i'm writing a first person perspective demo in directx 8, and i was wondering if anyone could give me any ideas on how they go about finding out which direction the user is facing...right now, if the user presses the up key, i increment both Z axis coordinates, etc, so the user "walks" forward. but if they turn and press up, there is an obvious problem...can anyone tell me the best way to know which way they are facing and also which axis' to increment/decrement based on this direction? thanks!