Phya: Physical Audio for Virtual Worlds

Phya is a C++ library, that was created as an expandable system for adding physical audio to a virtual world. Phya released as Open Source under the ZLib license.
Also included is a new demo for the Bullet dynamics engine.

Visit or discuss here.

Bullet 2.69 Physics SDK released: split impulse, tear & pick Cloth and Soft Bodies

+ Added split impulse support, penetration recovery won’t add momentum
+ cloth/soft body improvements: picking (pick and drag), tearing (click and release without mouse move), preliminary support for btSoftBody versus compound and concave trimesh
+ Added new btDbvtBroadphase, based on dynamic AABB tree. It has the capability to do view frustum culling and front-to-back traversal. See Extras\CDTestFramework for view frustum culling sample.
+ Enabled new btGjkEpa2 penetration depth solver, thanks to Nathanael
+ Provide access to all persistent manifolds for a given btBroadphasePair, see CharacterDemo for sample usage
+ Added linear and angular motor for btSliderConstraint
+ Add penetration depth test for convexSweepTest
+ removed several warnings for Windows build, thanks to Martijn Reuvers
+ Added Mac Cocoa Xcode project, thanks to TomorrowPlus
+ use collision margin of btBvhTriangleMeshShape for convexTest, Thanks to reltham for the contribution.
+ added custom memory allocator registration, thanks to Sly.

Download Bullet 2.69 from the Bullet repository at Google Code.

Bullet 2.68 Physics SDK released: Soft Bodies and iPhone support

+ New BulletSoftBody library: cloth, rope and deformable volumes, including interaction with rigid bodies. Thanks Nathanael Presson.
+ Added btSliderConstraint
+ Added Extras/CdTestFrameWork, Thanks Pierre Terdiman
+ Added posix thread support (pthreads), Thanks Enrico.
+ Moved ConvexHull into Bullet/src
+ Moved optional quickstep and box-box collision detector to Bullet/src. Thanks Russell Smith for permission to re-distribute under the ZLib license.
+ Many bugfixes and improvements to BulletColladaConverter, btSubsimplexConvexCast, btMultiSapBroadphase, btOptimizedBvh

Download full SDK source code and precompiled Windows and Mac OSX Universal binary demos from

Wolfgang Engel developed the Oolong Engine 2 for iPhone, and initial Bullet support looks very promising. Unlike most other phones, the floating point performance of the iPhone is very good.

Thanks everyone for the hard work and feedback,


JBullet – Java port of Bullet Physics Library

Jezek announced a new release of JBullet, a Java port of Bullet. You can check the demos on-line:

Basic Demo: Launch Demo using Webstart
Generic Joint Demo: Launch Demo using Webstart
Bsp Demo: Launch Demo using Webstart
Static Concave Mesh Demo: Launch Demo using Webstart

Notes: requires Java 5.0, needs permissions for OpenGL rendering
For more information, visit the JBullet website at

Bullet 2.67 Physics SDK available now

Bullet 2.67 is available now from

  • Add support for fast batch raycasting on SPU / BulletMultiThreaded
  • Add support for 16 and 32-bit indexed triangle meshes in SPU / BulletMultiThreaded version.
  • Improved COLLADA Physics export snapshot from any Bullet btDynamicsWorld. Saving the physics world into .dae (xml textfile) can be useful for debugging etc.
  • Initial version for Character Control Demo
  • Bugfixes in ConvexCast support against the world.
  • Added btCapsuleShapeX/Z
  • Added btTypedUserInfo, useful for serialization
  • Added Stan Melax Convex Hull utility library in Extras/ConvexHull. This is useful to render non-polyhedral convex objects, and to simplify convex polyhedra.

The SVN repository is sychronized with the existing sourceforge repository.

Development is ongoing, and outstanding issues will roll into upcoming releases.

Feedback in this forum issue:

Parallel SPU Physics slides (GDC Physics Tutorial) available for download


The slides for the Game Developers Conference 2008 Tutorial, Physics for Game Developers, on parallel SPU physics are available for download now.

For feedback please use the

Physics Simulation Forum


Physics sessions at Game Developers Conference 2008


Following link provides some physics related sessions during upcoming GDC. There will be some demos of Bullet physics at the showfloor. It is a nice occasion to meet up, so if you are around, please get in touch!

More details here.

Collision Overload: reducing the impact in real-time physics

One of the distinguished projects at the Department of Computing at Imperial College London is about real-time physics simulation, using the Bullet physics library as case study.

At a first glance it looks like an interesting read!

iPhysics: Crayon Physics on the iPhone and

GPU Physics demos in the CUDA 1.1 SDK

The new CUDA 1.1 SDK includes some new physics demos including particle systems, FFT-based 2D fluids, and n-body gravitational simulation, all running on the GPU.

Thanks to Simesgreen for the link

Horde3D Physics Library Integration

Horde3D Bullet Physics integration

The project contains a small library that connects the Bullet Physics Engine to the Horde3D Graphics Engine.

The source code contains also a little example application and a patch for the Collada Converter of the Horde3D Engine version 0.11 that allows the usage of basic features of the Collada Physics extension.

This text is also available in german. A local cached copy of the source/demo is available too.

NVidia NVSG 4.0 VisSim demo uses Bullet physics library

NVSG VisSim demo using Bullet physics engineNVSG VisSim demo using Bullet physics engine

NVidia released a VisSim demo to showcase NVSG. They showed this demo in the NVidia booth at SIGGRAPH 2007 in San Diego.

Quote from the website: “The demo illustrates the integration of Physics (Bullet physics system), Audio (OpenAL), and Graphics through Producer, Cal3D, FreeType and of course NVSG. Bullet, OpenAL and Producer are all open source projects that are available from their respective repositories on the Internet. Nvidia and the NVSG team do not endorse any of these projects specifically, but they have worked very well for us and we would certainly recommend them. The source code to the VisSim demo is available below.”

Capcom drops Havok, develops their in-house physics engine

“Most interesting of the desired features, however, is the development of Capcom’s own physics system to replace the Havok middleware that it currently uses. ”

Explaining the decision, the page states that “Although middleware might increase efficiency, language discrepancies, response times for support/bugs and the loss of understanding on how our entire engine is structured leads us to feel that we get better results in a shorter period by developing our own engine.”

Intel buys Havok!

Dirk Gregorius posted on the physics forum that Intel is to acquire Havok, leading physics middleware company. This might change the physics simulation engine market considerably in the future.


Intel News Release
Heise News (German)
Game Star (German)
Forum discussion