a04c29e8ab
The issue was happening when display device is set to None, which makes it so all the color transformation is a no-op which does not really require any LUT. This is something we can not know from Blender side easily, because LUT sampling and related logic is fully done in OCIO library itself. The following happens: - OCIO sees that no LUT is needed and uses simple pass-through logic in the color conversion function. - GLSL compiles sees that uniform used for LUT is unused in the GLSL code and strips it out. We can not know this from Blender side because technically any conversion to the same space might be a no-op and that we wouldn't know without some tricky parse of the OCIO configuration. So for now we simply avoid crash but are disabling checks for existence of the uniform. Ideally would be nice to have some GLSL-code parses which gets the uniforms from the code itself, so we can distinguish between typo in the uniform name and uniform being optimized out.