Game Physics Engine Development, 2nd Edition

18.2 Vector Mathematics 465

2. Collision detection is much simpler. 3D c ollision detection is an order of

magnitude more difficult (and therefore slower) than in 2D. An interesting con-

sequence of this is that 2D physics engines often implement more complex coll i-

sion detection schemes, including support for convex objects.

3. The simplicity allows you to experiment more with alternative algorithms, to add

new constraints, and to build more options for force and torque generators. This

in turn can provide a more interesting and varied physics experience for your

players.

4. Typically, 2D engines are more accurate at representing 2D physics. This is

because when we remove extra degrees of freedom from a 3D engine, we are

removing some of its accuracy ...