HingeConstraint Class Reference

A hinge constraint constrains 2 bodies on a single point and allows only a single axis of rotation. More...

#include <HingeConstraint.h>

Inheritance diagram for HingeConstraint:

Public Member Functions
JPH_OVERRIDE_NEW_DELETE	HingeConstraint (Body &inBody1, Body &inBody2, const HingeConstraintSettings &inSettings)
	Construct hinge constraint. More...
virtual EConstraintSubType	GetSubType () const override
	Get the sub type of a constraint. More...
virtual void	NotifyShapeChanged (const BodyID &inBodyID, Vec3Arg inDeltaCOM) override
virtual void	SetupVelocityConstraint (float inDeltaTime) override
virtual void	ResetWarmStart () override
virtual void	WarmStartVelocityConstraint (float inWarmStartImpulseRatio) override
virtual bool	SolveVelocityConstraint (float inDeltaTime) override
virtual bool	SolvePositionConstraint (float inDeltaTime, float inBaumgarte) override
virtual void	DrawConstraint (DebugRenderer *inRenderer) const override
virtual void	DrawConstraintLimits (DebugRenderer *inRenderer) const override
virtual void	SaveState (StateRecorder &inStream) const override
	Saving state for replay. More...
virtual void	RestoreState (StateRecorder &inStream) override
	Restoring state for replay. More...
virtual Ref< ConstraintSettings >	GetConstraintSettings () const override
	Debug function to convert a constraint to its settings, note that this will not save to which bodies the constraint is connected to. More...
virtual Mat44	GetConstraintToBody1Matrix () const override
	Calculates the transform that transforms from constraint space to body 1 space. The first column of the matrix is the primary constraint axis (e.g. the hinge axis / slider direction), second column the secondary etc. More...
virtual Mat44	GetConstraintToBody2Matrix () const override
	Calculates the transform that transforms from constraint space to body 2 space. The first column of the matrix is the primary constraint axis (e.g. the hinge axis / slider direction), second column the secondary etc. More...
Vec3	GetLocalSpacePoint1 () const
	Get the attachment point for body 1 relative to body 1 COM (transform by Body::GetCenterOfMassTransform to take to world space) More...
Vec3	GetLocalSpacePoint2 () const
	Get the attachment point for body 2 relative to body 2 COM (transform by Body::GetCenterOfMassTransform to take to world space) More...
Vec3	GetLocalSpaceHingeAxis1 () const
Vec3	GetLocalSpaceHingeAxis2 () const
Vec3	GetLocalSpaceNormalAxis1 () const
Vec3	GetLocalSpaceNormalAxis2 () const
float	GetCurrentAngle () const
	Get the current rotation angle from the rest position. More...
void	SetMaxFrictionTorque (float inFrictionTorque)
float	GetMaxFrictionTorque () const
MotorSettings &	GetMotorSettings ()
const MotorSettings &	GetMotorSettings () const
void	SetMotorState (EMotorState inState)
EMotorState	GetMotorState () const
void	SetTargetAngularVelocity (float inAngularVelocity)
	rad/s More...
float	GetTargetAngularVelocity () const
void	SetTargetAngle (float inAngle)
	rad More...
float	GetTargetAngle () const
void	SetLimits (float inLimitsMin, float inLimitsMax)
	Update the rotation limits of the hinge, value in radians (see HingeConstraintSettings) More...
float	GetLimitsMin () const
float	GetLimitsMax () const
bool	HasLimits () const
const SpringSettings &	GetLimitsSpringSettings () const
	Update the limits spring settings. More...
SpringSettings &	GetLimitsSpringSettings ()
void	SetLimitsSpringSettings (const SpringSettings &inLimitsSpringSettings)
Public Member Functions inherited from TwoBodyConstraint
JPH_OVERRIDE_NEW_DELETE	TwoBodyConstraint (Body &inBody1, Body &inBody2, const TwoBodyConstraintSettings &inSettings)
	Constructor. More...
virtual EConstraintType	GetType () const override
	Get the type of a constraint. More...
virtual bool	IsActive () const override
	Solver interface. More...
virtual void	DrawConstraintReferenceFrame (DebugRenderer *inRenderer) const override
Body *	GetBody1 () const
	Access to the connected bodies. More...
Body *	GetBody2 () const
virtual Mat44	GetConstraintToBody1Matrix () const =0
