svn merge ^/branches/released . --username marha

1 files changed, 793 insertions, 0 deletions

diff --git a/mesalib/src/mesa/main/matrix.c b/mesalib/src/mesa/main/matrix.c
new file mode 100644
index 000000000..ebc3cbd59
--- /dev/null
+++ b/mesalib/src/mesa/main/matrix.c
@@ -0,0 +1,793 @@
+/*
+ * Mesa 3-D graphics library
+ * Version:  7.5
+ *
+ * Copyright (C) 1999-2008  Brian Paul   All Rights Reserved.
+ * Copyright (C) 2009  VMware, Inc.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+
+/**
+ * \file matrix.c
+ * Matrix operations.
+ *
+ * \note
+ * -# 4x4 transformation matrices are stored in memory in column major order.
+ * -# Points/vertices are to be thought of as column vectors.
+ * -# Transformation of a point p by a matrix M is: p' = M * p
+ */
+
+
+#include "glheader.h"
+#include "imports.h"
+#include "context.h"
+#include "enums.h"
+#include "macros.h"
+#include "matrix.h"
+#include "mtypes.h"
+#include "math/m_matrix.h"
+
+
+/**
+ * Apply a perspective projection matrix.
+ *
+ * \param left left clipping plane coordinate.
+ * \param right right clipping plane coordinate.
+ * \param bottom bottom clipping plane coordinate.
+ * \param top top clipping plane coordinate.
+ * \param nearval distance to the near clipping plane.
+ * \param farval distance to the far clipping plane.
+ *
+ * \sa glFrustum().
+ *
+ * Flushes vertices and validates parameters. Calls _math_matrix_frustum() with
+ * the top matrix of the current matrix stack and sets
+ * __GLcontextRec::NewState.
+ */
+void GLAPIENTRY
+_mesa_Frustum( GLdouble left, GLdouble right,
+               GLdouble bottom, GLdouble top,
+               GLdouble nearval, GLdouble farval )
+{
+   GET_CURRENT_CONTEXT(ctx);
+   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
+
+   if (nearval <= 0.0 ||
+       farval <= 0.0 ||
+       nearval == farval ||
+       left == right ||
+       top == bottom)
+   {
+      _mesa_error( ctx,  GL_INVALID_VALUE, "glFrustum" );
+      return;
+   }
+
+   _math_matrix_frustum( ctx->CurrentStack->Top,
+                         (GLfloat) left, (GLfloat) right, 
+			 (GLfloat) bottom, (GLfloat) top, 
+			 (GLfloat) nearval, (GLfloat) farval );
+   ctx->NewState |= ctx->CurrentStack->DirtyFlag;
+}
+
+
+/**
+ * Apply an orthographic projection matrix.
+ *
+ * \param left left clipping plane coordinate.
+ * \param right right clipping plane coordinate.
+ * \param bottom bottom clipping plane coordinate.
+ * \param top top clipping plane coordinate.
+ * \param nearval distance to the near clipping plane.
+ * \param farval distance to the far clipping plane.
+ *
+ * \sa glOrtho().
+ *
+ * Flushes vertices and validates parameters. Calls _math_matrix_ortho() with
+ * the top matrix of the current matrix stack and sets
+ * __GLcontextRec::NewState.
+ */
+void GLAPIENTRY
+_mesa_Ortho( GLdouble left, GLdouble right,
+             GLdouble bottom, GLdouble top,
+             GLdouble nearval, GLdouble farval )
+{
+   GET_CURRENT_CONTEXT(ctx);
+   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
+
+   if (MESA_VERBOSE & VERBOSE_API)
+      _mesa_debug(ctx, "glOrtho(%f, %f, %f, %f, %f, %f)\n",
+                  left, right, bottom, top, nearval, farval);
+
+   if (left == right ||
+       bottom == top ||
+       nearval == farval)
+   {
+      _mesa_error( ctx,  GL_INVALID_VALUE, "glOrtho" );
+      return;
+   }
+
+   _math_matrix_ortho( ctx->CurrentStack->Top,
+                       (GLfloat) left, (GLfloat) right, 
+		       (GLfloat) bottom, (GLfloat) top, 
+		       (GLfloat) nearval, (GLfloat) farval );
+   ctx->NewState |= ctx->CurrentStack->DirtyFlag;
+}
+
+
+/**
+ * Set the current matrix stack.
