Microsoft DirectX 9.0

Standard Audiopaths

If your application does not play exclusively on audiopaths created from audiopath configuration objects, you must create one or more standard audiopaths.

Standard audiopaths are identified by the values passed in the dwType parameter of IDirectMusicPerformance8::CreateStandardAudioPath or in the dwDefaultPathType parameter of IDirectMusicPerformance8::InitAudio.

The audiopaths defined by DirectMusic manage the flow of synthesizer output through combinations of standard buffers, some of which have effect DMOs attached to them. The following table shows the standard audiopaths and which standard buffers they contain. Shared buffers can be used by more than one audiopath.

Audiopath type Standard buffers Buffer shared?
DMUS_APATH_DYNAMIC_3D 3-D Dry No
DMUS_APATH_DYNAMIC_MONO Mono No
DMUS_APATH_DYNAMIC_STEREO Stereo No
DMUS_APATH_SHARED_STEREOPLUSREVERB Music
Reverb
Yes
Yes

Characteristics of the standard buffers are shown in the following table, where the Capabilities column lists values returned in the dwFlags member of the DSBCAPS structure passed to IDirectSoundBuffer8::GetCaps. The last column shows interfaces that can be obtained from the buffer object. In addition, applications can add effects to buffers by using IDirectSoundBuffer8::SetFX, making other interfaces available. For more information on obtaining interfaces, see Retrieving Objects from an Audiopath.

Standard buffer Description Capabilities Interfaces
3-D Dry Mono 3-D buffer DSBCAPS_CTRL3D
DSBCAPS_CTRLFREQUENCY
DSBCAPS_CTRLFX
DSBCAPS_CTRLVOLUME
DSBCAPS_GLOBALFOCUS
DSBCAPS_MUTE3DATMAXDISTANCE
IDirectSound3DBuffer8
IDirectSoundBuffer8
IDirectSound3DBuffer8
Mono Mono buffer with no effects DSBCAPS_CTRLFREQUENCY
DSBCAPS_CTRLFX
DSBCAPS_CTRLPAN
DSBCAPS_CTRLVOLUME
DSBCAPS_GLOBALFOCUS
IDirectSoundBuffer8
Music Stereo buffer used with Reverb DSBCAPS_CTRLFX
DSBCAPS_CTRLPAN
DSBCAPS_CTRLVOLUME
DSBCAPS_GLOBALFOCUS
IDirectSoundBuffer8
Reverb Stereo buffer with music reverberation effect DSBCAPS_CTRLFX
DSBCAPS_CTRLPAN
DSBCAPS_CTRLVOLUME
DSBCAPS_GLOBALFOCUS
IDirectSoundFXWavesReverb8
IDirectSoundBuffer8
Stereo Stereo buffer with no effects DSBCAPS_CTRLFREQUENCY, DSBCAPS_CTRLFX,
DSBCAPS_CTRLPAN
DSBCAPS_CTRLVOLUME
DSBCAPS_GLOBALFOCUS
IDirectSoundBuffer8

More information about the standard audiopaths is available in the following topics: