         --argc, pm.sbitlow = (png_byte)atoi(*++argv), catmore = 1;
+
+      else if (argc > 1 && strcmp(*argv, "--touch") == 0)
+         --argc, touch = *++argv, catmore = 1;
+
+      else if (argc > 1 && strncmp(*argv, "--max", 5) == 0)
+      {
+         --argc;
+
+         if (strcmp(5+*argv, "abs8") == 0)
+            pm.maxabs8 = atof(*++argv);
+
+         else if (strcmp(5+*argv, "abs16") == 0)
+            pm.maxabs16 = atof(*++argv);
+
+         else if (strcmp(5+*argv, "calc8") == 0)
+            pm.maxcalc8 = atof(*++argv);
+
+         else if (strcmp(5+*argv, "calc16") == 0)
+            pm.maxcalc16 = atof(*++argv);
+
+         else if (strcmp(5+*argv, "out8") == 0)
+            pm.maxout8 = atof(*++argv);
+
+         else if (strcmp(5+*argv, "out16") == 0)
+            pm.maxout16 = atof(*++argv);
+
+         else if (strcmp(5+*argv, "pc8") == 0)
+            pm.maxpc8 = atof(*++argv);
+
+         else if (strcmp(5+*argv, "pc16") == 0)
+            pm.maxpc16 = atof(*++argv);
+
+         else
+         {
+            fprintf(stderr, "pngvalid: %s: unknown 'max' option\n", *argv);
+            exit(1);
+         }
+
+         catmore = 1;
+      }
+
+      else if (strcmp(*argv, "--log8") == 0)
+         --argc, pm.log8 = atof(*++argv), catmore = 1;
+
+      else if (strcmp(*argv, "--log16") == 0)
+         --argc, pm.log16 = atof(*++argv), catmore = 1;
+
+      else
+      {
+         fprintf(stderr, "pngvalid: %s: unknown argument\n", *argv);
+         exit(1);
+      }
+
+      if (catmore) /* consumed an extra *argv */
+      {
+         cp = safecat(command, sizeof command, cp, " ");
+         cp = safecat(command, sizeof command, cp, *argv);
+      }
+   }
+
+   /* If pngvalid is run with no arguments default to a reasonable set of the
+    * tests.
+    */
+   if (pm.test_standard == 0 && pm.test_size == 0 && pm.test_transform == 0 &&
+      pm.ngamma_tests == 0)
+   {
+      /* Make this do all the tests done in the test shell scripts with the same
+       * parameters, where possible.  The limitation is that all the progressive
+       * read and interlace stuff has to be done in separate runs, so only the
+       * basic 'standard' and 'size' tests are done.
+       */
+      pm.test_standard = 1;
+      pm.test_size = 1;
+      pm.test_transform = 1;
+      pm.ngamma_tests = 2U;
+   }
+
+   if (pm.ngamma_tests > 0 &&
+      pm.test_gamma_threshold == 0 && pm.test_gamma_transform == 0 &&
+      pm.test_gamma_sbit == 0 && pm.test_gamma_scale16 == 0 &&
+      pm.test_gamma_background == 0 && pm.test_gamma_alpha_mode == 0)
+   {
+      pm.test_gamma_threshold = 1;
+      pm.test_gamma_transform = 1;
+      pm.test_gamma_sbit = 1;
+      pm.test_gamma_scale16 = 1;
+      pm.test_gamma_background = 1;
+      pm.test_gamma_alpha_mode = 1;
+   }
+
+   else if (pm.ngamma_tests == 0)
+   {
+      /* Nothing to test so turn everything off: */
+      pm.test_gamma_threshold = 0;
+      pm.test_gamma_transform = 0;
+      pm.test_gamma_sbit = 0;
+      pm.test_gamma_scale16 = 0;
+      pm.test_gamma_background = 0;
+      pm.test_gamma_alpha_mode = 0;
+   }
+
+   Try
+   {
+      /* Make useful base images */
+      make_transform_images(&pm.this);
+
+      /* Perform the standard and gamma tests. */
+      if (pm.test_standard)
+      {
+         perform_interlace_macro_validation();
+         perform_formatting_test(&pm.this);
+         perform_standard_test(&pm);
+         perform_error_test(&pm);
+      }
+
+      /* Various oddly sized images: */
+      if (pm.test_size)
+      {
+         make_size_images(&pm.this);
+         perform_size_test(&pm);
+      }
+
+#ifdef PNG_READ_TRANSFORMS_SUPPORTED
+      /* Combinatorial transforms: */
+      if (pm.test_transform)
+         perform_transform_test(&pm);
+#endif /* PNG_READ_TRANSFORMS_SUPPORTED */
+
+#ifdef PNG_READ_GAMMA_SUPPORTED
+      if (pm.ngamma_tests > 0)
+         perform_gamma_test(&pm, summary);
+#endif
+   }
+
+   Catch_anonymous
+   {
+      fprintf(stderr, "pngvalid: test aborted (probably failed in cleanup)\n");
+      if (!pm.this.verbose)
+      {
+         if (pm.this.error[0] != 0)
+            fprintf(stderr, "pngvalid: first error: %s\n", pm.this.error);
+
+         fprintf(stderr, "pngvalid: run with -v to see what happened\n");
+      }
+      exit(1);
+   }
+
+   if (summary)
+   {
+      printf("%s: %s (%s point arithmetic)\n",
+         (pm.this.nerrors || (pm.this.treat_warnings_as_errors &&
+            pm.this.nwarnings)) ? "FAIL" : "PASS",
+         command,
+#if defined(PNG_FLOATING_ARITHMETIC_SUPPORTED) || PNG_LIBPNG_VER < 10500
+         "floating"
+#else
+         "fixed"
+#endif
+         );
+   }
+
+   if (memstats)
+   {
+      printf("Allocated memory statistics (in bytes):\n"
+         "\tread  %lu maximum single, %lu peak, %lu total\n"
+         "\twrite %lu maximum single, %lu peak, %lu total\n",
+         (unsigned long)pm.this.read_memory_pool.max_max,
+         (unsigned long)pm.this.read_memory_pool.max_limit,
+         (unsigned long)pm.this.read_memory_pool.max_total,
+         (unsigned long)pm.this.write_memory_pool.max_max,
+         (unsigned long)pm.this.write_memory_pool.max_limit,
+         (unsigned long)pm.this.write_memory_pool.max_total);
+   }
+
+   /* Do this here to provoke memory corruption errors in memory not directly
+    * allocated by libpng - not a complete test, but better than nothing.
+    */
+   store_delete(&pm.this);
+
+   /* Error exit if there are any errors, and maybe if there are any
+    * warnings.
+    */
+   if (pm.this.nerrors || (pm.this.treat_warnings_as_errors &&
+       pm.this.nwarnings))
+   {
+      if (!pm.this.verbose)
+         fprintf(stderr, "pngvalid: %s\n", pm.this.error);
+
+      fprintf(stderr, "pngvalid: %d errors, %d warnings\n", pm.this.nerrors,
+          pm.this.nwarnings);
+
+      exit(1);
+   }
+
+   /* Success case. */
+   if (touch != NULL)
+   {
+      FILE *fsuccess = fopen(touch, "wt");
+
+      if (fsuccess != NULL)
+      {
+         int error = 0;
+         fprintf(fsuccess, "PNG validation succeeded\n");
+         fflush(fsuccess);
+         error = ferror(fsuccess);
+
+         if (fclose(fsuccess) || error)
+         {
+            fprintf(stderr, "%s: write failed\n", touch);
+            exit(1);
+         }
+      }
+   }
+
+   return 0;
+}
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/decoder/README b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/decoder/README
index 86583cc..fa979fc 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/decoder/README
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/decoder/README
@@ -1,10 +1,10 @@
-This demonstrates the use of PNG_USER_CONFIG, pngusr.h and pngusr.dfa

-

-The makefile builds a minimal read-only decoder with embedded libpng

-and zlib.

-

-Specify the location of the zlib source (1.2.1 or later) as ZLIBSRC

-on the make command line.

-

-If you prefer to use the shared libraries, go to contrib/pngminus

-and build the png2pnm application there.

+This demonstrates the use of PNG_USER_CONFIG, pngusr.h and pngusr.dfa
+
+The makefile builds a minimal read-only decoder with embedded libpng
+and zlib.
+
+Specify the location of the zlib source (1.2.1 or later) as ZLIBSRC
+on the make command line.
+
+If you prefer to use the shared libraries, go to contrib/pngminus
+and build the png2pnm application there.
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/decoder/makefile b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/decoder/makefile
index 9692e0a..e10e122 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/decoder/makefile
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/decoder/makefile
@@ -1,150 +1,150 @@
-# Makefile for PngMinus (pngm2pnm)

-# Linux / Unix

-

-#CC=cc

-CC=gcc

-LD=$(CC)

-

-# If awk fails try

-# make AWK=nawk

-

-# If cpp fails try

-# make CPP=/lib/cpp

-

-RM=rm -f

-COPY=cp

-

-CFLAGS=-DPNG_USER_CONFIG -DNO_GZCOMPRESS -DNO_GZIP -I. -O1

-

-C=.c

-O=.o

-L=.a

-E=

-

-# Where to find the source code:

-PNGSRC =../../..

-ZLIBSRC=$(PNGSRC)/../zlib

-PROGSRC=$(PNGSRC)/contrib/pngminus

-

-# Zlib (minimal inflate requirements - crc32 is used by libpng)

-# zutil can be eliminated if you provide your own zcalloc and zcfree

-ZSRCS  = adler32$(C) crc32$(C) \

-         inffast$(C) inflate$(C) inftrees$(C) \

-         zutil$(C)

-

-# Standard headers

-ZH     = zlib.h crc32.h inffast.h inffixed.h \

-         inflate.h inftrees.h zutil.h

-

-# Machine generated headers

-ZCONF  = zconf.h

-

-# Headers callers use

-ZINC   = zlib.h $(ZCONF)

-

-# Headers the Zlib source uses

-ZHDRS  = $(ZH) $(ZCONF)

-

-ZOBJS  = adler32$(O) crc32$(O) \

-         inffast$(O) inflate$(O) inftrees$(O) \

-         zutil$(O)

-

-# libpng

-PNGSRCS=png$(C) pngerror$(C) pngget$(C) pngmem$(C) \

-        pngread$(C) pngrio$(C) pngrtran$(C) pngrutil$(C) \

-        pngset$(C) pngtrans$(C)

-        

-# Standard headers

-PNGH   =png.h pngconf.h pngdebug.h pnginfo.h pngpriv.h pngstruct.h

-

-# Machine generated headers

-PNGCONF=pnglibconf.h

-

-# Headers callers use

-PNGINC= png.h pngconf.h pngusr.h $(PNGCONF)

-

-# Headers the PNG library uses

-PNGHDRS=$(PNGH) $(PNGCONF) pngusr.h

-

-PNGOBJS=png$(O) pngerror$(O) pngget$(O) pngmem$(O) \

-        pngread$(O) pngrio$(O) pngrtran$(O) pngrutil$(O) \

-        pngset$(O) pngtrans$(O)

-

-PROGSRCS= pngm2pnm$(C)

-PROGHDRS=

-PROGDOCS=

-PROGOBJS= pngm2pnm$(O)

-

-OBJS    = $(PROGOBJS) $(PNGOBJS) $(ZOBJS)

-

-# implicit make rules -------------------------------------------------------

-

-# note: dependencies do not work on implicit rule lines

-.c$(O):

-        $(CC) -c $(CFLAGS) $<

-

-# dependencies

-

-all: pngm2pnm$(E)

-

-pngm2pnm$(E): $(OBJS)

-        $(LD) -o pngm2pnm$(E) $(OBJS)

-

-# The DFA_XTRA setting turns all libpng options off then

-# turns on those required for this minimal build.

-# The CPP_FLAGS setting causes pngusr.h to be included in

-# both the build of pnglibconf.h and, subsequently, when

-# building libpng itself.

-$(PNGCONF): $(PNGSRC)/scripts/pnglibconf.mak\

-        $(PNGSRC)/scripts/pnglibconf.dfa \

-        $(PNGSRC)/scripts/options.awk pngusr.h pngusr.dfa

-        $(RM) pnglibconf.h pnglibconf.dfn

-        $(MAKE) $(MAKEFLAGS) -f $(PNGSRC)/scripts/pnglibconf.mak\

-            srcdir=$(PNGSRC) CPPFLAGS="-DPNG_USER_CONFIG"\

-            DFA_XTRA="pngusr.dfa" $@

-

-clean:

-        $(MAKE) $(MAKEFLAGS) -f $(PNGSRC)/scripts/pnglibconf.mak\

-            srcdir=$(PNGSRC) clean

-        $(RM) pngm2pnm$(O)

-        $(RM) pngm2pnm$(E)

-        $(RM) $(OBJS)

-

-# distclean also removes the copied source and headers

-distclean: clean

-        $(RM) -r scripts # historical reasons

-        $(RM) $(PNGSRCS) $(PNGH)

-        $(RM) $(ZSRCS) $(ZH) $(ZCONF)

-        $(RM) $(PROGSRCS) $(PROGHDRS) $(PROGDOCS)

-

-# Header file dependencies:

-$(PROGOBJS): $(PROGHDRS) $(PNGINC) $(ZINC)

-$(PNGOBJS): $(PNGHDRS) $(ZINC)

-$(ZOBJS): $(ZHDRS)

-

-# Gather the source code from the respective directories

-$(PNGSRCS) $(PNGH): $(PNGSRC)/$@

-        $(RM) $@

-        $(COPY) $(PNGSRC)/$@ $@

-

-# No dependency on the ZLIBSRC target so that it only needs

-# to be specified once.

-$(ZSRCS) $(ZH):

-        $(RM) $@

-        $(COPY) $(ZLIBSRC)/$@ $@

-

-# The unconfigured zconf.h varies in name according to the

-# zlib release

-$(ZCONF):

-        $(RM) $@

-        @for f in zconf.h.in zconf.in.h zconf.h; do\

-            test -r $(ZLIBSRC)/$$f &&\

-            echo $(COPY) $(ZLIBSRC)/$$f $@ &&\

-            $(COPY) $(ZLIBSRC)/$$f $@ && exit 0;\

-        done; echo copy: $(ZLIBSRC)/zconf.h not found; exit 1

-

-pngm2pnm.c: $(PROGSRC)/png2pnm.c

-        $(RM) $@

-        $(COPY) $(PROGSRC)/png2pnm.c $@

-

-# End of makefile for pngm2pnm

+# Makefile for PngMinus (pngm2pnm)
+# Linux / Unix
+
+#CC=cc
+CC=gcc
+LD=$(CC)
+
+# If awk fails try
+# make AWK=nawk
+
+# If cpp fails try
+# make CPP=/lib/cpp
+
+RM=rm -f
+COPY=cp
+
+CFLAGS=-DPNG_USER_CONFIG -DNO_GZCOMPRESS -DNO_GZIP -I. -O1
+
+C=.c
+O=.o
+L=.a
+E=
+
+# Where to find the source code:
+PNGSRC =../../..
+ZLIBSRC=$(PNGSRC)/../zlib
+PROGSRC=$(PNGSRC)/contrib/pngminus
+
+# Zlib (minimal inflate requirements - crc32 is used by libpng)
+# zutil can be eliminated if you provide your own zcalloc and zcfree
+ZSRCS  = adler32$(C) crc32$(C) \
+         inffast$(C) inflate$(C) inftrees$(C) \
+         zutil$(C)
+
+# Standard headers
+ZH     = zlib.h crc32.h inffast.h inffixed.h \
+         inflate.h inftrees.h zutil.h
+
+# Machine generated headers
+ZCONF  = zconf.h
+
+# Headers callers use
+ZINC   = zlib.h $(ZCONF)
+
+# Headers the Zlib source uses
+ZHDRS  = $(ZH) $(ZCONF)
+
+ZOBJS  = adler32$(O) crc32$(O) \
+         inffast$(O) inflate$(O) inftrees$(O) \
+         zutil$(O)
+
+# libpng
+PNGSRCS=png$(C) pngerror$(C) pngget$(C) pngmem$(C) \
+        pngread$(C) pngrio$(C) pngrtran$(C) pngrutil$(C) \
+        pngset$(C) pngtrans$(C)
+        
+# Standard headers
+PNGH   =png.h pngconf.h pngdebug.h pnginfo.h pngpriv.h pngstruct.h
+
+# Machine generated headers
+PNGCONF=pnglibconf.h
+
+# Headers callers use
+PNGINC= png.h pngconf.h pngusr.h $(PNGCONF)
+
+# Headers the PNG library uses
+PNGHDRS=$(PNGH) $(PNGCONF) pngusr.h
+
+PNGOBJS=png$(O) pngerror$(O) pngget$(O) pngmem$(O) \
+        pngread$(O) pngrio$(O) pngrtran$(O) pngrutil$(O) \
+        pngset$(O) pngtrans$(O)
+
+PROGSRCS= pngm2pnm$(C)
+PROGHDRS=
+PROGDOCS=
+PROGOBJS= pngm2pnm$(O)
+
+OBJS    = $(PROGOBJS) $(PNGOBJS) $(ZOBJS)
+
+# implicit make rules -------------------------------------------------------
+
+# note: dependencies do not work on implicit rule lines
+.c$(O):
+        $(CC) -c $(CFLAGS) $<
+
+# dependencies
+
+all: pngm2pnm$(E)
+
+pngm2pnm$(E): $(OBJS)
+        $(LD) -o pngm2pnm$(E) $(OBJS)
+
+# The DFA_XTRA setting turns all libpng options off then
+# turns on those required for this minimal build.
+# The CPP_FLAGS setting causes pngusr.h to be included in
+# both the build of pnglibconf.h and, subsequently, when
+# building libpng itself.
+$(PNGCONF): $(PNGSRC)/scripts/pnglibconf.mak\
+        $(PNGSRC)/scripts/pnglibconf.dfa \
+        $(PNGSRC)/scripts/options.awk pngusr.h pngusr.dfa
+        $(RM) pnglibconf.h pnglibconf.dfn
+        $(MAKE) $(MAKEFLAGS) -f $(PNGSRC)/scripts/pnglibconf.mak\
+            srcdir=$(PNGSRC) CPPFLAGS="-DPNG_USER_CONFIG"\
+            DFA_XTRA="pngusr.dfa" $@
+
+clean:
+        $(MAKE) $(MAKEFLAGS) -f $(PNGSRC)/scripts/pnglibconf.mak\
+            srcdir=$(PNGSRC) clean
+        $(RM) pngm2pnm$(O)
+        $(RM) pngm2pnm$(E)
+        $(RM) $(OBJS)
+
+# distclean also removes the copied source and headers
+distclean: clean
+        $(RM) -r scripts # historical reasons
+        $(RM) $(PNGSRCS) $(PNGH)
+        $(RM) $(ZSRCS) $(ZH) $(ZCONF)
+        $(RM) $(PROGSRCS) $(PROGHDRS) $(PROGDOCS)
+
+# Header file dependencies:
+$(PROGOBJS): $(PROGHDRS) $(PNGINC) $(ZINC)
+$(PNGOBJS): $(PNGHDRS) $(ZINC)
+$(ZOBJS): $(ZHDRS)
+
+# Gather the source code from the respective directories
+$(PNGSRCS) $(PNGH): $(PNGSRC)/$@
+        $(RM) $@
+        $(COPY) $(PNGSRC)/$@ $@
+
+# No dependency on the ZLIBSRC target so that it only needs
+# to be specified once.
+$(ZSRCS) $(ZH):
+        $(RM) $@
+        $(COPY) $(ZLIBSRC)/$@ $@
+
+# The unconfigured zconf.h varies in name according to the
+# zlib release
+$(ZCONF):
+        $(RM) $@
+        @for f in zconf.h.in zconf.in.h zconf.h; do\
+            test -r $(ZLIBSRC)/$$f &&\
+            echo $(COPY) $(ZLIBSRC)/$$f $@ &&\
+            $(COPY) $(ZLIBSRC)/$$f $@ && exit 0;\
+        done; echo copy: $(ZLIBSRC)/zconf.h not found; exit 1
+
+pngm2pnm.c: $(PROGSRC)/png2pnm.c
+        $(RM) $@
+        $(COPY) $(PROGSRC)/png2pnm.c $@
+
+# End of makefile for pngm2pnm
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/decoder/pngusr.dfa b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/decoder/pngusr.dfa
index 8a66d64..70d528b 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/decoder/pngusr.dfa
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/decoder/pngusr.dfa
@@ -1,39 +1,39 @@
-# pngminim/decoder/pngusr.dfa

-#

-# Copyright (c) 2010-2011 Glenn Randers-Pehrson

-#

-# This code is released under the libpng license.

-# For conditions of distribution and use, see the disclaimer

-# and license in png.h

-

-# First all the build options off:

-

-everything = off

-

-# All that is required is some read code. This example switches

-# on the sequential read code (see ../preader for a progressive

-# read example).

-

-option SEQUENTIAL_READ on

-

-# You must choose fixed or floating point arithmetic:

-# option FLOATING_POINT on

-

-option FIXED_POINT on

-

-# You must chose the internal fixed point implementation or to

-# use the system floating point.  The latter is considerably

-# smaller (by about 1kbyte on an x86 system):

-# option FLOATING_ARITHMETIC on

-

-option FLOATING_ARITHMETIC off

-

-# Your program will probably need other options.  The example

-# program here, pngm2pnm, requires the following.  Take a look

-# at pnglibconf.h to find out the full set of what has to be

-# enabled to make the following work.

-

-option SETJMP on

-option STDIO on

-option READ_EXPAND on

-option READ_STRIP_16_TO_8 on

+# pngminim/decoder/pngusr.dfa
+#
+# Copyright (c) 2010-2011 Glenn Randers-Pehrson
+#
+# This code is released under the libpng license.
+# For conditions of distribution and use, see the disclaimer
+# and license in png.h
+
+# First all the build options off:
+
+everything = off
+
+# All that is required is some read code. This example switches
+# on the sequential read code (see ../preader for a progressive
+# read example).
+
+option SEQUENTIAL_READ on
+
+# You must choose fixed or floating point arithmetic:
+# option FLOATING_POINT on
+
+option FIXED_POINT on
+
+# You must chose the internal fixed point implementation or to
+# use the system floating point.  The latter is considerably
+# smaller (by about 1kbyte on an x86 system):
+# option FLOATING_ARITHMETIC on
+
+option FLOATING_ARITHMETIC off
+
+# Your program will probably need other options.  The example
+# program here, pngm2pnm, requires the following.  Take a look
+# at pnglibconf.h to find out the full set of what has to be
+# enabled to make the following work.
+
+option SETJMP on
+option STDIO on
+option READ_EXPAND on
+option READ_STRIP_16_TO_8 on
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/decoder/pngusr.h b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/decoder/pngusr.h
index 2991c17..9d9c50c 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/decoder/pngusr.h
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/decoder/pngusr.h
@@ -1,24 +1,24 @@
-/* minrdpngconf.h: headers to make a minimal png-read-only library

- *

- * Copyright (c) 2007, 2010-2011 Glenn Randers-Pehrson

- *

- * This code is released under the libpng license.

- * For conditions of distribution and use, see the disclaimer

- * and license in png.h

- *

- * Derived from pngcrush.h, Copyright 1998-2007, Glenn Randers-Pehrson

- */

-

-#ifndef MINRDPNGCONF_H

-#define MINRDPNGCONF_H

-

-/* To include pngusr.h set -DPNG_USER_CONFIG in CPPFLAGS */

-

-/* List options to turn off features of the build that do not

- * affect the API (so are not recorded in pnglibconf.h)

- */

-

-#define PNG_NO_WARNINGS

-#define PNG_ALIGN_TYPE PNG_ALIGN_NONE

-

-#endif /* MINRDPNGCONF_H */

+/* minrdpngconf.h: headers to make a minimal png-read-only library
+ *
+ * Copyright (c) 2007, 2010-2011 Glenn Randers-Pehrson
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ *
+ * Derived from pngcrush.h, Copyright 1998-2007, Glenn Randers-Pehrson
+ */
+
+#ifndef MINRDPNGCONF_H
+#define MINRDPNGCONF_H
+
+/* To include pngusr.h set -DPNG_USER_CONFIG in CPPFLAGS */
+
+/* List options to turn off features of the build that do not
+ * affect the API (so are not recorded in pnglibconf.h)
+ */
+
+#define PNG_NO_WARNINGS
+#define PNG_ALIGN_TYPE PNG_ALIGN_NONE
+
+#endif /* MINRDPNGCONF_H */
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/encoder/README b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/encoder/README
index f8a8b6d..ff9aa45 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/encoder/README
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/encoder/README
@@ -1,10 +1,10 @@
-This demonstrates the use of PNG_USER_CONFIG and pngusr.h

-

-The makefile builds a minimal write-only decoder with embedded libpng

-and zlib.

-

-Specify the location of the zlib source (1.2.1 or later) as ZLIBSRC

-on the make command line.

-

-If you prefer to use the shared libraries, go to contrib/pngminus

-and build the pnm2png application there.

+This demonstrates the use of PNG_USER_CONFIG and pngusr.h
+
+The makefile builds a minimal write-only decoder with embedded libpng
+and zlib.
+
+Specify the location of the zlib source (1.2.1 or later) as ZLIBSRC
+on the make command line.
+
+If you prefer to use the shared libraries, go to contrib/pngminus
+and build the pnm2png application there.
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/encoder/makefile b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/encoder/makefile
index 7374a6c..d6f39e2 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/encoder/makefile
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/encoder/makefile
@@ -1,149 +1,149 @@
-# Makefile for PngMinus (pnm2pngm)

-# Linux / Unix

-

-#CC=cc

-CC=gcc

-LD=$(CC)

-

-# If awk fails try

-# make AWK=nawk

-

-# If cpp fails try

-# make CPP=/lib/cpp

-

-RM=rm -f

-COPY=cp

-

-CFLAGS=-DPNG_USER_CONFIG -DNO_GZIP -I. -O1

-

-C=.c

-O=.o

-L=.a

-E=

-

-# Where to find the source code:

-PNGSRC =../../..

-ZLIBSRC=$(PNGSRC)/../zlib

-PROGSRC=$(PNGSRC)/contrib/pngminus

-

-# Zlib

-ZSRCS  = adler32$(C) compress$(C) crc32$(C) deflate$(C) \

-         trees$(C) zutil$(C)

-

-# Standard headers

-#ZH     = zlib.h crc32.h deflate.h trees.h zutil.h

-ZH     = zlib.h crc32.h deflate.h trees.h zutil.h

-

-# Machine generated headers

-ZCONF  = zconf.h

-

-# Headers callers use

-ZINC   = zlib.h $(ZCONF)

-

-# Headers the Zlib source uses

-ZHDRS  = $(ZH) $(ZCONF)

-

-# compress is not required; it is needed to link the zlib

-# code because deflate defines an unused API function deflateBound

-# which itself calls compressBound from compress.

-ZOBJS  = adler32$(O) compress$(O) crc32$(O) deflate$(O) \

-         trees$(O) zutil$(O)

-

-# libpng

-PNGSRCS=png$(C) pngerror$(C) pngget$(C) pngmem$(C) \

-        pngset$(C) pngtrans$(C) pngwio$(C) pngwrite$(C) \

-        pngwtran$(C) pngwutil$(C)

-

-# Standard headers

-PNGH   =png.h pngconf.h pngdebug.h pnginfo.h pngpriv.h pngstruct.h

-

-# Machine generated headers

-PNGCONF=pnglibconf.h

-

-# Headers callers use

-PNGINC= png.h pngconf.h pngusr.h $(PNGCONF)

-

-# Headers the PNG library uses

-PNGHDRS=$(PNGH) $(PNGCONF) pngusr.h

-

-PNGOBJS=png$(O) pngerror$(O) pngget$(O) pngmem$(O) \

-        pngset$(O) pngtrans$(O) pngwio$(O) pngwrite$(O) \

-        pngwtran$(O) pngwutil$(O)

-

-PROGSRCS= pnm2pngm$(C)

-PROGHDRS=

-PROGDOCS=

-PROGOBJS= pnm2pngm$(O)

-

-OBJS    = $(PROGOBJS) $(PNGOBJS) $(ZOBJS)

-

-# implicit make rules -------------------------------------------------------

-

-.c$(O):

-        $(CC) -c $(CFLAGS) $<

-

-# dependencies

-

-all: pnm2pngm$(E)

-

-pnm2pngm$(E): $(OBJS)

-        $(LD) -o pnm2pngm$(E) $(OBJS)

-

-# The DFA_XTRA setting turns all libpng options off then

-# turns on those required for this minimal build.

-# The CPP_FLAGS setting causes pngusr.h to be included in

-# both the build of pnglibconf.h and, subsequently, when

-# building libpng itself.

-$(PNGCONF): $(PNGSRC)/scripts/pnglibconf.mak\

-        $(PNGSRC)/scripts/pnglibconf.dfa \

-        $(PNGSRC)/scripts/options.awk pngusr.h pngusr.dfa

-        $(RM) pnglibconf.h pnglibconf.dfn

-        $(MAKE) $(MAKEFLAGS) -f $(PNGSRC)/scripts/pnglibconf.mak\

-            srcdir=$(PNGSRC) CPPFLAGS="-DPNG_USER_CONFIG"\

-            DFA_XTRA="pngusr.dfa" $@

-

-clean:

-        $(MAKE) $(MAKEFLAGS) -f $(PNGSRC)/scripts/pnglibconf.mak\

-            srcdir=$(PNGSRC) clean

-        $(RM) pnm2pngm$(O)

-        $(RM) pnm2pngm$(E)

-        $(RM) $(OBJS)

-

-# distclean also removes the copied source and headers

-distclean: clean

-        $(RM) -r scripts # historical reasons

-        $(RM) $(PNGSRCS) $(PNGH)

-        $(RM) $(ZSRCS) $(ZH) $(ZCONF)

-        $(RM) $(PROGSRCS) $(PROGHDRS) $(PROGDOCS)

-

-# Header file dependencies:

-$(PROGOBJS): $(PROGHDRS) $(PNGINC) $(ZINC)

-$(PNGOBJS): $(PNGHDRS) $(ZINC)

-$(ZOBJS): $(ZHDRS)

-

-# Gather the source code from the respective directories

-$(PNGSRCS) $(PNGH): $(PNGSRC)/$@

-        $(RM) $@

-        $(COPY) $(PNGSRC)/$@ $@

-

-# No dependency on the ZLIBSRC target so that it only needs

-# to be specified once.

-$(ZSRCS) $(ZH):

-        $(RM) $@

-        $(COPY) $(ZLIBSRC)/$@ $@

-

-# The unconfigured zconf.h varies in name according to the

-# zlib release

-$(ZCONF):

-        $(RM) $@

-        @for f in zconf.h.in zconf.in.h zconf.h; do\

-            test -r $(ZLIBSRC)/$$f &&\

-            echo $(COPY) $(ZLIBSRC)/$$f $@ &&\

-            $(COPY) $(ZLIBSRC)/$$f $@ && exit 0;\

-        done; echo copy: $(ZLIBSRC)/zconf.h not found; exit 1

-

-pnm2pngm.c: $(PROGSRC)/pnm2png.c

-        $(RM) $@

-        $(COPY) $(PROGSRC)/pnm2png.c $@

-

-# End of makefile for pnm2pngm

+# Makefile for PngMinus (pnm2pngm)
+# Linux / Unix
+
+#CC=cc
+CC=gcc
+LD=$(CC)
+
+# If awk fails try
+# make AWK=nawk
+
+# If cpp fails try
+# make CPP=/lib/cpp
+
+RM=rm -f
+COPY=cp
+
+CFLAGS=-DPNG_USER_CONFIG -DNO_GZIP -I. -O1
+
+C=.c
+O=.o
+L=.a
+E=
+
+# Where to find the source code:
+PNGSRC =../../..
+ZLIBSRC=$(PNGSRC)/../zlib
+PROGSRC=$(PNGSRC)/contrib/pngminus
+
+# Zlib
+ZSRCS  = adler32$(C) compress$(C) crc32$(C) deflate$(C) \
+         trees$(C) zutil$(C)
+
+# Standard headers
+#ZH     = zlib.h crc32.h deflate.h trees.h zutil.h
+ZH     = zlib.h crc32.h deflate.h trees.h zutil.h
+
+# Machine generated headers
+ZCONF  = zconf.h
+
+# Headers callers use
+ZINC   = zlib.h $(ZCONF)
+
+# Headers the Zlib source uses
+ZHDRS  = $(ZH) $(ZCONF)
+
+# compress is not required; it is needed to link the zlib
+# code because deflate defines an unused API function deflateBound
+# which itself calls compressBound from compress.
+ZOBJS  = adler32$(O) compress$(O) crc32$(O) deflate$(O) \
+         trees$(O) zutil$(O)
+
+# libpng
+PNGSRCS=png$(C) pngerror$(C) pngget$(C) pngmem$(C) \
+        pngset$(C) pngtrans$(C) pngwio$(C) pngwrite$(C) \
+        pngwtran$(C) pngwutil$(C)
+
+# Standard headers
+PNGH   =png.h pngconf.h pngdebug.h pnginfo.h pngpriv.h pngstruct.h
+
+# Machine generated headers
+PNGCONF=pnglibconf.h
+
+# Headers callers use
+PNGINC= png.h pngconf.h pngusr.h $(PNGCONF)
+
+# Headers the PNG library uses
+PNGHDRS=$(PNGH) $(PNGCONF) pngusr.h
+
+PNGOBJS=png$(O) pngerror$(O) pngget$(O) pngmem$(O) \
+        pngset$(O) pngtrans$(O) pngwio$(O) pngwrite$(O) \
+        pngwtran$(O) pngwutil$(O)
+
+PROGSRCS= pnm2pngm$(C)
+PROGHDRS=
+PROGDOCS=
+PROGOBJS= pnm2pngm$(O)
+
+OBJS    = $(PROGOBJS) $(PNGOBJS) $(ZOBJS)
+
+# implicit make rules -------------------------------------------------------
+
+.c$(O):
+        $(CC) -c $(CFLAGS) $<
+
+# dependencies
+
+all: pnm2pngm$(E)
+
+pnm2pngm$(E): $(OBJS)
+        $(LD) -o pnm2pngm$(E) $(OBJS)
+
+# The DFA_XTRA setting turns all libpng options off then
+# turns on those required for this minimal build.
+# The CPP_FLAGS setting causes pngusr.h to be included in
+# both the build of pnglibconf.h and, subsequently, when
+# building libpng itself.
+$(PNGCONF): $(PNGSRC)/scripts/pnglibconf.mak\
+        $(PNGSRC)/scripts/pnglibconf.dfa \
+        $(PNGSRC)/scripts/options.awk pngusr.h pngusr.dfa
+        $(RM) pnglibconf.h pnglibconf.dfn
+        $(MAKE) $(MAKEFLAGS) -f $(PNGSRC)/scripts/pnglibconf.mak\
+            srcdir=$(PNGSRC) CPPFLAGS="-DPNG_USER_CONFIG"\
+            DFA_XTRA="pngusr.dfa" $@
+
+clean:
+        $(MAKE) $(MAKEFLAGS) -f $(PNGSRC)/scripts/pnglibconf.mak\
+            srcdir=$(PNGSRC) clean
+        $(RM) pnm2pngm$(O)
+        $(RM) pnm2pngm$(E)
+        $(RM) $(OBJS)
+
+# distclean also removes the copied source and headers
+distclean: clean
+        $(RM) -r scripts # historical reasons
+        $(RM) $(PNGSRCS) $(PNGH)
+        $(RM) $(ZSRCS) $(ZH) $(ZCONF)
+        $(RM) $(PROGSRCS) $(PROGHDRS) $(PROGDOCS)
+
+# Header file dependencies:
+$(PROGOBJS): $(PROGHDRS) $(PNGINC) $(ZINC)
+$(PNGOBJS): $(PNGHDRS) $(ZINC)
+$(ZOBJS): $(ZHDRS)
+
+# Gather the source code from the respective directories
+$(PNGSRCS) $(PNGH): $(PNGSRC)/$@
+        $(RM) $@
+        $(COPY) $(PNGSRC)/$@ $@
+
+# No dependency on the ZLIBSRC target so that it only needs
+# to be specified once.
+$(ZSRCS) $(ZH):
+        $(RM) $@
+        $(COPY) $(ZLIBSRC)/$@ $@
+
+# The unconfigured zconf.h varies in name according to the
+# zlib release
+$(ZCONF):
+        $(RM) $@
+        @for f in zconf.h.in zconf.in.h zconf.h; do\
+            test -r $(ZLIBSRC)/$$f &&\
+            echo $(COPY) $(ZLIBSRC)/$$f $@ &&\
+            $(COPY) $(ZLIBSRC)/$$f $@ && exit 0;\
+        done; echo copy: $(ZLIBSRC)/zconf.h not found; exit 1
+
+pnm2pngm.c: $(PROGSRC)/pnm2png.c
+        $(RM) $@
+        $(COPY) $(PROGSRC)/pnm2png.c $@
+
+# End of makefile for pnm2pngm
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/encoder/pngusr.dfa b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/encoder/pngusr.dfa
index 448f821..ee88443 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/encoder/pngusr.dfa
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/encoder/pngusr.dfa
@@ -1,35 +1,35 @@
-# pngminim/encoder/pngusr.dfa

-#

-# Copyright (c) 2010-2011 Glenn Randers-Pehrson

-#

-# This code is released under the libpng license.

