Second Life viewer sources 1.23.3-RC

1 files changed, 1621 insertions, 0 deletions

diff --git a/linden/indra/llwindow/glh/glh_linear.h b/linden/indra/llwindow/glh/glh_linear.h
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+/*
+    glh - is a platform-indepenedent C++ OpenGL helper library 
+
+
+    Copyright (c) 2000 Cass Everitt
+        Copyright (c) 2000 NVIDIA Corporation
+    All rights reserved.
+
+    Redistribution and use in source and binary forms, with or
+        without modification, are permitted provided that the following
+        conditions are met:
+
+     * Redistributions of source code must retain the above
+           copyright notice, this list of conditions and the following
+           disclaimer.
+
+     * Redistributions in binary form must reproduce the above
+           copyright notice, this list of conditions and the following
+           disclaimer in the documentation and/or other materials
+           provided with the distribution.
+
+     * The names of contributors to this software may not be used
+           to endorse or promote products derived from this software
+           without specific prior written permission. 
+
+       THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+           ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+           LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+           FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+           REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+           INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+           BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+           LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+           CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+           LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+           ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
+           POSSIBILITY OF SUCH DAMAGE. 
+
+
+    Cass Everitt - cass@r3.nu
+*/
+
+/*
+glh_linear.h
+*/
+
+// Author:  Cass W. Everitt
+
+#ifndef GLH_LINEAR_H
+#define GLH_LINEAR_H
+
+#include <memory.h>
+#include <math.h>
+#include <assert.h>
+
+// only supports float for now...
+#define GLH_REAL_IS_FLOAT
+
+#ifdef GLH_REAL_IS_FLOAT
+# define GLH_REAL float
+# define GLH_REAL_NAMESPACE ns_float
+#endif
+
+#define     GLH_QUATERNION_NORMALIZATION_THRESHOLD  64
+
+#define     GLH_RAD_TO_DEG      GLH_REAL(57.2957795130823208767981548141052)
+#define     GLH_DEG_TO_RAD      GLH_REAL(0.0174532925199432957692369076848861)
+#define     GLH_ZERO            GLH_REAL(0.0)
+#define     GLH_ONE             GLH_REAL(1.0)
+#define     GLH_TWO             GLH_REAL(2.0)
+#define     GLH_EPSILON         GLH_REAL(10e-6)
+#define     GLH_PI              GLH_REAL(3.1415926535897932384626433832795)    
+
+#define     equivalent(a,b)     (((a < b + GLH_EPSILON) && (a > b - GLH_EPSILON)) ? true : false)
+
+namespace glh
+{
+
+        inline GLH_REAL to_degrees(GLH_REAL radians) { return radians*GLH_RAD_TO_DEG; }
+        inline GLH_REAL to_radians(GLH_REAL degrees) { return degrees*GLH_DEG_TO_RAD; }
+
+        // forward declarations for friend template functions.
+        template <int N, class T> class vec;
+        
+        // forward declarations for friend template functions.
+        template <int N, class T>
+                bool operator == ( const vec<N,T> & v1, const vec<N,T> & v2 );
+        
+        // forward declarations for friend template functions.
+        template <int N, class T>
+                bool operator != ( const vec<N,T> & v1, const vec<N,T> & v2 );
+
+        template <int N, class T>       
+        class vec
+        {                               
+    public:
+                int size() const { return N; }
+                
+                vec(const T & t = T()) 
+                { for(int i = 0; i < N; i++) v[i] = t; }
+                vec(const T * tp)
+                { for(int i = 0; i < N; i++) v[i] = tp[i]; }
+                
+                const T * get_value() const
+                { return v; }
+                
+                
+                T dot( const vec<N,T> & rhs ) const
+                { 
+                        T r = 0;
+                        for(int i = 0; i < N; i++) r += v[i]*rhs.v[i];
+                        return r;
+                }
+                
+                T length() const
+                {
+                        T r = 0;
+                        for(int i = 0; i < N; i++) r += v[i]*v[i]; 
+                        return T(sqrt(r));
+                }       
+                
+                T square_norm() const
+                {
+                        T r = 0;
+                        for(int i = 0; i < N; i++) r += v[i]*v[i]; 
+                        return r;
+                }       
+                
+                void  negate()
+                { for(int i = 0; i < N; i++) v[i] = -v[i]; }
+                
+                
+                T normalize() 
+                { 
+                        T sum(0);
+                        for(int i = 0; i < N; i++) 
+                sum += v[i]*v[i];
+                        sum = T(sqrt(sum));
+            if (sum > GLH_EPSILON)
+                            for(int i = 0; i < N; i++) 
+                    v[i] /= sum;
+                        return sum;
+                }
+                
+                
+                vec<N,T> & set_value( const T * rhs )
+                { for(int i = 0; i < N; i++) v[i] = rhs[i]; return *this; }
+                
+                T & operator [] ( int i )
+                { return v[i]; }
+                
+                const T & operator [] ( int i ) const
+                { return v[i]; }
+
+                vec<N,T> & operator *= ( T d )
+                { for(int i = 0; i < N; i++) v[i] *= d; return *this;}
+                
+                vec<N,T> & operator *= ( const vec<N,T> & u )
+                { for(int i = 0; i < N; i++) v[i] *= u[i]; return *this;}
+                
+                vec<N,T> & operator /= ( T d )
+                { if(d == 0) return *this; for(int i = 0; i < N; i++) v[i] /= d; return *this;}
+                
+                vec<N,T> & operator += ( const vec<N,T> & u )
+                { for(int i = 0; i < N; i++) v[i] += u.v[i]; return *this;}
+                
+                vec<N,T> & operator -= ( const vec<N,T> & u )
