Maps contain usually some mountains and are a projection from above. One way to distinguish the height level is by using colors as this is typically done by relief maps. The map that I’m creating uses color for different kinds of vegetation. Therefore there needs to be another approach. This image tutorial follows the same path as this video tutorial.
Colin Litster has a great example of how to create a copper plated roof in his book Blender 2.5 Materials and Textures Cookbook. The the image files of the are available from the publishers website, naturally they are copyright protected, which reduces their usefulness greatly. Furthermore the book gives good details on how to apply the images as textures in Blender, but the information on how to obtain/create the base image is sparse to non existent. Searching the web did not result in any image that would be usable. Therefore I set out to create the images from scratch.