+ *
+ * \param mode matrix stack.
+ *
+ * \sa glMatrixMode().
+ *
+ * Flushes the vertices, validates the parameter and updates
+ * __GLcontextRec::CurrentStack and gl_transform_attrib::MatrixMode with the
+ * specified matrix stack.
+ */
+void GLAPIENTRY
+_mesa_MatrixMode( GLenum mode )
+{
+   GET_CURRENT_CONTEXT(ctx);
+   ASSERT_OUTSIDE_BEGIN_END(ctx);
+
+   if (ctx->Transform.MatrixMode == mode && mode != GL_TEXTURE)
+      return;
+   FLUSH_VERTICES(ctx, _NEW_TRANSFORM);
+
+   switch (mode) {
+   case GL_MODELVIEW:
+      ctx->CurrentStack = &ctx->ModelviewMatrixStack;
+      break;
+   case GL_PROJECTION:
+      ctx->CurrentStack = &ctx->ProjectionMatrixStack;
+      break;
+   case GL_TEXTURE:
+      /* This error check is disabled because if we're called from
+       * glPopAttrib() when the active texture unit is >= MaxTextureCoordUnits
+       * we'll generate an unexpected error.
+       * From the GL_ARB_vertex_shader spec it sounds like we should instead
+       * do error checking in other places when we actually try to access
+       * texture matrices beyond MaxTextureCoordUnits.
+       */
+#if 0
+      if (ctx->Texture.CurrentUnit >= ctx->Const.MaxTextureCoordUnits) {
+         _mesa_error(ctx, GL_INVALID_OPERATION, "glMatrixMode(invalid tex unit %d)",
+                     ctx->Texture.CurrentUnit);
+         return;
+      }
+#endif
+      ASSERT(ctx->Texture.CurrentUnit < Elements(ctx->TextureMatrixStack));
+      ctx->CurrentStack = &ctx->TextureMatrixStack[ctx->Texture.CurrentUnit];
+      break;
+   case GL_COLOR:
+      ctx->CurrentStack = &ctx->ColorMatrixStack;
+      break;
+   case GL_MATRIX0_NV:
+   case GL_MATRIX1_NV:
+   case GL_MATRIX2_NV:
+   case GL_MATRIX3_NV:
+   case GL_MATRIX4_NV:
+   case GL_MATRIX5_NV:
+   case GL_MATRIX6_NV:
+   case GL_MATRIX7_NV:
+      if (ctx->Extensions.NV_vertex_program) {
+         ctx->CurrentStack = &ctx->ProgramMatrixStack[mode - GL_MATRIX0_NV];
+      }
+      else {
+         _mesa_error( ctx,  GL_INVALID_ENUM, "glMatrixMode(mode)" );
+         return;
+      }
+      break;
+   case GL_MATRIX0_ARB:
+   case GL_MATRIX1_ARB:
+   case GL_MATRIX2_ARB:
+   case GL_MATRIX3_ARB:
+   case GL_MATRIX4_ARB:
+   case GL_MATRIX5_ARB:
+   case GL_MATRIX6_ARB:
+   case GL_MATRIX7_ARB:
+      if (ctx->Extensions.ARB_vertex_program ||
+          ctx->Extensions.ARB_fragment_program) {
+         const GLuint m = mode - GL_MATRIX0_ARB;
+         if (m > ctx->Const.MaxProgramMatrices) {
+            _mesa_error(ctx, GL_INVALID_ENUM,
+                        "glMatrixMode(GL_MATRIX%d_ARB)", m);
+            return;
+         }
+         ctx->CurrentStack = &ctx->ProgramMatrixStack[m];
+      }
+      else {
+         _mesa_error( ctx,  GL_INVALID_ENUM, "glMatrixMode(mode)" );
+         return;
+      }
+      break;
+   default:
+      _mesa_error( ctx,  GL_INVALID_ENUM, "glMatrixMode(mode)" );
+      return;
+   }
+
+   ctx->Transform.MatrixMode = mode;
+}
+
+
+/**
+ * Push the current matrix stack.
