Can't render more than 2 VrayBumpMtl materials chained together with GPU

[Alex_M]

I am unable to properly render more than 2 VrayBumpMtl materials chained together with the GPU engine. If more than 2 VrayBumpMtl materials are chained together, Vray GPU seems to render only the last one in the chain. The help docs don't seem to mention any such limitation. Is this a bug? CPU engine renders it fine. Please see the video attached.

[vladimir_krastev]

Hi Alex_M could you send us the scene? You can do that here or trough our contact form.

[Alex_M]

Sure, see attached.

[Muhammed_Hamed]

Hi Alex_M

Thanks for the report, I can see this is already logged in our system VGPU-4794
I did hit this in the past as well, I will increase the priority and talk to the developers

Best,
Muhammed

[Alex_M]

Thank you! Is there any other method of stacking multiple bump maps with GPU that I can use as a workaround in the meantime?

[^Lele^]

Blend the maps, and use one bumpMtl.
You may have to do some minor math as to how much a map ought to blend in, so to replicate the bump amount for each.

[Muhammed_Hamed]

Other than combining the maps in a composite node/layered texture, I don't think there is a way
We will fix this ASAP

Best,
Muhammed

[Muhammed_Hamed]

Lele beats me to it
Thanks Lele

[Alex_M]

I see. Thank you both!