Refactor "classic" texture environments to be implemented in terms of

ARB_texture_env_combine state.  Add support for
ARB_texture_env_crossbar.  Combiner state is only emitted for operands
that need to be emitted for the combine operation.

1 files changed, 138 insertions, 987 deletions

diff --git a/src/mesa/drivers/dri/i830/i830_texstate.c b/src/mesa/drivers/dri/i830/i830_texstate.c
index 321670a3604..e3d6819d88d 100644
--- a/src/mesa/drivers/dri/i830/i830_texstate.c
+++ b/src/mesa/drivers/dri/i830/i830_texstate.c
@@ -27,12 +27,13 @@ USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 /* $XFree86: xc/lib/GL/mesa/src/drv/i830/i830_texstate.c,v 1.3 2002/12/10 01:26:53 dawes Exp $ */
 
-/*
- * Author:
- *   Jeff Hartmann <[email protected]>
+/**
+ * \file i830_texstate.c
+ * 
+ * Heavily based on the I810 driver, which was written by Keith Whitwell.
  *
- * Heavily based on the I810 driver, which was written by:
- *   Keith Whitwell <[email protected]>
+ * \author Jeff Hartmann <[email protected]>
+ * \author Keith Whitwell <[email protected]>
  */
 
 #include "glheader.h"
@@ -177,857 +178,70 @@ static void i830SetTexImages( i830ContextPtr imesa,
 /* ================================================================
  * Texture combine functions
  */
-static __inline__ GLuint GetTexelOp(GLint unit)
-{
-   switch(unit) {
-    case 0: return TEXBLENDARG_TEXEL0;
-    case 1: return TEXBLENDARG_TEXEL1;
-    case 2: return TEXBLENDARG_TEXEL2;
-    case 3: return TEXBLENDARG_TEXEL3;
-    default: return TEXBLENDARG_TEXEL0;
-   }
-}
-
-static void i830SetBlend_GL1_2(i830ContextPtr imesa, int curTex, 
-			       GLenum envMode, GLenum format)
-{
-   GLuint texel_op = GetTexelOp(curTex);
-
-   if(I830_DEBUG&DEBUG_TEXTURE)
-     fprintf(stderr, "%s %s %s unit (%d) texel_op(0x%x)\n",
-	     __FUNCTION__,
-	     _mesa_lookup_enum_by_nr(format),
-	     _mesa_lookup_enum_by_nr(envMode),
-	     curTex,
-	     texel_op);
-
-   switch(envMode) {
-   case GL_REPLACE:
-      switch(format) {
-      case GL_ALPHA:
-	 imesa->TexBlend[curTex][0] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       DISABLE_TEX_CNTRL_STAGE |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ARG1);
-	 imesa->TexBlend[curTex][1] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ARG1);
-	 imesa->TexBlend[curTex][2] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlend[curTex][3] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       texel_op);
-	 imesa->TexBlendColorPipeNum[curTex] = 0;
-	 imesa->TexBlendWordsUsed[curTex] = 4;
-	 break;
-      case GL_LUMINANCE:
-      case GL_RGB:
-      case GL_YCBCR_MESA:
-	 imesa->TexBlend[curTex][0] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       DISABLE_TEX_CNTRL_STAGE |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ARG1);
-	 imesa->TexBlend[curTex][1] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ARG1);
-	 imesa->TexBlend[curTex][2] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       texel_op);
-	 imesa->TexBlend[curTex][3] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlendColorPipeNum[curTex] = 0;
-	 imesa->TexBlendWordsUsed[curTex] = 4;
-	 break;
-
-      case GL_INTENSITY:
-      case GL_LUMINANCE_ALPHA:
-      case GL_RGBA:
-	 imesa->TexBlend[curTex][0] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       DISABLE_TEX_CNTRL_STAGE |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ARG1);
-	 imesa->TexBlend[curTex][1] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ARG1);
-	 imesa->TexBlend[curTex][2] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       texel_op);
-	 imesa->TexBlend[curTex][3] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       texel_op);
-	 imesa->TexBlendColorPipeNum[curTex] = 0;
-	 imesa->TexBlendWordsUsed[curTex] = 4;
-	 break;
-      default:
-	 /* Always set to passthru if something is funny */
-	 imesa->TexBlend[curTex][0] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       DISABLE_TEX_CNTRL_STAGE |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ARG1);
-	 imesa->TexBlend[curTex][1] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ARG1);
-	 imesa->TexBlend[curTex][2] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlend[curTex][3] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlendColorPipeNum[curTex] = 0;
-	 imesa->TexBlendWordsUsed[curTex] = 4;
-	 break;
-      }
-      break;
-
-   case GL_MODULATE:
-      switch(format) {
-      case GL_ALPHA:
-	 imesa->TexBlend[curTex][0] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       DISABLE_TEX_CNTRL_STAGE |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ARG1);
-	 imesa->TexBlend[curTex][1] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_MODULATE);
-	 imesa->TexBlend[curTex][2] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlend[curTex][3] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       texel_op);
-	 imesa->TexBlend[curTex][4] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG2 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlendColorPipeNum[curTex] = 0;
-	 imesa->TexBlendWordsUsed[curTex] = 5;
-	 break;
-
-      case GL_LUMINANCE:
-      case GL_RGB:
-      case GL_YCBCR_MESA:
-	 imesa->TexBlend[curTex][0] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       DISABLE_TEX_CNTRL_STAGE |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_MODULATE);
-	 imesa->TexBlend[curTex][1] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ARG1);
