Contacts Module
Manages the contacts between shapes.
This module provides the following classes:
- b2ChainAndCircleContact
- b2ChainAndPolygonContact
- b2CircleContact
- b2Contact
- b2ContactEdge
- b2ContactFactory
- b2ContactPositionConstraint
- b2ContactRegister
- b2ContactSolver
- b2ContactSolverDef
- b2ContactVelocityConstraint
- b2EdgeAndCircleContact
- b2EdgeAndPolygonContact
- b2PolygonAndCircleContact
- b2PolygonContact
- b2PositionSolverManifold
- b2VelocityConstraintPoint