[Mesa-dev] [PATCH] draw/llvmpipe: fix transform feedback position + enable other extensions

Roland Scheidegger sroland at vmware.com
Thu Dec 13 07:29:00 PST 2012


Am 13.12.2012 11:26, schrieb Dave Airlie:
> From: Dave Airlie <airlied at redhat.com>
> 
> This builds on the previous draw/softpipe patch.
> 
> So llvmpipe does streamout calls after clip/viewport stages,
> but we have the pre-clip position stored for later use, so
> when we are doing transform feedback, and its the position vertex
> grab the vertex from the stored pre clip position.
> 
> The perfect fix is too probably add a codegen transform feedback
> stage in between shader and clip stages, but this is good enough
> for now.
> 
> Signed-off-by: Dave Airlie <airlied at redhat.com>
> ---
>  src/gallium/auxiliary/draw/draw_pt.h               |  2 +-
>  .../auxiliary/draw/draw_pt_fetch_shade_pipeline.c  |  2 +-
>  .../draw/draw_pt_fetch_shade_pipeline_llvm.c       |  2 +-
>  src/gallium/auxiliary/draw/draw_pt_so_emit.c       | 26 ++++++++++++++++++----
>  src/gallium/auxiliary/draw/draw_vs.c               |  1 +
>  src/gallium/drivers/llvmpipe/lp_screen.c           |  2 +-
>  6 files changed, 27 insertions(+), 8 deletions(-)
> 
> diff --git a/src/gallium/auxiliary/draw/draw_pt.h b/src/gallium/auxiliary/draw/draw_pt.h
> index 7d07363..764d311 100644
> --- a/src/gallium/auxiliary/draw/draw_pt.h
> +++ b/src/gallium/auxiliary/draw/draw_pt.h
> @@ -185,7 +185,7 @@ struct pt_emit *draw_pt_emit_create( struct draw_context *draw );
>   */
>  struct pt_so_emit;
>  
> -void draw_pt_so_emit_prepare( struct pt_so_emit *emit );
> +void draw_pt_so_emit_prepare(struct pt_so_emit *emit, boolean use_pre_clip_pos);
>  
>  void draw_pt_so_emit( struct pt_so_emit *emit,
>                        const struct draw_vertex_info *vert_info,
> diff --git a/src/gallium/auxiliary/draw/draw_pt_fetch_shade_pipeline.c b/src/gallium/auxiliary/draw/draw_pt_fetch_shade_pipeline.c
> index d1b76b1..2fc8220 100644
> --- a/src/gallium/auxiliary/draw/draw_pt_fetch_shade_pipeline.c
> +++ b/src/gallium/auxiliary/draw/draw_pt_fetch_shade_pipeline.c
> @@ -117,7 +117,7 @@ static void fetch_pipeline_prepare( struct draw_pt_middle_end *middle,
>  			    (boolean)draw->rasterizer->gl_rasterization_rules,
>  			    (draw->vs.edgeflag_output ? TRUE : FALSE) );
>  
> -   draw_pt_so_emit_prepare( fpme->so_emit );
> +   draw_pt_so_emit_prepare( fpme->so_emit, FALSE );
>  
>     if (!(opt & PT_PIPELINE)) {
>        draw_pt_emit_prepare( fpme->emit,
> diff --git a/src/gallium/auxiliary/draw/draw_pt_fetch_shade_pipeline_llvm.c b/src/gallium/auxiliary/draw/draw_pt_fetch_shade_pipeline_llvm.c
> index bfad54b..b0c18ed 100644
> --- a/src/gallium/auxiliary/draw/draw_pt_fetch_shade_pipeline_llvm.c
> +++ b/src/gallium/auxiliary/draw/draw_pt_fetch_shade_pipeline_llvm.c
> @@ -102,7 +102,7 @@ llvm_middle_end_prepare( struct draw_pt_middle_end *middle,
>  			    (boolean)draw->rasterizer->gl_rasterization_rules,
>  			    (draw->vs.edgeflag_output ? TRUE : FALSE) );
>  
> -   draw_pt_so_emit_prepare( fpme->so_emit );
> +   draw_pt_so_emit_prepare( fpme->so_emit, TRUE );
>  
>     if (!(opt & PT_PIPELINE)) {
>        draw_pt_emit_prepare( fpme->emit,
> diff --git a/src/gallium/auxiliary/draw/draw_pt_so_emit.c b/src/gallium/auxiliary/draw/draw_pt_so_emit.c
> index 80a164a..13d8470 100644
> --- a/src/gallium/auxiliary/draw/draw_pt_so_emit.c
> +++ b/src/gallium/auxiliary/draw/draw_pt_so_emit.c
> @@ -42,20 +42,24 @@ struct pt_so_emit {
>  
>     unsigned input_vertex_stride;
>     const float (*inputs)[4];
> -
> +   const float (*pre_clip_pos)[4];
>     boolean has_so;
> -
> +   boolean use_pre_clip_pos;
> +   int pos_idx;
>     unsigned emitted_primitives;
>     unsigned emitted_vertices;
>     unsigned generated_primitives;
>  };
>  
>  
> -void draw_pt_so_emit_prepare(struct pt_so_emit *emit)
> +void draw_pt_so_emit_prepare(struct pt_so_emit *emit, boolean use_pre_clip_pos)
>  {
>     struct draw_context *draw = emit->draw;
>  
> +   emit->use_pre_clip_pos = use_pre_clip_pos;
>     emit->has_so = (draw->vs.vertex_shader->state.stream_output.num_outputs > 0);
> +   if (use_pre_clip_pos)
> +      emit->pos_idx = draw_current_shader_position_output(draw);
>  
>     /* if we have a state with outputs make sure we have