-	 imesa->TexBlend[curTex][2] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       texel_op);
-	 imesa->TexBlend[curTex][3] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG2 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlend[curTex][4] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlendColorPipeNum[curTex] = 0;
-	 imesa->TexBlendWordsUsed[curTex] = 5;
-	 break;
-
-      case GL_INTENSITY:
-      case GL_LUMINANCE_ALPHA:
-      case GL_RGBA:
-	 imesa->TexBlend[curTex][0] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       DISABLE_TEX_CNTRL_STAGE |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_MODULATE);
-	 imesa->TexBlend[curTex][1] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_MODULATE);
-	 imesa->TexBlend[curTex][2] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       texel_op);
-	 imesa->TexBlend[curTex][3] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG2 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlend[curTex][4] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       texel_op);
-	 imesa->TexBlend[curTex][5] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG2 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlendColorPipeNum[curTex] = 0;
-	 imesa->TexBlendWordsUsed[curTex] = 6;
-	 break;
-      default:
-	 /* Always set to passthru if something is funny */
-	 imesa->TexBlend[curTex][0] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       DISABLE_TEX_CNTRL_STAGE |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ARG1);
-	 imesa->TexBlend[curTex][1] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ARG1);
-	 imesa->TexBlend[curTex][2] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlend[curTex][3] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlendColorPipeNum[curTex] = 0;
-	 imesa->TexBlendWordsUsed[curTex] = 4;
-	 break;
-      }
-      break;
-
-   case GL_DECAL:
-      switch(format) {
-      case GL_RGB:
-      case GL_YCBCR_MESA:
-	 imesa->TexBlend[curTex][0] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       DISABLE_TEX_CNTRL_STAGE |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ARG1);
-	 imesa->TexBlend[curTex][1] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ARG1);
-	 imesa->TexBlend[curTex][2] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       texel_op);
-	 imesa->TexBlend[curTex][3] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlendColorPipeNum[curTex] = 0;
-	 imesa->TexBlendWordsUsed[curTex] = 4;
-	 break;
-
-      case GL_RGBA:
-	 imesa->TexBlend[curTex][0] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       DISABLE_TEX_CNTRL_STAGE |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_BLEND);
-	 imesa->TexBlend[curTex][1] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ARG1);
-	 imesa->TexBlend[curTex][2] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG0 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_REPLICATE_ALPHA |
-				       texel_op);
-	 imesa->TexBlend[curTex][3] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       texel_op);
-	 imesa->TexBlend[curTex][4] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG2 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlend[curTex][5] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlendColorPipeNum[curTex] = 0;
-	 imesa->TexBlendWordsUsed[curTex] = 6;
-	 break;
-      default:
-	 /* Always set to passthru if something is funny */
-	 imesa->TexBlend[curTex][0] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       DISABLE_TEX_CNTRL_STAGE |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ARG1);
-	 imesa->TexBlend[curTex][1] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ARG1);
-	 imesa->TexBlend[curTex][2] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlend[curTex][3] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlendColorPipeNum[curTex] = 0;
-	 imesa->TexBlendWordsUsed[curTex] = 4;
-	 break;
-      }
-      break;
-
-   case GL_BLEND:
-      switch(format) {
-      case GL_ALPHA:
-	 imesa->TexBlend[curTex][0] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       DISABLE_TEX_CNTRL_STAGE |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ARG1);
-	 imesa->TexBlend[curTex][1] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_MODULATE);
-	 imesa->TexBlend[curTex][2] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlend[curTex][3] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       texel_op);
-	 imesa->TexBlend[curTex][4] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG2 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlendColorPipeNum[curTex] = 0;
-	 imesa->TexBlendWordsUsed[curTex] = 5;
-	 break;
-
-      case GL_LUMINANCE:
-      case GL_RGB:
-      case GL_YCBCR_MESA:
-	 imesa->TexBlend[curTex][0] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       DISABLE_TEX_CNTRL_STAGE |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_BLEND);
-	 imesa->TexBlend[curTex][1] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ARG1);
-	 imesa->TexBlend[curTex][2] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG0 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       texel_op);
-	 imesa->TexBlend[curTex][3] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_FACTOR_N);
-	 imesa->TexBlend[curTex][4] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG2 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlend[curTex][5] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlendColorPipeNum[curTex] = 0;
-	 imesa->TexBlendWordsUsed[curTex] = 6;
-	 break;
 
