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diff --git a/linden/indra/llmath/llcamera.cpp b/linden/indra/llmath/llcamera.cpp
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+++ b/linden/indra/llmath/llcamera.cpp
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+/** 
+ * @file llcamera.cpp
+ * @brief Implementation of the LLCamera class.
+ *
+ * Copyright (c) 2000-2007, Linden Research, Inc.
+ * 
+ * The source code in this file ("Source Code") is provided by Linden Lab
+ * to you under the terms of the GNU General Public License, version 2.0
+ * ("GPL"), unless you have obtained a separate licensing agreement
+ * ("Other License"), formally executed by you and Linden Lab.  Terms of
+ * the GPL can be found in doc/GPL-license.txt in this distribution, or
+ * online at http://secondlife.com/developers/opensource/gplv2
+ * 
+ * There are special exceptions to the terms and conditions of the GPL as
+ * it is applied to this Source Code. View the full text of the exception
+ * in the file doc/FLOSS-exception.txt in this software distribution, or
+ * online at http://secondlife.com/developers/opensource/flossexception
+ * 
+ * By copying, modifying or distributing this software, you acknowledge
+ * that you have read and understood your obligations described above,
+ * and agree to abide by those obligations.
+ * 
+ * ALL LINDEN LAB SOURCE CODE IS PROVIDED "AS IS." LINDEN LAB MAKES NO
+ * WARRANTIES, EXPRESS, IMPLIED OR OTHERWISE, REGARDING ITS ACCURACY,
+ * COMPLETENESS OR PERFORMANCE.
+ */
+
+#include "linden_common.h"
+
+#include "llmath.h"
+#include "llcamera.h"
+
+// ---------------- Constructors and destructors ----------------
+
+LLCamera::LLCamera() :
+        LLCoordFrame(),
+        mView(DEFAULT_FIELD_OF_VIEW),
+        mAspect(DEFAULT_ASPECT_RATIO),
+        mViewHeightInPixels( -1 ),                      // invalid height
+        mNearPlane(DEFAULT_NEAR_PLANE),
+        mFarPlane(DEFAULT_FAR_PLANE),
+        mFixedDistance(-1.f)
+{
+        calculateFrustumPlanes();
+} 
+
+
+LLCamera::LLCamera(F32 z_field_of_view, F32 aspect_ratio, S32 view_height_in_pixels, F32 near_plane, F32 far_plane) :
+        LLCoordFrame(),
+        mView(z_field_of_view),
+        mAspect(aspect_ratio),
+        mViewHeightInPixels(view_height_in_pixels),
+        mNearPlane(near_plane),
+        mFarPlane(far_plane),
+        mFixedDistance(-1.f)
+{
+        if (mView < MIN_FIELD_OF_VIEW)                  { mView = MIN_FIELD_OF_VIEW; }
+        else if (mView > MAX_FIELD_OF_VIEW)             { mView = MAX_FIELD_OF_VIEW; }
+
+        if (mAspect < MIN_ASPECT_RATIO)                 { mAspect = MIN_ASPECT_RATIO; }
+        else if (mAspect > MAX_ASPECT_RATIO)    { mAspect = MAX_ASPECT_RATIO; }
+
+        if (mNearPlane < MIN_NEAR_PLANE)                { mNearPlane = MIN_NEAR_PLANE; }
+        else if (mNearPlane > MAX_NEAR_PLANE)   { mNearPlane = MAX_NEAR_PLANE; }
+
+        if (mFarPlane < 0)                                              { mFarPlane = DEFAULT_FAR_PLANE; }
+        else if (mFarPlane < MIN_FAR_PLANE)             { mFarPlane = MIN_FAR_PLANE; }
+        else if (mFarPlane > MAX_FAR_PLANE)             { mFarPlane = MAX_FAR_PLANE; }
+
+        calculateFrustumPlanes();
+} 
+
+
+
+// ---------------- LLCamera::setFoo() member functions ----------------
+
+void LLCamera::setView(F32 field_of_view) 
+{
+        mView = field_of_view;
+        if (mView < MIN_FIELD_OF_VIEW)                  { mView = MIN_FIELD_OF_VIEW; }
+        else if (mView > MAX_FIELD_OF_VIEW)             { mView = MAX_FIELD_OF_VIEW; }
+        calculateFrustumPlanes();
+}
+
+void LLCamera::setViewHeightInPixels(S32 height)
+{
+        mViewHeightInPixels = height;
+
+        // Don't really need to do this, but update the pixel meter ratio with it.
