btRigidBody.h

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/*
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 RIGIDBODY_H
#define RIGIDBODY_H

#include "LinearMath/btAlignedObjectArray.h"
#include "LinearMath/btTransform.h"
#include "BulletCollision/BroadphaseCollision/btBroadphaseProxy.h"
#include "BulletCollision/CollisionDispatch/btCollisionObject.h"

class btCollisionShape;
class btMotionState;
class btTypedConstraint;


extern btScalar gDeactivationTime;
extern bool gDisableDeactivation;

#ifdef BT_USE_DOUBLE_PRECISION
#define btRigidBodyData btRigidBodyDoubleData
#define btRigidBodyDataName "btRigidBodyDoubleData"
#else
#define btRigidBodyData btRigidBodyFloatData
#define btRigidBodyDataName "btRigidBodyFloatData"
#endif //BT_USE_DOUBLE_PRECISION


enum    btRigidBodyFlags
{
    BT_DISABLE_WORLD_GRAVITY = 1
};


class btRigidBody  : public btCollisionObject
{

    btMatrix3x3 m_invInertiaTensorWorld;
    btVector3       m_linearVelocity;
    btVector3       m_angularVelocity;
    btScalar        m_inverseMass;
    btVector3       m_linearFactor;

    btVector3       m_gravity;  
    btVector3       m_gravity_acceleration;
    btVector3       m_invInertiaLocal;
    btVector3       m_totalForce;
    btVector3       m_totalTorque;
    
    btScalar        m_linearDamping;
    btScalar        m_angularDamping;

    bool            m_additionalDamping;
    btScalar        m_additionalDampingFactor;
    btScalar        m_additionalLinearDampingThresholdSqr;
    btScalar        m_additionalAngularDampingThresholdSqr;
    btScalar        m_additionalAngularDampingFactor;


    btScalar        m_linearSleepingThreshold;
    btScalar        m_angularSleepingThreshold;

    //m_optionalMotionState allows to automatic synchronize the world transform for active objects
    btMotionState*  m_optionalMotionState;

    //keep track of typed constraints referencing this rigid body
    btAlignedObjectArray<btTypedConstraint*> m_constraintRefs;

    int             m_rigidbodyFlags;
    
    int             m_debugBodyId;
    

protected:

    ATTRIBUTE_ALIGNED64(btVector3       m_deltaLinearVelocity);
    btVector3       m_deltaAngularVelocity;
    btVector3       m_angularFactor;
    btVector3       m_invMass;
    btVector3       m_pushVelocity;
    btVector3       m_turnVelocity;


public:


    struct  btRigidBodyConstructionInfo
    {
        btScalar            m_mass;

        btMotionState*      m_motionState;
        btTransform m_startWorldTransform;

        btCollisionShape*   m_collisionShape;
        btVector3           m_localInertia;
        btScalar            m_linearDamping;
        btScalar            m_angularDamping;

        btScalar            m_friction;
        btScalar            m_restitution;

        btScalar            m_linearSleepingThreshold;
        btScalar            m_angularSleepingThreshold;

        //Additional damping can help avoiding lowpass jitter motion, help stability for ragdolls etc.
        //Such damping is undesirable, so once the overall simulation quality of the rigid body dynamics system has improved, this should become obsolete
        bool                m_additionalDamping;
        btScalar            m_additionalDampingFactor;
        btScalar            m_additionalLinearDampingThresholdSqr;
        btScalar            m_additionalAngularDampingThresholdSqr;
        btScalar            m_additionalAngularDampingFactor;

