[Mesa-dev] [PATCH 7/9] gallium/u_tests: test a NULL texture sampler view

[Roland Scheidegger]

I don't think this is really correct. llvmpipe will return all zeros on
purpose, because this is d3d10 behavior (and dummy textures cannot work
correctly with d3d10). Traditionally both d3d9 and gl state trackers
used dummy textures, though I'm unsure what values they required (if
any). (For d3d9 though 0/0/0/1 would be somewhat odd since it would be
different to what bound textures but unused channels have to return, but
d3d9 is sometimes odd so it's possible. Well in that way d3d10 is odd
too...)
I certainly do agree though with the "don't crash" part.

Am 01.02.2015 um 18:15 schrieb Marek Olšák:
> From: Marek Olšák <marek.olsak at amd.com>
> 
> It shouldn't crash the GPU and it should return (0, 0, 0, 1).
> 
> This is r300 behavior, so I assume it's also DX9 behavior.
> Radeonsi can support this easily.
> ---
>  src/gallium/auxiliary/util/u_tests.c | 39 ++++++++++++++++++++++++++++++++++++
>  1 file changed, 39 insertions(+)
> 
> diff --git a/src/gallium/auxiliary/util/u_tests.c b/src/gallium/auxiliary/util/u_tests.c
> index 89ae840..9c8514c 100644
> --- a/src/gallium/auxiliary/util/u_tests.c
> +++ b/src/gallium/auxiliary/util/u_tests.c
> @@ -304,6 +304,44 @@ tgsi_vs_window_space_position(struct pipe_context *ctx)
>     util_report_result(pass);
>  }
>  
> +static void
> +null_sampler_view(struct pipe_context *ctx)
> +{
> +   struct cso_context *cso;
> +   struct pipe_resource *cb;
> +   void *fs, *vs;
> +   bool pass = true;
> +   static const float expected[] = {0, 0, 0, 1};
> +
> +   cso = cso_create_context(ctx);
> +   cb = util_create_texture2d(ctx->screen, 256, 256,
> +                              PIPE_FORMAT_R8G8B8A8_UNORM);
> +   util_set_common_states_and_clear(cso, ctx, cb);
> +
> +   ctx->set_sampler_views(ctx, PIPE_SHADER_FRAGMENT, 0, 1, NULL);
> +
> +   /* Fragment shader. */
> +   fs = util_make_fragment_tex_shader(ctx, TGSI_TEXTURE_2D,
> +                                      TGSI_INTERPOLATE_LINEAR);
> +   cso_set_fragment_shader_handle(cso, fs);
> +
> +   /* Vertex shader. */
> +   vs = util_set_passthrough_vertex_shader(cso, ctx, false);
> +   util_draw_fullscreen_quad(cso);
> +
> +   /* Probe pixels. */
> +   pass = pass && util_probe_rect_rgba(ctx, cb, 0, 0,
> +                                       cb->width0, cb->height0, expected);
> +
> +   /* Cleanup. */
> +   cso_destroy_context(cso);
> +   ctx->delete_vs_state(ctx, vs);
> +   ctx->delete_fs_state(ctx, fs);
> +   pipe_resource_reference(&cb, NULL);
> +
> +   util_report_result(pass);
> +}
> +
>  /**
>   * Run all tests. This should be run with a clean context after
>   * context_create.
> @@ -314,6 +352,7 @@ util_run_tests(struct pipe_screen *screen)
>     struct pipe_context *ctx = screen->context_create(screen, NULL);
>  
>     tgsi_vs_window_space_position(ctx);
> +   null_sampler_view(ctx);
>  
>     ctx->destroy(ctx);
>  
>