+ *
+ * \sa glPushMatrix().
+ * 
+ * Verifies the current matrix stack is not full, and duplicates the top-most
+ * matrix in the stack. Marks __GLcontextRec::NewState with the stack dirty
+ * flag.
+ */
+void GLAPIENTRY
+_mesa_PushMatrix( void )
+{
+   GET_CURRENT_CONTEXT(ctx);
+   struct gl_matrix_stack *stack = ctx->CurrentStack;
+   ASSERT_OUTSIDE_BEGIN_END(ctx);
+
+   if (MESA_VERBOSE&VERBOSE_API)
+      _mesa_debug(ctx, "glPushMatrix %s\n",
+                  _mesa_lookup_enum_by_nr(ctx->Transform.MatrixMode));
+
+   if (stack->Depth + 1 >= stack->MaxDepth) {
+      if (ctx->Transform.MatrixMode == GL_TEXTURE) {
+         _mesa_error(ctx,  GL_STACK_OVERFLOW,
+                     "glPushMatrix(mode=GL_TEXTURE, unit=%d)",
+                      ctx->Texture.CurrentUnit);
+      }
+      else {
+         _mesa_error(ctx,  GL_STACK_OVERFLOW, "glPushMatrix(mode=%s)",
+                     _mesa_lookup_enum_by_nr(ctx->Transform.MatrixMode));
+      }
+      return;
+   }
+   _math_matrix_copy( &stack->Stack[stack->Depth + 1],
+                      &stack->Stack[stack->Depth] );
+   stack->Depth++;
+   stack->Top = &(stack->Stack[stack->Depth]);
+   ctx->NewState |= stack->DirtyFlag;
+}
+
+
+/**
+ * Pop the current matrix stack.
+ *
+ * \sa glPopMatrix().
+ * 
+ * Flushes the vertices, verifies the current matrix stack is not empty, and
+ * moves the stack head down. Marks __GLcontextRec::NewState with the dirty
+ * stack flag.
+ */
+void GLAPIENTRY
+_mesa_PopMatrix( void )
+{
+   GET_CURRENT_CONTEXT(ctx);
+   struct gl_matrix_stack *stack = ctx->CurrentStack;
+   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
+
+   if (MESA_VERBOSE&VERBOSE_API)
+      _mesa_debug(ctx, "glPopMatrix %s\n",
+                  _mesa_lookup_enum_by_nr(ctx->Transform.MatrixMode));
+
+   if (stack->Depth == 0) {
+      if (ctx->Transform.MatrixMode == GL_TEXTURE) {
+         _mesa_error(ctx,  GL_STACK_UNDERFLOW,
+                     "glPopMatrix(mode=GL_TEXTURE, unit=%d)",
+                      ctx->Texture.CurrentUnit);
+      }
+      else {
+         _mesa_error(ctx,  GL_STACK_UNDERFLOW, "glPopMatrix(mode=%s)",
+                     _mesa_lookup_enum_by_nr(ctx->Transform.MatrixMode));
+      }
+      return;
+   }
+   stack->Depth--;
+   stack->Top = &(stack->Stack[stack->Depth]);
+   ctx->NewState |= stack->DirtyFlag;
+}
+
+
+/**
+ * Replace the current matrix with the identity matrix.
+ *
+ * \sa glLoadIdentity().
+ *
+ * Flushes the vertices and calls _math_matrix_set_identity() with the top-most
+ * matrix in the current stack. Marks __GLcontextRec::NewState with the stack
+ * dirty flag.
+ */
+void GLAPIENTRY
+_mesa_LoadIdentity( void )
+{
+   GET_CURRENT_CONTEXT(ctx);
+   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
+
+   if (MESA_VERBOSE & VERBOSE_API)
+      _mesa_debug(ctx, "glLoadIdentity()");
+
+   _math_matrix_set_identity( ctx->CurrentStack->Top );
+   ctx->NewState |= ctx->CurrentStack->DirtyFlag;
+}
+
+
+/**
+ * Replace the current matrix with a given matrix.
