%
%%%USAGE
% In the \score section do:
-% \unfoldRepeats \articulate <<
+% \articulate <<
% all the rest of the score
% >>
% or use the lilywrap script.
\version "2.16.0"
+#(use-modules (srfi srfi-1))
#(use-modules (ice-9 debug))
#(use-modules (scm display-lily))
% Start with 1/4 seconds == 1/240 minutes
#(define ac:maxTwiddleTime (ly:make-moment 1 240))
+% How long ordinary grace notes should be relative to their notated
+% duration. 9/40 is LilyPond's built-in behaviour for MIDI output
+% (though the notation reference says 1/4).
+#(define ac:defaultGraceFactor 9/40)
+
+% What proportion of an ordinary grace note's time should be stolen
+% from preceding notes (as opposed to stealing from the principal note).
+% Composers' intentions for this vary. Taking all from the preceding
+% notes is LilyPond's built-in behaviour for MIDI output.
+#(define ac:defaultGraceBackwardness 1)
+
% Internal variables, don't touch.
% (should probably be part of a context somehow)
% for no good reason.
#(define ac:currentDuration (ly:make-duration 2 0 1 1))
+% Amount of musical time (in whole notes) that we need to steal from the
+% next events seen.
+#(define ac:stealForward 0)
+
+% List of events in the output so far, in reverse order, from which we can
+% steal time.
+#(define ac:eventsBackward '())
+
+% Log events for the backward chain.
+#(define (ac:logEventsBackward music)
+ (music-map
+ (lambda (m)
+ (case (ly:music-property m 'name)
+ ((EventChord)
+ (set! ac:eventsBackward (cons m ac:eventsBackward))
+ m)
+ ((BarCheck SkipMusic)
+ (let ((wm (make-sequential-music (list m))))
+ (set! ac:eventsBackward (cons wm ac:eventsBackward))
+ wm))
+ (else
+ m)))
+ music))
+
+% Steal time from the backward chain. Adds to ac:stealForward (with a
+% warning) if it couldn't backward-steal all that was desired.
+#(define (ac:stealTimeBackward tosteal)
+ (if (<= tosteal 0)
+ #t
+ (if (null? ac:eventsBackward)
+ (begin
+ (ly:warning (_ "articulation failed to steal ~a note backward at beginning of music; stealing forward instead") tosteal)
+ (set! ac:stealForward (+ ac:stealForward tosteal)))
+ (let*
+ ((lastev (car ac:eventsBackward))
+ (levlen (ly:moment-main (ly:music-length lastev))))
+ (if (< tosteal levlen)
+ (begin
+ (ly:music-compress lastev (ly:make-moment (/ (- levlen tosteal) levlen)))
+ #t)
+ (begin
+ (if (any (lambda (z) (eq? 'NoteEvent (ly:music-property z 'name)))
+ (ly:music-property lastev 'elements))
+ (ly:warning (_ "stealing the entirety of a note's time")))
+ (set! (ly:music-property lastev 'elements) '())
+ (set! ac:eventsBackward (cdr ac:eventsBackward))
+ (ac:stealTimeBackward (- tosteal levlen))))))))
+
% Debugging: display a moment plus some text.
% Returns its moment argument so can be used in-line.
#(define (display-moment text m)
(context-spec-music
(make-property-set 'tempoWholesPerMinute tempo) 'Score))))
+%
+% Totally unfold repeats, so that the non-obvious sequencing doesn't
+% confuse us. This is necessary for time stealing to work, because
+% that relies on the sequence in which we see events matching their
+% audible sequence. Also unfold multi-measure rests to equivalent
+% skips, with preceding and following bar checks, so that time stealing
+% can change the length of the pause without falling foul of the
+% implicit bar checks.
+%
+#(define (ac:unfoldMusic music)
+ (music-map
+ (lambda (m)
+ (case (ly:music-property m 'name)
+ ((UnfoldedRepeatedMusic)
+ (let
+ ((body (ly:music-property m 'element))
+ (altl (ly:music-property m 'elements))
+ (rc (ly:music-property m 'repeat-count)))
+ (if (null? altl)
+ (make-sequential-music
+ (list-tabulate rc (lambda (i) (ly:music-deep-copy body))))
+ (let ((ealtl (if (> (length altl) rc) (take altl rc) altl)))
+ (make-sequential-music
+ (apply append!
+ (append!
+ (list-tabulate
+ (- rc (length ealtl))
+ (lambda (i) (list (ly:music-deep-copy body) (ly:music-deep-copy (car ealtl)))))
+ (map (lambda (alt) (list (ly:music-deep-copy body) alt))))))))))
+ ((MultiMeasureRestMusic)
+ (make-sequential-music
+ (list
+ (make-music 'BarCheck)
+ (make-music 'SkipMusic 'duration (ly:music-property m 'duration))
+ (make-music 'BarCheck))))
+ (else
+ m)))
+ (unfold-repeats music)))
+
% If there's an articulation, use it.
% If in a slur, use (1 . 1) instead.
