i965: add software fallback for conformant 3D textures and GL_CLAMP

The i965 hardware cannot do GL_CLAMP behavior on textures; an earlier
commit forced a software fallback if strict conformance was required
(i.e. the INTEL_STRICT_CONFORMANCE environment variable was set) and
2D textures were used, but it was somewhat flawed - it could trigger
the software fallback even if 2D textures weren't enabled, as long
as one texture unit was enabled.

This fixes that, and adds software fallback for GL_CLAMP behavior with
1D and 3D textures.

It also adds support for a particular setting of the INTEL_STRICT_CONFORMANCE
environment variable, which forces software fallbacks to be taken *all*
the time.  This is helpful with debugging.  The value is:
   export INTEL_STRICT_CONFORMANCE=2

1 files changed, 24 insertions, 5 deletions

diff --git a/src/mesa/drivers/dri/i965/brw_draw.c b/src/mesa/drivers/dri/i965/brw_draw.c
index 7ab1ece263..0b64999437 100644
--- a/src/mesa/drivers/dri/i965/brw_draw.c
+++ b/src/mesa/drivers/dri/i965/brw_draw.c
@@ -195,11 +195,15 @@ static GLboolean check_fallbacks( struct brw_context *brw,
    GLuint i;
 
    /* If we don't require strict OpenGL conformance, never 
-    * use fallbacks.
+    * use fallbacks.  If we're forcing fallbacks, always
+    * use fallfacks.
     */
-   if (!brw->intel.strict_conformance)
+   if (brw->intel.conformance_mode == 0)
       return GL_FALSE;
 
+   if (brw->intel.conformance_mode == 2)
+      return GL_TRUE;
+
    if (ctx->Polygon.SmoothFlag) {
       for (i = 0; i < nr_prims; i++)
 	 if (reduced_prim[prim[i].mode] == GL_TRIANGLES) 
@@ -248,10 +252,25 @@ static GLboolean check_fallbacks( struct brw_context *brw,
    {
       int u;
       for (u = 0; u < ctx->Const.MaxTextureCoordUnits; u++) {
-         if (ctx->Texture.Unit[u].Enabled) {
-            if (ctx->Texture.Unit[u].CurrentTex[TEXTURE_2D_INDEX]->WrapS == GL_CLAMP ||
-                ctx->Texture.Unit[u].CurrentTex[TEXTURE_2D_INDEX]->WrapT == GL_CLAMP) {
+         struct gl_texture_unit *texUnit = &ctx->Texture.Unit[u];
+         if (texUnit->Enabled) {
+            if (texUnit->Enabled & TEXTURE_1D_BIT) {
+               if (texUnit->CurrentTex[TEXTURE_1D_INDEX]->WrapS == GL_CLAMP) {
+                   return GL_TRUE;
+               }
+            }
+            if (texUnit->Enabled & TEXTURE_2D_BIT) {
+               if (texUnit->CurrentTex[TEXTURE_2D_INDEX]->WrapS == GL_CLAMP ||
+                   texUnit->CurrentTex[TEXTURE_2D_INDEX]->WrapT == GL_CLAMP) {
+                   return GL_TRUE;
+               }
+            }
+            if (texUnit->Enabled & TEXTURE_3D_BIT) {
+               if (texUnit->CurrentTex[TEXTURE_3D_INDEX]->WrapS == GL_CLAMP ||
+                   texUnit->CurrentTex[TEXTURE_3D_INDEX]->WrapT == GL_CLAMP ||
+                   texUnit->CurrentTex[TEXTURE_3D_INDEX]->WrapR == GL_CLAMP) {
                    return GL_TRUE;
+               }
             }
          }
       }