Re: GrandStaff vertical distance

[Aaron Hill]

On 2018-10-09 7:15 am, foxfanfare wrote:
> Hi all,
>
> I'm trying to configure a template for my orchestral works but I have a
> problem with the GrandStaff vertical distance. You can take the 
> template
> proposed in the manual to see the problem:
> http://lilypond.org/doc/v2.19/Documentation/learning/orchestra-choir-and-piano
>
> You can see in the string section, between Violin II and Viola, an 
> extra
> space is added due to the use of the brace of the GrandStaff. (Same 
> problem
> with the Alti group in the choir).
>
> I have made some ressearch in scores and also in Gould's book, this is 
> verry
> unconventional. A space is added between the StaffGroups, but should 
> not
> appear within the same family.
>
> How could you properly change that? I tried with:
> \override GrandStaff.StaffGrouper.staffgroup-staff-spacing = #'(
>         (basic-distance . 9)
>         (minimum-distance . 7)
>         (padding . 1)
>         (stretchability . 5))
>
> But this will move above AND bellow the GrandStaff. Here is in my score 
> the
> illustration of the problem:
> distance.png 
> <http://lilypond.1069038.n5.nabble.com/file/t5604/distance.png>

I can see the same behavior given the default settings; but if you are 
explicit about your spacing parameters, then it seems the spacing can be 
forced to be even.  Consider the following contrived example:

%%%%
\version "2.19.82"

notes = { <c' b' a''>1 }
\score {
  <<
    \new Staff \notes
    \new Staff \notes
    \new StaffGroup <<
      \new Staff \notes
      \new Staff \notes
      \new GrandStaff <<
        \new Staff \notes
        \new Staff \notes
      >>
      \new Staff \notes
      \new Staff \notes
    >>
    \new Staff \notes
    \new Staff \notes
  >>
  \layout {
    \context { \Score
      \override StaffGrouper.staffgroup-staff-spacing.basic-distance = 
#9
    }
  }
}
%%%%

The default basic-distance for staff groups seems to be roughly 11, but 
staves normally prefer a basic-distance around 9.  That override above 
seems to be enough to make my contrived example show (nearly) consistent 
spacing.

Another thing that worked was setting the staff-staff-spacing at the 
\Staff level:

%%%%
  \layout {
    \context { \Staff
      \override VerticalAxisGroup.staff-staff-spacing.basic-distance = 
#9
    }
  }
%%%%

However, this doesn't really make sense to me.  Maybe someone with a 
better understanding of the internals could determine whether this is 
expected behavior.  But it seems that the staff-staff-spacing override 
trumps staffgroup-staff-spacing, which means one loses a degree of 
freedom if you do want to adjust those independently.  Then again, all 
the staves are in the same system, so perhaps staff-staff-spacing really 
should apply regardless of whether or not the staves belong to staff 
groups.


-- Aaron Hill