+                { for(int i = 0; i < N; i++) v[i] -= u.v[i]; return *this;}
+                
+                
+                vec<N,T> operator - () const
+                { vec<N,T> rv = v; rv.negate(); return rv; }
+                
+                vec<N,T> operator + ( const vec<N,T> &v) const
+                { vec<N,T> rt(*this); return rt += v; }
+                
+                vec<N,T> operator - ( const vec<N,T> &v) const
+                { vec<N,T> rt(*this); return rt -= v; }
+                
+                vec<N,T> operator * ( T d) const
+                { vec<N,T> rt(*this); return rt *= d; }
+                
+                friend bool operator == <> ( const vec<N,T> &v1, const vec<N,T> &v2 );
+                friend bool operator != <> ( const vec<N,T> &v1, const vec<N,T> &v2 );
+                
+                
+        //protected:
+                T v[N];
+        };
+        
+        
+        
+        // vector friend operators
+        
+        template <int N, class T> inline
+                vec<N,T> operator * ( const vec<N,T> & b, T d )
+        {
+                vec<N,T> rt(b);
+                return rt *= d;
+        }
+
+        template <int N, class T> inline
+                vec<N,T> operator * ( T d, const vec<N,T> & b )
+        { return b*d; }
+        
+        template <int N, class T> inline
+                vec<N,T> operator * ( const vec<N,T> & b, const vec<N,T> & d )
+        {
+                vec<N,T> rt(b);
+                return rt *= d;
+        }
+
+        template <int N, class T> inline
+                vec<N,T> operator / ( const vec<N,T> & b, T d )
+        { vec<N,T> rt(b); return rt /= d; }
+        
+        template <int N, class T> inline
+                vec<N,T> operator + ( const vec<N,T> & v1, const vec<N,T> & v2 )
+        { vec<N,T> rt(v1); return rt += v2; }
+        
+        template <int N, class T> inline
+                vec<N,T> operator - ( const vec<N,T> & v1, const vec<N,T> & v2 )
+        { vec<N,T> rt(v1); return rt -= v2; }
+        
+        
+        template <int N, class T> inline
+                bool operator == ( const vec<N,T> & v1, const vec<N,T> & v2 )
+        {
+                for(int i = 0; i < N; i++)
+                        if(v1.v[i] != v2.v[i])
+                                return false;
+                        return true;
+        }
+        
+        template <int N, class T> inline
+                bool operator != ( const vec<N,T> & v1, const vec<N,T> & v2 )
+        { return !(v1 == v2); }
+        
+
+        typedef vec<3,unsigned char> vec3ub;
+        typedef vec<4,unsigned char> vec4ub;
+
+
+
+
+
+        namespace GLH_REAL_NAMESPACE
+        {
+        typedef GLH_REAL real;
+
+        class line;
+        class plane;
+        class matrix4;
+        class quaternion;
+        typedef quaternion rotation; 
+  
+        class vec2 : public vec<2,real>
+        {
+    public:
+                vec2(const real & t = real()) : vec<2,real>(t)
+                {}
+                vec2(const vec<2,real> & t) : vec<2,real>(t)
+                {}
+                vec2(const real * tp) : vec<2,real>(tp)
+                {}
+                
+                vec2(real x, real y )
+                { v[0] = x; v[1] = y; }
+                
+                void get_value(real & x, real & y) const
+                { x = v[0]; y = v[1]; }
+                
+                vec2 & set_value( const real & x, const real & y)
+                { v[0] = x; v[1] = y; return *this; }
+                
+        };
+        
+        
+        class vec3 : public vec<3,real>
+        {
+    public:
+                vec3(const real & t = real()) : vec<3,real>(t)
+                {}
+                vec3(const vec<3,real> & t) : vec<3,real>(t)
+                {}
+                vec3(const real * tp) : vec<3,real>(tp)
+                {}
+                
+                vec3(real x, real y, real z)
+                { v[0] = x; v[1] = y; v[2] = z; }
+                
+                void get_value(real & x, real & y, real & z) const
+                { x = v[0]; y = v[1]; z = v[2]; }
+                
+                vec3 cross( const vec3 &rhs ) const
+                {
+                        vec3 rt;
+                        rt.v[0] = v[1]*rhs.v[2]-v[2]*rhs.v[1];
+                        rt.v[1] = v[2]*rhs.v[0]-v[0]*rhs.v[2];
+                        rt.v[2] = v[0]*rhs.v[1]-v[1]*rhs.v[0];  
+                        return rt;
+                }
+                
+                vec3 & set_value( const real & x, const real & y, const real & z)
+                { v[0] = x; v[1] = y; v[2] = z; return *this; }
+                
+        };
+
+                
+    class vec4 : public vec<4,real>
+    {
+    public:
+        vec4(const real & t = real()) : vec<4,real>(t)
+        {}
+        vec4(const vec<4,real> & t) : vec<4,real>(t)
+        {}
+
+        vec4(const vec<3,real> & t, real fourth)
+
+        { v[0] = t.v[0]; v[1] = t.v[1]; v[2] = t.v[2]; v[3] = fourth; }
+        vec4(const real * tp) : vec<4,real>(tp)
+        {}
+        vec4(real x, real y, real z, real w)
+        { v[0] = x; v[1] = y; v[2] = z; v[3] = w; }
+
+        void get_value(real & x, real & y, real & z, real & w) const
+        { x = v[0]; y = v[1]; z = v[2]; w = v[3]; }
+  
+        vec4 & set_value( const real & x, const real & y, const real & z, const real & w)
+        { v[0] = x; v[1] = y; v[2] = z; v[3] = w; return *this; }
+    };
+
+    inline
+    vec3 homogenize(const vec4 & v)
+    {
+      vec3 rt;
+      assert(v.v[3] != GLH_ZERO);
+      rt.v[0] = v.v[0]/v.v[3];
+      rt.v[1] = v.v[1]/v.v[3];
+      rt.v[2] = v.v[2]/v.v[3];
+      return rt;
+    }
+  
+
+
+    class line
+    {
+    public:
+  
+        line()
+        { set_value(vec3(0,0,0),vec3(0,0,1)); }
+
+        line( const vec3 & p0, const vec3 &p1)
+        { set_value(p0,p1); }
+
+        void set_value( const vec3 &p0, const vec3 &p1)
+        {
+          position = p0;
+          direction = p1-p0;
+          direction.normalize();
+        }
+  
+        bool get_closest_points(const line &line2, 
+                                                  vec3 &pointOnThis,
+                                                  vec3 &pointOnThat)
+        {
+  
+          // quick check to see if parallel -- if so, quit.
