I was reading up on the two functions in the subject line and slapped together a little MFC test program that's on the site in my sig.
What exactly is gluUnProject "unprojecting"? I know my mouse arithmetic isn't perfect yet, but the numbers it's returning don't make any sense - they're not affected by whether or not the mouse is actually pointing at the cube.
So what exactly do these functions do and when might you want to use them? Pointers appreciated!
http://daltxcoltsfan.tripod.com/OpenGL/OpenGL.htm (please pardon the popups)