There are two material/texture systems in Xonotic that can work together.
This system is based off of the texture name, with the suffix denoting what the texture describes.
This is the texture as it will look to an observer without lighting or any other effects.
Xonotic uses OpenGL style tangent space normal map (Inverted Y/green channel). You can put height map in normal maps alpha channel and it will be used when offset or relief mapping is on. This will give your texture a 3d look.
If the TGA image is 32bits, the alpha channel will be loaded from the image.
note ONLY works with jpg at the moment (What does this mean? Why is there a tga entry for this then?)
Bump maps are like normal maps in that they allow a texture to be 3d. However, normal maps have higher priorities and so will overwrite bump maps. It is a better idea to use a normal map instead of a bump map, since the roughness of a bump map is limited by a cvar.
This map will make your texture more or less shiny. There may be colors in this map.
Areas textured with this map will always glow and shadows will not affect them.
Areas textured with this map will show the user’s custom or team color. Make it grayscale and leave same area 100% black in diffuse texture.
Like the above, but a secondary color. Does this still exist?
Second material system is simplified Quake 3 shader system.
The main difference is that you can use only 1 pass, with a few exceptions:
Lightmap pass is allowed
Blend shaders are allowed (blending two diffuse textures + lightmap). Same syntax as in quake3.