D3DXMatrixAffineTransformation2D
Microsoft DirectX 9.0 SDK Update (October 2004)

D3DXMatrixAffineTransformation2D Function


Builds a 2-D affine transformation matrix in the x-y plane. NULL arguments are treated as identity transformations.

Syntax

D3DXMATRIX *WINAPI D3DXMatrixAffineTransformation2D(      

    D3DXMATRIX *pOut,     FLOAT Scaling,     CONST D3DXVECTOR2 *pRotationCenter,     FLOAT Rotation,     CONST D3DXVECTOR2 *pTranslation );

Parameters

pOut
[in, out] Pointer to the D3DXMATRIX structure that is the result of the operation.
Scaling
[in] Scaling factor.
pRotationCenter
[in] Pointer to a D3DXVECTOR2 structure, a point identifying the center of rotation. If this argument is NULL, an identity Mrc matrix is applied to the formula in Remarks.
Rotation
[in] The angle of rotation.
pTranslation
[in] Pointer to a D3DXVECTOR2 structure, representing the translation. If this argument is NULL, an identity Mt matrix is applied to the formula in Remarks.

Return Value

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:

    Mout = Ms * (Mrc)-1 * Mr * Mrc * Mt

where:

    Mout = output matrix (pOut)

    Ms = scaling matrix (Scaling)

    Mrc = center of rotation matrix (pRotationCenter)

    Mr = 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 D3DXMatrixAffineTransformation2D function can be used as a parameter for another function.

For 3-D affine transformations, use D3DXMatrixAffineTransformation.

Function Information

Headerd3dx9math.h
Import libraryd3dx9.lib
Minimum operating systems Windows 98

See Also

D3DXMatrixTransformation2D, Matrix Transforms


© 2004 Microsoft Corporation. All rights reserved.
Feedback? Please provide us with your comments on this topic.
For more help, visit the DirectX Developer Center.