PLMath::Matrix3x4 Class Reference

3x4 matrix More...

#include <Matrix3x4.h>

List of all members.

Public Member Functions
	Matrix3x4 ()
	Default constructor setting an identity matrix.
	Matrix3x4 (const float fS[])
PLMATH_API	Matrix3x4 (const Matrix3x3 &mM)
	Matrix3x4 (const Matrix3x4 &mM)
PLMATH_API	Matrix3x4 (const Matrix4x4 &mM)
	Matrix3x4 (float fXX, float fXY, float fXZ, float fXW, float fYX, float fYY, float fYZ, float fYW, float fZX, float fZY, float fZZ, float fZW)
	~Matrix3x4 ()
PLMATH_API bool	operator== (const Matrix3x4 &mM) const
PLMATH_API bool	operator!= (const Matrix3x4 &mM) const
PLMATH_API bool	CompareScale (const Matrix3x4 &mM, float fEpsilon=Math::Epsilon) const
PLMATH_API bool	CompareTranslation (const Matrix3x4 &mM, float fEpsilon=Math::Epsilon) const
PLMATH_API bool	CompareRotation (const Matrix3x4 &mM, float fEpsilon=Math::Epsilon) const
Matrix3x4 &	operator= (const float fS[])
PLMATH_API Matrix3x4 &	operator= (const Matrix3x3 &mM)
Matrix3x4 &	operator= (const Matrix3x4 &mM)
PLMATH_API Matrix3x4 &	operator= (const Matrix4x4 &mM)
Matrix3x4	operator+ (const Matrix3x4 &mM) const
void	operator+= (const Matrix3x4 &mM)
Matrix3x4	operator- () const
Matrix3x4	operator- (const Matrix3x4 &mM) const
void	operator-= (const Matrix3x4 &mM)
Matrix3x4	operator* (float fS) const
void	operator*= (float fS)
Vector2	operator* (const Vector2 &vV) const
Vector3	operator* (const Vector3 &vV) const
Vector4	operator* (const Vector4 &vV) const
PLMATH_API Matrix3x4	operator* (const Matrix3x4 &mM) const
PLMATH_API Matrix3x4	operator* (const Matrix4x4 &mM) const
void	operator*= (const Matrix3x4 &mM)
PLMATH_API void	operator*= (const Matrix4x4 &mM)
Matrix3x4	operator/ (float fS) const
void	operator/= (float fS)
float	operator[] (int nIndex) const
float &	operator[] (int nIndex)
float	operator() (PLCore::uint32 nRow=0, PLCore::uint32 nColumn=0) const
float &	operator() (PLCore::uint32 nRow=0, PLCore::uint32 nColumn=0)
	operator float * ()
	operator const float * () const
bool	IsZero () const
	Returns whether or not this matrix is the zero matrix using an epsilon environment.
bool	IsTrueZero () const
	Returns whether or not this matrix is truly the zero matrix.
void	SetZero ()
	Sets a zero matrix.
bool	IsIdentity () const
	Returns whether or not this matrix is the identity matrix using an epsilon environment.
bool	IsTrueIdentity () const
	Returns whether or not this matrix is truly the identity matrix.
void	SetIdentity ()
	Sets an identity matrix.
PLMATH_API void	Set (float fXX, float fXY, float fXZ, float fXW, float fYX, float fYY, float fYZ, float fYW, float fZX, float fZY, float fZZ, float fZW)
	Sets the elements of the matrix.
Vector4	GetRow (PLCore::uint8 nRow) const
	Returns a requested row.
void	SetRow (PLCore::uint8 nRow, const Vector4 &vRow)
	Sets a row.
Vector3	GetColumn (PLCore::uint8 nColumn) const
	Returns a requested column.
void	SetColumn (PLCore::uint8 nColumn, const Vector3 &vColumn)
	Sets a column.
bool	IsSymmetric () const
	Returns true if the matrix is symmetric.
bool	IsOrthogonal () const
	Returns true if this matrix is orthogonal.
bool	IsRotationMatrix () const
	Returns true if this matrix is a rotation matrix.
bool	IsRotationTranslationMatrix () const
	Returns true if this matrix is a rotation and translation matrix.
float	GetTrace () const
	Returns the trace of the matrix.
