im working with clip planes and i have no info on what those 4 numbers are supposed to be in the plane equation. I think the first 3 numbers indicate a normal then the last one is how far up the normal the plane lies. i have this equation: planeEqn[] = {0, -1, 0, 0} and that makes a clipping plane that clips out everything above -1 (i think) my goal is to make it so that it clips everything BELOW -1 (basically just inverting the normal) i dont know anything about plane equations, haven''t learned that yet in school. Im just learning about dot products now on my own. If anybody has ANY info whatsoever please reply it would be a HUGE help. thanks alot.