text: /* $Id: t_vb_texmat.c,v 1.10 2002/10/29 20:29:04 brianp Exp $ */
  
  /*
   * Mesa 3-D graphics library
   * Version:  3.5
   *
   * Copyright (C) 1999-2001  Brian Paul   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.
   *
   * Authors:
   *    Keith Whitwell <keith@tungstengraphics.com>
   */
  
  
  #include "glheader.h"
  #include "colormac.h"
  #include "context.h"
  #include "macros.h"
  #include "imports.h"
  #include "mmath.h"
  #include "mtypes.h"
  
  #include "math/m_xform.h"
  
  #include "t_context.h"
  #include "t_pipeline.h"
  
  /* Is there any real benefit seperating texmat from texgen?  It means
   * we need two lots of intermediate storage.  Any changes to
   * _NEW_TEXTURE will invalidate both sets -- it's only on changes to
   * *only* _NEW_TEXTURE_MATRIX that texgen survives but texmat doesn't.
   *
   * However, the seperation of this code from the complex texgen stuff
   * is very appealing.
   */
  struct texmat_stage_data {
     GLvector4f texcoord[MAX_TEXTURE_UNITS];
  };
  
  #define TEXMAT_STAGE_DATA(stage) ((struct texmat_stage_data *)stage->privatePtr)
  
  static void check_texmat( GLcontext *ctx, struct gl_pipeline_stage *stage )
  {
     GLuint i;
     stage->active = 0;
  
     if (ctx->Texture._TexMatEnabled && !ctx->VertexProgram.Enabled) {
        GLuint flags = 0;
  
        for (i = 0 ; i < ctx->Const.MaxTextureUnits ; i++)
  	 if (ctx->Texture._TexMatEnabled & ENABLE_TEXMAT(i))
  	    flags |= VERT_BIT_TEX(i);
  
        stage->active = 1;
        stage->inputs = flags;
        stage->outputs = flags;
     }
  }
  
  static GLboolean run_texmat_stage( GLcontext *ctx,
  				   struct gl_pipeline_stage *stage )
  {
     struct texmat_stage_data *store = TEXMAT_STAGE_DATA(stage);
     struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb;
     GLuint i;
  
     /* ENABLE_TEXMAT implies that the texture matrix is not the
      * identity, so we don't have to check that here.
      */
     for (i = 0 ; i < ctx->Const.MaxTextureUnits ; i++)
        if (ctx->Texture._TexMatEnabled & ENABLE_TEXMAT(i)) {
  	 if (stage->changed_inputs & VERT_BIT_TEX(i))
  	    (void) TransformRaw( &store->texcoord[i],
                                   ctx->TextureMatrixStack[i].Top,
  				 VB->TexCoordPtr[i]);
  
  	 VB->TexCoordPtr[i] = &store->texcoord[i];
        }
     return GL_TRUE;
  }
  
  
  /* Called the first time stage->run() is invoked.
   */
  static GLboolean alloc_texmat_data( GLcontext *ctx,
  				    struct gl_pipeline_stage *stage )
  {
     struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb;
     struct texmat_stage_data *store;
     GLuint i;
  
     stage->privatePtr = CALLOC(sizeof(*store));
     store = TEXMAT_STAGE_DATA(stage);
     if (!store)
        return GL_FALSE;
  
     for (i = 0 ; i < ctx->Const.MaxTextureUnits ; i++)
        _mesa_vector4f_alloc( &store->texcoord[i], 0, VB->Size, 32 );
  
     /* Now run the stage.
      */
     stage->run = run_texmat_stage;
     return stage->run( ctx, stage );
  }
  
  
  static void free_texmat_data( struct gl_pipeline_stage *stage )
  {
     struct texmat_stage_data *store = TEXMAT_STAGE_DATA(stage);
     GLuint i;
  
     if (store) {
        for (i = 0 ; i < MAX_TEXTURE_UNITS ; i++)
  	 if (store->texcoord[i].data)
  	    _mesa_vector4f_free( &store->texcoord[i] );
        FREE( store );
        stage->privatePtr = 0;
     }
  }
  
  
  
  const struct gl_pipeline_stage _tnl_texture_transform_stage =
  {
     "texture transform",			/* name */
     _NEW_TEXTURE|_NEW_TEXTURE_MATRIX,	/* check_state */
     _NEW_TEXTURE|_NEW_TEXTURE_MATRIX,	/* run_state */
     GL_FALSE,				/* active? */
     0,					/* inputs */
     0,					/* outputs */
     0,					/* changed_inputs */
     NULL,				/* private data */
     free_texmat_data,			/* destructor */
     check_texmat,			/* check */
     alloc_texmat_data,			/* run -- initially set to init */
  };
  