Quaternion

Fields

double

_x

double

_y

double

_z

double

_w

const Quaternion

ZERO

const Quaternion

IDENTITY

Functions

SET_CID

Quaternion

Quaternion

Quaternion

Quaternion

~Quaternion

double

operator[]

double &

operator[]

Quaternion

operator+

Quaternion

operator-

Quaternion

operator-

void

operator+=

void

operator-=

Quaternion

operator*

Quaternion

operator*

void

operator*=

void

operator*=

Quaternion

operator/

void

operator/=

bool

operator==

bool

operator!=

double

GetLength

double

GetLength2

double

Normalize

double

Dot

void

Invert

void

Conjugate

void

Log

void

Exp

void

Slerp

void

Squad

void

InnerQuadrangle

void

SetRotationMatrix

void

GetRotationMatrix

void

SetAxisAngle

void

GetAxisAngle

void

Set

double

X

double

Y

double

Z

double

W

Detailed Description

class Quaternion : public RED::Object

Quaternion for graphical operations.

The quaternion is of the form q = x*i + y*j + z*k + w.

Public Functions

SET_CID (CID_class_REDQuaternion) IMPLEMENT_AS()
Quaternion()

Quaternion construction method.

Builds a unit quaternion ( 0, 0, 0, 1 ).

Quaternion(double iX, double iY, double iZ, double iW)

Constructor.

Parameters
  • iX – X dimension of the quaternion.

  • iY – Y dimension of the quaternion.

  • iZ – Z dimension of the quaternion.

  • iW – W dimension of the quaternion.

Quaternion(const float data[4])

construction for a four floats array.

Parameters

data – array containing the four floating-point vector values.

Quaternion(const double data[4])

construction for a four double array.

Parameters

data – array containing the four double precision floating-point vector values.

virtual ~Quaternion()

Destructor.

inline double operator[](unsigned int iIndex) const

Gets the n-th component of a quaternion.

Returns

The n-th component of the quaternion.

inline double &operator[](unsigned int iIndex)

Gets the n-th component of a quaternion in read-write mode.

Returns

A reference to the n-th component of the quaternion.

inline RED::Quaternion operator+(const RED::Quaternion &iSource) const

Addition operation.

Builds a new quaternion by the addition of two others.

Returns

the sum of the two input quaternions.

inline RED::Quaternion operator-(const RED::Quaternion &iRight) const

Subtraction operation.

Builds a new quaternion by the subtraction of two others.

Parameters

iRight – Right operand of the subtraction

Returns

the subtraction of the two input quaternions.

inline RED::Quaternion operator-() const

Returns the opposite of the quaternion.

Returns

-‘this’

inline void operator+=(const RED::Quaternion &iSource)

Increment operation.

Adds the iSource quaternion to ‘this’.

Parameters

iSource – Added term.

inline void operator-=(const RED::Quaternion &iSource)

Decrement operation.

Subtracts the iSource quaternion to ‘this’.

Parameters

iSource – Subtracted term.

inline RED::Quaternion operator*(double iScalar) const

Multiplies the components of a quaternion with a scalar.

Parameters

iScalar – Number to multiply the quaternion with.

Returns

The product of the quaternion with the scalar.

inline RED::Quaternion operator*(const RED::Quaternion &iRight) const

Multiplication of two vectors.

Parameters

iRightQuaternion to multiply to this.

Returns

The product of the two quaternions.

inline void operator*=(double iScalar)

Multiplies the components of the quaternion with a scalar.

Parameters

iScalar – Number to multiply the quaternion with.

inline void operator*=(const RED::Quaternion &iRight)

Multiplication of two quaternions.

Store in ‘this’ the result of the product of ‘this’ with iRight.

Parameters

iRightQuaternion to multiply to this.

inline RED::Quaternion operator/(double iScalar) const

Divides the components of a quaternion by a scalar.

Parameters

iScalar – Number to divide the quaternion by.

Returns

The division of the quaternion by the scalar.

inline void operator/=(double iScalar)

Divides the components of the quaternion by a scalar.

Parameters

iScalar – Number to divide the quaternion by.

inline bool operator==(const RED::Quaternion &iOther) const

Returns the result of an equality test between two quaternions.

Parameters

iOther – Reference to the quaternion to test with.

Returns

true if the two quaternions are identical, false otherwise.

inline bool operator!=(const RED::Quaternion &iOther) const

Returns the result of a difference test between two quaternions.

Parameters

iOther – Reference to the quaternion to test with.

Returns

true if the two quaternions are different, false otherwise.

inline double GetLength() const

Gets the length of the quaternion.

Returns

sqrt( x*x + y*y + z*z + w*w ).

inline double GetLength2() const

Gets the squared length of the quaternion.

