IDirect3DDevice9::MultiplyTransform method (d3d9.h)
Multiplies a device's world, view, or projection matrices by a specified matrix.
Syntax
HRESULT MultiplyTransform(
[in] D3DTRANSFORMSTATETYPE unnamedParam1,
[in] const D3DMATRIX *unnamedParam2
);
Parameters
[in] unnamedParam1
Type: D3DTRANSFORMSTATETYPE
Member of the D3DTRANSFORMSTATETYPE enumerated type, or the D3DTS_WORLDMATRIX macro that identifies which device matrix is to be modified. The most common setting, D3DTS_WORLDMATRIX(0), modifies the world matrix, but you can specify that the method modify the view or projection matrices, if needed.
[in] unnamedParam2
Type: const D3DMATRIX*
Pointer to a D3DMATRIX structure that modifies the current transformation.
Return value
Type: HRESULT
If the method succeeds, the return value is D3D_OK. D3DERR_INVALIDCALL if one of the arguments is invalid.
Remarks
The multiplication order is pMatrix times State.
An application might use the IDirect3DDevice9::MultiplyTransform method to work with hierarchies of transformations. For example, the geometry and transformations describing an arm might be arranged in the following hierarchy.
shoulder_transformation
upper_arm geometry
elbow transformation
lower_arm geometry
wrist transformation
hand geometry
An application might use the following series of calls to render this hierarchy. Not all the parameters are shown in this pseudocode.
IDirect3DDevice9::SetTransform(D3DTS_WORLDMATRIX(0),
shoulder_transform)
IDirect3DDevice9::DrawPrimitive(upper_arm)
IDirect3DDevice9::MultiplyTransform(D3DTS_WORLDMATRIX(0),
elbow_transform)
IDirect3DDevice9::DrawPrimitive(lower_arm)
IDirect3DDevice9::MultiplyTransform(D3DTS_WORLDMATRIX(0),
wrist_transform)
IDirect3DDevice9::DrawPrimitive(hand)
Requirements
| Requirement | Value |
|---|---|
| Target Platform | Windows |
| Header | d3d9.h (include D3D9.h) |
| Library | D3D9.lib |