gallium: add TGSI_SEMANTIC_TEXCOORD,PCOORD v3

This makes it possible to identify gl_TexCoord and gl_PointCoord
for drivers where sprite coordinate replacement is restricted.

The new PIPE_CAP_TGSI_TEXCOORD decides whether these varyings
should be hidden behind the GENERIC semantic or not.

With this patch only nvc0 and nv30 will request that they be used.

v2: introduce a CAP so other drivers don't have to bother with
the new semantic

v3: adapt to introduction gl_varying_slot enum

1 files changed, 6 insertions, 1 deletions

diff --git a/src/gallium/drivers/nv30/nvfx_vertprog.c b/src/gallium/drivers/nv30/nvfx_vertprog.c
index 74dba38001c..b73d4184045 100644
--- a/src/gallium/drivers/nv30/nvfx_vertprog.c
+++ b/src/gallium/drivers/nv30/nvfx_vertprog.c
@@ -819,6 +819,7 @@ nvfx_vertprog_parse_decl_output(struct nv30_context *nv30, struct nvfx_vpc *vpc,
 {
    unsigned num_texcoords = nv30->is_nv4x ? 10 : 8;
    unsigned idx = fdec->Range.First;
+   unsigned semantic_index = fdec->Semantic.Index;
    int hw = 0, i;
 
    switch (fdec->Semantic.Name) {
@@ -860,8 +861,12 @@ nvfx_vertprog_parse_decl_output(struct nv30_context *nv30, struct nvfx_vpc *vpc,
       hw = NVFX_VP(INST_DEST_PSZ);
       break;
    case TGSI_SEMANTIC_GENERIC:
+      /* this is really an identifier for VP/FP linkage */
+      semantic_index += 8;
+      /* fall through */
+   case TGSI_SEMANTIC_TEXCOORD:
       for (i = 0; i < num_texcoords; i++) {
-         if (vpc->vp->texcoord[i] == fdec->Semantic.Index) {
+         if (vpc->vp->texcoord[i] == semantic_index) {
             hw = NVFX_VP(INST_DEST_TC(i));
             break;
          }