From 394ea139c7cf577fe00d38634e697c3a740d4ccd Mon Sep 17 00:00:00 2001 From: Roland Scheidegger Date: Thu, 7 Aug 2014 20:34:17 +0200 Subject: draw: hack around weird primitive id input in gs The distinction between system values and ordinary inputs is not very obvious in gallium - further fueled by the fact that they use the same semantic names. Still, if there's any value which imho really is a system value, it's the primitive id input into the gs (while earlier (tessleation) stages could read it, it is _always_ generated by the system). For some odd reason though (which I'd classify as a bug but seems too complicated to fix) the glsl compiler in mesa treats this as an ordinary varying, and everything else after that (including the state tracker and other drivers) just go along with that. But input fetching in gs for llvm based draw was definitely limited to the ordinary (2-dimensional) inputs so only worked with other state trackers, the code was also additionally relying on tgsi_scan_shader filling uses_primid correctly which did not happen neither (would set it only for all stages if it was a system value, but only set it for the fragment shader if it was an input value). This fixes piglit glsl-1.50-geometry-primitive-id-restart and primitive-id-in in llvmpipe. Reviewed-by: Brian Paul --- src/gallium/auxiliary/draw/draw_gs.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'src/gallium/auxiliary/draw') diff --git a/src/gallium/auxiliary/draw/draw_gs.c b/src/gallium/auxiliary/draw/draw_gs.c index 2b6d2a02821..bbf515a9525 100644 --- a/src/gallium/auxiliary/draw/draw_gs.c +++ b/src/gallium/auxiliary/draw/draw_gs.c @@ -228,8 +228,7 @@ llvm_fetch_gs_input(struct draw_geometry_shader *shader, const float (*input_ptr)[4]; float (*input_data)[6][PIPE_MAX_SHADER_INPUTS][TGSI_NUM_CHANNELS][TGSI_NUM_CHANNELS] = &shader->gs_input->data; - shader->llvm_prim_ids[shader->fetched_prim_count] = - shader->in_prim_idx; + shader->llvm_prim_ids[shader->fetched_prim_count] = shader->in_prim_idx; input_ptr = shader->input; @@ -244,6 +243,11 @@ llvm_fetch_gs_input(struct draw_geometry_shader *shader, for (slot = 0, vs_slot = 0; slot < shader->info.num_inputs; ++slot) { if (shader->info.input_semantic_name[slot] == TGSI_SEMANTIC_PRIMID) { /* skip. we handle system values through gallivm */ + /* NOTE: If we hit this case here it's an ordinary input not a sv, + * even though it probably should be a sv. + * Not sure how to set it up as regular input however if that even, + * would make sense so hack around this later in gallivm. + */ } else { vs_slot = draw_gs_get_input_index( shader->info.input_semantic_name[slot], -- cgit v1.2.3