+          if(fabs(direction.dot(line2.direction)) == 1.0)
+                  return 0;
+          line l2 = line2;
+  
+          // Algorithm: Brian Jean
+          // 
+          register real u;
+          register real v;
+          vec3 Vr = direction;
+          vec3 Vs = l2.direction;
+          register real Vr_Dot_Vs = Vr.dot(Vs);
+          register real detA = real(1.0 - (Vr_Dot_Vs * Vr_Dot_Vs));
+          vec3 C = l2.position - position;
+          register real C_Dot_Vr =  C.dot(Vr);
+          register real C_Dot_Vs =  C.dot(Vs);
+  
+          u = (C_Dot_Vr - Vr_Dot_Vs * C_Dot_Vs)/detA;
+          v = (C_Dot_Vr * Vr_Dot_Vs - C_Dot_Vs)/detA;
+  
+          pointOnThis = position;
+          pointOnThis += direction * u;
+          pointOnThat = l2.position;
+          pointOnThat += l2.direction * v;
+  
+          return 1;
+        }
+  
+        vec3 get_closest_point(const vec3 &point)
+        {
+          vec3 np = point - position;
+          vec3 rp = direction*direction.dot(np)+position;
+          return rp;
+        }
+  
+        const vec3 & get_position() const {return position;}
+
+        const vec3 & get_direction() const {return direction;}
+  
+    //protected:
+        vec3 position;
+        vec3 direction;
+    };
+  
+  
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+  
+  
+
+
+
+
+
+
+
+
+
+
+
+  // matrix
+
+  
+  class matrix4
+  {
+    
+  public:
+        
+    matrix4() { make_identity(); }
+    
+        matrix4( real r ) 
+        { set_value(r); }
+
+        matrix4( real * m )
+        { set_value(m); }
+    
+    matrix4( real a00, real a01, real a02, real a03,
+               real a10, real a11, real a12, real a13,
+                   real a20, real a21, real a22, real a23,
+                   real a30, real a31, real a32, real a33 )
+        {
+                element(0,0) = a00;
+                element(0,1) = a01;
+                element(0,2) = a02;
+                element(0,3) = a03;
+                
+                element(1,0) = a10;
+                element(1,1) = a11;
+                element(1,2) = a12;
+                element(1,3) = a13;
+                
+                element(2,0) = a20;
+                element(2,1) = a21;
+                element(2,2) = a22;
+                element(2,3) = a23;
+                
+                element(3,0) = a30;
+                element(3,1) = a31;
+                element(3,2) = a32;
+                element(3,3) = a33;
+        }
+            
+    
+    void get_value( real * mp ) const
+        {
+                int c = 0;
+                for(int j=0; j < 4; j++)
+                        for(int i=0; i < 4; i++)
+                                mp[c++] = element(i,j);
+        }
+    
+    
+    const real * get_value() const
+        { return m; }
+    
+        void set_value( real * mp)
+        {
+                int c = 0;
+                for(int j=0; j < 4; j++)
+                        for(int i=0; i < 4; i++)
+                                element(i,j) = mp[c++];
+        }
+    
+        void set_value( real r ) 
+        {
+                for(int i=0; i < 4; i++)
+                        for(int j=0; j < 4; j++)
+                                element(i,j) = r;
+        }
+    
+    void make_identity()
+        {
+                element(0,0) = 1.0;
+                element(0,1) = 0.0;
+                element(0,2) = 0.0; 
+                element(0,3) = 0.0;
+                
+                element(1,0) = 0.0;
+                element(1,1) = 1.0; 
+                element(1,2) = 0.0;
+                element(1,3) = 0.0;
+                
+                element(2,0) = 0.0;
+                element(2,1) = 0.0;
+                element(2,2) = 1.0;
+                element(2,3) = 0.0;
+                
+                element(3,0) = 0.0; 
+                element(3,1) = 0.0; 
+                element(3,2) = 0.0;
+                element(3,3) = 1.0;
+        }
+        
+        
+    static matrix4 identity()
+        {
+                static matrix4 mident (
+                        1.0, 0.0, 0.0, 0.0,
+                        0.0, 1.0, 0.0, 0.0,
+                        0.0, 0.0, 1.0, 0.0,
+                        0.0, 0.0, 0.0, 1.0  );
+                return mident;
+        }
+    
+        
+    void set_scale( real s )
+        {
+                element(0,0) = s;
+                element(1,1) = s;
+                element(2,2) = s;
+        }
+    
+    void set_scale( const vec3 & s )
+        {
+                element(0,0) = s.v[0];
+                element(1,1) = s.v[1];
+                element(2,2) = s.v[2];
+        }
+    
+    
+    void set_translate( const vec3 & t )
+        {
+                element(0,3) = t.v[0];
+                element(1,3) = t.v[1];
+                element(2,3) = t.v[2];
+        }
+    
+        void set_row(int r, const vec4 & t)
+        {
+                element(r,0) = t.v[0];
+                element(r,1) = t.v[1];
+                element(r,2) = t.v[2];
+                element(r,3) = t.v[3];
+        }
+
+        void set_column(int c, const vec4 & t)
+        {
+                element(0,c) = t.v[0];
+                element(1,c) = t.v[1];
+                element(2,c) = t.v[2];
+                element(3,c) = t.v[3];
+        }
+
+    
+        void get_row(int r, vec4 & t) const
+        {
+                t.v[0] = element(r,0);
+                t.v[1] = element(r,1);
+                t.v[2] = element(r,2);
+                t.v[3] = element(r,3);
+        }
+
+        vec4 get_row(int r) const
+        {
+                vec4 v; get_row(r, v);
+                return v;
+        }
+
+        void get_column(int c, vec4 & t) const
+        {
+                t.v[0] = element(0,c);
+                t.v[1] = element(1,c);
+                t.v[2] = element(2,c);
+                t.v[3] = element(3,c);
+        }
+
+        vec4 get_column(int c) const
+        {
+                vec4 v; get_column(c, v);
+                return v;
+        }
+
+    matrix4 inverse() const
+        {
+                matrix4 minv;
+                
+                real r1[8], r2[8], r3[8], r4[8];
+                real *s[4], *tmprow;
+                
+                s[0] = &r1[0];
+                s[1] = &r2[0];
+                s[2] = &r3[0];
+                s[3] = &r4[0];
+                
+                register int i,j,p,jj;
+                for(i=0;i<4;i++)
+                {
+                        for(j=0;j<4;j++)
+                        {
+                                s[i][j] = element(i,j);
+                                if(i==j) s[i][j+4] = 1.0;
+                                else     s[i][j+4] = 0.0;
+                        }
+                }
+                real scp[4];
+                for(i=0;i<4;i++)
+                {
+                        scp[i] = real(fabs(s[i][0]));
+                        for(j=1;j<4;j++)
+                                if(real(fabs(s[i][j])) > scp[i]) scp[i] = real(fabs(s[i][j]));
+                                if(scp[i] == 0.0) return minv; // singular matrix!
