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TQuat

Floating point quaternion that can represent a rotation about an axis in 3-D space.

API > API/Runtime > API/Runtime/Core > API/Runtime/Core/Math

Inheritance Hierarchy

References

   
Module Core
Header /Engine/Source/Runtime/Core/Public/Math/MathFwd.h
Include #include "Math/MathFwd.h"
Source /Engine/Source/Runtime/Core/Public/Math/Quat.h

Syntax

template<typename T>  
struct TQuat

Remarks

Floating point quaternion that can represent a rotation about an axis in 3-D space. The X, Y, Z, W components also double as the Axis/Angle format.

Order matters when composing quaternions: C = A * B will yield a quaternion C that logically first applies B then A to any subsequent transformation (right first, then left). Note that this is the opposite order of FTransform multiplication.

Example: LocalToWorld = (LocalToWorld * DeltaRotation) will change rotation in local space by DeltaRotation. Example: LocalToWorld = (DeltaRotation * LocalToWorld) will change rotation in world space by DeltaRotation.

Variables

  Type Name Description
Public variable T W The quaternion's W-component.
Public variable T X The quaternion's X-component.
Public variable T Y The quaternion's Y-component.
Public variable T Z The quaternion's Z-component.

Constructors

  Type Name Description
Public function  

TQuat ()

 Default constructor (no initialization).
Public function   Creates and initializes a new quaternion, with the W component either 0 or 1.
Public function  

TQuat ( T V
)

 Initializes all elements to V
Public function  

TQuat ( const TRotator< T >& R
)

 Creates and initializes a new quaternion from the given rotator.
Public function  

TQuat ( const TMatrix< T >& M
)

 Creates and initializes a new quaternion from the given matrix.
Public function  

TQuat ( const TQuat< FArg >& From
)

 Conversion to other type.
Protected function  

TQuat ( const QuatVectorRegister& V
)

 Creates and initializes a new quaternion from the XYZW values in the given VectorRegister4Float.
Public function  

TQuat ( TVector< T > Axis,
T AngleRad
)

 Creates and initializes a new quaternion from the a rotation around the given axis.
Public function  

TQuat ( T InX,
T InY,
T InZ,
T InW
)

 Constructor.

Functions

  Type Name Description
Public function Const T

AngularDistance ( const TQuat< T >& Q
)

 Find the angular distance between two rotation quaternions (in radians)
Public function Static void

CalcTangents ( const TQuat< T >& PrevP,
const TQuat< T >& P,
const TQuat< T >& NextP,
T Tension,
TQuat< T >& OutTan
)

 Calculate tangents between given points
Public function Const bool Utility to check if there are any non-finite values (NaN or Inf) in this Quat.
Public function Const void

DiagnosticCheckNaN ( const TCHAR* Message
)

  
Public function Const void  
Public function void

EnforceShortestArcWith ( const TQuat< T >& OtherQuat
)

 Enforce that the delta between this Quaternion and another one represents the shortest possible rotation angle
Public function Const bool

Equals ( const TQuat< T >& Q,
T Tolerance
)

 Checks whether another Quaternion is equal to this, within specified tolerance.
Public function Static T

Error ( const TQuat< T >& Q1,
const TQuat< T >& Q2
)

 Error measure (angle) between two quaternions, ranged [0..1].
Public function Static T

ErrorAutoNormalize ( const TQuat< T >& A,
const TQuat< T >& B
)

 TQuat::Error with auto-normalization.
Public function Const TVector< T >

Euler ()

 Convert a Quaternion into floating-point Euler angles (in degrees).
Public function Const TQuat< T >

Exp ()

 Exp should really only be used after Log.
Public function Static TQuat< T >

FastBilerp ( const TQuat< T >& P00,
const TQuat< T >& P10,
const TQuat< T >& P01,
const TQuat< T >& P11,
T FracX,
T FracY
)

 Bi-Linear Quaternion interpolation. Result is NOT normalized.
Public function Static TQuat< T >

FastLerp ( const TQuat< T >& A,
const TQuat< T >& B,
const T Alpha
)

