Ok, I've done it again. Found the answer with the help of a close colleague (not quite a roommate but still). XOR drawing in GL is done with 'logicop(LO_XOR)'. Doesn't work on all hardware, but does on mine, so I'm happy. --Guido van Rossum, CWI, Amsterdam <guido at cwi.nl> "It's probably pining for the fiords"