+                }
+                
+                int pivot_to;
+                real scp_max;
+                for(i=0;i<4;i++)
+                {
+                        // select pivot row
+                        pivot_to = i;
+                        scp_max = real(fabs(s[i][i]/scp[i]));
+                        // find out which row should be on top
+                        for(p=i+1;p<4;p++)
+                                if(real(fabs(s[p][i]/scp[p])) > scp_max)
+                                { scp_max = real(fabs(s[p][i]/scp[p])); pivot_to = p; }
+                                // Pivot if necessary
+                                if(pivot_to != i)
+                                {
+                                        tmprow = s[i];
+                                        s[i] = s[pivot_to];
+                                        s[pivot_to] = tmprow;
+                                        real tmpscp;
+                                        tmpscp = scp[i];
+                                        scp[i] = scp[pivot_to];
+                                        scp[pivot_to] = tmpscp;
+                                }
+                                
+                                real mji;
+                                // perform gaussian elimination
+                                for(j=i+1;j<4;j++)
+                                {
+                                        mji = s[j][i]/s[i][i];
+                                        s[j][i] = 0.0;
+                                        for(jj=i+1;jj<8;jj++)
+                                                s[j][jj] -= mji*s[i][jj];
+                                }
+                }
+                if(s[3][3] == 0.0) return minv; // singular matrix!
+                
+                //
+                // Now we have an upper triangular matrix.
+                //
+                //  x x x x | y y y y
+                //  0 x x x | y y y y 
+                //  0 0 x x | y y y y
+                //  0 0 0 x | y y y y
+                //
+                //  we'll back substitute to get the inverse
+                //
+                //  1 0 0 0 | z z z z
+                //  0 1 0 0 | z z z z
+                //  0 0 1 0 | z z z z
+                //  0 0 0 1 | z z z z 
+                //
+                
+                real mij;
+                for(i=3;i>0;i--)
+                {
+                        for(j=i-1;j > -1; j--)
+                        {
+                                mij = s[j][i]/s[i][i];
+                                for(jj=j+1;jj<8;jj++)
+                                        s[j][jj] -= mij*s[i][jj];
+                        }
+                }
+                
+                for(i=0;i<4;i++)
+                        for(j=0;j<4;j++)
+                                minv(i,j) = s[i][j+4] / s[i][i];
+                        
+                        return minv;
+        }
+    
+    
+    matrix4 transpose() const
+        {
+                matrix4 mtrans;
+                
+                for(int i=0;i<4;i++)
+                        for(int j=0;j<4;j++)
+                                mtrans(i,j) = element(j,i);             
+                return mtrans;
+        }
+    
+    matrix4 & mult_right( const matrix4 & b )
+        {
+                matrix4 mt(*this);
+                set_value(real(0));
+
+                for(int i=0; i < 4; i++)
+                        for(int j=0; j < 4; j++)
+                                for(int c=0; c < 4; c++)
+                                        element(i,j) += mt(i,c) * b(c,j);
+                return *this;
+        }    
+
+    matrix4 & mult_left( const matrix4 & b )
+        {
+                matrix4 mt(*this);
+                set_value(real(0));
+
+                for(int i=0; i < 4; i++)
+                        for(int j=0; j < 4; j++)
+                                for(int c=0; c < 4; c++)
+                                        element(i,j) += b(i,c) * mt(c,j);
+                return *this;
+        }
+        
+        // dst = M * src
+    void mult_matrix_vec( const vec3 &src, vec3 &dst ) const
+        {
+                real w = (
+                        src.v[0] * element(3,0) +
+                        src.v[1] * element(3,1) + 
+                        src.v[2] * element(3,2) +
+                        element(3,3)          );
+        
+        assert(w != GLH_ZERO);
+
+        dst.v[0]  = (
+                        src.v[0] * element(0,0) +
+                        src.v[1] * element(0,1) +
+                        src.v[2] * element(0,2) +
+                        element(0,3)          ) / w;
+                dst.v[1]  = (
+                        src.v[0] * element(1,0) +
+                        src.v[1] * element(1,1) +
+                        src.v[2] * element(1,2) +
+                        element(1,3)          ) / w;
+                dst.v[2]  = (
+                        src.v[0] * element(2,0) +
+                        src.v[1] * element(2,1) + 
+                        src.v[2] * element(2,2) +
+                        element(2,3)          ) / w;
+        }
+    
+        void mult_matrix_vec( vec3 & src_and_dst) const
+        { mult_matrix_vec(vec3(src_and_dst), src_and_dst); }
+
+
+    // dst = src * M
+    void mult_vec_matrix( const vec3 &src, vec3 &dst ) const
+        {
+                real w = (
+                        src.v[0] * element(0,3) +
+                        src.v[1] * element(1,3) +
+                        src.v[2] * element(2,3) +
+                        element(3,3)          );
+        
+        assert(w != GLH_ZERO);
+
+                dst.v[0]  = (
