diff options
Diffstat (limited to 'src/gallium/docs/source')
-rw-r--r-- | src/gallium/docs/source/tgsi.rst | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/src/gallium/docs/source/tgsi.rst b/src/gallium/docs/source/tgsi.rst index 6f850bf29fb..cbb8f74ab89 100644 --- a/src/gallium/docs/source/tgsi.rst +++ b/src/gallium/docs/source/tgsi.rst @@ -2512,8 +2512,10 @@ The Y component starts at zero and always increases but Y=0 may either indicate the top of the window or the bottom depending on the fragment coordinate origin convention (see TGSI_PROPERTY_FS_COORD_ORIGIN). The Z coordinate ranges from 0 to 1 to represent depth from the front -to the back of the Z buffer. The W component contains the reciprocol -of the interpolated vertex position W component. +to the back of the Z buffer. The W component contains the interpolated +reciprocal of the vertex position W component (corresponding to gl_Fragcoord, +but unlike d3d10 which interpolates the same 1/w but then gives back +the reciprocal of the interpolated value). Fragment shaders may also declare an output register with TGSI_SEMANTIC_POSITION. Only the Z component is writable. This allows |