The material is easy to implement and could just throw an error when used with materials supporting any type of transmission. It would be easy on CPU ... because any recursive material/texture is a killer for GPUs.B.Y.O.B. wrote: ↑Tue Jan 23, 2018 8:20 pm It would be much nicer to have a generic "double sided material" which accepts two materials as inputs for front and back, like the mix material.
But I don't know if that's possible to do in the material sampling code in case of translucent materials or glass.
I plan to add the support for OpenVDB because I used it in the past and it is absolutely amazing, Embree hair support is another good candidate. They are both going to be CPU-only features. The strategic decision here is if/how let the CPU and GPU render engines have different features.
The key point here is the user interface because having different feature sets for CPU and GPU can be very confusing for end users.