;;;; You should have received a copy of the GNU General Public License
;;;; along with LilyPond. If not, see <http://www.gnu.org/licenses/>.
+(define-public (ly:make-listener callback)
+ "This is a compatibility wrapper for creating a \"listener\" for use
+with @code{ly:add-listener} from a @var{callback} taking a single
+argument. Since listeners are equivalent to callbacks, this is no
+longer needed."
+ callback)
(define-public (Measure_counter_engraver context)
"This engraver numbers ranges of measures, which is useful in parts as an
(make-engraver
(listeners
- ((measure-counter-event engraver event)
- (cond
- ((and (= START (ly:event-property event 'span-direction))
- go?)
- (set! stop? #t)
- (ly:input-warning
- (ly:event-property event 'origin)
- "count not ended before another begun"))
- ((= START (ly:event-property event 'span-direction))
- (set! go? #t)
- ;; initialize one less so first measure receives a count spanner
- (set! last-measure-seen
- (1- (ly:context-property context 'currentBarNumber))))
- ((= STOP (ly:event-property event 'span-direction))
- (set! stop? #t)
- (set! go? #f)))))
+ ((measure-counter-event engraver event)
+ (cond
+ ((and (= START (ly:event-property event 'span-direction))
+ go?)
+ (set! stop? #t)
+ (ly:input-warning
+ (ly:event-property event 'origin)
+ "count not ended before another begun"))
+ ((= START (ly:event-property event 'span-direction))
+ (set! go? #t)
+ ;; initialize one less so first measure receives a count spanner
+ (set! last-measure-seen
+ (1- (ly:context-property context 'currentBarNumber))))
+ ((= STOP (ly:event-property event 'span-direction))
+ (set! stop? #t)
+ (set! go? #f)))))
((process-music trans)
(let ((col (ly:context-property context 'currentCommandColumn))
(set! (ly:grob-property c 'count-from) (+ counter elapsed))
(set! count-spanner c)
(set! elapsed (1+ elapsed))))))
- (set! last-measure-seen current-bar)))
+ (set! last-measure-seen current-bar)))
((finalize trans)
(if go?
(ly:grob-suicide! count-spanner)
(set! count-spanner '())
(ly:warning "measure count left unfinished")))))))
+
+(ly:register-translator
+ Measure_counter_engraver 'Measure_counter_engraver
+ '((grobs-created . (MeasureCounter))
+ (events-accepted . (measure-counter-event))
+ (properties-read . (currentCommandColumn
+ measurePosition
+ currentBarNumber))
+ (properties-written . ())
+ (description . "\
+This engraver numbers ranges of measures, which is useful in parts as an
+aid for counting repeated measures. There is no requirement that the
+affected measures be repeated, however. The user delimits the area to
+receive a count with @code{\\startMeasureCount} and
+@code{\\stopMeasureCount}.")))
+
+(ly:register-translator
+ Span_stem_engraver 'Span_stem_engraver
+ '((grobs-created . (Stem))
+ (events-accepted . ())
+ (properties-read . ())
+ (properties-written . ())
+ (description . "Connect cross-staff stems to the stems above in the system")))
+
+(define-public (Merge_rests_engraver context)
+"Engraver to merge rests in multiple voices on the same staff.
+
+This works by gathering all rests at a time step. If they are all of the same
+length and there are at least two they are moved to the correct location as
+if there were one voice."
+
+ (define (is-single-bar-rest? mmrest)
+ (eqv? (ly:grob-property mmrest 'measure-count) 1))
+
+ (define (is-whole-rest? rest)
+ (eqv? (ly:grob-property rest 'duration-log) 0))
+
+ (define (mmrest-offset mmrest)
+ "For single measures they should hang from the second line from the top
+ (offset of 1). For longer multimeasure rests they should be centered on the
+ middle line (offset of 0).
+ NOTE: For one-line staves full single measure rests should be positioned at
+ 0, but I don't anticipate this engraver's use in that case. No errors are
+ given in this case."
+ (if (is-single-bar-rest? mmrest) 1 0))
+
+ (define (rest-offset rest)
+ (if (is-whole-rest? rest) 1 0))
+
+ (define (rest-eqv rest-len-prop)
+ "Compare rests according the given property"
+ (define (rest-len rest) (ly:grob-property rest rest-len-prop))
+ (lambda (rest-a rest-b)
+ (eqv? (rest-len rest-a) (rest-len rest-b))))
+
+ (define (rests-all-unpitched rests)
+ "Returns true when all rests do not override the staff-position grob
+ property. When a rest has a position set we do not want to merge rests at
+ that position."
+ (every (lambda (rest) (null? (ly:grob-property rest 'staff-position))) rests))
+
+ (define (merge-mmrests rests)
+ "Move all multimeasure rests to the single voice location."
+ (if (all-equal rests (rest-eqv 'measure-count))
+ (merge-rests rests mmrest-offset)))
+
+ (define (merge-rests rests offset-function)
+ (let ((y-offset (offset-function (car rests))))
+ (for-each
+ (lambda (rest) (ly:grob-set-property! rest 'Y-offset y-offset))
+ rests))
+ (for-each
+ (lambda (rest) (ly:grob-set-property! rest 'transparent #t))
+ (cdr rests)))
+
+ (define has-one-or-less (lambda (lst) (or (null? lst) (null? (cdr lst)))))
+ (define has-at-least-two (lambda (lst) (not (has-one-or-less lst))))
+ (define (all-equal lst pred)
+ (or (has-one-or-less lst)
+ (and (pred (car lst) (cadr lst)) (all-equal (cdr lst) pred))))
+
+ (let ((curr-mmrests '())
+ (mmrests '())
+ (rests '()))
+ (make-engraver
+ ((start-translation-timestep translator)
+ (set! rests '())
+ (set! curr-mmrests '()))
+ (acknowledgers
+ ((rest-interface engraver grob source-engraver)
+ (cond
+ ((ly:context-property context 'suspendRestMerging #f)
+ #f)
+ ((grob::has-interface grob 'multi-measure-rest-interface)
+ (set! curr-mmrests (cons grob curr-mmrests)))
+ (else
+ (set! rests (cons grob rests))))))
+ ((stop-translation-timestep translator)
+ (if (and
+ (has-at-least-two rests)
+ (all-equal rests (rest-eqv 'duration-log))
+ (rests-all-unpitched rests))
+ (merge-rests rests rest-offset))
+ (if (has-at-least-two curr-mmrests)
+ (set! mmrests (cons curr-mmrests mmrests))))
+ ((finalize translator)
+ (for-each merge-mmrests mmrests)))))
projects / lilypond.git / blobdiff