        btRigidBodyConstructionInfo(    btScalar mass, btMotionState* motionState, btCollisionShape* collisionShape, const btVector3& localInertia=btVector3(0,0,0)):
        m_mass(mass),
            m_motionState(motionState),
            m_collisionShape(collisionShape),
            m_localInertia(localInertia),
            m_linearDamping(btScalar(0.)),
            m_angularDamping(btScalar(0.)),
            m_friction(btScalar(0.5)),
            m_restitution(btScalar(0.)),
            m_linearSleepingThreshold(btScalar(0.8)),
            m_angularSleepingThreshold(btScalar(1.f)),
            m_additionalDamping(false),
            m_additionalDampingFactor(btScalar(0.005)),
            m_additionalLinearDampingThresholdSqr(btScalar(0.01)),
            m_additionalAngularDampingThresholdSqr(btScalar(0.01)),
            m_additionalAngularDampingFactor(btScalar(0.01))
        {
            m_startWorldTransform.setIdentity();
        }
    };

    btRigidBody(    const btRigidBodyConstructionInfo& constructionInfo);

    btRigidBody(    btScalar mass, btMotionState* motionState, btCollisionShape* collisionShape, const btVector3& localInertia=btVector3(0,0,0));


    virtual ~btRigidBody()
        { 
                //No constraints should point to this rigidbody
        //Remove constraints from the dynamics world before you delete the related rigidbodies. 
                btAssert(m_constraintRefs.size()==0); 
        }

protected:

    void    setupRigidBody(const btRigidBodyConstructionInfo& constructionInfo);

public:

    void            proceedToTransform(const btTransform& newTrans); 
    
    static const btRigidBody*   upcast(const btCollisionObject* colObj)
    {
        if (colObj->getInternalType()&btCollisionObject::CO_RIGID_BODY)
            return (const btRigidBody*)colObj;
        return 0;
    }
    static btRigidBody* upcast(btCollisionObject* colObj)
    {
        if (colObj->getInternalType()&btCollisionObject::CO_RIGID_BODY)
            return (btRigidBody*)colObj;
        return 0;
    }
    
    void            predictIntegratedTransform(btScalar step, btTransform& predictedTransform) ;
    
    void            saveKinematicState(btScalar step);
    
    void            applyGravity();
    
    void            setGravity(const btVector3& acceleration);  

    const btVector3&    getGravity() const
    {
        return m_gravity_acceleration;
    }

    void            setDamping(btScalar lin_damping, btScalar ang_damping);

    btScalar getLinearDamping() const
    {
        return m_linearDamping;
    }

    btScalar getAngularDamping() const
    {
        return m_angularDamping;
    }

    btScalar getLinearSleepingThreshold() const
    {
        return m_linearSleepingThreshold;
    }

    btScalar getAngularSleepingThreshold() const
    {
        return m_angularSleepingThreshold;
    }

    void            applyDamping(btScalar timeStep);

    SIMD_FORCE_INLINE const btCollisionShape*   getCollisionShape() const {
        return m_collisionShape;
    }

    SIMD_FORCE_INLINE btCollisionShape* getCollisionShape() {
            return m_collisionShape;
    }
    
    void            setMassProps(btScalar mass, const btVector3& inertia);
    
    const btVector3& getLinearFactor() const
    {
        return m_linearFactor;
    }
    void setLinearFactor(const btVector3& linearFactor)
    {
        m_linearFactor = linearFactor;
        m_invMass = m_linearFactor*m_inverseMass;
    }
    btScalar        getInvMass() const { return m_inverseMass; }
    const btMatrix3x3& getInvInertiaTensorWorld() const { 
        return m_invInertiaTensorWorld; 
    }
        
    void            integrateVelocities(btScalar step);

    void            setCenterOfMassTransform(const btTransform& xform);

    void            applyCentralForce(const btVector3& force)
    {
        m_totalForce += force*m_linearFactor;
    }

    const btVector3& getTotalForce() const
    {
        return m_totalForce;
    };

    const btVector3& getTotalTorque() const
    {
        return m_totalTorque;
    };
    
    const btVector3& getInvInertiaDiagLocal() const
    {
        return m_invInertiaLocal;
    };

    void    setInvInertiaDiagLocal(const btVector3& diagInvInertia)
    {
        m_invInertiaLocal = diagInvInertia;
    }