+                        src.v[0] * element(0,0) +
+                        src.v[1] * element(1,0) + 
+                        src.v[2] * element(2,0) + 
+                        element(3,0)          ) / w;
+                dst.v[1]  = (
+                        src.v[0] * element(0,1) +
+                        src.v[1] * element(1,1) +
+                        src.v[2] * element(2,1) +
+                        element(3,1)          ) / w;
+                dst.v[2]  = (
+                        src.v[0] * element(0,2) +
+                        src.v[1] * element(1,2) +
+                        src.v[2] * element(2,2) +
+                        element(3,2)          ) / w;
+        }
+        
+
+        void mult_vec_matrix( vec3 & src_and_dst) const
+        { mult_vec_matrix(vec3(src_and_dst), src_and_dst); }
+
+        // dst = M * src
+    void mult_matrix_vec( const vec4 &src, vec4 &dst ) const
+        {
+        dst.v[0]  = (
+                        src.v[0] * element(0,0) +
+                        src.v[1] * element(0,1) +
+                        src.v[2] * element(0,2) +
+                        src.v[3] * element(0,3));
+                dst.v[1]  = (
+                        src.v[0] * element(1,0) +
+                        src.v[1] * element(1,1) +
+                        src.v[2] * element(1,2) +
+                        src.v[3] * element(1,3));
+                dst.v[2]  = (
+                        src.v[0] * element(2,0) +
+                        src.v[1] * element(2,1) + 
+                        src.v[2] * element(2,2) +
+                        src.v[3] * element(2,3));
+                dst.v[3] = (
+                        src.v[0] * element(3,0) +
+                        src.v[1] * element(3,1) + 
+                        src.v[2] * element(3,2) +
+                        src.v[3] * element(3,3));
+        }
+    
+        void mult_matrix_vec( vec4 & src_and_dst) const
+        { mult_matrix_vec(vec4(src_and_dst), src_and_dst); }
+
+
+    // dst = src * M
+    void mult_vec_matrix( const vec4 &src, vec4 &dst ) const
+        {
+                dst.v[0]  = (
+                        src.v[0] * element(0,0) +
+                        src.v[1] * element(1,0) + 
+                        src.v[2] * element(2,0) + 
+                        src.v[3] * element(3,0));
+                dst.v[1]  = (
+                        src.v[0] * element(0,1) +
+                        src.v[1] * element(1,1) +
+                        src.v[2] * element(2,1) +
+                        src.v[3] * element(3,1));
+                dst.v[2]  = (
+                        src.v[0] * element(0,2) +
+                        src.v[1] * element(1,2) +
+                        src.v[2] * element(2,2) +
+                        src.v[3] * element(3,2));
+                dst.v[3] = (
+                        src.v[0] * element(0,3) +
+                        src.v[1] * element(1,3) +
+                        src.v[2] * element(2,3) +
+                        src.v[3] * element(3,3));
+        }
+        
+
+        void mult_vec_matrix( vec4 & src_and_dst) const
+        { mult_vec_matrix(vec4(src_and_dst), src_and_dst); }
+
+    
+    // dst = M * src
+    void mult_matrix_dir( const vec3 &src, vec3 &dst ) const
+        {
+                dst.v[0]  = (
+                        src.v[0] * element(0,0) +
+                        src.v[1] * element(0,1) +
+                        src.v[2] * element(0,2) ) ;
+                dst.v[1]  = ( 
+                        src.v[0] * element(1,0) +
+                        src.v[1] * element(1,1) +
+                        src.v[2] * element(1,2) ) ;
+                dst.v[2]  = ( 
+                        src.v[0] * element(2,0) +
+                        src.v[1] * element(2,1) + 
+                        src.v[2] * element(2,2) ) ;
+        }
+        
+
+        void mult_matrix_dir( vec3 & src_and_dst) const
+        { mult_matrix_dir(vec3(src_and_dst), src_and_dst); }
+
+
+        // dst = src * M
+    void mult_dir_matrix( const vec3 &src, vec3 &dst ) const
+        {
+                dst.v[0]  = ( 
+                        src.v[0] * element(0,0) +
+                        src.v[1] * element(1,0) +
+                        src.v[2] * element(2,0) ) ;
+                dst.v[1]  = ( 
+                        src.v[0] * element(0,1) +
+                        src.v[1] * element(1,1) +
+                        src.v[2] * element(2,1) ) ;
+                dst.v[2]  = (
+                        src.v[0] * element(0,2) +
+                        src.v[1] * element(1,2) + 
+                        src.v[2] * element(2,2) ) ;
+        }
+    
+    
+        void mult_dir_matrix( vec3 & src_and_dst) const
+        { mult_dir_matrix(vec3(src_and_dst), src_and_dst); }
+
+
+    real & operator () (int row, int col)
+    { return element(row,col); }
+
+    const real & operator () (int row, int col) const
+    { return element(row,col); }
+
+        real & element (int row, int col)
+    { return m[row | (col<<2)]; }
+
+    const real & element (int row, int col) const
+    { return m[row | (col<<2)]; }
+
+    matrix4 & operator *= ( const matrix4 & mat )
+        {
+                mult_right( mat );
+                return *this;
+        }
+    
+    matrix4 & operator *= ( const real & r )
+        {
+                for (int i = 0; i < 4; ++i)
+        {
+            element(0,i) *= r;
+            element(1,i) *= r;
+            element(2,i) *= r;
+            element(3,i) *= r;
+        }
+                return *this;
+        }
+
+    matrix4 & operator += ( const matrix4 & mat )
+        {
+                for (int i = 0; i < 4; ++i)
+        {
+            element(0,i) += mat.element(0,i);
