A nice example for orchestral score set-up

[Trevor Bača]

New syntax in 2.7.19 to nest brackets and braces affords a couple of
nice features for orchestral score.

Here's an example:

%%%%%%%% START DELIMITER HIERARCHY SNIPPET %%%%%%

\version "2.7.19"

\score {
   <<
      \new StaffGroup <<
         \set StaffGroup.systemStartDelimiterHierarchy =
            #'(SystemStartBracket
                  (SystemStartSquare a b)
                  c
                  (SystemStartSquare d e))
         \new Staff {\clef treble s1}
         \new Staff {\clef treble s1}
         \new Staff {\clef treble s1}
         \new Staff {\clef tenor s1}
         \new Staff {\clef tenor s1}
      >>
      \new StaffGroup <<
         \override Score.SystemStartBracket #'collapse-height = #0.0
         \set StaffGroup.systemStartDelimiterHierarchy =
#'(SystemStartBracket a)
         \new Staff {\clef treble s1}
      >>
      \new StaffGroup <<
         \set StaffGroup.systemStartDelimiterHierarchy =
            #'(SystemStartBracket
               (SystemStartSquare a b)
               (SystemStartSquare c
                  (SystemStartSquare d e))
               f g)
         \new Staff {\clef treble s1}
         \new Staff {\clef treble s1}
         \new Staff {\clef treble s1}
         \new Staff {\clef treble s1}
         \new Staff {\clef treble s1}
         \new Staff {\clef tenor s1}
         \new Staff {\clef bass s1}
      >>
   >>
   \layout {
      raggedright = ##t
      \context {
         \Staff
         \remove Time_signature_engraver
      }
   }
}

%%%%%%%% END DELIMITER HIERARCHY SNIPPET %%%%%%

The snippet shows the staff set-up in The Rite of Spring at rehearsal
27. I've left instrument names out, so here's the instrumentation:

1. flutes
2. alto flute
3. b-flat clarinets
4. bassoons, divisi
5. bassoons, divisi

6. horns

7. violin solo
8. violin solo
9. 1st violins
10. 2nd violins, divisi
11. 2nd violins, divisi
12. violas
13. cellos

Three separate StaffGroups for the three sections of the orchestra;
the percussion do not play here.

The three sections each get a SystemStartBracket (including the horns
who here figure as a one-staff StaffGroup since no other brass is
playing). The flutes then get their own SystemStartSquare (new in
2.7.18), as do the divisi bassoons and the two solo violins.

The 1st and 2nd violins show nested SystemStartSquare, with the first
SystemStartSquare enclosing the 1st and 2nd violins as a group and the
second SystemStartSquare enclosing the divisi 2nd violins.

What enables all this is the syntax for
StaffGroup.systemStartDelimiterHierarchy, which is a type of labelled
tree. The nodes in the tree are arbitrary strings representing the
StaffGroup staves (from top to bottom). The node labels are either
SystemStartBracket, SystemStartBrace or SystemStartSquare.

The arbitrary strings you chose to use for staff tokens can be
whatever you want: I've used lowercase letters here, but they could
just as easily be "foo" or "bar", too.

Whitespace also doesn't matter very much in the specification for
StaffGroup.systemStartDelimiterHierarchy so you can indent however
best represents the delimiter nesting.

There's a subtlety: note the overriding of Score.SystemStartBracket
#'collapse-height to #0.0 in about the middle of the example. That
directive is there to make sure that the one-staff horns' StaffGroup
gets a proper bracket: commenting out the directive makes the horns'
bracket go away and leaves the brass looking a bit undressed. (Note,
too, that #'collapse-height needs to be set at the level of the Score
rather than the level of the StaffGroup.)

SystemStartSquare will get a bit more weight in some later release and
we'll also need to check to make sure that instrument names (not
included in this example) play nicely with delimiter nesting. Overall,
the feature affords a nice bit flexibility and I hope it comes in
handy laying out work for orchestra.



--
Trevor Bača
address@hidden

delimiter-nesting.png
Description: PNG image