in Snippets - LilyPond

Contexts and engravers 373
0))
(set! (ambitus-start-key-sig ambitus)
(ly:context-property (ly:translator-context translator)
'keySignature)))))
#(define-method (update-ambitus-notes (ambitus ) note-grob)
"Update the upper and lower ambitus pithes of @var{ambitus}, using
@var{note-grob}."
;; Get the event that caused the note-grob creation
;; and check that it is a note-event.
(let ((note-event (ly:grob-property note-grob 'cause)))
(if (ly:in-event-class? note-event 'note-event)
;; get the pitch from the note event
(let ((pitch (ly:event-property note-event 'pitch)))
;; if this pitch is lower than the current ambitus lower
;; note pitch (or it has not been initialized yet),
;; then this pitch is the new ambitus lower pitch,
;; and conversely for upper pitch.
(for-each (lambda (direction pitch-compare)
(if (or (not (ambitus-note-pitch (ambitus-note ambitus direction)))
(pitch-compare pitch
(ambitus-note-pitch (ambitus-note ambitus dire
(begin
(set! (ambitus-note-pitch (ambitus-note ambitus direction))
pitch)
(set! (ambitus-note-cause (ambitus-note ambitus direction))
note-event))))
(list DOWN UP)
(list ly:pitch