AnimationCore Namespace Reference

Classes
struct	FSplineIKSolverScratchArea

Functions
bool	ConstrainAngularRangeUsingEuler (FQuat &InOutQuatRotation, const FQuat &InRefRotation, const FVector &InLimitMinDegrees, const FVector &InLimitMaxDegrees)
FTransform	SolveConstraints (const FTransform &CurrentTransform, const FTransform &BaseTransform, const TArray< struct FTransformConstraint > &Constraints, const FGetGlobalTransform &OnGetGlobalTransform)
FQuat	SolveAim (const FTransform &CurrentTransform, const FVector &TargetPosition, const FVector &AimVector, bool bUseUpVector, const FVector &UpVector, float AimClampInDegree)
FTransform	SolveConstraints (const FTransform &CurrentTransform, const FTransform &CurrentParentTransform, const TArray< struct FConstraintData > &Constraints)
FQuat	QuatFromEuler (const FVector &XYZAnglesInDegrees, EEulerRotationOrder RotationOrder, bool bUseUEHandyness)
FVector	EulerFromQuat (const FQuat &Rotation, EEulerRotationOrder RotationOrder, bool bUseUEHandyness)
FVector	ChangeEulerRotationOrder (const FVector &XYZAnglesInDegrees, EEulerRotationOrder SourceRotationOrder, EEulerRotationOrder TargetRotationOrder, bool bUseUEHandyness)
bool	SolveCCDIK (TArray< FCCDIKChainLink > &InOutChain, const FVector &TargetPosition, float Precision, int32 MaxIteration, bool bStartFromTail, bool bEnableRotationLimit, const TArray< float > &RotationLimitPerJoints)
bool	SolveFabrik (TArray< FFABRIKChainLink > &InOutChain, const FVector &TargetPosition, double MaximumReach, double Precision, int32 MaxIterations)
void	SoftenIKEffectorPosition (const FVector &RootLocation, const float TotalChainLength, const float SoftLengthPercent, const float Alpha, FVector &InOutEffectorPosition)
void	SolveSplineIK (const TArray< FTransform > &BoneTransforms, const FInterpCurveVector &PositionSpline, const FInterpCurveQuat &RotationSpline, const FInterpCurveVector &ScaleSpline, const float TotalSplineAlpha, const float TotalSplineLength, const FFloatMapping &Twist, const float Roll, const float Stretch, const float Offset, const EAxis::Type BoneAxis, const FFindParamAtFirstSphereIntersection &FindParamAtFirstSphereIntersection, const TArray< FQuat > &BoneOffsetRotations, const TArray< float > &BoneLengths, const float OriginalSplineLength, TArray< FTransform > &OutBoneTransforms)
void	SolveTwoBoneIK (FTransform &InOutRootTransform, FTransform &InOutJointTransform, FTransform &InOutEndTransform, const FVector &JointTarget, const FVector &Effector, bool bAllowStretching, double StartStretchRatio, double MaxStretchScale)
void	SolveTwoBoneIK (FTransform &InOutRootTransform, FTransform &InOutJointTransform, FTransform &InOutEndTransform, const FVector &JointTarget, const FVector &Effector, double UpperLimbLength, double LowerLimbLength, bool bAllowStretching, double StartStretchRatio, double MaxStretchScale)
void	SolveTwoBoneIK (const FVector &RootPos, const FVector &JointPos, const FVector &EndPos, const FVector &JointTarget, const FVector &Effector, FVector &OutJointPos, FVector &OutEndPos, bool bAllowStretching, double StartStretchRatio, double MaxStretchScale)
void	SolveTwoBoneIK (const FVector &RootPos, const FVector &JointPos, const FVector &EndPos, const FVector &JointTarget, const FVector &Effector, FVector &OutJointPos, FVector &OutEndPos, double UpperLimbLength, double LowerLimbLength, bool bAllowStretching, double StartStretchRatio, double MaxStretchScale)

Function Documentation

ChangeEulerRotationOrder()

FVector AnimationCore::ChangeEulerRotationOrder	(	const FVector &	XYZAnglesInDegrees,
		EEulerRotationOrder	SourceRotationOrder,
		EEulerRotationOrder	TargetRotationOrder,
		bool	bUseUEHandyness = false
	)

Converts a euler rotation from one rotation order to another

ConstrainAngularRangeUsingEuler()

bool AnimationCore::ConstrainAngularRangeUsingEuler	(	FQuat &	InOutQuatRotation,
		const FQuat &	InRefRotation,
		const FVector &	InLimitMinDegrees,
		const FVector &	InLimitMaxDegrees
	)

EulerFromQuat()

FVector AnimationCore::EulerFromQuat	(	const FQuat &	Rotation,
		EEulerRotationOrder	RotationOrder = EEulerRotationOrder::ZYX,
		bool	bUseUEHandyness = false
	)

Converts a quaternion to a euler rotation represented by a vector of rotations in degrees and a rotation order bUseUEHandyness If True will use UE handyness with right handed X and Y angles left handed Z, if False all are left handed