-# For conditions of distribution and use, see the disclaimer

-# and license in png.h

-

-# First all the build options off:

-

-everything = off

-

-# Switch on the write code - this makes a minimalist encoder

-

-option WRITE on

-

-# You must choose fixed or floating point arithmetic:

-# option FLOATING_POINT on

-

-option FIXED_POINT on

-

-# You must chose the internal fixed point implementation or to

-# use the system floating point.  The latter is considerably

-# smaller (by about 1kbyte on an x86 system):

-# option FLOATING_ARITHMETIC on

-

-option FLOATING_ARITHMETIC off

-

-# Your program will probably need other options.  The example

-# program here, pnm2pngm, requires the following.  Take a look

-# at pnglibconf.h to find out the full set of what has to be

-# enabled to make the following work.

-

-option SETJMP on

-option STDIO on

+# pngminim/encoder/pngusr.dfa
+#
+# Copyright (c) 2010-2011 Glenn Randers-Pehrson
+#
+# This code is released under the libpng license.
+# For conditions of distribution and use, see the disclaimer
+# and license in png.h
+
+# First all the build options off:
+
+everything = off
+
+# Switch on the write code - this makes a minimalist encoder
+
+option WRITE on
+
+# You must choose fixed or floating point arithmetic:
+# option FLOATING_POINT on
+
+option FIXED_POINT on
+
+# You must chose the internal fixed point implementation or to
+# use the system floating point.  The latter is considerably
+# smaller (by about 1kbyte on an x86 system):
+# option FLOATING_ARITHMETIC on
+
+option FLOATING_ARITHMETIC off
+
+# Your program will probably need other options.  The example
+# program here, pnm2pngm, requires the following.  Take a look
+# at pnglibconf.h to find out the full set of what has to be
+# enabled to make the following work.
+
+option SETJMP on
+option STDIO on
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/encoder/pngusr.h b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/encoder/pngusr.h
index bafbf13..2033aad 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/encoder/pngusr.h
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/encoder/pngusr.h
@@ -1,24 +1,24 @@
-/* minwrpngconf.h: headers to make a minimal png-write-only library

- *

- * Copyright (c) 2007, 2010-2011 Glenn Randers-Pehrson

- *

- * This code is released under the libpng license.

- * For conditions of distribution and use, see the disclaimer

- * and license in png.h

- *

- * Derived from pngcrush.h, Copyright 1998-2007, Glenn Randers-Pehrson

- */

-

-#ifndef MINWRPNGCONF_H

-#define MINWRPNGCONF_H

-

-/* To include pngusr.h set -DPNG_USER_CONFIG in CPPFLAGS */

-

-/* List options to turn off features of the build that do not

- * affect the API (so are not recorded in pnglibconf.h)

- */

-

-#define PNG_NO_WARNINGS

-#define PNG_ALIGN_TYPE PNG_ALIGN_NONE

-

-#endif /* MINWRPNGCONF_H */

+/* minwrpngconf.h: headers to make a minimal png-write-only library
+ *
+ * Copyright (c) 2007, 2010-2011 Glenn Randers-Pehrson
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ *
+ * Derived from pngcrush.h, Copyright 1998-2007, Glenn Randers-Pehrson
+ */
+
+#ifndef MINWRPNGCONF_H
+#define MINWRPNGCONF_H
+
+/* To include pngusr.h set -DPNG_USER_CONFIG in CPPFLAGS */
+
+/* List options to turn off features of the build that do not
+ * affect the API (so are not recorded in pnglibconf.h)
+ */
+
+#define PNG_NO_WARNINGS
+#define PNG_ALIGN_TYPE PNG_ALIGN_NONE
+
+#endif /* MINWRPNGCONF_H */
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/preader/README b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/preader/README
index e40024e..faa8356 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/preader/README
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/preader/README
@@ -1,15 +1,15 @@
-This demonstrates the use of PNG_USER_CONFIG and pngusr.h

-

-The makefile builds a minimal read-only progressive decoder with

-embedded libpng, zlib and your system's X library.

-

-Specify the location of the zlib source (1.2.1 or later) as ZLIBSRC

-on the make command line.

-

-Edit makefile if required, to find your X library and include files,

-then

-

-    make ZLIBSRC=directory

-

-If you prefer to use the shared libraries, go to contrib/gregbook

-and build the rpng2-x application there.

+This demonstrates the use of PNG_USER_CONFIG and pngusr.h
+
+The makefile builds a minimal read-only progressive decoder with
+embedded libpng, zlib and your system's X library.
+
+Specify the location of the zlib source (1.2.1 or later) as ZLIBSRC
+on the make command line.
+
+Edit makefile if required, to find your X library and include files,
+then
+
+    make ZLIBSRC=directory
+
+If you prefer to use the shared libraries, go to contrib/gregbook
+and build the rpng2-x application there.
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/preader/makefile b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/preader/makefile
index a367661..f4b0ccd 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/preader/makefile
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/preader/makefile
@@ -1,165 +1,165 @@
-# Makefile for PngMinus (rpng2)

-# Linux / Unix

-

-#CC=cc

-CC=gcc

-LD=$(CC)

-

-# If awk fails try

-# make AWK=nawk

-

-# If cpp fails try

-# make CPP=/lib/cpp

-

-RM=rm -f

-COPY=cp

-

-#XINC = -I/usr/include                  # old-style, stock X distributions

-#XLIB = -L/usr/lib/X11 -lX11            #  (including SGI IRIX)

-

-#XINC = -I/usr/openwin/include          # Sun workstations (OpenWindows)

-#XLIB = -L/usr/openwin/lib -lX11

-

-XINC = -I/usr/X11R6/include             # new X distributions (X.org, etc.)

-XLIB = -L/usr/X11R6/lib -lX11

-#XLIB = -L/usr/X11R6/lib64 -lX11        # e.g., Red Hat on AMD64

-

-#XINC = -I/usr/local/include            # FreeBSD

-#XLIB = -L/usr/local/lib -lX11

-

-#LIBS = $(XLIB)

-LIBS = $(XLIB) -lm                      #platforms that need libm

-

-CFLAGS=-DPNG_USER_CONFIG -DNO_GZCOMPRESS -DNO_GZIP -I. $(XINC) -O1

-

-C=.c

-O=.o

-L=.a

-E=

-

-# Where to find the source code:

-PNGSRC =../../..

-ZLIBSRC=$(PNGSRC)/../zlib

-PROGSRC=$(PNGSRC)/contrib/gregbook

-

-# Zlib (minimal inflate requirements - crc32 is used by libpng)

-# zutil can be eliminated if you provide your own zcalloc and zcfree

-ZSRCS  = adler32$(C) crc32$(C) \

-         inffast$(C) inflate$(C) inftrees$(C) \

-         zutil$(C)

-

-# Standard headers

-ZH     = zlib.h crc32.h inffast.h inffixed.h \

-         inflate.h inftrees.h zutil.h

-

-# Machine generated headers

-ZCONF  = zconf.h

-

-# Headers callers use

-ZINC   = zlib.h $(ZCONF)

-

-# Headers the Zlib source uses

-ZHDRS  = $(ZH) $(ZCONF)

-

-ZOBJS  = adler32$(O) crc32$(O) \

-         inffast$(O) inflate$(O) inftrees$(O) \

-         zutil$(O)

-

-# libpng

-PNGSRCS=png$(C) pngerror$(C) pngget$(C) pngmem$(C) \

-        pngpread$(C) pngread$(C) pngrio$(C) pngrtran$(C) pngrutil$(C) \

-        pngset$(C) pngtrans$(C)

-

-# Standard headers

-PNGH   =png.h pngconf.h pngdebug.h pnginfo.h pngpriv.h pngstruct.h

-

-# Machine generated headers

-PNGCONF=pnglibconf.h

-

-# Headers callers use

-PNGINC= png.h pngconf.h pngusr.h $(PNGCONF)

-

-# Headers the PNG library uses

-PNGHDRS=$(PNGH) $(PNGCONF) pngusr.h

-

-PNGOBJS=png$(O) pngerror$(O) pngget$(O) pngmem$(O) \

-        pngpread$(O) pngread$(O) pngrio$(O) pngrtran$(O) pngrutil$(O) \

-        pngset$(O) pngtrans$(O)

-

-PROGSRCS= rpng2-x$(C) readpng2$(C)

-PROGHDRS= readpng2.h

-PROGDOCS= COPYING LICENSE

-PROGOBJS= rpng2-x$(O) readpng2$(O)

-

-OBJS    = $(PROGOBJS) $(PNGOBJS) $(ZOBJS)

-

-# implicit make rules -------------------------------------------------------

-

-.c$(O):

-        $(CC) -c $(CFLAGS) $<

-

-# dependencies

-

-all: $(PROGDOCS) rpng2-x$(E)

-

-rpng2-x$(E): $(OBJS)

-        $(LD) -o rpng2-x$(E) $(OBJS) $(LIBS)

-

-# The DFA_XTRA setting turns all libpng options off then

-# turns on those required for this minimal build.

-# The CPP_FLAGS setting causes pngusr.h to be included in

-# both the build of pnglibconf.h and, subsequently, when

-# building libpng itself.

-$(PNGCONF): $(PNGSRC)/scripts/pnglibconf.mak\

-        $(PNGSRC)/scripts/pnglibconf.dfa \

-        $(PNGSRC)/scripts/options.awk pngusr.h pngusr.dfa

-        $(RM) pnglibconf.h pnglibconf.dfn

-        $(MAKE) $(MAKEFLAGS) -f $(PNGSRC)/scripts/pnglibconf.mak\

-            srcdir=$(PNGSRC) CPPFLAGS="-DPNG_USER_CONFIG"\

-            DFA_XTRA="pngusr.dfa" $@

-

-clean:

-        $(MAKE) $(MAKEFLAGS) -f $(PNGSRC)/scripts/pnglibconf.mak\

-            srcdir=$(PNGSRC) clean

-        $(RM) rpng2-x$(O)

-        $(RM) rpng2-x$(E)

-        $(RM) $(OBJS)

-

-# distclean also removes the copied source and headers

-distclean: clean

-        $(RM) -r scripts # historical reasons

-        $(RM) $(PNGSRCS) $(PNGH)

-        $(RM) $(ZSRCS) $(ZH) $(ZCONF)

-        $(RM) $(PROGSRCS) $(PROGHDRS) $(PROGDOCS)

-

-# Header file dependencies:

-$(PROGOBJS): $(PROGHDRS) $(PNGINC) $(ZINC)

-$(PNGOBJS): $(PNGHDRS) $(ZINC)

-$(ZOBJS): $(ZHDRS)

-

-# Gather the source code from the respective directories

-$(PNGSRCS) $(PNGH): $(PNGSRC)/$@

-        $(RM) $@

-        $(COPY) $(PNGSRC)/$@ $@

-

-# No dependency on the ZLIBSRC target so that it only needs

-# to be specified once.

-$(ZSRCS) $(ZH):

-        $(RM) $@

-        $(COPY) $(ZLIBSRC)/$@ $@

-

-# The unconfigured zconf.h varies in name according to the

-# zlib release

-$(ZCONF):

-        $(RM) $@

-        @for f in zconf.h.in zconf.in.h zconf.h; do\

-            test -r $(ZLIBSRC)/$$f &&\

-            echo $(COPY) $(ZLIBSRC)/$$f $@ &&\

-            $(COPY) $(ZLIBSRC)/$$f $@ && exit 0;\

-        done; echo copy: $(ZLIBSRC)/zconf.h not found; exit 1

-

-$(PROGSRCS) $(PROGHDRS) $(PROGDOCS): $(PROGSRC)/$@

-        $(RM) $@

-        $(COPY) $(PROGSRC)/$@ $@

-

-# End of makefile for rpng2-x

+# Makefile for PngMinus (rpng2)
+# Linux / Unix
+
+#CC=cc
+CC=gcc
+LD=$(CC)
+
+# If awk fails try
+# make AWK=nawk
+
+# If cpp fails try
+# make CPP=/lib/cpp
+
+RM=rm -f
+COPY=cp
+
+#XINC = -I/usr/include                  # old-style, stock X distributions
+#XLIB = -L/usr/lib/X11 -lX11            #  (including SGI IRIX)
+
+#XINC = -I/usr/openwin/include          # Sun workstations (OpenWindows)
+#XLIB = -L/usr/openwin/lib -lX11
+
+XINC = -I/usr/X11R6/include             # new X distributions (X.org, etc.)
+XLIB = -L/usr/X11R6/lib -lX11
+#XLIB = -L/usr/X11R6/lib64 -lX11        # e.g., Red Hat on AMD64
+
+#XINC = -I/usr/local/include            # FreeBSD
+#XLIB = -L/usr/local/lib -lX11
+
+#LIBS = $(XLIB)
+LIBS = $(XLIB) -lm                      #platforms that need libm
+
+CFLAGS=-DPNG_USER_CONFIG -DNO_GZCOMPRESS -DNO_GZIP -I. $(XINC) -O1
+
+C=.c
+O=.o
+L=.a
+E=
+
+# Where to find the source code:
+PNGSRC =../../..
+ZLIBSRC=$(PNGSRC)/../zlib
+PROGSRC=$(PNGSRC)/contrib/gregbook
+
+# Zlib (minimal inflate requirements - crc32 is used by libpng)
+# zutil can be eliminated if you provide your own zcalloc and zcfree
+ZSRCS  = adler32$(C) crc32$(C) \
+         inffast$(C) inflate$(C) inftrees$(C) \
+         zutil$(C)
+
+# Standard headers
+ZH     = zlib.h crc32.h inffast.h inffixed.h \
+         inflate.h inftrees.h zutil.h
+
+# Machine generated headers
+ZCONF  = zconf.h
+
+# Headers callers use
+ZINC   = zlib.h $(ZCONF)
+
+# Headers the Zlib source uses
+ZHDRS  = $(ZH) $(ZCONF)
+
+ZOBJS  = adler32$(O) crc32$(O) \
+         inffast$(O) inflate$(O) inftrees$(O) \
+         zutil$(O)
+
+# libpng
+PNGSRCS=png$(C) pngerror$(C) pngget$(C) pngmem$(C) \
+        pngpread$(C) pngread$(C) pngrio$(C) pngrtran$(C) pngrutil$(C) \
+        pngset$(C) pngtrans$(C)
+
+# Standard headers
+PNGH   =png.h pngconf.h pngdebug.h pnginfo.h pngpriv.h pngstruct.h
+
+# Machine generated headers
+PNGCONF=pnglibconf.h
+
+# Headers callers use
+PNGINC= png.h pngconf.h pngusr.h $(PNGCONF)
+
+# Headers the PNG library uses
+PNGHDRS=$(PNGH) $(PNGCONF) pngusr.h
+
+PNGOBJS=png$(O) pngerror$(O) pngget$(O) pngmem$(O) \
+        pngpread$(O) pngread$(O) pngrio$(O) pngrtran$(O) pngrutil$(O) \
+        pngset$(O) pngtrans$(O)
+
+PROGSRCS= rpng2-x$(C) readpng2$(C)
+PROGHDRS= readpng2.h
+PROGDOCS= COPYING LICENSE
+PROGOBJS= rpng2-x$(O) readpng2$(O)
+
+OBJS    = $(PROGOBJS) $(PNGOBJS) $(ZOBJS)
+
+# implicit make rules -------------------------------------------------------
+
+.c$(O):
+        $(CC) -c $(CFLAGS) $<
+
+# dependencies
+
+all: $(PROGDOCS) rpng2-x$(E)
+
+rpng2-x$(E): $(OBJS)
+        $(LD) -o rpng2-x$(E) $(OBJS) $(LIBS)
+
+# The DFA_XTRA setting turns all libpng options off then
+# turns on those required for this minimal build.
+# The CPP_FLAGS setting causes pngusr.h to be included in
+# both the build of pnglibconf.h and, subsequently, when
+# building libpng itself.
+$(PNGCONF): $(PNGSRC)/scripts/pnglibconf.mak\
+        $(PNGSRC)/scripts/pnglibconf.dfa \
+        $(PNGSRC)/scripts/options.awk pngusr.h pngusr.dfa
+        $(RM) pnglibconf.h pnglibconf.dfn
+        $(MAKE) $(MAKEFLAGS) -f $(PNGSRC)/scripts/pnglibconf.mak\
+            srcdir=$(PNGSRC) CPPFLAGS="-DPNG_USER_CONFIG"\
+            DFA_XTRA="pngusr.dfa" $@
+
+clean:
+        $(MAKE) $(MAKEFLAGS) -f $(PNGSRC)/scripts/pnglibconf.mak\
+            srcdir=$(PNGSRC) clean
+        $(RM) rpng2-x$(O)
+        $(RM) rpng2-x$(E)
+        $(RM) $(OBJS)
+
+# distclean also removes the copied source and headers
+distclean: clean
+        $(RM) -r scripts # historical reasons
+        $(RM) $(PNGSRCS) $(PNGH)
+        $(RM) $(ZSRCS) $(ZH) $(ZCONF)
+        $(RM) $(PROGSRCS) $(PROGHDRS) $(PROGDOCS)
+
+# Header file dependencies:
+$(PROGOBJS): $(PROGHDRS) $(PNGINC) $(ZINC)
+$(PNGOBJS): $(PNGHDRS) $(ZINC)
+$(ZOBJS): $(ZHDRS)
+
+# Gather the source code from the respective directories
+$(PNGSRCS) $(PNGH): $(PNGSRC)/$@
+        $(RM) $@
+        $(COPY) $(PNGSRC)/$@ $@
+
+# No dependency on the ZLIBSRC target so that it only needs
+# to be specified once.
+$(ZSRCS) $(ZH):
+        $(RM) $@
+        $(COPY) $(ZLIBSRC)/$@ $@
+
+# The unconfigured zconf.h varies in name according to the
+# zlib release
+$(ZCONF):
+        $(RM) $@
+        @for f in zconf.h.in zconf.in.h zconf.h; do\
+            test -r $(ZLIBSRC)/$$f &&\
+            echo $(COPY) $(ZLIBSRC)/$$f $@ &&\
+            $(COPY) $(ZLIBSRC)/$$f $@ && exit 0;\
+        done; echo copy: $(ZLIBSRC)/zconf.h not found; exit 1
+
+$(PROGSRCS) $(PROGHDRS) $(PROGDOCS): $(PROGSRC)/$@
+        $(RM) $@
+        $(COPY) $(PROGSRC)/$@ $@
+
+# End of makefile for rpng2-x
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/preader/pngusr.dfa b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/preader/pngusr.dfa
index 0c991d3..216c421 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/preader/pngusr.dfa
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/preader/pngusr.dfa
@@ -1,40 +1,40 @@
-# pngminim/preader/pngusr.dfa

-#

-# Copyright (c) 2010-2011 Glenn Randers-Pehrson

-#

-# This code is released under the libpng license.

-# For conditions of distribution and use, see the disclaimer

-# and license in png.h

-

-# First all the build options off:

-

-everything = off

-

-# Just switch on the progressive read code

-

-option PROGRESSIVE_READ on

-

-# You may choose fixed or floating point APIs:

-# option FLOATING_POINT on

-

-option FIXED_POINT on

-

-# You must chose the internal fixed point implementation or to

-# use the system floating point.  The latter is considerably

-# smaller (by about 1kbyte on an x86 system):

-

-option FLOATING_ARITHMETIC on

-# option FLOATING_ARITHMETIC off

-

-# Your program will probably need other options.  The example

-# program here, rpng2-x, requires the following.  Take a look

-# at pnglibconf.h to find out the full set of what has to be

-# enabled to make the following work.

-

-option SETJMP on

-option STDIO on

-option READ_bKGD on

-option READ_GAMMA on

-option READ_EXPAND on

-option READ_STRIP_16_TO_8 on

-option READ_GRAY_TO_RGB on

+# pngminim/preader/pngusr.dfa
+#
+# Copyright (c) 2010-2011 Glenn Randers-Pehrson
+#
+# This code is released under the libpng license.
+# For conditions of distribution and use, see the disclaimer
+# and license in png.h
+
+# First all the build options off:
+
+everything = off
+
+# Just switch on the progressive read code
+
+option PROGRESSIVE_READ on
+
+# You may choose fixed or floating point APIs:
+# option FLOATING_POINT on
+
+option FIXED_POINT on
+
+# You must chose the internal fixed point implementation or to
+# use the system floating point.  The latter is considerably
+# smaller (by about 1kbyte on an x86 system):
+
+option FLOATING_ARITHMETIC on
+# option FLOATING_ARITHMETIC off
+
+# Your program will probably need other options.  The example
+# program here, rpng2-x, requires the following.  Take a look
+# at pnglibconf.h to find out the full set of what has to be
+# enabled to make the following work.
+
+option SETJMP on
+option STDIO on
+option READ_bKGD on
+option READ_GAMMA on
+option READ_EXPAND on
+option READ_STRIP_16_TO_8 on
+option READ_GRAY_TO_RGB on
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/preader/pngusr.h b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/preader/pngusr.h
index 7db806f..73cfecf 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/preader/pngusr.h
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminim/preader/pngusr.h
@@ -1,24 +1,24 @@
-/* minrdpngconf.h: headers to make a minimal png-read-only library

- *

- * Copyright (c) 2009, 2010-2011 Glenn Randers-Pehrson

- *

- * This code is released under the libpng license.

- * For conditions of distribution and use, see the disclaimer

- * and license in png.h

- *

- * Derived from pngcrush.h, Copyright 1998-2007, Glenn Randers-Pehrson

- */

-

-#ifndef MINPRDPNGCONF_H

-#define MINPRDPNGCONF_H

-

-/* To include pngusr.h set -DPNG_USER_CONFIG in CPPFLAGS */

-

-/* List options to turn off features of the build that do not

- * affect the API (so are not recorded in pnglibconf.h)

- */

-

-#define PNG_NO_WARNINGS

-#define PNG_ALIGN_TYPE PNG_ALIGN_NONE

-

-#endif /* MINPRDPNGCONF_H */

+/* minrdpngconf.h: headers to make a minimal png-read-only library
+ *
+ * Copyright (c) 2009, 2010-2011 Glenn Randers-Pehrson
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ *
+ * Derived from pngcrush.h, Copyright 1998-2007, Glenn Randers-Pehrson
+ */
+
+#ifndef MINPRDPNGCONF_H
+#define MINPRDPNGCONF_H
+
+/* To include pngusr.h set -DPNG_USER_CONFIG in CPPFLAGS */
+
+/* List options to turn off features of the build that do not
+ * affect the API (so are not recorded in pnglibconf.h)
+ */
+
+#define PNG_NO_WARNINGS
+#define PNG_ALIGN_TYPE PNG_ALIGN_NONE
+
+#endif /* MINPRDPNGCONF_H */
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/README b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/README
index b0516ec..bbe7407 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/README
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/README
@@ -1,153 +1,153 @@
-PngMinus

---------

-(copyright Willem van Schaik, 1999)

-

-

-License

--------

-

-Permission to use, copy, modify, and distribute this software and

-its documentation for any purpose and without fee is hereby granted,

-provided that the above copyright notice appear in all copies and

-that both that copyright notice and this permission notice appear in

-supporting documentation. This software is provided "as is" without

-express or implied warranty.

-

-

-Some history

-------------

-Soon after the creation of PNG in 1995, the need was felt for a set of

-pnmtopng / pngtopnm utilities. Independantly Alexander Lehmann and I

-(Willem van Schaik) started such a project. Luckily we discovered this

-and merged the two together into pnmtopng.tar.gz, which is available

-from a/o ftp://ftp.simplesystems.org/pub/libpng/png/.

-

-These two utilities have many, many options and make use of most of the

-features of PNG, like gamma, alpha, sbit, text-chunks, etc. This makes

-the utilities quite complex and by now not anymore very maintainable.

-When we wrote these programs, libpng was still in an early stage.

-Therefore, lots of the functionality that we put in our software can now

-be done using transform-functions in libpng.

-

-Finally, to compile these programs, you need to have installed and

-compiled three libraries: libpng, zlib and netpbm. Especially the latter

-makes the whole setup a bit bulky. But that's unavoidable given the many

-features of pnmtopng.

-

-

-What now

---------

-At this moment libpng is in a very stable state and can do much of the

-work done in pnmtopng. Also, pnmtopng needs to be upgraded to the new

-interface of libpng. Hence, it is time for a rewrite from the ground up

-of pnmtopng and pngtopnm. This will happen in the near future (stay

-tuned). The new package will get a different name to distinguish it from

-the old one: PngPlus.

-

-To experiment a bit with the new interface of libpng, I started off with

-a small prototype that contains only the basic functionality. It doesn't

-have any of the options to read or write special chunks and it will do

-no gamma correction. But this makes it also a simple program that is

-quite easy to understand and can serve well as a template for other

-software developments. (By now there are of course a couple of programs,

-like Greg Roelofs' rpng/wpng, that can be used just as good.)

-

-

-Can and can not

----------------

-As this is the small brother of the future PngPlus, I called this fellow

-PngMinus. Because I started this development in good-old Turbo-C, I

-avoided the use the netpbm library, which requires DOS extenders. Again,

-another reason to call it PngMinus (minus netpbm :-). So, part of the

-program are some elementary routines to read / write pgm- and ppm-files.

-It does not read b&w pbm-files.

-

-The downside of this approach is that you can not use them on images

-that require blocks of memory bigger than 64k (the DOS version). For

-larger images you will get an out-of-memory error.

-

-As said before, PngMinus doesn't correct for gamma. When reading

-png-files you can do this just as well by piping the output of png2pnm

-to pnmgamma, one of the standard PbmPlus tools. This same scenario will

-most probably also be followed in the full-blown future PngPlus, with

-the addition of course of the possibility to create gamma-chunks when

-writing png-files.

-

-On the other hand it supports alpha-channels. When reading a png-image

-you can write the alpha-channel into a pgm-file. And when creating an

-RGB+A png-image, you just combine a ppm-file with a corresponding

-pgm-file containing the alpha-channel. When reading, transparency chunks

-are converted into an alpha-channel and from there on treated the same

-way.

-

-Finally you can opt for writing ascii or binary pgm- and ppm-files. When

-the bit-depth is 16, the format will always be ascii.

-

-

-Using it

---------

-To distinguish them from pnmtopng and PngPlus, the utilities are named

-png2pnm and pnm2png (2 instead of to). The input- and output-files can

-be given as parameters or through redirection. Therefore the programs

-can be part of a pipe.

-

-To list the options type "png2pnm -h" or "pnm2png -h".

-

-

-Just like Scandinavian furniture

---------------------------------

-You have to put it together yourself. I did test the software under

-MS-DOS with Turbo-C 3.0 and under RedHat Linux 4.2 with gcc. In both

-cases I used libpng-1.0.4 and zlib-1.1.3. Later versions should be OK,

-however some older libpng versions have a bug in pngmem.c when using

-Turbo-C 3.0 (see below).

-

-You can build it using one of the two makefiles (make -f makefile.###)

-or use the batch/script files pngminus.bat / pngminus.sh. This assumes

-that you have built the libraries in ../libpng and ../zlib. Using Linux,

-make sure that you have built libpng with makefile.std and not

-makefile.linux (also called .lnx in earlier versions of libpng). The

-latter creates a .so shared-library, while the PngMinus makefile assumes

-a normal .a static library.

-

-If you create a ../pngsuite directory and then store the basn####.png

-files from PngSuite (http://www.schaik.com/pngsuite/) in there, you can

-test in one go the proper functioning of PngMinus, see png2pnm.bat and

-pnm2png.bat (or the .sh versions).

-

-

-Warranty

--------

-Please, remember that this was just a small experiment to learn a few

-things. It will have many unforeseen features <vbg>. Who said bugs? Use

-it when you are in need for something simple or when you want to start

-developing your own stuff.

-

-

-The Turbo bug

--------------

-** pngmem.old

-          hptr = (png_byte huge *)((long)(hptr) & 0xfffffff0L);

-          hptr += 16L;

-** pngmem.c

-          hptr = (png_byte huge *)((long)(hptr) & 0xfffffff0L);

-          hptr = hptr + 16L;

-**

-

-** pngmem.old

-          png_ptr->offset_table_ptr[i] = (png_bytep)hptr;

-          hptr += (png_uint_32)65536L;

-** pngmem.c

-          png_ptr->offset_table_ptr[i] = (png_bytep)hptr;

-          hptr = hptr + 65536L;

-**

-

-

-The end

--------

-Willem van Schaik

-mailto:willem@schaik.com

-http://www.schaik.com/png/

--------

-Oct 1999

-

+PngMinus
+--------
+(copyright Willem van Schaik, 1999)
+
+
+License
+-------
+
+Permission to use, copy, modify, and distribute this software and
+its documentation for any purpose and without fee is hereby granted,
+provided that the above copyright notice appear in all copies and
+that both that copyright notice and this permission notice appear in
+supporting documentation. This software is provided "as is" without
+express or implied warranty.
+
+
+Some history
+------------
+Soon after the creation of PNG in 1995, the need was felt for a set of
+pnmtopng / pngtopnm utilities. Independantly Alexander Lehmann and I
+(Willem van Schaik) started such a project. Luckily we discovered this
+and merged the two together into pnmtopng.tar.gz, which is available
+from a/o ftp://ftp.simplesystems.org/pub/libpng/png/.
+
+These two utilities have many, many options and make use of most of the
+features of PNG, like gamma, alpha, sbit, text-chunks, etc. This makes
+the utilities quite complex and by now not anymore very maintainable.
+When we wrote these programs, libpng was still in an early stage.
+Therefore, lots of the functionality that we put in our software can now
+be done using transform-functions in libpng.
+
+Finally, to compile these programs, you need to have installed and
+compiled three libraries: libpng, zlib and netpbm. Especially the latter
+makes the whole setup a bit bulky. But that's unavoidable given the many
+features of pnmtopng.
+
+
+What now
+--------
+At this moment libpng is in a very stable state and can do much of the
+work done in pnmtopng. Also, pnmtopng needs to be upgraded to the new
+interface of libpng. Hence, it is time for a rewrite from the ground up
+of pnmtopng and pngtopnm. This will happen in the near future (stay
+tuned). The new package will get a different name to distinguish it from
+the old one: PngPlus.
+
+To experiment a bit with the new interface of libpng, I started off with
+a small prototype that contains only the basic functionality. It doesn't
+have any of the options to read or write special chunks and it will do
+no gamma correction. But this makes it also a simple program that is
+quite easy to understand and can serve well as a template for other
+software developments. (By now there are of course a couple of programs,
+like Greg Roelofs' rpng/wpng, that can be used just as good.)
+
+
+Can and can not
+---------------
+As this is the small brother of the future PngPlus, I called this fellow
+PngMinus. Because I started this development in good-old Turbo-C, I
+avoided the use the netpbm library, which requires DOS extenders. Again,
+another reason to call it PngMinus (minus netpbm :-). So, part of the
+program are some elementary routines to read / write pgm- and ppm-files.
+It does not read b&w pbm-files.
+
+The downside of this approach is that you can not use them on images
+that require blocks of memory bigger than 64k (the DOS version). For
+larger images you will get an out-of-memory error.
+
+As said before, PngMinus doesn't correct for gamma. When reading
+png-files you can do this just as well by piping the output of png2pnm
+to pnmgamma, one of the standard PbmPlus tools. This same scenario will
+most probably also be followed in the full-blown future PngPlus, with
+the addition of course of the possibility to create gamma-chunks when
+writing png-files.
+
+On the other hand it supports alpha-channels. When reading a png-image
+you can write the alpha-channel into a pgm-file. And when creating an
+RGB+A png-image, you just combine a ppm-file with a corresponding
+pgm-file containing the alpha-channel. When reading, transparency chunks
+are converted into an alpha-channel and from there on treated the same
+way.
+
+Finally you can opt for writing ascii or binary pgm- and ppm-files. When
+the bit-depth is 16, the format will always be ascii.
+
+
+Using it
+--------
+To distinguish them from pnmtopng and PngPlus, the utilities are named
+png2pnm and pnm2png (2 instead of to). The input- and output-files can
+be given as parameters or through redirection. Therefore the programs
+can be part of a pipe.
+
+To list the options type "png2pnm -h" or "pnm2png -h".
+
+
+Just like Scandinavian furniture
+--------------------------------
+You have to put it together yourself. I did test the software under
+MS-DOS with Turbo-C 3.0 and under RedHat Linux 4.2 with gcc. In both
+cases I used libpng-1.0.4 and zlib-1.1.3. Later versions should be OK,
+however some older libpng versions have a bug in pngmem.c when using
+Turbo-C 3.0 (see below).
+
+You can build it using one of the two makefiles (make -f makefile.###)
+or use the batch/script files pngminus.bat / pngminus.sh. This assumes
+that you have built the libraries in ../libpng and ../zlib. Using Linux,
+make sure that you have built libpng with makefile.std and not
+makefile.linux (also called .lnx in earlier versions of libpng). The
+latter creates a .so shared-library, while the PngMinus makefile assumes
+a normal .a static library.
+
+If you create a ../pngsuite directory and then store the basn####.png
+files from PngSuite (http://www.schaik.com/pngsuite/) in there, you can
+test in one go the proper functioning of PngMinus, see png2pnm.bat and
+pnm2png.bat (or the .sh versions).
+
+
+Warranty
+-------
+Please, remember that this was just a small experiment to learn a few
+things. It will have many unforeseen features <vbg>. Who said bugs? Use
+it when you are in need for something simple or when you want to start
+developing your own stuff.
+
+
+The Turbo bug
+-------------
+** pngmem.old
+          hptr = (png_byte huge *)((long)(hptr) & 0xfffffff0L);
+          hptr += 16L;
+** pngmem.c
+          hptr = (png_byte huge *)((long)(hptr) & 0xfffffff0L);
+          hptr = hptr + 16L;
+**
+
+** pngmem.old
+          png_ptr->offset_table_ptr[i] = (png_bytep)hptr;
+          hptr += (png_uint_32)65536L;
+** pngmem.c
+          png_ptr->offset_table_ptr[i] = (png_bytep)hptr;
+          hptr = hptr + 65536L;
+**
+
+
+The end
+-------
+Willem van Schaik
+mailto:willem@schaik.com
+http://www.schaik.com/png/
+-------
+Oct 1999
+
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/makefile.std b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/makefile.std
index a121032..fa7b590 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/makefile.std
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/makefile.std
@@ -1,65 +1,65 @@
-# Makefile for PngMinus (png2pnm and pnm2png)

-# Linux / Unix

-

-#CC=cc

-CC=gcc

-LD=$(CC)

-

-RM=rm -f

-

-#PNGPATH = /usr/local

-#PNGINC = -I$(PNGPATH)/include/libpng15

-#PNGLIB = -L$(PNGPATH)/lib -lpng15

-#PNGLIBS = $(PNGPATH)/lib/libpng15.a

-PNGINC = -I../..