+ *
+ * \param m matrix.
+ *
+ * \sa glLoadMatrixf().
+ *
+ * Flushes the vertices and calls _math_matrix_loadf() with the top-most matrix
+ * in the current stack and the given matrix. Marks __GLcontextRec::NewState
+ * with the dirty stack flag.
+ */
+void GLAPIENTRY
+_mesa_LoadMatrixf( const GLfloat *m )
+{
+   GET_CURRENT_CONTEXT(ctx);
+   if (!m) return;
+   if (MESA_VERBOSE & VERBOSE_API)
+      _mesa_debug(ctx,
+          "glLoadMatrix(%f %f %f %f, %f %f %f %f, %f %f %f %f, %f %f %f %f\n",
+          m[0], m[4], m[8], m[12],
+          m[1], m[5], m[9], m[13],
+          m[2], m[6], m[10], m[14],
+          m[3], m[7], m[11], m[15]);
+
+   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
+   _math_matrix_loadf( ctx->CurrentStack->Top, m );
+   ctx->NewState |= ctx->CurrentStack->DirtyFlag;
+}
+
+
+/**
+ * Multiply the current matrix with a given matrix.
+ *
+ * \param m matrix.
+ *
+ * \sa glMultMatrixf().
+ *
+ * Flushes the vertices and calls _math_matrix_mul_floats() with the top-most
+ * matrix in the current stack and the given matrix. Marks
+ * __GLcontextRec::NewState with the dirty stack flag.
+ */
+void GLAPIENTRY
+_mesa_MultMatrixf( const GLfloat *m )
+{
+   GET_CURRENT_CONTEXT(ctx);
+   if (!m) return;
+   if (MESA_VERBOSE & VERBOSE_API)
+      _mesa_debug(ctx,
+          "glMultMatrix(%f %f %f %f, %f %f %f %f, %f %f %f %f, %f %f %f %f\n",
+          m[0], m[4], m[8], m[12],
+          m[1], m[5], m[9], m[13],
+          m[2], m[6], m[10], m[14],
+          m[3], m[7], m[11], m[15]);
+   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
+   _math_matrix_mul_floats( ctx->CurrentStack->Top, m );
+   ctx->NewState |= ctx->CurrentStack->DirtyFlag;
+}
+
+
+/**
+ * Multiply the current matrix with a rotation matrix.
+ *
+ * \param angle angle of rotation, in degrees.
+ * \param x rotation vector x coordinate.
+ * \param y rotation vector y coordinate.
+ * \param z rotation vector z coordinate.
+ *
+ * \sa glRotatef().
+ *
+ * Flushes the vertices and calls _math_matrix_rotate() with the top-most
+ * matrix in the current stack and the given parameters. Marks
+ * __GLcontextRec::NewState with the dirty stack flag.
+ */
+void GLAPIENTRY
+_mesa_Rotatef( GLfloat angle, GLfloat x, GLfloat y, GLfloat z )
+{
+   GET_CURRENT_CONTEXT(ctx);
+   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
+   if (angle != 0.0F) {
+      _math_matrix_rotate( ctx->CurrentStack->Top, angle, x, y, z);
+      ctx->NewState |= ctx->CurrentStack->DirtyFlag;
+   }
+}
+
+
+/**
+ * Multiply the current matrix with a general scaling matrix.
+ *
+ * \param x x axis scale factor.
+ * \param y y axis scale factor.
+ * \param z z axis scale factor.
+ *
+ * \sa glScalef().
+ *
+ * Flushes the vertices and calls _math_matrix_scale() with the top-most
+ * matrix in the current stack and the given parameters. Marks
+ * __GLcontextRec::NewState with the dirty stack flag.
+ */
+void GLAPIENTRY
+_mesa_Scalef( GLfloat x, GLfloat y, GLfloat z )
+{
+   GET_CURRENT_CONTEXT(ctx);
+   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
+   _math_matrix_scale( ctx->CurrentStack->Top, x, y, z);
+   ctx->NewState |= ctx->CurrentStack->DirtyFlag;
+}
+
+
+/**
+ * Multiply the current matrix with a translation matrix.
