godot/thirdparty/bullet/BulletDynamics/ConstraintSolver/btHingeConstraint.h

/*
Bullet Continuous Collision Detection and Physics Library
Copyright (c) 2003-2006 Erwin Coumans  https://bulletphysics.org

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.
*/

/* Hinge Constraint by Dirk Gregorius. Limits added by Marcus Hennix at Starbreeze Studios */

#ifndef BT_HINGECONSTRAINT_H
#define BT_HINGECONSTRAINT_H

#define _BT_USE_CENTER_LIMIT_ 1

#include "LinearMath/btVector3.h"
#include "btJacobianEntry.h"
#include "btTypedConstraint.h"

class btRigidBody;

#ifdef BT_USE_DOUBLE_PRECISION
#define btHingeConstraintData btHingeConstraintDoubleData2  //rename to 2 for backwards compatibility, so we can still load the 'btHingeConstraintDoubleData' version
#define btHingeConstraintDataName "btHingeConstraintDoubleData2"
#else
#define btHingeConstraintData btHingeConstraintFloatData
#define btHingeConstraintDataName "btHingeConstraintFloatData"
#endif  //BT_USE_DOUBLE_PRECISION

enum btHingeFlags
{
	BT_HINGE_FLAGS_CFM_STOP = 1,
	BT_HINGE_FLAGS_ERP_STOP = 2,
	BT_HINGE_FLAGS_CFM_NORM = 4,
	BT_HINGE_FLAGS_ERP_NORM = 8
};

/// hinge constraint between two rigidbodies each with a pivotpoint that descibes the axis location in local space
/// axis defines the orientation of the hinge axis
ATTRIBUTE_ALIGNED16(class)
btHingeConstraint : public btTypedConstraint
{
#ifdef IN_PARALLELL_SOLVER
public:
#endif
	btJacobianEntry m_jac[3];     //3 orthogonal linear constraints
	btJacobianEntry m_jacAng[3];  //2 orthogonal angular constraints+ 1 for limit/motor

	btTransform m_rbAFrame;  // constraint axii. Assumes z is hinge axis.
	btTransform m_rbBFrame;

	btScalar m_motorTargetVelocity;
	btScalar m_maxMotorImpulse;

#ifdef _BT_USE_CENTER_LIMIT_
	btAngularLimit m_limit;
#else
	btScalar m_lowerLimit;
	btScalar m_upperLimit;
	btScalar m_limitSign;
	btScalar m_correction;

	btScalar m_limitSoftness;
	btScalar m_biasFactor;
	btScalar m_relaxationFactor;

	bool m_solveLimit;
#endif

	btScalar m_kHinge;

	btScalar m_accLimitImpulse;
	btScalar m_hingeAngle;
	btScalar m_referenceSign;

	bool m_angularOnly;
	bool m_enableAngularMotor;
	bool m_useSolveConstraintObsolete;
	bool m_useOffsetForConstraintFrame;
	bool m_useReferenceFrameA;

	btScalar m_accMotorImpulse;

	int m_flags;
	btScalar m_normalCFM;
	btScalar m_normalERP;
	btScalar m_stopCFM;
	btScalar m_stopERP;

public:
	BT_DECLARE_ALIGNED_ALLOCATOR();

	btHingeConstraint(btRigidBody & rbA, btRigidBody & rbB, const btVector3& pivotInA, const btVector3& pivotInB, const btVector3& axisInA, const btVector3& axisInB, bool useReferenceFrameA = false);

	btHingeConstraint(btRigidBody & rbA, const btVector3& pivotInA, const btVector3& axisInA, bool useReferenceFrameA = false);

	btHingeConstraint(btRigidBody & rbA, btRigidBody & rbB, const btTransform& rbAFrame, const btTransform& rbBFrame, bool useReferenceFrameA = false);

	btHingeConstraint(btRigidBody & rbA, const btTransform& rbAFrame, bool useReferenceFrameA = false);

	virtual void buildJacobian();

	virtual void getInfo1(btConstraintInfo1 * info);

	void getInfo1NonVirtual(btConstraintInfo1 * info);

	virtual void getInfo2(btConstraintInfo2 * info);

	void getInfo2NonVirtual(btConstraintInfo2 * info, const btTransform& transA, const btTransform& transB, const btVector3& angVelA, const btVector3& angVelB);

	void getInfo2Internal(btConstraintInfo2 * info, const btTransform& transA, const btTransform& transB, const btVector3& angVelA, const btVector3& angVelB);
	void getInfo2InternalUsingFrameOffset(btConstraintInfo2 * info, const btTransform& transA, const btTransform& transB, const btVector3& angVelA, const btVector3& angVelB);