-PNGLIB = -L../.. -lpng

-PNGLIBS = ../../libpng.a

-

-#ZPATH = /usr/local

-#ZINC = -I$(ZPATH)/include

-#ZLIB = -L$(ZPATH)/lib -lz

-#ZLIBS = $(ZPATH)/lib/libz.a

-ZINC = -I../../../zlib

-ZLIB = -L../../../zlib -lz

-ZLIBS = ../../../zlib/libz.a

-

-CFLAGS=$(PNGINC) $(ZINC)

-LDLIBS=$(PNGLIB) $(ZLIB)

-LDLIBSS=$(PNGLIBS) $(ZLIBS)

-C=.c

-O=.o

-L=.a

-E=

-

-# dependencies

-

-#all: png2pnm$(E) pnm2png$(E)

-all: png2pnm$(E) pnm2png$(E) png2pnm-static$(E) pnm2png-static$(E)

-

-png2pnm$(O): png2pnm$(C)

-        $(CC) -c $(CFLAGS) png2pnm$(C)

-

-png2pnm$(E): png2pnm$(O)

-        $(LD) $(LDFLAGS) -o png2pnm$(E) png2pnm$(O) $(LDLIBS) -lm

-

-png2pnm-static$(E): png2pnm$(O)

-        $(LD) $(LDFLAGS) -o png2pnm-static$(E) png2pnm$(O) $(LDLIBSS) -lm

-

-pnm2png$(O): pnm2png$(C)

-        $(CC) -c $(CFLAGS) pnm2png$(C)

-

-pnm2png$(E): pnm2png$(O)

-        $(LD) $(LDFLAGS) -o pnm2png$(E) pnm2png$(O) $(LDLIBS) -lm

-

-pnm2png-static$(E): pnm2png$(O)

-        $(LD) $(LDFLAGS) -o pnm2png-static$(E) pnm2png$(O) $(LDLIBSS) -lm

-

-clean:

-        $(RM) png2pnm$(O)

-        $(RM) pnm2png$(O)

-        $(RM) png2pnm$(E)

-        $(RM) pnm2png$(E)

-        $(RM) png2pnm-static$(E)

-        $(RM) pnm2png-static$(E)

-

-# End of makefile for png2pnm / pnm2png

+# Makefile for PngMinus (png2pnm and pnm2png)
+# Linux / Unix
+
+#CC=cc
+CC=gcc
+LD=$(CC)
+
+RM=rm -f
+
+#PNGPATH = /usr/local
+#PNGINC = -I$(PNGPATH)/include/libpng15
+#PNGLIB = -L$(PNGPATH)/lib -lpng15
+#PNGLIBS = $(PNGPATH)/lib/libpng15.a
+PNGINC = -I../..
+PNGLIB = -L../.. -lpng
+PNGLIBS = ../../libpng.a
+
+#ZPATH = /usr/local
+#ZINC = -I$(ZPATH)/include
+#ZLIB = -L$(ZPATH)/lib -lz
+#ZLIBS = $(ZPATH)/lib/libz.a
+ZINC = -I../../../zlib
+ZLIB = -L../../../zlib -lz
+ZLIBS = ../../../zlib/libz.a
+
+CFLAGS=$(PNGINC) $(ZINC)
+LDLIBS=$(PNGLIB) $(ZLIB)
+LDLIBSS=$(PNGLIBS) $(ZLIBS)
+C=.c
+O=.o
+L=.a
+E=
+
+# dependencies
+
+#all: png2pnm$(E) pnm2png$(E)
+all: png2pnm$(E) pnm2png$(E) png2pnm-static$(E) pnm2png-static$(E)
+
+png2pnm$(O): png2pnm$(C)
+        $(CC) -c $(CFLAGS) png2pnm$(C)
+
+png2pnm$(E): png2pnm$(O)
+        $(LD) $(LDFLAGS) -o png2pnm$(E) png2pnm$(O) $(LDLIBS) -lm
+
+png2pnm-static$(E): png2pnm$(O)
+        $(LD) $(LDFLAGS) -o png2pnm-static$(E) png2pnm$(O) $(LDLIBSS) -lm
+
+pnm2png$(O): pnm2png$(C)
+        $(CC) -c $(CFLAGS) pnm2png$(C)
+
+pnm2png$(E): pnm2png$(O)
+        $(LD) $(LDFLAGS) -o pnm2png$(E) pnm2png$(O) $(LDLIBS) -lm
+
+pnm2png-static$(E): pnm2png$(O)
+        $(LD) $(LDFLAGS) -o pnm2png-static$(E) pnm2png$(O) $(LDLIBSS) -lm
+
+clean:
+        $(RM) png2pnm$(O)
+        $(RM) pnm2png$(O)
+        $(RM) png2pnm$(E)
+        $(RM) pnm2png$(E)
+        $(RM) png2pnm-static$(E)
+        $(RM) pnm2png-static$(E)
+
+# End of makefile for png2pnm / pnm2png
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/makefile.tc3 b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/makefile.tc3
index 01062cc..404f18d 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/makefile.tc3
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/makefile.tc3
@@ -1,38 +1,38 @@
-# Makefile for PngMinus (png2pnm and pnm2png)

-# TurboC++ 3.0

-

-CC=tcc -Ic:\tc3\inc

-LD=tcc -Lc:\tc3\lib

-LB=tlib

-RM=del

-CP=copy

-MODEL=l

-CCFLAGS=-O -m$(MODEL) -I..\libpng -I..\zlib

-LDFLAGS=-m$(MODEL) -L..\libpng -L..\zlib

-C=.c

-O=.obj

-L=.lib

-E=.exe

-

-# dependencies

-

-all: png2pnm$(E) pnm2png$(E)

-

-png2pnm$(O): png2pnm$(C)

-        $(CC) -c $(CCFLAGS) png2pnm$(C)

-

-png2pnm$(E): png2pnm$(O)

-        $(LD) $(LDFLAGS) png2pnm$(O) libpng$(L) zlib$(L)

-

-pnm2png$(O): pnm2png$(C)

-        $(CC) -c $(CCFLAGS) pnm2png$(C)

-

-pnm2png$(E): pnm2png$(O)

-        $(LD) $(LDFLAGS) pnm2png$(O) libpng$(L) zlib$(L)

-

-clean:

-        $(RM) *$(O)

-        $(RM) *$(E)

-

-# End of makefile for png2pnm / pnm2png

-

+# Makefile for PngMinus (png2pnm and pnm2png)
+# TurboC++ 3.0
+
+CC=tcc -Ic:\tc3\inc
+LD=tcc -Lc:\tc3\lib
+LB=tlib
+RM=del
+CP=copy
+MODEL=l
+CCFLAGS=-O -m$(MODEL) -I..\libpng -I..\zlib
+LDFLAGS=-m$(MODEL) -L..\libpng -L..\zlib
+C=.c
+O=.obj
+L=.lib
+E=.exe
+
+# dependencies
+
+all: png2pnm$(E) pnm2png$(E)
+
+png2pnm$(O): png2pnm$(C)
+        $(CC) -c $(CCFLAGS) png2pnm$(C)
+
+png2pnm$(E): png2pnm$(O)
+        $(LD) $(LDFLAGS) png2pnm$(O) libpng$(L) zlib$(L)
+
+pnm2png$(O): pnm2png$(C)
+        $(CC) -c $(CCFLAGS) pnm2png$(C)
+
+pnm2png$(E): pnm2png$(O)
+        $(LD) $(LDFLAGS) pnm2png$(O) libpng$(L) zlib$(L)
+
+clean:
+        $(RM) *$(O)
+        $(RM) *$(E)
+
+# End of makefile for png2pnm / pnm2png
+
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/makevms.com b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/makevms.com
index 96c3147..00561bc 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/makevms.com
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/makevms.com
@@ -1,92 +1,92 @@
-$!------------------------------------------------------------------------------

-$! make Contrib programs of libpng under OpenVMS

-$!

-$!

-$! Look for the compiler used

-$!

-$ zlibsrc = "[---.zlib]"

-$ ccopt="/include=(''zlibsrc',[--])"

-$ if f$getsyi("HW_MODEL").ge.1024

-$ then

-$  ccopt = "/prefix=all"+ccopt

-$  comp  = "__decc__=1"

-$  if f$trnlnm("SYS").eqs."" then define sys sys$library:

-$ else

-$  if f$search("SYS$SYSTEM:DECC$COMPILER.EXE").eqs.""

-$   then

-$    if f$trnlnm("SYS").eqs."" then define sys sys$library:

-$    if f$search("SYS$SYSTEM:VAXC.EXE").eqs.""

-$     then

-$      comp  = "__gcc__=1"

-$      CC :== GCC

-$     else

-$      comp = "__vaxc__=1"

-$     endif

-$   else

-$    if f$trnlnm("SYS").eqs."" then define sys decc$library_include:

-$    ccopt = "/decc/prefix=all"+ccopt

-$    comp  = "__decc__=1"

-$  endif

-$ endif

-$ open/write lopt lib.opt

-$ write lopt "[--]libpng.olb/lib"

-$ write lopt "''zlibsrc'libz.olb/lib"

-$ close lopt

-$ open/write xopt x11.opt

-$ write xopt "sys$library:decw$xlibshr.exe/share"

-$ close xopt

-$ write sys$output "Compiling PNG contrib programs ..."

-$   write sys$output "Building pnm2png..."

-$   CALL MAKE pnm2png.OBJ "cc ''CCOPT' pnm2png" -

-        pnm2png.c

-$   call make pnm2png.exe -

-        "LINK pnm2png,lib.opt/opt" -

-        pnm2png.obj

-$   write sys$output "Building png2pnm..."

-$   CALL MAKE png2pnm.OBJ "cc ''CCOPT' png2pnm" -

-        png2pnm.c

-$   call make png2pnm.exe -

-        "LINK png2pnm,lib.opt/opt" -

-        png2pnm.obj

-$ exit

-$!

-$!

-$MAKE: SUBROUTINE   !SUBROUTINE TO CHECK DEPENDENCIES

-$ V = 'F$Verify(0)

-$! P1 = What we are trying to make

-$! P2 = Command to make it

-$! P3 - P8  What it depends on

-$

-$ If F$Search(P1) .Eqs. "" Then Goto Makeit

-$ Time = F$CvTime(F$File(P1,"RDT"))

-$arg=3

-$Loop:

-$       Argument = P'arg

-$       If Argument .Eqs. "" Then Goto Exit

-$       El=0

-$Loop2:

-$       File = F$Element(El," ",Argument)

-$       If File .Eqs. " " Then Goto Endl

-$       AFile = ""

-$Loop3:

-$       OFile = AFile

-$       AFile = F$Search(File)

-$       If AFile .Eqs. "" .Or. AFile .Eqs. OFile Then Goto NextEl

-$       If F$CvTime(F$File(AFile,"RDT")) .Ges. Time Then Goto Makeit

-$       Goto Loop3

-$NextEL:

-$       El = El + 1

-$       Goto Loop2

-$EndL:

-$ arg=arg+1

-$ If arg .Le. 8 Then Goto Loop

-$ Goto Exit

-$

-$Makeit:

-$ VV=F$VERIFY(0)

-$ write sys$output P2

-$ 'P2

-$ VV='F$Verify(VV)

-$Exit:

-$ If V Then Set Verify

-$ENDSUBROUTINE

+$!------------------------------------------------------------------------------
+$! make Contrib programs of libpng under OpenVMS
+$!
+$!
+$! Look for the compiler used
+$!
+$ zlibsrc = "[---.zlib]"
+$ ccopt="/include=(''zlibsrc',[--])"
+$ if f$getsyi("HW_MODEL").ge.1024
+$ then
+$  ccopt = "/prefix=all"+ccopt
+$  comp  = "__decc__=1"
+$  if f$trnlnm("SYS").eqs."" then define sys sys$library:
+$ else
+$  if f$search("SYS$SYSTEM:DECC$COMPILER.EXE").eqs.""
+$   then
+$    if f$trnlnm("SYS").eqs."" then define sys sys$library:
+$    if f$search("SYS$SYSTEM:VAXC.EXE").eqs.""
+$     then
+$      comp  = "__gcc__=1"
+$      CC :== GCC
+$     else
+$      comp = "__vaxc__=1"
+$     endif
+$   else
+$    if f$trnlnm("SYS").eqs."" then define sys decc$library_include:
+$    ccopt = "/decc/prefix=all"+ccopt
+$    comp  = "__decc__=1"
+$  endif
+$ endif
+$ open/write lopt lib.opt
+$ write lopt "[--]libpng.olb/lib"
+$ write lopt "''zlibsrc'libz.olb/lib"
+$ close lopt
+$ open/write xopt x11.opt
+$ write xopt "sys$library:decw$xlibshr.exe/share"
+$ close xopt
+$ write sys$output "Compiling PNG contrib programs ..."
+$   write sys$output "Building pnm2png..."
+$   CALL MAKE pnm2png.OBJ "cc ''CCOPT' pnm2png" -
+        pnm2png.c
+$   call make pnm2png.exe -
+        "LINK pnm2png,lib.opt/opt" -
+        pnm2png.obj
+$   write sys$output "Building png2pnm..."
+$   CALL MAKE png2pnm.OBJ "cc ''CCOPT' png2pnm" -
+        png2pnm.c
+$   call make png2pnm.exe -
+        "LINK png2pnm,lib.opt/opt" -
+        png2pnm.obj
+$ exit
+$!
+$!
+$MAKE: SUBROUTINE   !SUBROUTINE TO CHECK DEPENDENCIES
+$ V = 'F$Verify(0)
+$! P1 = What we are trying to make
+$! P2 = Command to make it
+$! P3 - P8  What it depends on
+$
+$ If F$Search(P1) .Eqs. "" Then Goto Makeit
+$ Time = F$CvTime(F$File(P1,"RDT"))
+$arg=3
+$Loop:
+$       Argument = P'arg
+$       If Argument .Eqs. "" Then Goto Exit
+$       El=0
+$Loop2:
+$       File = F$Element(El," ",Argument)
+$       If File .Eqs. " " Then Goto Endl
+$       AFile = ""
+$Loop3:
+$       OFile = AFile
+$       AFile = F$Search(File)
+$       If AFile .Eqs. "" .Or. AFile .Eqs. OFile Then Goto NextEl
+$       If F$CvTime(F$File(AFile,"RDT")) .Ges. Time Then Goto Makeit
+$       Goto Loop3
+$NextEL:
+$       El = El + 1
+$       Goto Loop2
+$EndL:
+$ arg=arg+1
+$ If arg .Le. 8 Then Goto Loop
+$ Goto Exit
+$
+$Makeit:
+$ VV=F$VERIFY(0)
+$ write sys$output P2
+$ 'P2
+$ VV='F$Verify(VV)
+$Exit:
+$ If V Then Set Verify
+$ENDSUBROUTINE
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/png2pnm.bat b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/png2pnm.bat
index 85abe3c..449cf36 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/png2pnm.bat
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/png2pnm.bat
@@ -1,41 +1,41 @@
-REM -- grayscale

-png2pnm.exe -noraw ..\pngsuite\basn0g01.png basn0g01.pgm

-png2pnm.exe -noraw ..\pngsuite\basn0g02.png basn0g02.pgm

-png2pnm.exe -noraw ..\pngsuite\basn0g04.png basn0g04.pgm

-png2pnm.exe -noraw ..\pngsuite\basn0g08.png basn0g08.pgm

-png2pnm.exe -noraw ..\pngsuite\basn0g16.png basn0g16.pgm

-REM -- full-color

-png2pnm.exe -noraw ..\pngsuite\basn2c08.png basn2c08.ppm

-png2pnm.exe -noraw ..\pngsuite\basn2c16.png basn2c16.ppm

-REM -- palletted

-png2pnm.exe -noraw ..\pngsuite\basn3p01.png basn3p01.ppm

-png2pnm.exe -noraw ..\pngsuite\basn3p02.png basn3p02.ppm

-png2pnm.exe -noraw ..\pngsuite\basn3p04.png basn3p04.ppm

-png2pnm.exe -noraw ..\pngsuite\basn3p08.png basn3p08.ppm

-REM -- gray with alpha-channel

-png2pnm.exe -noraw ..\pngsuite\basn4a08.png basn4a08.pgm

-png2pnm.exe -noraw ..\pngsuite\basn4a16.png basn4a16.pgm

-REM -- color with alpha-channel

-png2pnm.exe -noraw -alpha basn6a08.pgm ..\pngsuite\basn6a08.png basn6a08.ppm

-png2pnm.exe -noraw -alpha basn6a16.pgm ..\pngsuite\basn6a16.png basn6a16.ppm

-REM -- grayscale

-png2pnm.exe -raw ..\pngsuite\basn0g01.png rawn0g01.pgm

-png2pnm.exe -raw ..\pngsuite\basn0g02.png rawn0g02.pgm

-png2pnm.exe -raw ..\pngsuite\basn0g04.png rawn0g04.pgm

-png2pnm.exe -raw ..\pngsuite\basn0g08.png rawn0g08.pgm

-png2pnm.exe -raw ..\pngsuite\basn0g16.png rawn0g16.pgm

-REM -- full-color

-png2pnm.exe -raw ..\pngsuite\basn2c08.png rawn2c08.ppm

-png2pnm.exe -raw ..\pngsuite\basn2c16.png rawn2c16.ppm

-REM -- palletted

-png2pnm.exe -raw ..\pngsuite\basn3p01.png rawn3p01.ppm

-png2pnm.exe -raw ..\pngsuite\basn3p02.png rawn3p02.ppm

-png2pnm.exe -raw ..\pngsuite\basn3p04.png rawn3p04.ppm

-png2pnm.exe -raw ..\pngsuite\basn3p08.png rawn3p08.ppm

-REM -- gray with alpha-channel

-png2pnm.exe -raw ..\pngsuite\basn4a08.png rawn4a08.pgm

-png2pnm.exe -raw ..\pngsuite\basn4a16.png rawn4a16.pgm

-REM -- color with alpha-channel

-png2pnm.exe -noraw -alpha rawn6a08.pgm ..\pngsuite\basn6a08.png rawn6a08.ppm

-png2pnm.exe -noraw -alpha rawn6a16.pgm ..\pngsuite\basn6a16.png rawn6a16.ppm

-

+REM -- grayscale
+png2pnm.exe -noraw ..\pngsuite\basn0g01.png basn0g01.pgm
+png2pnm.exe -noraw ..\pngsuite\basn0g02.png basn0g02.pgm
+png2pnm.exe -noraw ..\pngsuite\basn0g04.png basn0g04.pgm
+png2pnm.exe -noraw ..\pngsuite\basn0g08.png basn0g08.pgm
+png2pnm.exe -noraw ..\pngsuite\basn0g16.png basn0g16.pgm
+REM -- full-color
+png2pnm.exe -noraw ..\pngsuite\basn2c08.png basn2c08.ppm
+png2pnm.exe -noraw ..\pngsuite\basn2c16.png basn2c16.ppm
+REM -- palletted
+png2pnm.exe -noraw ..\pngsuite\basn3p01.png basn3p01.ppm
+png2pnm.exe -noraw ..\pngsuite\basn3p02.png basn3p02.ppm
+png2pnm.exe -noraw ..\pngsuite\basn3p04.png basn3p04.ppm
+png2pnm.exe -noraw ..\pngsuite\basn3p08.png basn3p08.ppm
+REM -- gray with alpha-channel
+png2pnm.exe -noraw ..\pngsuite\basn4a08.png basn4a08.pgm
+png2pnm.exe -noraw ..\pngsuite\basn4a16.png basn4a16.pgm
+REM -- color with alpha-channel
+png2pnm.exe -noraw -alpha basn6a08.pgm ..\pngsuite\basn6a08.png basn6a08.ppm
+png2pnm.exe -noraw -alpha basn6a16.pgm ..\pngsuite\basn6a16.png basn6a16.ppm
+REM -- grayscale
+png2pnm.exe -raw ..\pngsuite\basn0g01.png rawn0g01.pgm
+png2pnm.exe -raw ..\pngsuite\basn0g02.png rawn0g02.pgm
+png2pnm.exe -raw ..\pngsuite\basn0g04.png rawn0g04.pgm
+png2pnm.exe -raw ..\pngsuite\basn0g08.png rawn0g08.pgm
+png2pnm.exe -raw ..\pngsuite\basn0g16.png rawn0g16.pgm
+REM -- full-color
+png2pnm.exe -raw ..\pngsuite\basn2c08.png rawn2c08.ppm
+png2pnm.exe -raw ..\pngsuite\basn2c16.png rawn2c16.ppm
+REM -- palletted
+png2pnm.exe -raw ..\pngsuite\basn3p01.png rawn3p01.ppm
+png2pnm.exe -raw ..\pngsuite\basn3p02.png rawn3p02.ppm
+png2pnm.exe -raw ..\pngsuite\basn3p04.png rawn3p04.ppm
+png2pnm.exe -raw ..\pngsuite\basn3p08.png rawn3p08.ppm
+REM -- gray with alpha-channel
+png2pnm.exe -raw ..\pngsuite\basn4a08.png rawn4a08.pgm
+png2pnm.exe -raw ..\pngsuite\basn4a16.png rawn4a16.pgm
+REM -- color with alpha-channel
+png2pnm.exe -noraw -alpha rawn6a08.pgm ..\pngsuite\basn6a08.png rawn6a08.ppm
+png2pnm.exe -noraw -alpha rawn6a16.pgm ..\pngsuite\basn6a16.png rawn6a16.ppm
+
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/png2pnm.c b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/png2pnm.c
index ef28d90..2281429 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/png2pnm.c
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/png2pnm.c
@@ -1,430 +1,430 @@
-/*

- *  png2pnm.c --- conversion from PNG-file to PGM/PPM-file

- *  copyright (C) 1999 by Willem van Schaik <willem@schaik.com>

- *

- *  version 1.0 - 1999.10.15 - First version.

- *

- *  Permission to use, copy, modify, and distribute this software and

- *  its documentation for any purpose and without fee is hereby granted,

- *  provided that the above copyright notice appear in all copies and

- *  that both that copyright notice and this permission notice appear in

- *  supporting documentation. This software is provided "as is" without

- *  express or implied warranty.

- */

-

-#include <stdio.h>

-#include <stdlib.h>

-#ifdef __TURBOC__

-#include <mem.h>

-#include <fcntl.h>

-#endif

-

-#ifndef BOOL

-#define BOOL unsigned char

-#endif

-#ifndef TRUE

-#define TRUE (BOOL) 1

-#endif

-#ifndef FALSE

-#define FALSE (BOOL) 0

-#endif

-

-#ifdef __TURBOC__

-#define STDIN  0

-#define STDOUT 1

-#define STDERR 2

-#endif

-

-/* to make png2pnm verbose so we can find problems (needs to be before png.h) */

-#ifndef PNG_DEBUG

-#define PNG_DEBUG 0

-#endif

-

-#include "png.h"

-

-/* Define png_jmpbuf() in case we are using a pre-1.0.6 version of libpng */

-#ifndef png_jmpbuf

-#  define png_jmpbuf(png_ptr) ((png_ptr)->jmpbuf)

-#endif

-

-/* function prototypes */

-

-int  main (int argc, char *argv[]);

-void usage ();

-BOOL png2pnm (FILE *png_file, FILE *pnm_file, FILE *alpha_file, BOOL raw, BOOL alpha);

-

-/*

- *  main

- */

-

-int main(int argc, char *argv[])

-{

-  FILE *fp_rd = stdin;

-  FILE *fp_wr = stdout;

-  FILE *fp_al = NULL;

-  BOOL raw = TRUE;

-  BOOL alpha = FALSE;

-  int argi;

-

-  for (argi = 1; argi < argc; argi++)

-  {

-    if (argv[argi][0] == '-')

-    {

-      switch (argv[argi][1])

-      {

-        case 'n':

-          raw = FALSE;

-          break;

-        case 'r':

-          raw = TRUE;

-          break;

-        case 'a':

-          alpha = TRUE;

-          argi++;

-          if ((fp_al = fopen (argv[argi], "wb")) == NULL)

-          {

-            fprintf (stderr, "PNM2PNG\n");

-            fprintf (stderr, "Error:  can not create alpha-channel file %s\n", argv[argi]);

-            exit (1);

-          }

-          break;

-        case 'h':

-        case '?':

-          usage();

-          exit(0);

-          break;

-        default:

-          fprintf (stderr, "PNG2PNM\n");

-          fprintf (stderr, "Error:  unknown option %s\n", argv[argi]);

-          usage();

-          exit(1);

-          break;

-      } /* end switch */

-    }

-    else if (fp_rd == stdin)

-    {

-      if ((fp_rd = fopen (argv[argi], "rb")) == NULL)

-      {

-             fprintf (stderr, "PNG2PNM\n");

-            fprintf (stderr, "Error:  file %s does not exist\n", argv[argi]);

-            exit (1);

-      }

-    }

-    else if (fp_wr == stdout)

-    {

-      if ((fp_wr = fopen (argv[argi], "wb")) == NULL)

-      {

-        fprintf (stderr, "PNG2PNM\n");

-        fprintf (stderr, "Error:  can not create file %s\n", argv[argi]);

-        exit (1);

-      }

-    }

-    else

-    {

-      fprintf (stderr, "PNG2PNM\n");

-      fprintf (stderr, "Error:  too many parameters\n");

-      usage();

-      exit(1);

-    }

-  } /* end for */

-

-#ifdef __TURBOC__

-  /* set stdin/stdout if required to binary */

-  if (fp_rd == stdin)

-  {

-    setmode (STDIN, O_BINARY);

-  }

-  if ((raw) && (fp_wr == stdout))

-  {

-    setmode (STDOUT, O_BINARY);

-  }

-#endif

-

-  /* call the conversion program itself */

-  if (png2pnm (fp_rd, fp_wr, fp_al, raw, alpha) == FALSE)

-  {

-    fprintf (stderr, "PNG2PNM\n");

-    fprintf (stderr, "Error:  unsuccessful conversion of PNG-image\n");

-    exit(1);

-  }

-

-  /* close input file */

-  fclose (fp_rd);

-  /* close output file */

-  fclose (fp_wr);

-  /* close alpha file */

-  if (alpha)

-    fclose (fp_al);

-

-  return 0;

-}

-

-/*

- *  usage

- */

-

-void usage()

-{

-  fprintf (stderr, "PNG2PNM\n");

-  fprintf (stderr, "   by Willem van Schaik, 1999\n");

-#ifdef __TURBOC__

-  fprintf (stderr, "   for Turbo-C and Borland-C compilers\n");

-#else

-  fprintf (stderr, "   for Linux (and Unix) compilers\n");

-#endif

-  fprintf (stderr, "Usage:  png2pnm [options] <file>.png [<file>.pnm]\n");

-  fprintf (stderr, "   or:  ... | png2pnm [options]\n");

-  fprintf (stderr, "Options:\n");

-  fprintf (stderr, "   -r[aw]   write pnm-file in binary format (P4/P5/P6) (default)\n");

-  fprintf (stderr, "   -n[oraw] write pnm-file in ascii format (P1/P2/P3)\n");

-  fprintf (stderr, "   -a[lpha] <file>.pgm write PNG alpha channel as pgm-file\n");

-  fprintf (stderr, "   -h | -?  print this help-information\n");

-}

-

-/*

- *  png2pnm

- */

-

-BOOL png2pnm (FILE *png_file, FILE *pnm_file, FILE *alpha_file, BOOL raw, BOOL alpha)

-{

-  png_struct    *png_ptr = NULL;

-  png_info        *info_ptr = NULL;

-  png_byte      buf[8];

-  png_byte      *png_pixels = NULL;

-  png_byte      **row_pointers = NULL;

-  png_byte      *pix_ptr = NULL;

-  png_uint_32   row_bytes;

-

-  png_uint_32   width;

-  png_uint_32   height;

-  int           bit_depth;

-  int           channels;

-  int           color_type;

-  int           alpha_present;

-  int           row, col;

-  int           ret;

-  int           i;

-  long          dep_16;

-

-  /* read and check signature in PNG file */

-  ret = fread (buf, 1, 8, png_file);

-  if (ret != 8)

-    return FALSE;

-

-  ret = png_sig_cmp (buf, 0, 8);

-  if (ret)

-    return FALSE;

-

-  /* create png and info structures */

-

-  png_ptr = png_create_read_struct (PNG_LIBPNG_VER_STRING,

-    NULL, NULL, NULL);

-  if (!png_ptr)

-    return FALSE;   /* out of memory */

-

-  info_ptr = png_create_info_struct (png_ptr);

-  if (!info_ptr)

-  {

-    png_destroy_read_struct (&png_ptr, NULL, NULL);

-    return FALSE;   /* out of memory */

-  }

-

-  if (setjmp (png_jmpbuf(png_ptr)))

-  {

-    png_destroy_read_struct (&png_ptr, &info_ptr, NULL);

-    return FALSE;

-  }

-

-  /* set up the input control for C streams */

-  png_init_io (png_ptr, png_file);

-  png_set_sig_bytes (png_ptr, 8);  /* we already read the 8 signature bytes */

-

-  /* read the file information */

-  png_read_info (png_ptr, info_ptr);

-

-  /* get size and bit-depth of the PNG-image */

-  png_get_IHDR (png_ptr, info_ptr,

-    &width, &height, &bit_depth, &color_type,

-    NULL, NULL, NULL);

-

-  /* set-up the transformations */

-

-  /* transform paletted images into full-color rgb */

-  if (color_type == PNG_COLOR_TYPE_PALETTE)

-    png_set_expand (png_ptr);

-  /* expand images to bit-depth 8 (only applicable for grayscale images) */

-  if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)

-    png_set_expand (png_ptr);

-  /* transform transparency maps into full alpha-channel */

-  if (png_get_valid (png_ptr, info_ptr, PNG_INFO_tRNS))

-    png_set_expand (png_ptr);

-

-#ifdef NJET

-  /* downgrade 16-bit images to 8 bit */

-  if (bit_depth == 16)

-    png_set_strip_16 (png_ptr);

-  /* transform grayscale images into full-color */

-  if (color_type == PNG_COLOR_TYPE_GRAY ||

-    color_type == PNG_COLOR_TYPE_GRAY_ALPHA)

-    png_set_gray_to_rgb (png_ptr);

-  /* only if file has a file gamma, we do a correction */

-  if (png_get_gAMA (png_ptr, info_ptr, &file_gamma))

-    png_set_gamma (png_ptr, (double) 2.2, file_gamma);

-#endif

-

-  /* all transformations have been registered; now update info_ptr data,

-   * get rowbytes and channels, and allocate image memory */

-

-  png_read_update_info (png_ptr, info_ptr);

-

-  /* get the new color-type and bit-depth (after expansion/stripping) */

-  png_get_IHDR (png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,

-    NULL, NULL, NULL);

-

-  /* check for 16-bit files */

-  if (bit_depth == 16)

-  {

-    raw = FALSE;

-#ifdef __TURBOC__

-    pnm_file->flags &= ~((unsigned) _F_BIN);

-#endif

-  }

-

-  /* calculate new number of channels and store alpha-presence */

-  if (color_type == PNG_COLOR_TYPE_GRAY)

-    channels = 1;

-  else if (color_type == PNG_COLOR_TYPE_GRAY_ALPHA)

-    channels = 2;

-  else if (color_type == PNG_COLOR_TYPE_RGB)

-    channels = 3;

-  else if (color_type == PNG_COLOR_TYPE_RGB_ALPHA)

-    channels = 4;

-  else

-    channels = 0; /* should never happen */

-  alpha_present = (channels - 1) % 2;

-

-  /* check if alpha is expected to be present in file */

-  if (alpha && !alpha_present)

-  {

-    fprintf (stderr, "PNG2PNM\n");

-    fprintf (stderr, "Error:  PNG-file doesn't contain alpha channel\n");

-    exit (1);

-  }

-

-  /* row_bytes is the width x number of channels x (bit-depth / 8) */

-  row_bytes = png_get_rowbytes (png_ptr, info_ptr);

-

-  if ((png_pixels = (png_byte *) malloc (row_bytes * height * sizeof (png_byte))) == NULL) {

-    png_destroy_read_struct (&png_ptr, &info_ptr, NULL);

-    return FALSE;

-  }

-

-  if ((row_pointers = (png_byte **) malloc (height * sizeof (png_bytep))) == NULL)

-  {

-    png_destroy_read_struct (&png_ptr, &info_ptr, NULL);

-    free (png_pixels);

-    png_pixels = NULL;

-    return FALSE;

-  }

-

-  /* set the individual row_pointers to point at the correct offsets */

-  for (i = 0; i < (height); i++)

-    row_pointers[i] = png_pixels + i * row_bytes;

-

-  /* now we can go ahead and just read the whole image */

-  png_read_image (png_ptr, row_pointers);

-

-  /* read rest of file, and get additional chunks in info_ptr - REQUIRED */

-  png_read_end (png_ptr, info_ptr);

-

-  /* clean up after the read, and free any memory allocated - REQUIRED */

-  png_destroy_read_struct (&png_ptr, &info_ptr, (png_infopp) NULL);

-

-  /* write header of PNM file */

-

-  if ((color_type == PNG_COLOR_TYPE_GRAY) ||

-      (color_type == PNG_COLOR_TYPE_GRAY_ALPHA))

-  {

-    fprintf (pnm_file, "%s\n", (raw) ? "P5" : "P2");

-    fprintf (pnm_file, "%d %d\n", (int) width, (int) height);

-    fprintf (pnm_file, "%ld\n", ((1L << (int) bit_depth) - 1L));

-  }

-  else if ((color_type == PNG_COLOR_TYPE_RGB) ||

-           (color_type == PNG_COLOR_TYPE_RGB_ALPHA))

-  {

-    fprintf (pnm_file, "%s\n", (raw) ? "P6" : "P3");

-    fprintf (pnm_file, "%d %d\n", (int) width, (int) height);

-    fprintf (pnm_file, "%ld\n", ((1L << (int) bit_depth) - 1L));

-  }

-

-  /* write header of PGM file with alpha channel */

-

-  if ((alpha) &&

-      ((color_type == PNG_COLOR_TYPE_GRAY_ALPHA) ||

-       (color_type == PNG_COLOR_TYPE_RGB_ALPHA)))

-  {

-    fprintf (alpha_file, "%s\n", (raw) ? "P5" : "P2");

-    fprintf (alpha_file, "%d %d\n", (int) width, (int) height);

-    fprintf (alpha_file, "%ld\n", ((1L << (int) bit_depth) - 1L));

-  }

-

-  /* write data to PNM file */

-  pix_ptr = png_pixels;

-

-  for (row = 0; row < height; row++)

-  {

-    for (col = 0; col < width; col++)

-    {

-      for (i = 0; i < (channels - alpha_present); i++)

-      {

-        if (raw)

-          fputc ((int) *pix_ptr++ , pnm_file);

-        else

-          if (bit_depth == 16){

-            dep_16 = (long) *pix_ptr++;

-            fprintf (pnm_file, "%ld ", (dep_16 << 8) + ((long) *pix_ptr++));

-          }

-          else

-            fprintf (pnm_file, "%ld ", (long) *pix_ptr++);

-      }

-      if (alpha_present)

-      {

-        if (!alpha)

-        {

-          pix_ptr++; /* alpha */

-          if (bit_depth == 16)

-            pix_ptr++;

-        }

-        else /* output alpha-channel as pgm file */

-        {

-          if (raw)

-            fputc ((int) *pix_ptr++ , alpha_file);

-          else

-            if (bit_depth == 16){

-              dep_16 = (long) *pix_ptr++;

-              fprintf (alpha_file, "%ld ", (dep_16 << 8) + (long) *pix_ptr++);

-            }

-            else

-              fprintf (alpha_file, "%ld ", (long) *pix_ptr++);

-        }

-      } /* if alpha_present */

-

-      if (!raw)

-        if (col % 4 == 3)

-          fprintf (pnm_file, "\n");

-    } /* end for col */

-

-    if (!raw)

-      if (col % 4 != 0)

-        fprintf (pnm_file, "\n");

-  } /* end for row */

-

-  if (row_pointers != (unsigned char**) NULL)

-    free (row_pointers);

-  if (png_pixels != (unsigned char*) NULL)

-    free (png_pixels);

-

-  return TRUE;

