Register Combiner - Can I use Alpha for RGB?

OpenGL OpenGL: Advanced Coding
1

Hi,

I would like to smear the Primary Alpha component into General Combiner or Final Combiners RGB portion. Is it possible?

I want somehting like this
glCombinerInputNv(GL_COMBINER0_NV,GL_RGB,GL_VARIABLE_A_NV, GL_PRIMARY_COLOR_NV,GL_UNSIGNED_IDENTITY,GL_ALPHA)

In other words I would like to have the Primary Color’s Alpha component as one of the Inputs(smeared) for the RGB portion of the general combiner?

Could anybody let me know if this is possible?

Thanks,
Sundar

2

Yes. The spec says so.

3

Sure - smearing alpha into RGB this way will work fine in register combiners.

Cass