I'm building a 2D physics engine and I want to add broad-phase collision detection, though I only know of 2 or 3 types: Check everything against everything else (O(n^2) complexity) Sweep and Pru...

From the outset, collision detection feels like it is an O(n^2) problem. You have a bunch of objects and you need to check if each object is colliding with any of the other objects. However, I kn...