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> Unreal Engine API Reference > Runtime > Engine > PhysicsEngine > FConstraintInstance

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FConstraintInstance

Container for a physics representation of an object.

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References

Module	Engine
Header	/Engine/Source/Runtime/Engine/Classes/PhysicsEngine/ConstraintInstance.h
Include	#include "PhysicsEngine/ConstraintInstance.h"

Syntax

struct FConstraintInstance

Remarks

Container for a physics representation of an object.

Variables

	Name	Description
FRotator	AngularRotationOffset	Specifies the angular offset between the two frames of reference.
float	AverageMass
uint32: 1	bScaleLinearLimits	If true, linear limits scale using the absolute min of the 3d scale of the owning component
FName	ConstraintBone1	Name of first bone (body) that this constraint is connecting.
FName	ConstraintBone2	Name of second bone (body) that this constraint is connecting.
FPhysicsConstra...	ConstraintHandle	Internal physics constraint representation.
int32	ConstraintIndex	Indicates position of this constraint within the array in SkeletalMeshComponent.
FName	JointName	Name of bone that this joint is associated with.
FPhysScene *...	PhysScene
FPhysxUserData	PhysxUserData
FVector	Pos1	Location of constraint in Body1 reference frame (usually the "child" body for skeletal meshes).
FVector	Pos2	Location of constraint in Body2 reference frame (usually the "parent" body for skeletal meshes).
FVector	PriAxis1	Primary (twist) axis in Body1 reference frame.
FVector	PriAxis2	Primary (twist) axis in Body2 reference frame.
FConstraintProf...	ProfileInstance	Constraint Data (properties easily swapped at runtime based on different constraint profiles)
FVector	SecAxis1	Seconday axis in Body1 reference frame. Orthogonal to PriAxis1.
FVector	SecAxis2	Seconday axis in Body2 reference frame. Orthogonal to PriAxis2.

