Okay I got some time to play with this and to me it would only make sense that you should be able to plug this black and white values into other items if your pulling the PBR stats of the item. Metallic , specular , roughness its just a # value 0-1 which you can pull from a color value right.
It does seem to work correctly for metallic and specular but not for roughness though. Maybe I am wrong about it working for specular but it seems to me that its working. I see a gleam or reflection where I expect it and none where I wouldn’t. IE metal shines and wood is dull.
Maybe I am thinking about this incorrectly though, but why wouldn’t roughness be able to take these same values through a texture black and white data. When I plug in a black and white to roughness it just seems to make everything dull.
If you cant mask it this way breaking apart the metallic vs wood through a black and white makes no sense if I still have to make everything rough or everything smooth. I feel like I am 90% of the way there and just missing something.
Edited to Add Dahmir you said “layered materials” can you provide a link? I know masking but layered is evading me. I also don’t see how masking is going to do this if I cant use a 0-1 color scale on roughness.