D3DXMatrixAffineTransformation function (D3dx9math.h)

Article
04/28/2022

Note

The D3DX utility library is deprecated. We recommend that you use DirectXMath instead.

Builds a 3D affine transformation matrix. NULL arguments are treated as identity transformations.

Syntax

D3DXMATRIX* D3DXMatrixAffineTransformation(
  _Inout_       D3DXMATRIX     *pOut,
  _In_          FLOAT          Scaling,
  _In_    const D3DXVECTOR3    *pRotationCenter,
  _In_    const D3DXQUATERNION *pRotation,
  _In_    const D3DXVECTOR3    *pTranslation
);

Parameters

pOut [in, out]

Type: D3DXMATRIX*

Pointer to the D3DXMATRIX structure that is the result of the operation.

Scaling [in]

Type: FLOAT

Scaling factor.

pRotationCenter [in]

Type: const D3DXVECTOR3*

Pointer to a D3DXVECTOR3 structure, a point identifying the center of rotation. If this argument is NULL, an identity M_rc matrix is applied to the formula in Remarks.

pRotation [in]

Type: const D3DXQUATERNION*

Pointer to a D3DXQUATERNION structure that specifies the rotation. If this argument is NULL, an identity M_r matrix is applied to the formula in Remarks.

pTranslation [in]

Type: const D3DXVECTOR3*

Pointer to a D3DXVECTOR3 structure representing 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 is an affine transformation matrix.

Remarks

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

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

where:

M_out = output matrix (pOut)

Mₛ = scaling matrix (Scaling)

M_rc = center of rotation matrix (pRotationCenter)

M_r = rotation matrix (pRotation)

Mₜ = translation matrix (pTranslation)

The return value for this function is the same value returned in the pOut parameter. In this way, the D3DXMatrixAffineTransformation function can be used as a parameter for another function.

For 2D affine transformations, use D3DXMatrixAffineTransformation2D.

Requirements

Requirement	Value
Header	D3dx9math.h
Library	D3dx9.lib