+            element(1,i) += mat.element(1,i);
+            element(2,i) += mat.element(2,i);
+            element(3,i) += mat.element(3,i);
+        }
+                return *this;
+        }
+
+    friend matrix4 operator * ( const matrix4 & m1,     const matrix4 & m2 );
+    friend bool operator == ( const matrix4 & m1, const matrix4 & m2 );
+    friend bool operator != ( const matrix4 & m1, const matrix4 & m2 );
+    
+  //protected:
+          real m[16];
+  };
+  
+  inline  
+  matrix4 operator * ( const matrix4 & m1, const matrix4 & m2 )
+  {
+          matrix4 product;
+          
+          product = m1;
+          product.mult_right(m2);
+          
+          return product;
+  }
+  
+  inline
+  bool operator ==( const matrix4 &m1, const matrix4 &m2 )
+  {
+          return ( 
+                  m1(0,0) == m2(0,0) &&
+                  m1(0,1) == m2(0,1) &&
+                  m1(0,2) == m2(0,2) &&
+                  m1(0,3) == m2(0,3) &&
+                  m1(1,0) == m2(1,0) &&
+                  m1(1,1) == m2(1,1) &&
+                  m1(1,2) == m2(1,2) &&
+                  m1(1,3) == m2(1,3) &&
+                  m1(2,0) == m2(2,0) &&
+                  m1(2,1) == m2(2,1) &&
+                  m1(2,2) == m2(2,2) &&
+                  m1(2,3) == m2(2,3) &&
+                  m1(3,0) == m2(3,0) &&
+                  m1(3,1) == m2(3,1) &&
+                  m1(3,2) == m2(3,2) &&
+                  m1(3,3) == m2(3,3) );
+  }
+  
+  inline
+  bool operator != ( const matrix4 & m1, const matrix4 & m2 )
+  { return !( m1 == m2 ); }  
+
+
+
+
+
+
+
+
+
+
+
+
+  
+    class quaternion
+    {
+    public:
+    
+    quaternion()
+    {
+        *this = identity();
+    }
+
+    quaternion( const real v[4] )
+    {
+        set_value( v );
+    }
+
+
+    quaternion( real q0, real q1, real q2, real q3 )
+    {
+        set_value( q0, q1, q2, q3 );
+    }
+
+
+    quaternion( const matrix4 & m )
+    {
+        set_value( m );
+    }
+
+
+    quaternion( const vec3 &axis, real radians )
+    {
+        set_value( axis, radians );
+    }
+
+
+    quaternion( const vec3 &rotateFrom, const vec3 &rotateTo )
+    {
+        set_value( rotateFrom, rotateTo );
+    }
+
+    quaternion( const vec3 & from_look, const vec3 & from_up,
+                      const vec3 & to_look, const vec3& to_up)
+    {
+            set_value(from_look, from_up, to_look, to_up);
+    }
+
+    const real * get_value() const
+    {
+        return  &q[0];
+    }
+
+    void get_value( real &q0, real &q1, real &q2, real &q3 ) const
+    {
+        q0 = q[0];
+        q1 = q[1];
+        q2 = q[2];
+        q3 = q[3];
+    }
+
+    quaternion & set_value( real q0, real q1, real q2, real q3 )
+    {
+        q[0] = q0;
+        q[1] = q1;
+        q[2] = q2;
+        q[3] = q3;
+        counter = 0;
+        return *this;
+    }
+
+    void get_value( vec3 &axis, real &radians ) const
+    {
+        radians = real(acos( q[3] ) * GLH_TWO);
+        if ( radians == GLH_ZERO )
+            axis = vec3( 0.0, 0.0, 1.0 );
+        else
+        {
+            axis.v[0] = q[0];
+            axis.v[1] = q[1];
+            axis.v[2] = q[2];
+            axis.normalize();
+        }
+    }
+
+    void get_value( matrix4 & m ) const
+    {
+        real s, xs, ys, zs, wx, wy, wz, xx, xy, xz, yy, yz, zz;
+
+        real norm = q[0] * q[0] + q[1] * q[1] + q[2] * q[2] + q[3] * q[3];
+
+        s = (equivalent(norm,GLH_ZERO)) ? GLH_ZERO : ( GLH_TWO / norm );
+
+        xs = q[0] * s;
+        ys = q[1] * s;
+        zs = q[2] * s;
+
+        wx = q[3] * xs;
+        wy = q[3] * ys;
+        wz = q[3] * zs;
+
+        xx = q[0] * xs;
+        xy = q[0] * ys;
+        xz = q[0] * zs;
+
+        yy = q[1] * ys;
+        yz = q[1] * zs;
+        zz = q[2] * zs;
+
+        m(0,0) = real( GLH_ONE - ( yy + zz ));
+        m(1,0) = real ( xy + wz );
+        m(2,0) = real ( xz - wy );
+
+        m(0,1) = real ( xy - wz );
+        m(1,1) = real ( GLH_ONE - ( xx + zz ));
+        m(2,1) = real ( yz + wx );
+
+        m(0,2) = real ( xz + wy );
+        m(1,2) = real ( yz - wx );
+        m(2,2) = real ( GLH_ONE - ( xx + yy ));
+
+        m(3,0) = m(3,1) = m(3,2) = m(0,3) = m(1,3) = m(2,3) = GLH_ZERO;
+        m(3,3) = GLH_ONE;
+    }
+
+    quaternion & set_value( const real * qp )
+    {
+        memcpy(q,qp,sizeof(real) * 4);
+
+        counter = 0;
+        return *this;
+    }
+
+    quaternion & set_value( const matrix4 & m )
+    {
+        real tr, s;
+        int i, j, k;
+        const int nxt[3] = { 1, 2, 0 };
+
+        tr = m(0,0) + m(1,1) + m(2,2);
+
+        if ( tr > GLH_ZERO )
+        {
+            s = real(sqrt( tr + m(3,3) ));
+            q[3] = real ( s * 0.5 );
+            s = real(0.5) / s;
+
+            q[0] = real ( ( m(1,2) - m(2,1) ) * s );
+            q[1] = real ( ( m(2,0) - m(0,2) ) * s );
+            q[2] = real ( ( m(0,1) - m(1,0) ) * s );
+        }
+        else
+        {
+            i = 0;
+            if ( m(1,1) > m(0,0) )
+              i = 1;
+
+            if ( m(2,2) > m(i,i) )
+              i = 2;
+
+            j = nxt[i];
+            k = nxt[j];
+
+            s = real(sqrt( ( m(i,j) - ( m(j,j) + m(k,k) )) + GLH_ONE ));
+
+            q[i] = real ( s * 0.5 );
+            s = real(0.5 / s);
+
+            q[3] = real ( ( m(j,k) - m(k,j) ) * s );
+            q[j] = real ( ( m(i,j) + m(j,i) ) * s );
+            q[k] = real ( ( m(i,k) + m(k,i) ) * s );
+        }
+
+        counter = 0;
+        return *this;
+    }
+
+    quaternion & set_value( const vec3 &axis, real theta )
+    {
+        real sqnorm = axis.square_norm();
+
+        if (sqnorm <= GLH_EPSILON)
+        {
+            // axis too small.
