Bullet 3D Game Multiphysics Library provides state of the art collision detection, soft body and rigid body dynamics.

• Used by many movie and game companies in AAA titles on Playstation 3, XBox 360, Nintendo Wii, PC and iPhone
• Modular extendible C++ design with hot-swap of most components
• Optimized back-ends for pthreads/Win32 Threads multi-threading and PS3 Cell SPU
• Preparation for OpenCL data parallel optimizations for upcoming Bullet 3.x

Bullet Collision Detection can be used on its own as a separate SDK without Bullet Dynamics

• Discrete and continuous collision detection (CCD)
• Swept collision queries
• Ray casting with custom collision filtering
• Generic convex support (using GJK), capsule, cylinder, cone, sphere, box and non-convex triangle meshes.
• Support for dynamic deformation of non-convex triangle meshes, by refitting the acceleration structures

Multi-physics support including:

• Rigid body dynamics including constraint solvers, generic constraints, ragdolls, hinge, ball-socket
• Support for constraint limits and motors
• Soft body support including cloth, rope and deformable
• Bullet is integrated into Cinema 4D, Lightwave, Blender and Carrara, and plugins for Maya, Houdini and 3ds Max are available
• Serialization of physics data in the cross-platform binary .bullet file format

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