I want to apply several materials to a landscape mesh. I understand that the normal way to do this is to manually select faces, which is what I've done in the 3D viewport with some place holder materials. However I also have material maps from World Machine. I want to use these material maps to select the faces of the mesh, where white is do select, black is don't select.
The reason I want to do it this way instead of just applying a bitmap texture to the entire landscape is because I want to use the materials that are already in the game engine I'll be importing the mesh into. So basically just make place holder material slots in blender and apply the actual materials after import to the game engine. I'm new to blender so I thought maybe this could be done by importing a black/white image in the uv editor and somehow selecting faces from that, but so far no luck.