float	GetDeterminant () const
	Returns the determinant of the matrix.
void	Transpose ()
	Transpose this matrix.
Matrix3x4	GetTransposed () const
	Returns the transposed matrix.
PLMATH_API bool	Invert ()
	Inverts the matrix.
PLMATH_API Matrix3x4	GetInverted () const
	Returns the inverse of the matrix.
PLMATH_API Vector3	RotateVector (float fX, float fY, float fZ, bool bUniformScale=false) const
	Rotates a vector.
PLMATH_API Vector3	RotateVector (const Vector3 &vV, bool bUniformScale=false) const
	Rotates a vector.
void	SetScaleMatrix (float fX, float fY, float fZ)
	Sets a scale matrix.
void	SetScaleMatrix (const Vector3 &vV)
PLMATH_API void	GetScale (float &fX, float &fY, float &fZ) const
	Extracts the scale vector from the matrix as good as possible.
Vector3	GetScale () const
void	GetScale (float fV[]) const
void	SetTranslationMatrix (float fX, float fY, float fZ)
	Sets a translation matrix.
void	SetTranslationMatrix (const Vector3 &vV)
void	GetTranslation (float &fX, float &fY, float &fZ) const
Vector3	GetTranslation () const
void	GetTranslation (float fV[]) const
void	SetTranslation (float fX=0.0f, float fY=0.0f, float fZ=0.0f)
void	SetTranslation (const Vector3 &vV)
void	SetTranslation (const float fV[])
PLMATH_API void	FromEulerAngleX (float fAngleX)
	Sets an x axis rotation matrix by using one given Euler angle.
PLMATH_API void	FromEulerAngleY (float fAngleY)
	Sets an y axis rotation matrix by using one given Euler angle.
PLMATH_API void	FromEulerAngleZ (float fAngleZ)
	Sets an z axis rotation matrix by using one given Euler angle.
PLMATH_API void	ToAxisAngle (float &fX, float &fY, float &fZ, float &fAngle) const
	Returns a rotation matrix as a selected axis and angle.
PLMATH_API void	FromAxisAngle (float fX, float fY, float fZ, float fAngle)
	Sets a rotation matrix by using a selected axis and angle.
Vector3	GetXAxis () const
	Returns the x (left) axis.
Vector3	GetYAxis () const
	Returns the y (up) axis.
Vector3	GetZAxis () const
	Returns the z (forward) axis.
PLMATH_API void	ToAxis (Vector3 &vX, Vector3 &vY, Vector3 &vZ) const
	Returns the three axis of a rotation matrix (not normalized)
PLMATH_API void	FromAxis (const Vector3 &vX, const Vector3 &vY, const Vector3 &vZ)
	Sets a rotation matrix by using three given axis.
PLMATH_API Matrix3x4 &	LookAt (const Vector3 &vEye, const Vector3 &vAt, const Vector3 &vUp)
	Builds a look-at matrix.
PLMATH_API Matrix3x4 &	View (const Quaternion &qRotation, const Vector3 &vPosition)
	Builds a view matrix.
PLMATH_API Matrix3x4 &	FromQuatTrans (const Quaternion &qRotation, const Vector3 &vTranslation)
	Sets a matrix using a given quaternion and translation.
Matrix3x4 &	SetShearing (float fShearXY, float fShearXZ, float fShearYX, float fShearYZ, float fShearZX, float fShearZY)
	Sets a shearing matrix.
PLMATH_API Matrix3x4 &	SetReflection (const Plane &cPlane)
	Sets a matrix that reflects the coordinate system about a plane.
Public Attributes
union {
float   fM [12]
	One dimensional array representation.
struct {
float   xx
float   yx
float   zx
float   xy
float   yy
float   zy
float   xz
float   yz
float   zz
float   xw
float   yw
float   zw
}
	Direct element representation.
struct {
float   fM43 [4][3]
}
	Two dimensional array representation.
};
	Some direct matrix accesses.
Static Public Attributes
static PLMATH_API const Matrix3x4	Zero
static PLMATH_API const Matrix3x4	Identity