    void    setSleepingThresholds(btScalar linear,btScalar angular)
    {
        m_linearSleepingThreshold = linear;
        m_angularSleepingThreshold = angular;
    }

    void    applyTorque(const btVector3& torque)
    {
        m_totalTorque += torque*m_angularFactor;
    }
    
    void    applyForce(const btVector3& force, const btVector3& rel_pos) 
    {
        applyCentralForce(force);
        applyTorque(rel_pos.cross(force*m_linearFactor));
    }
    
    void applyCentralImpulse(const btVector3& impulse)
    {
        m_linearVelocity += impulse *m_linearFactor * m_inverseMass;
    }
    
    void applyTorqueImpulse(const btVector3& torque)
    {
            m_angularVelocity += m_invInertiaTensorWorld * torque * m_angularFactor;
    }
    
    void applyImpulse(const btVector3& impulse, const btVector3& rel_pos) 
    {
        if (m_inverseMass != btScalar(0.))
        {
            applyCentralImpulse(impulse);
            if (m_angularFactor)
            {
                applyTorqueImpulse(rel_pos.cross(impulse*m_linearFactor));
            }
        }
    }

    void clearForces() 
    {
        m_totalForce.setValue(btScalar(0.0), btScalar(0.0), btScalar(0.0));
        m_totalTorque.setValue(btScalar(0.0), btScalar(0.0), btScalar(0.0));
    }
    
    void updateInertiaTensor();    
    
    const btVector3&     getCenterOfMassPosition() const { 
        return m_worldTransform.getOrigin(); 
    }
    btQuaternion getOrientation() const;
    
    const btTransform&  getCenterOfMassTransform() const { 
        return m_worldTransform; 
    }
    const btVector3&   getLinearVelocity() const { 
        return m_linearVelocity; 
    }
    const btVector3&    getAngularVelocity() const { 
        return m_angularVelocity; 
    }
    

    inline void setLinearVelocity(const btVector3& lin_vel)
    { 
        m_linearVelocity = lin_vel; 
    }

    inline void setAngularVelocity(const btVector3& ang_vel) 
    { 
        m_angularVelocity = ang_vel; 
    }

    btVector3 getVelocityInLocalPoint(const btVector3& rel_pos) const
    {
        //we also calculate lin/ang velocity for kinematic objects
        return m_linearVelocity + m_angularVelocity.cross(rel_pos);

        //for kinematic objects, we could also use use:
        //      return  (m_worldTransform(rel_pos) - m_interpolationWorldTransform(rel_pos)) / m_kinematicTimeStep;
    }

    void translate(const btVector3& v) 
    {
        m_worldTransform.getOrigin() += v; 
    }

    
    void    getAabb(btVector3& aabbMin,btVector3& aabbMax) const;




    
    SIMD_FORCE_INLINE btScalar computeImpulseDenominator(const btVector3& pos, const btVector3& normal) const
    {
        btVector3 r0 = pos - getCenterOfMassPosition();

        btVector3 c0 = (r0).cross(normal);

        btVector3 vec = (c0 * getInvInertiaTensorWorld()).cross(r0);

        return m_inverseMass + normal.dot(vec);

    }

    SIMD_FORCE_INLINE btScalar computeAngularImpulseDenominator(const btVector3& axis) const
    {
        btVector3 vec = axis * getInvInertiaTensorWorld();
        return axis.dot(vec);
    }

    SIMD_FORCE_INLINE void  updateDeactivation(btScalar timeStep)
    {
        if ( (getActivationState() == ISLAND_SLEEPING) || (getActivationState() == DISABLE_DEACTIVATION))
            return;

        if ((getLinearVelocity().length2() < m_linearSleepingThreshold*m_linearSleepingThreshold) &&
            (getAngularVelocity().length2() < m_angularSleepingThreshold*m_angularSleepingThreshold))
        {
            m_deactivationTime += timeStep;
        } else
        {
            m_deactivationTime=btScalar(0.);
            setActivationState(0);
        }