	void updateRHS(btScalar timeStep);

	const btRigidBody& getRigidBodyA() const
	{
		return m_rbA;
	}
	const btRigidBody& getRigidBodyB() const
	{
		return m_rbB;
	}

	btRigidBody& getRigidBodyA()
	{
		return m_rbA;
	}

	btRigidBody& getRigidBodyB()
	{
		return m_rbB;
	}

	btTransform& getFrameOffsetA()
	{
		return m_rbAFrame;
	}

	btTransform& getFrameOffsetB()
	{
		return m_rbBFrame;
	}

	void setFrames(const btTransform& frameA, const btTransform& frameB);

	void setAngularOnly(bool angularOnly)
	{
		m_angularOnly = angularOnly;
	}

	void enableAngularMotor(bool enableMotor, btScalar targetVelocity, btScalar maxMotorImpulse)
	{
		m_enableAngularMotor = enableMotor;
		m_motorTargetVelocity = targetVelocity;
		m_maxMotorImpulse = maxMotorImpulse;
	}

	// extra motor API, including ability to set a target rotation (as opposed to angular velocity)
	// note: setMotorTarget sets angular velocity under the hood, so you must call it every tick to
	//       maintain a given angular target.
	void enableMotor(bool enableMotor) { m_enableAngularMotor = enableMotor; }
	void setMaxMotorImpulse(btScalar maxMotorImpulse) { m_maxMotorImpulse = maxMotorImpulse; }
	void setMotorTargetVelocity(btScalar motorTargetVelocity) { m_motorTargetVelocity = motorTargetVelocity; }
	void setMotorTarget(const btQuaternion& qAinB, btScalar dt);  // qAinB is rotation of body A wrt body B.
	void setMotorTarget(btScalar targetAngle, btScalar dt);

	void setLimit(btScalar low, btScalar high, btScalar _softness = 0.9f, btScalar _biasFactor = 0.3f, btScalar _relaxationFactor = 1.0f)
	{
#ifdef _BT_USE_CENTER_LIMIT_
		m_limit.set(low, high, _softness, _biasFactor, _relaxationFactor);
#else
		m_lowerLimit = btNormalizeAngle(low);
		m_upperLimit = btNormalizeAngle(high);
		m_limitSoftness = _softness;
		m_biasFactor = _biasFactor;
		m_relaxationFactor = _relaxationFactor;
#endif
	}

	btScalar getLimitSoftness() const
	{
#ifdef _BT_USE_CENTER_LIMIT_
		return m_limit.getSoftness();
#else
		return m_limitSoftness;
#endif
	}

	btScalar getLimitBiasFactor() const
	{
#ifdef _BT_USE_CENTER_LIMIT_
		return m_limit.getBiasFactor();
#else
		return m_biasFactor;
#endif
	}

	btScalar getLimitRelaxationFactor() const
	{
#ifdef _BT_USE_CENTER_LIMIT_
		return m_limit.getRelaxationFactor();
#else
		return m_relaxationFactor;
#endif
	}

	void setAxis(btVector3 & axisInA)
	{
		btVector3 rbAxisA1, rbAxisA2;
		btPlaneSpace1(axisInA, rbAxisA1, rbAxisA2);
		btVector3 pivotInA = m_rbAFrame.getOrigin();
		//		m_rbAFrame.getOrigin() = pivotInA;
		m_rbAFrame.getBasis().setValue(rbAxisA1.getX(), rbAxisA2.getX(), axisInA.getX(),
									   rbAxisA1.getY(), rbAxisA2.getY(), axisInA.getY(),
									   rbAxisA1.getZ(), rbAxisA2.getZ(), axisInA.getZ());

		btVector3 axisInB = m_rbA.getCenterOfMassTransform().getBasis() * axisInA;

		btQuaternion rotationArc = shortestArcQuat(axisInA, axisInB);
		btVector3 rbAxisB1 = quatRotate(rotationArc, rbAxisA1);
		btVector3 rbAxisB2 = axisInB.cross(rbAxisB1);

		m_rbBFrame.getOrigin() = m_rbB.getCenterOfMassTransform().inverse()(m_rbA.getCenterOfMassTransform()(pivotInA));

		m_rbBFrame.getBasis().setValue(rbAxisB1.getX(), rbAxisB2.getX(), axisInB.getX(),
									   rbAxisB1.getY(), rbAxisB2.getY(), axisInB.getY(),
									   rbAxisB1.getZ(), rbAxisB2.getZ(), axisInB.getZ());
		m_rbBFrame.getBasis() = m_rbB.getCenterOfMassTransform().getBasis().inverse() * m_rbBFrame.getBasis();
	}

	bool hasLimit() const
	{
#ifdef _BT_USE_CENTER_LIMIT_
		return m_limit.getHalfRange() > 0;
#else
		return m_lowerLimit <= m_upperLimit;
#endif
	}

	btScalar getLowerLimit() const
	{
#ifdef _BT_USE_CENTER_LIMIT_
		return m_limit.getLow();
#else
		return m_lowerLimit;
#endif
	}

	btScalar getUpperLimit() const
	{
#ifdef _BT_USE_CENTER_LIMIT_
		return m_limit.getHigh();
#else
		return m_upperLimit;
#endif
	}