 Fast Linear Quaternion Interpolation. Result is NOT normalized.
Public function Static TQuat< T >

FindBetween ( const TVector< T >& Vector1,
const TVector< T >& Vector2
)

 Generates the 'smallest' (geodesic) rotation between two vectors of arbitrary length.
Public function Static TQuat< T >

FindBetweenNormals ( const TVector< T >& Normal1,
const TVector< T >& Normal2
)

 Generates the 'smallest' (geodesic) rotation between two normals (assumed to be unit length).
Public function Static TQuat< T >

FindBetweenVectors ( const TVector< T >& Vector1,
const TVector< T >& Vector2
)

 Generates the 'smallest' (geodesic) rotation between two vectors of arbitrary length.
Public function Const T Get the angle in radians of this quaternion
Public function Const TVector< T > Get the forward direction (X axis) after it has been rotated by this Quaternion.
Public function Const TVector< T > Get the right direction (Y axis) after it has been rotated by this Quaternion.
Public function Const TVector< T > Get the up direction (Z axis) after it has been rotated by this Quaternion.
Public function Const TVector< T > Get the forward direction (X axis) after it has been rotated by this Quaternion.
Public function Const TQuat< T >

GetNormalized ( T Tolerance
)

 Get a normalized copy of this quaternion. If it is too small, returns an identity quaternion.
Public function Const TVector< T > Get the right direction (Y axis) after it has been rotated by this Quaternion.
Public function Const TVector< T > Get the axis of rotation of the Quaternion.
Public function Const T

GetTwistAngle ( const TVector< T >& TwistAxis
)

 Get the twist angle (in radians) for a specified axis
Public function Const TVector< T > Get the up direction (Z axis) after it has been rotated by this Quaternion.
Public function Const bool

Identical ( const TQuat* Q,
const uint32 PortFlags
)

 Identical implementation for TQuat properties.
Public function bool

InitFromString ( const FString& InSourceString
)

 Initialize this TQuat from a FString.
Public function Const TQuat< T >

Inverse ()

 : Requires this quaternion to be normalized.
Public function Const bool

IsIdentity ( T Tolerance
)

 Checks whether this Quaternion is an Identity Quaternion. Assumes Quaternion tested is normalized.
Public function Const bool Return true if this quaternion is normalized.
Public function Const TQuat< T >

Log ()

  
Public function Static TQuat< T >

MakeFromEuler ( const TVector< T >& Euler
)

 Convert a vector of floating-point Euler angles (in degrees) into a Quaternion.
Public function Static TQuat< T >

MakeFromRotationVector ( const TVector< T >& RotationVector
)

 Constructs a quaternion corresponding to the rotation vector.
Public function Static TQuat< T >

MakeFromRotator ( const TRotator< T >& R
)

  
Public function Static TQuat< T >  
Public function bool

NetSerialize ( FArchive& Ar,
UPackageMap* Map,
bool& bOutSuccess
)

 Serializes the vector compressed for e.g. network transmission.
Public function void

Normalize ( T Tolerance
)

 Normalize this quaternion if it is large enough.
Public function Const TVector< T >

RotateVector ( TVector< T > V
)

 Rotate a vector by this quaternion.
Public function Const TRotator< T >

Rotator ()

 Forward declare all explicit specializations (in UnrealMath.cpp)
Public function bool  
Public function bool  
Public function Const T

Size ()

 Get the length of this quaternion.
Public function Const T Get the length squared of this quaternion.
Public function Static TQuat< T >

Slerp ( const TQuat< T >& Quat1,
const TQuat< T >& Quat2,
T Slerp
)

 Spherical interpolation. Will correct alignment. Result is normalized.
Public function Static TQuat< T >

Slerp_NotNormalized ( const TQuat< T >& Quat1,
const TQuat< T >& Quat2,
T Slerp
)

 Spherical interpolation. Will correct alignment. Result is NOT normalized.
Public function Static TQuat< T >

SlerpFullPath ( const TQuat< T >& quat1,
const TQuat< T >& quat2,
T Alpha
)

