|Microsoft DirectX 9.0|
The Compose method recomposes the track based on data from a segment. DirectMusic implements this method on the signpost track to compose a chord track.
HRESULT Compose( IUnknown* pContext, DWORD dwTrackGroup, IDirectMusicTrack** ppResultTrack );
IUnknown interface pointer of the object to use in the composition. This is usually the segment that owns this track.
DWORD value that specifies group bits for the track. For more information on group bits, see Identifying the Track.
Address of a variable that receives the IDirectMusicTrack interface of the composed track. Use QueryInterface to obtain IDirectMusicTrack8.
If the method succeeds, the return value is S_OK.
If it fails, the method can return one of the error values shown in the following table.
Header: Declared in dmplugin.h.