Re: Extract notes from chords, with silence when there are none

[mskala]

On Wed, 16 Sep 2015, David Kastrup wrote:
> > Just to clarify, in the case of 3-voice music, how would you expect it to
> > deal with a 2 note chord?
> >
> > One note to Treble, one to Bass, or one in Treble, one in Alto, or... what?
>
> As I read him, he does not care.  First note anywhere, second note
> anywhere else, skip in the remaining expression.  This is for midi.

That's right.  I just want any two notes that play simultaneously to be
returned by separate index values into the extraction function, and any
other index values to return something that will be silent (either a skip
or a rest).  The typesetting of human-readable score will be from the
original single polyphonic voice; the splitting is only for MIDI, only to
separate the pitch-bend data for different notes, and the split channels
will be played using identical settings, so the exact assignment of notes
to index values (channels) can be arbitrary.

I would expect that the easiest way to do the note assignment would be
what I described in my initial message - change the "extract" script to
return silence instead of the last note in the data structure, when the
index is greater than the number of notes.  Then with two simultaneous
notes they will be returned by index values 1 and 2, and silence returned
by index 3.

I don't need to deal with cases like << { d''1 } { c'2 c'2 } >>, because
the input really is a single polyphonic voice.  Notes will all start and
stop together, only the number of notes changes.

FWIW, I'm aware of the script at http://x31eq.com/lilypond/, which
attempts to do better microtonality with LilyPond and MIDI Tuning Standard
messages, but it's not suitable for my needs because I'm sending the data
to a very simple MIDI device that doesn't understand MTS, only pitch bend.
(And I think it would require separating the notes into channels first
anyway.)

-- 
Matthew Skala
address@hidden                 People before principles.
http://ansuz.sooke.bc.ca/