The original version was written by Stephen Thompson.
I replaced Eigen math by Bullet LinearMath, and added a dedicated 6x6 matrix solver.
Also I integrated support for collisions/contact constraints between btMultiBody and btRigidBody, and de-activation support.
See Demos/FeatherstoneMultiBodyDemo/Win32FeatherstoneMultiBodyDemo.cpp for example usage.
There is currently only support for contact constraints for btMultiBody.
Next on the list will be adding support for joint limit constraint for btMultiBody.
The implementation is still experimental/untested, the quality will improve in upcoming Bullet releases.
See http://www.youtube.com/watch?v=RV7sBAsKu4M and Bullet/Demos/RollingFrictionDemo
Fixes in FractureDemo (mouse picking constraint needs to be removed, otherwise constraint solver crashes/asserts)
Note that it can easily introduce instability at regular (60Hertz) simulation steps so it is generally best to not use the option.
If needed, use a very small internal step, such as 1000 Hertz (world->stepSimulation(dt,100,1./1000.f); or stepSimulation(1./1000.,0);
fix in infinite recursion in quickSort, exclude the pivot in each sub partition
disabled constraints don't merge simulation islands, and they don't disable collision between linked rigid bodies either.
It assumes a btCompoundShaps (where the childshapes are the pre-fractured pieces)
The btFractureBody is a class derived from btRigidBody, dealing with the collision impacts and connectivity/propagating the fracture.
Press the F key to toggle between fracture and glue mode
This is preliminary work, can be used as a starting point to implement your own fracture.
Thanks to Daniel KO Listas at the ODE mailing list
Don't build graphics demos when OpenGL or GLUT is not found
CMake will still build the non-graphical HelloWorld demo (output text to console)
Fix linker error: ThreadingDemo requires pthreads on UNIX systems
Thanks to reptor, see also http://bulletphysics.org/Bullet/phpBB3/posting.php?mode=reply&f=9&t=5748
Added assert to check for positive masses in btCompoundShape::calculatePrincipalAxisTransform, see Issue 399
Fixes for LLVM/GCC compilation issue in btSequentialImpulseConstraintSolver
(Untested) fix for Linux 64bit compilation Issue 409
Added Demos/ThreadingDemo showing how to use the cross-platform btThreadSupportInterface under Windows.
Added Demos/ParticlesOpenCL showing how to run the NVidia particle demo under OpenCL implementations by AMD, NVidia and MiniCL (CPU)
Please see HfFluidDemo.cpp for examples of how to use the height field fluid along with buoyant collision shapes.
The implementation is still lacking in my ways:
1) Need to complete more collision algorithms for buoyant collision shapes
2) Support compound buoyant shapes
3) The buoyancy model isn't that great
4) Fluid volume can be lost over time
Added very basic drawTriangle for btIDebugDraw, useful for basic softbody visualization.
Added btGjkEpa2, contribution by Nathanael Presson. Improved version of EPA penetration depth computation, more suitable for multi-core/SPU (less memory usage). Note: btGjkEpa2 is not enabled by default currently.
