I get strange issues with displacement using Vray GPU (CUDA or RTX, same kind of issue).
It’s a watch strap. I made it under 3dsmax, but people I’m working with are using C4D.
Using vray CPU, it’s pretty ok, but the scene is complex + animation, and so it goes much faster with vray GPU.
The material is pretty simple :
1) Vray mtl + normal map in bump
2) that Material goes inside a Vraybump mtl to add little details with a simple bump map
3) on the model itself, a displacement map (handmade 32 bits exr)
But, the watch strap doesn’t render correctly, except with CPU + normal displacement (see attached picture)
GPU Normal displacement : visible steps + it looses details of the bump map
2D displacement vray CPU : small issues but pretty much ok,
if then I swap to CUDA, the displacement texture goes totaly wrong
I tried to flip the textures, it does correct the position, mostly but not perfectly, but still looses bump details.
Here is a PSD with the original renders, you can even notice the object slightly moving to the right upper corner comparing vray CPU / GPU - 2D displacement
We need a simplified version of the wrest strap geometry and textures to reproduce the behavior on our side. I’m not able to reproduce in a simple scene
Please list your V-Ray version, Nvidia drivers and the GPU(s) you have
Upon testing I managed to reproduce this issue and I have reported it to our developers for fixing (bug ID: VC4D-1370). I will notify you once we have any updates on the matter. Thank you.
Also, as a workaround, you can add the material tag in the Material tag field for the UVW mapping, which seems to fix this issue. Please check this GIF. Thank you.
