1.6. Collision Detection

Collision detection is the process of determining if two objects intersect. In two dimensions, this involves checking to see if one sprite shares the same pixels as another; in three dimensions, however, things are a bit more complex.

The easiest and most common method for 3D collision detection is done using spheres. Each 3D object is assigned a sphere that wraps the object. Collisions are tested for by calculating the distance between two spheres, and a collision is true if this distance is less than the sum of the radius of both spheres.