texRBUFsize - returns the size of a given renderbuffer texture.
int2 texRBUFsize(samplerRBUF samp)
int2 texRBUFsize(isamplerRBUF samp)
int2 texRBUFsize(usamplerRBUF samp)
Sampler to be queried for size.
Given a sampler the size (width in x, height in y) of the corresponding
renderbuffer is returned as the result of the operation.
Renderbuffer samplers are created with the NV_eplicit_multisample
texRBUFsize is supported in gp4, gp5, and glsl profiles.