Returns

The squared length of the quaternion.

inline double Normalize()

Normalizes the quaternion.

Calculates the length of the quaternion( x*x + y*y + z*z + w*w ) and divides the components by this length.

Returns

The length of the quaternion before normalization.

inline double Dot(const RED::Quaternion &iQ) const

Dot product of two quaternions.

Parameters

iQ – Right operand of the dot product.

Returns

The dot product of the two quaternions.

inline void Invert()

‘In-place’ inversion of ‘this’.

Computes the inverse of ‘this’, replacing the previous quaternion contents.

inline void Conjugate()

‘In-place’ conjugate of ‘this’.

Computes the conjugate of ‘this’, replacing the previous quaternion contents.

void Log(RED::Vector3 &oLog) const

Logarithmic quaternion function.

Parameters

oLog – Returned log of the quaternion.

void Exp(const RED::Vector3 &iValue)

Exponential quaternion function.

Parameters

iValue – Value to compute the exponential.

void Slerp(const RED::Quaternion &iQuatFrom, const RED::Quaternion &iQuatTo, double iWeight)

Computes the Spherical Linear Interpolation between two quaternions.

Parameters
  • iQuatFrom – Starting quaternion.

  • iQuatTo – Ending quaternion.

  • iWeight – weight value between 0 and 1.

void Squad(const RED::Quaternion &iQuatFrom, const RED::Quaternion &iQuatTo, const RED::Quaternion &iInnerQuadrangleFrom, const RED::Quaternion &iInnerQuadrangleTo, double iWeight)

Computes the Spherical Quadrangle Interpolation between two quaternions.

The inner quadrangles can be computed with RED::Quaternion::InnerQuadrangle.

For 2 quaternions ( i ) and ( i + 1 ) on a curve, the code is:

s1.InnerQuadrangle( q[ i - 1 ], q[ i ], q[ i + 1 ] );
s2.InnerQuadrangle( q[ i ], q[ i + 1 ], q[ i + 2 ] );
r.Squad( q[ i ], q[ i + 1 ], s1, s2, t );

Special case of the curve starting point 0:

s.InnerQuadrangle( q[ 0 ], q[ 1 ], q[ 2 ] );
r.Squad( q[ 0 ], q[ 1 ], q[ 0 ], s, t );

Special case of the curve ending point n:

s.InnerQuadrangle( q[ n - 2 ], q[ n - 1 ], q[ n ] );
r.Squad( q[ n - 1 ], q[ n ], s, q[ n ], t );

Parameters
  • iQuatFrom – Starting quaternion.

  • iQuatTo – Ending quaternion.

  • iInnerQuadrangleFrom – Inner quadrangle for the starting quaternion.

  • iInnerQuadrangleTo – Inner quadrangle for the ending quaternion.

  • iWeight – weight value between 0 and 1.

void InnerQuadrangle(const RED::Quaternion &iQuatBefore, const RED::Quaternion &iQuat, const RED::Quaternion &iQuatAfter)

Computes the inner quadrangle of a quaternion based on the two surrounding quaternions.

Parameters
  • iQuatBefore – The quaternion before.

  • iQuat – The quaternion for which to compute the inner quadrangle.

  • iQuatAfter – The quaternion after.

void SetRotationMatrix(const RED::Matrix &iRotationMatrix)

Sets the quaternion from a rotation matrix.

Parameters

iRotationMatrix – Rotation matrix to set the quaternion from.

void GetRotationMatrix(RED::Matrix &oRotationMatrix) const

Gets the rotation matrix from this quaternion.

Parameters

oRotationMatrix – Returned rotation matrix.

void SetAxisAngle(const RED::Vector3 &iAxis, double iAngle)

Sets the quaternion from an axis angle rotation .

Parameters
  • iAxis – The rotation axis.

  • iAngle – The rotation angle.

void GetAxisAngle(RED::Vector3 &oAxis, double &oAngle) const

Gets the axis angle rotation from this quaternion.

Parameters
  • oAxis – Returned rotation axis.

  • oAngle – Returned rotation angle.

inline void Set(double iX, double iY, double iZ, double iW)

Sets the four component of a quaternion.

Parameters
  • iX – First component.

  • iY – Second component.

  • iZ – Third component.

  • iW – Fourth component.

inline double X() const
Returns

The X dimension of the quaternion.

inline double Y() const
Returns

The Y dimension of the quaternion.

inline double Z() const
Returns

The Z dimension of the quaternion.

inline double W() const
Returns

The W dimension of the quaternion.

Public Members

double _x

X dimension of the vector.

double _y

Y dimension of the vector.

double _z

Z dimension of the vector.

double _w

W dimension of the vector.

Public Static Attributes

static const RED::Quaternion ZERO

Zero quaternion.

static const RED::Quaternion IDENTITY

Identity quaternion.