It seems omniverse connector plugin doesn’t export normals, which causes tesselated objects to have artifacts.
The same issue is present on Maya-usd.
You can follow this thread to reproduce the problem : Reflections look broken on tessellated surfaces · Issue #962 · Autodesk/arnold-usd · GitHub
I just tested exporting the same object with omniverse connector and I got the same artifacts.
Omniverse does export normals, it’s just arnold renderer takes the normals from a different attribute name (as mentioned in that girhub issue) as opposed to the one Omniverse (and probably every other tools) writes normals to.
It sounds an Arnold render bug. We do export the normals.
How do you import the Usd exported by Arnold back to Maya? I tried to import it with MayaUsd. Arnold still fails to render it the same.
As you said, it’s really an arnold issue, I updated my original post. Both omniverse or maya-usd export normals fine, it’s just arnold doesn’t seem to take those into account, and when exporting with MtoA (from Arnold Menu > Scene export > Export Selection to USD), for me the render behaves same as with maya objects. I tested with both Maya-usd’s stage and with Arnold standin.
As I mentioned in the github post here : Reflections look broken on tessellated surfaces · Issue #962 · Autodesk/arnold-usd · GitHub
It seems Arnold uses a primvar as opposed to the normals attribute name for reading normals.