allow 'useMaximalCoordinates' and 'useFixedBase' in pybullet.loadURDF.
enable split impulse for btRigidBody, even in btMultiBodyDynamicsWorld.
allow initialization of velocity and apply force for btRigidBody in pybullet/shared memory API.
process contact parameters in URDF also for btRigidBody (friction, restitution etc)
add pybullet.setPhysicsEngineParameter with numSolverIterations, useSplitImpulse etc.
rolling friction -> only along the normal, until we have separate rolling friction coefficients on normal and non-normal directions
Don't teleport with grasping controller (VR)
Tune VR grasping a bit.
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;
Fix issue in contact/friction between btMultibody and btRigidBody (external force/torque of btRigidBody was not taken into account during contact/friction setup)
Allow 0.1 mm slop in contact, to avoid loosing contact. Todo: allow contacts with positive distance in multibody solver.
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)
Parse and use colors from URDF file (single rgba color per link, not per visual)
Rename btMultiBody 'stepVelocities' to 'computeAccelerationsArticulatedBodyAlgorithmMultiDof'
btHashMap, add const Value* operator[]
remove a few more obsolete btMultiBody methods (on the non-multi-dof path)
fix spelling typo in fillConstraintJacobianMultiDof (fil -> fill)
Add mention to Jakub Stepien for his work on btMultiBody
Allow picking of btMultiBody, using a btMultiBodyPoint2Point constraint, with limited strength to avoid adding too much energy to the system (= blowup)
Add btMultiBodyJointMotor, it can be used in combination with joint limit (just add the joint limit after the motor, to avoid jitter)
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.