D3DXMatrixTransformation2D function (D3dx9math.h)

Builds a 2D transformation matrix that represents transformations in the xy plane. NULL arguments are treated as identity transformations.

Syntax

D3DXMATRIX* D3DXMatrixTransformation2D(
  _Inout_       D3DXMATRIX  *pOut,
  _In_    const D3DXVECTOR2 *pScalingCenter,
  _In_          FLOAT       pScalingRotation,
  _In_    const D3DXVECTOR2 *pScaling,
  _In_    const D3DXVECTOR2 *pRotationCenter,
  _In_          FLOAT       Rotation,
  _In_    const D3DXVECTOR2 *pTranslation
);

Parameters

pOut [in, out]

Type: D3DXMATRIX*

Pointer to the D3DXMATRIX structure that contains the result of the transformations.

pScalingCenter [in]

Type: const D3DXVECTOR2*

Pointer to a D3DXVECTOR2 structure, a point identifying the scaling center. If this argument is NULL, an identity M_sc matrix is applied to the formula in Remarks.

pScalingRotation [in]

Type: FLOAT

The scaling rotation factor.

pScaling [in]

Type: const D3DXVECTOR2*

Pointer to a D3DXVECTOR2 structure, a point identifying the scale. If this argument is NULL, an identity Mₛ matrix is applied to the formula in Remarks.

pRotationCenter [in]

Type: const D3DXVECTOR2*

Pointer to a D3DXVECTOR2 structure, a point identifying the rotation center. If this argument is NULL, an identity M_rc matrix is applied to the formula in Remarks.

Rotation [in]

Type: FLOAT

The angle of rotation in radians.

pTranslation [in]

Type: const D3DXVECTOR2*

Pointer to a D3DXVECTOR2 structure, identifying the translation. If this argument is NULL, an identity Mₜ matrix is applied to the formula in Remarks.

Return value

Type: D3DXMATRIX*

Pointer to a D3DXMATRIX structure that contains the transformation matrix.

Remarks

This function calculates the transformation matrix with the following formula, with matrix concatenation evaluated in left-to-right order:

M_out = (M_sc)⁻¹* (M_sr)⁻¹* Mₛ * M_sr * M_sc * (M_rc)⁻¹* M_r * M_rc * Mₜ

where:

M_out = output matrix (pOut)

M_sc = scaling center matrix (pScalingCenter)

M_sr = scaling rotation matrix (pScalingRotation)

Mₛ = scaling matrix (pScaling)

M_rc = center of rotation matrix (pRotationCenter)

M_r = rotation matrix (Rotation)

Mₜ = translation matrix (pTranslation)

The return value for this function is the same value returned in the pOut parameter. In this way, the D3DXMatrixTransformation2D function can be used as a parameter for another function.

For 3D transformations, use D3DXMatrixTransformation.

Requirements

See also

Math Functions

D3DXMatrixAffineTransformation2D

Transforms (Direct3D 9)