Physical Material Masks?

Development Rendering
26

This is broken in 5.2, there is no way to add the Mask Texture, it’s permanently greyed out

27

Same, the mask texture parameter in the Physical Material Mask is permanently greyed out. I can’t plug anything into it. UE5.5

28

I have to wonder if that is linked to nanite enabled meshes - enable nanite, loose the ability to have physmat?

29

it doesn’t work on 5.6

30

It works. In 5.6 (and I guess on later versions too)

The things to know:

  • UV has to be correct and the channel selected correctly in the physical material mask asset

  • the mesh needs to have the flag Support Physical Material Mask :white_check_mark:

  • the texture can be a simple PNG texture with the correct colors values. (I disabled compress with alpha but I don’t know if it matters)

  • Right click on the Physical Material Mask asset to import it

  • The mesh needs to use complex collisions instead of the simple ones (probably? haven’t tested with simple collisions)

  • The tracing for the hit has to be set to complex (probably?)

  • Here’s the real tricky part: YOU CAN’T use a material instance. It simply doesn’t seem to work with a material instance. You need to set this up as a material on it’s own.

    https://youtu.be/AIVRdv5gNxE

31

To all who might require it, I have found this tutorial on the subject that explains it very clearly.

Hope this helps!