>      * buffers to output to */
> @@ -87,12 +91,15 @@ static void so_emit_prim(struct pt_so_emit *so,
>     unsigned input_vertex_stride = so->input_vertex_stride;
>     struct draw_context *draw = so->draw;
>     const float (*input_ptr)[4];
> +   const float (*pcp_ptr)[4] = NULL;
>     const struct pipe_stream_output_info *state =
>        &draw->vs.vertex_shader->state.stream_output;
>     float *buffer;
>     int buffer_total_bytes[PIPE_MAX_SO_BUFFERS];
>  
>     input_ptr = so->inputs;
> +   if (so->use_pre_clip_pos)
> +      pcp_ptr = so->pre_clip_pos;
>  
>     ++so->generated_primitives;
>  
> @@ -117,12 +124,17 @@ static void so_emit_prim(struct pt_so_emit *so,
>  
>     for (i = 0; i < num_vertices; ++i) {
>        const float (*input)[4];
> +      const float (*pre_clip_pos)[4];
>        unsigned total_written_compos = 0;
>        int ob;
>        /*debug_printf("%d) vertex index = %d (prim idx = %d)\n", i, indices[i], prim_idx);*/
>        input = (const float (*)[4])(
>           (const char *)input_ptr + (indices[i] * input_vertex_stride));
>  
> +      if (pcp_ptr)
> +         pre_clip_pos = (const float (*)[4])(
> +         (const char *)pcp_ptr + (indices[i] * input_vertex_stride));
> +
>        for (slot = 0; slot < state->num_outputs; ++slot) {
>           unsigned idx = state->output[slot].register_index;
>           unsigned start_comp = state->output[slot].start_component;
> @@ -133,7 +145,10 @@ static void so_emit_prim(struct pt_so_emit *so,
>           buffer = (float *)((char *)draw->so.targets[ob]->mapping +
>                              draw->so.targets[ob]->target.buffer_offset +
>                              draw->so.targets[ob]->internal_offset) + state->output[slot].dst_offset;
> -         memcpy(buffer, &input[idx][start_comp], num_comps * sizeof(float));
> +         if (idx == so->pos_idx && pcp_ptr)
> +            memcpy(buffer, &pre_clip_pos[start_comp], num_comps * sizeof(float));
> +         else
> +            memcpy(buffer, &input[idx][start_comp], num_comps * sizeof(float));
>           total_written_compos += num_comps;
>        }
>        for (ob = 0; ob < draw->so.num_targets; ++ob)
> @@ -203,6 +218,9 @@ void draw_pt_so_emit( struct pt_so_emit *emit,
>     emit->emitted_primitives = 0;
>     emit->generated_primitives = 0;
>     emit->input_vertex_stride = input_verts->stride;
> +   if (emit->use_pre_clip_pos)
> +     emit->pre_clip_pos = (const float (*)[4])input_verts->verts->pre_clip_pos;
> +
>     emit->inputs = (const float (*)[4])input_verts->verts->data;
>  
>     /* XXX: need to flush to get prim_vbuf.c to release its allocation??*/
> diff --git a/src/gallium/auxiliary/draw/draw_vs.c b/src/gallium/auxiliary/draw/draw_vs.c
> index 785a903..266cca7 100644
> --- a/src/gallium/auxiliary/draw/draw_vs.c
> +++ b/src/gallium/auxiliary/draw/draw_vs.c
> @@ -80,6 +80,7 @@ draw_create_vertex_shader(struct draw_context *draw,
>     {
>        uint i;
>        bool found_clipvertex = FALSE;
> +      vs->position_output = -1;
>        for (i = 0; i < vs->info.num_outputs; i++) {
>           if (vs->info.output_semantic_name[i] == TGSI_SEMANTIC_POSITION &&
>               vs->info.output_semantic_index[i] == 0)
> diff --git a/src/gallium/drivers/llvmpipe/lp_screen.c b/src/gallium/drivers/llvmpipe/lp_screen.c
> index ab5a55b..25027e1 100644
> --- a/src/gallium/drivers/llvmpipe/lp_screen.c
> +++ b/src/gallium/drivers/llvmpipe/lp_screen.c
> @@ -188,7 +188,7 @@ llvmpipe_get_param(struct pipe_screen *screen, enum pipe_cap param)
>     case PIPE_CAP_MAX_STREAM_OUTPUT_INTERLEAVED_COMPONENTS:
>        return 16*4;
>     case PIPE_CAP_STREAM_OUTPUT_PAUSE_RESUME:
> -      return 0;
> +      return 1;
>     case PIPE_CAP_TGSI_CAN_COMPACT_VARYINGS:
>     case PIPE_CAP_TGSI_CAN_COMPACT_CONSTANTS:
>        return 0;
> 

This looks slightly confusing to me, as you've got a "use_pre_clip_pos"
boolean somehow indicating you'd use a post-clip position in the
non-llvm case (which of course isn't the case).
I'm not sure though how to make it less confusing easily (maybe split it
into a separate path for the llvm case?), but anyway this is just a
minor nitpick.

Reviewed-by: Roland Scheidegger <sroland at vmware.com>


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