-      case GL_INTENSITY:
-	 imesa->TexBlend[curTex][0] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       DISABLE_TEX_CNTRL_STAGE |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_BLEND);
-	 imesa->TexBlend[curTex][1] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_BLEND);
-	 imesa->TexBlend[curTex][2] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG0 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       texel_op);
-	 imesa->TexBlend[curTex][3] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_FACTOR_N);
-	 imesa->TexBlend[curTex][4] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG2 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlend[curTex][5] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG0 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       texel_op);
-	 imesa->TexBlend[curTex][6] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_FACTOR_N);
-	 imesa->TexBlend[curTex][7] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG2 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlendColorPipeNum[curTex] = 0;
-	 imesa->TexBlendWordsUsed[curTex] = 8;
-	 break;
 
-      case GL_LUMINANCE_ALPHA:
-      case GL_RGBA:
-	 imesa->TexBlend[curTex][0] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       DISABLE_TEX_CNTRL_STAGE |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_BLEND);
-	 imesa->TexBlend[curTex][1] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_MODULATE);
-	 imesa->TexBlend[curTex][2] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG0 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       texel_op);
-	 imesa->TexBlend[curTex][3] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_FACTOR_N);
-	 imesa->TexBlend[curTex][4] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG2 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlend[curTex][5] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       texel_op);
-	 imesa->TexBlend[curTex][6] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG2 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlendColorPipeNum[curTex] = 0;
-	 imesa->TexBlendWordsUsed[curTex] = 7;
-	 break;
-      default:
-	 /* Always set to passthru if something is funny */
-	 imesa->TexBlend[curTex][0] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       DISABLE_TEX_CNTRL_STAGE |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ARG1);
-	 imesa->TexBlend[curTex][1] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ARG1);
-	 imesa->TexBlend[curTex][2] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlend[curTex][3] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlendColorPipeNum[curTex] = 0;
-	 imesa->TexBlendWordsUsed[curTex] = 4;
-	 break;
-      }
-      break;
-
-   case GL_ADD:
-      switch(format) {
-      case GL_ALPHA:
-	 imesa->TexBlend[curTex][0] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       DISABLE_TEX_CNTRL_STAGE |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ARG1);
-	 imesa->TexBlend[curTex][1] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_MODULATE);
-	 imesa->TexBlend[curTex][2] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlend[curTex][3] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       texel_op);
-	 imesa->TexBlend[curTex][4] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG2 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlendColorPipeNum[curTex] = 0;
-	 imesa->TexBlendWordsUsed[curTex] = 5;
-	 break;
-      case GL_LUMINANCE:
-      case GL_RGB:
-      case GL_YCBCR_MESA:
-	 imesa->TexBlend[curTex][0] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       DISABLE_TEX_CNTRL_STAGE |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ADD);
-	 imesa->TexBlend[curTex][1] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ARG1);
-	 imesa->TexBlend[curTex][2] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       texel_op);
-	 imesa->TexBlend[curTex][3] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG2 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlend[curTex][4] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlendColorPipeNum[curTex] = 0;
-	 imesa->TexBlendWordsUsed[curTex] = 5;
