Mesa (master): r300-gallium: Prevent assert when fogcoords are present.

[Corbin Simpson]

Module: Mesa
Branch: master
Commit: d67fb5ea1d93db3f64720994017c312a04867eea
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=d67fb5ea1d93db3f64720994017c312a04867eea

Author: Corbin Simpson <MostAwesomeDude at gmail.com>
Date:   Wed May 20 15:02:45 2009 -0700

r300-gallium: Prevent assert when fogcoords are present.

Seems like this file is the source of all bad logic. (Pun intended.)

---

 src/gallium/drivers/r300/r300_state_derived.c |   18 +++++++++++++-----
 src/gallium/drivers/r300/r300_state_shader.c  |    1 +
 2 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/src/gallium/drivers/r300/r300_state_derived.c b/src/gallium/drivers/r300/r300_state_derived.c
index caa5f3b..7ae339c 100644
--- a/src/gallium/drivers/r300/r300_state_derived.c
+++ b/src/gallium/drivers/r300/r300_state_derived.c
@@ -64,6 +64,7 @@ static void r300_vs_tab_routes(struct r300_context* r300,
                     break;
                 case TGSI_SEMANTIC_FOG:
                     fog = TRUE;
+                    /* Fall through */
                 case TGSI_SEMANTIC_GENERIC:
                     texs++;
                     break;
@@ -103,6 +104,9 @@ static void r300_vs_tab_routes(struct r300_context* r300,
         }
     }
 
+    /* XXX magic */
+    assert(texs <= 8);
+
     /* Do the actual vertex_info setup.
      *
      * vertex_info has four uints of hardware-specific data in it.
@@ -140,17 +144,21 @@ static void r300_vs_tab_routes(struct r300_context* r300,
         vinfo->hwfmt[2] |= (R300_VAP_OUTPUT_VTX_FMT_0__COLOR_0_PRESENT << i);
     }
 
-    for (i = 0; i < texs; i++) {
+    /* Init i right here, increment it if fog is enabled.
+     * This gets around a double-increment problem. */
+    i = 0;
+
+    if (fog) {
+        i++;
         draw_emit_vertex_attr(vinfo, EMIT_4F, INTERP_PERSPECTIVE,
-            draw_find_vs_output(r300->draw, TGSI_SEMANTIC_GENERIC, i));
+            draw_find_vs_output(r300->draw, TGSI_SEMANTIC_FOG, 0));
         vinfo->hwfmt[1] |= (R300_INPUT_CNTL_TC0 << i);
         vinfo->hwfmt[3] |= (4 << (3 * i));
     }
 
-    if (fog) {
-        i++;
+    for (i; i < texs; i++) {
         draw_emit_vertex_attr(vinfo, EMIT_4F, INTERP_PERSPECTIVE,
-            draw_find_vs_output(r300->draw, TGSI_SEMANTIC_FOG, 0));
+            draw_find_vs_output(r300->draw, TGSI_SEMANTIC_GENERIC, i));
         vinfo->hwfmt[1] |= (R300_INPUT_CNTL_TC0 << i);
         vinfo->hwfmt[3] |= (4 << (3 * i));
     }
diff --git a/src/gallium/drivers/r300/r300_state_shader.c b/src/gallium/drivers/r300/r300_state_shader.c
index f27d723..d087771 100644
--- a/src/gallium/drivers/r300/r300_state_shader.c
+++ b/src/gallium/drivers/r300/r300_state_shader.c
@@ -31,6 +31,7 @@ static void r300_fs_declare(struct r300_fs_asm* assembler,
                 case TGSI_SEMANTIC_COLOR:
                     assembler->color_count++;
                     break;
+                case TGSI_SEMANTIC_FOG:
                 case TGSI_SEMANTIC_GENERIC:
                     assembler->tex_count++;
                     break;