Renderartifact on VRayBlendMtl

[MortenBøhne]

I'm trying to use VRayBlendMtl to mask out part of my geometry
but when the mesh is exactly on top of another mesh (with different shader), i get weird artifacts

How to recreate it:
make two identical cubes, assign a VRayBlendMtl to one of them, and render in vray


What i'm trying to do, is use it to mask out underlying geometry, in this example the body-mesh under the white sleeve

[Morbid Angel]

This won't work in any raytracer. You simply can't have two sets of geometries overlap each other, it doesn't play nice with raytracing. What you can do is transform one of the meshes on normal by a small value, then it should be fine.