Game Development Reference
In-Depth Information
More often than not, developers create their own much more simple physics systems
(which usually accounts for a high percentage of bugs in games if done wrong).
Unity recognized this limitation while building their 2D system and has pulled in another
world class physics system for 2D, called
Box2D
.
Tip
Games such as Angry Birds and Cut the Rope make heavy use of the 2D physics systems
to handle a lot of on-screen animation for free using physics.
Box2D has already been used and ported for many other platforms (including XNA), so it
makes complete sense for Unity; in most 2D games, you'll see a 4 times increase in the
physics performance. Care should be taken, as with every physics system; don't expect it
to solve all your problems. Code well and make sure that the standing objects generate in-
teractions.
Tip
If you want to see a great comparison between the 2D and 3D physics systems, refer to
this excellent post at
http://x-team.com/2013/11/Unity-v4-3-2d-vs-3d-physics/
.
Through Box2D, Unity adds several new physics collision options. They are as follows:
•
Rigidbody 2D
•
CircleCollider 2D
