Box2D Physics Engine

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

• Small block and stack allocators
• Centralized tuning parameters
• Highly portable C++ with no use of STL containers

Testbed

• OpenGL with Freeglut
• Graphical user interface with GLUI
• Easily switch between tests using GUI
• Test framework for easily adding new tests
• Mouse picking and the bomb!
• VC8 project files

Documentation

• User manual
• Doxygen document with real code comments.
• Active user forum