Vray RT GPU Error - 'warning: Texture * of type "BRDFBump" is not supported for bump'

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

warning: Texture * of type “BRDFBump” is not supported for bump

The * is a wildcard for simplicity but the actually error lists a bunch of materials with that message.

I’m using a regular bitmap in the bump slot with a grayscale jpg. The material is a VrayBlend that branches off into 3 VrayMtls (BRDF:Blinn), each with the same bump map. How can I get my bumps back?

EDIT: I replaced the bitmap node with a VRAYHDRI and the errors are gone but my bump maps still do not render. The bump mapping is seen in the light cache passes but disappears once the render begins.

2

Hello,

Could you share one such material - assigned to some simple geometry?

Best regards,
Yavor

3

You can look for the small rivets on the engine (which you should see in light cache). Ignore any parameter wiring errors, as those are there because I deleted a lot of objects to prepare the scene for testing.

EDIT: I’m noticing a lot of weird things using RT GPU right now. Render masks don’t work at all, DR keeps saying the slave node is timed out, GI still processes when unchecked, bump maps show in light cache but disappear when rendering starts. Do I have some odd setting clicked that’s causing all of this?

4

Thanks for the scene.
It is a national holiday here so our office is closed till Monday - I’ll check the scene then.

About the issues you are facing. The Render Mask is not supported in RT GPU. Turning GI off is also not supported - you can limit the GI depth from the RT settings and that will give you similar results.
You can see more details about RT GPU here: https://docs.chaosgroup.com/display/VRAY3MAX/V-Ray+RT+FAQ
and the list of supported features here: https://docs.chaosgroup.com/display/VRAY3MAX/V-Ray+RT+Supported+Features

The bump issues are happening because the Light Cache is calculated on the CPU and the rest of the rendering happens on the GPU. I have to check the scene and see why you are getting those messages - they show that there is some problem with the bump for the GPU.

5

Okay. I did a quick test by replacing the material with a new vraymtl with a simple noise map as a bump. Same result…shows in light cache but is not there when rendering on GPU. I tried both CUDA and opencl with the same result. I’m using a GTX 970

6

Are you using V-Ray 3.40? Older versions didn’t support noise in bump on the GPU.

7

Yes. I think I have it figured out. There’s a few factors that may have contributed. GPU resized my bump map which flattened it out and setting to VrayHDRI (to fix the error messages) may have altered the bump amount--making it way lower. It is working now though.

8

I checked the original scene - there is a bug that I’ve logged in our system. It is related to the “Output amount” multiplier (0.6) of the Bitmap texture used for bump. It has no effect for the bump but causes this bug. One possible workaround is to set the multiplier to 1.0 for the bump texture.

9

I totally missed the output multiplier. I did get it working in the end but thanks for the assistance.