t_vb_texgen.c

Mesa is an open-source implementation of the OpenGL specification - a system for rendering interacti

   GLvector4f *in = VB->AttribPtr[VERT_ATTRIB_TEX0 + unit];
   GLvector4f *out = &store->texcoord[unit];
   GLfloat (*texcoord)[4] = (GLfloat (*)[4]) out->start;
   GLuint count = VB->Count;
   GLuint i;
   GLfloat (*f)[3] = store->tmp_f;
   GLfloat *m = store->tmp_m;

   (build_m_tab[VB->EyePtr->size])( store->tmp_f,
				    store->tmp_m,
				    VB->AttribPtr[_TNL_ATTRIB_NORMAL],
				    VB->EyePtr );

   out->size = MAX2(in->size,2);

   for (i=0;i<count;i++) {
      texcoord[i][0] = f[i][0] * m[i] + 0.5F;
      texcoord[i][1] = f[i][1] * m[i] + 0.5F;
   }

   out->count = count;
   out->flags |= (in->flags & VEC_SIZE_FLAGS) | VEC_SIZE_2;
   if (in->size > 2)
      _mesa_copy_tab[all_bits[in->size] & ~0x3]( out, in );
}



static void texgen( GLcontext *ctx,
		    struct texgen_stage_data *store,
		    GLuint unit )
{
   TNLcontext *tnl = TNL_CONTEXT(ctx);
   struct vertex_buffer *VB = &tnl->vb;
   GLvector4f *in = VB->AttribPtr[VERT_ATTRIB_TEX0 + unit];
   GLvector4f *out = &store->texcoord[unit];
   const struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
   const GLvector4f *obj = VB->ObjPtr;
   const GLvector4f *eye = VB->EyePtr;
   const GLvector4f *normal = VB->AttribPtr[_TNL_ATTRIB_NORMAL];
   const GLfloat *m = store->tmp_m;
   const GLuint count = VB->Count;
   GLfloat (*texcoord)[4] = (GLfloat (*)[4])out->data;
   GLfloat (*f)[3] = store->tmp_f;
   GLuint copy;

   if (texUnit->_GenFlags & TEXGEN_NEED_M) {
      build_m_tab[eye->size]( store->tmp_f, store->tmp_m, normal, eye );
   } else if (texUnit->_GenFlags & TEXGEN_NEED_F) {
      build_f_tab[eye->size]( (GLfloat *)store->tmp_f, 3, normal, eye );
   }


   out->size = MAX2(in->size, store->TexgenSize[unit]);
   out->flags |= (in->flags & VEC_SIZE_FLAGS) | texUnit->TexGenEnabled;
   out->count = count;

   copy = (all_bits[in->size] & ~texUnit->TexGenEnabled);
   if (copy)
      _mesa_copy_tab[copy]( out, in );

   if (texUnit->TexGenEnabled & S_BIT) {
      GLuint i;
      switch (texUnit->GenModeS) {
      case GL_OBJECT_LINEAR:
	 _mesa_dotprod_tab[obj->size]( (GLfloat *)out->data,
				       sizeof(out->data[0]), obj,
				       texUnit->ObjectPlaneS );
	 break;
      case GL_EYE_LINEAR:
	 _mesa_dotprod_tab[eye->size]( (GLfloat *)out->data,
				       sizeof(out->data[0]), eye,
				       texUnit->EyePlaneS );
	 break;
      case GL_SPHERE_MAP:
         for (i = 0; i < count; i++)
            texcoord[i][0] = f[i][0] * m[i] + 0.5F;
	 break;
      case GL_REFLECTION_MAP_NV:
	 for (i=0;i<count;i++)
	     texcoord[i][0] = f[i][0];
	 break;
      case GL_NORMAL_MAP_NV: {
	 const GLfloat *norm = normal->start;
	 for (i=0;i<count;i++, STRIDE_F(norm, normal->stride)) {
	     texcoord[i][0] = norm[0];
	 }
	 break;
      }
      default:
	 _mesa_problem(ctx, "Bad S texgen");
      }
   }

   if (texUnit->TexGenEnabled & T_BIT) {
      GLuint i;
      switch (texUnit->GenModeT) {
      case GL_OBJECT_LINEAR:
	 _mesa_dotprod_tab[obj->size]( &(out->data[0][1]),
				       sizeof(out->data[0]), obj,
				       texUnit->ObjectPlaneT );
	 break;
      case GL_EYE_LINEAR:
	 _mesa_dotprod_tab[eye->size]( &(out->data[0][1]),
				       sizeof(out->data[0]), eye,
				       texUnit->EyePlaneT );
	 break;
      case GL_SPHERE_MAP:
         for (i = 0; i < count; i++)
            texcoord[i][1] = f[i][1] * m[i] + 0.5F;
	 break;
      case GL_REFLECTION_MAP_NV:
	 for (i=0;i<count;i++)
	     texcoord[i][1] = f[i][1];
	 break;
      case GL_NORMAL_MAP_NV: {
	 const GLfloat *norm = normal->start;
	 for (i=0;i<count;i++, STRIDE_F(norm, normal->stride)) {
	     texcoord[i][1] = norm[1];
	 }
	 break;
      }
      default:
	 _mesa_problem(ctx, "Bad T texgen");
      }
   }