Constructors

	Name	Description
	FConstraintInstance()	Constructor

Functions

	Name	Description
FConstraintI...	Alloc()
void	CopyConstraintGeometryFrom ( const FConstraintInstance* Fro... )
void	CopyConstraintParamsFrom ( const FConstraintInstance* Fro... )
void	CopyProfilePropertiesFrom ( const FConstraintProfileProperties ... )	Copies behavior properties from the given profile.
void	DisableParentDominates()
void	DisableProjection()	Turn off linear and angular projection
void	DrawConstraint ( FPrimitiveDrawInterface* PDI, float Scale, float LimitDrawScale, bool bDrawLimits, bool bDrawSelected, const FTransform& Con1Frame, const FTransform& Con2Frame, bool bDrawAsPoint )
void	DrawConstraint ( int32 ViewIndex, FMeshElementCollector& Collector, float Scale, float LimitDrawScale, bool bDrawLimits, bool bDrawSelected, const FTransform& Con1Frame, const FTransform& Con2Frame, bool bDrawAsPoint )
void	EnableParentDominates()	Enable/Disable parent dominates (meaning the parent body cannot be be affected at all by a child)
void	EnableProjection()	Turn on linear and angular projection
void	Free ( FConstraintInstance* Ptr )	Hacks to easily get zeroed memory for special case when we don't use GC.
float	GetAngularSwing1Limit()	Gets the cone limit swing1 angle in degrees
EAngularCons...	GetAngularSwing1Motion()	Gets the motion type for the swing1 of the cone constraint
float	GetAngularSwing2Limit()	Gets the cone limit swing2 angle in degrees
EAngularCons...	GetAngularSwing2Motion()	Gets the motion type for the swing2 of the cone constraint
float	GetAngularTwistLimit()	Gets the twist limit angle in degrees
EAngularCons...	GetAngularTwistMotion()	Gets the motion type for the twist of the cone constraint
void	GetConstraintForce ( FVector& OutLinearForce, FVector& OutAngularForce )	Retrieve the constraint force most recently applied to maintain this constraint. Returns 0 forces if the constraint is not initialized or broken.
FVector	GetConstraintLocation()	Get the position of this constraint in world space.
float	GetCurrentSwing1()	The current swing1 of the constraint.
float	GetCurrentSwing2()	The current swing2 of the constraint.
float	GetCurrentTwist()	The current twist of the constraint.
bool	GetIsSoftLinearLimit()	Whether the linear limits are soft (only if at least one axis if Limited)
bool	GetIsSoftSwingLimit()	Whether the swing limits are soft (only available if swing1 and/or swing2 is Limited)
bool	GetIsSoftTwistLimit()	Whether the twist limits are soft (only available if twist is Limited)
float	GetLastKnownScale()
float	GetLinearLimit()	Gets the linear limit size
ELinearConst...	GetLinearXMotion()	Gets the motion type for the linear X-axis limit.
ELinearConst...	GetLinearYMotion()	Gets the motion type for the linear Y-axis limit.
ELinearConst...	GetLinearZMotion()	Gets the motion type for the linear Z-axis limit.
const FPhysi...	GetPhysicsConstraintRef()	Get underlying physics engine constraint
FTransform	GetRefFrame ( EConstraintFrame::Type Frame )	Get component ref frame.
float	GetSoftLinearLimitDamping()	Linear damping if the constraint is set to use soft linear limits
float	GetSoftLinearLimitStiffness()	Linear stiffness if the constraint is set to use soft linear limits
float	GetSoftSwingLimitDamping()	Swing damping if the constraint is set to use soft limits
float	GetSoftSwingLimitStiffness()	Swing stiffness if the constraint is set to use soft limits
float	GetSoftTwistLimitDamping()	Twist damping if the constraint is set to use soft limits
float	GetSoftTwistLimitStiffness()	Twist stiffness if the constraint is set to use soft limits
void	GetUsedMaterials ( TArray< UMaterialInterface* > ... )
void	InitConstraint ( FBodyInstance* Body1, FBodyInstance* Body2, float Scale, UObject* DebugOwner, FOnConstraintBroken InConstraintBro... )	Create physics engine constraint.
void	InitConstraint_AssumesLocked ( const FPhysicsActorHandle& ActorRe..., const FPhysicsActorHandle& ActorRe..., float InScale, FOnConstraintBroken InConstraintBro... )	Create physics engine constraint using physx actors.
bool	IsAngularOrientationDriveEnabled()	Whether the angular orientation drive is enabled
bool	IsAngularVelocityDriveEnabled()	Whether the angular velocity drive is enabled
bool	IsBroken()	Retrieve the status of constraint being broken.
bool	IsCollisionDisabled()	Whether collision is currently disabled
bool	IsLinearPositionDriveEnabled()	Whether the linear position drive is enabled
bool	IsLinearVelocityDriveEnabled()	Whether the linear velocity drive is enabled
bool	IsParentDominatesEnabled()	Whether parent domination is enabled (meaning the parent body cannot be be affected at all by a child)
bool	IsProjectionEnabled()	Whether projection is enabled for this constraint
bool	IsTerminated()	Whether the physics engine constraint has been terminated
bool	IsValidConstraintInstance()	See if this constraint is valid.
void	PostSerialize ( const FArchive& Ar )
bool	Serialize ( FArchive& Ar )
void	SetAngularBreakable ( bool bInAngularBreakable, float InAngularBreakThreshold )	Sets the Angular Breakable properties
