Q: Sending MIDI events seems to have no effect. Have I set my MIDI destinations correctly? A music player is associated with a music sequence in a one-to-one relationship. A music sequence is designed to hold various music tracks, which are intended to be logical groupings of events. The MusicPlayerSetSequence method will associate a sequence and its tracks with a music player. A MusicSequence may have an associated AUGraph object, which represents a set of AudioUnits and the connections between them. Thus, each MusicTrack of the MusicSequence may address its events to a specific AudioUnit within the AUGraph . MusicPlayerSetSequence automatically will associate a MusicSequence to a MusicPlayer in the sequences' default configuration; this includes setting the sequences' tracks to their default destinations.
The methods MusicSequenceSetMIDIEndpoint or MusicSequenceSetAUGraph can assign an entire sequence to a specific endpoint or an AUGraph . However, if a client would like to have custom connections of the tracks of a sequence to particular AudioUnits within an AUGraph , a call to MusicTrackSetDestNode must be made after MusicPlayerSetSequence is used. This is the same when connecting individual tracks to MIDIEndpoints; MusicTrackSetDestMIDIEndpoint must be called only after MusicPlayerSetSequence .
For more infromation on the MusicPlayer API. Please see Audio and MIDI on Mac OS X -May 2001
[Jan 15, 2004]
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