+            x = y = z = 0.0;
+            w = 1.0;
+        } 
+        else 
+        {
+            theta *= real(0.5);
+            real sin_theta = real(sin(theta));
+
+            if (!equivalent(sqnorm,GLH_ONE)) 
+              sin_theta /= real(sqrt(sqnorm));
+            x = sin_theta * axis.v[0];
+            y = sin_theta * axis.v[1];
+            z = sin_theta * axis.v[2];
+            w = real(cos(theta));
+        }
+        return *this;
+    }
+
+    quaternion & set_value( const vec3 & rotateFrom, const vec3 & rotateTo )
+    {
+        vec3 p1, p2;
+        real alpha;
+
+        p1 = rotateFrom; 
+        p1.normalize();
+        p2 = rotateTo;  
+        p2.normalize();
+
+        alpha = p1.dot(p2);
+
+        if(equivalent(alpha,GLH_ONE))
+        { 
+            *this = identity(); 
+            return *this; 
+        }
+
+        // ensures that the anti-parallel case leads to a positive dot
+        if(equivalent(alpha,-GLH_ONE))
+        {
+            vec3 v;
+
+            if(p1.v[0] != p1.v[1] || p1.v[0] != p1.v[2])
+                v = vec3(p1.v[1], p1.v[2], p1.v[0]);
+            else
+                v = vec3(-p1.v[0], p1.v[1], p1.v[2]);
+
+            v -= p1 * p1.dot(v);
+            v.normalize();
+
+            set_value(v, GLH_PI);
+            return *this;
+        }
+
+        p1 = p1.cross(p2);  
+        p1.normalize();
+        set_value(p1,real(acos(alpha)));
+
+        counter = 0;
+        return *this;
+    }
+
+    quaternion & set_value( const vec3 & from_look, const vec3 & from_up,
+                      const vec3 & to_look, const vec3 & to_up)
+    {
+            quaternion r_look = quaternion(from_look, to_look);
+            
+            vec3 rotated_from_up(from_up);
+            r_look.mult_vec(rotated_from_up);
+            
+            quaternion r_twist = quaternion(rotated_from_up, to_up);
+            
+            *this = r_twist;
+            *this *= r_look;
+            return *this;
+    }
+
+    quaternion & operator *= ( const quaternion & qr )
+    {
+        quaternion ql(*this);
+   
+        w = ql.w * qr.w - ql.x * qr.x - ql.y * qr.y - ql.z * qr.z;
+        x = ql.w * qr.x + ql.x * qr.w + ql.y * qr.z - ql.z * qr.y;
+        y = ql.w * qr.y + ql.y * qr.w + ql.z * qr.x - ql.x * qr.z;
+        z = ql.w * qr.z + ql.z * qr.w + ql.x * qr.y - ql.y * qr.x;
+
+        counter += qr.counter;
+        counter++;
+        counter_normalize();
+        return *this;
+    }
+
+    void normalize()
+    {
+        real rnorm = GLH_ONE / real(sqrt(w * w + x * x + y * y + z * z));
+        if (equivalent(rnorm, GLH_ZERO))
+            return;
+        x *= rnorm;
+        y *= rnorm;
+        z *= rnorm;
+        w *= rnorm;
+        counter = 0;
+    }
+
+    friend bool operator == ( const quaternion & q1, const quaternion & q2 );      
+
+    friend bool operator != ( const quaternion & q1, const quaternion & q2 );
+
+    friend quaternion operator * ( const quaternion & q1, const quaternion & q2 );
+
+    bool equals( const quaternion & r, real tolerance ) const
+    {
+        real t;
+
+        t = (
+                        (q[0]-r.q[0])*(q[0]-r.q[0]) +
+            (q[1]-r.q[1])*(q[1]-r.q[1]) +
+            (q[2]-r.q[2])*(q[2]-r.q[2]) +
+            (q[3]-r.q[3])*(q[3]-r.q[3]) );
+        if(t > GLH_EPSILON) 
+            return false;
+        return 1;
+    }
+
+    quaternion & conjugate()
+    {
+        q[0] *= -GLH_ONE;
+        q[1] *= -GLH_ONE;
+        q[2] *= -GLH_ONE;
+        return *this;
+    }
+
+    quaternion & invert()
+    {
+        return conjugate();
+    }
+
+    quaternion inverse() const
+    {
+        quaternion r = *this;
+        return r.invert();
+    }
+
+    //
+    // Quaternion multiplication with cartesian vector
+    // v' = q*v*q(star)
+    //
+    void mult_vec( const vec3 &src, vec3 &dst ) const
+    {
+        real v_coef = w * w - x * x - y * y - z * z;                     
+        real u_coef = GLH_TWO * (src.v[0] * x + src.v[1] * y + src.v[2] * z);  
+        real c_coef = GLH_TWO * w;                                       
+
+        dst.v[0] = v_coef * src.v[0] + u_coef * x + c_coef * (y * src.v[2] - z * src.v[1]);
+        dst.v[1] = v_coef * src.v[1] + u_coef * y + c_coef * (z * src.v[0] - x * src.v[2]);
+        dst.v[2] = v_coef * src.v[2] + u_coef * z + c_coef * (x * src.v[1] - y * src.v[0]);
+    }
+
+    void mult_vec( vec3 & src_and_dst) const
+    {
+        mult_vec(vec3(src_and_dst), src_and_dst);
+    }
+
+    void scale_angle( real scaleFactor )
+    {
+        vec3 axis;
+        real radians;
+
+        get_value(axis, radians);
+        radians *= scaleFactor;
+        set_value(axis, radians);
+    }
+
+    static quaternion slerp( const quaternion & p, const quaternion & q, real alpha )
+    {
+        quaternion r;
+
+        real cos_omega = p.x * q.x + p.y * q.y + p.z * q.z + p.w * q.w;
+        // if B is on opposite hemisphere from A, use -B instead
+      
+        int bflip;
+        if ( ( bflip = (cos_omega < GLH_ZERO)) )
+            cos_omega = -cos_omega;
+
+        // complementary interpolation parameter
+        real beta = GLH_ONE - alpha;     
+
+        if(cos_omega <= GLH_ONE - GLH_EPSILON)
+            return p;
+
+        real omega = real(acos(cos_omega));
+        real one_over_sin_omega = GLH_ONE / real(sin(omega));
+
+        beta    = real(sin(omega*beta)  * one_over_sin_omega);
+        alpha   = real(sin(omega*alpha) * one_over_sin_omega);
+
+        if (bflip)
+            alpha = -alpha;
+
+        r.x = beta * p.q[0]+ alpha * q.q[0];
+        r.y = beta * p.q[1]+ alpha * q.q[1];
+        r.z = beta * p.q[2]+ alpha * q.q[2];
+        r.w = beta * p.q[3]+ alpha * q.q[3];
+        return r;
+    }
+
+    static quaternion identity()
