[Mesa-dev] [PATCH] [rfc] draw/vs: partly fix basevertex/vertex id

[Dave Airlie]

From: Dave Airlie <airlied at redhat.com>

This gets the basevertex from the draw depending on whether
it's an indexed or non-indexed draw.

We still fail a transform feedback test for vertex id, as
the vertex id actually an index id, and isn't getting translated
properly to a vertex id, suggestions on how/where to fix that welcome.
---
 src/gallium/auxiliary/draw/draw_vs_exec.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/src/gallium/auxiliary/draw/draw_vs_exec.c b/src/gallium/auxiliary/draw/draw_vs_exec.c
index 4f11ac7506c..dbd7aa551eb 100644
--- a/src/gallium/auxiliary/draw/draw_vs_exec.c
+++ b/src/gallium/auxiliary/draw/draw_vs_exec.c
@@ -128,18 +128,17 @@ vs_exec_run_linear(struct draw_vertex_shader *shader,
                          input[slot][3]);
          }
 #endif
+	 int basevertex = shader->draw->pt.user.eltSize ? shader->draw->pt.user.eltBias : shader->draw->start_index;
 
          if (shader->info.uses_vertexid) {
             unsigned vid = machine->SysSemanticToIndex[TGSI_SEMANTIC_VERTEXID];
             assert(vid < ARRAY_SIZE(machine->SystemValue));
-            machine->SystemValue[vid].xyzw[0].i[j] = i + j;
-            /* XXX this should include base vertex. Where to get it??? */
+            machine->SystemValue[vid].xyzw[0].i[j] = i + j + basevertex;
          }
          if (shader->info.uses_basevertex) {
             unsigned vid = machine->SysSemanticToIndex[TGSI_SEMANTIC_BASEVERTEX];
             assert(vid < ARRAY_SIZE(machine->SystemValue));
-            machine->SystemValue[vid].xyzw[0].i[j] = 0;
-            /* XXX Where to get it??? */
+            machine->SystemValue[vid].xyzw[0].i[j] = basevertex;
          }
          if (shader->info.uses_vertexid_nobase) {
             unsigned vid = machine->SysSemanticToIndex[TGSI_SEMANTIC_VERTEXID_NOBASE];
-- 
2.20.1