btQuantizedBvh has a version number, memory layout might be different now (due to aligned btVector3)
reorganized some data members of some classes, to reduce memory footprint
BulletMultiThreaded/NarrowPhaseCollision makes use of this boxBoxDistance.
Cache some values in src/BulletMultiThreaded/SpuContactManifoldCollisionAlgorithm.cpp, to avoid DMA transfers
2) Added btConvexSeparatingDistanceUtil: this allows caching of separating distance/vector as early-out to avoid convex-convex collision detection.
btConvexSeparatingDistanceUtil is used in src/BulletCollision/CollisionDispatch/btConvexConvexAlgorithm.cpp and can be controlled by btDispatcherInfo.m_useConvexConservativeDistanceUtil/m_convexConservativeDistanceThreshold
3) Use BulletMultiThreaded/vectormath/scalar/cpp/vectormath/scalar/cpp/vectormath_aos.h as fallback for non-PlayStation 3 Cell SPU/PPU platforms (used by boxBoxDistance).
Note there are other implementations in Extras/vectormath folder, that are potentially faster for IBM Cell SDK 3.0 SPU (libspe2)
+ fix related btMinkowskiSumShape issue in btSubsimplexConvexCast and btGjkConvexCast
+ add hitpoint for btSubsimplexConvexCast
+ reduce maximum number of iterations in conservative advancement/CCD implementations
- replaced all usage of heapSort by quickSort
- finished btMultiSapBroadphase. Still some work to be done to increase performance (faster add/remove from child broadphases.
uses currently AABB tree to locate child broadphase (should use grid), and sorted array takes too much time.
added hashtable based PairManager, thanks Pierre Terdiman and Erin Catto
improved friction in 'cachefriendly' solver
moved 'refreshcontactpoints' into collision detection, instead of solver
avoid linear search for contact manifolds, by storing an index
ignore margin for sphere shape (its entire radius is already margin)
avoid alignment checks in BVH serialization, they don't compile on 64-bit architectures
made 'bomb' box more heavy
Added btStackAlloc to Bullet (right now only used by btGjkEpa)
removed default constructors of btCollisionWorld/btDiscreteDynamicsWorld, to reduce link-time dependencies
improved performance of constraint solver by precalculating the cross product/impulse arm
added collision comparison code: ODE box-box, also sphere-triangle
added safety check into GJK, and an assert for AABB's that are very large
write partid/triangle index outside of GJK
CompoundShapes are tricky to manage with respect to persistent contact points and swapped order of btCollisionObjects,
During dispatch, finding an algorith etc. order can be swapped.
fixed several other issues, related to SimpleBroadphase (removing a proxy was not working)