	Calculates the transform that transforms from constraint space to body 1 space. The first column of the matrix is the primary constraint axis (e.g. the hinge axis / slider direction), second column the secondary etc. More...
virtual Mat44	GetConstraintToBody2Matrix () const =0
	Calculates the transform that transforms from constraint space to body 2 space. The first column of the matrix is the primary constraint axis (e.g. the hinge axis / slider direction), second column the secondary etc. More...
virtual void	BuildIslands (uint32 inConstraintIndex, IslandBuilder &ioBuilder, BodyManager &inBodyManager) override
	Link bodies that are connected by this constraint in the island builder. More...
virtual uint	BuildIslandSplits (LargeIslandSplitter &ioSplitter) const override
	Link bodies that are connected by this constraint in the same split. Returns the split index. More...
Public Member Functions inherited from Constraint
JPH_OVERRIDE_NEW_DELETE	Constraint (const ConstraintSettings &inSettings)
	Constructor. More...
virtual	~Constraint ()=default
	Virtual destructor. More...
virtual EConstraintType	GetType () const
	Get the type of a constraint. More...
virtual EConstraintSubType	GetSubType () const =0
	Get the sub type of a constraint. More...
uint32	GetConstraintPriority () const
void	SetConstraintPriority (uint32 inPriority)
void	SetNumVelocityStepsOverride (uint inN)
	Used only when the constraint is active. Override for the number of solver velocity iterations to run, 0 means use the default in PhysicsSettings::mNumVelocitySteps. The number of iterations to use is the max of all contacts and constraints in the island. More...
uint	GetNumVelocityStepsOverride () const
void	SetNumPositionStepsOverride (uint inN)
	Used only when the constraint is active. Override for the number of solver position iterations to run, 0 means use the default in PhysicsSettings::mNumPositionSteps. The number of iterations to use is the max of all contacts and constraints in the island. More...
uint	GetNumPositionStepsOverride () const
void	SetEnabled (bool inEnabled)
bool	GetEnabled () const
	Test if a constraint is enabled. More...
uint64	GetUserData () const
	Access to the user data, can be used for anything by the application. More...
void	SetUserData (uint64 inUserData)
virtual void	NotifyShapeChanged (const BodyID &inBodyID, Vec3Arg inDeltaCOM)=0
virtual void	ResetWarmStart ()=0
virtual void	BuildIslands (uint32 inConstraintIndex, IslandBuilder &ioBuilder, BodyManager &inBodyManager)=0
	Link bodies that are connected by this constraint in the island builder. More...
virtual uint	BuildIslandSplits (LargeIslandSplitter &ioSplitter) const =0
	Link bodies that are connected by this constraint in the same split. Returns the split index. More...
virtual void	DrawConstraint (DebugRenderer *inRenderer) const =0
virtual void	DrawConstraintLimits (DebugRenderer *inRenderer) const
virtual void	DrawConstraintReferenceFrame (DebugRenderer *inRenderer) const
float	GetDrawConstraintSize () const
	Size of constraint when drawing it through the debug renderer. More...
void	SetDrawConstraintSize (float inSize)
virtual void	SaveState (StateRecorder &inStream) const
	Saving state for replay. More...
virtual void	RestoreState (StateRecorder &inStream)
	Restoring state for replay. More...
virtual Ref< ConstraintSettings >	GetConstraintSettings () const =0
	Debug function to convert a constraint to its settings, note that this will not save to which bodies the constraint is connected to. More...
Public Member Functions inherited from RefTarget< Constraint >
	RefTarget ()=default
	Constructor. More...
	RefTarget (const RefTarget &)
	~RefTarget ()
	assert no one is referencing us More...
void	SetEmbedded () const
RefTarget &	operator= (const RefTarget &)
	Assignment operator. More...
uint32	GetRefCount () const
	Get current refcount of this object. More...
void	AddRef () const
	Add or release a reference to this object. More...
void	Release () const
Public Member Functions inherited from NonCopyable
	NonCopyable ()=default
	NonCopyable (const NonCopyable &)=delete
void	operator= (const NonCopyable &)=delete