	///The getHingeAngle gives the hinge angle in range [-PI,PI]
	btScalar getHingeAngle();

	btScalar getHingeAngle(const btTransform& transA, const btTransform& transB);

	void testLimit(const btTransform& transA, const btTransform& transB);

	const btTransform& getAFrame() const { return m_rbAFrame; };
	const btTransform& getBFrame() const { return m_rbBFrame; };

	btTransform& getAFrame() { return m_rbAFrame; };
	btTransform& getBFrame() { return m_rbBFrame; };

	inline int getSolveLimit()
	{
#ifdef _BT_USE_CENTER_LIMIT_
		return m_limit.isLimit();
#else
		return m_solveLimit;
#endif
	}

	inline btScalar getLimitSign()
	{
#ifdef _BT_USE_CENTER_LIMIT_
		return m_limit.getSign();
#else
		return m_limitSign;
#endif
	}

	inline bool getAngularOnly()
	{
		return m_angularOnly;
	}
	inline bool getEnableAngularMotor()
	{
		return m_enableAngularMotor;
	}
	inline btScalar getMotorTargetVelocity()
	{
		return m_motorTargetVelocity;
	}
	inline btScalar getMaxMotorImpulse()
	{
		return m_maxMotorImpulse;
	}
	// access for UseFrameOffset
	bool getUseFrameOffset() { return m_useOffsetForConstraintFrame; }
	void setUseFrameOffset(bool frameOffsetOnOff) { m_useOffsetForConstraintFrame = frameOffsetOnOff; }
	// access for UseReferenceFrameA
	bool getUseReferenceFrameA() const { return m_useReferenceFrameA; }
	void setUseReferenceFrameA(bool useReferenceFrameA) { m_useReferenceFrameA = useReferenceFrameA; }

	///override the default global value of a parameter (such as ERP or CFM), optionally provide the axis (0..5).
	///If no axis is provided, it uses the default axis for this constraint.
	virtual void setParam(int num, btScalar value, int axis = -1);
	///return the local value of parameter
	virtual btScalar getParam(int num, int axis = -1) const;

	virtual int getFlags() const
	{
		return m_flags;
	}

	virtual int calculateSerializeBufferSize() const;

	///fills the dataBuffer and returns the struct name (and 0 on failure)
	virtual const char* serialize(void* dataBuffer, btSerializer* serializer) const;
};

//only for backward compatibility
#ifdef BT_BACKWARDS_COMPATIBLE_SERIALIZATION
///this structure is not used, except for loading pre-2.82 .bullet files
struct btHingeConstraintDoubleData
{
	btTypedConstraintData m_typeConstraintData;
	btTransformDoubleData m_rbAFrame;  // constraint axii. Assumes z is hinge axis.
	btTransformDoubleData m_rbBFrame;
	int m_useReferenceFrameA;
	int m_angularOnly;
	int m_enableAngularMotor;
	float m_motorTargetVelocity;
	float m_maxMotorImpulse;

	float m_lowerLimit;
	float m_upperLimit;
	float m_limitSoftness;
	float m_biasFactor;
	float m_relaxationFactor;
};
#endif  //BT_BACKWARDS_COMPATIBLE_SERIALIZATION

///The getAccumulatedHingeAngle returns the accumulated hinge angle, taking rotation across the -PI/PI boundary into account
ATTRIBUTE_ALIGNED16(class)
btHingeAccumulatedAngleConstraint : public btHingeConstraint
{
protected:
	btScalar m_accumulatedAngle;

public:
	BT_DECLARE_ALIGNED_ALLOCATOR();

	btHingeAccumulatedAngleConstraint(btRigidBody & rbA, btRigidBody & rbB, const btVector3& pivotInA, const btVector3& pivotInB, const btVector3& axisInA, const btVector3& axisInB, bool useReferenceFrameA = false)
		: btHingeConstraint(rbA, rbB, pivotInA, pivotInB, axisInA, axisInB, useReferenceFrameA)
	{
		m_accumulatedAngle = getHingeAngle();
	}