---

Detailed Description

3x4 matrix

Remarks:

Matrices are stored in column major order like OpenGL does. (right-handed matrix) So, it's possible to give OpenGL the matrix data without transposing it first.

Note:

• Some symbols within the comments: T = transposed, I = identity

---

Constructor & Destructor Documentation

PLMath::Matrix3x4::Matrix3x4

(

)

[inline]

Default constructor setting an identity matrix.

PLMath::Matrix3x4::Matrix3x4

(

const float

fS[]

)

[inline]

PLMATH_API PLMath::Matrix3x4::Matrix3x4

(

const Matrix3x3 &

mM

)

PLMath::Matrix3x4::Matrix3x4

(

const Matrix3x4 &

mM

)

[inline]

PLMATH_API PLMath::Matrix3x4::Matrix3x4

(

const Matrix4x4 &

mM

)

PLMath::Matrix3x4::Matrix3x4	(	float	fXX,
		float	fXY,
		float	fXZ,
		float	fXW,
		float	fYX,
		float	fYY,
		float	fYZ,
		float	fYW,
		float	fZX,
		float	fZY,
		float	fZZ,
		float	fZW
	)		[inline]

PLMath::Matrix3x4::~Matrix3x4

(

)

[inline]

---

Member Function Documentation

PLMATH_API bool PLMath::Matrix3x4::operator==

(

const Matrix3x4 &

mM

)

const

PLMATH_API bool PLMath::Matrix3x4::operator!=

(

const Matrix3x4 &

mM

)

const

PLMATH_API bool PLMath::Matrix3x4::CompareScale	(	const Matrix3x4 &	mM,
		float	fEpsilon = Math::Epsilon
	)		const

PLMATH_API bool PLMath::Matrix3x4::CompareTranslation	(	const Matrix3x4 &	mM,
		float	fEpsilon = Math::Epsilon
	)		const

PLMATH_API bool PLMath::Matrix3x4::CompareRotation	(	const Matrix3x4 &	mM,
		float	fEpsilon = Math::Epsilon
	)		const

Matrix3x4 & PLMath::Matrix3x4::operator=

(

const float

fS[]

)

[inline]

PLMATH_API Matrix3x4& PLMath::Matrix3x4::operator=

(

const Matrix3x3 &

mM

)

Matrix3x4 & PLMath::Matrix3x4::operator=

(

const Matrix3x4 &

mM

)

[inline]

PLMATH_API Matrix3x4& PLMath::Matrix3x4::operator=

(

const Matrix4x4 &

mM

)

Matrix3x4 PLMath::Matrix3x4::operator+

(

const Matrix3x4 &

mM

)

const [inline]

void PLMath::Matrix3x4::operator+=

(

const Matrix3x4 &

mM

)

[inline]

Matrix3x4 PLMath::Matrix3x4::operator-

(

)

const [inline]

Matrix3x4 PLMath::Matrix3x4::operator-

(

const Matrix3x4 &

mM

)

const [inline]

void PLMath::Matrix3x4::operator-=

(

const Matrix3x4 &

mM

)

[inline]

Matrix3x4 PLMath::Matrix3x4::operator*

(

float

fS

)

const [inline]

void PLMath::Matrix3x4::operator*=

(

float

fS

)

[inline]

Vector2 PLMath::Matrix3x4::operator*

(

const Vector2 &

vV

)

const [inline]

Vector3 PLMath::Matrix3x4::operator*

(

const Vector3 &

vV

)

const [inline]

Vector4 PLMath::Matrix3x4::operator*

(

const Vector4 &

vV

)

const [inline]

PLMATH_API Matrix3x4 PLMath::Matrix3x4::operator*

(

const Matrix3x4 &

mM

)

const

A 3x4*3x4 matrix multiplication is NOT defined, so we use the given 3x4 matrix with a fourth row (0, 0, 0, 1) which result in a 3x4*4x4 matrix multiplication which is allowed

PLMATH_API Matrix3x4 PLMath::Matrix3x4::operator*

(

const Matrix4x4 &

mM

)

const

void PLMath::Matrix3x4::operator*=

(

const Matrix3x4 &

mM

)

[inline]

See also:

- *(const Matrix3x4 &mM)

void PLMath::Matrix3x4::operator*=

(

const Matrix4x4 &

mM

)

[inline]

Matrix3x4 PLMath::Matrix3x4::operator/

(

float

fS

)

const [inline]

void PLMath::Matrix3x4::operator/=

(

float

fS

)