Get Lagrange multiplier from last physics update (the linear/angular impulse applied to satisfy the constraint)
Vec3	GetTotalLambdaPosition () const
Vector< 2 >	GetTotalLambdaRotation () const
float	GetTotalLambdaRotationLimits () const
float	GetTotalLambdaMotor () const

Additional Inherited Members
Static Public Member Functions inherited from RefTarget< Constraint >
static int	sInternalGetRefCountOffset ()
	INTERNAL HELPER FUNCTION USED BY SERIALIZATION. More...
Protected Member Functions inherited from Constraint
void	ToConstraintSettings (ConstraintSettings &outSettings) const
	Helper function to copy settings back to constraint settings for this base class. More...
Protected Attributes inherited from TwoBodyConstraint
Body *	mBody1
	The two bodies involved. More...
Body *	mBody2
Protected Attributes inherited from Constraint
float	mDrawConstraintSize
	Size of constraint when drawing it through the debug renderer. More...
Protected Attributes inherited from RefTarget< Constraint >
atomic< uint32 >	mRefCount
	Current reference count. More...
Static Protected Attributes inherited from RefTarget< Constraint >
static constexpr uint32	cEmbedded
	A large value that gets added to the refcount to mark the object as embedded. More...

Detailed Description

A hinge constraint constrains 2 bodies on a single point and allows only a single axis of rotation.

Constructor & Destructor Documentation

HingeConstraint()

HingeConstraint::HingeConstraint	(	Body &	inBody1,
		Body &	inBody2,
		const HingeConstraintSettings &	inSettings
	)

Construct hinge constraint.

Member Function Documentation

DrawConstraint()

void HingeConstraint::DrawConstraint ( DebugRenderer *  inRenderer ) const

overridevirtual

Implements Constraint.

DrawConstraintLimits()

void HingeConstraint::DrawConstraintLimits ( DebugRenderer *  inRenderer ) const

overridevirtual

Reimplemented from Constraint.

GetConstraintSettings()

Ref< ConstraintSettings > HingeConstraint::GetConstraintSettings ( ) const

overridevirtual

Debug function to convert a constraint to its settings, note that this will not save to which bodies the constraint is connected to.

Implements Constraint.

GetConstraintToBody1Matrix()

Mat44 HingeConstraint::GetConstraintToBody1Matrix ( ) const

overridevirtual

Calculates the transform that transforms from constraint space to body 1 space. The first column of the matrix is the primary constraint axis (e.g. the hinge axis / slider direction), second column the secondary etc.

Implements TwoBodyConstraint.

GetConstraintToBody2Matrix()

Mat44 HingeConstraint::GetConstraintToBody2Matrix ( ) const

overridevirtual

Calculates the transform that transforms from constraint space to body 2 space. The first column of the matrix is the primary constraint axis (e.g. the hinge axis / slider direction), second column the secondary etc.

Implements TwoBodyConstraint.

GetCurrentAngle()

float HingeConstraint::GetCurrentAngle

(

)

const

Get the current rotation angle from the rest position.

GetLimitsMax()

float HingeConstraint::GetLimitsMax ( ) const

inline

GetLimitsMin()

float HingeConstraint::GetLimitsMin ( ) const

inline

GetLimitsSpringSettings() [1/2]

SpringSettings & HingeConstraint::GetLimitsSpringSettings ( )

inline

GetLimitsSpringSettings() [2/2]

const SpringSettings & HingeConstraint::GetLimitsSpringSettings ( ) const

inline

Update the limits spring settings.

GetLocalSpaceHingeAxis1()

Vec3 HingeConstraint::GetLocalSpaceHingeAxis1 ( ) const

inline

GetLocalSpaceHingeAxis2()

Vec3 HingeConstraint::GetLocalSpaceHingeAxis2 ( ) const

inline

GetLocalSpaceNormalAxis1()

Vec3 HingeConstraint::GetLocalSpaceNormalAxis1 ( ) const

inline

GetLocalSpaceNormalAxis2()

Vec3 HingeConstraint::GetLocalSpaceNormalAxis2 ( ) const

inline

GetLocalSpacePoint1()

Vec3 HingeConstraint::GetLocalSpacePoint1 ( ) const

inline

Get the attachment point for body 1 relative to body 1 COM (transform by Body::GetCenterOfMassTransform to take to world space)

GetLocalSpacePoint2()

Vec3 HingeConstraint::GetLocalSpacePoint2 ( ) const

inline

Get the attachment point for body 2 relative to body 2 COM (transform by Body::GetCenterOfMassTransform to take to world space)

GetMaxFrictionTorque()

float HingeConstraint::GetMaxFrictionTorque ( ) const

inline

GetMotorSettings() [1/2]

MotorSettings & HingeConstraint::GetMotorSettings ( )

inline

GetMotorSettings() [2/2]

const MotorSettings & HingeConstraint::GetMotorSettings ( ) const

inline

GetMotorState()

EMotorState HingeConstraint::GetMotorState ( ) const

inline

GetSubType()

virtual EConstraintSubType HingeConstraint::GetSubType ( ) const

inlineoverridevirtual

Get the sub type of a constraint.

