[Mesa-dev] RFC: ARB_sample_shading in gallium

[Ilia Mirkin]

Hey guys,

I was thinking of taking a shot at implementing ARB_sample_shading for
nv50 (well, nva3-nva8) this weekend. One of the issues is that it's
not implemented in gallium at all right now, so I need to pipe it
through somehow. I believe that the only piece of data that needs to
be piped through is the value returned by
_mesa_get_min_invocations_per_fragment, which is a function of the fp,
the drawbuffer, and the MS state. When that value is > 1, sample
shading is effectively enabled. (I guess even when it's == 1, things
like gl_SampleID still need to work, perhaps it's worth adding a
separate enabled bit too.)

Should this single integer get its own set_* callback, similar to
set_sample_mask, or should it be included somewhere, e.g.
pipe_framebuffer_state? Or even added to the set_sample_mask call?

Thanks,

  -ilia