(for example solverInfo().m_leastSquaresResidualThreshold = 1e-7 and use large m_numSolverIterations
disable sphere-sphere contact cache, it is buggy (some contact point stay in the cache, when sphere penetrates more than total margins)
tweak some gpu demo settings
- fixing various race conditions throughout (usage of static vars, etc)
- addition of a few lightweight mutexes (which are compiled out by default)
- slight code rearrangement in discreteDynamicsWorld to facilitate multithreading
- PoolAllocator::allocate() can now be called when pool is full without
crashing (null pointer returned)
- PoolAllocator allocate and freeMemory, are OPTIONALLY threadsafe
(default is un-threadsafe)
- CollisionDispatcher no longer checks if the pool allocator is full
before calling allocate(), instead it just calls allocate() and
checks if the return is null -- this avoids a race condition
- SequentialImpulseConstraintSolver OPTIONALLY uses different logic in
getOrInitSolverBody() to avoid a race condition with kinematic bodies
- addition of 2 classes which together allow simulation islands to be run
in parallel:
- btSimulationIslandManagerMt
- btDiscreteDynamicsWorldMt
- MultiThreadedDemo example in the example browser demonstrating use of
OpenMP, Microsoft PPL, and Intel TBB
- use multithreading for other demos
- benchmark demo: add parallel raycasting
returns a pylist of contact points. Each point has the following data:
0 int m_contactFlags;//unused for now
1 int m_bodyUniqueIdA;
2 int m_bodyUniqueIdB;
3 int m_linkIndexA;
4 int m_linkIndexB;
5-6-7 double m_positionOnAInWS[3];//contact point location on object A, in world space coordinates
8-9-10 double m_positionOnBInWS[3];//contact point location on object A, in world space coordinates
11-12-13 double m_contactNormalOnBInWS[3];//the separating contact normal, pointing from object B towards object A
14 double m_contactDistance;//negative number is penetration, positive is distance.
15 double m_normalForce;
Added demos for rigid and multi body soft (compliant) contact.
Will also add simplified Hertz compliant contact, by dynamically modifying the ERP/CFM to mimic a non-linear spring.
Note that btManifoldPoint is growing too big, we need to implement proper contact constraints derived from btTypedConstraint.
CFM for contacts use world CFM value by default, and can override with custom CFM value using the
BT_CONTACT_FLAG_HAS_CONTACT_CFM stored in m_contactPointFlags.
Boolean m_lateralFrictionInitialized is replaced 'BT_CONTACT_FLAG_LATERAL_FRICTION_INITIALIZED' flag stored in int m_contactPointFlags in btManifoldPoint.
Enable successive over-relaxation parameter (SOR) for contacts. btMLCPSolver uses global CFM.
In one of the next commits, contact softness will be enabled btMultiBody contacts.
Also need to review use of CFM in btMLCPSolvers (only world CFM is used at the moment)
Will also add Erin Catto's local implicit version from the GDC 2015 tutorial
Added demo for btGeneric6DofSpring2Constraint, thanks to Gabor Puhr
Add gfxBridge.autogenerateGraphicsObjects method for Bullet 2 demos in new framework (need to implement all Bullet 2 collision shape types...)
Use 1,1,1 for local scaling in btStaticPlaneShape
contact force problems". The solver needs a lot of iterations, before the quality goes up (~ 1000)
Thanks to Gabor PUHR for the contribution!
Improved the btLemkeSolver.
Remove the sparse optimizations from the btMatrixX.h, replace it with explicit call to rowComputeNonZeroElements (only used in the btSolveProjectedGaussSeidel), it was likely slowing things down, without being useful.
Re-enable SIMD in the solver (was accidently disabled in Bullet 2.82 release)
with permission of the original author.
The Lemke implementation is not fully working yet:
1) we need to convert the lo-high LCP problem into a problem without the lo/high
2) we need to sort out the remaining instabilities, and report a failure if the max loopcount is reached etc.
We replaced the fmatvec library with our own LinearMath/btMatrixX.h, and STL std::vector with btAlignedObjectArray
Removed some warnings/potential issues: use fuzzyZero instead of isZero, and some warnings,
related to this issue 756
Added a PGS solver that uses the sparsity of the A matrix, just for testing (the equivalent sequential impulse solver is much faster, not having to allocate the big matrices)
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.
add compound shape support to BulletXmlWorldImporter and fix some compile issue under Debian (hopefully)
object picking change in the demos: create a ball-socket picking constraint when holding shift while mouse dragging, otherwise a fixed (6dof) constraint
add assert in constraint solver, when both objects have their inertia tensor rows set to zero
btPolyhedralContactClipping: add edge-edge contact point in findSeparatingAxis (similar to the default GJK case)
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);
(make sure to merge islands based on those predictive contacts too, added some check in the solver)
This fixes Issue 356.
Use same solver settings for AllBulletDemos
Make sure to embed the setCcdSweptSphereRadius inside the actual collision shape (for shoot box)
Applied picking cloth patch. Fixes Issue 646. Thanks to Dongsoo.
Applied patch Softbody updateConstraints. Fixes Issue 503. Thanks to Dave Bruce Phillips and Dongsoo.
Fix various warnigns under Mac OSX.
warmstarting for contact points was broken, fix in btPersistentManifold
enable split impulse by default (at the cost of some performance)
add the option for zero-length friction (instead of recomputing friction directions using btPlaneSpace), use the solver mode flag SOLVER_ALLOW_ZERO_LENGTH_FRICTION_DIRECTIONS
precompute lateral friction directions (in btManifoldResult)
remove the mConstraintRow[3] from btManifoldPoint, it just took a lot of memory with no benefits: fixed it in btParallelConstraintSolver
For OSX:
cd build
./premake_osx xcode4
for iOS:
cd build
./ios_build.sh
./ios_run.sh
Also integrated the branches/StackAllocation to make it easier to multi-thread collision detection in the near future. It avoids changing the btCollisionObject while performing collision detection.
As this is a large patch, some stuff might be temporarily broken, I'll keep an eye out on issues.
