ShaderMap 2 currently implements overlay and detail oriented methods (called pure rotation in SM2) for painting normals. I may do a write up of the SM2 blending modes and maths behind them in the future.
In the meantime here is a really great article I found on blending a detail normal map with a base normal map....
In the meantime here is a really great article I found on blending a detail normal map with a base normal map....
Create a custom theme


