Re: Part combiner: separate split state and voice names

[Keith OHara]

On Sat, 29 Nov 2014 14:44:48 -0800, Dan Eble <address@hidden> wrote:

> On Nov 29, 2014, at 16:46 , Keith OHara <address@hidden> wrote:
> > Dan Eble <dan <at> faithful.be> writes:
> >
> > > I would like the Scheme portion of the part
> > > combiner to dictate the names of the voices to use at every moment.
> >
> > Simply letting us specify the Voices _once_ for the whole output of
> > \partcombine would help a lot.
>
> It would, and I’m glad you’re encouraging me to dig up my ancient patch to do 
> that, but I wasn’t thinking of making any user-visible changes in the scope of 
> the work suggested in this thread.  (That could come later.)
Well, if I can't use it, I am less motivated to review it.

I am eager for either nameable outputs from \partcombine, or VoiceGroup, in 
LilyPond so we can have a stable and functional \partcombineUp/Down.

> > Include an example in your patch, where we want to rearrange the routing
> > of soloI, unison, etc., to Voices mid-piece.
>
> This suggestion was motivated by recent work on cases in which both parts are 
> resting.  If the desired action is to route only one of the voices to the 
> shared voice, the Scheme half currently can only say “unisilence” and the 
> Part_combine_iterator picks a voice.  The problem is that sometimes it doesn’t 
> pick well.  It seems that the Scheme half has the information to make a better 
> decision.

Oh, so you meant let the Scheme portion dictate to partcombine_iterator which 
_input_ voice, as it iterates the music expression produced by \partcombine, to 
use.

That makes more sense.  However, the current problem with the iterator picking which 
input part to route to output Voice "shared", seems best solved by your current 
patch, that marks these situations as 'apart-silence' whenever there is a difference 
between the input parts.