    }

    SIMD_FORCE_INLINE bool  wantsSleeping()
    {

        if (getActivationState() == DISABLE_DEACTIVATION)
            return false;

        //disable deactivation
        if (gDisableDeactivation || (gDeactivationTime == btScalar(0.)))
            return false;

        if ( (getActivationState() == ISLAND_SLEEPING) || (getActivationState() == WANTS_DEACTIVATION))
            return true;

        if (m_deactivationTime> gDeactivationTime)
        {
            return true;
        }
        return false;
    }


    
    const btBroadphaseProxy*    getBroadphaseProxy() const
    {
        return m_broadphaseHandle;
    }
    btBroadphaseProxy*  getBroadphaseProxy() 
    {
        return m_broadphaseHandle;
    }
    void    setNewBroadphaseProxy(btBroadphaseProxy* broadphaseProxy)
    {
        m_broadphaseHandle = broadphaseProxy;
    }

    //btMotionState allows to automatic synchronize the world transform for active objects
    btMotionState*  getMotionState()
    {
        return m_optionalMotionState;
    }
    const btMotionState*    getMotionState() const
    {
        return m_optionalMotionState;
    }
    void    setMotionState(btMotionState* motionState)
    {
        m_optionalMotionState = motionState;
        if (m_optionalMotionState)
            motionState->getWorldTransform(m_worldTransform);
    }

    //for experimental overriding of friction/contact solver func
    int m_contactSolverType;
    int m_frictionSolverType;

    void    setAngularFactor(const btVector3& angFac)
    {
        m_angularFactor = angFac;
    }

    void    setAngularFactor(btScalar angFac)
    {
        m_angularFactor.setValue(angFac,angFac,angFac);
    }
    const btVector3&    getAngularFactor() const
    {
        return m_angularFactor;
    }

    //is this rigidbody added to a btCollisionWorld/btDynamicsWorld/btBroadphase?
    bool    isInWorld() const
    {
        return (getBroadphaseProxy() != 0);
    }

    virtual bool checkCollideWithOverride(btCollisionObject* co);

    void addConstraintRef(btTypedConstraint* c);
    void removeConstraintRef(btTypedConstraint* c);

    btTypedConstraint* getConstraintRef(int index)
    {
        return m_constraintRefs[index];
    }

    int getNumConstraintRefs() const
    {
        return m_constraintRefs.size();
    }

    void    setFlags(int flags)
    {
        m_rigidbodyFlags = flags;
    }

    int getFlags() const
    {
        return m_rigidbodyFlags;
    }

    const btVector3& getDeltaLinearVelocity() const
    {
        return m_deltaLinearVelocity;
    }

    const btVector3& getDeltaAngularVelocity() const
    {
        return m_deltaAngularVelocity;
    }

    const btVector3& getPushVelocity() const 
    {
        return m_pushVelocity;
    }

    const btVector3& getTurnVelocity() const 
    {
        return m_turnVelocity;
    }


        
    btVector3& internalGetDeltaLinearVelocity()
    {
        return m_deltaLinearVelocity;
    }

    btVector3& internalGetDeltaAngularVelocity()
    {
        return m_deltaAngularVelocity;
    }

    const btVector3& internalGetAngularFactor() const
    {
        return m_angularFactor;
    }

    const btVector3& internalGetInvMass() const
    {
        return m_invMass;
    }
    
    btVector3& internalGetPushVelocity()
    {
        return m_pushVelocity;
    }

    btVector3& internalGetTurnVelocity()
    {
        return m_turnVelocity;
    }

    SIMD_FORCE_INLINE void  internalGetVelocityInLocalPointObsolete(const btVector3& rel_pos, btVector3& velocity ) const
    {
        velocity = getLinearVelocity()+m_deltaLinearVelocity + (getAngularVelocity()+m_deltaAngularVelocity).cross(rel_pos);
    }

    SIMD_FORCE_INLINE void  internalGetAngularVelocity(btVector3& angVel) const
    {
        angVel = getAngularVelocity()+m_deltaAngularVelocity;
    }