void	SetAngularDOFLimitScale ( float InSwing1LimitScale, float InSwing2LimitScale, float InTwistLimitScale )	Scale Angular Limit Constraints (as defined in RB_ConstraintSetup).
void	SetAngularDriveMode ( EAngularDriveMode::Type DriveMode )	Set the angular drive mode
void	SetAngularDriveParams ( float InSpring, float InDamping, float InForceLimit )	Set the angular drive's strength parameters Function for setting angular motor parameters.
void	SetAngularOrientationTarget ( const FQuat& InPosTarget )	Set the angular drive's orientation target Function for setting target angular position.
void	SetAngularSwing1Limit ( EAngularConstraintMotion MotionType, float InSwing1LimitAngle )	Sets the Angular Swing1 Motion Type
void	SetAngularSwing1Motion ( EAngularConstraintMotion MotionType )	Sets the cone limit's swing1 motion type
void	SetAngularSwing2Limit ( EAngularConstraintMotion MotionType, float InSwing2LimitAngle )	Sets the Angular Swing2 Motion Type
void	SetAngularSwing2Motion ( EAngularConstraintMotion MotionType )	Sets the cone limit's swing2 motion type
void	SetAngularTwistLimit ( EAngularConstraintMotion MotionType, float InTwistLimitAngle )	Sets the Angular Twist Motion Type
void	SetAngularTwistMotion ( EAngularConstraintMotion MotionType )	Sets the twist limit's motion type
void	SetAngularVelocityDriveSLERP ( bool bInEnableSLERP )	Set whether the SLERP angular velocity drive is enabled.
void	SetAngularVelocityDriveTwistAndSwing ( bool bInEnableTwistDrive, bool bInEnableSwingDrive )	Set which twist and swing angular velocity drives are enabled.
void	SetAngularVelocityTarget ( const FVector& InVelTarget )	Set the angular drive's angular velocity target Function for setting target angular velocity.
void	SetConstraintBrokenDelegate ( FOnConstraintBroken InConstraintBro... )	Set teh constraint broken delegate.
void	SetDisableCollision ( bool InDisableCollision )	Set whether jointed actors can collide with each other
void	SetLinearBreakable ( bool bInLinearBreakable, float InLinearBreakThreshold )	Sets the Linear Breakable properties
void	SetLinearDriveParams ( float InPositionStrength, float InVelocityStrength, float InForceLimit )	Set the linear drive's strength parameters Function for setting linear motor parameters.
void	SetLinearLimitSize ( float NewLimitSize )	Allows you to dynamically change the size of the linear limit 'sphere'.
void	SetLinearPositionDrive ( bool bEnableXDrive, bool bEnableYDrive, bool bEnableZDrive )	Set which linear position drives are enabled
void	SetLinearPositionTarget ( const FVector& InPosTarget )	Set the linear drive's target position position Function for setting linear position target.
void	SetLinearVelocityDrive ( bool bEnableXDrive, bool bEnableYDrive, bool bEnableZDrive )	Set which linear velocity drives are enabled
void	SetLinearVelocityTarget ( const FVector& InVelTarget )	Set the linear drive's target velocity Function for setting linear velocity target.
void	SetLinearXLimit ( ELinearConstraintMotion ConstraintT..., float InLinearLimitSize )	Sets the LinearX Motion Type and the limit distance (Note distance is the same for all 3 axes)
void	SetLinearXMotion ( ELinearConstraintMotion ConstraintT... )	Sets the Linear XMotion type
void	SetLinearYLimit ( ELinearConstraintMotion ConstraintT..., float InLinearLimitSize )	Sets the LinearY Motion Type and the limit distance (Note distance is the same for all 3 axes)
void	SetLinearYMotion ( ELinearConstraintMotion ConstraintT... )	Sets the Linear YMotion type
void	SetLinearZLimit ( ELinearConstraintMotion ConstraintT..., float InLinearLimitSize )	Sets the LinearZ Motion Type and the limit distance (Note distance is the same for all 3 axes)
void	SetLinearZMotion ( ELinearConstraintMotion ConstraintT... )	Sets the Linear ZMotion type
void	SetOrientationDriveSLERP ( bool bInEnableSLERP )	Set whether the SLERP angular position drive is enabled.
void	SetOrientationDriveTwistAndSwing ( bool bInEnableTwistDrive, bool bInEnableSwingDrive )	Set which twist and swing orientation drives are enabled.
void	SetRefFrame ( EConstraintFrame::Type Frame, const FTransform& RefFrame )	Pass in reference frame in. If the constraint is currently active, this will set its active local pose. Otherwise the change will take affect in InitConstraint.
void	SetRefOrientation ( EConstraintFrame::Type Frame, const FVector& PriAxis, const FVector& SecAxis )	Pass in reference orientation in (maintains reference position). If the constraint is currently active, this will set its active local pose. Otherwise the change will take affect in InitConstraint.
void	SetRefPosition ( EConstraintFrame::Type Frame, const FVector& RefPosition )	Pass in reference position in (maintains reference orientation). If the constraint is currently active, this will set its active local pose. Otherwise the change will take affect in InitConstraint.
void	TermConstraint()	Terminate physics engine constraint
void	UpdateAngularLimit()	Refreshes the physics engine joint's angular limits.
void	UpdateLinearLimit()	Refreshes the physics engine joint's linear limits.

