Roughness maps: eval_roughness()

[saeedhd96]

Hi,

I had a request to add a method eval_roughness(si) similar to eval_diffuse_reflectance(si) to the BSDF and BSDFPtr objects. like this in BRDF. I know it might be a lot of work to add all the methods to every BSDF, but I guess in most cases roughness and albedo are two things that people optimize for and thus need to render maps for. If I am not mistaken, currently we can't access roughness even through the AOV integrators.

[saeedhd96]

Would this be possible?

[wjakob]

I think we would be willing to entertain such a feature. However, no current projects depend on it, so it's difficult to justify spending time on this. Would you be willing to implement this feature and add a PR including tests for all BRDFs?

[saeedhd96]

Sure! I created it!