-

-} /* end of source */

-

+/*
+ *  png2pnm.c --- conversion from PNG-file to PGM/PPM-file
+ *  copyright (C) 1999 by Willem van Schaik <willem@schaik.com>
+ *
+ *  version 1.0 - 1999.10.15 - First version.
+ *
+ *  Permission to use, copy, modify, and distribute this software and
+ *  its documentation for any purpose and without fee is hereby granted,
+ *  provided that the above copyright notice appear in all copies and
+ *  that both that copyright notice and this permission notice appear in
+ *  supporting documentation. This software is provided "as is" without
+ *  express or implied warranty.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#ifdef __TURBOC__
+#include <mem.h>
+#include <fcntl.h>
+#endif
+
+#ifndef BOOL
+#define BOOL unsigned char
+#endif
+#ifndef TRUE
+#define TRUE (BOOL) 1
+#endif
+#ifndef FALSE
+#define FALSE (BOOL) 0
+#endif
+
+#ifdef __TURBOC__
+#define STDIN  0
+#define STDOUT 1
+#define STDERR 2
+#endif
+
+/* to make png2pnm verbose so we can find problems (needs to be before png.h) */
+#ifndef PNG_DEBUG
+#define PNG_DEBUG 0
+#endif
+
+#include "png.h"
+
+/* Define png_jmpbuf() in case we are using a pre-1.0.6 version of libpng */
+#ifndef png_jmpbuf
+#  define png_jmpbuf(png_ptr) ((png_ptr)->jmpbuf)
+#endif
+
+/* function prototypes */
+
+int  main (int argc, char *argv[]);
+void usage ();
+BOOL png2pnm (FILE *png_file, FILE *pnm_file, FILE *alpha_file, BOOL raw, BOOL alpha);
+
+/*
+ *  main
+ */
+
+int main(int argc, char *argv[])
+{
+  FILE *fp_rd = stdin;
+  FILE *fp_wr = stdout;
+  FILE *fp_al = NULL;
+  BOOL raw = TRUE;
+  BOOL alpha = FALSE;
+  int argi;
+
+  for (argi = 1; argi < argc; argi++)
+  {
+    if (argv[argi][0] == '-')
+    {
+      switch (argv[argi][1])
+      {
+        case 'n':
+          raw = FALSE;
+          break;
+        case 'r':
+          raw = TRUE;
+          break;
+        case 'a':
+          alpha = TRUE;
+          argi++;
+          if ((fp_al = fopen (argv[argi], "wb")) == NULL)
+          {
+            fprintf (stderr, "PNM2PNG\n");
+            fprintf (stderr, "Error:  can not create alpha-channel file %s\n", argv[argi]);
+            exit (1);
+          }
+          break;
+        case 'h':
+        case '?':
+          usage();
+          exit(0);
+          break;
+        default:
+          fprintf (stderr, "PNG2PNM\n");
+          fprintf (stderr, "Error:  unknown option %s\n", argv[argi]);
+          usage();
+          exit(1);
+          break;
+      } /* end switch */
+    }
+    else if (fp_rd == stdin)
+    {
+      if ((fp_rd = fopen (argv[argi], "rb")) == NULL)
+      {
+             fprintf (stderr, "PNG2PNM\n");
+            fprintf (stderr, "Error:  file %s does not exist\n", argv[argi]);
+            exit (1);
+      }
+    }
+    else if (fp_wr == stdout)
+    {
+      if ((fp_wr = fopen (argv[argi], "wb")) == NULL)
+      {
+        fprintf (stderr, "PNG2PNM\n");
+        fprintf (stderr, "Error:  can not create file %s\n", argv[argi]);
+        exit (1);
+      }
+    }
+    else
+    {
+      fprintf (stderr, "PNG2PNM\n");
+      fprintf (stderr, "Error:  too many parameters\n");
+      usage();
+      exit(1);
+    }
+  } /* end for */
+
+#ifdef __TURBOC__
+  /* set stdin/stdout if required to binary */
+  if (fp_rd == stdin)
+  {
+    setmode (STDIN, O_BINARY);
+  }
+  if ((raw) && (fp_wr == stdout))
+  {
+    setmode (STDOUT, O_BINARY);
+  }
+#endif
+
+  /* call the conversion program itself */
+  if (png2pnm (fp_rd, fp_wr, fp_al, raw, alpha) == FALSE)
+  {
+    fprintf (stderr, "PNG2PNM\n");
+    fprintf (stderr, "Error:  unsuccessful conversion of PNG-image\n");
+    exit(1);
+  }
+
+  /* close input file */
+  fclose (fp_rd);
+  /* close output file */
+  fclose (fp_wr);
+  /* close alpha file */
+  if (alpha)
+    fclose (fp_al);
+
+  return 0;
+}
+
+/*
+ *  usage
+ */
+
+void usage()
+{
+  fprintf (stderr, "PNG2PNM\n");
+  fprintf (stderr, "   by Willem van Schaik, 1999\n");
+#ifdef __TURBOC__
+  fprintf (stderr, "   for Turbo-C and Borland-C compilers\n");
+#else
+  fprintf (stderr, "   for Linux (and Unix) compilers\n");
+#endif
+  fprintf (stderr, "Usage:  png2pnm [options] <file>.png [<file>.pnm]\n");
+  fprintf (stderr, "   or:  ... | png2pnm [options]\n");
+  fprintf (stderr, "Options:\n");
+  fprintf (stderr, "   -r[aw]   write pnm-file in binary format (P4/P5/P6) (default)\n");
+  fprintf (stderr, "   -n[oraw] write pnm-file in ascii format (P1/P2/P3)\n");
+  fprintf (stderr, "   -a[lpha] <file>.pgm write PNG alpha channel as pgm-file\n");
+  fprintf (stderr, "   -h | -?  print this help-information\n");
+}
+
+/*
+ *  png2pnm
+ */
+
+BOOL png2pnm (FILE *png_file, FILE *pnm_file, FILE *alpha_file, BOOL raw, BOOL alpha)
+{
+  png_struct    *png_ptr = NULL;
+  png_info        *info_ptr = NULL;
+  png_byte      buf[8];
+  png_byte      *png_pixels = NULL;
+  png_byte      **row_pointers = NULL;
+  png_byte      *pix_ptr = NULL;
+  png_uint_32   row_bytes;
+
+  png_uint_32   width;
+  png_uint_32   height;
+  int           bit_depth;
+  int           channels;
+  int           color_type;
+  int           alpha_present;
+  int           row, col;
+  int           ret;
+  int           i;
+  long          dep_16;
+
+  /* read and check signature in PNG file */
+  ret = fread (buf, 1, 8, png_file);
+  if (ret != 8)
+    return FALSE;
+
+  ret = png_sig_cmp (buf, 0, 8);
+  if (ret)
+    return FALSE;
+
+  /* create png and info structures */
+
+  png_ptr = png_create_read_struct (PNG_LIBPNG_VER_STRING,
+    NULL, NULL, NULL);
+  if (!png_ptr)
+    return FALSE;   /* out of memory */
+
+  info_ptr = png_create_info_struct (png_ptr);
+  if (!info_ptr)
+  {
+    png_destroy_read_struct (&png_ptr, NULL, NULL);
+    return FALSE;   /* out of memory */
+  }
+
+  if (setjmp (png_jmpbuf(png_ptr)))
+  {
+    png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
+    return FALSE;
+  }
+
+  /* set up the input control for C streams */
+  png_init_io (png_ptr, png_file);
+  png_set_sig_bytes (png_ptr, 8);  /* we already read the 8 signature bytes */
+
+  /* read the file information */
+  png_read_info (png_ptr, info_ptr);
+
+  /* get size and bit-depth of the PNG-image */
+  png_get_IHDR (png_ptr, info_ptr,
+    &width, &height, &bit_depth, &color_type,
+    NULL, NULL, NULL);
+
+  /* set-up the transformations */
+
+  /* transform paletted images into full-color rgb */
+  if (color_type == PNG_COLOR_TYPE_PALETTE)
+    png_set_expand (png_ptr);
+  /* expand images to bit-depth 8 (only applicable for grayscale images) */
+  if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
+    png_set_expand (png_ptr);
+  /* transform transparency maps into full alpha-channel */
+  if (png_get_valid (png_ptr, info_ptr, PNG_INFO_tRNS))
+    png_set_expand (png_ptr);
+
+#ifdef NJET
+  /* downgrade 16-bit images to 8 bit */
+  if (bit_depth == 16)
+    png_set_strip_16 (png_ptr);
+  /* transform grayscale images into full-color */
+  if (color_type == PNG_COLOR_TYPE_GRAY ||
+    color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+    png_set_gray_to_rgb (png_ptr);
+  /* only if file has a file gamma, we do a correction */
+  if (png_get_gAMA (png_ptr, info_ptr, &file_gamma))
+    png_set_gamma (png_ptr, (double) 2.2, file_gamma);
+#endif
+
+  /* all transformations have been registered; now update info_ptr data,
+   * get rowbytes and channels, and allocate image memory */
+
+  png_read_update_info (png_ptr, info_ptr);
+
+  /* get the new color-type and bit-depth (after expansion/stripping) */
+  png_get_IHDR (png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
+    NULL, NULL, NULL);
+
+  /* check for 16-bit files */
+  if (bit_depth == 16)
+  {
+    raw = FALSE;
+#ifdef __TURBOC__
+    pnm_file->flags &= ~((unsigned) _F_BIN);
+#endif
+  }
+
+  /* calculate new number of channels and store alpha-presence */
+  if (color_type == PNG_COLOR_TYPE_GRAY)
+    channels = 1;
+  else if (color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+    channels = 2;
+  else if (color_type == PNG_COLOR_TYPE_RGB)
+    channels = 3;
+  else if (color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+    channels = 4;
+  else
+    channels = 0; /* should never happen */
+  alpha_present = (channels - 1) % 2;
+
+  /* check if alpha is expected to be present in file */
+  if (alpha && !alpha_present)
+  {
+    fprintf (stderr, "PNG2PNM\n");
+    fprintf (stderr, "Error:  PNG-file doesn't contain alpha channel\n");
+    exit (1);
+  }
+
+  /* row_bytes is the width x number of channels x (bit-depth / 8) */
+  row_bytes = png_get_rowbytes (png_ptr, info_ptr);
+
+  if ((png_pixels = (png_byte *) malloc (row_bytes * height * sizeof (png_byte))) == NULL) {
+    png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
+    return FALSE;
+  }
+
+  if ((row_pointers = (png_byte **) malloc (height * sizeof (png_bytep))) == NULL)
+  {
+    png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
+    free (png_pixels);
+    png_pixels = NULL;
+    return FALSE;
+  }
+
+  /* set the individual row_pointers to point at the correct offsets */
+  for (i = 0; i < (height); i++)
+    row_pointers[i] = png_pixels + i * row_bytes;
+
+  /* now we can go ahead and just read the whole image */
+  png_read_image (png_ptr, row_pointers);
+
+  /* read rest of file, and get additional chunks in info_ptr - REQUIRED */
+  png_read_end (png_ptr, info_ptr);
+
+  /* clean up after the read, and free any memory allocated - REQUIRED */
+  png_destroy_read_struct (&png_ptr, &info_ptr, (png_infopp) NULL);
+
+  /* write header of PNM file */
+
+  if ((color_type == PNG_COLOR_TYPE_GRAY) ||
+      (color_type == PNG_COLOR_TYPE_GRAY_ALPHA))
+  {
+    fprintf (pnm_file, "%s\n", (raw) ? "P5" : "P2");
+    fprintf (pnm_file, "%d %d\n", (int) width, (int) height);
+    fprintf (pnm_file, "%ld\n", ((1L << (int) bit_depth) - 1L));
+  }
+  else if ((color_type == PNG_COLOR_TYPE_RGB) ||
+           (color_type == PNG_COLOR_TYPE_RGB_ALPHA))
+  {
+    fprintf (pnm_file, "%s\n", (raw) ? "P6" : "P3");
+    fprintf (pnm_file, "%d %d\n", (int) width, (int) height);
+    fprintf (pnm_file, "%ld\n", ((1L << (int) bit_depth) - 1L));
+  }
+
+  /* write header of PGM file with alpha channel */
+
+  if ((alpha) &&
+      ((color_type == PNG_COLOR_TYPE_GRAY_ALPHA) ||
+       (color_type == PNG_COLOR_TYPE_RGB_ALPHA)))
+  {
+    fprintf (alpha_file, "%s\n", (raw) ? "P5" : "P2");
+    fprintf (alpha_file, "%d %d\n", (int) width, (int) height);
+    fprintf (alpha_file, "%ld\n", ((1L << (int) bit_depth) - 1L));
+  }
+
+  /* write data to PNM file */
+  pix_ptr = png_pixels;
+
+  for (row = 0; row < height; row++)
+  {
+    for (col = 0; col < width; col++)
+    {
+      for (i = 0; i < (channels - alpha_present); i++)
+      {
+        if (raw)
+          fputc ((int) *pix_ptr++ , pnm_file);
+        else
+          if (bit_depth == 16){
+            dep_16 = (long) *pix_ptr++;
+            fprintf (pnm_file, "%ld ", (dep_16 << 8) + ((long) *pix_ptr++));
+          }
+          else
+            fprintf (pnm_file, "%ld ", (long) *pix_ptr++);
+      }
+      if (alpha_present)
+      {
+        if (!alpha)
+        {
+          pix_ptr++; /* alpha */
+          if (bit_depth == 16)
+            pix_ptr++;
+        }
+        else /* output alpha-channel as pgm file */
+        {
+          if (raw)
+            fputc ((int) *pix_ptr++ , alpha_file);
+          else
+            if (bit_depth == 16){
+              dep_16 = (long) *pix_ptr++;
+              fprintf (alpha_file, "%ld ", (dep_16 << 8) + (long) *pix_ptr++);
+            }
+            else
+              fprintf (alpha_file, "%ld ", (long) *pix_ptr++);
+        }
+      } /* if alpha_present */
+
+      if (!raw)
+        if (col % 4 == 3)
+          fprintf (pnm_file, "\n");
+    } /* end for col */
+
+    if (!raw)
+      if (col % 4 != 0)
+        fprintf (pnm_file, "\n");
+  } /* end for row */
+
+  if (row_pointers != (unsigned char**) NULL)
+    free (row_pointers);
+  if (png_pixels != (unsigned char*) NULL)
+    free (png_pixels);
+
+  return TRUE;
+
+} /* end of source */
+
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/png2pnm.sh b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/png2pnm.sh
index ee39664..b1c0537 100755
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/png2pnm.sh
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/png2pnm.sh
@@ -1,42 +1,42 @@
-#!/bin/sh

-# -- grayscale

-./png2pnm -noraw ../pngsuite/basn0g01.png basn0g01.pgm

-./png2pnm -noraw ../pngsuite/basn0g02.png basn0g02.pgm

-./png2pnm -noraw ../pngsuite/basn0g04.png basn0g04.pgm

-./png2pnm -noraw ../pngsuite/basn0g08.png basn0g08.pgm

-./png2pnm -noraw ../pngsuite/basn0g16.png basn0g16.pgm

-# -- full-color

-./png2pnm -noraw ../pngsuite/basn2c08.png basn2c08.ppm

-./png2pnm -noraw ../pngsuite/basn2c16.png basn2c16.ppm

-# -- palletted

-./png2pnm -noraw ../pngsuite/basn3p01.png basn3p01.ppm

-./png2pnm -noraw ../pngsuite/basn3p02.png basn3p02.ppm

-./png2pnm -noraw ../pngsuite/basn3p04.png basn3p04.ppm

-./png2pnm -noraw ../pngsuite/basn3p08.png basn3p08.ppm

-# -- gray with alpha-channel

-./png2pnm -noraw ../pngsuite/basn4a08.png basn4a08.pgm

-./png2pnm -noraw ../pngsuite/basn4a16.png basn4a16.pgm

-# -- color with alpha-channel

-./png2pnm -noraw -alpha basn6a08.pgm ../pngsuite/basn6a08.png basn6a08.ppm

-./png2pnm -noraw -alpha basn6a16.pgm ../pngsuite/basn6a16.png basn6a16.ppm

-# -- grayscale

-./png2pnm -raw ../pngsuite/basn0g01.png rawn0g01.pgm

-./png2pnm -raw ../pngsuite/basn0g02.png rawn0g02.pgm

-./png2pnm -raw ../pngsuite/basn0g04.png rawn0g04.pgm

-./png2pnm -raw ../pngsuite/basn0g08.png rawn0g08.pgm

-./png2pnm -raw ../pngsuite/basn0g16.png rawn0g16.pgm

-# -- full-color

-./png2pnm -raw ../pngsuite/basn2c08.png rawn2c08.ppm

-./png2pnm -raw ../pngsuite/basn2c16.png rawn2c16.ppm

-# -- palletted

-./png2pnm -raw ../pngsuite/basn3p01.png rawn3p01.ppm

-./png2pnm -raw ../pngsuite/basn3p02.png rawn3p02.ppm

-./png2pnm -raw ../pngsuite/basn3p04.png rawn3p04.ppm

-./png2pnm -raw ../pngsuite/basn3p08.png rawn3p08.ppm

-# -- gray with alpha-channel

-./png2pnm -raw ../pngsuite/basn4a08.png rawn4a08.pgm

-./png2pnm -raw ../pngsuite/basn4a16.png rawn4a16.pgm

-# -- color with alpha-channel

-./png2pnm -noraw -alpha rawn6a08.pgm ../pngsuite/basn6a08.png rawn6a08.ppm

-./png2pnm -noraw -alpha rawn6a16.pgm ../pngsuite/basn6a16.png rawn6a16.ppm

-

+#!/bin/sh
+# -- grayscale
+./png2pnm -noraw ../pngsuite/basn0g01.png basn0g01.pgm
+./png2pnm -noraw ../pngsuite/basn0g02.png basn0g02.pgm
+./png2pnm -noraw ../pngsuite/basn0g04.png basn0g04.pgm
+./png2pnm -noraw ../pngsuite/basn0g08.png basn0g08.pgm
+./png2pnm -noraw ../pngsuite/basn0g16.png basn0g16.pgm
+# -- full-color
+./png2pnm -noraw ../pngsuite/basn2c08.png basn2c08.ppm
+./png2pnm -noraw ../pngsuite/basn2c16.png basn2c16.ppm
+# -- palletted
+./png2pnm -noraw ../pngsuite/basn3p01.png basn3p01.ppm
+./png2pnm -noraw ../pngsuite/basn3p02.png basn3p02.ppm
+./png2pnm -noraw ../pngsuite/basn3p04.png basn3p04.ppm
+./png2pnm -noraw ../pngsuite/basn3p08.png basn3p08.ppm
+# -- gray with alpha-channel
+./png2pnm -noraw ../pngsuite/basn4a08.png basn4a08.pgm
+./png2pnm -noraw ../pngsuite/basn4a16.png basn4a16.pgm
+# -- color with alpha-channel
+./png2pnm -noraw -alpha basn6a08.pgm ../pngsuite/basn6a08.png basn6a08.ppm
+./png2pnm -noraw -alpha basn6a16.pgm ../pngsuite/basn6a16.png basn6a16.ppm
+# -- grayscale
+./png2pnm -raw ../pngsuite/basn0g01.png rawn0g01.pgm
+./png2pnm -raw ../pngsuite/basn0g02.png rawn0g02.pgm
+./png2pnm -raw ../pngsuite/basn0g04.png rawn0g04.pgm
+./png2pnm -raw ../pngsuite/basn0g08.png rawn0g08.pgm
+./png2pnm -raw ../pngsuite/basn0g16.png rawn0g16.pgm
+# -- full-color
+./png2pnm -raw ../pngsuite/basn2c08.png rawn2c08.ppm
+./png2pnm -raw ../pngsuite/basn2c16.png rawn2c16.ppm
+# -- palletted
+./png2pnm -raw ../pngsuite/basn3p01.png rawn3p01.ppm
+./png2pnm -raw ../pngsuite/basn3p02.png rawn3p02.ppm
+./png2pnm -raw ../pngsuite/basn3p04.png rawn3p04.ppm
+./png2pnm -raw ../pngsuite/basn3p08.png rawn3p08.ppm
+# -- gray with alpha-channel
+./png2pnm -raw ../pngsuite/basn4a08.png rawn4a08.pgm
+./png2pnm -raw ../pngsuite/basn4a16.png rawn4a16.pgm
+# -- color with alpha-channel
+./png2pnm -noraw -alpha rawn6a08.pgm ../pngsuite/basn6a08.png rawn6a08.ppm
+./png2pnm -noraw -alpha rawn6a16.pgm ../pngsuite/basn6a16.png rawn6a16.ppm
+
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/pngminus.bat b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/pngminus.bat
index 5f8d2d4..911bb8d 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/pngminus.bat
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/pngminus.bat
@@ -1,4 +1,4 @@
-make -f makefile.tc3

-call png2pnm.bat

-call pnm2png.bat

-

+make -f makefile.tc3
+call png2pnm.bat
+call pnm2png.bat
+
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/pngminus.sh b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/pngminus.sh
index adcef55..2a0a9d8 100755
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/pngminus.sh
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/pngminus.sh
@@ -1,5 +1,5 @@
-#!/bin/sh

-make -f makefile.std

-sh png2pnm.sh

-sh pnm2png.sh

-

+#!/bin/sh
+make -f makefile.std
+sh png2pnm.sh
+sh pnm2png.sh
+
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/pnm2png.bat b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/pnm2png.bat
index 5b9977a..f756cb8 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/pnm2png.bat
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/pnm2png.bat
@@ -1,41 +1,41 @@
-REM -- grayscale

-pnm2png.exe basn0g01.pgm basn0g01.png

-pnm2png.exe basn0g02.pgm basn0g02.png

-pnm2png.exe basn0g04.pgm basn0g04.png

-pnm2png.exe basn0g08.pgm basn0g08.png

-pnm2png.exe basn0g16.pgm basn0g16.png

-REM -- full-color

-pnm2png.exe basn2c08.ppm basn2c08.png

-pnm2png.exe basn2c16.ppm basn2c16.png

-REM -- palletted

-pnm2png.exe basn3p01.ppm basn3p01.png

-pnm2png.exe basn3p02.ppm basn3p02.png

-pnm2png.exe basn3p04.ppm basn3p04.png

-pnm2png.exe basn3p08.ppm basn3p08.png

-REM -- gray with alpha-channel

-pnm2png.exe -alpha basn6a08.pgm basn4a08.pgm basn4a08.png

-pnm2png.exe -alpha basn6a16.pgm basn4a16.pgm basn4a16.png

-REM -- color with alpha-channel

-pnm2png.exe -alpha basn6a08.pgm basn6a08.ppm basn6a08.png

-pnm2png.exe -alpha basn6a16.pgm basn6a16.ppm basn6a16.png

-REM -- grayscale

-pnm2png.exe rawn0g01.pgm rawn0g01.png

-pnm2png.exe rawn0g02.pgm rawn0g02.png

-pnm2png.exe rawn0g04.pgm rawn0g04.png

-pnm2png.exe rawn0g08.pgm rawn0g08.png

-pnm2png.exe rawn0g16.pgm rawn0g16.png

-REM -- full-color

-pnm2png.exe rawn2c08.ppm rawn2c08.png

-pnm2png.exe rawn2c16.ppm rawn2c16.png

-REM -- palletted

-pnm2png.exe rawn3p01.ppm rawn3p01.png

-pnm2png.exe rawn3p02.ppm rawn3p02.png

-pnm2png.exe rawn3p04.ppm rawn3p04.png

-pnm2png.exe rawn3p08.ppm rawn3p08.png

-REM -- gray with alpha-channel

-pnm2png.exe -alpha rawn6a08.pgm rawn4a08.pgm rawn4a08.png

-pnm2png.exe -alpha rawn6a16.pgm rawn4a16.pgm rawn4a16.png

-REM -- color with alpha-channel

-pnm2png.exe -alpha rawn6a08.pgm rawn6a08.ppm rawn6a08.png

-pnm2png.exe -alpha rawn6a16.pgm rawn6a16.ppm rawn6a16.png

-

+REM -- grayscale
+pnm2png.exe basn0g01.pgm basn0g01.png
+pnm2png.exe basn0g02.pgm basn0g02.png
+pnm2png.exe basn0g04.pgm basn0g04.png
+pnm2png.exe basn0g08.pgm basn0g08.png
+pnm2png.exe basn0g16.pgm basn0g16.png
+REM -- full-color
+pnm2png.exe basn2c08.ppm basn2c08.png
+pnm2png.exe basn2c16.ppm basn2c16.png
+REM -- palletted
+pnm2png.exe basn3p01.ppm basn3p01.png
+pnm2png.exe basn3p02.ppm basn3p02.png
+pnm2png.exe basn3p04.ppm basn3p04.png
+pnm2png.exe basn3p08.ppm basn3p08.png
+REM -- gray with alpha-channel
+pnm2png.exe -alpha basn6a08.pgm basn4a08.pgm basn4a08.png
+pnm2png.exe -alpha basn6a16.pgm basn4a16.pgm basn4a16.png
+REM -- color with alpha-channel
+pnm2png.exe -alpha basn6a08.pgm basn6a08.ppm basn6a08.png
+pnm2png.exe -alpha basn6a16.pgm basn6a16.ppm basn6a16.png
+REM -- grayscale
+pnm2png.exe rawn0g01.pgm rawn0g01.png
+pnm2png.exe rawn0g02.pgm rawn0g02.png
+pnm2png.exe rawn0g04.pgm rawn0g04.png
+pnm2png.exe rawn0g08.pgm rawn0g08.png
+pnm2png.exe rawn0g16.pgm rawn0g16.png
+REM -- full-color
+pnm2png.exe rawn2c08.ppm rawn2c08.png
+pnm2png.exe rawn2c16.ppm rawn2c16.png
+REM -- palletted
+pnm2png.exe rawn3p01.ppm rawn3p01.png
+pnm2png.exe rawn3p02.ppm rawn3p02.png
+pnm2png.exe rawn3p04.ppm rawn3p04.png
+pnm2png.exe rawn3p08.ppm rawn3p08.png
+REM -- gray with alpha-channel
+pnm2png.exe -alpha rawn6a08.pgm rawn4a08.pgm rawn4a08.png
+pnm2png.exe -alpha rawn6a16.pgm rawn4a16.pgm rawn4a16.png
+REM -- color with alpha-channel
+pnm2png.exe -alpha rawn6a08.pgm rawn6a08.ppm rawn6a08.png
+pnm2png.exe -alpha rawn6a16.pgm rawn6a16.ppm rawn6a16.png
+
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/pnm2png.c b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/pnm2png.c
index 2f321cc..4cdfad8 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/pnm2png.c
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/pnm2png.c
@@ -1,533 +1,533 @@
-/*

- *  pnm2png.c --- conversion from PBM/PGM/PPM-file to PNG-file

- *  copyright (C) 1999 by Willem van Schaik <willem@schaik.com>

- *

- *  version 1.0 - 1999.10.15 - First version.

- *

- *  Permission to use, copy, modify, and distribute this software and

- *  its documentation for any purpose and without fee is hereby granted,

- *  provided that the above copyright notice appear in all copies and

- *  that both that copyright notice and this permission notice appear in

- *  supporting documentation. This software is provided "as is" without

- *  express or implied warranty.

- */

-

-#include <stdio.h>

-#include <stdlib.h>

-#ifdef __TURBOC__

-#include <mem.h>

-#include <fcntl.h>

-#endif

-

-#ifndef BOOL

-#define BOOL unsigned char

-#endif

-#ifndef TRUE

-#define TRUE (BOOL) 1

-#endif

-#ifndef FALSE

-#define FALSE (BOOL) 0

-#endif

-

-#define STDIN  0

-#define STDOUT 1

-#define STDERR 2

-

-/* to make pnm2png verbose so we can find problems (needs to be before png.h) */

-#ifndef PNG_DEBUG

-#define PNG_DEBUG 0

-#endif

-

-#include "png.h"

-

-/* Define png_jmpbuf() in case we are using a pre-1.0.6 version of libpng */

-#ifndef png_jmpbuf

-#  define png_jmpbuf(png_ptr) ((png_ptr)->jmpbuf)

-#endif

-

-/* function prototypes */

-

-int  main (int argc, char *argv[]);

-void usage ();

-BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace, BOOL alpha);

-void get_token(FILE *pnm_file, char *token);

-png_uint_32 get_data (FILE *pnm_file, int depth);

-png_uint_32 get_value (FILE *pnm_file, int depth);

-

-/*

- *  main

- */

-

-int main(int argc, char *argv[])

-{

-  FILE *fp_rd = stdin;

-  FILE *fp_al = NULL;

-  FILE *fp_wr = stdout;

-  BOOL interlace = FALSE;

-  BOOL alpha = FALSE;

-  int argi;

-

-  for (argi = 1; argi < argc; argi++)

-  {

-    if (argv[argi][0] == '-')

-    {

-      switch (argv[argi][1])

-      {

-        case 'i':

-          interlace = TRUE;

-          break;

-        case 'a':

-          alpha = TRUE;

-          argi++;

-          if ((fp_al = fopen (argv[argi], "rb")) == NULL)

-          {

-            fprintf (stderr, "PNM2PNG\n");

-            fprintf (stderr, "Error:  alpha-channel file %s does not exist\n",

-               argv[argi]);

-            exit (1);

-          }

-          break;

-        case 'h':

-        case '?':

-          usage();

-          exit(0);

-          break;

-        default:

-          fprintf (stderr, "PNM2PNG\n");

-          fprintf (stderr, "Error:  unknown option %s\n", argv[argi]);

-          usage();

-          exit(1);

-          break;

-      } /* end switch */

-    }

-    else if (fp_rd == stdin)

-    {

-      if ((fp_rd = fopen (argv[argi], "rb")) == NULL)

-      {

-        fprintf (stderr, "PNM2PNG\n");

-        fprintf (stderr, "Error:  file %s does not exist\n", argv[argi]);

-        exit (1);

-      }

-    }

-    else if (fp_wr == stdout)

-    {

-      if ((fp_wr = fopen (argv[argi], "wb")) == NULL)

-      {

-        fprintf (stderr, "PNM2PNG\n");

-        fprintf (stderr, "Error:  can not create PNG-file %s\n", argv[argi]);

-        exit (1);

-      }

-    }

-    else

-    {

-      fprintf (stderr, "PNM2PNG\n");

-      fprintf (stderr, "Error:  too many parameters\n");

-      usage();

-      exit (1);

-    }

-  } /* end for */

-

-#ifdef __TURBOC__

-  /* set stdin/stdout to binary, we're reading the PNM always! in binary format */

-  if (fp_rd == stdin)

-  {

-    setmode (STDIN, O_BINARY);

-  }

-  if (fp_wr == stdout)

-  {

-    setmode (STDOUT, O_BINARY);

-  }

-#endif

-

-  /* call the conversion program itself */

-  if (pnm2png (fp_rd, fp_wr, fp_al, interlace, alpha) == FALSE)

-  {

-    fprintf (stderr, "PNM2PNG\n");

-    fprintf (stderr, "Error:  unsuccessful converting to PNG-image\n");

-    exit (1);

-  }

-

-  /* close input file */

-  fclose (fp_rd);

-  /* close output file */

-  fclose (fp_wr);

-  /* close alpha file */

-  if (alpha)

-    fclose (fp_al);

-

-  return 0;

-}

-

-/*

- *  usage

- */

-

-void usage()

-{

-  fprintf (stderr, "PNM2PNG\n");

-  fprintf (stderr, "   by Willem van Schaik, 1999\n");

-#ifdef __TURBOC__

-  fprintf (stderr, "   for Turbo-C and Borland-C compilers\n");

-#else

-  fprintf (stderr, "   for Linux (and Unix) compilers\n");

-#endif

-  fprintf (stderr, "Usage:  pnm2png [options] <file>.<pnm> [<file>.png]\n");

-  fprintf (stderr, "   or:  ... | pnm2png [options]\n");

-  fprintf (stderr, "Options:\n");

-  fprintf (stderr, "   -i[nterlace]   write png-file with interlacing on\n");

-  fprintf (stderr, "   -a[lpha] <file>.pgm read PNG alpha channel as pgm-file\n");

-  fprintf (stderr, "   -h | -?  print this help-information\n");

-}

-

-/*

- *  pnm2png

- */

-

-BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace, BOOL alpha)

-{

-  png_struct    *png_ptr = NULL;

-  png_info      *info_ptr = NULL;

-  png_byte      *png_pixels = NULL;

-  png_byte      **row_pointers = NULL;

-  png_byte      *pix_ptr = NULL;

-  png_uint_32   row_bytes;

-

-  char          type_token[16];

-  char          width_token[16];

-  char          height_token[16];

-  char          maxval_token[16];

-  int           color_type;

-  png_uint_32   width, alpha_width;

-  png_uint_32   height, alpha_height;

-  png_uint_32   maxval;

-  int           bit_depth = 0;

-  int           channels;

-  int           alpha_depth = 0;

-  int           alpha_present;

-  int           row, col;

-  BOOL          raw, alpha_raw = FALSE;

-  png_uint_32   tmp16;

-  int           i;

-

-  /* read header of PNM file */

-

-  get_token(pnm_file, type_token);

-  if (type_token[0] != 'P')

-  {

-    return FALSE;

-  }

-  else if ((type_token[1] == '1') || (type_token[1] == '4'))

-  {

-    raw = (type_token[1] == '4');

-    color_type = PNG_COLOR_TYPE_GRAY;

-    bit_depth = 1;

-  }

-  else if ((type_token[1] == '2') || (type_token[1] == '5'))

-  {

-    raw = (type_token[1] == '5');

-    color_type = PNG_COLOR_TYPE_GRAY;

-    get_token(pnm_file, width_token);

-    sscanf (width_token, "%lu", &width);

-    get_token(pnm_file, height_token);

-    sscanf (height_token, "%lu", &height);

-    get_token(pnm_file, maxval_token);

-    sscanf (maxval_token, "%lu", &maxval);

-    if (maxval <= 1)

-      bit_depth = 1;

-    else if (maxval <= 3)

-      bit_depth = 2;

-    else if (maxval <= 15)

-      bit_depth = 4;

-    else if (maxval <= 255)

-      bit_depth = 8;

-    else /* if (maxval <= 65535) */

-      bit_depth = 16;

-  }

-  else if ((type_token[1] == '3') || (type_token[1] == '6'))

-  {

-    raw = (type_token[1] == '6');

-    color_type = PNG_COLOR_TYPE_RGB;

-    get_token(pnm_file, width_token);

-    sscanf (width_token, "%lu", &width);

-    get_token(pnm_file, height_token);

-    sscanf (height_token, "%lu", &height);

-    get_token(pnm_file, maxval_token);

-    sscanf (maxval_token, "%lu", &maxval);

-    if (maxval <= 1)

-      bit_depth = 1;

-    else if (maxval <= 3)

-      bit_depth = 2;

-    else if (maxval <= 15)

-      bit_depth = 4;

-    else if (maxval <= 255)

-      bit_depth = 8;

-    else /* if (maxval <= 65535) */

-      bit_depth = 16;

-  }

-  else

-  {

-    return FALSE;

-  }

-

-  /* read header of PGM file with alpha channel */

-

-  if (alpha)

-  {

-    if (color_type == PNG_COLOR_TYPE_GRAY)

-      color_type = PNG_COLOR_TYPE_GRAY_ALPHA;

-    if (color_type == PNG_COLOR_TYPE_RGB)

-      color_type = PNG_COLOR_TYPE_RGB_ALPHA;

-

-    get_token(alpha_file, type_token);

-    if (type_token[0] != 'P')

-    {

-      return FALSE;

-    }

-    else if ((type_token[1] == '2') || (type_token[1] == '5'))

-    {

-      alpha_raw = (type_token[1] == '5');

-      get_token(alpha_file, width_token);

-      sscanf (width_token, "%lu", &alpha_width);

-      if (alpha_width != width)

-        return FALSE;

-      get_token(alpha_file, height_token);

-      sscanf (height_token, "%lu", &alpha_height);

-      if (alpha_height != height)

-        return FALSE;

-      get_token(alpha_file, maxval_token);

-      sscanf (maxval_token, "%lu", &maxval);

-      if (maxval <= 1)

-        alpha_depth = 1;

-      else if (maxval <= 3)

-        alpha_depth = 2;

-      else if (maxval <= 15)

-        alpha_depth = 4;

-      else if (maxval <= 255)

-        alpha_depth = 8;

-      else /* if (maxval <= 65535) */

-        alpha_depth = 16;

-      if (alpha_depth != bit_depth)

-        return FALSE;

-    }

-    else

-    {

-      return FALSE;

-    }

-  } /* end if alpha */

-

-  /* calculate the number of channels and store alpha-presence */

-  if (color_type == PNG_COLOR_TYPE_GRAY)

-    channels = 1;

-  else if (color_type == PNG_COLOR_TYPE_GRAY_ALPHA)

-    channels = 2;

-  else if (color_type == PNG_COLOR_TYPE_RGB)

-    channels = 3;

-  else if (color_type == PNG_COLOR_TYPE_RGB_ALPHA)

-    channels = 4;

-  else

-    channels = 0; /* should not happen */

-

-  alpha_present = (channels - 1) % 2;

-

-  /* row_bytes is the width x number of channels x (bit-depth / 8) */

-  row_bytes = width * channels * ((bit_depth <= 8) ? 1 : 2);

-

-  if ((png_pixels = (png_byte *) malloc (row_bytes * height * sizeof (png_byte))) == NULL)

-    return FALSE;

-

-  /* read data from PNM file */

-  pix_ptr = png_pixels;

-

-  for (row = 0; row < height; row++)

-  {

-    for (col = 0; col < width; col++)

-    {

-      for (i = 0; i < (channels - alpha_present); i++)

-      {

-        if (raw)

-          *pix_ptr++ = get_data (pnm_file, bit_depth);

-        else

-          if (bit_depth <= 8)

-            *pix_ptr++ = get_value (pnm_file, bit_depth);

-          else

-          {

-            tmp16 = get_value (pnm_file, bit_depth);

-            *pix_ptr = (png_byte) ((tmp16 >> 8) & 0xFF);

-            pix_ptr++;

-            *pix_ptr = (png_byte) (tmp16 & 0xFF);

-            pix_ptr++;

-          }

-      }

-

-      if (alpha) /* read alpha-channel from pgm file */

-      {

-        if (alpha_raw)

-          *pix_ptr++ = get_data (alpha_file, alpha_depth);

-        else

-          if (alpha_depth <= 8)

-            *pix_ptr++ = get_value (alpha_file, bit_depth);

-          else

-          {

-            tmp16 = get_value (alpha_file, bit_depth);

-            *pix_ptr++ = (png_byte) ((tmp16 >> 8) & 0xFF);

-            *pix_ptr++ = (png_byte) (tmp16 & 0xFF);

-          }

-      } /* if alpha */

-

-    } /* end for col */

-  } /* end for row */

-

-  /* prepare the standard PNG structures */

-  png_ptr = png_create_write_struct (PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);

-  if (!png_ptr)

-  {

-    return FALSE;

-  }

-  info_ptr = png_create_info_struct (png_ptr);

-  if (!info_ptr)

-  {

-    png_destroy_write_struct (&png_ptr, (png_infopp) NULL);

-    return FALSE;

-  }

-

-  /* setjmp() must be called in every function that calls a PNG-reading libpng function */

-  if (setjmp (png_jmpbuf(png_ptr)))

-  {

-    png_destroy_write_struct (&png_ptr, (png_infopp) NULL);

-    return FALSE;

-  }

-

-  /* initialize the png structure */

-  png_init_io (png_ptr, png_file);

-

-  /* we're going to write more or less the same PNG as the input file */

-  png_set_IHDR (png_ptr, info_ptr, width, height, bit_depth, color_type,

-    (!interlace) ? PNG_INTERLACE_NONE : PNG_INTERLACE_ADAM7,

-    PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);

-

-  /* write the file header information */

-  png_write_info (png_ptr, info_ptr);

-

-  /* if needed we will allocate memory for an new array of row-pointers */

-  if (row_pointers == (unsigned char**) NULL)

-  {

-    if ((row_pointers = (png_byte **) malloc (height * sizeof (png_bytep))) == NULL)

-    {

-      png_destroy_write_struct (&png_ptr, (png_infopp) NULL);

-      return FALSE;

-    }

-  }

-

-  /* set the individual row_pointers to point at the correct offsets */

-  for (i = 0; i < (height); i++)

-    row_pointers[i] = png_pixels + i * row_bytes;

-

-  /* write out the entire image data in one call */

-  png_write_image (png_ptr, row_pointers);

-

-  /* write the additional chuncks to the PNG file (not really needed) */

-  png_write_end (png_ptr, info_ptr);

-

-  /* clean up after the write, and free any memory allocated */

-  png_destroy_write_struct (&png_ptr, (png_infopp) NULL);

-

-  if (row_pointers != (unsigned char**) NULL)

-    free (row_pointers);

-  if (png_pixels != (unsigned char*) NULL)

-    free (png_pixels);

-

-  return TRUE;

-} /* end of pnm2png */

-

-/*

- * get_token() - gets the first string after whitespace

- */

-

-void get_token(FILE *pnm_file, char *token)

-{

-  int i = 0;

-

-  /* remove white-space */

-  do

-  {

-    token[i] = (unsigned char) fgetc (pnm_file);

-  }

-  while ((token[i] == '\n') || (token[i] == '\r') || (token[i] == ' '));

-

-  /* read string */

-  do

-  {

-    i++;

-    token[i] = (unsigned char) fgetc (pnm_file);

-  }

-  while ((token[i] != '\n') && (token[i] != '\r') && (token[i] != ' '));

-

-  token[i] = '\0';

-

-  return;

-}

-

-/*

- * get_data() - takes first byte and converts into next pixel value,

- *        taking as much bits as defined by bit-depth and

- *        using the bit-depth to fill up a byte (0Ah -> AAh)

- */

-

-png_uint_32 get_data (FILE *pnm_file, int depth)

-{

-  static int bits_left = 0;

-  static int old_value = 0;

-  static int mask = 0;

-  int i;

-  png_uint_32 ret_value;

-

-  if (mask == 0)

-    for (i = 0; i < depth; i++)

