2d Circle different ARC's Collision detection I've read about the way to detect collision between 2 circles or circle and line using trigonometry. But now I would like be able to detect which part of the circle arcs I'm hitting. For example I divided my circle to 4 different sized arcs. I would like to know which arc gets hit, 1, 2, 3, or 4? See image What is the best collision detection algorithm for this? Or what is this called?