Sybaris
Thanks again!
I think, I'll stay with XPU for now.
Atm I'm having problems with normal maps under XPU. They always render the same, no matter what the normal effect setting is. Seems to be ignored...
If you're using XPU with the principled shader, all of the settings are ignored as the renderer does not support mantra shaders. The material library does a rough translation from principled shader to usd preview surface for use in the gl view and for basic support by other renderers. the translation is very limited though. I suggest no using the principled shader at all with karma. MaterialX is the official shading def of karma, so I would use that.