[Piglit] [PATCH] arb_texture_query_lod: add tolerance for some comparisons

[Roland Scheidegger]

ping?

Am 09.09.2017 um 07:31 schrieb sroland at vmware.com:
> From: Roland Scheidegger <sroland at vmware.com>
> 
> Tolerance was added for the tests a while ago, but it looks like it was
> forgotten for the nearest_biased test (the nearest one has it).
> Also, for the linear test, add tolerance too when comparing x and y lodq
> results - the values should probably be the same mostly, however it's possible
> (due to interpolation inaccuracies) to get values just below 0 or above 3, in
> which case they will get clamped. (Could just do a clamp instead of allowing
> tolerance I suppose, but some tolerance might be allowed in any case there
> too.)
> 
> This is required for llvmpipe (with a in-progress change) to pass.
> ---
>  .../execution/fs-textureQueryLOD-linear.shader_test                 | 2 +-
>  .../execution/fs-textureQueryLOD-nearest-biased.shader_test         | 6 +++++-
>  2 files changed, 6 insertions(+), 2 deletions(-)
> 
> diff --git a/tests/spec/arb_texture_query_lod/execution/fs-textureQueryLOD-linear.shader_test b/tests/spec/arb_texture_query_lod/execution/fs-textureQueryLOD-linear.shader_test
> index 6afef71..bb2d8ba 100644
> --- a/tests/spec/arb_texture_query_lod/execution/fs-textureQueryLOD-linear.shader_test
> +++ b/tests/spec/arb_texture_query_lod/execution/fs-textureQueryLOD-linear.shader_test
> @@ -60,7 +60,7 @@ void main()
>      }
>  
>      vec2 queried_lod = textureQueryLOD(tex, gl_TexCoord[0].st);
> -    if (queried_lod.x != queried_lod.y) {
> +    if (!equal(queried_lod.x, queried_lod.y)) {
>  	discard;
>      }
>      if (!equal(queried_lod.x, lod)) {
> diff --git a/tests/spec/arb_texture_query_lod/execution/fs-textureQueryLOD-nearest-biased.shader_test b/tests/spec/arb_texture_query_lod/execution/fs-textureQueryLOD-nearest-biased.shader_test
> index 1e0c557..4487930 100644
> --- a/tests/spec/arb_texture_query_lod/execution/fs-textureQueryLOD-nearest-biased.shader_test
> +++ b/tests/spec/arb_texture_query_lod/execution/fs-textureQueryLOD-nearest-biased.shader_test
> @@ -51,6 +51,10 @@ GL_ARB_texture_query_lod
>  #define MAX_MIPMAP_LEVEL 3
>  uniform sampler2D tex;
>  uniform float lod;
> +
> +#define tolerance (1.0/255.0)
> +#define equal(x,y) (abs((x) - (y)) <= tolerance)
> +
>  void main()
>  {
>      /* The ARB_texture_query_lod spec says that if TEXTURE_MIN_FILTER is set
> @@ -69,7 +73,7 @@ void main()
>      }
>  
>      vec2 queried_lod = textureQueryLOD(tex, gl_TexCoord[0].st);
> -    if (queried_lod.x != min(queried_lod.y, MAX_MIPMAP_LEVEL)) {
> +    if (!equal(queried_lod.x, min(queried_lod.y, MAX_MIPMAP_LEVEL))) {
>  	discard;
>      }
>      if (queried_lod.x != min(nearest_lod + 1, MAX_MIPMAP_LEVEL)) {
>