-      mask = (mask >> 1) | 0x80;

-

-  if (bits_left <= 0)

-  {

-    old_value = fgetc (pnm_file);

-    bits_left = 8;

-  }

-

-  ret_value = old_value & mask;

-  for (i = 1; i < (8 / depth); i++)

-    ret_value = ret_value || (ret_value >> depth);

-

-  old_value = (old_value << depth) & 0xFF;

-  bits_left -= depth;

-

-  return ret_value;

-}

-

-/*

- * get_value() - takes first (numeric) string and converts into number,

- *         using the bit-depth to fill up a byte (0Ah -> AAh)

- */

-

-png_uint_32 get_value (FILE *pnm_file, int depth)

-{

-  static png_uint_32 mask = 0;

-  png_byte token[16];

-  png_uint_32 ret_value;

-  int i = 0;

-

-  if (mask == 0)

-    for (i = 0; i < depth; i++)

-      mask = (mask << 1) | 0x01;

-

-  get_token (pnm_file, (char *) token);

-  sscanf ((const char *) token, "%lu", &ret_value);

-

-  ret_value &= mask;

-

-  if (depth < 8)

-    for (i = 0; i < (8 / depth); i++)

-      ret_value = (ret_value << depth) || ret_value;

-

-  return ret_value;

-}

-

-/* end of source */

-

+/*
+ *  pnm2png.c --- conversion from PBM/PGM/PPM-file to PNG-file
+ *  copyright (C) 1999 by Willem van Schaik <willem@schaik.com>
+ *
+ *  version 1.0 - 1999.10.15 - First version.
+ *
+ *  Permission to use, copy, modify, and distribute this software and
+ *  its documentation for any purpose and without fee is hereby granted,
+ *  provided that the above copyright notice appear in all copies and
+ *  that both that copyright notice and this permission notice appear in
+ *  supporting documentation. This software is provided "as is" without
+ *  express or implied warranty.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#ifdef __TURBOC__
+#include <mem.h>
+#include <fcntl.h>
+#endif
+
+#ifndef BOOL
+#define BOOL unsigned char
+#endif
+#ifndef TRUE
+#define TRUE (BOOL) 1
+#endif
+#ifndef FALSE
+#define FALSE (BOOL) 0
+#endif
+
+#define STDIN  0
+#define STDOUT 1
+#define STDERR 2
+
+/* to make pnm2png verbose so we can find problems (needs to be before png.h) */
+#ifndef PNG_DEBUG
+#define PNG_DEBUG 0
+#endif
+
+#include "png.h"
+
+/* Define png_jmpbuf() in case we are using a pre-1.0.6 version of libpng */
+#ifndef png_jmpbuf
+#  define png_jmpbuf(png_ptr) ((png_ptr)->jmpbuf)
+#endif
+
+/* function prototypes */
+
+int  main (int argc, char *argv[]);
+void usage ();
+BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace, BOOL alpha);
+void get_token(FILE *pnm_file, char *token);
+png_uint_32 get_data (FILE *pnm_file, int depth);
+png_uint_32 get_value (FILE *pnm_file, int depth);
+
+/*
+ *  main
+ */
+
+int main(int argc, char *argv[])
+{
+  FILE *fp_rd = stdin;
+  FILE *fp_al = NULL;
+  FILE *fp_wr = stdout;
+  BOOL interlace = FALSE;
+  BOOL alpha = FALSE;
+  int argi;
+
+  for (argi = 1; argi < argc; argi++)
+  {
+    if (argv[argi][0] == '-')
+    {
+      switch (argv[argi][1])
+      {
+        case 'i':
+          interlace = TRUE;
+          break;
+        case 'a':
+          alpha = TRUE;
+          argi++;
+          if ((fp_al = fopen (argv[argi], "rb")) == NULL)
+          {
+            fprintf (stderr, "PNM2PNG\n");
+            fprintf (stderr, "Error:  alpha-channel file %s does not exist\n",
+               argv[argi]);
+            exit (1);
+          }
+          break;
+        case 'h':
+        case '?':
+          usage();
+          exit(0);
+          break;
+        default:
+          fprintf (stderr, "PNM2PNG\n");
+          fprintf (stderr, "Error:  unknown option %s\n", argv[argi]);
+          usage();
+          exit(1);
+          break;
+      } /* end switch */
+    }
+    else if (fp_rd == stdin)
+    {
+      if ((fp_rd = fopen (argv[argi], "rb")) == NULL)
+      {
+        fprintf (stderr, "PNM2PNG\n");
+        fprintf (stderr, "Error:  file %s does not exist\n", argv[argi]);
+        exit (1);
+      }
+    }
+    else if (fp_wr == stdout)
+    {
+      if ((fp_wr = fopen (argv[argi], "wb")) == NULL)
+      {
+        fprintf (stderr, "PNM2PNG\n");
+        fprintf (stderr, "Error:  can not create PNG-file %s\n", argv[argi]);
+        exit (1);
+      }
+    }
+    else
+    {
+      fprintf (stderr, "PNM2PNG\n");
+      fprintf (stderr, "Error:  too many parameters\n");
+      usage();
+      exit (1);
+    }
+  } /* end for */
+
+#ifdef __TURBOC__
+  /* set stdin/stdout to binary, we're reading the PNM always! in binary format */
+  if (fp_rd == stdin)
+  {
+    setmode (STDIN, O_BINARY);
+  }
+  if (fp_wr == stdout)
+  {
+    setmode (STDOUT, O_BINARY);
+  }
+#endif
+
+  /* call the conversion program itself */
+  if (pnm2png (fp_rd, fp_wr, fp_al, interlace, alpha) == FALSE)
+  {
+    fprintf (stderr, "PNM2PNG\n");
+    fprintf (stderr, "Error:  unsuccessful converting to PNG-image\n");
+    exit (1);
+  }
+
+  /* close input file */
+  fclose (fp_rd);
+  /* close output file */
+  fclose (fp_wr);
+  /* close alpha file */
+  if (alpha)
+    fclose (fp_al);
+
+  return 0;
+}
+
+/*
+ *  usage
+ */
+
+void usage()
+{
+  fprintf (stderr, "PNM2PNG\n");
+  fprintf (stderr, "   by Willem van Schaik, 1999\n");
+#ifdef __TURBOC__
+  fprintf (stderr, "   for Turbo-C and Borland-C compilers\n");
+#else
+  fprintf (stderr, "   for Linux (and Unix) compilers\n");
+#endif
+  fprintf (stderr, "Usage:  pnm2png [options] <file>.<pnm> [<file>.png]\n");
+  fprintf (stderr, "   or:  ... | pnm2png [options]\n");
+  fprintf (stderr, "Options:\n");
+  fprintf (stderr, "   -i[nterlace]   write png-file with interlacing on\n");
+  fprintf (stderr, "   -a[lpha] <file>.pgm read PNG alpha channel as pgm-file\n");
+  fprintf (stderr, "   -h | -?  print this help-information\n");
+}
+
+/*
+ *  pnm2png
+ */
+
+BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace, BOOL alpha)
+{
+  png_struct    *png_ptr = NULL;
+  png_info      *info_ptr = NULL;
+  png_byte      *png_pixels = NULL;
+  png_byte      **row_pointers = NULL;
+  png_byte      *pix_ptr = NULL;
+  png_uint_32   row_bytes;
+
+  char          type_token[16];
+  char          width_token[16];
+  char          height_token[16];
+  char          maxval_token[16];
+  int           color_type;
+  png_uint_32   width, alpha_width;
+  png_uint_32   height, alpha_height;
+  png_uint_32   maxval;
+  int           bit_depth = 0;
+  int           channels;
+  int           alpha_depth = 0;
+  int           alpha_present;
+  int           row, col;
+  BOOL          raw, alpha_raw = FALSE;
+  png_uint_32   tmp16;
+  int           i;
+
+  /* read header of PNM file */
+
+  get_token(pnm_file, type_token);
+  if (type_token[0] != 'P')
+  {
+    return FALSE;
+  }
+  else if ((type_token[1] == '1') || (type_token[1] == '4'))
+  {
+    raw = (type_token[1] == '4');
+    color_type = PNG_COLOR_TYPE_GRAY;
+    bit_depth = 1;
+  }
+  else if ((type_token[1] == '2') || (type_token[1] == '5'))
+  {
+    raw = (type_token[1] == '5');
+    color_type = PNG_COLOR_TYPE_GRAY;
+    get_token(pnm_file, width_token);
+    sscanf (width_token, "%lu", &width);
+    get_token(pnm_file, height_token);
+    sscanf (height_token, "%lu", &height);
+    get_token(pnm_file, maxval_token);
+    sscanf (maxval_token, "%lu", &maxval);
+    if (maxval <= 1)
+      bit_depth = 1;
+    else if (maxval <= 3)
+      bit_depth = 2;
+    else if (maxval <= 15)
+      bit_depth = 4;
+    else if (maxval <= 255)
+      bit_depth = 8;
+    else /* if (maxval <= 65535) */
+      bit_depth = 16;
+  }
+  else if ((type_token[1] == '3') || (type_token[1] == '6'))
+  {
+    raw = (type_token[1] == '6');
+    color_type = PNG_COLOR_TYPE_RGB;
+    get_token(pnm_file, width_token);
+    sscanf (width_token, "%lu", &width);
+    get_token(pnm_file, height_token);
+    sscanf (height_token, "%lu", &height);
+    get_token(pnm_file, maxval_token);
+    sscanf (maxval_token, "%lu", &maxval);
+    if (maxval <= 1)
+      bit_depth = 1;
+    else if (maxval <= 3)
+      bit_depth = 2;
+    else if (maxval <= 15)
+      bit_depth = 4;
+    else if (maxval <= 255)
+      bit_depth = 8;
+    else /* if (maxval <= 65535) */
+      bit_depth = 16;
+  }
+  else
+  {
+    return FALSE;
+  }
+
+  /* read header of PGM file with alpha channel */
+
+  if (alpha)
+  {
+    if (color_type == PNG_COLOR_TYPE_GRAY)
+      color_type = PNG_COLOR_TYPE_GRAY_ALPHA;
+    if (color_type == PNG_COLOR_TYPE_RGB)
+      color_type = PNG_COLOR_TYPE_RGB_ALPHA;
+
+    get_token(alpha_file, type_token);
+    if (type_token[0] != 'P')
+    {
+      return FALSE;
+    }
+    else if ((type_token[1] == '2') || (type_token[1] == '5'))
+    {
+      alpha_raw = (type_token[1] == '5');
+      get_token(alpha_file, width_token);
+      sscanf (width_token, "%lu", &alpha_width);
+      if (alpha_width != width)
+        return FALSE;
+      get_token(alpha_file, height_token);
+      sscanf (height_token, "%lu", &alpha_height);
+      if (alpha_height != height)
+        return FALSE;
+      get_token(alpha_file, maxval_token);
+      sscanf (maxval_token, "%lu", &maxval);
+      if (maxval <= 1)
+        alpha_depth = 1;
+      else if (maxval <= 3)
+        alpha_depth = 2;
+      else if (maxval <= 15)
+        alpha_depth = 4;
+      else if (maxval <= 255)
+        alpha_depth = 8;
+      else /* if (maxval <= 65535) */
+        alpha_depth = 16;
+      if (alpha_depth != bit_depth)
+        return FALSE;
+    }
+    else
+    {
+      return FALSE;
+    }
+  } /* end if alpha */
+
+  /* calculate the number of channels and store alpha-presence */
+  if (color_type == PNG_COLOR_TYPE_GRAY)
+    channels = 1;
+  else if (color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+    channels = 2;
+  else if (color_type == PNG_COLOR_TYPE_RGB)
+    channels = 3;
+  else if (color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+    channels = 4;
+  else
+    channels = 0; /* should not happen */
+
+  alpha_present = (channels - 1) % 2;
+
+  /* row_bytes is the width x number of channels x (bit-depth / 8) */
+  row_bytes = width * channels * ((bit_depth <= 8) ? 1 : 2);
+
+  if ((png_pixels = (png_byte *) malloc (row_bytes * height * sizeof (png_byte))) == NULL)
+    return FALSE;
+
+  /* read data from PNM file */
+  pix_ptr = png_pixels;
+
+  for (row = 0; row < height; row++)
+  {
+    for (col = 0; col < width; col++)
+    {
+      for (i = 0; i < (channels - alpha_present); i++)
+      {
+        if (raw)
+          *pix_ptr++ = get_data (pnm_file, bit_depth);
+        else
+          if (bit_depth <= 8)
+            *pix_ptr++ = get_value (pnm_file, bit_depth);
+          else
+          {
+            tmp16 = get_value (pnm_file, bit_depth);
+            *pix_ptr = (png_byte) ((tmp16 >> 8) & 0xFF);
+            pix_ptr++;
+            *pix_ptr = (png_byte) (tmp16 & 0xFF);
+            pix_ptr++;
+          }
+      }
+
+      if (alpha) /* read alpha-channel from pgm file */
+      {
+        if (alpha_raw)
+          *pix_ptr++ = get_data (alpha_file, alpha_depth);
+        else
+          if (alpha_depth <= 8)
+            *pix_ptr++ = get_value (alpha_file, bit_depth);
+          else
+          {
+            tmp16 = get_value (alpha_file, bit_depth);
+            *pix_ptr++ = (png_byte) ((tmp16 >> 8) & 0xFF);
+            *pix_ptr++ = (png_byte) (tmp16 & 0xFF);
+          }
+      } /* if alpha */
+
+    } /* end for col */
+  } /* end for row */
+
+  /* prepare the standard PNG structures */
+  png_ptr = png_create_write_struct (PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+  if (!png_ptr)
+  {
+    return FALSE;
+  }
+  info_ptr = png_create_info_struct (png_ptr);
+  if (!info_ptr)
+  {
+    png_destroy_write_struct (&png_ptr, (png_infopp) NULL);
+    return FALSE;
+  }
+
+  /* setjmp() must be called in every function that calls a PNG-reading libpng function */
+  if (setjmp (png_jmpbuf(png_ptr)))
+  {
+    png_destroy_write_struct (&png_ptr, (png_infopp) NULL);
+    return FALSE;
+  }
+
+  /* initialize the png structure */
+  png_init_io (png_ptr, png_file);
+
+  /* we're going to write more or less the same PNG as the input file */
+  png_set_IHDR (png_ptr, info_ptr, width, height, bit_depth, color_type,
+    (!interlace) ? PNG_INTERLACE_NONE : PNG_INTERLACE_ADAM7,
+    PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
+
+  /* write the file header information */
+  png_write_info (png_ptr, info_ptr);
+
+  /* if needed we will allocate memory for an new array of row-pointers */
+  if (row_pointers == (unsigned char**) NULL)
+  {
+    if ((row_pointers = (png_byte **) malloc (height * sizeof (png_bytep))) == NULL)
+    {
+      png_destroy_write_struct (&png_ptr, (png_infopp) NULL);
+      return FALSE;
+    }
+  }
+
+  /* set the individual row_pointers to point at the correct offsets */
+  for (i = 0; i < (height); i++)
+    row_pointers[i] = png_pixels + i * row_bytes;
+
+  /* write out the entire image data in one call */
+  png_write_image (png_ptr, row_pointers);
+
+  /* write the additional chuncks to the PNG file (not really needed) */
+  png_write_end (png_ptr, info_ptr);
+
+  /* clean up after the write, and free any memory allocated */
+  png_destroy_write_struct (&png_ptr, (png_infopp) NULL);
+
+  if (row_pointers != (unsigned char**) NULL)
+    free (row_pointers);
+  if (png_pixels != (unsigned char*) NULL)
+    free (png_pixels);
+
+  return TRUE;
+} /* end of pnm2png */
+
+/*
+ * get_token() - gets the first string after whitespace
+ */
+
+void get_token(FILE *pnm_file, char *token)
+{
+  int i = 0;
+
+  /* remove white-space */
+  do
+  {
+    token[i] = (unsigned char) fgetc (pnm_file);
+  }
+  while ((token[i] == '\n') || (token[i] == '\r') || (token[i] == ' '));
+
+  /* read string */
+  do
+  {
+    i++;
+    token[i] = (unsigned char) fgetc (pnm_file);
+  }
+  while ((token[i] != '\n') && (token[i] != '\r') && (token[i] != ' '));
+
+  token[i] = '\0';
+
+  return;
+}
+
+/*
+ * get_data() - takes first byte and converts into next pixel value,
+ *        taking as much bits as defined by bit-depth and
+ *        using the bit-depth to fill up a byte (0Ah -> AAh)
+ */
+
+png_uint_32 get_data (FILE *pnm_file, int depth)
+{
+  static int bits_left = 0;
+  static int old_value = 0;
+  static int mask = 0;
+  int i;
+  png_uint_32 ret_value;
+
+  if (mask == 0)
+    for (i = 0; i < depth; i++)
+      mask = (mask >> 1) | 0x80;
+
+  if (bits_left <= 0)
+  {
+    old_value = fgetc (pnm_file);
+    bits_left = 8;
+  }
+
+  ret_value = old_value & mask;
+  for (i = 1; i < (8 / depth); i++)
+    ret_value = ret_value || (ret_value >> depth);
+
+  old_value = (old_value << depth) & 0xFF;
+  bits_left -= depth;
+
+  return ret_value;
+}
+
+/*
+ * get_value() - takes first (numeric) string and converts into number,
+ *         using the bit-depth to fill up a byte (0Ah -> AAh)
+ */
+
+png_uint_32 get_value (FILE *pnm_file, int depth)
+{
+  static png_uint_32 mask = 0;
+  png_byte token[16];
+  png_uint_32 ret_value;
+  int i = 0;
+
+  if (mask == 0)
+    for (i = 0; i < depth; i++)
+      mask = (mask << 1) | 0x01;
+
+  get_token (pnm_file, (char *) token);
+  sscanf ((const char *) token, "%lu", &ret_value);
+
+  ret_value &= mask;
+
+  if (depth < 8)
+    for (i = 0; i < (8 / depth); i++)
+      ret_value = (ret_value << depth) || ret_value;
+
+  return ret_value;
+}
+
+/* end of source */
+
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/pnm2png.sh b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/pnm2png.sh
index 975f047..d79df2f 100755
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/pnm2png.sh
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/pngminus/pnm2png.sh
@@ -1,42 +1,42 @@
-#!/bin/sh

-# -- grayscale

-./pnm2png basn0g01.pgm basn0g01.png

-./pnm2png basn0g02.pgm basn0g02.png

-./pnm2png basn0g04.pgm basn0g04.png

-./pnm2png basn0g08.pgm basn0g08.png

-./pnm2png basn0g16.pgm basn0g16.png

-# -- full-color

-./pnm2png basn2c08.ppm basn2c08.png

-./pnm2png basn2c16.ppm basn2c16.png

-# -- palletted

-./pnm2png basn3p01.ppm basn3p01.png

-./pnm2png basn3p02.ppm basn3p02.png

-./pnm2png basn3p04.ppm basn3p04.png

-./pnm2png basn3p08.ppm basn3p08.png

-# -- gray with alpha-channel

-./pnm2png -alpha basn6a08.pgm basn4a08.pgm basn4a08.png

-./pnm2png -alpha basn6a16.pgm basn4a16.pgm basn4a16.png

-# -- color with alpha-channel

-./pnm2png -alpha basn6a08.pgm basn6a08.ppm basn6a08.png

-./pnm2png -alpha basn6a16.pgm basn6a16.ppm basn6a16.png

-# -- grayscale

-./pnm2png rawn0g01.pgm rawn0g01.png

-./pnm2png rawn0g02.pgm rawn0g02.png

-./pnm2png rawn0g04.pgm rawn0g04.png

-./pnm2png rawn0g08.pgm rawn0g08.png

-./pnm2png rawn0g16.pgm rawn0g16.png

-# -- full-color

-./pnm2png rawn2c08.ppm rawn2c08.png

-./pnm2png rawn2c16.ppm rawn2c16.png

-# -- palletted

-./pnm2png rawn3p01.ppm rawn3p01.png

-./pnm2png rawn3p02.ppm rawn3p02.png

-./pnm2png rawn3p04.ppm rawn3p04.png

-./pnm2png rawn3p08.ppm rawn3p08.png

-# -- gray with alpha-channel

-./pnm2png -alpha rawn6a08.pgm rawn4a08.pgm rawn4a08.png

-./pnm2png -alpha rawn6a16.pgm rawn4a16.pgm rawn4a16.png

-# -- color with alpha-channel

-./pnm2png -alpha rawn6a08.pgm rawn6a08.ppm rawn6a08.png

-./pnm2png -alpha rawn6a16.pgm rawn6a16.ppm rawn6a16.png

-

+#!/bin/sh
+# -- grayscale
+./pnm2png basn0g01.pgm basn0g01.png
+./pnm2png basn0g02.pgm basn0g02.png
+./pnm2png basn0g04.pgm basn0g04.png
+./pnm2png basn0g08.pgm basn0g08.png
+./pnm2png basn0g16.pgm basn0g16.png
+# -- full-color
+./pnm2png basn2c08.ppm basn2c08.png
+./pnm2png basn2c16.ppm basn2c16.png
+# -- palletted
+./pnm2png basn3p01.ppm basn3p01.png
+./pnm2png basn3p02.ppm basn3p02.png
+./pnm2png basn3p04.ppm basn3p04.png
+./pnm2png basn3p08.ppm basn3p08.png
+# -- gray with alpha-channel
+./pnm2png -alpha basn6a08.pgm basn4a08.pgm basn4a08.png
+./pnm2png -alpha basn6a16.pgm basn4a16.pgm basn4a16.png
+# -- color with alpha-channel
+./pnm2png -alpha basn6a08.pgm basn6a08.ppm basn6a08.png
+./pnm2png -alpha basn6a16.pgm basn6a16.ppm basn6a16.png
+# -- grayscale
+./pnm2png rawn0g01.pgm rawn0g01.png
+./pnm2png rawn0g02.pgm rawn0g02.png
+./pnm2png rawn0g04.pgm rawn0g04.png
+./pnm2png rawn0g08.pgm rawn0g08.png
+./pnm2png rawn0g16.pgm rawn0g16.png
+# -- full-color
+./pnm2png rawn2c08.ppm rawn2c08.png
+./pnm2png rawn2c16.ppm rawn2c16.png
+# -- palletted
+./pnm2png rawn3p01.ppm rawn3p01.png
+./pnm2png rawn3p02.ppm rawn3p02.png
+./pnm2png rawn3p04.ppm rawn3p04.png
+./pnm2png rawn3p08.ppm rawn3p08.png
+# -- gray with alpha-channel
+./pnm2png -alpha rawn6a08.pgm rawn4a08.pgm rawn4a08.png
+./pnm2png -alpha rawn6a16.pgm rawn4a16.pgm rawn4a16.png
+# -- color with alpha-channel
+./pnm2png -alpha rawn6a08.pgm rawn6a08.ppm rawn6a08.png
+./pnm2png -alpha rawn6a16.pgm rawn6a16.ppm rawn6a16.png
+
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/visupng/PngFile.c b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/visupng/PngFile.c
index f3e440a..ef0984e 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/visupng/PngFile.c
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/visupng/PngFile.c
@@ -1,450 +1,450 @@
-/*-------------------------------------

- *  PNGFILE.C -- Image File Functions

- *-------------------------------------

- *

- * Copyright 2000, Willem van Schaik.

- *

- * This code is released under the libpng license.

- * For conditions of distribution and use, see the disclaimer

- * and license in png.h

- */

-

-#include <windows.h>

-#include <commdlg.h>

-#include <stdio.h>

-#include <stdlib.h>

-

-#include "png.h"

-#include "pngfile.h"

-#include "cexcept.h"

-

-define_exception_type(const char *);

-extern struct exception_context the_exception_context[1];

-struct exception_context the_exception_context[1];

-png_const_charp msg;

-

-static OPENFILENAME ofn;

-

-static png_structp png_ptr = NULL;

-static png_infop info_ptr = NULL;

-

-

-/* cexcept interface */

-

-static void

-png_cexcept_error(png_structp png_ptr, png_const_charp msg)

-{

-   if(png_ptr)

-     ;

-#ifdef PNG_CONSOLE_IO_SUPPORTED

-   fprintf(stderr, "libpng error: %s\n", msg);

-#endif

-   {

-      Throw msg;

-   }

-}

-

-/* Windows open-file functions */

-

-void PngFileInitialize (HWND hwnd)

-{

-    static TCHAR szFilter[] = TEXT ("PNG Files (*.PNG)\0*.png\0")

-        TEXT ("All Files (*.*)\0*.*\0\0");

-

-    ofn.lStructSize       = sizeof (OPENFILENAME);

-    ofn.hwndOwner         = hwnd;

-    ofn.hInstance         = NULL;

-    ofn.lpstrFilter       = szFilter;

-    ofn.lpstrCustomFilter = NULL;

-    ofn.nMaxCustFilter    = 0;

-    ofn.nFilterIndex      = 0;

-    ofn.lpstrFile         = NULL;          /* Set in Open and Close functions */

-    ofn.nMaxFile          = MAX_PATH;

-    ofn.lpstrFileTitle    = NULL;          /* Set in Open and Close functions */

-    ofn.nMaxFileTitle     = MAX_PATH;

-    ofn.lpstrInitialDir   = NULL;

-    ofn.lpstrTitle        = NULL;

-    ofn.Flags             = 0;             /* Set in Open and Close functions */

-    ofn.nFileOffset       = 0;

-    ofn.nFileExtension    = 0;

-    ofn.lpstrDefExt       = TEXT ("png");

-    ofn.lCustData         = 0;

-    ofn.lpfnHook          = NULL;

-    ofn.lpTemplateName    = NULL;

-}

-

-BOOL PngFileOpenDlg (HWND hwnd, PTSTR pstrFileName, PTSTR pstrTitleName)

-{

-    ofn.hwndOwner         = hwnd;

-    ofn.lpstrFile         = pstrFileName;

-    ofn.lpstrFileTitle    = pstrTitleName;

-    ofn.Flags             = OFN_HIDEREADONLY;

-

-    return GetOpenFileName (&ofn);

-}

-

-BOOL PngFileSaveDlg (HWND hwnd, PTSTR pstrFileName, PTSTR pstrTitleName)

-{

-    ofn.hwndOwner         = hwnd;

-    ofn.lpstrFile         = pstrFileName;

-    ofn.lpstrFileTitle    = pstrTitleName;

-    ofn.Flags             = OFN_HIDEREADONLY | OFN_OVERWRITEPROMPT;

-

-    return GetSaveFileName (&ofn);

-}

-

-/* PNG image handler functions */

-

-BOOL PngLoadImage (PTSTR pstrFileName, png_byte **ppbImageData,

-                   int *piWidth, int *piHeight, int *piChannels, png_color *pBkgColor)

-{

-    static FILE        *pfFile;

-    png_byte            pbSig[8];

-    int                 iBitDepth;

-    int                 iColorType;

-    double              dGamma;

-    png_color_16       *pBackground;

-    png_uint_32         ulChannels;

-    png_uint_32         ulRowBytes;

-    png_byte           *pbImageData = *ppbImageData;

-    static png_byte   **ppbRowPointers = NULL;

-    int                 i;

-

-    /* open the PNG input file */

-

-    if (!pstrFileName)

-    {

-        *ppbImageData = pbImageData = NULL;

-        return FALSE;

-    }

-

-    if (!(pfFile = fopen(pstrFileName, "rb")))

-    {

-        *ppbImageData = pbImageData = NULL;

-        return FALSE;

-    }

-

-    /* first check the eight byte PNG signature */

-

-    fread(pbSig, 1, 8, pfFile);

-    if (png_sig_cmp(pbSig, 0, 8))

-    {

-        *ppbImageData = pbImageData = NULL;

-        return FALSE;

-    }

-

-    /* create the two png(-info) structures */

-

-    png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL,

-      (png_error_ptr)png_cexcept_error, (png_error_ptr)NULL);

-    if (!png_ptr)

-    {

-        *ppbImageData = pbImageData = NULL;

-        return FALSE;

-    }

-

-    info_ptr = png_create_info_struct(png_ptr);

-    if (!info_ptr)

-    {

-        png_destroy_read_struct(&png_ptr, NULL, NULL);

-        *ppbImageData = pbImageData = NULL;

-        return FALSE;

-    }

-

-    Try

-    {

-

-        /* initialize the png structure */

-

-#ifdef PNG_STDIO_SUPPORTED

-        png_init_io(png_ptr, pfFile);

-#else

-        png_set_read_fn(png_ptr, (png_voidp)pfFile, png_read_data);

-#endif

-

-        png_set_sig_bytes(png_ptr, 8);

-

-        /* read all PNG info up to image data */

-

-        png_read_info(png_ptr, info_ptr);

-

-        /* get width, height, bit-depth and color-type */

-

-        png_get_IHDR(png_ptr, info_ptr, piWidth, piHeight, &iBitDepth,

-            &iColorType, NULL, NULL, NULL);

-

-        /* expand images of all color-type and bit-depth to 3x8-bit RGB */

-        /* let the library process alpha, transparency, background, etc. */

-

-#ifdef PNG_READ_16_TO_8_SUPPORTED

-    if (iBitDepth == 16)

-#  ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED

-        png_set_scale_16(png_ptr);

-#  else

-        png_set_strip_16(png_ptr);

-#  endif

-#endif

-        if (iColorType == PNG_COLOR_TYPE_PALETTE)

-            png_set_expand(png_ptr);

-        if (iBitDepth < 8)

-            png_set_expand(png_ptr);

-        if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))

-            png_set_expand(png_ptr);

-        if (iColorType == PNG_COLOR_TYPE_GRAY ||

-            iColorType == PNG_COLOR_TYPE_GRAY_ALPHA)

-            png_set_gray_to_rgb(png_ptr);

-

-        /* set the background color to draw transparent and alpha images over */

-        if (png_get_bKGD(png_ptr, info_ptr, &pBackground))

-        {

-            png_set_background(png_ptr, pBackground, PNG_BACKGROUND_GAMMA_FILE, 1, 1.0);

-            pBkgColor->red   = (byte) pBackground->red;

-            pBkgColor->green = (byte) pBackground->green;

-            pBkgColor->blue  = (byte) pBackground->blue;

-        }

-        else

-        {

-            pBkgColor = NULL;

-        }

-

-        /* if required set gamma conversion */

-        if (png_get_gAMA(png_ptr, info_ptr, &dGamma))

-            png_set_gamma(png_ptr, (double) 2.2, dGamma);

-

-        /* after the transformations are registered, update info_ptr data */

-

-        png_read_update_info(png_ptr, info_ptr);

-

-        /* get again width, height and the new bit-depth and color-type */

-

-        png_get_IHDR(png_ptr, info_ptr, piWidth, piHeight, &iBitDepth,

-            &iColorType, NULL, NULL, NULL);

-

-

-        /* row_bytes is the width x number of channels */

-

-        ulRowBytes = png_get_rowbytes(png_ptr, info_ptr);

-        ulChannels = png_get_channels(png_ptr, info_ptr);

-

-        *piChannels = ulChannels;

-

-        /* now we can allocate memory to store the image */

-

-        if (pbImageData)

-        {

-            free (pbImageData);

-            pbImageData = NULL;

-        }

-        if ((pbImageData = (png_byte *) malloc(ulRowBytes * (*piHeight)

-                            * sizeof(png_byte))) == NULL)

-        {

-            png_error(png_ptr, "Visual PNG: out of memory");

-        }

-        *ppbImageData = pbImageData;

-

-        /* and allocate memory for an array of row-pointers */

-

-        if ((ppbRowPointers = (png_bytepp) malloc((*piHeight)

-                            * sizeof(png_bytep))) == NULL)

-        {

-            png_error(png_ptr, "Visual PNG: out of memory");

-        }

-

-        /* set the individual row-pointers to point at the correct offsets */

-

-        for (i = 0; i < (*piHeight); i++)

-            ppbRowPointers[i] = pbImageData + i * ulRowBytes;

-

-        /* now we can go ahead and just read the whole image */

-

-        png_read_image(png_ptr, ppbRowPointers);

-

-        /* read the additional chunks in the PNG file (not really needed) */

-

-        png_read_end(png_ptr, NULL);

-

-        /* and we're done */

-

-        free (ppbRowPointers);

-        ppbRowPointers = NULL;

-

-        /* yepp, done */

-    }

-

-    Catch (msg)

-    {

-        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);

-

-        *ppbImageData = pbImageData = NULL;

-

-        if(ppbRowPointers)

-            free (ppbRowPointers);

-

-        fclose(pfFile);

-

-        return FALSE;

-    }

-

-    fclose (pfFile);

-

-    return TRUE;

-}

-

-

-BOOL PngSaveImage (PTSTR pstrFileName, png_byte *pDiData,

-                   int iWidth, int iHeight, png_color bkgColor)

-{

-    const int           ciBitDepth = 8;

-    const int           ciChannels = 3;

-

-    static FILE        *pfFile;

-    png_uint_32         ulRowBytes;

-    static png_byte   **ppbRowPointers = NULL;

-    int                 i;

-

-    /* open the PNG output file */

-

-    if (!pstrFileName)

-        return FALSE;

-

-    if (!(pfFile = fopen(pstrFileName, "wb")))

-        return FALSE;

-

-    /* prepare the standard PNG structures */

-

-    png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL,

-      (png_error_ptr)png_cexcept_error, (png_error_ptr)NULL);

-    if (!png_ptr)

-    {

-        fclose(pfFile);

-        return FALSE;

-    }

-

-    info_ptr = png_create_info_struct(png_ptr);

-    if (!info_ptr) {

-        fclose(pfFile);

-        png_destroy_write_struct(&png_ptr, (png_infopp) NULL);

-        return FALSE;

-    }

-

-    Try

-    {

-        /* initialize the png structure */

-

-#ifdef PNG_STDIO_SUPPORTED

-        png_init_io(png_ptr, pfFile);

-#else

-        png_set_write_fn(png_ptr, (png_voidp)pfFile, png_write_data, png_flush);

-#endif

-

-        /* we're going to write a very simple 3x8-bit RGB image */

-

-        png_set_IHDR(png_ptr, info_ptr, iWidth, iHeight, ciBitDepth,

-            PNG_COLOR_TYPE_RGB, PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_BASE,

-            PNG_FILTER_TYPE_BASE);

-

-        /* write the file header information */

-

-        png_write_info(png_ptr, info_ptr);

-

-        /* swap the BGR pixels in the DiData structure to RGB */

-

-        png_set_bgr(png_ptr);

-

-        /* row_bytes is the width x number of channels */

-

-        ulRowBytes = iWidth * ciChannels;

-

-        /* we can allocate memory for an array of row-pointers */

-

-        if ((ppbRowPointers = (png_bytepp) malloc(iHeight * sizeof(png_bytep))) == NULL)

-            Throw "Visualpng: Out of memory";

-

-        /* set the individual row-pointers to point at the correct offsets */

-

-        for (i = 0; i < iHeight; i++)

-            ppbRowPointers[i] = pDiData + i * (((ulRowBytes + 3) >> 2) << 2);

-

-        /* write out the entire image data in one call */

-

-        png_write_image (png_ptr, ppbRowPointers);

-

-        /* write the additional chunks to the PNG file (not really needed) */

-

-        png_write_end(png_ptr, info_ptr);

-

-        /* and we're done */

-

-        free (ppbRowPointers);

-        ppbRowPointers = NULL;

-

-        /* clean up after the write, and free any memory allocated */

-

-        png_destroy_write_struct(&png_ptr, (png_infopp) NULL);

-

-        /* yepp, done */

-    }

-

-    Catch (msg)

-    {

-        png_destroy_write_struct(&png_ptr, (png_infopp) NULL);

-

-        if(ppbRowPointers)

-            free (ppbRowPointers);

-

-        fclose(pfFile);

-

-        return FALSE;

-    }

-

-    fclose (pfFile);

-

-    return TRUE;

-}

-

-#ifndef PNG_STDIO_SUPPORTED

-

-static void

-png_read_data(png_structp png_ptr, png_bytep data, png_size_t length)

-{

-   png_size_t check;

-

-   /* fread() returns 0 on error, so it is OK to store this in a png_size_t

-    * instead of an int, which is what fread() actually returns.