   if (texUnit->TexGenEnabled & R_BIT) {
      GLuint i;
      switch (texUnit->GenModeR) {
      case GL_OBJECT_LINEAR:
	 _mesa_dotprod_tab[obj->size]( &(out->data[0][2]),
				       sizeof(out->data[0]), obj,
				       texUnit->ObjectPlaneR );
	 break;
      case GL_EYE_LINEAR:
	 _mesa_dotprod_tab[eye->size]( &(out->data[0][2]),
				       sizeof(out->data[0]), eye,
				       texUnit->EyePlaneR );
	 break;
      case GL_REFLECTION_MAP_NV:
	 for (i=0;i<count;i++)
	     texcoord[i][2] = f[i][2];
	 break;
      case GL_NORMAL_MAP_NV: {
	 const GLfloat *norm = normal->start;
	 for (i=0;i<count;i++,STRIDE_F(norm, normal->stride)) {
	     texcoord[i][2] = norm[2];
	 }
	 break;
      }
      default:
	 _mesa_problem(ctx, "Bad R texgen");
      }
   }

   if (texUnit->TexGenEnabled & Q_BIT) {
      switch (texUnit->GenModeQ) {
      case GL_OBJECT_LINEAR:
	 _mesa_dotprod_tab[obj->size]( &(out->data[0][3]),
				       sizeof(out->data[0]), obj,
				       texUnit->ObjectPlaneQ );
	 break;
      case GL_EYE_LINEAR:
	 _mesa_dotprod_tab[eye->size]( &(out->data[0][3]),
				       sizeof(out->data[0]), eye,
				       texUnit->EyePlaneQ );
	 break;
      default:
	 _mesa_problem(ctx, "Bad Q texgen");
      }
   }
}




static GLboolean run_texgen_stage( GLcontext *ctx,
				   struct tnl_pipeline_stage *stage )
{
   struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb;
   struct texgen_stage_data *store = TEXGEN_STAGE_DATA(stage);
   GLuint i;

   if (!ctx->Texture._TexGenEnabled || ctx->VertexProgram._Current) 
      return GL_TRUE;

   for (i = 0 ; i < ctx->Const.MaxTextureCoordUnits ; i++) {
      struct gl_texture_unit *texUnit = &ctx->Texture.Unit[i];

      if (texUnit->TexGenEnabled) {

	 store->TexgenFunc[i]( ctx, store, i );

         VB->TexCoordPtr[i] =
         VB->AttribPtr[VERT_ATTRIB_TEX0 + i] = &store->texcoord[i];
      }
   }

   return GL_TRUE;
}


static void validate_texgen_stage( GLcontext *ctx,
				   struct tnl_pipeline_stage *stage )
{
   struct texgen_stage_data *store = TEXGEN_STAGE_DATA(stage);
   GLuint i;

   if (!ctx->Texture._TexGenEnabled || ctx->VertexProgram._Current) 
      return;

   for (i = 0 ; i < ctx->Const.MaxTextureCoordUnits ; i++) {
      struct gl_texture_unit *texUnit = &ctx->Texture.Unit[i];

      if (texUnit->TexGenEnabled) {
	 GLuint sz;

	 if (texUnit->TexGenEnabled & Q_BIT)
	    sz = 4;
	 else if (texUnit->TexGenEnabled & R_BIT)
	    sz = 3;
	 else if (texUnit->TexGenEnabled & T_BIT)
	    sz = 2;
	 else
	    sz = 1;

	 store->TexgenSize[i] = sz;
	 store->TexgenFunc[i] = texgen; /* general solution */

         /* look for special texgen cases */
	 if (texUnit->TexGenEnabled == (S_BIT|T_BIT|R_BIT)) {
	    if (texUnit->_GenFlags == TEXGEN_REFLECTION_MAP_NV) {
	       store->TexgenFunc[i] = texgen_reflection_map_nv;
	    }
	    else if (texUnit->_GenFlags == TEXGEN_NORMAL_MAP_NV) {
	       store->TexgenFunc[i] = texgen_normal_map_nv;
	    }
	 }
	 else if (texUnit->TexGenEnabled == (S_BIT|T_BIT) &&
		  texUnit->_GenFlags == TEXGEN_SPHERE_MAP) {
	    store->TexgenFunc[i] = texgen_sphere_map;
	 }
      }
   }
}





/* Called the first time stage->run() is invoked.
 */
static GLboolean alloc_texgen_data( GLcontext *ctx,
				    struct tnl_pipeline_stage *stage )
{
   struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb;
   struct texgen_stage_data *store;
   GLuint i;

   stage->privatePtr = CALLOC(sizeof(*store));
   store = TEXGEN_STAGE_DATA(stage);
   if (!store)
      return GL_FALSE;

   for (i = 0 ; i < ctx->Const.MaxTextureCoordUnits ; i++)
      _mesa_vector4f_alloc( &store->texcoord[i], 0, VB->Size, 32 );

   store->tmp_f = (GLfloat (*)[3]) MALLOC(VB->Size * sizeof(GLfloat) * 3);
   store->tmp_m = (GLfloat *) MALLOC(VB->Size * sizeof(GLfloat));

   return GL_TRUE;
}


static void free_texgen_data( struct tnl_pipeline_stage *stage )

{
   struct texgen_stage_data *store = TEXGEN_STAGE_DATA(stage);
   GLuint i;

   if (store) {
      for (i = 0 ; i < MAX_TEXTURE_COORD_UNITS ; i++)
	 if (store->texcoord[i].data)
	    _mesa_vector4f_free( &store->texcoord[i] );


      if (store->tmp_f) FREE( store->tmp_f );
      if (store->tmp_m) FREE( store->tmp_m );
      FREE( store );
      stage->privatePtr = NULL;
   }
}



const struct tnl_pipeline_stage _tnl_texgen_stage =
{
   "texgen",			/* name */
   NULL,			/* private data */
   alloc_texgen_data,		/* destructor */
   free_texgen_data,		/* destructor */
   validate_texgen_stage,		/* check */
   run_texgen_stage		/* run -- initially set to alloc data */
};