+        calculateFrustumPlanes();
+}
+
+void LLCamera::setAspect(F32 aspect_ratio) 
+{
+        mAspect = aspect_ratio;
+        if (mAspect < MIN_ASPECT_RATIO)                 { mAspect = MIN_ASPECT_RATIO; }
+        else if (mAspect > MAX_ASPECT_RATIO)    { mAspect = MAX_ASPECT_RATIO; }
+        calculateFrustumPlanes();
+}
+
+
+void LLCamera::setNear(F32 near_plane) 
+{
+        mNearPlane = near_plane;
+        if (mNearPlane < MIN_NEAR_PLANE)                { mNearPlane = MIN_NEAR_PLANE; }
+        else if (mNearPlane > MAX_NEAR_PLANE)   { mNearPlane = MAX_NEAR_PLANE; }
+        calculateFrustumPlanes();
+}
+
+
+void LLCamera::setFar(F32 far_plane) 
+{
+        mFarPlane = far_plane;
+        if (mFarPlane < MIN_FAR_PLANE)                  { mFarPlane = MIN_FAR_PLANE; }
+        else if (mFarPlane > MAX_FAR_PLANE)             { mFarPlane = MAX_FAR_PLANE; }
+        calculateFrustumPlanes();
+}
+
+
+// ---------------- read/write to buffer ---------------- 
+
+size_t LLCamera::writeFrustumToBuffer(char *buffer) const
+{
+        memcpy(buffer, &mView, sizeof(F32));
+        buffer += sizeof(F32);
+        memcpy(buffer, &mAspect, sizeof(F32));
+        buffer += sizeof(F32);
+        memcpy(buffer, &mNearPlane, sizeof(F32));
+        buffer += sizeof(F32);
+        memcpy(buffer, &mFarPlane, sizeof(F32));
+        return 4*sizeof(F32);
+}
+
+size_t LLCamera::readFrustumFromBuffer(const char *buffer)
+{
+        memcpy(&mView, buffer, sizeof(F32));
+        buffer += sizeof(F32);
+        memcpy(&mAspect, buffer, sizeof(F32));
+        buffer += sizeof(F32);
+        memcpy(&mNearPlane, buffer, sizeof(F32));
+        buffer += sizeof(F32);
+        memcpy(&mFarPlane, buffer, sizeof(F32));
+        return 4*sizeof(F32);
+}
+
+
+// ---------------- test methods  ---------------- 
+
+int LLCamera::AABBInFrustum(const LLVector3 &center, const LLVector3& radius) 
+{
+        static const LLVector3 scaler[] = {
+                LLVector3(-1,-1,-1),
+                LLVector3( 1,-1,-1),
+                LLVector3(-1, 1,-1),
+                LLVector3( 1, 1,-1),
+                LLVector3(-1,-1, 1),
+                LLVector3( 1,-1, 1),
+                LLVector3(-1, 1, 1),
+                LLVector3( 1, 1, 1)
+        };
+
+        U8 mask = 0;
+        S32 result = 2;
+
+        for (int i = 0; i < 6; i++)
+        {
+                mask = mAgentPlaneMask[i];
+                LLPlane p = mAgentPlanes[i];
+                LLVector3 n = LLVector3(p);
+                float d = p.mV[3];
+                LLVector3 rscale = radius.scaledVec(scaler[mask]);
+
+                LLVector3 minp = center - rscale;
+                LLVector3 maxp = center + rscale;
+
+                if (n * minp > -d) 
+                {
+                        return 0;
+                }
+        
+                if (n * maxp > -d)
+                {
+                        result = 1;
+                }
+        }
+
+        return result;
+}
+
+int LLCamera::sphereInFrustumQuick(const LLVector3 &sphere_center, const F32 radius) 
+{
+        LLVector3 dist = sphere_center-mFrustCenter;
+        float dsq = dist * dist;
+        float rsq = mFarPlane*0.5f + radius;
+        rsq *= rsq;
+
+        if (dsq < rsq) 
+        {
+                return 1;
+        }
+        
+        return 0;       
+}
+
+// HACK: This version is still around because the version below doesn't work
+// unless the agent planes are initialized.
