Terrain looks bad

The two things that need doing here are
- Fix the materials to make them less glossy and use the correct colours
- Use the auto terrain generation to make the normal terrain. This can be done by auto generating it, saving it to a file, and then using the auto generated terrain as the basis to paint onto

No files, tests, or entry points are named. Start by locating the terrain material definitions and the auto terrain generation workflow; the work is done when materials use less glossy, correct colours and the generated terrain is saved and used as the basis for painting normal terrain.

Written by the indexing model from the issue text.