MKNoteFilter Class A MKNoteFilter (subclass of
MKInstrument) is an abstract class that
processes MKNotes in some manner.
MKNoteFilter inherits the
MKNote-receiving behavior of
MKInstrument. It also supports the
MKNote-sending behavior of
MKPerformer.
Like any other MKInstrument,
MKNoteFilters implement realizeNote:fromNoteReceiver: to process
MKNotes it receives.
Example: MidiEcho.
Rules:
1. Copy MKNote on write.
(Or return MKNote to original condition)
2. Copy MKNote on store.
Ensemble is an Application
based on MKNoteFilters.