Decal with multi sub material assigned issue.

V-Ray V-Ray for 3ds Max Issues
1

So I came across this because of a user error, but thought i would send a scene in case its some issue I have unwittingly discovered.

I have attached a scene with a decal.

I mistakenly assigned a multi/sub material to it, as it was in a max group. With an empty multi/sub material theres not problem when i start an ipr render, however if i assign vray materials to it, then the render has a big delay trying to ‘compile geometry’.

I know you shouldnt add a multi/sub material to decals, but mistakes happen :slight_smile:

This is with latest release, max 2023 and GPU cuda render with recommended drivers.

Anyway I hope it might be useful info.
decal_multi_sub.zip (283 KB)

2

I managed to reproduce the issue on a simple scene and it turns out the slowdown appears when the base object is large enough. I presume there is some kind of an evaluation happening, which when a Multi/Sub-object mtl is present gets very slow. I’ll talk to the devs about this.

EDIT: Logged the issue (internal bug-tracker id: VGPU-6311).