[inline]

float PLMath::Matrix3x4::operator[]

(

int

nIndex

)

const [inline]

float & PLMath::Matrix3x4::operator[]

(

int

nIndex

)

[inline]

float PLMath::Matrix3x4::operator()	(	PLCore::uint32	nRow = 0,
		PLCore::uint32	nColumn = 0
	)		const [inline]

float & PLMath::Matrix3x4::operator()	(	PLCore::uint32	nRow = 0,
		PLCore::uint32	nColumn = 0
	)		[inline]

PLMath::Matrix3x4::operator float *

(

)

[inline]

PLMath::Matrix3x4::operator const float *

(

)

const [inline]

bool PLMath::Matrix3x4::IsZero

(

)

const [inline]

Returns whether or not this matrix is the zero matrix using an epsilon environment.

Returns:

'true' if this matrix is the zero matrix, else 'false'

bool PLMath::Matrix3x4::IsTrueZero

(

)

const [inline]

Returns whether or not this matrix is truly the zero matrix.

Returns whether or not this matrix is truely the zero matrix.

Remarks:

All components MUST be exactly 0. Floating point inaccuracy is not taken into account.

Returns:

'true' if this matrix is truly the zero matrix, else 'false'

void PLMath::Matrix3x4::SetZero

(

)

[inline]

Sets a zero matrix.

Remarks:

    | 0 0 0 0 |
    | 0 0 0 0 |
    | 0 0 0 0 |

bool PLMath::Matrix3x4::IsIdentity

(

)

const [inline]

Returns whether or not this matrix is the identity matrix using an epsilon environment.

Returns:

'true' if this matrix is the identity matrix, else 'false'

bool PLMath::Matrix3x4::IsTrueIdentity

(

)

const [inline]

Returns whether or not this matrix is truly the identity matrix.

Returns whether or not this matrix is truely the identity matrix.

Remarks:

All components MUST be exactly either 0 or 1. Floating point inaccuracy is not taken into account.

Returns:

'true' if this matrix is truly the identity matrix, else 'false'

void PLMath::Matrix3x4::SetIdentity

(

)

[inline]

Sets an identity matrix.

Remarks:

    | 1 0 0 0 |
    | 0 1 0 0 |
    | 0 0 1 0 |

PLMATH_API void PLMath::Matrix3x4::Set	(	float	fXX,
		float	fXY,
		float	fXZ,
		float	fXW,
		float	fYX,
		float	fYY,
		float	fYZ,
		float	fYW,
		float	fZX,
		float	fZY,
		float	fZZ,
		float	fZW
	)

Sets the elements of the matrix.

Vector4 PLMath::Matrix3x4::GetRow

(

PLCore::uint8

nRow

)

const [inline]

Returns a requested row.

Parameters:

[in]

nRow

Index of the row to return (0-2)

Returns:

The requested row (null vector on error)

Remarks:

    | x y z w | <- Row 0
    | 0 0 0 0 |
    | 0 0 0 0 |

void PLMath::Matrix3x4::SetRow	(	PLCore::uint8	nRow,
		const Vector4 &	vRow
	)		[inline]

Sets a row.

Parameters:

[in]	nRow	Index of the row to set (0-2)
[in]	vRow	Row vector

See also:

• GetRow()

Vector3 PLMath::Matrix3x4::GetColumn

(

PLCore::uint8

nColumn

)

const [inline]

Returns a requested column.

Parameters:

[in]

nColumn

Index of the column to return (0-3)

Returns:

The requested column (null vector on error)

Remarks:

    | x 0 0 0 |
    | y 0 0 0 |
    | z 0 0 0 |
      ^
      |
      Column 0

void PLMath::Matrix3x4::SetColumn	(	PLCore::uint8	nColumn,
		const Vector3 &	vColumn
	)		[inline]

Sets a column.

Parameters:

[in]	nColumn	Index of the column to set (0-3)
[in]	vColumn	Column vector

See also:

• GetColumn()

bool PLMath::Matrix3x4::IsSymmetric

(

)

const [inline]

Returns true if the matrix is symmetric.

Returns true if this matrix is symmetric.