+// Return 1 if sphere is in frustum, 2 if fully in frustum, otherwise 0.
+// NOTE: 'center' is in absolute frame.
+int LLCamera::sphereInFrustumOld(const LLVector3 &sphere_center, const F32 radius) const 
+{
+        // Returns 1 if sphere is in frustum, 0 if not.
+        // modified so that default view frust is along X with Z vertical
+        F32 x, y, z, rightDist, leftDist, topDist, bottomDist;
+
+        // Subtract the view position 
+        //LLVector3 relative_center;
+        //relative_center = sphere_center - getOrigin();
+        LLVector3 rel_center(sphere_center);
+        rel_center -= mOrigin;
+
+        bool all_in = TRUE;
+
+        // Transform relative_center.x to camera frame
+        x = mXAxis * rel_center;
+        if (x < MIN_NEAR_PLANE - radius)
+        {
+                return 0;
+        }
+        else if (x < MIN_NEAR_PLANE + radius)
+        {
+                all_in = FALSE;
+        }
+
+        if (x > mFarPlane + radius)
+        {
+                return 0;
+        }
+        else if (x > mFarPlane - radius)
+        {
+                all_in = FALSE;
+        }
+
+        // Transform relative_center.y to camera frame
+        y = mYAxis * rel_center;
+
+        // distance to plane is the dot product of (x, y, 0) * plane_normal
+        rightDist = x * mLocalPlanes[PLANE_RIGHT][VX] + y * mLocalPlanes[PLANE_RIGHT][VY];
+        if (rightDist < -radius)
+        {
+                return 0;
+        }
+        else if (rightDist < radius)
+        {
+                all_in = FALSE;
+        }
+
+        leftDist = x * mLocalPlanes[PLANE_LEFT][VX] + y * mLocalPlanes[PLANE_LEFT][VY];
+        if (leftDist < -radius)
+        {
+                return 0;
+        }
+        else if (leftDist < radius)
+        {
+                all_in = FALSE;
+        }
+
+        // Transform relative_center.y to camera frame
+        z = mZAxis * rel_center;
+
+        topDist = x * mLocalPlanes[PLANE_TOP][VX] + z * mLocalPlanes[PLANE_TOP][VZ];
+        if (topDist < -radius)
+        {
+                return 0;
+        }
+        else if (topDist < radius)
+        {
+                all_in = FALSE;
+        }
+
+        bottomDist = x * mLocalPlanes[PLANE_BOTTOM][VX] + z * mLocalPlanes[PLANE_BOTTOM][VZ];
+        if (bottomDist < -radius)
+        {
+                return 0;
+        }
+        else if (bottomDist < radius)
+        {
+                all_in = FALSE;
+        }
+
+        if (all_in)
+        {
+                return 2;
+        }
+
+        return 1;
+}
+
+
+// HACK: This (presumably faster) version only currently works if you set up the
+// frustum planes using GL.  At some point we should get those planes through another
+// mechanism, and then we can get rid of the "old" version above.
+
+// Return 1 if sphere is in frustum, 2 if fully in frustum, otherwise 0.
+// NOTE: 'center' is in absolute frame.
+int LLCamera::sphereInFrustum(const LLVector3 &sphere_center, const F32 radius) const 
+{
+        // Returns 1 if sphere is in frustum, 0 if not.
