So I have been going through Tor Frick’s tutorial from Eat3D and trying to adapt his approach on modular textures from UDK to UE4.For vertex painting rust, he uses a normal map’s blue channel to store a mask then use it to create a blend mask in his material. When I try this however, it looks like ue4 is scrapping the blue channel and not displaying that mask as long as the compression is set as a normal map. If I change it to color it shows up.
The whole purpose is to have vertex painting conform to the pattern in the mask to give a more realistic look to the painted rust.
I am also looking for the same thing, except I want to use my blue channel for the Spec map. If anyone could give us a hint on how to achieve this, it would be very helpful
It’s been a while, but I’m wondering the same thing. I’ve looked at a couple of articles talking about derivative normal maps ( using only the RG channel from a texture to reconstruct a normal map ), but I can’t really seem to make it work using Default DXT1 compression settings. A lot of tutorials are talking about TC_Normalmap compression settings though, but UE4 right now only seems to have DXT5. I’ve also seen people talking about having 2 normal maps in 1 texture ( one using RG channels and the other using BA channels ), but it seems impossible with the DXT5 compression settings.
