Re: Vertical position of bar numbers

[David Wright]

On Mon 22 Feb 2016 at 11:23:29 (+0100), Simon Albrecht wrote:
> On 22.02.2016 05:09, David Wright wrote:
> >Having recently fixed a similar problem with bar numbering by moving
> >the Mark_engraver and adding Staff_collecting_engraver at Staff level,
> >I've run into the following: my bar numbers are running along the
> >skyline of my lyrics, as shown in the fabricated example.
> >
> >I like the 4 in the normal (default) position, and would prefer the
> >others to settle at the same level: below the upper lyrics, just above
> >the staff.
> >
> >As before, I've arrived at   4.4.3 Outside-staff objects   on p114 of
> >the Learning Manual (2.19.36) but, although there are default
> >priorities for bar numbers (and measure numbers, what's the
> >difference? apart from 650 in priority), lyrics are not mentioned
> >(as not grobs?).
> 
> Of course they consist of grobs (LyricText, LyricHyphen,
> LyricExtender and LyricSpace), but these grobs belong to a different
> context (Lyrics), so this method doesn’t apply here. Instead, you
> can move Bar_number_engraver from Score to the topmost Staff. See
> attached.

That's very informative, thanks. I'm still coming to terms with
juggling engravers in contexts. By searching Notation for \consists
I came across "Volta below chords" which is very like your answer here.

But sometimes I find the examples a little confusing. For example,
Learning 2.19.36 A3.3.3 on p161 shows how to put lyrics into a piano
staff. But why does it add \consists "Bar_engraver" to the Lyrics
context? I can't see any difference in the score when I remove
this line.

Having searched \consists, I thought it might be helpful to search
for \with examples, whereupon I hit p167 and the construct
\new Lyrics = "sopranos" \with {
  % this is needed for lyrics above a staff
  \override VerticalAxisGroup.staff-affinity = #DOWN
}
I can see a very subtle difference with and without this
\with { } clause, but there's no explanation of why it's needed.

Cheers,
David.