4 texidoc = "overriding the molecule callback can also be used to draw a
5 box around arbitrary grobs.
7 TODO: check whether the corners are really correct.
9 TODO: circled molecules.
14 #(define (make-molecule-boxer callback)
15 (define (molecule-boxer grob)
20 (x-ext (widen-interval (ly-get-molecule-extent mol 0) box-padding))
21 (y-ext (widen-interval (ly-get-molecule-extent mol 1) box-padding))
23 (x-rule (box-molecule (widen-interval x-ext rule-thick)
25 (y-rule (box-molecule (cons 0 rule-thick) y-ext))
28 (set! mol (ly-combine-molecule-at-edge mol 0 1 y-rule (* 0.5 box-padding)))
29 (set! mol (ly-combine-molecule-at-edge mol 0 -1 y-rule (* 0.5 box-padding)))
30 (set! mol (ly-combine-molecule-at-edge mol 1 1 x-rule 0.0))
31 (set! mol (ly-combine-molecule-at-edge mol 1 -1 x-rule 0.0))
39 \score { \notes \relative c'' {
41 \property Voice.TextScript \override #'molecule-callback =
42 #(make-molecule-boxer Text_item::brew_molecule)
46 \property Voice.Stem \override #'molecule-callback =
47 #(make-molecule-boxer Stem::brew_molecule)
49 \property Score.RehearsalMark \override #'molecule-callback =
50 #(make-molecule-boxer Text_item::brew_molecule)
53 \property Voice.Stem \revert #'molecule-callback