Implements Constraint.

GetTargetAngle()

float HingeConstraint::GetTargetAngle ( ) const

inline

GetTargetAngularVelocity()

float HingeConstraint::GetTargetAngularVelocity ( ) const

inline

GetTotalLambdaMotor()

float HingeConstraint::GetTotalLambdaMotor ( ) const

inline

GetTotalLambdaPosition()

Vec3 HingeConstraint::GetTotalLambdaPosition ( ) const

inline

GetTotalLambdaRotation()

Vector< 2 > HingeConstraint::GetTotalLambdaRotation ( ) const

inline

GetTotalLambdaRotationLimits()

float HingeConstraint::GetTotalLambdaRotationLimits ( ) const

inline

HasLimits()

bool HingeConstraint::HasLimits ( ) const

inline

NotifyShapeChanged()

void HingeConstraint::NotifyShapeChanged ( const BodyID &  inBodyID, Vec3Arg  inDeltaCOM  )

overridevirtual

Notify the constraint that the shape of a body has changed and that its center of mass has moved by inDeltaCOM. Bodies don't know which constraints are connected to them so the user is responsible for notifying the relevant constraints when a body changes.

Parameters

inBodyID	ID of the body that has changed
inDeltaCOM	The delta of the center of mass of the body (shape->GetCenterOfMass() - shape_before_change->GetCenterOfMass())

Implements Constraint.

ResetWarmStart()

void HingeConstraint::ResetWarmStart ( )

overridevirtual

Notify the system that the configuration of the bodies and/or constraint has changed enough so that the warm start impulses should not be applied the next frame. You can use this function for example when repositioning a ragdoll through Ragdoll::SetPose in such a way that the orientation of the bodies completely changes so that the previous frame impulses are no longer a good approximation of what the impulses will be in the next frame. Calling this function when there are no big changes will result in the constraints being much 'softer' than usual so they are more easily violated (e.g. a long chain of bodies might sag a bit if you call this every frame).

Implements Constraint.

RestoreState()

void HingeConstraint::RestoreState ( StateRecorder &  inStream )

overridevirtual

Restoring state for replay.

Reimplemented from Constraint.

SaveState()

void HingeConstraint::SaveState ( StateRecorder &  inStream ) const

overridevirtual

Saving state for replay.

Reimplemented from Constraint.

SetLimits()

void HingeConstraint::SetLimits	(	float	inLimitsMin,
		float	inLimitsMax
	)

Update the rotation limits of the hinge, value in radians (see HingeConstraintSettings)

SetLimitsSpringSettings()

void HingeConstraint::SetLimitsSpringSettings ( const SpringSettings &  inLimitsSpringSettings )

inline

SetMaxFrictionTorque()

void HingeConstraint::SetMaxFrictionTorque ( float  inFrictionTorque )

inline

SetMotorState()

void HingeConstraint::SetMotorState ( EMotorState  inState )

inline

SetTargetAngle()

void HingeConstraint::SetTargetAngle ( float  inAngle )

inline

rad

SetTargetAngularVelocity()

void HingeConstraint::SetTargetAngularVelocity ( float  inAngularVelocity )

inline

rad/s

SetupVelocityConstraint()

void HingeConstraint::SetupVelocityConstraint ( float  inDeltaTime )

overridevirtual

Implements Constraint.

SolvePositionConstraint()

bool HingeConstraint::SolvePositionConstraint ( float  inDeltaTime, float  inBaumgarte  )

overridevirtual

Implements Constraint.

SolveVelocityConstraint()

bool HingeConstraint::SolveVelocityConstraint ( float  inDeltaTime )

overridevirtual

Implements Constraint.

WarmStartVelocityConstraint()

void HingeConstraint::WarmStartVelocityConstraint ( float  inWarmStartImpulseRatio )

overridevirtual

Implements Constraint.

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The documentation for this class was generated from the following files:

• Jolt/Physics/Constraints/HingeConstraint.h
• Jolt/Physics/Constraints/HingeConstraint.cpp