Re: GrandStaff vertical distance

[Lukas-Fabian Moser]

Hi,

> Thank you for this little function Lukas! It is very good and useful. Would
> it be possible to add to the list the choice for "square" or "bracket"? Some
> editions are using squares for grouping Violins 1-2.
Ah, do you mean an extra bracket? No problem. I also added the 
possibility to skip single staffs without having to issue a pair, e.g.
#'((extraBracket . 2) skip skip (brace . 3))
would mean: connect the first 2 staves with an extra bracket, then skip 
2 staves, then join the next 3 staves with a brace:

\version "2.19.82"

\layout {
  indent = 35
}

#(define (make-n-copies x n)
   (if (> n 0)
       (cons x (make-n-copies x (- n 1)))
       '()))

#(define (make-delimiter-hierarchy group-list)
   ; expects a list of pairs of the form (symbol . number) where
   ; symbol is either brace, noBrace or extraBracket
   ; number is the number of staves connected by a brace/extra 
bracket/nothing
   ; an arbitrary non-pair entry is interpreted as a single staff
   (apply append (map (lambda (entry)
                        (if (pair? entry)
                            (cond
                             ((equal? (car entry) 'brace)
                              (list (cons 'SystemStartBrace 
(make-n-copies 'staff (cdr entry)))))
                             ((equal? (car entry) 'extraBracket)
                              (list (cons 'SystemStartBracket 
(make-n-copies 'staff (cdr entry)))))
                             (else
                              (make-n-copies 'some-staff (cdr entry))))
                            '(some-staff)))
                   group-list)))



setBraces = #(define-music-function (group-list) (list?) #{
  \set StaffGroup.systemStartDelimiterHierarchy = 
#(make-delimiter-hierarchy group-list)
               #})

\new StaffGroup \with {
  \setBraces #'((extraBracket . 2) skip skip (brace . 3))
} <<
  \new Staff = "Staff_violinI" \with { instrumentName = #"Violin I" } { a }
  \new Staff = "Staff_violinII" \with { instrumentName = #"Violin II" } 
{ a }
  \new Staff = "Staff_viola" \with { instrumentName = #"Viola" } { a }
  \new Staff = "Staff_cello" \with { instrumentName = #"Cello" } { a }
  \new Staff = "Staff_bassd" \with { instrumentName = #"Double Bass" } 
{ a }
  \new Staff = "Staff_basst" \with { instrumentName = #"Triple Bass" } 
{ a }
  \new Staff = "Staff_bassq" \with { instrumentName = #"Quadruple Bass" 
} { a }
>>

> As suggested by David, it would be then enough "user-level" and complete to
> be documented, don't you think?
I'm afraid the threshold for additions to the set of "stock" functions 
shipped with Lilypond is quite high (regarding quality of code, 
bug-freeness, robustness, universality etc.). Maybe one could turn this 
into a snippet, but I've never done this.

Best
Lukas