gallium: rework handling of sprite_coord_enable state

Implement the pipe_rasterizer_state::sprite_coord_enable field
in the draw module (and softpipe) according to what's specified
in the documentation.

The draw module can now add any number of extra vertex attributes
to a post-transformed vertex and generate texcoords for those
attributes per sprite_coord_enable.  Auto-generated texcoords
for sprites only worked for one texcoord unit before.

The frag shader gl_PointCoord input is now implemented like any
other generic/texcoord attribute.

The draw module now needs to be informed about fragment shaders
since we need to look at the fragment shader's inputs to know
which ones need auto-generated texcoords.

Only softpipe has been updated so far.

1 files changed, 14 insertions, 0 deletions

diff --git a/src/mesa/state_tracker/st_atom_rasterizer.c b/src/mesa/state_tracker/st_atom_rasterizer.c
index 2599bd5ca0..0fe333ae8a 100644
--- a/src/mesa/state_tracker/st_atom_rasterizer.c
+++ b/src/mesa/state_tracker/st_atom_rasterizer.c
@@ -60,6 +60,7 @@ static void update_raster_state( struct st_context *st )
    GLcontext *ctx = st->ctx;
    struct pipe_rasterizer_state *raster = &st->state.rasterizer;
    const struct gl_vertex_program *vertProg = ctx->VertexProgram._Current;
+   const struct gl_fragment_program *fragProg = ctx->FragmentProgram._Current;
    uint i;
 
    memset(raster, 0, sizeof(*raster));
@@ -175,17 +176,30 @@ static void update_raster_state( struct st_context *st )
    if (!ctx->Point.PointSprite && ctx->Point.SmoothFlag)
       raster->point_smooth = 1;
 
+   /* _NEW_POINT | _NEW_PROGRAM
+    */
    if (ctx->Point.PointSprite) {
+      /* origin */
       if ((ctx->Point.SpriteOrigin == GL_UPPER_LEFT) ^
           (st_fb_orientation(ctx->DrawBuffer) == Y_0_BOTTOM))
          raster->sprite_coord_mode = PIPE_SPRITE_COORD_UPPER_LEFT;
       else 
          raster->sprite_coord_mode = PIPE_SPRITE_COORD_LOWER_LEFT;
+
+      /* Coord replacement flags.  If bit 'k' is set that means
+       * that we need to replace GENERIC[k] attrib with an automatically
+       * computed texture coord.
+       */
       for (i = 0; i < MAX_TEXTURE_COORD_UNITS; i++) {
          if (ctx->Point.CoordReplace[i]) {
             raster->sprite_coord_enable |= 1 << i;
          }
       }
+      if (fragProg->Base.InputsRead & FRAG_BIT_PNTC) {
+         raster->sprite_coord_enable |=
+            1 << (FRAG_ATTRIB_PNTC - FRAG_ATTRIB_TEX0);
+      }
+
       raster->point_quad_rasterization = 1;
    }