Returns:

'true' if the matrix is symmetric, else 'false'

Remarks:

A matrix is symmetric if it is equal to it's transposed matrix.
A = A^T -> a(i, j) = a(j, i)

bool PLMath::Matrix3x4::IsOrthogonal

(

)

const [inline]

Returns true if this matrix is orthogonal.

Returns:

'true' if the matrix is orthogonal, else 'false'

Remarks:

A matrix is orthogonal if it's transposed matrix is equal to it's inversed matrix.
A^T = A^-1 or A*A^T = A^T*A = I

Note:

• An orthogonal matrix is always nonsingular (invertible) and it's inverse is equal to it's transposed
• The transpose and inverse of the matrix is orthogonal, too
• Products of orthogonal matrices are orthogonal, too
• The determinant of a orthogonal matrix is +/- 1
• The row and column vectors of an orthogonal matrix form an orthonormal basis, that is, these vectors are unit-length and they are mutually perpendicular

bool PLMath::Matrix3x4::IsRotationMatrix

(

)

const [inline]

Returns true if this matrix is a rotation matrix.

Returns:

'true' if this matrix is a rotation matrix, else 'false'

Remarks:

A rotation matrix is orthogonal and it's determinant is 1 to rule out reflections.

See also:

• IsOrthogonal()

bool PLMath::Matrix3x4::IsRotationTranslationMatrix

(

)

const [inline]

Returns true if this matrix is a rotation and translation matrix.

Returns:

'true' if this matrix is a rotation and translation matrix, else 'false'

Remarks:

A rotation and translation matrix looks like this:

      | x x x x |
      | x x x x |
      | x x x x |

Were 'x' means this field is used and as you see the last row must be empty.

See also:

• IsRotationMatrix()

float PLMath::Matrix3x4::GetTrace

(

)

const [inline]

Returns the trace of the matrix.

Returns:

The trace of the matrix

Remarks:

The trace of the matrix is the sum of the main diagonal elements:
xx+yy+zz

float PLMath::Matrix3x4::GetDeterminant

(

)

const [inline]

Returns the determinant of the matrix.

Returns:

Determinant of the matrix

Remarks:

The determinant is calculated using the Sarrus diagram:

      | xx   xy   xz  |  xx   xy |
      |     \   /\   /\     /    |
      | yx   yy   yz  |  yx   yy | =  xx*yy*zz + xy*yz*zx + xz*yx*zy -
      |    /    /\   /\      \   |   (zx*yy*xz + zy*yz*xx + zz*yx*xy)
      | zx   zy   zz  |  zx   zy |

Note:

• If the determinant is non-zero, then an inverse matrix exists
• If the determinant is 0, the matrix is called singular, else nonsingular (invertible) matrix
• If the determinant is 1, the inverse matrix is equal to the transpose of the matrix

void PLMath::Matrix3x4::Transpose

(

)

[inline]

Transpose this matrix.

Remarks:

The transpose of matrix is the matrix generated when every element in the matrix is swapped with the opposite relative to the major diagonal This can be expressed as the mathematical operation:

      M'   = M
        ij    ji

      | xx xy xz xw |                    | xx yx zx xw |
      | yx yy yz yw |  the transpose is  | xy yy zy yw |
      | zx zy zz zw |                    | xz yz zz zw |

Note:

• If the matrix is a rotation matrix (= isotropic matrix = determinant is 1), then the transpose is guaranteed to be the inverse of the matrix
• Only the upper left 3x3 part is manipulated

Matrix3x4 PLMath::Matrix3x4::GetTransposed

(

)

const [inline]

Returns the transposed matrix.

Returns:

Transposed matrix

See also:

• Transpose()

PLMATH_API bool PLMath::Matrix3x4::Invert

(

)

Inverts the matrix.

Returns:

'true' if all went fine, else 'false' (maybe the determinant is null?)

Remarks:

P = [R T] -> inv(P) = [R' -R'*T] (R = rotation, R' = transposed rotation, T = translation vector)

Note:

• If the determinant is 1, the inversed matrix is equal to the transposed one

PLMATH_API Matrix3x4 PLMath::Matrix3x4::GetInverted

(

)

const

Returns the inverse of the matrix.

