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dejf_mk
02-14-2011, 11:34 AM
Hi Cam et al,
I would like to ask for some help understanding the Voice / Index note
parameter. I'm using an iPad app called Musix to generate notes over OSC. Although the app has an OSCulator mode, I have been using the raw OSC as this gives me more info about the touches. The note events each have a pitch and then some other parameters related to the position of the finger on the note.

Currently I can generate monophonic MIDI and Kyma notes using OSCulator. What I
want to do now is have polyphony, and a forum search suggested that the Voice /
Index parameter can help with this.

I don't see much in the docs about how to do this though. Do you have any
suggestions how to use Voice in this context?

Thanks in advance

David Moss

camille
02-14-2011, 03:34 PM
Hi David,

The Voice / Index parameter works as a tag to differentiate the on/off state of each voices in a group of notes.
Suppose you receive a message with the following format:


/note {on/off} {pitch} {velocity} {voice}

And then you have these message sent to OSCulator (I am using integers for pitch and velocity for simplicity):



/note 1 64 127 0
/note 1 48 127 1
/note 1 72 127 2

/note 0 64 0 0
/note 1 72 0 2

/note 1 48 0 1


This will turn on notes 64, 48 and 72 on their respective voice indices (0, 1 and 2), and then turn off voices 0 and 2, and finally turn off the voice 1.

It is as if each notes of a chord has its own voice identifier. If you use a multitouch application that can send a message that transmits an identifier for each touch, then you can use that identifier to separate the note triggers of each touch.

The way the voice index works for MIDI is the same for Kyma, but with Kyma you have the added benefit that you can do glissandos, which is impossible in MIDI.

Please let me know if this answers you questions.
I would also be curious to know the exact format of the message Musix is sending to OSCulator (both OSCulator mode and advanced mode).

Best,
Cam

dejf_mk
03-02-2011, 09:23 PM
Hi Cam,
Sorry for such a late reply. I think I understand the voice parameter a bit better now.


Hi David,

Please let me know if this answers you questions.
I would also be curious to know the exact format of the message Musix is sending to OSCulator (both OSCulator mode and advanced mode).

Cam

Well the default OSC coming from the so called OSCulator mode is just note pitch with on and off triggers. But the advanced mode provides the pitch (as an integer), X and Y of the finger press inside the note and the X and Y grid position. I have used some Processing code to extract the note on/off, Pitch, X and Y finger press position, then send this to OSCulator to generate notes!

David

camille
03-02-2011, 11:14 PM
Awesome, thanks for the reply!