Deprecated Variables

	Name	Description
float	AngularBreakThreshold_DEPRECATED
float	AngularDriveDamping_DEPRECATED
float	AngularDriveForceLimit_DEPRECATED
TEnumAsByte< EA...	AngularDriveMode_DEPRECATED
float	AngularDriveSpring_DEPRECATED
FRotator	AngularOrientationTarget_DEPRECATED
FQuat	AngularPositionTarget_DEPRECATED
TEnumAsByte< en...	AngularSwing1Motion_DEPRECATED
TEnumAsByte< en...	AngularSwing2Motion_DEPRECATED
TEnumAsByte< en...	AngularTwistMotion_DEPRECATED
FVector	AngularVelocityTarget_DEPRECATED
uint32: 1	bAngularBreakable_DEPRECATED
uint32: 1	bAngularOrientationDrive_DEPRECATED
uint32: 1	bAngularSlerpDrive_DEPRECATED
uint32: 1	bAngularVelocityDrive_DEPRECATED
uint32: 1	bDisableCollision_DEPRECATED	DEPRECATED Most of these properties have moved inside the ProfileInstance member (FConstraintProfileProperties struct)
uint32: 1	bEnableProjection_DEPRECATED
uint32: 1	bLinearBreakable_DEPRECATED
uint32: 1	bLinearLimitSoft_DEPRECATED
uint32: 1	bLinearPositionDrive_DEPRECATED
uint32: 1	bLinearVelocityDrive_DEPRECATED
uint32: 1	bSwingLimitSoft_DEPRECATED
uint32: 1	bSwingPositionDrive_DEPRECATED
uint32: 1	bSwingVelocityDrive_DEPRECATED
uint32: 1	bTwistLimitSoft_DEPRECATED
uint32: 1	bTwistPositionDrive_DEPRECATED
uint32: 1	bTwistVelocityDrive_DEPRECATED
float	LinearBreakThreshold_DEPRECATED
float	LinearDriveDamping_DEPRECATED
float	LinearDriveForceLimit_DEPRECATED
float	LinearDriveSpring_DEPRECATED
float	LinearLimitDamping_DEPRECATED
float	LinearLimitSize_DEPRECATED
float	LinearLimitStiffness_DEPRECATED
FVector	LinearPositionTarget_DEPRECATED
FVector	LinearVelocityTarget_DEPRECATED
TEnumAsByte< en...	LinearXMotion_DEPRECATED
TEnumAsByte< en...	LinearYMotion_DEPRECATED
TEnumAsByte< en...	LinearZMotion_DEPRECATED
float	ProjectionAngularTolerance_DEPRECATED
float	ProjectionLinearTolerance_DEPRECATED
float	Swing1LimitAngle_DEPRECATED
float	Swing2LimitAngle_DEPRECATED
float	SwingLimitDamping_DEPRECATED
float	SwingLimitStiffness_DEPRECATED
float	TwistLimitAngle_DEPRECATED
float	TwistLimitDamping_DEPRECATED
float	TwistLimitStiffness_DEPRECATED

Deprecated Functions

		Name	Description
	void	SetAngularPositionDrive ( bool bInEnableSwingDrive, bool bInEnableTwistDrive )	Please call SetOrientationDriveTwistAndSwing. Note the order of bools is reversed (Make sure to pass Twist and then Swing)
	void	SetAngularVelocityDrive ( bool bInEnableSwingDrive, bool bInEnableTwistDrive )	Please call SetAngularVelocityDriveTwistAndSwing. Note the order of bools is reversed (Make sure to pass Twist and then Swing)

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