-    */

-   check = (png_size_t)fread(data, (png_size_t)1, length,

-      (FILE *)png_ptr->io_ptr);

-

-   if (check != length)

-   {

-      png_error(png_ptr, "Read Error");

-   }

-}

-

-static void

-png_write_data(png_structp png_ptr, png_bytep data, png_size_t length)

-{

-   png_uint_32 check;

-

-   check = fwrite(data, 1, length, (FILE *)(png_ptr->io_ptr));

-   if (check != length)

-   {

-      png_error(png_ptr, "Write Error");

-   }

-}

-

-static void

-png_flush(png_structp png_ptr)

-{

-   FILE *io_ptr;

-   io_ptr = (FILE *)CVT_PTR((png_ptr->io_ptr));

-   if (io_ptr != NULL)

-      fflush(io_ptr);

-}

-

-#endif

-

-/*-----------------

- *  end of source

- *-----------------

- */

+/*-------------------------------------
+ *  PNGFILE.C -- Image File Functions
+ *-------------------------------------
+ *
+ * Copyright 2000, Willem van Schaik.
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ */
+
+#include <windows.h>
+#include <commdlg.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "png.h"
+#include "pngfile.h"
+#include "cexcept.h"
+
+define_exception_type(const char *);
+extern struct exception_context the_exception_context[1];
+struct exception_context the_exception_context[1];
+png_const_charp msg;
+
+static OPENFILENAME ofn;
+
+static png_structp png_ptr = NULL;
+static png_infop info_ptr = NULL;
+
+
+/* cexcept interface */
+
+static void
+png_cexcept_error(png_structp png_ptr, png_const_charp msg)
+{
+   if(png_ptr)
+     ;
+#ifdef PNG_CONSOLE_IO_SUPPORTED
+   fprintf(stderr, "libpng error: %s\n", msg);
+#endif
+   {
+      Throw msg;
+   }
+}
+
+/* Windows open-file functions */
+
+void PngFileInitialize (HWND hwnd)
+{
+    static TCHAR szFilter[] = TEXT ("PNG Files (*.PNG)\0*.png\0")
+        TEXT ("All Files (*.*)\0*.*\0\0");
+
+    ofn.lStructSize       = sizeof (OPENFILENAME);
+    ofn.hwndOwner         = hwnd;
+    ofn.hInstance         = NULL;
+    ofn.lpstrFilter       = szFilter;
+    ofn.lpstrCustomFilter = NULL;
+    ofn.nMaxCustFilter    = 0;
+    ofn.nFilterIndex      = 0;
+    ofn.lpstrFile         = NULL;          /* Set in Open and Close functions */
+    ofn.nMaxFile          = MAX_PATH;
+    ofn.lpstrFileTitle    = NULL;          /* Set in Open and Close functions */
+    ofn.nMaxFileTitle     = MAX_PATH;
+    ofn.lpstrInitialDir   = NULL;
+    ofn.lpstrTitle        = NULL;
+    ofn.Flags             = 0;             /* Set in Open and Close functions */
+    ofn.nFileOffset       = 0;
+    ofn.nFileExtension    = 0;
+    ofn.lpstrDefExt       = TEXT ("png");
+    ofn.lCustData         = 0;
+    ofn.lpfnHook          = NULL;
+    ofn.lpTemplateName    = NULL;
+}
+
+BOOL PngFileOpenDlg (HWND hwnd, PTSTR pstrFileName, PTSTR pstrTitleName)
+{
+    ofn.hwndOwner         = hwnd;
+    ofn.lpstrFile         = pstrFileName;
+    ofn.lpstrFileTitle    = pstrTitleName;
+    ofn.Flags             = OFN_HIDEREADONLY;
+
+    return GetOpenFileName (&ofn);
+}
+
+BOOL PngFileSaveDlg (HWND hwnd, PTSTR pstrFileName, PTSTR pstrTitleName)
+{
+    ofn.hwndOwner         = hwnd;
+    ofn.lpstrFile         = pstrFileName;
+    ofn.lpstrFileTitle    = pstrTitleName;
+    ofn.Flags             = OFN_HIDEREADONLY | OFN_OVERWRITEPROMPT;
+
+    return GetSaveFileName (&ofn);
+}
+
+/* PNG image handler functions */
+
+BOOL PngLoadImage (PTSTR pstrFileName, png_byte **ppbImageData,
+                   int *piWidth, int *piHeight, int *piChannels, png_color *pBkgColor)
+{
+    static FILE        *pfFile;
+    png_byte            pbSig[8];
+    int                 iBitDepth;
+    int                 iColorType;
+    double              dGamma;
+    png_color_16       *pBackground;
+    png_uint_32         ulChannels;
+    png_uint_32         ulRowBytes;
+    png_byte           *pbImageData = *ppbImageData;
+    static png_byte   **ppbRowPointers = NULL;
+    int                 i;
+
+    /* open the PNG input file */
+
+    if (!pstrFileName)
+    {
+        *ppbImageData = pbImageData = NULL;
+        return FALSE;
+    }
+
+    if (!(pfFile = fopen(pstrFileName, "rb")))
+    {
+        *ppbImageData = pbImageData = NULL;
+        return FALSE;
+    }
+
+    /* first check the eight byte PNG signature */
+
+    fread(pbSig, 1, 8, pfFile);
+    if (png_sig_cmp(pbSig, 0, 8))
+    {
+        *ppbImageData = pbImageData = NULL;
+        return FALSE;
+    }
+
+    /* create the two png(-info) structures */
+
+    png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL,
+      (png_error_ptr)png_cexcept_error, (png_error_ptr)NULL);
+    if (!png_ptr)
+    {
+        *ppbImageData = pbImageData = NULL;
+        return FALSE;
+    }
+
+    info_ptr = png_create_info_struct(png_ptr);
+    if (!info_ptr)
+    {
+        png_destroy_read_struct(&png_ptr, NULL, NULL);
+        *ppbImageData = pbImageData = NULL;
+        return FALSE;
+    }
+
+    Try
+    {
+
+        /* initialize the png structure */
+
+#ifdef PNG_STDIO_SUPPORTED
+        png_init_io(png_ptr, pfFile);
+#else
+        png_set_read_fn(png_ptr, (png_voidp)pfFile, png_read_data);
+#endif
+
+        png_set_sig_bytes(png_ptr, 8);
+
+        /* read all PNG info up to image data */
+
+        png_read_info(png_ptr, info_ptr);
+
+        /* get width, height, bit-depth and color-type */
+
+        png_get_IHDR(png_ptr, info_ptr, piWidth, piHeight, &iBitDepth,
+            &iColorType, NULL, NULL, NULL);
+
+        /* expand images of all color-type and bit-depth to 3x8-bit RGB */
+        /* let the library process alpha, transparency, background, etc. */
+
+#ifdef PNG_READ_16_TO_8_SUPPORTED
+    if (iBitDepth == 16)
+#  ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
+        png_set_scale_16(png_ptr);
+#  else
+        png_set_strip_16(png_ptr);
+#  endif
+#endif
+        if (iColorType == PNG_COLOR_TYPE_PALETTE)
+            png_set_expand(png_ptr);
+        if (iBitDepth < 8)
+            png_set_expand(png_ptr);
+        if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))
+            png_set_expand(png_ptr);
+        if (iColorType == PNG_COLOR_TYPE_GRAY ||
+            iColorType == PNG_COLOR_TYPE_GRAY_ALPHA)
+            png_set_gray_to_rgb(png_ptr);
+
+        /* set the background color to draw transparent and alpha images over */
+        if (png_get_bKGD(png_ptr, info_ptr, &pBackground))
+        {
+            png_set_background(png_ptr, pBackground, PNG_BACKGROUND_GAMMA_FILE, 1, 1.0);
+            pBkgColor->red   = (byte) pBackground->red;
+            pBkgColor->green = (byte) pBackground->green;
+            pBkgColor->blue  = (byte) pBackground->blue;
+        }
+        else
+        {
+            pBkgColor = NULL;
+        }
+
+        /* if required set gamma conversion */
+        if (png_get_gAMA(png_ptr, info_ptr, &dGamma))
+            png_set_gamma(png_ptr, (double) 2.2, dGamma);
+
+        /* after the transformations are registered, update info_ptr data */
+
+        png_read_update_info(png_ptr, info_ptr);
+
+        /* get again width, height and the new bit-depth and color-type */
+
+        png_get_IHDR(png_ptr, info_ptr, piWidth, piHeight, &iBitDepth,
+            &iColorType, NULL, NULL, NULL);
+
+
+        /* row_bytes is the width x number of channels */
+
+        ulRowBytes = png_get_rowbytes(png_ptr, info_ptr);
+        ulChannels = png_get_channels(png_ptr, info_ptr);
+
+        *piChannels = ulChannels;
+
+        /* now we can allocate memory to store the image */
+
+        if (pbImageData)
+        {
+            free (pbImageData);
+            pbImageData = NULL;
+        }
+        if ((pbImageData = (png_byte *) malloc(ulRowBytes * (*piHeight)
+                            * sizeof(png_byte))) == NULL)
+        {
+            png_error(png_ptr, "Visual PNG: out of memory");
+        }
+        *ppbImageData = pbImageData;
+
+        /* and allocate memory for an array of row-pointers */
+
+        if ((ppbRowPointers = (png_bytepp) malloc((*piHeight)
+                            * sizeof(png_bytep))) == NULL)
+        {
+            png_error(png_ptr, "Visual PNG: out of memory");
+        }
+
+        /* set the individual row-pointers to point at the correct offsets */
+
+        for (i = 0; i < (*piHeight); i++)
+            ppbRowPointers[i] = pbImageData + i * ulRowBytes;
+
+        /* now we can go ahead and just read the whole image */
+
+        png_read_image(png_ptr, ppbRowPointers);
+
+        /* read the additional chunks in the PNG file (not really needed) */
+
+        png_read_end(png_ptr, NULL);
+
+        /* and we're done */
+
+        free (ppbRowPointers);
+        ppbRowPointers = NULL;
+
+        /* yepp, done */
+    }
+
+    Catch (msg)
+    {
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+
+        *ppbImageData = pbImageData = NULL;
+
+        if(ppbRowPointers)
+            free (ppbRowPointers);
+
+        fclose(pfFile);
+
+        return FALSE;
+    }
+
+    fclose (pfFile);
+
+    return TRUE;
+}
+
+
+BOOL PngSaveImage (PTSTR pstrFileName, png_byte *pDiData,
+                   int iWidth, int iHeight, png_color bkgColor)
+{
+    const int           ciBitDepth = 8;
+    const int           ciChannels = 3;
+
+    static FILE        *pfFile;
+    png_uint_32         ulRowBytes;
+    static png_byte   **ppbRowPointers = NULL;
+    int                 i;
+
+    /* open the PNG output file */
+
+    if (!pstrFileName)
+        return FALSE;
+
+    if (!(pfFile = fopen(pstrFileName, "wb")))
+        return FALSE;
+
+    /* prepare the standard PNG structures */
+
+    png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL,
+      (png_error_ptr)png_cexcept_error, (png_error_ptr)NULL);
+    if (!png_ptr)
+    {
+        fclose(pfFile);
+        return FALSE;
+    }
+
+    info_ptr = png_create_info_struct(png_ptr);
+    if (!info_ptr) {
+        fclose(pfFile);
+        png_destroy_write_struct(&png_ptr, (png_infopp) NULL);
+        return FALSE;
+    }
+
+    Try
+    {
+        /* initialize the png structure */
+
+#ifdef PNG_STDIO_SUPPORTED
+        png_init_io(png_ptr, pfFile);
+#else
+        png_set_write_fn(png_ptr, (png_voidp)pfFile, png_write_data, png_flush);
+#endif
+
+        /* we're going to write a very simple 3x8-bit RGB image */
+
+        png_set_IHDR(png_ptr, info_ptr, iWidth, iHeight, ciBitDepth,
+            PNG_COLOR_TYPE_RGB, PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_BASE,
+            PNG_FILTER_TYPE_BASE);
+
+        /* write the file header information */
+
+        png_write_info(png_ptr, info_ptr);
+
+        /* swap the BGR pixels in the DiData structure to RGB */
+
+        png_set_bgr(png_ptr);
+
+        /* row_bytes is the width x number of channels */
+
+        ulRowBytes = iWidth * ciChannels;
+
+        /* we can allocate memory for an array of row-pointers */
+
+        if ((ppbRowPointers = (png_bytepp) malloc(iHeight * sizeof(png_bytep))) == NULL)
+            Throw "Visualpng: Out of memory";
+
+        /* set the individual row-pointers to point at the correct offsets */
+
+        for (i = 0; i < iHeight; i++)
+            ppbRowPointers[i] = pDiData + i * (((ulRowBytes + 3) >> 2) << 2);
+
+        /* write out the entire image data in one call */
+
+        png_write_image (png_ptr, ppbRowPointers);
+
+        /* write the additional chunks to the PNG file (not really needed) */
+
+        png_write_end(png_ptr, info_ptr);
+
+        /* and we're done */
+
+        free (ppbRowPointers);
+        ppbRowPointers = NULL;
+
+        /* clean up after the write, and free any memory allocated */
+
+        png_destroy_write_struct(&png_ptr, (png_infopp) NULL);
+
+        /* yepp, done */
+    }
+
+    Catch (msg)
+    {
+        png_destroy_write_struct(&png_ptr, (png_infopp) NULL);
+
+        if(ppbRowPointers)
+            free (ppbRowPointers);
+
+        fclose(pfFile);
+
+        return FALSE;
+    }
+
+    fclose (pfFile);
+
+    return TRUE;
+}
+
+#ifndef PNG_STDIO_SUPPORTED
+
+static void
+png_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
+{
+   png_size_t check;
+
+   /* fread() returns 0 on error, so it is OK to store this in a png_size_t
+    * instead of an int, which is what fread() actually returns.
+    */
+   check = (png_size_t)fread(data, (png_size_t)1, length,
+      (FILE *)png_ptr->io_ptr);
+
+   if (check != length)
+   {
+      png_error(png_ptr, "Read Error");
+   }
+}
+
+static void
+png_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
+{
+   png_uint_32 check;
+
+   check = fwrite(data, 1, length, (FILE *)(png_ptr->io_ptr));
+   if (check != length)
+   {
+      png_error(png_ptr, "Write Error");
+   }
+}
+
+static void
+png_flush(png_structp png_ptr)
+{
+   FILE *io_ptr;
+   io_ptr = (FILE *)CVT_PTR((png_ptr->io_ptr));
+   if (io_ptr != NULL)
+      fflush(io_ptr);
+}
+
+#endif
+
+/*-----------------
+ *  end of source
+ *-----------------
+ */
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/visupng/PngFile.h b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/visupng/PngFile.h
index 66f8472..32181a4 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/visupng/PngFile.h
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/visupng/PngFile.h
@@ -1,30 +1,30 @@
-/*------------------------------------------*/

-/*  PNGFILE.H -- Header File for pngfile.c*/

-/*------------------------------------------*/

-

-/* Copyright 2000, Willem van Schaik.*/

-

-/* This code is released under the libpng license.*/

-/* For conditions of distribution and use, see the disclaimer*/

-/* and license in png.h*/

-

-#include <stdio.h>

-#include <stdlib.h>

-#include <string.h>

-#include <windows.h>

-

-void PngFileInitialize (HWND hwnd) ;

-BOOL PngFileOpenDlg (HWND hwnd, PTSTR pstrFileName, PTSTR pstrTitleName) ;

-BOOL PngFileSaveDlg (HWND hwnd, PTSTR pstrFileName, PTSTR pstrTitleName) ;

-

-BOOL PngLoadImage (PTSTR pstrFileName, png_byte **ppbImageData, 

-                   int *piWidth, int *piHeight, int *piChannels, png_color *pBkgColor);

-BOOL PngSaveImage (PTSTR pstrFileName, png_byte *pDiData,

-                   int iWidth, int iHeight, png_color BkgColor);

-

-#ifndef PNG_STDIO_SUPPORTED

-static void png_read_data(png_structp png_ptr, png_bytep data, png_size_t length);

-static void png_write_data(png_structp png_ptr, png_bytep data, png_size_t length);

-static void png_flush(png_structp png_ptr);

-#endif

-

+/*------------------------------------------*/
+/*  PNGFILE.H -- Header File for pngfile.c*/
+/*------------------------------------------*/
+
+/* Copyright 2000, Willem van Schaik.*/
+
+/* This code is released under the libpng license.*/
+/* For conditions of distribution and use, see the disclaimer*/
+/* and license in png.h*/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <windows.h>
+
+void PngFileInitialize (HWND hwnd) ;
+BOOL PngFileOpenDlg (HWND hwnd, PTSTR pstrFileName, PTSTR pstrTitleName) ;
+BOOL PngFileSaveDlg (HWND hwnd, PTSTR pstrFileName, PTSTR pstrTitleName) ;
+
+BOOL PngLoadImage (PTSTR pstrFileName, png_byte **ppbImageData, 
+                   int *piWidth, int *piHeight, int *piChannels, png_color *pBkgColor);
+BOOL PngSaveImage (PTSTR pstrFileName, png_byte *pDiData,
+                   int iWidth, int iHeight, png_color BkgColor);
+
+#ifndef PNG_STDIO_SUPPORTED
+static void png_read_data(png_structp png_ptr, png_bytep data, png_size_t length);
+static void png_write_data(png_structp png_ptr, png_bytep data, png_size_t length);
+static void png_flush(png_structp png_ptr);
+#endif
+
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/visupng/README.txt b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/visupng/README.txt
index 7291bb2..72c5cba 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/visupng/README.txt
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/visupng/README.txt
@@ -1,61 +1,61 @@
-Microsoft Developer Studio Build File, Format Version 6.00 for VisualPng

-------------------------------------------------------------------------

-

-Copyright 2000, Willem van Schaik.

-

-This code is released under the libpng license.

-For conditions of distribution and use, see the disclaimer

-and license in png.h

-

-As a PNG .dll demo VisualPng is finished. More features would only hinder

-the program's objective. However, further extensions (like support for other

-graphics formats) are in development. To get these, or for pre-compiled

-binaries, go to "http://www.schaik.com/png/visualpng.html".

-

-------------------------------------------------------------------------

-

-Assumes that

-

-   libpng DLLs and LIBs are in ..\..\projects\msvc\win32\libpng

-   zlib DLLs and LIBs are in   ..\..\projects\msvc\win32\zlib

-   libpng header files are in  ..\..\..\libpng

-   zlib header files are in    ..\..\..\zlib

-   the pngsuite images are in  ..\pngsuite

-

-To build:

-

-1) On the main menu Select "Build|Set Active configuration".

-   Choose the configuration that corresponds to the library you want to test.

-   This library must have been built using the libpng MS project located in

-   the "..\..\mscv" subdirectory.

-

-2) Select "Build|Clean"

-

-3) Select "Build|Rebuild All"

-

-4) After compiling and linking VisualPng will be started to view an image

-   from the PngSuite directory.  Press Ctrl-N (and Ctrl-V) for other images.

-

-

-To install:

-

-When distributing VisualPng (or a further development) the following options

-are available:

-

-1) Build the program with the configuration "Win32 LIB" and you only need to

-   include the executable from the ./lib directory in your distribution.

-

-2) Build the program with the configuration "Win32 DLL" and you need to put

-   in your distribution the executable from the ./dll directory and the dll's

-   libpng1.dll, zlib.dll and msvcrt.dll.  These need to be in the user's PATH.

-

-

-Willem van Schaik

-Calgary, June 6th 2000

-

-P.S. VisualPng was written based on preliminary work of:

-

-    - Simon-Pierre Cadieux

-    - Glenn Randers-Pehrson

-    - Greg Roelofs

-

+Microsoft Developer Studio Build File, Format Version 6.00 for VisualPng
+------------------------------------------------------------------------
+
+Copyright 2000, Willem van Schaik.
+
+This code is released under the libpng license.
+For conditions of distribution and use, see the disclaimer
+and license in png.h
+
+As a PNG .dll demo VisualPng is finished. More features would only hinder
+the program's objective. However, further extensions (like support for other
+graphics formats) are in development. To get these, or for pre-compiled
+binaries, go to "http://www.schaik.com/png/visualpng.html".
+
+------------------------------------------------------------------------
+
+Assumes that
+
+   libpng DLLs and LIBs are in ..\..\projects\msvc\win32\libpng
+   zlib DLLs and LIBs are in   ..\..\projects\msvc\win32\zlib
+   libpng header files are in  ..\..\..\libpng
+   zlib header files are in    ..\..\..\zlib
+   the pngsuite images are in  ..\pngsuite
+
+To build:
+
+1) On the main menu Select "Build|Set Active configuration".
+   Choose the configuration that corresponds to the library you want to test.
+   This library must have been built using the libpng MS project located in
+   the "..\..\mscv" subdirectory.
+
+2) Select "Build|Clean"
+
+3) Select "Build|Rebuild All"
+
+4) After compiling and linking VisualPng will be started to view an image
+   from the PngSuite directory.  Press Ctrl-N (and Ctrl-V) for other images.
+
+
+To install:
+
+When distributing VisualPng (or a further development) the following options
+are available:
+
+1) Build the program with the configuration "Win32 LIB" and you only need to
+   include the executable from the ./lib directory in your distribution.
+
+2) Build the program with the configuration "Win32 DLL" and you need to put
+   in your distribution the executable from the ./dll directory and the dll's
+   libpng1.dll, zlib.dll and msvcrt.dll.  These need to be in the user's PATH.
+
+
+Willem van Schaik
+Calgary, June 6th 2000
+
+P.S. VisualPng was written based on preliminary work of:
+
+    - Simon-Pierre Cadieux
+    - Glenn Randers-Pehrson
+    - Greg Roelofs
+
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/visupng/VisualPng.c b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/visupng/VisualPng.c
index e672ce0..009f120 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/visupng/VisualPng.c
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/visupng/VisualPng.c
@@ -1,969 +1,969 @@
-/*------------------------------------

- *  VisualPng.C -- Shows a PNG image

- *------------------------------------

- *

- * Copyright 2000, Willem van Schaik.

- *

- * This code is released under the libpng license.

- * For conditions of distribution and use, see the disclaimer

- * and license in png.h

- */

-

-/* switches */

-

-/* defines */

-

-#define PROGNAME  "VisualPng"

-#define LONGNAME  "Win32 Viewer for PNG-files"

-#define VERSION   "1.0 of 2000 June 07"

-

-/* constants */

-

-#define MARGIN 8

-

-/* standard includes */

-

-#include <stdio.h>

-#include <stdlib.h>

-#include <string.h>

-#include <windows.h>

-

-/* application includes */

-

-#include "png.h"

-#include "pngfile.h"

-#include "resource.h"

-

-/* macros */

-

-/* function prototypes */

-

-LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM);

-BOOL    CALLBACK AboutDlgProc (HWND, UINT, WPARAM, LPARAM) ;

-

-BOOL CenterAbout (HWND hwndChild, HWND hwndParent);

-

-BOOL BuildPngList (PTSTR pstrPathName, TCHAR **ppFileList, int *pFileCount,

-        int *pFileIndex);

-

-BOOL SearchPngList (TCHAR *pFileList, int FileCount, int *pFileIndex,

-        PTSTR pstrPrevName, PTSTR pstrNextName);

-

-BOOL LoadImageFile(HWND hwnd, PTSTR pstrPathName,

-        png_byte **ppbImage, int *pxImgSize, int *pyImgSize, int *piChannels,

-        png_color *pBkgColor);

-

-BOOL DisplayImage (HWND hwnd, BYTE **ppDib,

-        BYTE **ppDiData, int cxWinSize, int cyWinSize,

-        BYTE *pbImage, int cxImgSize, int cyImgSize, int cImgChannels,

-        BOOL bStretched);

-

-BOOL InitBitmap (

-        BYTE *pDiData, int cxWinSize, int cyWinSize);

-

-BOOL FillBitmap (

-        BYTE *pDiData, int cxWinSize, int cyWinSize,

-        BYTE *pbImage, int cxImgSize, int cyImgSize, int cImgChannels,

-        BOOL bStretched);

-

-/* a few global variables */

-

-static char *szProgName = PROGNAME;

-static char *szAppName = LONGNAME;

-static char *szIconName = PROGNAME;

-static char szCmdFileName [MAX_PATH];

-

-/* MAIN routine */

-

-int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,

-                    PSTR szCmdLine, int iCmdShow)

-{

-    HACCEL   hAccel;

-    HWND     hwnd;

-    MSG      msg;

-    WNDCLASS wndclass;

-    int ixBorders, iyBorders;

-

-    wndclass.style         = CS_HREDRAW | CS_VREDRAW;

-    wndclass.lpfnWndProc   = WndProc;

-    wndclass.cbClsExtra    = 0;

-    wndclass.cbWndExtra    = 0;

-    wndclass.hInstance     = hInstance;

-    wndclass.hIcon         = LoadIcon (hInstance, szIconName) ;

-    wndclass.hCursor       = LoadCursor (NULL, IDC_ARROW);

-    wndclass.hbrBackground = NULL; /* (HBRUSH) GetStockObject (GRAY_BRUSH); */

-    wndclass.lpszMenuName  = szProgName;

-    wndclass.lpszClassName = szProgName;

-

-    if (!RegisterClass (&wndclass))

-    {

-        MessageBox (NULL, TEXT ("Error: this program requires Windows NT!"),

-            szProgName, MB_ICONERROR);

-        return 0;

-    }

-

-    /* if filename given on commandline, store it */

-    if ((szCmdLine != NULL) && (*szCmdLine != '\0'))

-        if (szCmdLine[0] == '"')

-            strncpy (szCmdFileName, szCmdLine + 1, strlen(szCmdLine) - 2);

-        else

-            strcpy (szCmdFileName, szCmdLine);

-    else

-        strcpy (szCmdFileName, "");

-

-    /* calculate size of window-borders */

-    ixBorders = 2 * (GetSystemMetrics (SM_CXBORDER) +

-                     GetSystemMetrics (SM_CXDLGFRAME));

-    iyBorders = 2 * (GetSystemMetrics (SM_CYBORDER) +

-                     GetSystemMetrics (SM_CYDLGFRAME)) +

-                     GetSystemMetrics (SM_CYCAPTION) +

-                     GetSystemMetrics (SM_CYMENUSIZE) +

-                     1; /* WvS: don't ask me why?  */

-

-    hwnd = CreateWindow (szProgName, szAppName,

-        WS_OVERLAPPEDWINDOW,

-        CW_USEDEFAULT, CW_USEDEFAULT,

-        512 + 2 * MARGIN + ixBorders, 384 + 2 * MARGIN + iyBorders,

-/*      CW_USEDEFAULT, CW_USEDEFAULT, */

-        NULL, NULL, hInstance, NULL);

-

-    ShowWindow (hwnd, iCmdShow);

-    UpdateWindow (hwnd);

-

-    hAccel = LoadAccelerators (hInstance, szProgName);

-

-    while (GetMessage (&msg, NULL, 0, 0))

-    {

-        if (!TranslateAccelerator (hwnd, hAccel, &msg))

-        {

-            TranslateMessage (&msg);

-            DispatchMessage (&msg);

-        }

-    }

-    return msg.wParam;

-}

-

-LRESULT CALLBACK WndProc (HWND hwnd, UINT message, WPARAM wParam,

-        LPARAM lParam)

-{

-    static HINSTANCE          hInstance ;

-    static HDC                hdc;

-    static PAINTSTRUCT        ps;

-    static HMENU              hMenu;

-

-    static BITMAPFILEHEADER  *pbmfh;

-    static BITMAPINFOHEADER  *pbmih;

-    static BYTE              *pbImage;

-    static int                cxWinSize, cyWinSize;

-    static int                cxImgSize, cyImgSize;

-    static int                cImgChannels;

-    static png_color          bkgColor = {127, 127, 127};

-

-    static BOOL               bStretched = TRUE;

-

-    static BYTE              *pDib = NULL;

-    static BYTE              *pDiData = NULL;

-

-    static TCHAR              szImgPathName [MAX_PATH];

-    static TCHAR              szTitleName [MAX_PATH];

-

-    static TCHAR             *pPngFileList = NULL;

-    static int                iPngFileCount;

-    static int                iPngFileIndex;

-

-    BOOL                      bOk;

-

-    switch (message)

-    {

-    case WM_CREATE:

-        hInstance = ((LPCREATESTRUCT) lParam)->hInstance ;

-        PngFileInitialize (hwnd);

-

-        strcpy (szImgPathName, "");

-

-        /* in case we process file given on command-line */

-

-        if (szCmdFileName[0] != '\0')

-        {

-            strcpy (szImgPathName, szCmdFileName);

-

-            /* read the other png-files in the directory for later */

-            /* next/previous commands */

-

-            BuildPngList (szImgPathName, &pPngFileList, &iPngFileCount,

-                          &iPngFileIndex);

-

-            /* load the image from file */

-

-            if (!LoadImageFile (hwnd, szImgPathName,

-                &pbImage, &cxImgSize, &cyImgSize, &cImgChannels, &bkgColor))

-                return 0;

-

-            /* invalidate the client area for later update */

-

-            InvalidateRect (hwnd, NULL, TRUE);

-

-            /* display the PNG into the DIBitmap */

-

-            DisplayImage (hwnd, &pDib, &pDiData, cxWinSize, cyWinSize,

-                pbImage, cxImgSize, cyImgSize, cImgChannels, bStretched);

-        }

-

-        return 0;

-

-    case WM_SIZE:

-        cxWinSize = LOWORD (lParam);

-        cyWinSize = HIWORD (lParam);

-

-        /* invalidate the client area for later update */

-

-        InvalidateRect (hwnd, NULL, TRUE);

-

-        /* display the PNG into the DIBitmap */

-

-        DisplayImage (hwnd, &pDib, &pDiData, cxWinSize, cyWinSize,

-            pbImage, cxImgSize, cyImgSize, cImgChannels, bStretched);

-

-        return 0;

-

-    case WM_INITMENUPOPUP:

-        hMenu = GetMenu (hwnd);

-

-        if (pbImage)

-            EnableMenuItem (hMenu, IDM_FILE_SAVE, MF_ENABLED);

-        else

-            EnableMenuItem (hMenu, IDM_FILE_SAVE, MF_GRAYED);

-

-        return 0;

-

-    case WM_COMMAND:

-        hMenu = GetMenu (hwnd);

-

-        switch (LOWORD (wParam))

-        {

-        case IDM_FILE_OPEN:

-

-            /* show the File Open dialog box */

-

-            if (!PngFileOpenDlg (hwnd, szImgPathName, szTitleName))

-                return 0;

-

-            /* read the other png-files in the directory for later */

-            /* next/previous commands */

-

-            BuildPngList (szImgPathName, &pPngFileList, &iPngFileCount,

-                          &iPngFileIndex);

-

-            /* load the image from file */

-

-            if (!LoadImageFile (hwnd, szImgPathName,

-                &pbImage, &cxImgSize, &cyImgSize, &cImgChannels, &bkgColor))

-                return 0;

-

-            /* invalidate the client area for later update */

-

-            InvalidateRect (hwnd, NULL, TRUE);

-

-            /* display the PNG into the DIBitmap */

-

-            DisplayImage (hwnd, &pDib, &pDiData, cxWinSize, cyWinSize,

-                pbImage, cxImgSize, cyImgSize, cImgChannels, bStretched);

-

-            return 0;

-

-        case IDM_FILE_SAVE:

-

-            /* show the File Save dialog box */

-

-            if (!PngFileSaveDlg (hwnd, szImgPathName, szTitleName))

-                return 0;

-

-            /* save the PNG to a disk file */

-

-            SetCursor (LoadCursor (NULL, IDC_WAIT));

-            ShowCursor (TRUE);

-

-            bOk = PngSaveImage (szImgPathName, pDiData, cxWinSize, cyWinSize,

-                  bkgColor);

-

-            ShowCursor (FALSE);

-            SetCursor (LoadCursor (NULL, IDC_ARROW));

-

-            if (!bOk)

-                MessageBox (hwnd, TEXT ("Error in saving the PNG image"),

-                szProgName, MB_ICONEXCLAMATION | MB_OK);

-            return 0;

-

-        case IDM_FILE_NEXT:

-

-            /* read next entry in the directory */

-

-            if (SearchPngList (pPngFileList, iPngFileCount, &iPngFileIndex,

-                NULL, szImgPathName))

-            {

-                if (strcmp (szImgPathName, "") == 0)

-                    return 0;

-

-                /* load the image from file */

-

-                if (!LoadImageFile (hwnd, szImgPathName, &pbImage,

-                        &cxImgSize, &cyImgSize, &cImgChannels, &bkgColor))

-                    return 0;

-

-                /* invalidate the client area for later update */

-

-                InvalidateRect (hwnd, NULL, TRUE);

-

-                /* display the PNG into the DIBitmap */

-

-                DisplayImage (hwnd, &pDib, &pDiData, cxWinSize, cyWinSize,

-                    pbImage, cxImgSize, cyImgSize, cImgChannels, bStretched);

-            }

-

-            return 0;

-

-        case IDM_FILE_PREVIOUS:

-

-            /* read previous entry in the directory */

-

-            if (SearchPngList (pPngFileList, iPngFileCount, &iPngFileIndex,

-                szImgPathName, NULL))

-            {

-

-                if (strcmp (szImgPathName, "") == 0)

-                    return 0;

-

-                /* load the image from file */

-

-                if (!LoadImageFile (hwnd, szImgPathName, &pbImage, &cxImgSize,

-                    &cyImgSize, &cImgChannels, &bkgColor))

-                    return 0;

-

-                /* invalidate the client area for later update */

-

-                InvalidateRect (hwnd, NULL, TRUE);

-

-                /* display the PNG into the DIBitmap */

-

-                DisplayImage (hwnd, &pDib, &pDiData, cxWinSize, cyWinSize,

-                    pbImage, cxImgSize, cyImgSize, cImgChannels, bStretched);

-            }

-

-            return 0;

-

-        case IDM_FILE_EXIT:

-

-            /* more cleanup needed... */

-

-            /* free image buffer */

-

-            if (pDib != NULL)

-            {

-                free (pDib);

-                pDib = NULL;

-            }

-

-            /* free file-list */

-

-            if (pPngFileList != NULL)

-            {

-                free (pPngFileList);

-                pPngFileList = NULL;

-            }

-

-            /* let's go ... */

-

-            exit (0);

-

-            return 0;

-

-        case IDM_OPTIONS_STRETCH:

-            bStretched = !bStretched;

-            if (bStretched)

-                CheckMenuItem (hMenu, IDM_OPTIONS_STRETCH, MF_CHECKED);

-            else

-                CheckMenuItem (hMenu, IDM_OPTIONS_STRETCH, MF_UNCHECKED);

-

-            /* invalidate the client area for later update */

-

-            InvalidateRect (hwnd, NULL, TRUE);

-

-            /* display the PNG into the DIBitmap */

-

-            DisplayImage (hwnd, &pDib, &pDiData, cxWinSize, cyWinSize,

-                pbImage, cxImgSize, cyImgSize, cImgChannels, bStretched);

-

-            return 0;

-

-        case IDM_HELP_ABOUT:

-            DialogBox (hInstance, TEXT ("AboutBox"), hwnd, AboutDlgProc) ;

-            return 0;

-

-        } /* end switch */

-

-        break;

-

-    case WM_PAINT:

-        hdc = BeginPaint (hwnd, &ps);

-

-        if (pDib)

-            SetDIBitsToDevice (hdc, 0, 0, cxWinSize, cyWinSize, 0, 0,

-                0, cyWinSize, pDiData, (BITMAPINFO *) pDib, DIB_RGB_COLORS);

-

-        EndPaint (hwnd, &ps);

-        return 0;

-

-    case WM_DESTROY:

-        if (pbmfh)

-        {

-            free (pbmfh);

-            pbmfh = NULL;

-        }

-

-        PostQuitMessage (0);

-        return 0;

-    }

-

-    return DefWindowProc (hwnd, message, wParam, lParam);

-}

-

-BOOL CALLBACK AboutDlgProc (HWND hDlg, UINT message,

-                            WPARAM wParam, LPARAM lParam)

-{

-     switch (message)

-     {

-     case WM_INITDIALOG :

-          ShowWindow (hDlg, SW_HIDE);

-          CenterAbout (hDlg, GetWindow (hDlg, GW_OWNER));

-          ShowWindow (hDlg, SW_SHOW);

-          return TRUE ;

-

-     case WM_COMMAND :

-          switch (LOWORD (wParam))

-          {

-          case IDOK :

-          case IDCANCEL :

-               EndDialog (hDlg, 0) ;

-               return TRUE ;

-          }

-          break ;

-     }

-     return FALSE ;

-}

-

-/*---------------

- *  CenterAbout

- *---------------

- */

-BOOL CenterAbout (HWND hwndChild, HWND hwndParent)

-{

-   RECT    rChild, rParent, rWorkArea;

-   int     wChild, hChild, wParent, hParent;

-   int     xNew, yNew;

-   BOOL  bResult;

-

-   /* Get the Height and Width of the child window */

-   GetWindowRect (hwndChild, &rChild);

-   wChild = rChild.right - rChild.left;

-   hChild = rChild.bottom - rChild.top;

-

-   /* Get the Height and Width of the parent window */

-   GetWindowRect (hwndParent, &rParent);

-   wParent = rParent.right - rParent.left;

-   hParent = rParent.bottom - rParent.top;

-

-   /* Get the limits of the 'workarea' */

-   bResult = SystemParametersInfo(

-      SPI_GETWORKAREA,  /* system parameter to query or set */

-      sizeof(RECT),

-      &rWorkArea,

-      0);

-   if (!bResult) {

-      rWorkArea.left = rWorkArea.top = 0;

-      rWorkArea.right = GetSystemMetrics(SM_CXSCREEN);

-      rWorkArea.bottom = GetSystemMetrics(SM_CYSCREEN);

-   }

-

-   /* Calculate new X position, then adjust for workarea */

-   xNew = rParent.left + ((wParent - wChild) /2);

-   if (xNew < rWorkArea.left) {

-      xNew = rWorkArea.left;

-   } else if ((xNew+wChild) > rWorkArea.right) {

-      xNew = rWorkArea.right - wChild;

-   }

-

-   /* Calculate new Y position, then adjust for workarea */

-   yNew = rParent.top  + ((hParent - hChild) /2);

-   if (yNew < rWorkArea.top) {

-      yNew = rWorkArea.top;

-   } else if ((yNew+hChild) > rWorkArea.bottom) {

-      yNew = rWorkArea.bottom - hChild;

-   }

-

-   /* Set it, and return */

-   return SetWindowPos (hwndChild, NULL, xNew, yNew, 0, 0, SWP_NOSIZE |

-          SWP_NOZORDER);

-}

-

-/*----------------

- *  BuildPngList

- *----------------

- */

-BOOL BuildPngList (PTSTR pstrPathName, TCHAR **ppFileList, int *pFileCount,

-     int *pFileIndex)

-{

-    static TCHAR              szImgPathName [MAX_PATH];

-    static TCHAR              szImgFileName [MAX_PATH];

-    static TCHAR              szImgFindName [MAX_PATH];

-

-    WIN32_FIND_DATA           finddata;

