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This notice may not be removed or altered from any source distribution. */ #ifndef BT_MULTIBODY_MLCP_CONSTRAINT_SOLVER_H #define BT_MULTIBODY_MLCP_CONSTRAINT_SOLVER_H #include "LinearMath/btMatrixX.h" #include "LinearMath/btThreads.h" #include "BulletDynamics/Featherstone/btMultiBodyConstraintSolver.h" class btMLCPSolverInterface; class btMultiBody; class btMultiBodyMLCPConstraintSolver : public btMultiBodyConstraintSolver { protected: /// \name MLCP Formulation for Rigid Bodies /// \{ /// A matrix in the MLCP formulation btMatrixXu m_A; /// b vector in the MLCP formulation. btVectorXu m_b; /// Constraint impulse, which is an output of MLCP solving. btVectorXu m_x; /// Lower bound of constraint impulse, \c m_x. btVectorXu m_lo; /// Upper bound of constraint impulse, \c m_x. btVectorXu m_hi; /// \} /// \name Cache Variables for Split Impulse for Rigid Bodies /// When using 'split impulse' we solve two separate (M)LCPs /// \{ /// Split impulse Cache vector corresponding to \c m_b. btVectorXu m_bSplit; /// Split impulse cache vector corresponding to \c m_x. btVectorXu m_xSplit; /// \} /// \name MLCP Formulation for Multibodies /// \{ /// A matrix in the MLCP formulation btMatrixXu m_multiBodyA; /// b vector in the MLCP formulation. btVectorXu m_multiBodyB; /// Constraint impulse, which is an output of MLCP solving. btVectorXu m_multiBodyX; /// Lower bound of constraint impulse, \c m_x. btVectorXu m_multiBodyLo; /// Upper bound of constraint impulse, \c m_x. btVectorXu m_multiBodyHi; /// \} /// Indices of normal contact constraint associated with frictional contact constraint for rigid bodies. /// /// This is used by the MLCP solver to update the upper bounds of frictional contact impulse given intermediate /// normal contact impulse. For example, i-th element represents the index of a normal constraint that is /// accosiated with i-th frictional contact constraint if i-th constraint is a frictional contact constraint. /// Otherwise, -1. btAlignedObjectArray<int> m_limitDependencies; /// Indices of normal contact constraint associated with frictional contact constraint for multibodies. /// /// This is used by the MLCP solver to update the upper bounds of frictional contact impulse given intermediate /// normal contact impulse. For example, i-th element represents the index of a normal constraint that is /// accosiated with i-th frictional contact constraint if i-th constraint is a frictional contact constraint. /// Otherwise, -1. btAlignedObjectArray<int> m_multiBodyLimitDependencies; /// Array of all the rigid body constraints btAlignedObjectArray<btSolverConstraint*> m_allConstraintPtrArray; /// Array of all the multibody constraints btAlignedObjectArray<btMultiBodySolverConstraint*> m_multiBodyAllConstraintPtrArray; /// MLCP solver btMLCPSolverInterface* m_solver; /// Count of fallbacks of using btSequentialImpulseConstraintSolver, which happens when the MLCP solver fails. int m_fallback; /// \name MLCP Scratch Variables /// The following scratch variables are not stateful -- contents are cleared prior to each use. /// They are only cached here to avoid extra memory allocations and deallocations and to ensure /// that multiple instances of the solver can be run in parallel. /// /// \{ /// Cache variable for constraint Jacobian matrix. btMatrixXu m_scratchJ3; /// Cache variable for constraint Jacobian times inverse mass matrix. btMatrixXu m_scratchJInvM3; /// Cache variable for offsets. btAlignedObjectArray<int> m_scratchOfs; /// \} /// Constructs MLCP terms, which are \c m_A, \c m_b, \c m_lo, and \c m_hi. virtual void createMLCPFast(const btContactSolverInfo& infoGlobal); /// Constructs MLCP terms for constraints of two rigid bodies void createMLCPFastRigidBody(const btContactSolverInfo& infoGlobal); /// Constructs MLCP terms for constraints of two multi-bodies or one rigid body and one multibody void createMLCPFastMultiBody(const btContactSolverInfo& infoGlobal); /// Solves MLCP and returns the success virtual bool solveMLCP(const btContactSolverInfo& infoGlobal); // Documentation inherited btScalar solveGroupCacheFriendlySetup( btCollisionObject** bodies, int numBodies, btPersistentManifold** manifoldPtr, int numManifolds, btTypedConstraint** constraints, int numConstraints, const btContactSolverInfo& infoGlobal, btIDebugDraw* debugDrawer) BT_OVERRIDE; // Documentation inherited btScalar solveGroupCacheFriendlyIterations( btCollisionObject** bodies, int numBodies, btPersistentManifold** manifoldPtr, int numManifolds, btTypedConstraint** constraints, int numConstraints, const btContactSolverInfo& infoGlobal, btIDebugDraw* debugDrawer) BT_OVERRIDE; public: BT_DECLARE_ALIGNED_ALLOCATOR() /// Constructor /// /// \param[in] solver MLCP solver. Assumed it's not null. /// \param[in] maxLCPSize Maximum size of LCP to solve using MLCP solver. If the MLCP size exceeds this number, sequaltial impulse method will be used. explicit btMultiBodyMLCPConstraintSolver(btMLCPSolverInterface* solver); /// Destructor virtual ~btMultiBodyMLCPConstraintSolver(); /// Sets MLCP solver. Assumed it's not null. void setMLCPSolver(btMLCPSolverInterface* solver); /// Returns the number of fallbacks of using btSequentialImpulseConstraintSolver, which happens when the MLCP /// solver fails. int getNumFallbacks() const; /// Sets the number of fallbacks. This function may be used to reset the number to zero. void setNumFallbacks(int num); /// Returns the constraint solver type. virtual btConstraintSolverType getSolverType() const; }; #endif // BT_MULTIBODY_MLCP_CONSTRAINT_SOLVER_H