-	 break;
-
-      case GL_INTENSITY:
-	 imesa->TexBlend[curTex][0] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       DISABLE_TEX_CNTRL_STAGE |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ADD);
-	 imesa->TexBlend[curTex][1] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ADD);
-	 imesa->TexBlend[curTex][2] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       texel_op);
-	 imesa->TexBlend[curTex][3] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG2 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlend[curTex][4] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       texel_op);
-	 imesa->TexBlend[curTex][5] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG2 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlendColorPipeNum[curTex] = 0;
-	 imesa->TexBlendWordsUsed[curTex] = 6;
-	 break;
-
-      case GL_LUMINANCE_ALPHA:
-      case GL_RGBA:
-	 imesa->TexBlend[curTex][0] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       DISABLE_TEX_CNTRL_STAGE |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ADD);
-	 imesa->TexBlend[curTex][1] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_MODULATE);
-	 imesa->TexBlend[curTex][2] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       texel_op);
-	 imesa->TexBlend[curTex][3] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG2 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlend[curTex][4] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       texel_op);
-	 imesa->TexBlend[curTex][5] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG2 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlendColorPipeNum[curTex] = 0;
-	 imesa->TexBlendWordsUsed[curTex] = 6;
-	 break;
-      default:
-	 /* Always set to passthru if something is funny */
-	 imesa->TexBlend[curTex][0] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       DISABLE_TEX_CNTRL_STAGE |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ARG1);
-	 imesa->TexBlend[curTex][1] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ARG1);
-	 imesa->TexBlend[curTex][2] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlend[curTex][3] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlendColorPipeNum[curTex] = 0;
-	 imesa->TexBlendWordsUsed[curTex] = 4;
-	 break;
-      }
-      break;
-   default:
-	 /* Always set to passthru if something is funny */
-	 imesa->TexBlend[curTex][0] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       DISABLE_TEX_CNTRL_STAGE |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ARG1);
-	 imesa->TexBlend[curTex][1] = (STATE3D_MAP_BLEND_OP_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       ENABLE_TEXOUTPUT_WRT_SEL |
-				       TEXOP_OUTPUT_CURRENT |
-				       TEXOP_SCALE_1X |
-				       TEXOP_MODIFY_PARMS |
-				       TEXBLENDOP_ARG1);
-	 imesa->TexBlend[curTex][2] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_COLOR |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlend[curTex][3] = (STATE3D_MAP_BLEND_ARG_CMD(curTex) |
-				       TEXPIPE_ALPHA |
-				       TEXBLEND_ARG1 |
-				       TEXBLENDARG_MODIFY_PARMS |
-				       TEXBLENDARG_CURRENT);
-	 imesa->TexBlendColorPipeNum[curTex] = 0;
-	 imesa->TexBlendWordsUsed[curTex] = 4;
-	 break;
-   }
-
-   if (I830_DEBUG&DEBUG_TEXTURE)
-      fprintf(stderr, "%s\n", __FUNCTION__);
-}
+/**
+ * Calculate the hardware instuctions to setup the current texture enviromnemt
+ * settings.  Since \c gl_texture_unit::_CurrentCombine is used, both
+ * "classic" texture enviroments and GL_ARB_texture_env_combine type texture
+ * environments are treated identically.
+ *
+ * \todo
+ * This function should return \c GLboolean.  When \c GL_FALSE is returned,
+ * it means that an environment is selected that the hardware cannot do.  This
+ * is the way the Radeon and R200 drivers work.
+ * 
+ * \todo
+ * Looking at i830_3d_regs.h, it seems the i830 can do part of
+ * GL_ATI_texture_env_combine3.  It can handle using \c GL_ONE and
+ * \c GL_ZERO as combine inputs (which the code already supports).  It can
+ * also handle the \c GL_MODULATE_ADD_ATI mode.  Is it worth investigating
+ * partial support for the extension?
+ */
 