+ *
+ * \param x translation vector x coordinate.
+ * \param y translation vector y coordinate.
+ * \param z translation vector z coordinate.
+ *
+ * \sa glTranslatef().
+ *
+ * Flushes the vertices and calls _math_matrix_translate() with the top-most
+ * matrix in the current stack and the given parameters. Marks
+ * __GLcontextRec::NewState with the dirty stack flag.
+ */
+void GLAPIENTRY
+_mesa_Translatef( GLfloat x, GLfloat y, GLfloat z )
+{
+   GET_CURRENT_CONTEXT(ctx);
+   ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
+   _math_matrix_translate( ctx->CurrentStack->Top, x, y, z);
+   ctx->NewState |= ctx->CurrentStack->DirtyFlag;
+}
+
+ 
+#if _HAVE_FULL_GL
+void GLAPIENTRY
+_mesa_LoadMatrixd( const GLdouble *m )
+{
+   GLint i;
+   GLfloat f[16];
+   if (!m) return;
+   for (i = 0; i < 16; i++)
+      f[i] = (GLfloat) m[i];
+   _mesa_LoadMatrixf(f);
+}
+
+void GLAPIENTRY
+_mesa_MultMatrixd( const GLdouble *m )
+{
+   GLint i;
+   GLfloat f[16];
+   if (!m) return;
+   for (i = 0; i < 16; i++)
+      f[i] = (GLfloat) m[i];
+   _mesa_MultMatrixf( f );
+}
+
+
+void GLAPIENTRY
+_mesa_Rotated( GLdouble angle, GLdouble x, GLdouble y, GLdouble z )
+{
+   _mesa_Rotatef((GLfloat) angle, (GLfloat) x, (GLfloat) y, (GLfloat) z);
+}
+
+
+void GLAPIENTRY
+_mesa_Scaled( GLdouble x, GLdouble y, GLdouble z )
+{
+   _mesa_Scalef((GLfloat) x, (GLfloat) y, (GLfloat) z);
+}
+
+
+void GLAPIENTRY
+_mesa_Translated( GLdouble x, GLdouble y, GLdouble z )
+{
+   _mesa_Translatef((GLfloat) x, (GLfloat) y, (GLfloat) z);
+}
+#endif
+
+
+#if _HAVE_FULL_GL
+void GLAPIENTRY
+_mesa_LoadTransposeMatrixfARB( const GLfloat *m )
+{
+   GLfloat tm[16];
+   if (!m) return;
+   _math_transposef(tm, m);
+   _mesa_LoadMatrixf(tm);
+}
+
+
+void GLAPIENTRY
+_mesa_LoadTransposeMatrixdARB( const GLdouble *m )
+{
+   GLfloat tm[16];
+   if (!m) return;
+   _math_transposefd(tm, m);
+   _mesa_LoadMatrixf(tm);
+}
+
+
+void GLAPIENTRY
+_mesa_MultTransposeMatrixfARB( const GLfloat *m )
+{
+   GLfloat tm[16];
+   if (!m) return;
+   _math_transposef(tm, m);
+   _mesa_MultMatrixf(tm);
+}
+
+
+void GLAPIENTRY
+_mesa_MultTransposeMatrixdARB( const GLdouble *m )
+{
+   GLfloat tm[16];
+   if (!m) return;
+   _math_transposefd(tm, m);
+   _mesa_MultMatrixf(tm);
+}
+#endif
+
+
+
+/**********************************************************************/
+/** \name State management */
+/*@{*/
+
+
+/**
+ * Update the projection matrix stack.
+ *
+ * \param ctx GL context.
+ *
+ * Calls _math_matrix_analyse() with the top-matrix of the projection matrix
+ * stack, and recomputes user clip positions if necessary.
+ * 
+ * \note This routine references __GLcontextRec::Tranform attribute values to
+ * compute userclip positions in clip space, but is only called on
+ * _NEW_PROJECTION.  The _mesa_ClipPlane() function keeps these values up to
+ * date across changes to the __GLcontextRec::Transform attributes.
