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Wired Movies and Sprites

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Constant descriptions

kActionMusicPlayNote

none Param1: [long sampleDescIndex] Param2: [long partNumber] Param3: [long delay] Param4: [long pitch] Param5: [long velocity] Param6: [long duration]

This causes the target music track to play a note. Since the current selection of instruments for a music track is determined by its sample description, you use the sampleDescIndex parameter to select which sample description to use. The partNumber parameter specifies which part to use within the sample descriptions list. The default is 1.

If you want the note to be delayed, you may pass a positive value for the delay parameter, which is interpreted in the time scale of the music track. Pass 0 for no delay. The pitch parameter selects which note to play; for example, Middle C is 60, Middle B is 59. The velocity specifies the volume that the note is played at. The duration specifies the length of time that the note is played for and is interpreted in the time scale of the music track.

When using a music track to play notes, you should set the kMusicFlagDontSlaveToMovie flag in the MusicDescription's musicFlags field. The music track used for playing notes should not contain note information. If you wish to layer notes on top of other music, you should use two separate music tracks.

By setting duration to kNoteEventDurationMax , the note will continue playing until you send another kActionMusicPlayNote for the same pitch with a velocity of 0. This allows you to hold a note for an interactive period of time. For example, on mouseDown , you play a note, and on mouseUp to turn it off.

kActionMusicSetController

none Param1: [long sampleDescIndex] Param2: [long partNumber] Param3: [long delay] Param4: [long controller] Param5: [long value]

Sets a controller value for a part in the target music track. Since the current selection of instruments for a music track is determined by its sample description, you use the sampleDescIndex parameter to select which sample description to use. The partNumber parameter specifies which part to use within the sample descriptions list.

If you want the controller change to be delayed, you may pass a positive value for the delay parameter, which is interpreted in the time scale of the music track. Pass 0 for no delay. Controller values control things, such as pitch bend and reverb. For more information about available controllers, see QuickTime Music Architecture.