This is so cool and I'm having quite a bit of fun messing around with it, but I really have no idea what I'm doing. First, I think N is "Normal to the surface" right? So what is P? Then you take P and put it into a Math Add, but what are we adding and why is it negative values and what do they represent? That goes into Clamp, what is a clamp? Does anybody know a good tutorial that explains how to "read" these things.