The Metal shader compiler fails to compile the atomic instructions
when operating on individual components of a vector. Spltting it
into four variables shouldn't make any difference for other
platforms, as they are accessed independently.
floatindex is clamped to the range [0, 9]. For non-negative numbers
floor() is equivalent to trunc(). Truncation happens implicitly when
converting to uint, so the floor() is unnecessary.
This was causing a warning in the shader compiler, as the rgb components
were not initialized. Which shouldn't be an issue, as the rgb is not
used in the blend equation, only the alpha. However, the lack of
initialization causes crashes in Intel's D3D shader compiler, so we'll
play nice and initialize all the channels.
Tested on a linux Intel Skylake integrated graphics with
blend_func_extended force-disabled, as it's the only platform I have
that doesn't crash with ubershaders and supports fb_fetch
It seems it doesn't like modifying inout variables in place - so instead
use a temporary for ocol0/ocol1 and only write them once at the end of
the shader
Cel-damage uses the color from the lighting stage of the vertex pipeline
as texture coordinates, but sets numColorChans to zero.
We now calculate the colors in all cases, but override the color before
writing it from the vertex shader if numColorChans is set to a lower value.
Currently, this is only the logic op bit, but this will be extended to
the framebuffer fetch/blend modes. In the future, when/if we move to
VideoCommon pipelines, this state will be part of the pipeline UID
anyway, and we can mask it out in the backend by using a two-level map,
so the shaders/programs are shared.
Stenzek
Tillmann Karras
Pierre BourdonandGitHub
spycrab
Lioncash
Jonathan Hamilton