GPU - Unsupported features

V-Ray V-Ray GPU Issues
1

Hi,

Every once in a while I try GPU, and I wish I could use it more often because for interior renders it’s very nice on a 5090. But since I’m used to using CPU and used to the fact that about everything is supported, it’s difficult for me to know what is supported. I think I’ve asked this before, but a scene analyser would really be handy.

I know you have the supported features list but that’s really difficult to go through and a big time waste.

Take for instance this example. The material uses a vrayedges tex with variable width with a bercon noise. Plugged in a composite and in a vraybmpmtl, from a far this looks as if the wood is a bit chipped.

You will see that the bump of the woodgrain is almost gone, and the edgetex isn’t working.

This is the biggest reason I don’t use GPU. I checked all of the maps used with the list (took me 10 minutes), and everything should be supported. I probably missed something. Why is the bump a lot less strong? Where are the edges? Why isn’t the log warning me I’m using something that is not supported (I get other warnings but not about a map or something that isn’t supported.)

edit: Ok I just saw that the width multiplier is greyed out in GPU, although not stated on the compatibility list. But instead I tried to just use a regular noise map and a vraycomptex in multiply instead and it doesn’t work either. No effect.

CPU (correct):

CPU
CPU845×592 61 KB

GPU:

GPU
GPU845×592 55.5 KB

Shader:

image
image1012×494 35.5 KB

2

Indeed. I suggest you add a request for support for the Thickness tex slot here.

Otherwise, the supported features in the docs are generally the ones that aren’t greyed out in the host app.

Overall, it’s not really a good idea to switch to GPU mid-project, precisely because of the differences. It’s better to decide the render engine for a particular project beforehand.

3

Hi,

I wasn’t switching mid project, just started a new project and tried to use this shader setup.

But is there a reason why edgestex and a noisemap in multiply doesn’t work either? This is a quite basic setup.

Also (this applies to GPU and CPU), I tried plugging this edgestex in a displacement modifier to have the edges actually chipped but couldn’t get it to work.