Tip
Here is an important note: if you're going to just detect one of the following, you do not need to use a physics engine for your collision detection, but rather the listed method:
For rectangles intersecting rectangles, use
CGRectIntersectsRectFor points inside rectangles, use
CGRectContainsPointFor radius/distance intersection, use
ccpDistance
If you're going to be detecting collisions with non-rectangular and noncircular objects, feel free to read on.
Sometimes, all you're doing is sending objects across the screen, or rotating them with your custom actions, and you just want to know when two objects collide, but don't want the bouncing, pushing, and colliding that comes with the entire physics engine. Luckily, we can do that in Chipmunk.