Hi, picture two right angle triangles joined together along the Hypoteneuse. You see a rectangle or in my case a wall. I have put together a collision and response routine that works upto a point. My question is this. Why is it that when i am sliding along the wall, sometimes i pass through the wall at the point where the two polys join? Is it because the intersection point is not contained within either triangles, but lies on the very edge, making my routine fail? Or is it a flaw in my routine caused by something else? I''ve still to implement closest point on triangle to sphere. Maybe that will solve my problem but i won''t start that if there''s something not quite right with what i''v currently got. Any thoughts would be appreciated. cheers Mark.

ironfroggy, yes they do share the same points.

Mark