-static void i830SetTexEnvCombine(i830ContextPtr imesa,
-				 const struct gl_texture_unit *texUnit, 
-				 GLint unit)
+static void i830UpdateTexEnv( GLcontext *ctx, GLuint unit )
 {
+   i830ContextPtr imesa = I830_CONTEXT(ctx);
+   const struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
+   const GLuint numColorArgs = texUnit->_CurrentCombine->_NumArgsRGB;
+   const GLuint numAlphaArgs = texUnit->_CurrentCombine->_NumArgsA;
+
+   GLboolean need_constant_color = GL_FALSE;
    GLuint blendop;
    GLuint ablendop;
    GLuint args_RGB[3];
    GLuint args_A[3];
-   GLuint texel_op = GetTexelOp(unit);
    GLuint rgb_shift = texUnit->Combine.ScaleShiftRGB;
    GLuint alpha_shift = texUnit->Combine.ScaleShiftA;
    int i;
+   unsigned used;
+   static const GLuint tex_blend_rgb[3] = {
+      TEXPIPE_COLOR | TEXBLEND_ARG1 | TEXBLENDARG_MODIFY_PARMS,
+      TEXPIPE_COLOR | TEXBLEND_ARG2 | TEXBLENDARG_MODIFY_PARMS,
+      TEXPIPE_COLOR | TEXBLEND_ARG0 | TEXBLENDARG_MODIFY_PARMS,
+   };
+   static const GLuint tex_blend_a[3] = {
+      TEXPIPE_ALPHA | TEXBLEND_ARG1 | TEXBLENDARG_MODIFY_PARMS,
+      TEXPIPE_ALPHA | TEXBLEND_ARG2 | TEXBLENDARG_MODIFY_PARMS,
+      TEXPIPE_ALPHA | TEXBLEND_ARG0 | TEXBLENDARG_MODIFY_PARMS,
+   };
+   static const GLuint op_rgb[4] = {
+      0,
+      TEXBLENDARG_INV_ARG,
+      TEXBLENDARG_REPLICATE_ALPHA,
+      TEXBLENDARG_REPLICATE_ALPHA | TEXBLENDARG_INV_ARG,
+   };
+
+
+
+   imesa->TexBlendWordsUsed[unit] = 0;
 
    if(I830_DEBUG&DEBUG_TEXTURE)
-      fprintf(stderr, "%s\n", __FUNCTION__);
+       fprintf(stderr, "[%s:%u] env. mode = %s\n",  __FUNCTION__, __LINE__, 
+	       _mesa_lookup_enum_by_nr(texUnit->EnvMode));
 
-   switch(texUnit->Combine.ModeRGB) {
+
+   switch(texUnit->_CurrentCombine->ModeRGB) {
    case GL_REPLACE: 
       blendop = TEXBLENDOP_ARG1;
       break;
@@ -1066,7 +280,7 @@ static void i830SetTexEnvCombine(i830ContextPtr imesa,
 
    blendop |= (rgb_shift << TEXOP_SCALE_SHIFT);
 
-   switch(texUnit->Combine.ModeA) {
+   switch(texUnit->_CurrentCombine->ModeA) {
    case GL_REPLACE: 
       ablendop = TEXBLENDOP_ARG1;
       break;
@@ -1089,21 +303,32 @@ static void i830SetTexEnvCombine(i830ContextPtr imesa,
       return;
    }
 
-   if ( (texUnit->Combine.ModeRGB == GL_DOT3_RGBA_EXT)
-	|| (texUnit->Combine.ModeRGB == GL_DOT3_RGBA) ) {
+   if ( (texUnit->_CurrentCombine->ModeRGB == GL_DOT3_RGBA_EXT)
+	|| (texUnit->_CurrentCombine->ModeRGB == GL_DOT3_RGBA) ) {
       ablendop = TEXBLENDOP_DOT3;
    }
 
    ablendop |= (alpha_shift << TEXOP_SCALE_SHIFT);
 