+        int res = 2;
+        for (int i = 0; i < 6; i++)
+        {
+                float d = mAgentPlanes[i].dist(sphere_center);
+
+                if (d > radius) 
+                {
+                        return 0;
+                }
+
+                if (d > -radius)
+                {
+                        res = 1;
+                }
+        }
+
+        return res;
+}
+
+
+// return height of a sphere of given radius, located at center, in pixels
+F32 LLCamera::heightInPixels(const LLVector3 &center, F32 radius ) const
+{
+        if (radius == 0.f) return 0.f;
+
+        // If height initialized
+        if (mViewHeightInPixels > -1)
+        {
+                // Convert sphere to coord system with 0,0,0 at camera
+                LLVector3 vec = center - mOrigin;
+
+                // Compute distance to sphere
+                F32 dist = vec.magVec();
+
+                // Calculate angle of whole object
+                F32 angle = 2.0f * (F32) atan2(radius, dist);
+
+                // Calculate fraction of field of view
+                F32 fraction_of_fov = angle / mView;
+
+                // Compute number of pixels tall, based on vertical field of view
+                return (fraction_of_fov * mViewHeightInPixels);
+        }
+        else
+        {
+                // return invalid height
+                return -1.0f;
+        }
+}
+
+// If pos is visible, return the distance from pos to the camera.
+// Use fudge distance to scale rad against top/bot/left/right planes
+// Otherwise, return -distance
+F32 LLCamera::visibleDistance(const LLVector3 &pos, F32 rad, F32 fudgedist, U32 planemask) const
+{
+        if (mFixedDistance > 0)
+        {
+                return mFixedDistance;
+        }
+        LLVector3 dvec = pos - mOrigin;
+        // Check visibility
+        F32 dist = dvec.magVec();
+        if (dist > rad)
+        {
+                F32 dp,tdist;
+                dp = dvec * mXAxis;
+                if (dp < -rad)
+                        return -dist;
+
+                rad *= fudgedist;
+                LLVector3 tvec(pos);
+                for (int p=0; p<PLANE_NUM; p++)
+                {
+                        if (!(planemask & (1<<p)))
+                                continue;
+                        tdist = -(mWorldPlanes[p].dist(tvec));
+                        if (tdist > rad)
+                                return -dist;
+                }
+        }
+        return dist;
+}
+
+// Like visibleDistance, except uses mHorizPlanes[], which are left and right
+//  planes perpindicular to (0,0,1) in world space
+F32 LLCamera::visibleHorizDistance(const LLVector3 &pos, F32 rad, F32 fudgedist, U32 planemask) const
+{
+        if (mFixedDistance > 0)
+        {
+                return mFixedDistance;
+        }
+        LLVector3 dvec = pos - mOrigin;
+        // Check visibility
+        F32 dist = dvec.magVec();
+        if (dist > rad)
+        {
+                rad *= fudgedist;
+                LLVector3 tvec(pos);
+                for (int p=0; p<HORIZ_PLANE_NUM; p++)
+                {
+                        if (!(planemask & (1<<p)))
+                                continue;
+                        F32 tdist = -(mHorizPlanes[p].dist(tvec));
+                        if (tdist > rad)
+                                return -dist;
+                }
+        }
+        return dist;
+}
+
+// ---------------- friends and operators ----------------  
+
+std::ostream& operator<<(std::ostream &s, const LLCamera &C) 
+{
+        s << "{ \n";
+        s << "  Center = " << C.getOrigin() << "\n";
+        s << "  AtAxis = " << C.getXAxis() << "\n";
+        s << "  LeftAxis = " << C.getYAxis() << "\n";
+        s << "  UpAxis = " << C.getZAxis() << "\n";
+        s << "  View = " << C.getView() << "\n";
+        s << "  Aspect = " << C.getAspect() << "\n";
+        s << "  NearPlane   = " << C.mNearPlane << "\n";
