Solve issue with importance sampling at Principle shader clearcoat calculation
Open, ConfirmedPublic

Description

The clearcoat component of the Principled BSDF is currently using GTR1 for the D term while using GGX for importance sampling. This causes the clearcoat highlight to be non-consistent for increasing clearcoat roughness values.

With this patch, a switch from GTR1 to GGX is performed. This may produce some difference to the original Disney "principled" BRDF, but this should be negligibly small.

Details

Type
Patch