a unified interface to a number of different physics engines. Enables the use of multiple physics engines within one application. Not just a simple physics wrapper, it provides an extensible plug-in architecture as extended functionality for common simula
physics engine written primarily for games. As the name suggests, Box2D is a purely 2D engine. However, Box2D has grown beyond it's humble box simulating roots, and can now handle convex polygons and other shapes coming soon.