QuatFromEuler()

FQuat AnimationCore::QuatFromEuler	(	const FVector &	XYZAnglesInDegrees,
		EEulerRotationOrder	RotationOrderr = EEulerRotationOrder::ZYX,
		bool	bUseUEHandyness = false
	)

Converts a euler rotation represented by a vector of rotations in degrees and a rotation order to a quaternion bUseUEHandyness If True will use UE handyness with right handed X and Y angles left handed Z, if False all are left handed

SoftenIKEffectorPosition()

void AnimationCore::SoftenIKEffectorPosition	(	const FVector &	RootLocation,
		const float	TotalChainLength,
		const float	SoftLengthPercent,
		const float	Alpha,
		FVector &	InOutEffectorPosition
	)

Soft IK

This modifies the effector position for a chain of joints being controlled by IK by making the effector softly approach full extension. It takes the desired effector position and adjusts it according to an exponential falloff as the effector approach the full length of the chain.

The technique used is described here: https://web.archive.org/web/20160610183037/https://softimageblog.com/archives/108

Parameters

RootLocation	The location of the bone at the root of the chain
TotalChainLength	The total length of the chain from root to tip, along the bones (not straight line).
SoftLengthPercent	The percentage of the chain length to begin softening the effector motion (typically set to 0.97)
Alpha	The amount of softness to apply (0 is none, 1 is full amount). Default is 1.
InOutEffectorPosition	The input position of the end effector. This is modified by this function to "soften" the IK.

SolveAim()

FQuat AnimationCore::SolveAim	(	const FTransform &	CurrentTransform,
		const FVector &	TargetPosition,
		const FVector &	AimVector,
		bool	bUseUpVector = false,
		const FVector &	UpVector = FVector::UpVector,
		float	AimClampInDegree = 0.f
	)

Aim solver

This solves new transform that aims at the target based on inputs

Parameters

CurrentTransform	Current Transform
TargetPosition	Target to look at
AimVector	Aim vector in Current Transform
bUseUpVector	Whether or not to use Up vector
UpVector	Up Vector in Current Transform if bUseUpVector is true
AimClampInDegree	Clamp cone around the AimVector

Returns

Delta Rotation to turn

SolveCCDIK()

bool AnimationCore::SolveCCDIK	(	TArray< FCCDIKChainLink > &	InOutChain,
		const FVector &	TargetPosition,
		float	Precision,
		int32	MaxIteration,
		bool	bStartFromTail,
		bool	bEnableRotationLimit,
		const TArray< float > &	RotationLimitPerJoints
	)

SolveConstraints() [1/2]

FTransform AnimationCore::SolveConstraints	(	const FTransform &	CurrentTransform,
		const FTransform &	BaseTransform,
		const TArray< FTransformConstraint > &	Constraints,
		const FGetGlobalTransform &	OnGetGlobalTransform
	)

Resolve Constraints based on input constraints data and current transform

Parameters

CurrentTransform	Current transform, based on BaseTransform
BaseTransform	Base transform of the current transform, where Constraint transform would be converted
Constraints	List of constraints to be used by this transform
OnGetGlobalTransform	Delegate to get transform data for constraints

Returns

resolved transform

SolveConstraints() [2/2]

FTransform AnimationCore::SolveConstraints	(	const FTransform &	CurrentTransform,
		const FTransform &	CurrentParentTransform,
		const TArray< FConstraintData > &	Constraints
	)

Resolve Constraints based on input constraints data and current transform

Parameters

CurrentTransform	Current transform, based on BaseTransform
BaseTransform	Base transform of the current transform, where Constraint transform would be converted
Constraints	List of constraints - should contains latest transform

Returns

resolved transform

SolveFabrik()

bool AnimationCore::SolveFabrik	(	TArray< FFABRIKChainLink > &	InOutChain,
		const FVector &	TargetPosition,
		double	MaximumReach,
		double	Precision,
		int32	MaxIteration
	)

Fabrik solver

This solves FABRIK

Parameters

Chain	Array of chain data
TargetPosition	Target for the IK
MaximumReach	Maximum Reach
Precision	Precision
MaxIteration	Number of Max Iteration

Returns

true if modified. False if not.