 Simpler Slerp that doesn't do any checks for 'shortest distance' etc.
Public function Static TQuat< T >

SlerpFullPath_NotNormalized ( const TQuat< T >& quat1,
const TQuat< T >& quat2,
T Alpha
)

 Simpler Slerp that doesn't do any checks for 'shortest distance' etc.
Public function Static TQuat< T >

Squad ( const TQuat< T >& quat1,
const TQuat< T >& tang1,
const TQuat< T >& quat2,
const TQuat< T >& tang2,
T Alpha
)

 Given start and end quaternions of quat1 and quat2, and tangents at those points tang1 and tang2, calculate the point at Alpha (between 0 and 1) between them.
Public function Static TQuat< T >

SquadFullPath ( const TQuat< T >& quat1,
const TQuat< T >& tang1,
const TQuat< T >& quat2,
const TQuat< T >& tang2,
T Alpha
)

 Simpler Squad that doesn't do any checks for 'shortest distance' etc.
Public function Const void

ToAxisAndAngle ( TVector< T >& Axis,
float& Angle
)

 Get the axis and angle of rotation of this quaternion
Public function Const void

ToAxisAndAngle ( TVector< T >& Axis,
double& Angle
)

  
Public function Const void

ToMatrix ( TMatrix< T >& Mat
)

 Get the TMatrix representation of this Quaternion and store it in Mat
Public function Const TMatrix< T > Get the TMatrix representation of this Quaternion.
Public function Const TVector< T > Get the rotation vector corresponding to this quaternion.
Public function Const FString Get a textual representation of the vector.
Public function Const void

ToSwingTwist ( const TVector< T >& InTwistAxis,
TQuat< T >& OutSwing,
TQuat< T >& OutTwist
)

 Get the swing and twist decomposition for a specified axis
Public function Const TVector< T >

UnrotateVector ( TVector< T > V
)

 Rotate a vector by the inverse of this quaternion.
Public function Const TVector< T >

Vector ()

 Convert a rotation into a unit vector facing in its direction.

Operators

  Type Name Description
Public function Const TQuat< T >

operator- ( const TQuat< T >& Q
)

 Gets the result of subtracting a Quaternion to this.
Public function Const TQuat< T > Negates the quaternion. Note that this represents the same rotation.
Public function Const bool

operator!= ( const TQuat< T >& Q
)

 Checks whether two quaternions are not identical.
Public function Const TQuat< T >

operator* ( const FArg Scale
)

 Get the result of scaling this quaternion.
Public function Const TMatrix< T >

operator* ( const TMatrix< T >& M
)

 Multiply this by a matrix.
Public function Const TVector< T >

operator* ( const TVector< T >& V
)

 Rotate a vector by this quaternion.
Public function Const TQuat< T >

operator* ( const TQuat< T >& Q
)

 Gets the result of multiplying this by another quaternion (this * Q).
Public function TQuat< T >

operator*= ( const FArg Scale
)

 Multiply this quaternion by a scaling factor.
Public function TQuat< T >

operator*= ( const TQuat< T >& Q
)

 Multiply this by a quaternion (this = this * Q).
Public function Const TQuat< T >

operator/ ( const FArg Scale
)

 Divide this quaternion by scale.
Public function TQuat< T >

operator/= ( const FArg Scale
)

 Divide this quaternion by scale.
Public function Const T

operator| ( const TQuat< T >& Q
)

 Calculates dot product of two quaternions.
Public function Const TQuat< T >

operator+ ( const TQuat< T >& Q
)

 Gets the result of adding a Quaternion to this.
Public function TQuat< T >

operator+= ( const TQuat< T >& Q
)

 Adds to this quaternion.
Public function TQuat< T >

operator-= ( const TQuat< T >& Q
)

 Subtracts another quaternion from this.
Public function Const bool

operator== ( const TQuat< T >& Q
)

 Checks whether two quaternions are identical.

Typedefs

Name Description
FReal Can't have a UE_REQUIRES in the declaration because of the forward declarations, so check for allowed types here.
QuatVectorRegister  

Constants

Name Description
Identity Identity quaternion.

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