Does vrayDisplacement add a bump map effect?

V-Ray V-Ray for Maya General
1

Even if I set edge length to 10000 and max subdivs to 0, I get no geometry displacement on my mesh, but I still somehow get super fine bump-like detail. Does vrayDisplacement have some kind of bump effect that is independent of the subdivision of the mesh, like Arnolds autobump feature? How do I turn it off? I couldn’t find anything about this on the forums or in the documentation.

2

There shouldn’t be such an effect from the displacement. Could you post some screenshots? You could also try adding a Normals and BumpNormals render element and check it with displacement enabled and disabled - Normals will contain any changes to the actual geometry made by proper displacement, BumpNormals will contain any changes to the geometric normals from bump-mapping.

3

Yes, it does compute bump out of the displacement.

How do I turn it off? I couldn’t find anything about this on the forums or in the documentation.Enable the “Cache normals” option in the V-Ray displacement control attributes.

Best regards,
Vlado

4

Thanks Vlado! That’s a very cool feature, although even knowing what to look for, the (otherwise immaculate) documentation is very unclear about Cache normals and what it does in practice :). Debugging subdivisions and edge length is more difficult with it disabled.