    /* Handle RGB args */
-   for(i = 0; i < 3; i++) {
-      switch(texUnit->Combine.SourceRGB[i]) {
+   for( i = 0 ; i < numColorArgs ; i++ ) {
+      const int op = texUnit->_CurrentCombine->OperandRGB[i] - GL_SRC_COLOR;
+
+      assert( (op >= 0) && (op <= 3) );
+      switch(texUnit->_CurrentCombine->SourceRGB[i]) {
       case GL_TEXTURE: 
-	 args_RGB[i] = texel_op;
+	 args_RGB[i] = TEXBLENDARG_TEXEL0 + unit;
+	 break;
+      case GL_TEXTURE0:
+      case GL_TEXTURE1: 
+      case GL_TEXTURE2: 
+      case GL_TEXTURE3:
+	 args_RGB[i] = TEXBLENDARG_TEXEL0
+	     + (texUnit->_CurrentCombine->SourceRGB[i] & 0x03);
 	 break;
       case GL_CONSTANT:
 	 args_RGB[i] = TEXBLENDARG_FACTOR_N; 
+	 need_constant_color = GL_TRUE;
 	 break;
       case GL_PRIMARY_COLOR:
 	 args_RGB[i] = TEXBLENDARG_DIFFUSE;
@@ -1111,38 +336,41 @@ static void i830SetTexEnvCombine(i830ContextPtr imesa,
       case GL_PREVIOUS:
 	 args_RGB[i] = TEXBLENDARG_CURRENT; 
 	 break;
-      default: 
-	 return;
-	 
-      }
-
-      switch(texUnit->Combine.OperandRGB[i]) {
-      case GL_SRC_COLOR: 
-	 args_RGB[i] |= 0;
+      case GL_ONE:
+	 args_RGB[i] = TEXBLENDARG_ONE;
 	 break;
-      case GL_ONE_MINUS_SRC_COLOR: 
-	 args_RGB[i] |= TEXBLENDARG_INV_ARG;
-	 break;
-      case GL_SRC_ALPHA: 
-	 args_RGB[i] |= TEXBLENDARG_REPLICATE_ALPHA;
-	 break;
-      case GL_ONE_MINUS_SRC_ALPHA: 
-	 args_RGB[i] |= (TEXBLENDARG_REPLICATE_ALPHA | 
-			 TEXBLENDARG_INV_ARG);
+      case GL_ZERO:
+	 args_RGB[i] = TEXBLENDARG_ONE | TEXBLENDARG_INV_ARG;
 	 break;
       default: 
 	 return;
       }
+
+      /* Xor is used so that GL_ONE_MINUS_SRC_COLOR with GL_ZERO 
+       * works correctly.
+       */
+      args_RGB[i] ^= op_rgb[op];
    }
 
    /* Handle A args */
-   for(i = 0; i < 3; i++) {
-      switch(texUnit->Combine.SourceA[i]) {
+   for( i = 0 ; i < numAlphaArgs ; i++ ) {
+      const int op = texUnit->_CurrentCombine->OperandA[i] - GL_SRC_ALPHA;
+
+      assert( (op >= 0) && (op <= 1) );
+      switch(texUnit->_CurrentCombine->SourceA[i]) {
       case GL_TEXTURE: 
-	 args_A[i] = texel_op;
+	 args_A[i] = TEXBLENDARG_TEXEL0 + unit;
+	 break;
+      case GL_TEXTURE0:
+      case GL_TEXTURE1: 
+      case GL_TEXTURE2: 
+      case GL_TEXTURE3:
+	 args_A[i] = TEXBLENDARG_TEXEL0 
+	     + (texUnit->_CurrentCombine->SourceA[i] & 0x03);
 	 break;
       case GL_CONSTANT:
 	 args_A[i] = TEXBLENDARG_FACTOR_N; 
+	 need_constant_color = GL_TRUE;
 	 break;
       case GL_PRIMARY_COLOR:
 	 args_A[i] = TEXBLENDARG_DIFFUSE; 
@@ -1150,21 +378,21 @@ static void i830SetTexEnvCombine(i830ContextPtr imesa,
       case GL_PREVIOUS:
 	 args_A[i] = TEXBLENDARG_CURRENT; 
 	 break;
-      default: 
-	 return;
-	 
-      }
-
-      switch(texUnit->Combine.OperandA[i]) {
-      case GL_SRC_ALPHA: 
-	 args_A[i] |= 0;
+      case GL_ONE:
+	 args_A[i] = TEXBLENDARG_ONE;
 	 break;
-      case GL_ONE_MINUS_SRC_ALPHA: 
-	 args_A[i] |= TEXBLENDARG_INV_ARG;
+      case GL_ZERO:
+	 args_A[i] = TEXBLENDARG_ONE | TEXBLENDARG_INV_ARG;
 	 break;
       default: 
 	 return;
       }
+
+      /* We cheat. :) The register values for this are the same as for
+       * RGB.  Xor is used so that GL_ONE_MINUS_SRC_ALPHA with GL_ZERO
+       * works correctly.
+       */
+      args_A[i] ^= op_rgb[op];
    }
 