Returns:

Inverse of the matrix, if the determinant is null, an identity matrix is returned

See also:

• Invert()

PLMATH_API Vector3 PLMath::Matrix3x4::RotateVector	(	float	fX,
		float	fY,
		float	fZ,
		bool	bUniformScale = false
	)		const

Rotates a vector.

Parameters:

[in]	fX	X component of the vector to rotate
[in]	fY	Y component of the vector to rotate
[in]	fZ	Z component of the vector to rotate
[in]	bUniformScale	Is this a uniform scale matrix? (all axis are scaled equally) If you know EXACTLY it's one, set this to 'true' to gain some more speed, else DON'T set to 'true'!

Returns:

The rotated vector

Remarks:

This function is similar to a matrix * vector operation - except that the translation of the matrix is ignored and this function can deal with none uniform scale. So, this function can for instance be used to rotate a direction vector. (matrix * direction vector)

Note:

• You can't assume that the resulting vector is normalized
• Use this function to rotate for example a normal vector

PLMATH_API Vector3 PLMath::Matrix3x4::RotateVector	(	const Vector3 &	vV,
		bool	bUniformScale = false
	)		const

Rotates a vector.

Parameters:

[in]	vV	Vector to rotate
[in]	bUniformScale	Is this a uniform scale matrix? (all axis are scaled equally) If you know EXACTLY it's one, set this to 'true' to gain some more speed, else DON'T set to 'true'!

Returns:

The rotated vector

See also:

• RotateVector(float, float, float) above

void PLMath::Matrix3x4::SetScaleMatrix	(	float	fX,
		float	fY,
		float	fZ
	)		[inline]

Sets a scale matrix.

Parameters:

[in]	fX	X scale
[in]	fY	Y scale
[in]	fZ	Z scale

Remarks:

    | x 0 0 0 |
    | 0 y 0 0 |
    | 0 0 z 0 |

void PLMath::Matrix3x4::SetScaleMatrix

(

const Vector3 &

vV

)

[inline]

PLMATH_API void PLMath::Matrix3x4::GetScale	(	float &	fX,
		float &	fY,
		float &	fZ
	)		const

Extracts the scale vector from the matrix as good as possible.

Parameters:

[out]	fX	Receives the x scale
[out]	fY	Receives the y scale
[out]	fZ	Receives the z scale

Note:

• This function will not work correctly if one or two components are negative while another is/are not (we can't figure out WHICH axis are negative!)

Vector3 PLMath::Matrix3x4::GetScale

(

)

const [inline]

void PLMath::Matrix3x4::GetScale

(

float

fV[]

)

const [inline]

void PLMath::Matrix3x4::SetTranslationMatrix	(	float	fX,
		float	fY,
		float	fZ
	)		[inline]

Sets a translation matrix.

Parameters:

[in]	fX	X translation
[in]	fY	Y translation
[in]	fZ	Z translation

Remarks:

    | 1 0 0 x |
    | 0 1 0 y |
    | 0 0 1 z |

void PLMath::Matrix3x4::SetTranslationMatrix

(

const Vector3 &

vV

)

[inline]

void PLMath::Matrix3x4::GetTranslation	(	float &	fX,
		float &	fY,
		float &	fZ
	)		const [inline]

Vector3 PLMath::Matrix3x4::GetTranslation

(

)

const [inline]

void PLMath::Matrix3x4::GetTranslation

(

float

fV[]

)

const [inline]

void PLMath::Matrix3x4::SetTranslation	(	float	fX = 0.0f,
		float	fY = 0.0f,
		float	fZ = 0.0f
	)		[inline]

void PLMath::Matrix3x4::SetTranslation

(

const Vector3 &

vV

)

[inline]

void PLMath::Matrix3x4::SetTranslation

(

const float

fV[]

)

[inline]

PLMATH_API void PLMath::Matrix3x4::FromEulerAngleX

(

float

fAngleX

)

Sets an x axis rotation matrix by using one given Euler angle.

Parameters:

[in]

fAngleX

Rotation angle around the x axis (in radian, between [0, Math::Pi2])

Remarks:

         |    1       0       0    0 |
    RX = |    0     cos(a) -sin(a) 0 |
         |    0     sin(a)  cos(a) 0 |

where a > 0 indicates a counterclockwise rotation in the yz-plane (if you look along -x)

PLMATH_API void PLMath::Matrix3x4::FromEulerAngleY

(

float

fAngleY

)

Sets an y axis rotation matrix by using one given Euler angle.

