i'm working on a project which involves some GPGPU work done in GLSL.
Some of the shaders need a lot of uniforms.
i.e. one is using 15 vec4 uniforms and 6 textures.
if i use all 15 vec4 uniforms on an ATI board (X1600 Pro AGP, X1900XT PCIe) the shader compile fine, but produce very low Framerates. Debugging lead me to the statement "unsupported language element, running shader in software" which seems to explain the slow framerates.
if i hardcode one of the variable and use only 14 uniforms everything works fine.
if i run the program on a nVidia Board (GF 6800 Ultra) everything works fine too (with all 15 uniforms)
did anyone before experience such problems? is this a known ATI driver Bug? GLSL specs require a minimum of 64 uniforms...
Thanx in advance