Player-driven procedural texturing

In the video game Spore we make heavy use of player-driven procedural texturing. Our aim is to amplify the user's creativity by allowing them to control a powerful procedural texturing system. We attempt to strike a balance between giving the player a full painting interface (desirable for highly skilled artists, but tedious for others), and limiting them to simple compositions of preauthored textures. We solve this problem differently for our two model kinds: creatures, and buildings/vehicles.