Problem with the mapping when using TriplanarTex map

[Alex_M]

Hi,

Please check the screenshot below. Any ideas why this happens? If I use just a UVW map modifier in "Box" mode, the mapping works perfectly fine. There are no flipped normals and they all face in the same direction. This happens with both the CPU and the GPU engine. Let me know if you need the scene.

[Vizioen]

From the documentation (VRayTriplanarTex - V-Ray for 3ds Max - Global Site):

• If you wish to use a VRayNormalMap with VRayTriplanarTex in a material, assign the VRayNormalMap to the VRayTriplanarTex Texture map slot and then use the VRayTriplanarTex in your material. Linking in the other direction is not recommended.

[Alex_M]

Thanks, Vizioen . This works with CPU, but still not working with GPU. I am using the GPU engine for this project.

[hermit.crab]

Send or attach the scene so we can troubleshoot.

[Alex_M]

No worries. Simplified scene attached below.

[Vizioen]

There must be something weird with your geometry, if I apply it to a box it renders ok. Can't figure out what's wrong with your geo though.

[Joelaff]

Is the inconsistent polygon area? What if you quadrify mesh or retopologize?

[Alex_M]

Thanks for the suggestions, Vizioen and Joelaff . I think I solved the mystery! It turns out that if there are UVs that are very thin, the triplanar texture won't work properly with the GPU engine. Please check the video I recorded. If I apply box mapping to the object, the triplanar texture starts working properly. A bit counterproductive considering that the triplanar texture is normally used when you don't want to unwrap stuff. Again, seems to be a problem only with the GPU engine. I didn't have to do this when rendering with the CPU.

[hermit.crab]

This is an old one (internal bug-tracker ID: VGPU-5597). Basically, VRayNormalMaps with VRayTriplanar and GPU do not work well. I'll talk to the project manager, to see if we could bump its priority.

[Alex_M]

Good to know. In the meantime, I will use the workaround of applying box mapping when I see this problem again.