bullet/html/btContactSolverInfo_8h_source.html

/*

Bullet Continuous Collision Detection and Physics Library

Copyright (c) 2003-2006 Erwin Coumans  http://continuousphysics.com/Bullet/


This software is provided 'as-is', without any express or implied warranty.

In no event will the authors be held liable for any damages arising from the use of this software.

Permission is granted to anyone to use this software for any purpose,

including commercial applications, and to alter it and redistribute it freely,

subject to the following restrictions:


1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.

2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.

3. This notice may not be removed or altered from any source distribution.

*/


#ifndef BT_CONTACT_SOLVER_INFO

#define BT_CONTACT_SOLVER_INFO


#include "LinearMath/btScalar.h"


enum    btSolverMode

{

        SOLVER_RANDMIZE_ORDER = 1,

        SOLVER_FRICTION_SEPARATE = 2,

        SOLVER_USE_WARMSTARTING = 4,

        SOLVER_USE_2_FRICTION_DIRECTIONS = 16,

        SOLVER_ENABLE_FRICTION_DIRECTION_CACHING = 32,

        SOLVER_DISABLE_VELOCITY_DEPENDENT_FRICTION_DIRECTION = 64,

        SOLVER_CACHE_FRIENDLY = 128,

        SOLVER_SIMD = 256,

        SOLVER_INTERLEAVE_CONTACT_AND_FRICTION_CONSTRAINTS = 512,

        SOLVER_ALLOW_ZERO_LENGTH_FRICTION_DIRECTIONS = 1024

};


struct btContactSolverInfoData

{


        btScalar        m_tau;

        btScalar        m_damping;//global non-contact constraint damping, can be locally overridden by constraints during 'getInfo2'.

        btScalar        m_friction;

        btScalar        m_timeStep;

        btScalar        m_restitution;

        int             m_numIterations;

        btScalar        m_maxErrorReduction;

        btScalar        m_sor;//successive over-relaxation term

        btScalar        m_erp;//error reduction for non-contact constraints

        btScalar        m_erp2;//error reduction for contact constraints

        btScalar        m_globalCfm;//constraint force mixing for contacts and non-contacts

        btScalar        m_frictionERP;//error reduction for friction constraints

        btScalar        m_frictionCFM;//constraint force mixing for friction constraints


        int                     m_splitImpulse;

        btScalar        m_splitImpulsePenetrationThreshold;

        btScalar        m_splitImpulseTurnErp;

        btScalar        m_linearSlop;

        btScalar        m_warmstartingFactor;


        int                     m_solverMode;

        int     m_restingContactRestitutionThreshold;

        int                     m_minimumSolverBatchSize;

        btScalar        m_maxGyroscopicForce;

        btScalar        m_singleAxisRollingFrictionThreshold;

        btScalar        m_leastSquaresResidualThreshold;

        btScalar        m_restitutionVelocityThreshold;


};


struct btContactSolverInfo : public btContactSolverInfoData

{


        inline btContactSolverInfo()

        {

                m_tau = btScalar(0.6);

                m_damping = btScalar(1.0);

                m_friction = btScalar(0.3);

                m_timeStep = btScalar(1.f/60.f);

                m_restitution = btScalar(0.);

                m_maxErrorReduction = btScalar(20.);

                m_numIterations = 10;

                m_erp = btScalar(0.2);

                m_erp2 = btScalar(0.2);

                m_globalCfm = btScalar(0.);

                m_frictionERP = btScalar(0.2);//positional friction 'anchors' are disabled by default

                m_frictionCFM = btScalar(0.);

                m_sor = btScalar(1.);

                m_splitImpulse = true;

                m_splitImpulsePenetrationThreshold = -.04f;

                m_splitImpulseTurnErp = 0.1f;

                m_linearSlop = btScalar(0.0);

                m_warmstartingFactor=btScalar(0.85);

                //m_solverMode =  SOLVER_USE_WARMSTARTING |  SOLVER_SIMD | SOLVER_DISABLE_VELOCITY_DEPENDENT_FRICTION_DIRECTION|SOLVER_USE_2_FRICTION_DIRECTIONS|SOLVER_ENABLE_FRICTION_DIRECTION_CACHING;// | SOLVER_RANDMIZE_ORDER;

                m_solverMode = SOLVER_USE_WARMSTARTING | SOLVER_SIMD;// | SOLVER_RANDMIZE_ORDER;

                m_restingContactRestitutionThreshold = 2;//unused as of 2.81

                m_minimumSolverBatchSize = 128; //try to combine islands until the amount of constraints reaches this limit

                m_maxGyroscopicForce = 100.f;

                m_singleAxisRollingFrictionThreshold = 1e30f;

                m_leastSquaresResidualThreshold = 0.f;

                m_restitutionVelocityThreshold = 0.2f;//if the relative velocity is below this threshold, there is zero restitution

        }

};


struct btContactSolverInfoDoubleData

{

        double          m_tau;

        double          m_damping;//global non-contact constraint damping, can be locally overridden by constraints during 'getInfo2'.

        double          m_friction;

        double          m_timeStep;

        double          m_restitution;

        double          m_maxErrorReduction;

        double          m_sor;

        double          m_erp;//used as Baumgarte factor

        double          m_erp2;//used in Split Impulse

        double          m_globalCfm;//constraint force mixing

        double          m_splitImpulsePenetrationThreshold;

        double          m_splitImpulseTurnErp;

        double          m_linearSlop;

        double          m_warmstartingFactor;

        double          m_maxGyroscopicForce;

        double          m_singleAxisRollingFrictionThreshold;


        int                     m_numIterations;

        int                     m_solverMode;

        int                     m_restingContactRestitutionThreshold;

        int                     m_minimumSolverBatchSize;

        int                     m_splitImpulse;

        char            m_padding[4];


};

struct btContactSolverInfoFloatData

{

        float           m_tau;

        float           m_damping;//global non-contact constraint damping, can be locally overridden by constraints during 'getInfo2'.

        float           m_friction;

        float           m_timeStep;


        float           m_restitution;

        float           m_maxErrorReduction;

        float           m_sor;

        float           m_erp;//used as Baumgarte factor


        float           m_erp2;//used in Split Impulse

        float           m_globalCfm;//constraint force mixing

        float           m_splitImpulsePenetrationThreshold;

        float           m_splitImpulseTurnErp;


        float           m_linearSlop;

        float           m_warmstartingFactor;

        float           m_maxGyroscopicForce;

        float           m_singleAxisRollingFrictionThreshold;


        int                     m_numIterations;

        int                     m_solverMode;

        int                     m_restingContactRestitutionThreshold;

        int                     m_minimumSolverBatchSize;


        int                     m_splitImpulse;

        char            m_padding[4];

};


#endif //BT_CONTACT_SOLVER_INFO