+    {
+        static quaternion ident( vec3( 0.0, 0.0, 0.0 ), GLH_ONE );
+        return ident;
+    }
+
+    real & operator []( int i )
+    {
+        assert(i < 4);
+        return q[i];
+    }
+
+    const real & operator []( int i ) const
+    {
+        assert(i < 4);
+        return q[i];
+    }
+
+    protected:
+
+        void counter_normalize()
+        {
+            if (counter > GLH_QUATERNION_NORMALIZATION_THRESHOLD)
+                normalize();
+        }
+
+        union 
+        {
+            struct 
+            {
+                real q[4];
+            };
+            struct 
+            {
+                real x;
+                real y;
+                real z;
+                real w;
+            };
+        };
+
+        // renormalization counter
+        unsigned char counter;
+    };
+
+    inline
+    bool operator == ( const quaternion & q1, const quaternion & q2 )
+    {
+        return (equivalent(q1.x, q2.x) &&
+                        equivalent(q1.y, q2.y) &&
+                        equivalent(q1.z, q2.z) &&
+                        equivalent(q1.w, q2.w) );
+    }
+
+    inline
+    bool operator != ( const quaternion & q1, const quaternion & q2 )
+    { 
+        return ! ( q1 == q2 ); 
+    }
+
+    inline
+    quaternion operator * ( const quaternion & q1, const quaternion & q2 )
+    {   
+        quaternion r(q1); 
+        r *= q2; 
+        return r; 
+    }
+  
+      
+    
+
+
+
+
+
+  
+  
+  class plane
+  {
+  public:
+          
+          plane()
+      {
+                  planedistance = 0.0;
+                  planenormal.set_value( 0.0, 0.0, 1.0 );
+      }
+          
+          
+          plane( const vec3 &p0, const vec3 &p1, const vec3 &p2 )
+      {
+                  vec3 v0 = p1 - p0;
+                  vec3 v1 = p2 - p0;
+                  planenormal = v0.cross(v1);  
+                  planenormal.normalize();
+                  planedistance = p0.dot(planenormal);
+      }
+          
+          plane( const vec3 &normal, real distance )
+      {
+                  planedistance = distance;
+                  planenormal = normal;
+                  planenormal.normalize();
+      }
+          
+          plane( const vec3 &normal, const vec3 &point )
+      {
+                  planenormal = normal;
+                  planenormal.normalize();
+                  planedistance = point.dot(planenormal);
+      }
+          
+          void offset( real d )
+      {
+                  planedistance += d;
+      }
+          
+          bool intersect( const line &l, vec3 &intersection ) const
+      {
+                  vec3 pos, dir;
+                  vec3 pn = planenormal;
+                  real pd = planedistance;
+                  
+                  pos = l.get_position();
+                  dir = l.get_direction();
+                  
+                  if(dir.dot(pn) == 0.0) return 0;
+                  pos -= pn*pd;
+                  // now we're talking about a plane passing through the origin
+                  if(pos.dot(pn) < 0.0) pn.negate();
+                  if(dir.dot(pn) > 0.0) dir.negate();
+                  vec3 ppos = pn * pos.dot(pn);
+                  pos = (ppos.length()/dir.dot(-pn))*dir;
+                  intersection = l.get_position();
+                  intersection += pos;
+                  return 1;
+      }
+          void transform( const matrix4 &matrix )
+      {
+                  matrix4 invtr = matrix.inverse();
+                  invtr = invtr.transpose();
+                  
+                  vec3 pntOnplane = planenormal * planedistance;
+                  vec3 newPntOnplane;
+                  vec3 newnormal;
+                  
+                  invtr.mult_dir_matrix(planenormal, newnormal);
+                  matrix.mult_vec_matrix(pntOnplane, newPntOnplane);
+                  
+                  newnormal.normalize();
+                  planenormal = newnormal;
+                  planedistance = newPntOnplane.dot(planenormal);
+      }
+          
+          bool is_in_half_space( const vec3 &point ) const
+      {
+                  
+                  if(( point.dot(planenormal) - planedistance) < 0.0)
+                          return 0;
+                  return 1;
+      }
+          
+          
+          real distance( const vec3 & point ) const 
+      {
+                  return planenormal.dot(point - planenormal*planedistance);
+      }
+          
+          const vec3 &get_normal() const
+      {
+                  return planenormal;
+      }
+          
+          
+          real get_distance_from_origin() const
+      {
+                  return planedistance;
+      }
+          
+          
+          friend bool operator == ( const plane & p1, const plane & p2 );
+          
+          
+          friend bool operator != ( const plane & p1, const plane & p2 );
+          
+  //protected:
+          vec3 planenormal;
+          real planedistance;
+  };
+  
+  inline
+  bool operator == (const plane & p1, const plane & p2 )
+  {
+          return (  p1.planedistance == p2.planedistance && p1.planenormal == p2.planenormal);
+  }
+  
+  inline
+  bool operator != ( const plane & p1, const plane & p2 )
+  { return  ! (p1 == p2); }
+  
+  
+
+  } // "ns_##GLH_REAL"
+
+  // make common typedefs...
+#ifdef GLH_REAL_IS_FLOAT
+  typedef GLH_REAL_NAMESPACE::vec2 vec2f;
+  typedef GLH_REAL_NAMESPACE::vec3 vec3f;
+  typedef GLH_REAL_NAMESPACE::vec4 vec4f;
+  typedef GLH_REAL_NAMESPACE::quaternion quaternionf;
+  typedef GLH_REAL_NAMESPACE::quaternion rotationf;
+  typedef GLH_REAL_NAMESPACE::line linef;
+  typedef GLH_REAL_NAMESPACE::plane planef;
+  typedef GLH_REAL_NAMESPACE::matrix4 matrix4f;
+#endif
+
+  
+
+
+}  // namespace glh
+
+
+
+#endif
+