+        s << "  FarPlane    = " << C.mFarPlane << "\n";
+        s << "  TopPlane    = " << C.mLocalPlanes[LLCamera::PLANE_TOP][VX] << "  " 
+                                                        << C.mLocalPlanes[LLCamera::PLANE_TOP][VY] << "  " 
+                                                        << C.mLocalPlanes[LLCamera::PLANE_TOP][VZ] << "\n";
+        s << "  BottomPlane = " << C.mLocalPlanes[LLCamera::PLANE_BOTTOM][VX] << "  " 
+                                                        << C.mLocalPlanes[LLCamera::PLANE_BOTTOM][VY] << "  " 
+                                                        << C.mLocalPlanes[LLCamera::PLANE_BOTTOM][VZ] << "\n";
+        s << "  LeftPlane   = " << C.mLocalPlanes[LLCamera::PLANE_LEFT][VX] << "  " 
+                                                        << C.mLocalPlanes[LLCamera::PLANE_LEFT][VY] << "  " 
+                                                        << C.mLocalPlanes[LLCamera::PLANE_LEFT][VZ] << "\n";
+        s << "  RightPlane  = " << C.mLocalPlanes[LLCamera::PLANE_RIGHT][VX] << "  " 
+                                                        << C.mLocalPlanes[LLCamera::PLANE_RIGHT][VY] << "  " 
+                                                        << C.mLocalPlanes[LLCamera::PLANE_RIGHT][VZ] << "\n";
+        s << "}";
+        return s;
+}
+
+
+
+// ----------------  private member functions ----------------
+
+void LLCamera::calculateFrustumPlanes() 
+{
+        // The planes only change when any of the frustum descriptions change.
+        // They are not affected by changes of the position of the Frustum
+        // because they are known in the view frame and the position merely
+        // provides information on how to get from the absolute frame to the 
+        // view frame.
+
+        F32 left,right,top,bottom;
+        top = mFarPlane * (F32)tanf(0.5f * mView);
+        bottom = -top;
+        left = top * mAspect;
+        right = -left;
+
+        calculateFrustumPlanes(left, right, top, bottom);
+}
+
+LLPlane planeFromPoints(LLVector3 p1, LLVector3 p2, LLVector3 p3)
+{
+        LLVector3 n = ((p2-p1)%(p3-p1));
+        n.normVec();
+
+        return LLPlane(p1, n);
+}
+
+
+void LLCamera::calcAgentFrustumPlanes(LLVector3* frust)
+{
+
+        for (int i = 0; i < 8; i++)
+        {
+                mAgentFrustum[i] = frust[i];
+        }
+
+        //frust contains the 8 points of the frustum, calculate 6 planes
+
+        //order of planes is important, keep most likely to fail in the front of the list
+
+        //near - frust[0], frust[1], frust[2]
+        mAgentPlanes[2] = planeFromPoints(frust[0], frust[1], frust[2]);
+
+        //far  
+        mAgentPlanes[5] = planeFromPoints(frust[5], frust[4], frust[6]);
+
+        //left  
+        mAgentPlanes[0] = planeFromPoints(frust[4], frust[0], frust[7]);
+
+        //right  
+        mAgentPlanes[1] = planeFromPoints(frust[1], frust[5], frust[6]);
+
+        //top  
+        mAgentPlanes[4] = planeFromPoints(frust[3], frust[2], frust[6]);
+
+        //bottom  
+        mAgentPlanes[3] = planeFromPoints(frust[1], frust[0], frust[4]);
+
+        //cache plane octant facing mask for use in AABBInFrustum
+        for (int i = 0; i < 8; i++)
+        {
+                U8 mask = 0;
+                LLPlane p = mAgentPlanes[i];
+                LLVector3 n = LLVector3(p);
+
+                if (n.mV[0] >= 0)
+                {
+                        mask |= 1;
+                }
+                if (n.mV[1] >= 0)
+                {
+                        mask |= 2;
+                }
+                if (n.mV[2] >= 0)
+                {
+                        mask |= 4;
+                }
+                mAgentPlaneMask[i] = mask;
+        }
+}
+
+void LLCamera::calculateFrustumPlanes(F32 left, F32 right, F32 top, F32 bottom)
+{
+        LLVector3 a, b, c;
+
+        // For each plane we need to define 3 points (LLVector3's) in camera view space.  