+ */
+static void
+update_projection( GLcontext *ctx )
+{
+   _math_matrix_analyse( ctx->ProjectionMatrixStack.Top );
+
+#if FEATURE_userclip
+   /* Recompute clip plane positions in clipspace.  This is also done
+    * in _mesa_ClipPlane().
+    */
+   if (ctx->Transform.ClipPlanesEnabled) {
+      GLuint p;
+      for (p = 0; p < ctx->Const.MaxClipPlanes; p++) {
+	 if (ctx->Transform.ClipPlanesEnabled & (1 << p)) {
+	    _mesa_transform_vector( ctx->Transform._ClipUserPlane[p],
+				 ctx->Transform.EyeUserPlane[p],
+				 ctx->ProjectionMatrixStack.Top->inv );
+	 }
+      }
+   }
+#endif
+}
+
+
+/**
+ * Calculate the combined modelview-projection matrix.
+ *
+ * \param ctx GL context.
+ *
+ * Multiplies the top matrices of the projection and model view stacks into
+ * __GLcontextRec::_ModelProjectMatrix via _math_matrix_mul_matrix() and
+ * analyzes the resulting matrix via _math_matrix_analyse().
+ */
+static void
+calculate_model_project_matrix( GLcontext *ctx )
+{
+   _math_matrix_mul_matrix( &ctx->_ModelProjectMatrix,
+                            ctx->ProjectionMatrixStack.Top,
+                            ctx->ModelviewMatrixStack.Top );
+
+   _math_matrix_analyse( &ctx->_ModelProjectMatrix );
+}
+
+
+/**
+ * Updates the combined modelview-projection matrix.
+ *
+ * \param ctx GL context.
+ * \param new_state new state bit mask.
+ *
+ * If there is a new model view matrix then analyzes it. If there is a new
+ * projection matrix, updates it. Finally calls
+ * calculate_model_project_matrix() to recalculate the modelview-projection
+ * matrix.
+ */
+void _mesa_update_modelview_project( GLcontext *ctx, GLuint new_state )
+{
+   if (new_state & _NEW_MODELVIEW) {
+      _math_matrix_analyse( ctx->ModelviewMatrixStack.Top );
+    
+      /* Bring cull position uptodate.
+       */
+      TRANSFORM_POINT3( ctx->Transform.CullObjPos, 
+			ctx->ModelviewMatrixStack.Top->inv,
+			ctx->Transform.CullEyePos );
+   }
+
+
+   if (new_state & _NEW_PROJECTION)
+      update_projection( ctx );
+
+   /* Keep ModelviewProject uptodate always to allow tnl
+    * implementations that go model->clip even when eye is required.
+    */
+   calculate_model_project_matrix(ctx);
+}
+
+/*@}*/
+
+
+/**********************************************************************/
+/** Matrix stack initialization */
+/*@{*/
+
+
+/**
+ * Initialize a matrix stack.
+ *
+ * \param stack matrix stack.
+ * \param maxDepth maximum stack depth.
+ * \param dirtyFlag dirty flag.
+ * 
+ * Allocates an array of \p maxDepth elements for the matrix stack and calls
+ * _math_matrix_ctr() and _math_matrix_alloc_inv() for each element to
+ * initialize it.
+ */
+static void
+init_matrix_stack( struct gl_matrix_stack *stack,
+                   GLuint maxDepth, GLuint dirtyFlag )
+{
+   GLuint i;
+
+   stack->Depth = 0;
+   stack->MaxDepth = maxDepth;
+   stack->DirtyFlag = dirtyFlag;
+   /* The stack */
+   stack->Stack = (GLmatrix *) CALLOC(maxDepth * sizeof(GLmatrix));
+   for (i = 0; i < maxDepth; i++) {
+      _math_matrix_ctr(&stack->Stack[i]);
+      _math_matrix_alloc_inv(&stack->Stack[i]);
+   }
+   stack->Top = stack->Stack;
+}
+
+/**
+ * Free matrix stack.
+ * 
+ * \param stack matrix stack.
+ * 
+ * Calls _math_matrix_dtr() for each element of the matrix stack and
+ * frees the array.