SolveSplineIK()

void AnimationCore::SolveSplineIK	(	const TArray< FTransform > &	BoneTransforms,
		const FInterpCurveVector &	PositionSpline,
		const FInterpCurveQuat &	RotationSpline,
		const FInterpCurveVector &	ScaleSpline,
		const float	TotalSplineAlpha,
		const float	TotalSplineLength,
		const FFloatMapping &	Twist,
		const float	Roll,
		const float	Stretch,
		const float	Offset,
		const EAxis::Type	BoneAxis,
		const FFindParamAtFirstSphereIntersection &	FindParamAtFirstSphereIntersection,
		const TArray< FQuat > &	BoneOffsetRotations,
		const TArray< float > &	BoneLengths,
		const float	OriginalSplineLength,
		TArray< FTransform > &	OutBoneTransforms
	)

SolveTwoBoneIK() [1/4]

void AnimationCore::SolveTwoBoneIK	(	const FVector &	RootPos,
		const FVector &	JointPos,
		const FVector &	EndPos,
		const FVector &	JointTarget,
		const FVector &	Effector,
		FVector &	OutJointPos,
		FVector &	OutEndPos,
		bool	bAllowStretching,
		double	StartStretchRatio,
		double	MaxStretchScale
	)

Two Bone IK

This handles two bone chain link excluding root bone. This will solve the solution for joint/end when given root, joint, end position (root->joint->end in the hierarchy) based on effector, joint target location This only solves for location, if you want to rotate them to face target, this doesn't do it for you

Parameters

RootPos	Root position
JointPos	Joint position
EndPos	End position
JointTarget	Joint Target position (where joint is facing while creating plane between joint pos, joint target, root pos(rotate-plane ik))
Effector	Effector position (target position)
OutJointPos	(out) adjusted joint pos
OutEndPos	(out) adjusted end pos
bAllowStretching	whether or not to allow stretching or not
StartStretchRatio	When should it start stretch -i.e. 1 means its own length without any stretch
MaxStretchScale	How much it can stretch to in ratio

SolveTwoBoneIK() [2/4]

void AnimationCore::SolveTwoBoneIK	(	const FVector &	RootPos,
		const FVector &	JointPos,
		const FVector &	EndPos,
		const FVector &	JointTarget,
		const FVector &	Effector,
		FVector &	OutJointPos,
		FVector &	OutEndPos,
		double	UpperLimbLength,
		double	LowerLimbLength,
		bool	bAllowStretching,
		double	StartStretchRatio,
		double	MaxStretchScale
	)

Two Bone IK

This handles two bone chain link excluding root bone. This will solve the solution for joint/end when given root, joint, end position (root->joint->end in the hierarchy) based on effector, joint target location This only solves for location, if you want to rotate them to face target, this doesn't do it for you

Parameters

RootPos	Root position
JointPos	Joint position
EndPos	End position
JointTarget	Joint Target position (where joint is facing while creating plane between joint pos, joint target, root pos(rotate-plane ik))
Effector	Effector position (target position)
OutJointPos	(out) adjusted joint pos
OutEndPos	(out) adjusted end pos
bAllowStretching	whether or not to allow stretching or not O
StartStretchRatio	When should it start stretch -i.e. 1 means its own length without any stretch
MaxStretchScale	How much it can stretch to in ratio

SolveTwoBoneIK() [3/4]

void AnimationCore::SolveTwoBoneIK	(	FTransform &	InOutRootTransform,
		FTransform &	InOutJointTransform,
		FTransform &	InOutEndTransform,
		const FVector &	JointTarget,
		const FVector &	Effector,
		bool	bAllowStretching,
		double	StartStretchRatio,
		double	MaxStretchScale
	)

Two Bone IK

This handles two bone chain link excluding root bone. This will solve the solution for joint/end when given root, joint, end position (root->joint->end in the hierarchy) based on effector, joint target location This only solves for location, if you want to rotate them to face target, this doesn't do it for you

Parameters

RootPos	Root position
JointPos	Joint position
EndPos	End position
JointTarget	Joint Target position (where joint is facing while creating plane between joint pos, joint target, root pos(rotate-plane ik))
Effector	Effector position (target position)
OutJointPos	(out) adjusted joint pos
OutEndPos	(out) adjusted end pos
bAllowStretching	whether or not to allow stretching or not
StartStretchRatio	When should it start stretch -i.e. 1 means its own length without any stretch
MaxStretchScale	How much it can stretch to in ratio

SolveTwoBoneIK() [4/4]

void AnimationCore::SolveTwoBoneIK	(	FTransform &	InOutRootTransform,
		FTransform &	InOutJointTransform,
		FTransform &	InOutEndTransform,
		const FVector &	JointTarget,
		const FVector &	Effector,
		double	UpperLimbLength,
		double	LowerLimbLength,
		bool	bAllowStretching,
		double	StartStretchRatio,
		double	MaxStretchScale
	)

Two Bone IK

This handles two bone chain link excluding root bone. This will solve the solution for joint/end when given root, joint, end position (root->joint->end in the hierarchy) based on effector, joint target location This only solves for location, if you want to rotate them to face target, this doesn't do it for you

Parameters

RootPos	Root position
JointPos	Joint position
EndPos	End position
JointTarget	Joint Target position (where joint is facing while creating plane between joint pos, joint target, root pos(rotate-plane ik))
Effector	Effector position (target position)
OutJointPos	(out) adjusted joint pos
OutEndPos	(out) adjusted end pos
bAllowStretching	whether or not to allow stretching or not
StartStretchRatio	When should it start stretch -i.e. 1 means its own length without any stretch
MaxStretchScale	How much it can stretch to in ratio