On 2020-12-19 3:14 pm, Pine, Zachary V wrote:
Hello Community,
I'm writing a piano piece across three staves. Sometimes I would like
to use autochange to engrave material on the top two staves, other
times across the bottom two. I know autochange works by default on
staves named "up" and "down".
Is there any way to override the names of the staves autochange looks
for? Perhaps there is another solution I'm not seeing other than
manually inputting \change Staff everytime.
Here is one approach, although I cannot be certain it covers all edge
cases:
%%%%
\version "2.20.0"
#(define (symbol-pair? arg)
(and (pair? arg) (symbol? (car arg)) (symbol? (cdr arg))))
#(define (symbol-pair-list? arg)
(and (list? arg) (every symbol-pair? arg)))
replaceContextChanges =
#(define-music-function
(replacements music)
(symbol-pair-list? ly:music?)
(define (proc music)
(if (music-is-of-type? music 'context-specification)
(ly:music-set-property! music 'context-id
(let* ((id (ly:music-property music 'context-id))
(sym (string->symbol id)))
(if (eq? "" id) id ; Sometimes context-id is an empty string.
(symbol->string (ly:assoc-get sym replacements sym))))))
(if (music-is-of-type? music 'auto-change-instruction)
(ly:music-set-property! music 'context-change-list
(map (lambda (p) (let ((mom (car p)) (sym (cdr p)))
(cons mom (ly:assoc-get sym replacements sym))))
(ly:music-property music 'context-change-list))))
music)
#{ \musicMap #proc #music #})
<< \new Staff = upper { \clef treble s1*3 }
\new Staff = middle { \clef alto s1*3 }
\new Staff = lower { \clef bass
\replaceContextChanges #'((down . lower) (up . middle))
\autochange { a4 b d' e' }
\replaceContextChanges #'((down . middle) (up . upper))
\autochange { a4 b d' e' }
\replaceContextChanges #'((down . upper) (up . lower))
\autochange { a4 b d' e' }
} >>
%%%%
-- Aaron Hill