-    HANDLE                    hFind;

-

-    static TCHAR              szTmp [MAX_PATH];

-    BOOL                      bOk;

-    int                       i, ii;

-    int                       j, jj;

-

-    /* free previous file-list */

-

-    if (*ppFileList != NULL)

-    {

-        free (*ppFileList);

-        *ppFileList = NULL;

-    }

-

-    /* extract foldername, filename and search-name */

-

-    strcpy (szImgPathName, pstrPathName);

-    strcpy (szImgFileName, strrchr (pstrPathName, '\\') + 1);

-

-    strcpy (szImgFindName, szImgPathName);

-    *(strrchr (szImgFindName, '\\') + 1) = '\0';

-    strcat (szImgFindName, "*.png");

-

-    /* first cycle: count number of files in directory for memory allocation */

-

-    *pFileCount = 0;

-

-    hFind = FindFirstFile(szImgFindName, &finddata);

-    bOk = (hFind != (HANDLE) -1);

-

-    while (bOk)

-    {

-        *pFileCount += 1;

-        bOk = FindNextFile(hFind, &finddata);

-    }

-    FindClose(hFind);

-

-    /* allocation memory for file-list */

-

-    *ppFileList = (TCHAR *) malloc (*pFileCount * MAX_PATH);

-

-    /* second cycle: read directory and store filenames in file-list */

-

-    hFind = FindFirstFile(szImgFindName, &finddata);

-    bOk = (hFind != (HANDLE) -1);

-

-    i = 0;

-    ii = 0;

-    while (bOk)

-    {

-        strcpy (*ppFileList + ii, szImgPathName);

-        strcpy (strrchr(*ppFileList + ii, '\\') + 1, finddata.cFileName);

-

-        if (strcmp(pstrPathName, *ppFileList + ii) == 0)

-            *pFileIndex = i;

-

-        ii += MAX_PATH;

-        i++;

-

-        bOk = FindNextFile(hFind, &finddata);

-    }

-    FindClose(hFind);

-

-    /* finally we must sort the file-list */

-

-    for (i = 0; i < *pFileCount - 1; i++)

-    {

-        ii = i * MAX_PATH;

-        for (j = i+1; j < *pFileCount; j++)

-        {

-            jj = j * MAX_PATH;

-            if (strcmp (*ppFileList + ii, *ppFileList + jj) > 0)

-            {

-                strcpy (szTmp, *ppFileList + jj);

-                strcpy (*ppFileList + jj, *ppFileList + ii);

-                strcpy (*ppFileList + ii, szTmp);

-

-                /* check if this was the current image that we moved */

-

-                if (*pFileIndex == i)

-                    *pFileIndex = j;

-                else

-                    if (*pFileIndex == j)

-                        *pFileIndex = i;

-            }

-        }

-    }

-

-    return TRUE;

-}

-

-/*----------------

- *  SearchPngList

- *----------------

- */

-

-BOOL SearchPngList (

-        TCHAR *pFileList, int FileCount, int *pFileIndex,

-        PTSTR pstrPrevName, PTSTR pstrNextName)

-{

-    if (FileCount > 0)

-    {

-        /* get previous entry */

-

-        if (pstrPrevName != NULL)

-        {

-            if (*pFileIndex > 0)

-                *pFileIndex -= 1;

-            else

-                *pFileIndex = FileCount - 1;

-

-            strcpy (pstrPrevName, pFileList + (*pFileIndex * MAX_PATH));

-        }

-

-        /* get next entry */

-

-        if (pstrNextName != NULL)

-        {

-            if (*pFileIndex < FileCount - 1)

-                *pFileIndex += 1;

-            else

-                *pFileIndex = 0;

-

-            strcpy (pstrNextName, pFileList + (*pFileIndex * MAX_PATH));

-        }

-

-        return TRUE;

-    }

-    else

-    {

-        return FALSE;

-    }

-}

-

-/*-----------------

- *  LoadImageFile

- *-----------------

- */

-

-BOOL LoadImageFile (HWND hwnd, PTSTR pstrPathName,

-                png_byte **ppbImage, int *pxImgSize, int *pyImgSize,

-                int *piChannels, png_color *pBkgColor)

-{

-    static TCHAR szTmp [MAX_PATH];

-

-    /* if there's an existing PNG, free the memory */

-

-    if (*ppbImage)

-    {

-        free (*ppbImage);

-        *ppbImage = NULL;

-    }

-

-    /* Load the entire PNG into memory */

-

-    SetCursor (LoadCursor (NULL, IDC_WAIT));

-    ShowCursor (TRUE);

-

-    PngLoadImage (pstrPathName, ppbImage, pxImgSize, pyImgSize, piChannels,

-                  pBkgColor);

-

-    ShowCursor (FALSE);

-    SetCursor (LoadCursor (NULL, IDC_ARROW));

-

-    if (*ppbImage != NULL)

-    {

-        sprintf (szTmp, "VisualPng - %s", strrchr(pstrPathName, '\\') + 1);

-        SetWindowText (hwnd, szTmp);

-    }

-    else

-    {

-        MessageBox (hwnd, TEXT ("Error in loading the PNG image"),

-            szProgName, MB_ICONEXCLAMATION | MB_OK);

-        return FALSE;

-    }

-

-    return TRUE;

-}

-

-/*----------------

- *  DisplayImage

- *----------------

- */

-BOOL DisplayImage (HWND hwnd, BYTE **ppDib,

-        BYTE **ppDiData, int cxWinSize, int cyWinSize,

-        BYTE *pbImage, int cxImgSize, int cyImgSize, int cImgChannels,

-        BOOL bStretched)

-{

-    BYTE                       *pDib = *ppDib;

-    BYTE                       *pDiData = *ppDiData;

-    /* BITMAPFILEHEADER        *pbmfh; */

-    BITMAPINFOHEADER           *pbmih;

-    WORD                        wDIRowBytes;

-    png_color                   bkgBlack = {0, 0, 0};

-    png_color                   bkgGray  = {127, 127, 127};

-    png_color                   bkgWhite = {255, 255, 255};

-

-    /* allocate memory for the Device Independant bitmap */

-

-    wDIRowBytes = (WORD) ((3 * cxWinSize + 3L) >> 2) << 2;

-

-    if (pDib)

-    {

-        free (pDib);

-        pDib = NULL;

-    }

-

-    if (!(pDib = (BYTE *) malloc (sizeof(BITMAPINFOHEADER) +

-        wDIRowBytes * cyWinSize)))

-    {

-        MessageBox (hwnd, TEXT ("Error in displaying the PNG image"),

-            szProgName, MB_ICONEXCLAMATION | MB_OK);

-        *ppDib = pDib = NULL;

-        return FALSE;

-    }

-    *ppDib = pDib;

-    memset (pDib, 0, sizeof(BITMAPINFOHEADER));

-

-    /* initialize the dib-structure */

-

-    pbmih = (BITMAPINFOHEADER *) pDib;

-    pbmih->biSize = sizeof(BITMAPINFOHEADER);

-    pbmih->biWidth = cxWinSize;

-    pbmih->biHeight = -((long) cyWinSize);

-    pbmih->biPlanes = 1;

-    pbmih->biBitCount = 24;

-    pbmih->biCompression = 0;

-    pDiData = pDib + sizeof(BITMAPINFOHEADER);

-    *ppDiData = pDiData;

-

-    /* first fill bitmap with gray and image border */

-

-    InitBitmap (pDiData, cxWinSize, cyWinSize);

-

-    /* then fill bitmap with image */

-

-    if (pbImage)

-    {

-        FillBitmap (

-            pDiData, cxWinSize, cyWinSize,

-            pbImage, cxImgSize, cyImgSize, cImgChannels,

-            bStretched);

-    }

-

-    return TRUE;

-}

-

-/*--------------

- *  InitBitmap

- *--------------

- */

-BOOL InitBitmap (BYTE *pDiData, int cxWinSize, int cyWinSize)

-{

-    BYTE *dst;

-    int x, y, col;

-

-    /* initialize the background with gray */

-

-    dst = pDiData;

-    for (y = 0; y < cyWinSize; y++)

-    {

-        col = 0;

-        for (x = 0; x < cxWinSize; x++)

-        {

-            /* fill with GRAY */

-            *dst++ = 127;

-            *dst++ = 127;

-            *dst++ = 127;

-            col += 3;

-        }

-        /* rows start on 4 byte boundaries */

-        while ((col % 4) != 0)

-        {

-            dst++;

-            col++;

-        }

-    }

-

-    return TRUE;

-}

-

-/*--------------

- *  FillBitmap

- *--------------

- */

-BOOL FillBitmap (

-        BYTE *pDiData, int cxWinSize, int cyWinSize,

-        BYTE *pbImage, int cxImgSize, int cyImgSize, int cImgChannels,

-        BOOL bStretched)

-{

-    BYTE *pStretchedImage;

-    BYTE *pImg;

-    BYTE *src, *dst;

-    BYTE r, g, b, a;

-    const int cDIChannels = 3;

-    WORD wImgRowBytes;

-    WORD wDIRowBytes;

-    int cxNewSize, cyNewSize;

-    int cxImgPos, cyImgPos;

-    int xImg, yImg;

-    int xWin, yWin;

-    int xOld, yOld;

-    int xNew, yNew;

-

-    if (bStretched)

-    {

-        cxNewSize = cxWinSize - 2 * MARGIN;

-        cyNewSize = cyWinSize - 2 * MARGIN;

-

-        /* stretch the image to it's window determined size */

-

-        /* the following two are mathematically the same, but the first

-         * has side-effects because of rounding

-         */

-/*      if ((cyNewSize / cxNewSize) > (cyImgSize / cxImgSize)) */

-        if ((cyNewSize * cxImgSize) > (cyImgSize * cxNewSize))

-        {

-            cyNewSize = cxNewSize * cyImgSize / cxImgSize;

-            cxImgPos = MARGIN;

-            cyImgPos = (cyWinSize - cyNewSize) / 2;

-        }

-        else

-        {

-            cxNewSize = cyNewSize * cxImgSize / cyImgSize;

-            cyImgPos = MARGIN;

-            cxImgPos = (cxWinSize - cxNewSize) / 2;

-        }

-

-        pStretchedImage = malloc (cImgChannels * cxNewSize * cyNewSize);

-        pImg = pStretchedImage;

-

-        for (yNew = 0; yNew < cyNewSize; yNew++)

-        {

-            yOld = yNew * cyImgSize / cyNewSize;

-            for (xNew = 0; xNew < cxNewSize; xNew++)

-            {

-                xOld = xNew * cxImgSize / cxNewSize;

-

-                r = *(pbImage + cImgChannels * ((yOld * cxImgSize) + xOld) + 0);

-                g = *(pbImage + cImgChannels * ((yOld * cxImgSize) + xOld) + 1);

-                b = *(pbImage + cImgChannels * ((yOld * cxImgSize) + xOld) + 2);

-                *pImg++ = r;

-                *pImg++ = g;

-                *pImg++ = b;

-                if (cImgChannels == 4)

-                {

-                    a = *(pbImage + cImgChannels * ((yOld * cxImgSize) + xOld)

-                        + 3);

-                    *pImg++ = a;

-                }

-            }

-        }

-

-        /* calculate row-bytes */

-

-        wImgRowBytes = cImgChannels * cxNewSize;

-        wDIRowBytes = (WORD) ((cDIChannels * cxWinSize + 3L) >> 2) << 2;

-

-        /* copy image to screen */

-

-        for (yImg = 0, yWin = cyImgPos; yImg < cyNewSize; yImg++, yWin++)

-        {

-            if (yWin >= cyWinSize - cyImgPos)

-                break;

-            src = pStretchedImage + yImg * wImgRowBytes;

-            dst = pDiData + yWin * wDIRowBytes + cxImgPos * cDIChannels;

-

-            for (xImg = 0, xWin = cxImgPos; xImg < cxNewSize; xImg++, xWin++)

-            {

-                if (xWin >= cxWinSize - cxImgPos)

-                    break;

-                r = *src++;

-                g = *src++;

-                b = *src++;

-                *dst++ = b; /* note the reverse order  */

-                *dst++ = g;

-                *dst++ = r;

-                if (cImgChannels == 4)

-                {

-                    a = *src++;

-                }

-            }

-        }

-

-        /* free memory */

-

-        if (pStretchedImage != NULL)

-        {

-            free (pStretchedImage);

-            pStretchedImage = NULL;

-        }

-

-    }

-

-    /* process the image not-stretched */

-

-    else

-    {

-        /* calculate the central position */

-

-        cxImgPos = (cxWinSize - cxImgSize) / 2;

-        cyImgPos = (cyWinSize - cyImgSize) / 2;

-

-        /* check for image larger than window */

-

-        if (cxImgPos < MARGIN)

-            cxImgPos = MARGIN;

-        if (cyImgPos < MARGIN)

-            cyImgPos = MARGIN;

-

-        /* calculate both row-bytes */

-

-        wImgRowBytes = cImgChannels * cxImgSize;

-        wDIRowBytes = (WORD) ((cDIChannels * cxWinSize + 3L) >> 2) << 2;

-

-        /* copy image to screen */

-

-        for (yImg = 0, yWin = cyImgPos; yImg < cyImgSize; yImg++, yWin++)

-        {

-            if (yWin >= cyWinSize - MARGIN)

-                break;

-            src = pbImage + yImg * wImgRowBytes;

-            dst = pDiData + yWin * wDIRowBytes + cxImgPos * cDIChannels;

-

-            for (xImg = 0, xWin = cxImgPos; xImg < cxImgSize; xImg++, xWin++)

-            {

-                if (xWin >= cxWinSize - MARGIN)

-                    break;

-                r = *src++;

-                g = *src++;

-                b = *src++;

-                *dst++ = b; /* note the reverse order  */

-                *dst++ = g;

-                *dst++ = r;

-                if (cImgChannels == 4)

-                {

-                    a = *src++;

-                }

-            }

-        }

-    }

-

-    return TRUE;

-}

-

-/*-----------------

- *  end of source

- *-----------------

- */

+/*------------------------------------
+ *  VisualPng.C -- Shows a PNG image
+ *------------------------------------
+ *
+ * Copyright 2000, Willem van Schaik.
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ */
+
+/* switches */
+
+/* defines */
+
+#define PROGNAME  "VisualPng"
+#define LONGNAME  "Win32 Viewer for PNG-files"
+#define VERSION   "1.0 of 2000 June 07"
+
+/* constants */
+
+#define MARGIN 8
+
+/* standard includes */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <windows.h>
+
+/* application includes */
+
+#include "png.h"
+#include "pngfile.h"
+#include "resource.h"
+
+/* macros */
+
+/* function prototypes */
+
+LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM);
+BOOL    CALLBACK AboutDlgProc (HWND, UINT, WPARAM, LPARAM) ;
+
+BOOL CenterAbout (HWND hwndChild, HWND hwndParent);
+
+BOOL BuildPngList (PTSTR pstrPathName, TCHAR **ppFileList, int *pFileCount,
+        int *pFileIndex);
+
+BOOL SearchPngList (TCHAR *pFileList, int FileCount, int *pFileIndex,
+        PTSTR pstrPrevName, PTSTR pstrNextName);
+
+BOOL LoadImageFile(HWND hwnd, PTSTR pstrPathName,
+        png_byte **ppbImage, int *pxImgSize, int *pyImgSize, int *piChannels,
+        png_color *pBkgColor);
+
+BOOL DisplayImage (HWND hwnd, BYTE **ppDib,
+        BYTE **ppDiData, int cxWinSize, int cyWinSize,
+        BYTE *pbImage, int cxImgSize, int cyImgSize, int cImgChannels,
+        BOOL bStretched);
+
+BOOL InitBitmap (
+        BYTE *pDiData, int cxWinSize, int cyWinSize);
+
+BOOL FillBitmap (
+        BYTE *pDiData, int cxWinSize, int cyWinSize,
+        BYTE *pbImage, int cxImgSize, int cyImgSize, int cImgChannels,
+        BOOL bStretched);
+
+/* a few global variables */
+
+static char *szProgName = PROGNAME;
+static char *szAppName = LONGNAME;
+static char *szIconName = PROGNAME;
+static char szCmdFileName [MAX_PATH];
+
+/* MAIN routine */
+
+int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,
+                    PSTR szCmdLine, int iCmdShow)
+{
+    HACCEL   hAccel;
+    HWND     hwnd;
+    MSG      msg;
+    WNDCLASS wndclass;
+    int ixBorders, iyBorders;
+
+    wndclass.style         = CS_HREDRAW | CS_VREDRAW;
+    wndclass.lpfnWndProc   = WndProc;
+    wndclass.cbClsExtra    = 0;
+    wndclass.cbWndExtra    = 0;
+    wndclass.hInstance     = hInstance;
+    wndclass.hIcon         = LoadIcon (hInstance, szIconName) ;
+    wndclass.hCursor       = LoadCursor (NULL, IDC_ARROW);
+    wndclass.hbrBackground = NULL; /* (HBRUSH) GetStockObject (GRAY_BRUSH); */
+    wndclass.lpszMenuName  = szProgName;
+    wndclass.lpszClassName = szProgName;
+
+    if (!RegisterClass (&wndclass))
+    {
+        MessageBox (NULL, TEXT ("Error: this program requires Windows NT!"),
+            szProgName, MB_ICONERROR);
+        return 0;
+    }
+
+    /* if filename given on commandline, store it */
+    if ((szCmdLine != NULL) && (*szCmdLine != '\0'))
+        if (szCmdLine[0] == '"')
+            strncpy (szCmdFileName, szCmdLine + 1, strlen(szCmdLine) - 2);
+        else
+            strcpy (szCmdFileName, szCmdLine);
+    else
+        strcpy (szCmdFileName, "");
+
+    /* calculate size of window-borders */
+    ixBorders = 2 * (GetSystemMetrics (SM_CXBORDER) +
+                     GetSystemMetrics (SM_CXDLGFRAME));
+    iyBorders = 2 * (GetSystemMetrics (SM_CYBORDER) +
+                     GetSystemMetrics (SM_CYDLGFRAME)) +
+                     GetSystemMetrics (SM_CYCAPTION) +
+                     GetSystemMetrics (SM_CYMENUSIZE) +
+                     1; /* WvS: don't ask me why?  */
+
+    hwnd = CreateWindow (szProgName, szAppName,
+        WS_OVERLAPPEDWINDOW,
+        CW_USEDEFAULT, CW_USEDEFAULT,
+        512 + 2 * MARGIN + ixBorders, 384 + 2 * MARGIN + iyBorders,
+/*      CW_USEDEFAULT, CW_USEDEFAULT, */
+        NULL, NULL, hInstance, NULL);
+
+    ShowWindow (hwnd, iCmdShow);
+    UpdateWindow (hwnd);
+
+    hAccel = LoadAccelerators (hInstance, szProgName);
+
+    while (GetMessage (&msg, NULL, 0, 0))
+    {
+        if (!TranslateAccelerator (hwnd, hAccel, &msg))
+        {
+            TranslateMessage (&msg);
+            DispatchMessage (&msg);
+        }
+    }
+    return msg.wParam;
+}
+
+LRESULT CALLBACK WndProc (HWND hwnd, UINT message, WPARAM wParam,
+        LPARAM lParam)
+{
+    static HINSTANCE          hInstance ;
+    static HDC                hdc;
+    static PAINTSTRUCT        ps;
+    static HMENU              hMenu;
+
+    static BITMAPFILEHEADER  *pbmfh;
+    static BITMAPINFOHEADER  *pbmih;
+    static BYTE              *pbImage;
+    static int                cxWinSize, cyWinSize;
+    static int                cxImgSize, cyImgSize;
+    static int                cImgChannels;
+    static png_color          bkgColor = {127, 127, 127};
+
+    static BOOL               bStretched = TRUE;
+
+    static BYTE              *pDib = NULL;
+    static BYTE              *pDiData = NULL;
+
+    static TCHAR              szImgPathName [MAX_PATH];
+    static TCHAR              szTitleName [MAX_PATH];
+
+    static TCHAR             *pPngFileList = NULL;
+    static int                iPngFileCount;
+    static int                iPngFileIndex;
+
+    BOOL                      bOk;
+
+    switch (message)
+    {
+    case WM_CREATE:
+        hInstance = ((LPCREATESTRUCT) lParam)->hInstance ;
+        PngFileInitialize (hwnd);
+
+        strcpy (szImgPathName, "");
+
+        /* in case we process file given on command-line */
+
+        if (szCmdFileName[0] != '\0')
+        {
+            strcpy (szImgPathName, szCmdFileName);
+
+            /* read the other png-files in the directory for later */
+            /* next/previous commands */
+
+            BuildPngList (szImgPathName, &pPngFileList, &iPngFileCount,
+                          &iPngFileIndex);
+
+            /* load the image from file */
+
+            if (!LoadImageFile (hwnd, szImgPathName,
+                &pbImage, &cxImgSize, &cyImgSize, &cImgChannels, &bkgColor))
+                return 0;
+
+            /* invalidate the client area for later update */
+
+            InvalidateRect (hwnd, NULL, TRUE);
+
+            /* display the PNG into the DIBitmap */
+
+            DisplayImage (hwnd, &pDib, &pDiData, cxWinSize, cyWinSize,
+                pbImage, cxImgSize, cyImgSize, cImgChannels, bStretched);
+        }
+
+        return 0;
+
+    case WM_SIZE:
+        cxWinSize = LOWORD (lParam);
+        cyWinSize = HIWORD (lParam);
+
+        /* invalidate the client area for later update */
+
+        InvalidateRect (hwnd, NULL, TRUE);
+
+        /* display the PNG into the DIBitmap */
+
+        DisplayImage (hwnd, &pDib, &pDiData, cxWinSize, cyWinSize,
+            pbImage, cxImgSize, cyImgSize, cImgChannels, bStretched);
+
+        return 0;
+
+    case WM_INITMENUPOPUP:
+        hMenu = GetMenu (hwnd);
+
+        if (pbImage)
+            EnableMenuItem (hMenu, IDM_FILE_SAVE, MF_ENABLED);
+        else
+            EnableMenuItem (hMenu, IDM_FILE_SAVE, MF_GRAYED);
+
+        return 0;
+
+    case WM_COMMAND:
+        hMenu = GetMenu (hwnd);
+
+        switch (LOWORD (wParam))
+        {
+        case IDM_FILE_OPEN:
+
+            /* show the File Open dialog box */
+
+            if (!PngFileOpenDlg (hwnd, szImgPathName, szTitleName))
+                return 0;
+
+            /* read the other png-files in the directory for later */
+            /* next/previous commands */
+
+            BuildPngList (szImgPathName, &pPngFileList, &iPngFileCount,
+                          &iPngFileIndex);
+
+            /* load the image from file */
+
+            if (!LoadImageFile (hwnd, szImgPathName,
+                &pbImage, &cxImgSize, &cyImgSize, &cImgChannels, &bkgColor))
+                return 0;
+
+            /* invalidate the client area for later update */
+
+            InvalidateRect (hwnd, NULL, TRUE);
+
+            /* display the PNG into the DIBitmap */
+
+            DisplayImage (hwnd, &pDib, &pDiData, cxWinSize, cyWinSize,
+                pbImage, cxImgSize, cyImgSize, cImgChannels, bStretched);
+
+            return 0;
+
+        case IDM_FILE_SAVE:
+
+            /* show the File Save dialog box */
+
+            if (!PngFileSaveDlg (hwnd, szImgPathName, szTitleName))
+                return 0;
+
+            /* save the PNG to a disk file */
+
+            SetCursor (LoadCursor (NULL, IDC_WAIT));
+            ShowCursor (TRUE);
+
+            bOk = PngSaveImage (szImgPathName, pDiData, cxWinSize, cyWinSize,
+                  bkgColor);
+
+            ShowCursor (FALSE);
+            SetCursor (LoadCursor (NULL, IDC_ARROW));
+
+            if (!bOk)
+                MessageBox (hwnd, TEXT ("Error in saving the PNG image"),
+                szProgName, MB_ICONEXCLAMATION | MB_OK);
+            return 0;
+
+        case IDM_FILE_NEXT:
+
+            /* read next entry in the directory */
+
+            if (SearchPngList (pPngFileList, iPngFileCount, &iPngFileIndex,
+                NULL, szImgPathName))
+            {
+                if (strcmp (szImgPathName, "") == 0)
+                    return 0;
+
+                /* load the image from file */
+
+                if (!LoadImageFile (hwnd, szImgPathName, &pbImage,
+                        &cxImgSize, &cyImgSize, &cImgChannels, &bkgColor))
+                    return 0;
+
+                /* invalidate the client area for later update */
+
+                InvalidateRect (hwnd, NULL, TRUE);
+
+                /* display the PNG into the DIBitmap */
+
+                DisplayImage (hwnd, &pDib, &pDiData, cxWinSize, cyWinSize,
+                    pbImage, cxImgSize, cyImgSize, cImgChannels, bStretched);
+            }
+
+            return 0;
+
+        case IDM_FILE_PREVIOUS:
+
+            /* read previous entry in the directory */
+
+            if (SearchPngList (pPngFileList, iPngFileCount, &iPngFileIndex,
+                szImgPathName, NULL))
+            {
+
+                if (strcmp (szImgPathName, "") == 0)
+                    return 0;
+
+                /* load the image from file */
+
+                if (!LoadImageFile (hwnd, szImgPathName, &pbImage, &cxImgSize,
+                    &cyImgSize, &cImgChannels, &bkgColor))
+                    return 0;
+
+                /* invalidate the client area for later update */
+
+                InvalidateRect (hwnd, NULL, TRUE);
+
+                /* display the PNG into the DIBitmap */
+
+                DisplayImage (hwnd, &pDib, &pDiData, cxWinSize, cyWinSize,
+                    pbImage, cxImgSize, cyImgSize, cImgChannels, bStretched);
+            }
+
+            return 0;
+
+        case IDM_FILE_EXIT:
+
+            /* more cleanup needed... */
+
+            /* free image buffer */
+
+            if (pDib != NULL)
+            {
+                free (pDib);
+                pDib = NULL;
+            }
+
+            /* free file-list */
+
+            if (pPngFileList != NULL)
+            {
+                free (pPngFileList);
+                pPngFileList = NULL;
+            }
+
+            /* let's go ... */
+
+            exit (0);
+
+            return 0;
+
+        case IDM_OPTIONS_STRETCH:
+            bStretched = !bStretched;
+            if (bStretched)
+                CheckMenuItem (hMenu, IDM_OPTIONS_STRETCH, MF_CHECKED);
+            else
+                CheckMenuItem (hMenu, IDM_OPTIONS_STRETCH, MF_UNCHECKED);
+
+            /* invalidate the client area for later update */
+
+            InvalidateRect (hwnd, NULL, TRUE);
+
+            /* display the PNG into the DIBitmap */
+
+            DisplayImage (hwnd, &pDib, &pDiData, cxWinSize, cyWinSize,
+                pbImage, cxImgSize, cyImgSize, cImgChannels, bStretched);
+
+            return 0;
+
+        case IDM_HELP_ABOUT:
+            DialogBox (hInstance, TEXT ("AboutBox"), hwnd, AboutDlgProc) ;
+            return 0;
+
+        } /* end switch */
+
+        break;
+
+    case WM_PAINT:
+        hdc = BeginPaint (hwnd, &ps);
+
+        if (pDib)
+            SetDIBitsToDevice (hdc, 0, 0, cxWinSize, cyWinSize, 0, 0,
+                0, cyWinSize, pDiData, (BITMAPINFO *) pDib, DIB_RGB_COLORS);
+
+        EndPaint (hwnd, &ps);
+        return 0;
+
+    case WM_DESTROY:
+        if (pbmfh)
+        {
+            free (pbmfh);
+            pbmfh = NULL;
+        }
+
+        PostQuitMessage (0);
+        return 0;
+    }
+
+    return DefWindowProc (hwnd, message, wParam, lParam);
+}
+
+BOOL CALLBACK AboutDlgProc (HWND hDlg, UINT message,
+                            WPARAM wParam, LPARAM lParam)
+{
+     switch (message)
+     {
+     case WM_INITDIALOG :
+          ShowWindow (hDlg, SW_HIDE);
+          CenterAbout (hDlg, GetWindow (hDlg, GW_OWNER));
+          ShowWindow (hDlg, SW_SHOW);
+          return TRUE ;
+
+     case WM_COMMAND :
+          switch (LOWORD (wParam))
+          {
+          case IDOK :
+          case IDCANCEL :
+               EndDialog (hDlg, 0) ;
+               return TRUE ;
+          }
+          break ;
+     }
+     return FALSE ;
+}
+
+/*---------------
+ *  CenterAbout
+ *---------------
+ */
+BOOL CenterAbout (HWND hwndChild, HWND hwndParent)
+{
+   RECT    rChild, rParent, rWorkArea;
+   int     wChild, hChild, wParent, hParent;
+   int     xNew, yNew;
+   BOOL  bResult;
+
+   /* Get the Height and Width of the child window */
+   GetWindowRect (hwndChild, &rChild);
+   wChild = rChild.right - rChild.left;
+   hChild = rChild.bottom - rChild.top;
+
+   /* Get the Height and Width of the parent window */
+   GetWindowRect (hwndParent, &rParent);
+   wParent = rParent.right - rParent.left;
+   hParent = rParent.bottom - rParent.top;
+
+   /* Get the limits of the 'workarea' */
+   bResult = SystemParametersInfo(
+      SPI_GETWORKAREA,  /* system parameter to query or set */
+      sizeof(RECT),
+      &rWorkArea,
+      0);
+   if (!bResult) {
+      rWorkArea.left = rWorkArea.top = 0;
+      rWorkArea.right = GetSystemMetrics(SM_CXSCREEN);
+      rWorkArea.bottom = GetSystemMetrics(SM_CYSCREEN);
+   }
+
+   /* Calculate new X position, then adjust for workarea */
+   xNew = rParent.left + ((wParent - wChild) /2);
+   if (xNew < rWorkArea.left) {
+      xNew = rWorkArea.left;
+   } else if ((xNew+wChild) > rWorkArea.right) {
+      xNew = rWorkArea.right - wChild;
+   }
+
+   /* Calculate new Y position, then adjust for workarea */
+   yNew = rParent.top  + ((hParent - hChild) /2);
+   if (yNew < rWorkArea.top) {
+      yNew = rWorkArea.top;
+   } else if ((yNew+hChild) > rWorkArea.bottom) {
+      yNew = rWorkArea.bottom - hChild;
+   }
+
+   /* Set it, and return */
+   return SetWindowPos (hwndChild, NULL, xNew, yNew, 0, 0, SWP_NOSIZE |
+          SWP_NOZORDER);
+}
+
+/*----------------
+ *  BuildPngList
+ *----------------
+ */
+BOOL BuildPngList (PTSTR pstrPathName, TCHAR **ppFileList, int *pFileCount,
+     int *pFileIndex)
+{
+    static TCHAR              szImgPathName [MAX_PATH];
+    static TCHAR              szImgFileName [MAX_PATH];
+    static TCHAR              szImgFindName [MAX_PATH];
+
+    WIN32_FIND_DATA           finddata;
+    HANDLE                    hFind;
+
+    static TCHAR              szTmp [MAX_PATH];
+    BOOL                      bOk;
+    int                       i, ii;
+    int                       j, jj;
+
+    /* free previous file-list */
+
+    if (*ppFileList != NULL)
+    {
+        free (*ppFileList);
+        *ppFileList = NULL;
+    }
+
+    /* extract foldername, filename and search-name */
+
+    strcpy (szImgPathName, pstrPathName);
+    strcpy (szImgFileName, strrchr (pstrPathName, '\\') + 1);
+
+    strcpy (szImgFindName, szImgPathName);
+    *(strrchr (szImgFindName, '\\') + 1) = '\0';
+    strcat (szImgFindName, "*.png");
+
+    /* first cycle: count number of files in directory for memory allocation */
+
+    *pFileCount = 0;
+
+    hFind = FindFirstFile(szImgFindName, &finddata);
+    bOk = (hFind != (HANDLE) -1);
+
+    while (bOk)
+    {
+        *pFileCount += 1;
+        bOk = FindNextFile(hFind, &finddata);
+    }
+    FindClose(hFind);
+
+    /* allocation memory for file-list */
+
+    *ppFileList = (TCHAR *) malloc (*pFileCount * MAX_PATH);
+
+    /* second cycle: read directory and store filenames in file-list */
+
+    hFind = FindFirstFile(szImgFindName, &finddata);
+    bOk = (hFind != (HANDLE) -1);
+
+    i = 0;
+    ii = 0;
+    while (bOk)
+    {
+        strcpy (*ppFileList + ii, szImgPathName);
+        strcpy (strrchr(*ppFileList + ii, '\\') + 1, finddata.cFileName);
+
+        if (strcmp(pstrPathName, *ppFileList + ii) == 0)
+            *pFileIndex = i;
+
+        ii += MAX_PATH;
+        i++;
+
+        bOk = FindNextFile(hFind, &finddata);
+    }
+    FindClose(hFind);
+
+    /* finally we must sort the file-list */
+
+    for (i = 0; i < *pFileCount - 1; i++)
+    {
+        ii = i * MAX_PATH;
+        for (j = i+1; j < *pFileCount; j++)
+        {
+            jj = j * MAX_PATH;
+            if (strcmp (*ppFileList + ii, *ppFileList + jj) > 0)
+            {
+                strcpy (szTmp, *ppFileList + jj);
+                strcpy (*ppFileList + jj, *ppFileList + ii);
+                strcpy (*ppFileList + ii, szTmp);
+
+                /* check if this was the current image that we moved */
+
+                if (*pFileIndex == i)
+                    *pFileIndex = j;
+                else
+                    if (*pFileIndex == j)
+                        *pFileIndex = i;
+            }
+        }
+    }
+
+    return TRUE;
+}
+
+/*----------------
+ *  SearchPngList
+ *----------------
+ */
+
+BOOL SearchPngList (
+        TCHAR *pFileList, int FileCount, int *pFileIndex,
+        PTSTR pstrPrevName, PTSTR pstrNextName)
+{
+    if (FileCount > 0)
+    {
+        /* get previous entry */
+
+        if (pstrPrevName != NULL)
+        {
+            if (*pFileIndex > 0)
+                *pFileIndex -= 1;
+            else
+                *pFileIndex = FileCount - 1;
+
+            strcpy (pstrPrevName, pFileList + (*pFileIndex * MAX_PATH));
+        }
+
+        /* get next entry */
+
+        if (pstrNextName != NULL)
+        {
+            if (*pFileIndex < FileCount - 1)
+                *pFileIndex += 1;
+            else
+                *pFileIndex = 0;
+
+            strcpy (pstrNextName, pFileList + (*pFileIndex * MAX_PATH));
+        }
+
+        return TRUE;
+    }
+    else
+    {
+        return FALSE;
+    }
+}
+
+/*-----------------
+ *  LoadImageFile
+ *-----------------
+ */
+
+BOOL LoadImageFile (HWND hwnd, PTSTR pstrPathName,
+                png_byte **ppbImage, int *pxImgSize, int *pyImgSize,
+                int *piChannels, png_color *pBkgColor)
+{
+    static TCHAR szTmp [MAX_PATH];
+
+    /* if there's an existing PNG, free the memory */
+
+    if (*ppbImage)
+    {
+        free (*ppbImage);
+        *ppbImage = NULL;
+    }
+
+    /* Load the entire PNG into memory */
+
+    SetCursor (LoadCursor (NULL, IDC_WAIT));
+    ShowCursor (TRUE);
+
+    PngLoadImage (pstrPathName, ppbImage, pxImgSize, pyImgSize, piChannels,
+                  pBkgColor);
+
+    ShowCursor (FALSE);
+    SetCursor (LoadCursor (NULL, IDC_ARROW));
+
+    if (*ppbImage != NULL)
+    {
+        sprintf (szTmp, "VisualPng - %s", strrchr(pstrPathName, '\\') + 1);
+        SetWindowText (hwnd, szTmp);
+    }
+    else
+    {
+        MessageBox (hwnd, TEXT ("Error in loading the PNG image"),
+            szProgName, MB_ICONEXCLAMATION | MB_OK);
+        return FALSE;
+    }
+
+    return TRUE;
+}
+
+/*----------------
+ *  DisplayImage
+ *----------------
+ */
+BOOL DisplayImage (HWND hwnd, BYTE **ppDib,
+        BYTE **ppDiData, int cxWinSize, int cyWinSize,
+        BYTE *pbImage, int cxImgSize, int cyImgSize, int cImgChannels,
+        BOOL bStretched)
+{
+    BYTE                       *pDib = *ppDib;
+    BYTE                       *pDiData = *ppDiData;
+    /* BITMAPFILEHEADER        *pbmfh; */
+    BITMAPINFOHEADER           *pbmih;
+    WORD                        wDIRowBytes;
+    png_color                   bkgBlack = {0, 0, 0};
+    png_color                   bkgGray  = {127, 127, 127};
+    png_color                   bkgWhite = {255, 255, 255};
+
+    /* allocate memory for the Device Independant bitmap */
+
+    wDIRowBytes = (WORD) ((3 * cxWinSize + 3L) >> 2) << 2;
+
+    if (pDib)
+    {
+        free (pDib);
+        pDib = NULL;
+    }
+
+    if (!(pDib = (BYTE *) malloc (sizeof(BITMAPINFOHEADER) +
+        wDIRowBytes * cyWinSize)))
+    {
+        MessageBox (hwnd, TEXT ("Error in displaying the PNG image"),
+            szProgName, MB_ICONEXCLAMATION | MB_OK);
+        *ppDib = pDib = NULL;
+        return FALSE;
+    }
+    *ppDib = pDib;
+    memset (pDib, 0, sizeof(BITMAPINFOHEADER));
+
+    /* initialize the dib-structure */
+
+    pbmih = (BITMAPINFOHEADER *) pDib;
+    pbmih->biSize = sizeof(BITMAPINFOHEADER);
+    pbmih->biWidth = cxWinSize;
+    pbmih->biHeight = -((long) cyWinSize);
+    pbmih->biPlanes = 1;
+    pbmih->biBitCount = 24;
+    pbmih->biCompression = 0;
+    pDiData = pDib + sizeof(BITMAPINFOHEADER);
+    *ppDiData = pDiData;
+
+    /* first fill bitmap with gray and image border */
+
+    InitBitmap (pDiData, cxWinSize, cyWinSize);
+
+    /* then fill bitmap with image */
+
+    if (pbImage)
+    {
+        FillBitmap (
+            pDiData, cxWinSize, cyWinSize,
+            pbImage, cxImgSize, cyImgSize, cImgChannels,
+            bStretched);
+    }
+
+    return TRUE;
+}
+
+/*--------------
+ *  InitBitmap
+ *--------------
+ */
+BOOL InitBitmap (BYTE *pDiData, int cxWinSize, int cyWinSize)
+{
+    BYTE *dst;
+    int x, y, col;
+
+    /* initialize the background with gray */
+
+    dst = pDiData;
+    for (y = 0; y < cyWinSize; y++)
+    {
+        col = 0;
+        for (x = 0; x < cxWinSize; x++)
+        {
+            /* fill with GRAY */
+            *dst++ = 127;
+            *dst++ = 127;
+            *dst++ = 127;
+            col += 3;
+        }
+        /* rows start on 4 byte boundaries */
+        while ((col % 4) != 0)
+        {
+            dst++;
+            col++;
+        }
+    }
+
+    return TRUE;
+}
+
+/*--------------
+ *  FillBitmap
+ *--------------
+ */
+BOOL FillBitmap (
+        BYTE *pDiData, int cxWinSize, int cyWinSize,
+        BYTE *pbImage, int cxImgSize, int cyImgSize, int cImgChannels,
+        BOOL bStretched)
+{
+    BYTE *pStretchedImage;
+    BYTE *pImg;
+    BYTE *src, *dst;
+    BYTE r, g, b, a;
+    const int cDIChannels = 3;
+    WORD wImgRowBytes;
+    WORD wDIRowBytes;
+    int cxNewSize, cyNewSize;
+    int cxImgPos, cyImgPos;
+    int xImg, yImg;
+    int xWin, yWin;
+    int xOld, yOld;
+    int xNew, yNew;
+
+    if (bStretched)
+    {
+        cxNewSize = cxWinSize - 2 * MARGIN;
+        cyNewSize = cyWinSize - 2 * MARGIN;
+
+        /* stretch the image to it's window determined size */
+
+        /* the following two are mathematically the same, but the first
+         * has side-effects because of rounding
+         */
+/*      if ((cyNewSize / cxNewSize) > (cyImgSize / cxImgSize)) */
+        if ((cyNewSize * cxImgSize) > (cyImgSize * cxNewSize))
+        {
+            cyNewSize = cxNewSize * cyImgSize / cxImgSize;
+            cxImgPos = MARGIN;
+            cyImgPos = (cyWinSize - cyNewSize) / 2;
+        }
+        else
+        {
+            cxNewSize = cyNewSize * cxImgSize / cyImgSize;
+            cyImgPos = MARGIN;
+            cxImgPos = (cxWinSize - cxNewSize) / 2;
+        }
+
+        pStretchedImage = malloc (cImgChannels * cxNewSize * cyNewSize);
+        pImg = pStretchedImage;
+
+        for (yNew = 0; yNew < cyNewSize; yNew++)
+        {
+            yOld = yNew * cyImgSize / cyNewSize;
+            for (xNew = 0; xNew < cxNewSize; xNew++)
+            {
+                xOld = xNew * cxImgSize / cxNewSize;
+
+                r = *(pbImage + cImgChannels * ((yOld * cxImgSize) + xOld) + 0);
+                g = *(pbImage + cImgChannels * ((yOld * cxImgSize) + xOld) + 1);
+                b = *(pbImage + cImgChannels * ((yOld * cxImgSize) + xOld) + 2);
+                *pImg++ = r;
+                *pImg++ = g;
+                *pImg++ = b;
+                if (cImgChannels == 4)
+                {
+                    a = *(pbImage + cImgChannels * ((yOld * cxImgSize) + xOld)
+                        + 3);
+                    *pImg++ = a;
+                }
+            }
+        }
+
+        /* calculate row-bytes */
+
+        wImgRowBytes = cImgChannels * cxNewSize;
+        wDIRowBytes = (WORD) ((cDIChannels * cxWinSize + 3L) >> 2) << 2;
+
+        /* copy image to screen */
+
+        for (yImg = 0, yWin = cyImgPos; yImg < cyNewSize; yImg++, yWin++)
+        {
+            if (yWin >= cyWinSize - cyImgPos)
+                break;
+            src = pStretchedImage + yImg * wImgRowBytes;
+            dst = pDiData + yWin * wDIRowBytes + cxImgPos * cDIChannels;
+
+            for (xImg = 0, xWin = cxImgPos; xImg < cxNewSize; xImg++, xWin++)
+            {
+                if (xWin >= cxWinSize - cxImgPos)
+                    break;
+                r = *src++;
+                g = *src++;
+                b = *src++;
+                *dst++ = b; /* note the reverse order  */
+                *dst++ = g;
+                *dst++ = r;
+                if (cImgChannels == 4)
+                {
+                    a = *src++;
+                }
+            }
+        }
+
+        /* free memory */
+
+        if (pStretchedImage != NULL)
+        {
+            free (pStretchedImage);
+            pStretchedImage = NULL;
+        }
+
+    }
+
+    /* process the image not-stretched */
+
+    else
+    {
+        /* calculate the central position */
+
+        cxImgPos = (cxWinSize - cxImgSize) / 2;
+        cyImgPos = (cyWinSize - cyImgSize) / 2;
+
+        /* check for image larger than window */
+
+        if (cxImgPos < MARGIN)
+            cxImgPos = MARGIN;
+        if (cyImgPos < MARGIN)
+            cyImgPos = MARGIN;
+
+        /* calculate both row-bytes */
+
+        wImgRowBytes = cImgChannels * cxImgSize;
+        wDIRowBytes = (WORD) ((cDIChannels * cxWinSize + 3L) >> 2) << 2;
+
+        /* copy image to screen */
+
+        for (yImg = 0, yWin = cyImgPos; yImg < cyImgSize; yImg++, yWin++)
+        {
+            if (yWin >= cyWinSize - MARGIN)
+                break;
+            src = pbImage + yImg * wImgRowBytes;
+            dst = pDiData + yWin * wDIRowBytes + cxImgPos * cDIChannels;
+
+            for (xImg = 0, xWin = cxImgPos; xImg < cxImgSize; xImg++, xWin++)
+            {
+                if (xWin >= cxWinSize - MARGIN)
+                    break;
+                r = *src++;
+                g = *src++;
+                b = *src++;
+                *dst++ = b; /* note the reverse order  */
+                *dst++ = g;
+                *dst++ = r;
+                if (cImgChannels == 4)
+                {
+                    a = *src++;
+                }
+            }
+        }
+    }
+
+    return TRUE;
+}
+
+/*-----------------
+ *  end of source
+ *-----------------
+ */
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/visupng/VisualPng.rc b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/visupng/VisualPng.rc
index 6e0623a..151c68c 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/visupng/VisualPng.rc
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/visupng/VisualPng.rc
@@ -1,152 +1,152 @@
-//Microsoft Developer Studio generated resource script.