+ */
+static void
+free_matrix_stack( struct gl_matrix_stack *stack )
+{
+   GLuint i;
+   for (i = 0; i < stack->MaxDepth; i++) {
+      _math_matrix_dtr(&stack->Stack[i]);
+   }
+   FREE(stack->Stack);
+   stack->Stack = stack->Top = NULL;
+}
+
+/*@}*/
+
+
+/**********************************************************************/
+/** \name Initialization */
+/*@{*/
+
+
+/**
+ * Initialize the context matrix data.
+ *
+ * \param ctx GL context.
+ *
+ * Initializes each of the matrix stacks and the combined modelview-projection
+ * matrix.
+ */
+void _mesa_init_matrix( GLcontext * ctx )
+{
+   GLint i;
+
+   /* Initialize matrix stacks */
+   init_matrix_stack(&ctx->ModelviewMatrixStack, MAX_MODELVIEW_STACK_DEPTH,
+                     _NEW_MODELVIEW);
+   init_matrix_stack(&ctx->ProjectionMatrixStack, MAX_PROJECTION_STACK_DEPTH,
+                     _NEW_PROJECTION);
+   init_matrix_stack(&ctx->ColorMatrixStack, MAX_COLOR_STACK_DEPTH,
+                     _NEW_COLOR_MATRIX);
+   for (i = 0; i < MAX_TEXTURE_UNITS; i++)
+      init_matrix_stack(&ctx->TextureMatrixStack[i], MAX_TEXTURE_STACK_DEPTH,
+                        _NEW_TEXTURE_MATRIX);
+   for (i = 0; i < MAX_PROGRAM_MATRICES; i++)
+      init_matrix_stack(&ctx->ProgramMatrixStack[i], 
+		        MAX_PROGRAM_MATRIX_STACK_DEPTH, _NEW_TRACK_MATRIX);
+   ctx->CurrentStack = &ctx->ModelviewMatrixStack;
+
+   /* Init combined Modelview*Projection matrix */
+   _math_matrix_ctr( &ctx->_ModelProjectMatrix );
+}
+
+
+/**
+ * Free the context matrix data.
+ * 
+ * \param ctx GL context.
+ *
+ * Frees each of the matrix stacks and the combined modelview-projection
+ * matrix.
+ */
+void _mesa_free_matrix_data( GLcontext *ctx )
+{
+   GLint i;
+
+   free_matrix_stack(&ctx->ModelviewMatrixStack);
+   free_matrix_stack(&ctx->ProjectionMatrixStack);
+   free_matrix_stack(&ctx->ColorMatrixStack);
+   for (i = 0; i < MAX_TEXTURE_UNITS; i++)
+      free_matrix_stack(&ctx->TextureMatrixStack[i]);
+   for (i = 0; i < MAX_PROGRAM_MATRICES; i++)
+      free_matrix_stack(&ctx->ProgramMatrixStack[i]);
+   /* combined Modelview*Projection matrix */
+   _math_matrix_dtr( &ctx->_ModelProjectMatrix );
+
+}
+
+
+/** 
+ * Initialize the context transform attribute group.
+ *
+ * \param ctx GL context.
+ *
+ * \todo Move this to a new file with other 'transform' routines.
+ */
+void _mesa_init_transform( GLcontext *ctx )
+{
+   GLint i;
+
+   /* Transformation group */
+   ctx->Transform.MatrixMode = GL_MODELVIEW;
+   ctx->Transform.Normalize = GL_FALSE;
+   ctx->Transform.RescaleNormals = GL_FALSE;
+   ctx->Transform.RasterPositionUnclipped = GL_FALSE;
+   for (i=0;i<MAX_CLIP_PLANES;i++) {
+      ASSIGN_4V( ctx->Transform.EyeUserPlane[i], 0.0, 0.0, 0.0, 0.0 );
+   }
+   ctx->Transform.ClipPlanesEnabled = 0;
+
+   ASSIGN_4V( ctx->Transform.CullObjPos, 0.0, 0.0, 1.0, 0.0 );
+   ASSIGN_4V( ctx->Transform.CullEyePos, 0.0, 0.0, 1.0, 0.0 );
+}
+
+
+/*@}*/