nvfx: properly return fogcoord.w == 1

Hardware sets it to 0, so we add an ADD to put an 1 there if the
application really wants the alpha channel.

diff --git a/src/gallium/drivers/nvfx/nvfx_fragprog.c b/src/gallium/drivers/nvfx/nvfx_fragprog.c
index 86df7f004963e773334988a063bfd80d899de65e..23121ebe1ea563543da252488477b155e6572540 100644 (file)
--- a/src/gallium/drivers/nvfx/nvfx_fragprog.c
+++ b/src/gallium/drivers/nvfx/nvfx_fragprog.c
@@ -493,7 +493,21 @@ nvfx_fragprog_parse_instruction(struct nvfx_context* nvfx, struct nvfx_fpc *fpc,
 
                switch (fsrc->Register.File) {
                case TGSI_FILE_INPUT:
-                       if (ai == -1 || ai == fsrc->Register.Index) {
+                       if(fpc->pfp->info.input_semantic_name[fsrc->Register.Index] == TGSI_SEMANTIC_FOG && (0
+                                       || fsrc->Register.SwizzleX == PIPE_SWIZZLE_ALPHA
+                                       || fsrc->Register.SwizzleY == PIPE_SWIZZLE_ALPHA
+                                       || fsrc->Register.SwizzleZ == PIPE_SWIZZLE_ALPHA
+                                       || fsrc->Register.SwizzleW == PIPE_SWIZZLE_ALPHA
+                                       )) {
+                               /* hardware puts 0 in fogcoord.w, but GL/Gallium want 1 there */
+                               struct nvfx_src addend = nvfx_src(nvfx_fp_imm(fpc, 0, 0, 0, 1));
+                               addend.swz[0] = fsrc->Register.SwizzleX;
+                               addend.swz[1] = fsrc->Register.SwizzleY;
+                               addend.swz[2] = fsrc->Register.SwizzleZ;
+                               addend.swz[3] = fsrc->Register.SwizzleW;
+                               src[i] = nvfx_src(temp(fpc));
+                               nvfx_fp_emit(fpc, arith(0, ADD, src[i].reg, NVFX_FP_MASK_ALL, tgsi_src(fpc, fsrc), addend, none));
+                       } else if (ai == -1 || ai == fsrc->Register.Index) {
                                ai = fsrc->Register.Index;
                                src[i] = tgsi_src(fpc, fsrc);
                        } else {