I can't name it, but I know of one (and there are more) engine that lets you set a repetition size and it randomly generates patterns from a texture (i.e. with tiles, cement, etc.) *digs through his bookmarks* But it seems cool, is it worth the effort though? I don't think so
Paintball 2 needs better textures before it needs random patterns
edit: If this were done in real-time, and I can't imagine why it wouldn't be, then maps would take a lot of time to load for some players, and the option would probably be off by default. It is still reallllly neat.