This patch unifies the sRGB to Linear color space conversion between the
CPU and GPU compositors. This is because CPU uses an optimized path that
produces values that are very slightly off. To fix this, for the GPU, we
do the conversion CPU side instead of doing it in a shader. Since images
are cached, the performance implications are not significant.
Another added benefit is that we no longer get differences due to the
order of alpha pre-multiplication and sRGB conversion, demonstrated in
#114305. And we no longer require any preprocessing of the images.
This patch adds some new utilities to the Image Buffer module to assign
float, byte, and compressed buffers along with their color spaces. It
also adds an ownership flag to compressed data. Those were added as a
way to facilitate the implementation.
Pull Request: https://projects.blender.org/blender/blender/pulls/118624
4971b144a4