Re: volta repeat with and without alternative ending

[Brian Barker]

At 10:13 24/06/2015 -0700, Abraham Noname wrote:
> On Wed, Jun 24, 2015 at 9:48 AM, Gergely Kontra [via Lilypond] wrote:
> > I am engraving an orchestral score, and ran into the following: one 
> > staff has volta repeat with alternative ending, but the other staff 
> > has no alternate ending. When I engrave the score for the 
> > conductor, strange thing happens (one staff is shorter, that the 
> > other) I also would like to engrave scores for violin and viola, 
> > and those notes are in separate files. Viola part should not be 
> > aware of the alternative block in violin IMHO. So, how should I 
> > write this piece to be correct? (online version: http://lilybin.com/mpasgy/4)
> >
> > \version "2.18.2"
> > \language "deutsch"
> >
> > violin = \relative c'' {
> >     \repeat volta 2 { c4 d e f | }
> >     \alternative {
> >       { c2 e | }
> >       { f2 g | }
> >     }
> >     c1
> > }
> >
> > viola = \relative c' {
> >     \repeat volta 2 { c4 d e f |
> >     c2 c }
> >     c1
> > }
> >
> > \score {
> >   <<
> >     \new Staff \violin
> >     \new Staff { \clef alto \viola }
> >   >>
> >   \layout { }
> > }
>
> I believed I answered this already on the bugs list here: 
> http://lilypond.1069038.n5.nabble.com/repeat-volta-2-td178090.html#a178094

I don't think you did. You claim there that "looking at it by the raw 
musical content, I see 4 bars for violin and only 3 for viola", but 
you don't explain why you see that as a problem. You are counting 
notation, not actual bars as played. Why does it matter that, say, 
ten played bars might be expressed as only five bars repeated? And 
your expansion of the parts there is incorrect: you have included the 
first time bar the second time around for the violin, suggesting six 
bars played in total, whereas there are actually only five.

> It got me thinking, though. Why don't you want the viola to have the 
> same \repeat volta 2 { ... } \alternative { { ... } { ... } } 
> structure, too? If you are making individual part scores, then 
> you're going to need it, IMHO.

That's your dispute with the original questioner, who prefers the 
viola players not to see what is going on in other parts. (I happen 
to agree with you: that it is clearer if the identical first and 
second time bars in the viola part are laid out in the same way as in 
other parts. I *think* (she doesn't say this explicitly) that Elaine 
Gould agrees.)

> If that's really not what you want, what should the viola be playing 
> during the violin's 2nd ending?

Oh, that's easy and evident: exactly what is written. The last 
(second) bar of the viola part's repeat coincides with the second 
time bar in the violin part.

Brian Barker