nkMaths::Quaternion Class Reference

A quaternion, symbolizing rotations as a 4D vector. More...

Public Member Functions
	Quaternion () noexcept
	Quaternion (float x, float y, float z, float w) noexcept
	Quaternion (const Vector &axis, float angle) noexcept
	Quaternion (const Vector &eulerAngles) noexcept
	Quaternion (const Vector &a, const Vector &b) noexcept
	Quaternion (const Matrix &mat) noexcept
	Quaternion (const Quaternion &other) noexcept
Vector	getAsEulerAngles () const
Vector	getAsAxisAngle () const
Quaternion &	setFromAxisAngle (const Vector &axis, float angle)
Quaternion &	setFromEuler (const Vector &angles)
Quaternion &	setFromRotationBetween (const Vector &a, const Vector &b)
Quaternion &	setFromOrientationMatrix (const Matrix &mat)
Quaternion &	setFromTransformationMatrix (const Matrix &mat)
Vector	transform (const Vector &vector) const
Vector &	apply (Vector &vector) const
nkMemory::String	toString () const
Quaternion &	fromString (nkMemory::StringView str)
Quaternion &	operator= (const Quaternion &other) noexcept
Vector	operator* (const Vector &other) const
Quaternion	operator* (const Quaternion &other) const
void	operator*= (const Quaternion &other)
bool	operator== (const Quaternion &other) const

Public Attributes
float	_x
	X component of the quaternion.
float	_y
	Y component of the quaternion.
float	_z
	Z component of the quaternion.
float	_w
	W component of the quaternion.

Detailed Description

A quaternion, symbolizing rotations as a 4D vector.

The equation for the quaternion is considered as : xi + yj + zk + w.

Constructor & Destructor Documentation

Quaternion() [1/7]

nkMaths::Quaternion::Quaternion ( )

noexcept

Default constructor. Defaults to (0, 0, 0, 1), encoding no rotation.

Quaternion() [2/7]

nkMaths::Quaternion::Quaternion ( float  x, float  y, float  z, float  w  )

noexcept

Filling constructor.

Parameters

x	The x component.
y	The y component.
z	The z component.
w	The w component.

Quaternion() [3/7]

nkMaths::Quaternion::Quaternion ( const Vector &  axis, float  angle  )

noexcept

Axis angle constructor.

Parameters

axis	The axis of rotation to consider.
angle	The angle around this axis, in radians.

Quaternion() [4/7]

nkMaths::Quaternion::Quaternion ( const Vector &  eulerAngles )

noexcept

Euler angles constructor.

Parameters

eulerAngles

The euler angles, considering rotation in ZYX (Yaw-Pitch-Roll) order.

Quaternion() [5/7]

nkMaths::Quaternion::Quaternion ( const Vector &  a, const Vector &  b  )

noexcept

Direction to direction constructor.

Parameters

a	The vector to rotate from.
b	The vector to rotate to.

Quaternion() [6/7]

nkMaths::Quaternion::Quaternion ( const Matrix &  mat )

noexcept

Matrix constructor.

Parameters

mat	The matrix from which to extract the rotation.

Quaternion() [7/7]

nkMaths::Quaternion::Quaternion ( const Quaternion &  other )

noexcept

Copy constructor.

Parameters

other

The quaternion to copy.

Member Function Documentation

getAsEulerAngles()

Vector nkMaths::Quaternion::getAsEulerAngles

(

)

const

Returns

The quaternion translated as euler angles, encoded with ZYX ordering (Yaw-Pitch-Roll).

getAsAxisAngle()

Vector nkMaths::Quaternion::getAsAxisAngle

(

)

const

Returns

The quaternion translated as an axis angle vector (xyz axis, w angle in radians).

setFromAxisAngle()

Quaternion& nkMaths::Quaternion::setFromAxisAngle	(	const Vector &	axis,
		float	angle
	)

Sets the quaternion from an axis and angle pair.

Parameters

axis	The axis to rotate around.
angle	The angle to rotate, in radians.

Returns

Reference over caller.

setFromEuler()

Quaternion& nkMaths::Quaternion::setFromEuler

(

const Vector &

angles

)

Sets the quaternion from euler angles.

Parameters

angles

The euler angles to translate, considering rotation in ZYX (Yaw-Pitch-Roll) order.

Returns

Reference over caller.

setFromRotationBetween()

Quaternion& nkMaths::Quaternion::setFromRotationBetween	(	const Vector &	a,
		const Vector &	b
	)

Sets the quaternion from the rotation needed to rotate from one direction to another.

Parameters

a	The vector to rotate from.
b	The vector to rotate to.

Returns

Reference over caller.

setFromOrientationMatrix()

Quaternion& nkMaths::Quaternion::setFromOrientationMatrix

(

const Matrix &

mat

)

Sets the quaternion from a rotation matrix.

Parameters

mat	The matrix to extract the rotation from.

Returns

Reference over caller.

setFromTransformationMatrix()

Quaternion& nkMaths::Quaternion::setFromTransformationMatrix

(

const Matrix &

mat

)

Sets the quaternion from a full transformation matrix.

Parameters

mat	The matrix to extract the rotation from.

Returns

Reference over caller.

transform()

Vector nkMaths::Quaternion::transform

(

const Vector &

vector

)

const

Rotates a vector, by copying it and returning it. Another way to express q * v.

Parameters

vector

The vector to rotate.

Returns

The vector once rotated.

apply()

Vector& nkMaths::Quaternion::apply

(

Vector &

vector

)

const

Rotates a vector, by altering the vector parameter. Another way to express q *= v.

Parameters

vector

The vector to rotate.

Returns

The vector given, once rotated.

toString()

nkMemory::String nkMaths::Quaternion::toString

(

)

const

Returns

The quaternion expressed as a string, formatted as "x, y, z, w".

fromString()

Quaternion& nkMaths::Quaternion::fromString

(

nkMemory::StringView

str

)

Parse components from a string. Format is "x,y,z,w".

Parameters

str	The string to parse.

Returns

The updated quaternion instance.

operator=()

Quaternion& nkMaths::Quaternion::operator= ( const Quaternion &  other )

noexcept

Assignment operator.

Parameters

other

The quaternion to assign.

operator*() [1/2]

Vector nkMaths::Quaternion::operator*

(

const Vector &

other

)

const

Multiplication operator.

Parameters

other

The vector to apply the quaternion to.

Returns

The vector, rotated by the quaternion.

operator*() [2/2]

Quaternion nkMaths::Quaternion::operator*

(

const Quaternion &

other

)

const

Multiplication operator.

Parameters

other

The quaternion to multiply with.

Returns

A quaternion being the result of the multiplication of both quaternions.

operator*=()

void nkMaths::Quaternion::operator*=

(

const Quaternion &

other

)

Multiplication and assignment operator.

Parameters

other

The quaternion to multiply with.

operator==()

bool nkMaths::Quaternion::operator==

(

const Quaternion &

other

)

const

Comparison operator.

Parameters

other

The quaternion to compare with.

Returns

Whether the quaternions have the same component values (true) or not (false).

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

• Documentation/Headers/NilkinsMaths/Algebra/Quaternion.h