I’ve made a quick demo of emboss bump mapping. There are some limitations, like if you move or rotate the plane the bump map won’t follow the light correctly.
- Colour: This could be done with an alpha texture, but the result would look faded. It would be better if Blender had a multiply blend mode.
- Complex meshes: Since meshes in the game engine only allow access to their vertices, not faces, there isn’t enough information to correctly bump map faces that aren’t centered at the origin.
Let me know what you think!