Hey does anyone know of a good article on character control and collision response? I am having a problem that maybe someone can help with. I''m setting up the collision response system for a project where a character runs around and can jump (pretty standard motion). I''m trying to figure out how to determine the bounce velocity off of a wall or object. For example, I want the character (you can consider it a particle) to hit the surface and slide across. I know the math for reflecting a vector off of a surface, but what is the math for sliding across a surface and is there a way to blend between the two? thank you! ryan

when you want to slide, resolve the component of velocity parallel to the wall (the cross product of the wall''s normal N and the "up" vector)

eh if you are facing in direction D and trying to go forwards, and W=NxUp is paralell to the wall and floor,

slidevelocity=k*W

(D-kW).W=0 (the slide component meets the normal at 90'')

D.W
--- = k
W.W

********


A Problem Worthy of Attack
Proves It''s Worth by Fighting Back