Is the Normal Map used in S4S, a Height Map?

Both normal and height maps give models the appearance of more detail, but they’re different things. Height maps contain height information and normal maps contain angle information.

Height maps are greyscale, i.e. have one channel. White - up, black - down.

Normal maps are RGB, i.e. have three channels that store normal vectors.


TS4 normal maps have two channels. Only X and Y axes are stored in the map and the Z-axis is interpolated by the engine.

And textures are gray because RGB channels have the same information:


TS4 uses the OpenGL format (X+ Y+ Z+).


Sometimes we call a normal map a bump map, which is a bit of a misnomer. A bump map can be thought of as an old-school normal map. They are greyscale and contain much less information. But you can find different names (example).


The height map in SP is the same as everywhere else, so google for more info. If you use the default export (Document channels + Normal + AO), SP converts all height information into a normal map.