The Farseer Physics Engine
The Farseer Physics Engine is an easy to use 2D physics engine designed specifically for Microsoft's XNA platform. The Farseer Physics Engine focuses on simplicity, useful features, and enabling the creation of fun, dynamic games.

The Features:

• Easy to use developer interface.
• Rigid-Body dynamics (forces, impulses, moment of inertia, etc…)
• Polygon - polygon collision detection. (convex and non-convex)
• 100% impulse based collision response.
• Joints (currently revolute joint, more to come)
• Springs and Angular Springs

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