	btHingeAccumulatedAngleConstraint(btRigidBody & rbA, const btVector3& pivotInA, const btVector3& axisInA, bool useReferenceFrameA = false)
		: btHingeConstraint(rbA, pivotInA, axisInA, useReferenceFrameA)
	{
		m_accumulatedAngle = getHingeAngle();
	}

	btHingeAccumulatedAngleConstraint(btRigidBody & rbA, btRigidBody & rbB, const btTransform& rbAFrame, const btTransform& rbBFrame, bool useReferenceFrameA = false)
		: btHingeConstraint(rbA, rbB, rbAFrame, rbBFrame, useReferenceFrameA)
	{
		m_accumulatedAngle = getHingeAngle();
	}

	btHingeAccumulatedAngleConstraint(btRigidBody & rbA, const btTransform& rbAFrame, bool useReferenceFrameA = false)
		: btHingeConstraint(rbA, rbAFrame, useReferenceFrameA)
	{
		m_accumulatedAngle = getHingeAngle();
	}
	btScalar getAccumulatedHingeAngle();
	void setAccumulatedHingeAngle(btScalar accAngle);
	virtual void getInfo1(btConstraintInfo1 * info);
};

struct btHingeConstraintFloatData
{
	btTypedConstraintData m_typeConstraintData;
	btTransformFloatData m_rbAFrame;  // constraint axii. Assumes z is hinge axis.
	btTransformFloatData m_rbBFrame;
	int m_useReferenceFrameA;
	int m_angularOnly;

	int m_enableAngularMotor;
	float m_motorTargetVelocity;
	float m_maxMotorImpulse;

	float m_lowerLimit;
	float m_upperLimit;
	float m_limitSoftness;
	float m_biasFactor;
	float m_relaxationFactor;
};

///do not change those serialization structures, it requires an updated sBulletDNAstr/sBulletDNAstr64
struct btHingeConstraintDoubleData2
{
	btTypedConstraintDoubleData m_typeConstraintData;
	btTransformDoubleData m_rbAFrame;  // constraint axii. Assumes z is hinge axis.
	btTransformDoubleData m_rbBFrame;
	int m_useReferenceFrameA;
	int m_angularOnly;
	int m_enableAngularMotor;
	double m_motorTargetVelocity;
	double m_maxMotorImpulse;

	double m_lowerLimit;
	double m_upperLimit;
	double m_limitSoftness;
	double m_biasFactor;
	double m_relaxationFactor;
	char m_padding1[4];
};

SIMD_FORCE_INLINE int btHingeConstraint::calculateSerializeBufferSize() const
{
	return sizeof(btHingeConstraintData);
}

///fills the dataBuffer and returns the struct name (and 0 on failure)
SIMD_FORCE_INLINE const char* btHingeConstraint::serialize(void* dataBuffer, btSerializer* serializer) const
{
	btHingeConstraintData* hingeData = (btHingeConstraintData*)dataBuffer;
	btTypedConstraint::serialize(&hingeData->m_typeConstraintData, serializer);

	m_rbAFrame.serialize(hingeData->m_rbAFrame);
	m_rbBFrame.serialize(hingeData->m_rbBFrame);

	hingeData->m_angularOnly = m_angularOnly;
	hingeData->m_enableAngularMotor = m_enableAngularMotor;
	hingeData->m_maxMotorImpulse = float(m_maxMotorImpulse);
	hingeData->m_motorTargetVelocity = float(m_motorTargetVelocity);
	hingeData->m_useReferenceFrameA = m_useReferenceFrameA;
#ifdef _BT_USE_CENTER_LIMIT_
	hingeData->m_lowerLimit = float(m_limit.getLow());
	hingeData->m_upperLimit = float(m_limit.getHigh());
	hingeData->m_limitSoftness = float(m_limit.getSoftness());
	hingeData->m_biasFactor = float(m_limit.getBiasFactor());
	hingeData->m_relaxationFactor = float(m_limit.getRelaxationFactor());
#else
	hingeData->m_lowerLimit = float(m_lowerLimit);
	hingeData->m_upperLimit = float(m_upperLimit);
	hingeData->m_limitSoftness = float(m_limitSoftness);
	hingeData->m_biasFactor = float(m_biasFactor);
	hingeData->m_relaxationFactor = float(m_relaxationFactor);
#endif

	// Fill padding with zeros to appease msan.
#ifdef BT_USE_DOUBLE_PRECISION
	hingeData->m_padding1[0] = 0;
	hingeData->m_padding1[1] = 0;
	hingeData->m_padding1[2] = 0;
	hingeData->m_padding1[3] = 0;
#endif

	return btHingeConstraintDataName;
}

#endif  //BT_HINGECONSTRAINT_H