+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;; accidentals
+
+(define-public (set-accidentals-properties extra-natural
+ auto-accs auto-cauts
+ context)
+ (context-spec-music
+ (make-sequential-music
+ (append (if (boolean? extra-natural)
+ (list (make-property-set 'extraNatural extra-natural))
+ '())
+ (list (make-property-set 'autoAccidentals auto-accs)
+ (make-property-set 'autoCautionaries auto-cauts))))
+ context))
+
+(define-public (set-accidental-style style . rest)
+ "Set accidental style to STYLE. Optionally takes a context argument,
+e.g. 'Staff or 'Voice. The context defaults to Voice, except for piano styles, which
+use GrandStaff as a context. "
+ (let ((context (if (pair? rest)
+ (car rest) 'Staff))
+ (pcontext (if (pair? rest)
+ (car rest) 'GrandStaff)))
+ (ly:export
+ (cond
+ ;; accidentals as they were common in the 18th century.
+ ((equal? style 'default)
+ (set-accidentals-properties #t '(Staff (same-octave . 0))
+ '() context))
+ ;; accidentals from one voice do NOT get cancelled in other voices
+ ((equal? style 'voice)
+ (set-accidentals-properties #t '(Voice (same-octave . 0))
+ '() context))
+ ;; accidentals as suggested by Kurt Stone, Music Notation in the 20th century.
+ ;; This includes all the default accidentals, but accidentals also needs cancelling
+ ;; in other octaves and in the next measure.
+ ((equal? style 'modern)
+ (set-accidentals-properties #f '(Staff (same-octave . 0) (any-octave . 0) (same-octave . 1))
+ '() context))
+ ;; the accidentals that Stone adds to the old standard as cautionaries
+ ((equal? style 'modern-cautionary)
+ (set-accidentals-properties #f '(Staff (same-octave . 0))
+ '(Staff (any-octave . 0) (same-octave . 1))
+ context))
+ ;; Multivoice accidentals to be read both by musicians playing one voice
+ ;; and musicians playing all voices.
+ ;; Accidentals are typeset for each voice, but they ARE cancelled across voices.
+ ((equal? style 'modern-voice)
+ (set-accidentals-properties #f
+ '(Voice (same-octave . 0) (any-octave . 0) (same-octave . 1)
+ Staff (same-octave . 0) (any-octave . 0) (same-octave . 1))
+ '()
+ context))
+ ;; same as modernVoiceAccidental eccept that all special accidentals are typeset
+ ;; as cautionaries
+ ((equal? style 'modern-voice-cautionary)
+ (set-accidentals-properties #f
+ '(Voice (same-octave . 0))
+ '(Voice (any-octave . 0) (same-octave . 1)
+ Staff (same-octave . 0) (any-octave . 0) (same-octave . 1))
+ context))
+ ;; stone's suggestions for accidentals on grand staff.
+ ;; Accidentals are cancelled across the staves in the same grand staff as well
+ ((equal? style 'piano)
+ (set-accidentals-properties #f
+ '(Staff (same-octave . 0)
+ (any-octave . 0) (same-octave . 1)
+ GrandStaff (any-octave . 0) (same-octave . 1))
+ '()
+ pcontext))
+ ((equal? style 'piano-cautionary)
+ (set-accidentals-properties #f
+ '(Staff (same-octave . 0))
+ '(Staff (any-octave . 0) (same-octave . 1)
+ GrandStaff (any-octave . 0) (same-octave . 1))
+ pcontext))
+ ;; do not set localKeySignature when a note alterated differently from
+ ;; localKeySignature is found.
+ ;; Causes accidentals to be printed at every note instead of
+ ;; remembered for the duration of a measure.
+ ;; accidentals not being remembered, causing accidentals always to be typeset relative to the time signature
+ ((equal? style 'forget)
+ (set-accidentals-properties '()
+ '(Staff (same-octave . -1))
+ '() context))
+ ;; Do not reset the key at the start of a measure. Accidentals will be
+ ;; printed only once and are in effect until overridden, possibly many
+ ;; measures later.
+ ((equal? style 'no-reset)
+ (set-accidentals-properties '()
+ '(Staff (same-octave . #t))
+ '()
+ context))
+ (else
+ (ly:warn "Unknown accidental style: ~S" (symbol->string style))
+ (make-sequential-music '()))))))