    //Optimization for the iterative solver: avoid calculating constant terms involving inertia, normal, relative position
    SIMD_FORCE_INLINE void internalApplyImpulse(const btVector3& linearComponent, const btVector3& angularComponent,const btScalar impulseMagnitude)
    {
        if (m_inverseMass)
        {
            m_deltaLinearVelocity += linearComponent*impulseMagnitude;
            m_deltaAngularVelocity += angularComponent*(impulseMagnitude*m_angularFactor);
        }
    }

    SIMD_FORCE_INLINE void internalApplyPushImpulse(const btVector3& linearComponent, const btVector3& angularComponent,btScalar impulseMagnitude)
    {
        if (m_inverseMass)
        {
            m_pushVelocity += linearComponent*impulseMagnitude;
            m_turnVelocity += angularComponent*(impulseMagnitude*m_angularFactor);
        }
    }
    
    void    internalWritebackVelocity()
    {
        if (m_inverseMass)
        {
            setLinearVelocity(getLinearVelocity()+ m_deltaLinearVelocity);
            setAngularVelocity(getAngularVelocity()+m_deltaAngularVelocity);
            //m_deltaLinearVelocity.setZero();
            //m_deltaAngularVelocity .setZero();
            //m_originalBody->setCompanionId(-1);
        }
    }


    void    internalWritebackVelocity(btScalar timeStep);

    


    virtual int calculateSerializeBufferSize()  const;

    virtual const char* serialize(void* dataBuffer,  class btSerializer* serializer) const;

    virtual void serializeSingleObject(class btSerializer* serializer) const;

};

//@todo add m_optionalMotionState and m_constraintRefs to btRigidBodyData
struct  btRigidBodyFloatData
{
    btCollisionObjectFloatData  m_collisionObjectData;
    btMatrix3x3FloatData        m_invInertiaTensorWorld;
    btVector3FloatData      m_linearVelocity;
    btVector3FloatData      m_angularVelocity;
    btVector3FloatData      m_angularFactor;
    btVector3FloatData      m_linearFactor;
    btVector3FloatData      m_gravity;  
    btVector3FloatData      m_gravity_acceleration;
    btVector3FloatData      m_invInertiaLocal;
    btVector3FloatData      m_totalForce;
    btVector3FloatData      m_totalTorque;
    float                   m_inverseMass;
    float                   m_linearDamping;
    float                   m_angularDamping;
    float                   m_additionalDampingFactor;
    float                   m_additionalLinearDampingThresholdSqr;
    float                   m_additionalAngularDampingThresholdSqr;
    float                   m_additionalAngularDampingFactor;
    float                   m_linearSleepingThreshold;
    float                   m_angularSleepingThreshold;
    int                     m_additionalDamping;
};

struct  btRigidBodyDoubleData
{
    btCollisionObjectDoubleData m_collisionObjectData;
    btMatrix3x3DoubleData       m_invInertiaTensorWorld;
    btVector3DoubleData     m_linearVelocity;
    btVector3DoubleData     m_angularVelocity;
    btVector3DoubleData     m_angularFactor;
    btVector3DoubleData     m_linearFactor;
    btVector3DoubleData     m_gravity;  
    btVector3DoubleData     m_gravity_acceleration;
    btVector3DoubleData     m_invInertiaLocal;
    btVector3DoubleData     m_totalForce;
    btVector3DoubleData     m_totalTorque;
    double                  m_inverseMass;
    double                  m_linearDamping;
    double                  m_angularDamping;
    double                  m_additionalDampingFactor;
    double                  m_additionalLinearDampingThresholdSqr;
    double                  m_additionalAngularDampingThresholdSqr;
    double                  m_additionalAngularDampingFactor;
    double                  m_linearSleepingThreshold;
    double                  m_angularSleepingThreshold;
    int                     m_additionalDamping;
    char    m_padding[4];
};



#endif