Thomas Ruedas wrote:
Hi,
for many years I have used a hack for marking a change of hand in
polyphonic piano music that I had been pointed to some 11 years ago on
this group, and it had worked fine. Unfortunately, no more.
I updated this to the attached version about a year ago.
It runs with 2.20, 2.22, 2.24 and seems OK with 2.25.24.
Cheers,
Robin
\version "2.24.0"
% compatibility changes: u15k0830 u23k0114
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +thumb bracket
#(define (make-thumb-bracket-props location spec-str settings-alist)
(define (inchar? index) (> (string-length spec-str) index))
(define (inchar index) (string-ref spec-str index))
(define (char->dir ch)
(case (char-upcase ch) ((#\R) 1) ((#\L) -1) (else 0)))
(define (char->digit ch)
(if (char-numeric? ch) (- (char->integer ch) (char->integer #\0)) 0))
(define (inhit->1 key-str) (if (string-contains spec-str key-str) 1 0))
(define (get key) (assq-ref settings-alist key))
(define (warn p1 p2) (ly:input-warning location
(G_ " bad thumb-bracket: ~a ~a~a~a") p1 "\"" p2 "\"")) ; cf
(let* ( ;% decode spec
(vdir (if (inchar? 0) (char->dir (inchar 0)) 0))
(vbigger (* 0.5 (if (inchar? 1) (char->digit (inchar 1)) 0)))
(vfurther (* 0.5 (if (inchar? 2) (char->digit (inchar 2)) 0)))
(hcloser (* 0.5 (if (inchar? 3) (char->digit (inchar 3)) 0)))
(hrear (* 0.5 (if (inchar? 4) (char->digit (inchar 4)) 0)))
(vbigger+ (* 5 (string-count spec-str #\|)))
(posdir ((if (string-contains spec-str "*") - +) vdir))
(hcloser? (eq? (string-contains spec-str "!") #f))
(vtip=? (string-contains spec-str "="))
(hdir-req (- (inhit->1 "]") (inhit->1 "[")))
(closed? (char-lower-case? (inchar 0))))
(if (zero? vdir) (begin (warn "first char in" spec-str) '())
(let* ( ;% collect settings
(hdir-init (get 'hdir-init)) (htip (get 'htip))
(vtip (get (if vtip=? 'vtip= 'vtip)))
(vstem (get 'vstem)) (vmin (get 'vmin)) (hvernier (get 'hvernier))
(vO 0) (hO 0) (hpad-base 0.5) ;% givens
(hdir (if (zero? hdir-req) hdir-init hdir-req))
(hflip? (positive? hdir))
(h-interval
(if (positive? hdir) (cons hO (+ htip hrear)) (cons (- hrear) htip)))
(vsize (+ vtip (if closed? vtip vstem) vbigger vbigger+))
(vsize+ (if (and closed? (< vsize vmin)) (- vmin vsize) 0))
(vshift (+ vfurther vtip (* 0.5 vsize+)))
(bracket (lambda (grob) (let* ( ;% collect chord range from grob
(vnote-lo-hi (ly:grob-property grob 'positions))
(vnote ((if (eq? posdir 1) cdr car) vnote-lo-hi)))
(grob-interpret-markup grob (markup #:translate (cons
((if (positive? hdir) - +) hvernier) (- vnote (* vdir vshift)))
#:combine #:draw-line (cons htip vO) #:combine
#:translate (cons hO (if closed? (* vdir (+ vsize vsize+)) vO))
#:draw-line (cons htip vO)
#:translate (cons (if (positive? hdir) htip hO) vO)
#:draw-line (cons hO (* vdir (+ vsize vsize+)))))))))
;% alist of props for misusing Arpeggio as a thumb bracket
`((stencil . ,bracket)
(X-extent . ,h-interval)
(padding . ,((if hcloser? - +) hpad-base hcloser))
(direction . ,hdir)
(thickness . ,(get 'weight)))))))
thumbBracketEx = #(define-music-function
(spec settings) (string? list?)
(let* (
(props (make-thumb-bracket-props (*location*) spec settings)))
(define (get key) (assq-ref props key))
(if (null? props) #{ #} ;% abort without bracket
#{
\once \override Arpeggio.stencil = #(get 'stencil)
\once \override Arpeggio.X-extent = #(get 'X-extent)
\once \override Arpeggio.padding = #(get 'padding)
\once \override Arpeggio.direction = #(get 'direction)
\once \override Arpeggio.thickness = #(get 'thickness)
$(make-music 'EventChord 'elements (list (make-music 'ArpeggioEvent)))
#})))
thumbBracket = #(define-music-function (spec) (string?)
(let ((settings thumbBracketSettings)) ;% as Defaults, or user defined
#{ \thumbBracketEx $spec $settings #}))
thumbBracketDefaults = #(quasiquote(
(hdir-init . ,LEFT) ;% usual placement wrt note: on RIGHT or LEFT
(weight . 1.5 ) ;% line thickness
(htip . 0.8 ) ;% horizontal length of bracket tip
(vtip . 0.75 ) ;% usual vertical overlap beyond notehead centre
(vtip= . 0.30 ) ;% alternative vertical overlap
(vstem . 1.25 ) ;% length of an unextended open bracket (excl. tip)
(vmin . 0.6 ) ;% minimum length of a closed bracket
(hvernier . 0.2 ) ;% horizontal quasi-extra-offset
))
thumbBracketSettings = \thumbBracketDefaults
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% -thumb bracket