Parameters:

[in]

fAngleY

Rotation angle around the y axis (in radian, between [0, Math::Pi2])

Remarks:

         |  cos(a)    0     sin(a) 0 |
    RY = |    0       1       0    0 |
         | -sin(a)    0     cos(a) 0 |

where a > 0 indicates a counterclockwise rotation in the zx-plane (if you look along -y)

PLMATH_API void PLMath::Matrix3x4::FromEulerAngleZ

(

float

fAngleZ

)

Sets an z axis rotation matrix by using one given Euler angle.

Parameters:

[in]

fAngleZ

Rotation angle around the z axis (in radian, between [0, Math::Pi2])

Remarks:

         |  cos(a) -sin(a)    0    0 |
    RZ = |  sin(a)  cos(a)    0    0 |
         |    0       0       1    0 |

where a > 0 indicates a counterclockwise rotation in the xy-plane (if you look along -z)

PLMATH_API void PLMath::Matrix3x4::ToAxisAngle	(	float &	fX,
		float &	fY,
		float &	fZ,
		float &	fAngle
	)		const

Returns a rotation matrix as a selected axis and angle.

Parameters:

[out]	fX	Will receive the x component of the selected axis
[out]	fY	Will receive the y component of the selected axis
[out]	fZ	Will receive the z component of the selected axis
[out]	fAngle	Will receive the rotation angle around the selected axis (in radian, between [0, Math::Pi])

PLMATH_API void PLMath::Matrix3x4::FromAxisAngle	(	float	fX,
		float	fY,
		float	fZ,
		float	fAngle
	)

Sets a rotation matrix by using a selected axis and angle.

Parameters:

[in]	fX	X component of the selected axis
[in]	fY	Y component of the selected axis
[in]	fZ	Z component of the selected axis
[in]	fAngle	Rotation angle around the selected axis (in radian, between [0, Math::Pi])

Note:

• The given selected axis must be normalized!

Vector3 PLMath::Matrix3x4::GetXAxis

(

)

const [inline]

Returns the x (left) axis.

Returns:

The x (left) axis

Remarks:

    | x 0 0 0 |
    | y 0 0 0 |
    | z 0 0 0 |

Note:

• It's possible that the axis vector is not normalized because for instance the matrix was scaled

Vector3 PLMath::Matrix3x4::GetYAxis

(

)

const [inline]

Returns the y (up) axis.

Returns:

The y (up) axis

Remarks:

    | 0 x 0 0 |
    | 0 y 0 0 |
    | 0 z 0 0 |

See also:

• GetXAxis()

Vector3 PLMath::Matrix3x4::GetZAxis

(

)

const [inline]

Returns the z (forward) axis.

Returns:

The z (forward) axis

Remarks:

    | 0 0 x 0 |
    | 0 0 y 0 |
    | 0 0 z 0 |

See also:

• GetXAxis()

PLMATH_API void PLMath::Matrix3x4::ToAxis	(	Vector3 &	vX,
		Vector3 &	vY,
		Vector3 &	vZ
	)		const

Returns the three axis of a rotation matrix (not normalized)

Parameters:

[out]	vX	Will receive the x axis
[out]	vY	Will receive the y axis
[out]	vZ	Will receive the z axis

Remarks:

    | vX.x vY.x vZ.x 0 |
    | vX.y vY.y vZ.y 0 |
    | vX.z vY.z vZ.z 0 |

PLMATH_API void PLMath::Matrix3x4::FromAxis	(	const Vector3 &	vX,
		const Vector3 &	vY,
		const Vector3 &	vZ
	)

Sets a rotation matrix by using three given axis.

Parameters:

[in]	vX	X axis
[in]	vY	Y axis
[in]	vZ	Z axis

See also:

• ToAxis()

PLMATH_API Matrix3x4& PLMath::Matrix3x4::LookAt	(	const Vector3 &	vEye,
		const Vector3 &	vAt,
		const Vector3 &	vUp
	)

Builds a look-at matrix.

