Box2DX is a C# port of Box2D - Erin Catto's 2D Physics Engine. You can find original C++ version on www.box2d.org

Collision:

• Continuous collision detection.
• Contact callbacks: add, persist, remove.
• Convex polyons and circles.
• Multiple shapes per body.
• One-shot contact manifolds.
• Incremental sweep-and-prune broadphase.
• Efficient pair management.
• Fast broadphase AABB queries.
• Collision groups and categories.

Physics:

• Continuous physics with time of impact island solver.
• Persistent body-joint-contact graph.
• Island solution and sleep management.
• Contact, friction, and restitution.
• Stable stacking with a linear-time solver.
• Revolute, prismatic, distance, pulley, gear, and mouse joints.
• Joint limits, motors, and friction.
• Momentum decoupled position correction.
• Fairly accurate reaction forces/impulses.

System:

• Centralized tuning parameters.
• Pure .NET 2.0 library.

Documentation: -

Testbed:

• OpenGL with Tao.Freeglut
• Graphical user interface
• Easily switch between tests using GUI
• Test framework for easily adding new tests
• Mouse picking and the bomb!
• VCS9 project files

The Library is free for commercial use and open source under the ZLib License.