    /* Native Arg1 == Arg0 in GL_EXT_texture_env_combine spec */
@@ -1179,123 +407,49 @@ static void i830SetTexEnvCombine(i830ContextPtr imesa,
 
    /* Build color pipeline */
 
-   imesa->TexBlend[unit][0] = (STATE3D_MAP_BLEND_OP_CMD(unit) |
-			       TEXPIPE_COLOR |
-			       ENABLE_TEXOUTPUT_WRT_SEL |
-			       TEXOP_OUTPUT_CURRENT |
-			       DISABLE_TEX_CNTRL_STAGE |
-			       TEXOP_MODIFY_PARMS |
-			       blendop);
-   imesa->TexBlend[unit][1] = (STATE3D_MAP_BLEND_ARG_CMD(unit) |
-			       TEXPIPE_COLOR |
-			       TEXBLEND_ARG1 |
-			       TEXBLENDARG_MODIFY_PARMS |
-			       args_RGB[0]);
-   imesa->TexBlend[unit][2] = (STATE3D_MAP_BLEND_ARG_CMD(unit) |
-			       TEXPIPE_COLOR |
-			       TEXBLEND_ARG2 |
-			       TEXBLENDARG_MODIFY_PARMS |
-			       args_RGB[1]);
-   imesa->TexBlend[unit][3] = (STATE3D_MAP_BLEND_ARG_CMD(unit) |
-			       TEXPIPE_COLOR |
-			       TEXBLEND_ARG0 |
-			       TEXBLENDARG_MODIFY_PARMS |
-			       args_RGB[2]);
+   used = 0;
+   imesa->TexBlend[unit][used++] = (STATE3D_MAP_BLEND_OP_CMD(unit) |
+				    TEXPIPE_COLOR |
+				    ENABLE_TEXOUTPUT_WRT_SEL |
+				    TEXOP_OUTPUT_CURRENT |
+				    DISABLE_TEX_CNTRL_STAGE |
+				    TEXOP_MODIFY_PARMS |
+				    blendop);
+
+   imesa->TexBlend[unit][used++] = (STATE3D_MAP_BLEND_OP_CMD(unit) |
+				    TEXPIPE_ALPHA |
+				    ENABLE_TEXOUTPUT_WRT_SEL |
+				    TEXOP_OUTPUT_CURRENT |
+				    TEXOP_MODIFY_PARMS |
+				    ablendop);
+
+   for ( i = 0 ; i < numColorArgs ; i++ ) {
+      imesa->TexBlend[unit][used++] = (STATE3D_MAP_BLEND_ARG_CMD(unit) |
+				       tex_blend_rgb[i] |
+				       args_RGB[i]);
+   }
+
+   for ( i = 0 ; i < numAlphaArgs ; i++ ) {
+      imesa->TexBlend[unit][used++] = (STATE3D_MAP_BLEND_ARG_CMD(unit) |
+				       tex_blend_a[i] |
+				       args_A[i]);
+   }
 
