IDirect3DDevice2::MultiplyTransform

IDirect3DDevice2::MultiplyTransform

The IDirect3DDevice2::MultiplyTransform method modifies the current world matrix by combining it with a specified matrix. The multiplication order is lpD3DMatrix times dtstTransformStateType.

HRESULT MultiplyTransform(

D3DTRANSFORMSTATETYPE dtstTransformStateType,

LPD3DMATRIX lpD3DMatrix

);

Parameters

dtstTransformStateType

One of the members of the D3DTRANSFORMSTATETYPE enumerated type. Only the D3DTRANSFORMSTATE_WORLD setting is likely to be useful. The matrix referred to by this parameter is modified by this method.

lpD3DMatrix

Address of a D3DMATRIX structure that modifies the current transformation.

Return Values

If the method succeeds, the return value is DD_OK.

If the method fails, the return value is an error. The method returns DDERR_INVALIDPARAMS if one of the arguments is invalid.

Remarks

An application might use the IDirect3DDevice2::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 of the parameters are shown in this pseudocode.)

IDirect3DDevice2::SetTransform(D3DTRANSFORMSTATE_WORLD,

shoulder_transform)

IDirect3DDevice2::DrawPrimitive(upper_arm)

IDirect3DDevice2::MultiplyTransform(D3DTRANSFORMSTATE_WORLD,

elbow_transform)

IDirect3DDevice2::DrawPrimitive(lower_arm)

IDirect3DDevice2::MultiplyTransform(D3DTRANSFORMSTATE_WORLD,

wrist_transform)

IDirect3DDevice2::DrawPrimitive(hand)

This method was introduced with the IDirect3DDevice2 interface.

QuickInfo

  Windows NT: Use version 5.0 or later.
  Windows: Use Windows 95 or later. Available as a redistributable for Windows 95.
  Windows CE: Unsupported.
  Header: Declared in d3d.h.
  Import Library: Use ddraw.lib.