From 722ba1ad19d89277d01ff14f317eec3cf56ddd1e Mon Sep 17 00:00:00 2001 From: Brian Paul Date: Thu, 27 Jul 2017 11:52:33 -0600 Subject: [PATCH] gallium/docs: document automatic per-sample FS execution Both the GLSL 4.00 specs and DX10.1 specs specify that if a fragment shader uses the sample ID or sample position inputs, the shader is automatically run at per sample frequency. Document that expectation for gallium fragment shaders. Reviewed-by: Roland Scheidegger --- src/gallium/docs/source/tgsi.rst | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/src/gallium/docs/source/tgsi.rst b/src/gallium/docs/source/tgsi.rst index 0dd2ac0..d7817cc 100644 --- a/src/gallium/docs/source/tgsi.rst +++ b/src/gallium/docs/source/tgsi.rst @@ -3331,6 +3331,9 @@ contains the current sample id (i.e. gl_SampleID) as an unsigned int. Only the X component is used. If per-sample shading is not enabled, the result is (0, undef, undef, undef). +Note that if the fragment shader uses this system value, the fragment +shader is automatically executed at per sample frequency. + TGSI_SEMANTIC_SAMPLEPOS """"""""""""""""""""""" @@ -3340,6 +3343,9 @@ in the render target (i.e. gl_SamplePosition) when per-fragment shading is in effect. Position values are in the range [0, 1] where 0.5 is the center of the fragment. +Note that if the fragment shader uses this system value, the fragment +shader is automatically executed at per sample frequency. + TGSI_SEMANTIC_SAMPLEMASK """""""""""""""""""""""" -- 2.7.4