-   /* Build Alpha pipeline */
-   imesa->TexBlend[unit][4] = (STATE3D_MAP_BLEND_OP_CMD(unit) |
-			       TEXPIPE_ALPHA |
-			       ENABLE_TEXOUTPUT_WRT_SEL |
-			       TEXOP_OUTPUT_CURRENT |
-			       TEXOP_MODIFY_PARMS |
-			       ablendop);
-   imesa->TexBlend[unit][5] = (STATE3D_MAP_BLEND_ARG_CMD(unit) |
-			       TEXPIPE_ALPHA |
-			       TEXBLEND_ARG1 |
-			       TEXBLENDARG_MODIFY_PARMS |
-			       args_A[0]);
-   imesa->TexBlend[unit][6] = (STATE3D_MAP_BLEND_ARG_CMD(unit) |
-			       TEXPIPE_ALPHA |
-			       TEXBLEND_ARG2 |
-			       TEXBLENDARG_MODIFY_PARMS |
-			       args_A[1]);
-   imesa->TexBlend[unit][7] = (STATE3D_MAP_BLEND_ARG_CMD(unit) |
-			       TEXPIPE_ALPHA |
-			       TEXBLEND_ARG0 |
-			       TEXBLENDARG_MODIFY_PARMS |
-			       args_A[2]);
 
-   {
+   if ( need_constant_color ) {
       GLubyte r, g, b, a;
-      GLfloat *fc = texUnit->EnvColor;
+      const GLfloat * const fc = texUnit->EnvColor;
 
       FLOAT_COLOR_TO_UBYTE_COLOR(r, fc[RCOMP]);
       FLOAT_COLOR_TO_UBYTE_COLOR(g, fc[GCOMP]);
       FLOAT_COLOR_TO_UBYTE_COLOR(b, fc[BCOMP]);
       FLOAT_COLOR_TO_UBYTE_COLOR(a, fc[ACOMP]);
 
-      imesa->TexBlend[unit][8] = STATE3D_COLOR_FACTOR_CMD(unit);
-      imesa->TexBlend[unit][9] =  ((a << 24) |
-				   (r << 16) |
-				   (g << 8) |
-				   b);
-   }
-   imesa->TexBlendWordsUsed[unit] = 10;
-}
-
-
-
-
-static void i830UpdateTexEnv( GLcontext *ctx, GLuint unit )
-{
-   i830ContextPtr imesa = I830_CONTEXT(ctx);
-   const struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
-   const struct gl_texture_object *tObj = texUnit->_Current;
-   i830TextureObjectPtr t = (i830TextureObjectPtr)tObj->DriverData;
-   GLuint col;
-
-   imesa->TexBlendWordsUsed[unit] = 0;
-
-   if (0) fprintf(stderr, "i830UpdateTexEnv called : %s\n",
-		  _mesa_lookup_enum_by_nr(texUnit->EnvMode));
-
-   if(texUnit->EnvMode == GL_COMBINE) {
-      i830SetTexEnvCombine(imesa,
-			   texUnit,
-			   unit);
-   } else {
-      i830SetBlend_GL1_2(imesa,
-			 unit,
-			 texUnit->EnvMode,
-			 t->image[0][0].internalFormat);
-
-      /* add blend color */
-      {
-	 GLubyte r, g, b, a;
-	 GLfloat *fc = texUnit->EnvColor;
-
-	 FLOAT_COLOR_TO_UBYTE_COLOR(r, fc[RCOMP]);
-	 FLOAT_COLOR_TO_UBYTE_COLOR(g, fc[GCOMP]);
-	 FLOAT_COLOR_TO_UBYTE_COLOR(b, fc[BCOMP]);
-	 FLOAT_COLOR_TO_UBYTE_COLOR(a, fc[ACOMP]);
-
-	 col = ((a << 24) |
-		(r << 16) |
-		(g << 8) |
-		b);
-      }       
-
-      {
-	 int i;
-
-	 i = imesa->TexBlendWordsUsed[unit];
-	 imesa->TexBlend[unit][i++] = STATE3D_COLOR_FACTOR_CMD(unit);	  
-	 imesa->TexBlend[unit][i++] = col;
-
-	 imesa->TexBlendWordsUsed[unit] = i;
-      }
+      imesa->TexBlend[unit][used++] = STATE3D_COLOR_FACTOR_CMD(unit);
+      imesa->TexBlend[unit][used++] = ((a << 24) | (r << 16) | (g << 8) | b);
    }
 
+   imesa->TexBlendWordsUsed[unit] = used;
    I830_STATECHANGE( imesa, I830_UPLOAD_TEXBLEND_N(unit) );
 }
 
@@ -1529,6 +683,3 @@ void i830UpdateTextureState( GLcontext *ctx )
       imesa->TexBlend[0][pipe_num] |= TEXOP_LAST_STAGE;
    }
 }
-
-
-