+        // The order in which we pass the points to planeFromPoints() matters, because the 
+        // plane normal has a degeneracy of 2; we want it pointing _into_ the frustum. 
+
+        a.setVec(0.0f, 0.0f, 0.0f);
+        b.setVec(mFarPlane, right, top);
+        c.setVec(mFarPlane, right, bottom);
+        mLocalPlanes[PLANE_RIGHT].setVec(a, b, c);
+
+        c.setVec(mFarPlane, left, top);
+        mLocalPlanes[PLANE_TOP].setVec(a, c, b);
+
+        b.setVec(mFarPlane, left, bottom);
+        mLocalPlanes[PLANE_LEFT].setVec(a, b, c);
+
+        c.setVec(mFarPlane, right, bottom);
+        mLocalPlanes[PLANE_BOTTOM].setVec( a, c, b); 
+
+        //calculate center and radius squared of frustum in world absolute coordinates
+        mFrustCenter = X_AXIS*mFarPlane*0.5f;
+        mFrustCenter = transformToAbsolute(mFrustCenter);
+        mFrustRadiusSquared = mFarPlane*0.5f;
+        mFrustRadiusSquared *= mFrustRadiusSquared * 1.05f; //pad radius squared by 5%
+}
+
+// x and y are in WINDOW space, so x = Y-Axis (left/right), y= Z-Axis(Up/Down)
+void LLCamera::calculateFrustumPlanesFromWindow(F32 x1, F32 y1, F32 x2, F32 y2)
+{
+        F32 bottom, top, left, right;
+        F32 view_height = (F32)tanf(0.5f * mView) * mFarPlane;
+        F32 view_width = view_height * mAspect;
+        
+        left =   x1 * -2.f * view_width;
+        right =  x2 * -2.f * view_width;
+        bottom = y1 * 2.f * view_height; 
+        top =    y2 * 2.f * view_height;
+
+        calculateFrustumPlanes(left, right, top, bottom);
+}
+
+void LLCamera::calculateWorldFrustumPlanes() 
+{
+        F32 d;
+        LLVector3 center = mOrigin - mXAxis*mNearPlane;
+        mWorldPlanePos = center;
+        for (int p=0; p<4; p++)
+        {
+                LLVector3 pnorm = LLVector3(mLocalPlanes[p]);
+                LLVector3 norm = rotateToAbsolute(pnorm);
+                norm.normVec();
+                d = -(center * norm);
+                mWorldPlanes[p] = LLPlane(norm, d);
+        }
+        // horizontal planes, perpindicular to (0,0,1);
+        LLVector3 zaxis(0, 0, 1.0f);
+        F32 yaw = getYaw();
+        {
+                LLVector3 tnorm = LLVector3(mLocalPlanes[PLANE_LEFT]);
+                tnorm.rotVec(yaw, zaxis);
+                d = -(mOrigin * tnorm);
+                mHorizPlanes[HORIZ_PLANE_LEFT] = LLPlane(tnorm, d);
+        }
+        {
+                LLVector3 tnorm = LLVector3(mLocalPlanes[PLANE_RIGHT]);
+                tnorm.rotVec(yaw, zaxis);
+                d = -(mOrigin * tnorm);
+                mHorizPlanes[HORIZ_PLANE_RIGHT] = LLPlane(tnorm, d);
+        }
+}
+
+// NOTE: this is the OpenGL matrix that will transform the default OpenGL view 
+// (-Z=at, Y=up) to the default view of the LLCamera class (X=at, Z=up):
+// 
+// F32 cfr_transform =  {  0.f,  0.f, -1.f,  0.f,   // -Z becomes X
+//                                                -1.f,  0.f,  0.f,  0.f,   // -X becomes Y
+//                                         0.f,  1.f,  0.f,  0.f,   //  Y becomes Z
+//                                                 0.f,  0.f,  0.f,  1.f };