-//

-#include "resource.h"

-

-#define APSTUDIO_READONLY_SYMBOLS

-/////////////////////////////////////////////////////////////////////////////

-//

-// Generated from the TEXTINCLUDE 2 resource.

-//

-#include "afxres.h"

-

-/////////////////////////////////////////////////////////////////////////////

-#undef APSTUDIO_READONLY_SYMBOLS

-

-/////////////////////////////////////////////////////////////////////////////

-// English (U.S.) resources

-

-#if !defined(AFX_RESOURCE_DLL) || defined(AFX_TARG_ENU)

-#ifdef _WIN32

-LANGUAGE LANG_ENGLISH, SUBLANG_ENGLISH_US

-#pragma code_page(1252)

-#endif //_WIN32

-

-#ifdef APSTUDIO_INVOKED

-/////////////////////////////////////////////////////////////////////////////

-//

-// TEXTINCLUDE

-//

-

-1 TEXTINCLUDE DISCARDABLE 

-BEGIN

-    "resource.h\0"

-END

-

-2 TEXTINCLUDE DISCARDABLE 

-BEGIN

-    "#include ""afxres.h""\r\n"

-    "\0"

-END

-

-3 TEXTINCLUDE DISCARDABLE 

-BEGIN

-    "\r\n"

-    "\0"

-END

-

-#endif    // APSTUDIO_INVOKED

-

-

-/////////////////////////////////////////////////////////////////////////////

-//

-// Menu

-//

-

-VISUALPNG MENU DISCARDABLE 

-BEGIN

-    POPUP "&File"

-    BEGIN

-        MENUITEM "&Open Image...\tCtrl+O",      IDM_FILE_OPEN

-        MENUITEM "Save &As...",                 IDM_FILE_SAVE

-        MENUITEM SEPARATOR

-        MENUITEM "&Next Image\tCtrl+N",         IDM_FILE_NEXT

-        MENUITEM "Pre&vious Image\tCtrl+V",     IDM_FILE_PREVIOUS

-        MENUITEM SEPARATOR

-        MENUITEM "E&xit\tAlt+X",                IDM_FILE_EXIT

-    END

-    POPUP "&Options"

-    BEGIN

-        MENUITEM "&Stretch",                    IDM_OPTIONS_STRETCH, CHECKED

-    END

-    POPUP "&Help"

-    BEGIN

-        MENUITEM "&About",                      IDM_HELP_ABOUT

-    END

-END

-

-

-/////////////////////////////////////////////////////////////////////////////

-//

-// Accelerator

-//

-

-VISUALPNG ACCELERATORS DISCARDABLE 

-BEGIN

-    "N",            IDM_FILE_NEXT,          VIRTKEY, CONTROL, NOINVERT

-    "O",            IDM_FILE_OPEN,          VIRTKEY, CONTROL, NOINVERT

-    "P",            IDM_FILE_PREVIOUS,      VIRTKEY, CONTROL, NOINVERT

-    "V",            IDM_FILE_PREVIOUS,      VIRTKEY, CONTROL, NOINVERT

-    "X",            IDM_FILE_EXIT,          VIRTKEY, ALT, NOINVERT

-END

-

-

-/////////////////////////////////////////////////////////////////////////////

-//

-// Icon

-//

-

-// Icon with lowest ID value placed first to ensure application icon

-// remains consistent on all systems.

-VISUALPNG               ICON    DISCARDABLE     "VisualPng.ico"

-

-/////////////////////////////////////////////////////////////////////////////

-//

-// Dialog

-//

-

-ABOUTBOX DIALOG DISCARDABLE  0, 0, 186, 94

-STYLE DS_MODALFRAME | WS_POPUP

-FONT 8, "MS Sans Serif"

-BEGIN

-    DEFPUSHBUTTON   "OK",IDOK,68,67,50,14

-    CTEXT           "VisualPng 1.0  -  June 2000",IDC_STATIC,49,14,88,8

-    LTEXT           "a PNG image viewer",IDC_STATIC,60,30,66,8

-    LTEXT           "(c) Willem van Schaik, 2000",IDC_STATIC,48,52,90,8

-    LTEXT           "to demonstrate the use of libpng in Visual C",

-                    IDC_STATIC,25,38,136,8

-END

-

-

-/////////////////////////////////////////////////////////////////////////////

-//

-// DESIGNINFO

-//

-

-#ifdef APSTUDIO_INVOKED

-GUIDELINES DESIGNINFO DISCARDABLE 

-BEGIN

-    "ABOUTBOX", DIALOG

-    BEGIN

-        LEFTMARGIN, 7

-        RIGHTMARGIN, 179

-        TOPMARGIN, 7

-        BOTTOMMARGIN, 87

-    END

-END

-#endif    // APSTUDIO_INVOKED

-

-#endif    // English (U.S.) resources

-/////////////////////////////////////////////////////////////////////////////

-

-

-

-#ifndef APSTUDIO_INVOKED

-/////////////////////////////////////////////////////////////////////////////

-//

-// Generated from the TEXTINCLUDE 3 resource.

-//

-

-

-/////////////////////////////////////////////////////////////////////////////

-#endif    // not APSTUDIO_INVOKED

-

+//Microsoft Developer Studio generated resource script.
+//
+#include "resource.h"
+
+#define APSTUDIO_READONLY_SYMBOLS
+/////////////////////////////////////////////////////////////////////////////
+//
+// Generated from the TEXTINCLUDE 2 resource.
+//
+#include "afxres.h"
+
+/////////////////////////////////////////////////////////////////////////////
+#undef APSTUDIO_READONLY_SYMBOLS
+
+/////////////////////////////////////////////////////////////////////////////
+// English (U.S.) resources
+
+#if !defined(AFX_RESOURCE_DLL) || defined(AFX_TARG_ENU)
+#ifdef _WIN32
+LANGUAGE LANG_ENGLISH, SUBLANG_ENGLISH_US
+#pragma code_page(1252)
+#endif //_WIN32
+
+#ifdef APSTUDIO_INVOKED
+/////////////////////////////////////////////////////////////////////////////
+//
+// TEXTINCLUDE
+//
+
+1 TEXTINCLUDE DISCARDABLE 
+BEGIN
+    "resource.h\0"
+END
+
+2 TEXTINCLUDE DISCARDABLE 
+BEGIN
+    "#include ""afxres.h""\r\n"
+    "\0"
+END
+
+3 TEXTINCLUDE DISCARDABLE 
+BEGIN
+    "\r\n"
+    "\0"
+END
+
+#endif    // APSTUDIO_INVOKED
+
+
+/////////////////////////////////////////////////////////////////////////////
+//
+// Menu
+//
+
+VISUALPNG MENU DISCARDABLE 
+BEGIN
+    POPUP "&File"
+    BEGIN
+        MENUITEM "&Open Image...\tCtrl+O",      IDM_FILE_OPEN
+        MENUITEM "Save &As...",                 IDM_FILE_SAVE
+        MENUITEM SEPARATOR
+        MENUITEM "&Next Image\tCtrl+N",         IDM_FILE_NEXT
+        MENUITEM "Pre&vious Image\tCtrl+V",     IDM_FILE_PREVIOUS
+        MENUITEM SEPARATOR
+        MENUITEM "E&xit\tAlt+X",                IDM_FILE_EXIT
+    END
+    POPUP "&Options"
+    BEGIN
+        MENUITEM "&Stretch",                    IDM_OPTIONS_STRETCH, CHECKED
+    END
+    POPUP "&Help"
+    BEGIN
+        MENUITEM "&About",                      IDM_HELP_ABOUT
+    END
+END
+
+
+/////////////////////////////////////////////////////////////////////////////
+//
+// Accelerator
+//
+
+VISUALPNG ACCELERATORS DISCARDABLE 
+BEGIN
+    "N",            IDM_FILE_NEXT,          VIRTKEY, CONTROL, NOINVERT
+    "O",            IDM_FILE_OPEN,          VIRTKEY, CONTROL, NOINVERT
+    "P",            IDM_FILE_PREVIOUS,      VIRTKEY, CONTROL, NOINVERT
+    "V",            IDM_FILE_PREVIOUS,      VIRTKEY, CONTROL, NOINVERT
+    "X",            IDM_FILE_EXIT,          VIRTKEY, ALT, NOINVERT
+END
+
+
+/////////////////////////////////////////////////////////////////////////////
+//
+// Icon
+//
+
+// Icon with lowest ID value placed first to ensure application icon
+// remains consistent on all systems.
+VISUALPNG               ICON    DISCARDABLE     "VisualPng.ico"
+
+/////////////////////////////////////////////////////////////////////////////
+//
+// Dialog
+//
+
+ABOUTBOX DIALOG DISCARDABLE  0, 0, 186, 94
+STYLE DS_MODALFRAME | WS_POPUP
+FONT 8, "MS Sans Serif"
+BEGIN
+    DEFPUSHBUTTON   "OK",IDOK,68,67,50,14
+    CTEXT           "VisualPng 1.0  -  June 2000",IDC_STATIC,49,14,88,8
+    LTEXT           "a PNG image viewer",IDC_STATIC,60,30,66,8
+    LTEXT           "(c) Willem van Schaik, 2000",IDC_STATIC,48,52,90,8
+    LTEXT           "to demonstrate the use of libpng in Visual C",
+                    IDC_STATIC,25,38,136,8
+END
+
+
+/////////////////////////////////////////////////////////////////////////////
+//
+// DESIGNINFO
+//
+
+#ifdef APSTUDIO_INVOKED
+GUIDELINES DESIGNINFO DISCARDABLE 
+BEGIN
+    "ABOUTBOX", DIALOG
+    BEGIN
+        LEFTMARGIN, 7
+        RIGHTMARGIN, 179
+        TOPMARGIN, 7
+        BOTTOMMARGIN, 87
+    END
+END
+#endif    // APSTUDIO_INVOKED
+
+#endif    // English (U.S.) resources
+/////////////////////////////////////////////////////////////////////////////
+
+
+
+#ifndef APSTUDIO_INVOKED
+/////////////////////////////////////////////////////////////////////////////
+//
+// Generated from the TEXTINCLUDE 3 resource.
+//
+
+
+/////////////////////////////////////////////////////////////////////////////
+#endif    // not APSTUDIO_INVOKED
+
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/visupng/cexcept.h b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/visupng/cexcept.h
index 83c8bfe..5f45d76 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/visupng/cexcept.h
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/visupng/cexcept.h
@@ -1,248 +1,248 @@
-/*===

-cexcept.h 2.0.1 (2008-Jul-19-Sat)

-http://www.nicemice.net/cexcept/

-Adam M. Costello

-http://www.nicemice.net/amc/

-

-An interface for exception-handling in ANSI C (C89 and subsequent ISO

-standards), developed jointly with Cosmin Truta.

-

-    Copyright (c) 2000-2008 Adam M. Costello and Cosmin Truta.

-    This software may be modified only if its author and version

-    information is updated accurately, and may be redistributed

-    only if accompanied by this unaltered notice.  Subject to those

-    restrictions, permission is granted to anyone to do anything

-    with this software.  The copyright holders make no guarantees

-    regarding this software, and are not responsible for any damage

-    resulting from its use.

-

-The cexcept interface is not compatible with and cannot interact

-with system exceptions (like division by zero or memory segmentation

-violation), compiler-generated exceptions (like C++ exceptions), or

-other exception-handling interfaces.

-

-When using this interface across multiple .c files, do not include

-this header file directly.  Instead, create a wrapper header file that

-includes this header file and then invokes the define_exception_type

-macro (see below).  The .c files should then include that header file.

-

-The interface consists of one type, one well-known name, and six macros.

-

-

-define_exception_type(type_name);

-

-    This macro is used like an external declaration.  It specifies

-    the type of object that gets copied from the exception thrower to

-    the exception catcher.  The type_name can be any type that can be

-    assigned to, that is, a non-constant arithmetic type, struct, union,

-    or pointer.  Examples:

-

-        define_exception_type(int);

-

-        enum exception { out_of_memory, bad_arguments, disk_full };

-        define_exception_type(enum exception);

-

-        struct exception { int code; const char *msg; };

-        define_exception_type(struct exception);

-

-    Because throwing an exception causes the object to be copied (not

-    just once, but twice), programmers may wish to consider size when

-    choosing the exception type.

-

-

-struct exception_context;

-

-    This type may be used after the define_exception_type() macro has

-    been invoked.  A struct exception_context must be known to both

-    the thrower and the catcher.  It is expected that there be one

-    context for each thread that uses exceptions.  It would certainly

-    be dangerous for multiple threads to access the same context.

-    One thread can use multiple contexts, but that is likely to be

-    confusing and not typically useful.  The application can allocate

-    this structure in any way it pleases--automatic, static, or dynamic.

-    The application programmer should pretend not to know the structure

-    members, which are subject to change.

-

-

-struct exception_context *the_exception_context;

-

-    The Try/Catch and Throw statements (described below) implicitly

-    refer to a context, using the name the_exception_context.  It is

-    the application's responsibility to make sure that this name yields

-    the address of a mutable (non-constant) struct exception_context

-    wherever those statements are used.  Subject to that constraint, the

-    application may declare a variable of this name anywhere it likes

-    (inside a function, in a parameter list, or externally), and may

-    use whatever storage class specifiers (static, extern, etc) or type

-    qualifiers (const, volatile, etc) it likes.  Examples:

-

-        static struct exception_context

-          * const the_exception_context = &foo;

-

-        { struct exception_context *the_exception_context = bar; ... }

-

-        int blah(struct exception_context *the_exception_context, ...);

-

-        extern struct exception_context the_exception_context[1];

-

-    The last example illustrates a trick that avoids creating a pointer

-    object separate from the structure object.

-

-    The name could even be a macro, for example:

-

-        struct exception_context ec_array[numthreads];

-        #define the_exception_context (ec_array + thread_id)

-

-    Be aware that the_exception_context is used several times by the

-    Try/Catch/Throw macros, so it shouldn't be expensive or have side

-    effects.  The expansion must be a drop-in replacement for an

-    identifier, so it's safest to put parentheses around it.

-

-

-void init_exception_context(struct exception_context *ec);

-

-    For context structures allocated statically (by an external

-    definition or using the "static" keyword), the implicit

-    initialization to all zeros is sufficient, but contexts allocated

-    by other means must be initialized using this macro before they

-    are used by a Try/Catch statement.  It does no harm to initialize

-    a context more than once (by using this macro on a statically

-    allocated context, or using this macro twice on the same context),

-    but a context must not be re-initialized after it has been used by a

-    Try/Catch statement.

-

-

-Try statement

-Catch (expression) statement

-

-    The Try/Catch/Throw macros are capitalized in order to avoid

-    confusion with the C++ keywords, which have subtly different

-    semantics.

-

-    A Try/Catch statement has a syntax similar to an if/else statement,

-    except that the parenthesized expression goes after the second

-    keyword rather than the first.  As with if/else, there are two

-    clauses, each of which may be a simple statement ending with a

-    semicolon or a brace-enclosed compound statement.  But whereas

-    the else clause is optional, the Catch clause is required.  The

-    expression must be a modifiable lvalue (something capable of being

-    assigned to) of the same type (disregarding type qualifiers) that

-    was passed to define_exception_type().

-

-    If a Throw that uses the same exception context as the Try/Catch is

-    executed within the Try clause (typically within a function called

-    by the Try clause), and the exception is not caught by a nested

-    Try/Catch statement, then a copy of the exception will be assigned

-    to the expression, and control will jump to the Catch clause.  If no

-    such Throw is executed, then the assignment is not performed, and

-    the Catch clause is not executed.

-

-    The expression is not evaluated unless and until the exception is

-    caught, which is significant if it has side effects, for example:

-

-        Try foo();

-        Catch (p[++i].e) { ... }

-

-    IMPORTANT: Jumping into or out of a Try clause (for example via

-    return, break, continue, goto, longjmp) is forbidden--the compiler

-    will not complain, but bad things will happen at run-time.  Jumping

-    into or out of a Catch clause is okay, and so is jumping around

-    inside a Try clause.  In many cases where one is tempted to return

-    from a Try clause, it will suffice to use Throw, and then return

-    from the Catch clause.  Another option is to set a flag variable and

-    use goto to jump to the end of the Try clause, then check the flag

-    after the Try/Catch statement.

-

-    IMPORTANT: The values of any non-volatile automatic variables

-    changed within the Try clause are undefined after an exception is

-    caught.  Therefore, variables modified inside the Try block whose

-    values are needed later outside the Try block must either use static

-    storage or be declared with the "volatile" type qualifier.

-

-

-Throw expression;

-

-    A Throw statement is very much like a return statement, except that

-    the expression is required.  Whereas return jumps back to the place

-    where the current function was called, Throw jumps back to the Catch

-    clause of the innermost enclosing Try clause.  The expression must

-    be compatible with the type passed to define_exception_type().  The

-    exception must be caught, otherwise the program may crash.

-

-    Slight limitation:  If the expression is a comma-expression, it must

-    be enclosed in parentheses.

-

-

-Try statement

-Catch_anonymous statement

-

-    When the value of the exception is not needed, a Try/Catch statement

-    can use Catch_anonymous instead of Catch (expression).

-

-

-Everything below this point is for the benefit of the compiler.  The

-application programmer should pretend not to know any of it, because it

-is subject to change.

-

-===*/

-

-

-#ifndef CEXCEPT_H

-#define CEXCEPT_H

-

-

-#include <setjmp.h>

-

-#define define_exception_type(etype) \

-struct exception_context { \

-  jmp_buf *penv; \

-  int caught; \

-  volatile struct { etype etmp; } v; \

-}

-

-/* etmp must be volatile because the application might use automatic */

-/* storage for the_exception_context, and etmp is modified between   */

-/* the calls to setjmp() and longjmp().  A wrapper struct is used to */

-/* avoid warnings about a duplicate volatile qualifier in case etype */

-/* already includes it.                                              */

-

-#define init_exception_context(ec) ((void)((ec)->penv = 0))

-

-#define Try \

-  { \

-    jmp_buf *exception__prev, exception__env; \

-    exception__prev = the_exception_context->penv; \

-    the_exception_context->penv = &exception__env; \

-    if (setjmp(exception__env) == 0) { \

-      do

-

-#define exception__catch(action) \

-      while (the_exception_context->caught = 0, \

-             the_exception_context->caught); \

-    } \

-    else { \

-      the_exception_context->caught = 1; \

-    } \

-    the_exception_context->penv = exception__prev; \

-  } \

-  if (!the_exception_context->caught || action) { } \

-  else

-

-#define Catch(e) exception__catch(((e) = the_exception_context->v.etmp, 0))

-#define Catch_anonymous exception__catch(0)

-

-/* Try ends with do, and Catch begins with while(0) and ends with     */

-/* else, to ensure that Try/Catch syntax is similar to if/else        */

-/* syntax.                                                            */

-/*                                                                    */

-/* The 0 in while(0) is expressed as x=0,x in order to appease        */

-/* compilers that warn about constant expressions inside while().     */

-/* Most compilers should still recognize that the condition is always */

-/* false and avoid generating code for it.                            */

-

-#define Throw \

-  for (;; longjmp(*the_exception_context->penv, 1)) \

-    the_exception_context->v.etmp =

-

-

-#endif /* CEXCEPT_H */

+/*===
+cexcept.h 2.0.1 (2008-Jul-19-Sat)
+http://www.nicemice.net/cexcept/
+Adam M. Costello
+http://www.nicemice.net/amc/
+
+An interface for exception-handling in ANSI C (C89 and subsequent ISO
+standards), developed jointly with Cosmin Truta.
+
+    Copyright (c) 2000-2008 Adam M. Costello and Cosmin Truta.
+    This software may be modified only if its author and version
+    information is updated accurately, and may be redistributed
+    only if accompanied by this unaltered notice.  Subject to those
+    restrictions, permission is granted to anyone to do anything
+    with this software.  The copyright holders make no guarantees
+    regarding this software, and are not responsible for any damage
+    resulting from its use.
+
+The cexcept interface is not compatible with and cannot interact
+with system exceptions (like division by zero or memory segmentation
+violation), compiler-generated exceptions (like C++ exceptions), or
+other exception-handling interfaces.
+
+When using this interface across multiple .c files, do not include
+this header file directly.  Instead, create a wrapper header file that
+includes this header file and then invokes the define_exception_type
+macro (see below).  The .c files should then include that header file.
+
+The interface consists of one type, one well-known name, and six macros.
+
+
+define_exception_type(type_name);
+
+    This macro is used like an external declaration.  It specifies
+    the type of object that gets copied from the exception thrower to
+    the exception catcher.  The type_name can be any type that can be
+    assigned to, that is, a non-constant arithmetic type, struct, union,
+    or pointer.  Examples:
+
+        define_exception_type(int);
+
+        enum exception { out_of_memory, bad_arguments, disk_full };
+        define_exception_type(enum exception);
+
+        struct exception { int code; const char *msg; };
+        define_exception_type(struct exception);
+
+    Because throwing an exception causes the object to be copied (not
+    just once, but twice), programmers may wish to consider size when
+    choosing the exception type.
+
+
+struct exception_context;
+
+    This type may be used after the define_exception_type() macro has
+    been invoked.  A struct exception_context must be known to both
+    the thrower and the catcher.  It is expected that there be one
+    context for each thread that uses exceptions.  It would certainly
+    be dangerous for multiple threads to access the same context.
+    One thread can use multiple contexts, but that is likely to be
+    confusing and not typically useful.  The application can allocate
+    this structure in any way it pleases--automatic, static, or dynamic.
+    The application programmer should pretend not to know the structure
+    members, which are subject to change.
+
+
+struct exception_context *the_exception_context;
+
+    The Try/Catch and Throw statements (described below) implicitly
+    refer to a context, using the name the_exception_context.  It is
+    the application's responsibility to make sure that this name yields
+    the address of a mutable (non-constant) struct exception_context
+    wherever those statements are used.  Subject to that constraint, the
+    application may declare a variable of this name anywhere it likes
+    (inside a function, in a parameter list, or externally), and may
+    use whatever storage class specifiers (static, extern, etc) or type
+    qualifiers (const, volatile, etc) it likes.  Examples:
+
+        static struct exception_context
+          * const the_exception_context = &foo;
+
+        { struct exception_context *the_exception_context = bar; ... }
+
+        int blah(struct exception_context *the_exception_context, ...);
+
+        extern struct exception_context the_exception_context[1];
+
+    The last example illustrates a trick that avoids creating a pointer
+    object separate from the structure object.
+
+    The name could even be a macro, for example:
+
+        struct exception_context ec_array[numthreads];
+        #define the_exception_context (ec_array + thread_id)
+
+    Be aware that the_exception_context is used several times by the
+    Try/Catch/Throw macros, so it shouldn't be expensive or have side
+    effects.  The expansion must be a drop-in replacement for an
+    identifier, so it's safest to put parentheses around it.
+
+
+void init_exception_context(struct exception_context *ec);
+
+    For context structures allocated statically (by an external
+    definition or using the "static" keyword), the implicit
+    initialization to all zeros is sufficient, but contexts allocated
+    by other means must be initialized using this macro before they
+    are used by a Try/Catch statement.  It does no harm to initialize
+    a context more than once (by using this macro on a statically
+    allocated context, or using this macro twice on the same context),
+    but a context must not be re-initialized after it has been used by a
+    Try/Catch statement.
+
+
+Try statement
+Catch (expression) statement
+
+    The Try/Catch/Throw macros are capitalized in order to avoid
+    confusion with the C++ keywords, which have subtly different
+    semantics.
+
+    A Try/Catch statement has a syntax similar to an if/else statement,
+    except that the parenthesized expression goes after the second
+    keyword rather than the first.  As with if/else, there are two
+    clauses, each of which may be a simple statement ending with a
+    semicolon or a brace-enclosed compound statement.  But whereas
+    the else clause is optional, the Catch clause is required.  The
+    expression must be a modifiable lvalue (something capable of being
+    assigned to) of the same type (disregarding type qualifiers) that
+    was passed to define_exception_type().
+
+    If a Throw that uses the same exception context as the Try/Catch is
+    executed within the Try clause (typically within a function called
+    by the Try clause), and the exception is not caught by a nested
+    Try/Catch statement, then a copy of the exception will be assigned
+    to the expression, and control will jump to the Catch clause.  If no
+    such Throw is executed, then the assignment is not performed, and
+    the Catch clause is not executed.
+
+    The expression is not evaluated unless and until the exception is
+    caught, which is significant if it has side effects, for example:
+
+        Try foo();
+        Catch (p[++i].e) { ... }
+
+    IMPORTANT: Jumping into or out of a Try clause (for example via
+    return, break, continue, goto, longjmp) is forbidden--the compiler
+    will not complain, but bad things will happen at run-time.  Jumping
+    into or out of a Catch clause is okay, and so is jumping around
+    inside a Try clause.  In many cases where one is tempted to return
+    from a Try clause, it will suffice to use Throw, and then return
+    from the Catch clause.  Another option is to set a flag variable and
+    use goto to jump to the end of the Try clause, then check the flag
+    after the Try/Catch statement.
+
+    IMPORTANT: The values of any non-volatile automatic variables
+    changed within the Try clause are undefined after an exception is
+    caught.  Therefore, variables modified inside the Try block whose
+    values are needed later outside the Try block must either use static
+    storage or be declared with the "volatile" type qualifier.
+
+
+Throw expression;
+
+    A Throw statement is very much like a return statement, except that
+    the expression is required.  Whereas return jumps back to the place
+    where the current function was called, Throw jumps back to the Catch
+    clause of the innermost enclosing Try clause.  The expression must
+    be compatible with the type passed to define_exception_type().  The
+    exception must be caught, otherwise the program may crash.
+
+    Slight limitation:  If the expression is a comma-expression, it must
+    be enclosed in parentheses.
+
+
+Try statement
+Catch_anonymous statement
+
+    When the value of the exception is not needed, a Try/Catch statement
+    can use Catch_anonymous instead of Catch (expression).
+
+
+Everything below this point is for the benefit of the compiler.  The
+application programmer should pretend not to know any of it, because it
+is subject to change.
+
+===*/
+
+
+#ifndef CEXCEPT_H
+#define CEXCEPT_H
+
+
+#include <setjmp.h>
+
+#define define_exception_type(etype) \
+struct exception_context { \
+  jmp_buf *penv; \
+  int caught; \
+  volatile struct { etype etmp; } v; \
+}
+
+/* etmp must be volatile because the application might use automatic */
+/* storage for the_exception_context, and etmp is modified between   */
+/* the calls to setjmp() and longjmp().  A wrapper struct is used to */
+/* avoid warnings about a duplicate volatile qualifier in case etype */
+/* already includes it.                                              */
+
+#define init_exception_context(ec) ((void)((ec)->penv = 0))
+
+#define Try \
+  { \
+    jmp_buf *exception__prev, exception__env; \
+    exception__prev = the_exception_context->penv; \
+    the_exception_context->penv = &exception__env; \
+    if (setjmp(exception__env) == 0) { \
+      do
+
+#define exception__catch(action) \
+      while (the_exception_context->caught = 0, \
+             the_exception_context->caught); \
+    } \
+    else { \
+      the_exception_context->caught = 1; \
+    } \
+    the_exception_context->penv = exception__prev; \
+  } \
+  if (!the_exception_context->caught || action) { } \
+  else
+
+#define Catch(e) exception__catch(((e) = the_exception_context->v.etmp, 0))
+#define Catch_anonymous exception__catch(0)
+
+/* Try ends with do, and Catch begins with while(0) and ends with     */
+/* else, to ensure that Try/Catch syntax is similar to if/else        */
+/* syntax.                                                            */
+/*                                                                    */
+/* The 0 in while(0) is expressed as x=0,x in order to appease        */
+/* compilers that warn about constant expressions inside while().     */
+/* Most compilers should still recognize that the condition is always */
+/* false and avoid generating code for it.                            */
+
+#define Throw \
+  for (;; longjmp(*the_exception_context->penv, 1)) \
+    the_exception_context->v.etmp =
+
+
+#endif /* CEXCEPT_H */
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/visupng/resource.h b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/visupng/resource.h
index a06050a..b62176d 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/visupng/resource.h
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/contrib/visupng/resource.h
@@ -1,23 +1,23 @@
-//{{NO_DEPENDENCIES}}

-// Microsoft Developer Studio generated include file.

-// Used by VisualPng.rc

-//

-#define IDM_FILE_OPEN                   40001

-#define IDM_FILE_SAVE                   40002

-#define IDM_FILE_NEXT                   40003

-#define IDM_FILE_PREVIOUS               40004

-#define IDM_FILE_EXIT                   40005

-#define IDM_OPTIONS_BACKGROUND          40006

-#define IDM_OPTIONS_STRETCH             40007

-#define IDM_HELP_ABOUT                  40008

-

-// Next default values for new objects

-//

-#ifdef APSTUDIO_INVOKED

-#ifndef APSTUDIO_READONLY_SYMBOLS

-#define _APS_NEXT_RESOURCE_VALUE        113

-#define _APS_NEXT_COMMAND_VALUE         40009

-#define _APS_NEXT_CONTROL_VALUE         1001

-#define _APS_NEXT_SYMED_VALUE           101

-#endif

-#endif

+//{{NO_DEPENDENCIES}}
+// Microsoft Developer Studio generated include file.
+// Used by VisualPng.rc
+//
+#define IDM_FILE_OPEN                   40001
+#define IDM_FILE_SAVE                   40002
+#define IDM_FILE_NEXT                   40003
+#define IDM_FILE_PREVIOUS               40004
+#define IDM_FILE_EXIT                   40005
+#define IDM_OPTIONS_BACKGROUND          40006
+#define IDM_OPTIONS_STRETCH             40007
+#define IDM_HELP_ABOUT                  40008
+
+// Next default values for new objects
+//
+#ifdef APSTUDIO_INVOKED
+#ifndef APSTUDIO_READONLY_SYMBOLS
+#define _APS_NEXT_RESOURCE_VALUE        113
+#define _APS_NEXT_COMMAND_VALUE         40009
+#define _APS_NEXT_CONTROL_VALUE         1001
+#define _APS_NEXT_SYMED_VALUE           101
+#endif
+#endif