Parameters:

[in]	vEye	Eye position
[in]	vAt	Camera look-at target
[in]	vUp	Current world's up, usually [0, 1, 0]

Returns:

This instance

PLMATH_API Matrix3x4& PLMath::Matrix3x4::View	(	const Quaternion &	qRotation,
		const Vector3 &	vPosition
	)

Builds a view matrix.

Parameters:

[in]	qRotation	Rotation quaternion
[in]	vPosition	Position vector

Returns:

This instance

Remarks:

    | RotT.xx RotT.xy RotT.xz T.x |
    | RotT.yx RotT.yy RotT.yz T.y |
    | RotT.zx RotT.zy RotT.zz T.z |

RotT = Transposed(Rot) T = -(Transposed(Rot) * Pos)

PLMATH_API Matrix3x4& PLMath::Matrix3x4::FromQuatTrans	(	const Quaternion &	qRotation,
		const Vector3 &	vTranslation
	)

Sets a matrix using a given quaternion and translation.

Parameters:

[in]	qRotation	Rotation quaternion
[in]	vTranslation	Translation vector

Returns:

This instance

Remarks:

First this function is using Quaternion::ToRotationMatrix() to create a rotation matrix. Then the translation components are set. (Matrix3x4::SetTranslation())

Matrix3x4 & PLMath::Matrix3x4::SetShearing	(	float	fShearXY,
		float	fShearXZ,
		float	fShearYX,
		float	fShearYZ,
		float	fShearZX,
		float	fShearZY
	)		[inline]

Sets a shearing matrix.

Parameters:

[in]	fShearXY	Shear X by Y
[in]	fShearXZ	Shear X by Z
[in]	fShearYX	Shear Y by X
[in]	fShearYZ	Shear Y by Z
[in]	fShearZX	Shear Z by X
[in]	fShearZY	Shear Z by Y

Returns:

This instance

Remarks:

A shearing matrix can be used to for instance make a 3D model appear to slant sideways. Here's a table showing how a combined shearing matrix looks like:

    | 1        fShearYX  fShearZX  0 |
    | fShearXY 1         fShearZY  0 |
    | fShearXZ fShearYZ  1         0 |

If you only want to shear one axis it's recommended to construct the matrix by yourself.

PLMATH_API Matrix3x4& PLMath::Matrix3x4::SetReflection

(

const Plane &

cPlane

)

Sets a matrix that reflects the coordinate system about a plane.

Parameters:

[in]

cPlane

Reflection plane (must be normalized!)

Returns:

This instance

Remarks:

    | -2*cPlane.a*cPlane.a+1 -2*cPlane.a*cPlane.b   -2*cPlane.a*cPlane.c   -2*cPlane.a*cPlane.d |
    | -2*cPlane.b*cPlane.a   -2*cPlane.b*cPlane.b+1 -2*cPlane.b*cPlane.c   -2*cPlane.b*cPlane.d |
    | -2*cPlane.c*cPlane.a   -2*cPlane.c*cPlane.b   -2*cPlane.c*cPlane.c+1 -2*cPlane.c*cPlane.d |

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Member Data Documentation

PLMATH_API const Matrix3x4 PLMath::Matrix3x4::Zero [static]

Zero matrix

PLMATH_API const Matrix3x4 PLMath::Matrix3x4::Identity [static]

Identity matrix

float PLMath::Matrix3x4::fM[12]

One dimensional array representation.

Remarks:

The entry of the matrix in row r (0 <= r <= 2) and column c (0 <= c <= 3) is stored at index i = r+3*c (0 <= i <= 11).
Indices:

      | 0  3  6  9  |
      | 1  4  7  10 |
      | 2  5  8  11 |

float PLMath::Matrix3x4::xx

float PLMath::Matrix3x4::yx

float PLMath::Matrix3x4::zx

float PLMath::Matrix3x4::xy

float PLMath::Matrix3x4::yy

float PLMath::Matrix3x4::zy

float PLMath::Matrix3x4::xz

float PLMath::Matrix3x4::yz

float PLMath::Matrix3x4::zz

float PLMath::Matrix3x4::xw

float PLMath::Matrix3x4::yw

float PLMath::Matrix3x4::zw

float PLMath::Matrix3x4::fM43[4][3]

union { ... }

Some direct matrix accesses.

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

• Matrix3x4.h
• Matrix3x4.inl