% Treat phrasing slurs as slurs, but allow explicit articulation.
(if (null? es)
(begin
(set! (ly:music-property music 'elements) (reverse newelements))
- (cond
- ((not (any (lambda (m) (music-is-of-type? m 'rhythmic-event))
- newelements))
- actions)
- (ac:inTrill (cons 'trill actions))
- ((and (eq? factor ac:normalFactor) (or ac:inSlur ac:inPhrasingSlur))
- (append actions (list 'articulation '(1 . 1)) ))
- (else (append actions (list 'articulation factor)))))
+ (if
+ (not (any (lambda (m) (music-is-of-type? m 'rhythmic-event))
+ newelements))
+ actions
+ (append
+ (let ((st ac:stealForward))
+ (if (= st 0)
+ '()
+ (begin
+ (set! ac:stealForward 0)
+ (list 'steal st))))
+ actions
+ (cond
+ (ac:inTrill '(trill))
+ ((and (eq? factor ac:normalFactor) (or ac:inSlur ac:inPhrasingSlur))
+ (list 'articulation '(1 . 1)))
+ (else (list 'articulation factor))))))
; else part
(let ((e (car es))
(tail (cdr es)))
#(define (ac:articulate-chord music)
- (begin
- (cond
-
- ((eq? 'EventChord (ly:music-property music 'name))
+ (cond
+ ((eq? 'EventChord (ly:music-property music 'name))
+ (ac:logEventsBackward
(let loop ((actions (ac:getactions music)))
(if (null? actions)
(if (ly:moment<? (ly:make-moment 1/4) (ly:music-length music))
(lambda (z) (eq? 'NoteEvent (ly:music-property z 'name)))
(ly:music-property above 'elements)))
newmusic)))))
- ))))
+ ((steal)
+ (let
+ ((totallen (ly:moment-main (ly:music-length music)))
+ (steallen (cadr actions)))
+ (if (>= steallen totallen)
+ (begin
+ (if (any (lambda (z) (eq? 'NoteEvent (ly:music-property z 'name)))
+ (ly:music-property music 'elements))
+ (ly:warning (_ "stealing the entirety of a note's time")))
+ (set! ac:stealForward (- steallen totallen))
+ (make-sequential-music '()))
+ (begin
+ (ly:music-compress music (ly:make-moment (/ (- totallen steallen) totallen)))
+ (loop (cddr actions))))))
+ )))))
+
+ ((eq? 'GraceMusic (ly:music-property music 'name))
+ (let
+ ((first-ev
+ (call-with-current-continuation
+ (lambda (yield-fev)
+ (music-map
+ (lambda (m)
+ (if (eq? 'EventChord (ly:music-property m 'name))
+ (yield-fev m)
+ m))
+ music)
+ #f))))
+ (if first-ev
+ (let ((fev-pos (find-tail (lambda (m) (eq? m first-ev)) ac:eventsBackward)))
+ (if fev-pos
+ (set! ac:eventsBackward (cdr fev-pos))
+ (ly:warning (_ "articulation of grace notes has gone awry"))))))
+ (let*
+ ((gmus (ly:music-compress (ly:music-property music 'element)
+ (ly:make-moment ac:defaultGraceFactor)))
+ (glen (ly:moment-main (ly:music-length gmus))))
+ (ac:stealTimeBackward (* glen ac:defaultGraceBackwardness))
+ (set! ac:stealForward (+ ac:stealForward (* glen (- 1 ac:defaultGraceBackwardness))))
+ gmus))
+
+ ((memq (ly:music-property music 'name) '(BarCheck SkipMusic))
+ (let ((totallen (ly:moment-main (ly:music-length music)))
+ (steallen ac:stealForward))
+ (cond
+ ((= steallen 0)
+ (ac:logEventsBackward music))
+ ((< steallen totallen)
+ (set! ac:stealForward 0)
+ (ac:logEventsBackward
+ (ly:music-compress music (ly:make-moment (/ (- totallen steallen) totallen)))))
+ (else
+ (set! ac:stealForward (- steallen totallen))
+ (make-sequential-music '())))))
- ((eq? 'KeyChangeEvent (ly:music-property music 'name))
- (set! ac:current-key music)
- music
- )
+ ((eq? 'KeyChangeEvent (ly:music-property music 'name))
+ (set! ac:current-key music)
+ music)
- ((eq? 'PropertySet (ly:music-property music 'name))
- (ac:adjust-props (ly:music-property music 'symbol) music)
- music)
+ ((eq? 'PropertySet (ly:music-property music 'name))
+ (ac:adjust-props (ly:music-property music 'symbol) music)
+ music)
- (else music))
- ))
+ (else music)))
"Adjust times of note to add tenuto, staccato and
normal articulations.
"
- (set! music (event-chord-wrap! music parser))
- (music-map ac:articulate-chord music)
- )
+ (dynamic-wind
+ (lambda ()
+ (set! ac:stealForward 0)
+ (set! ac:eventsBackward '()))
+ (lambda ()
+ (music-map
+ ac:articulate-chord
+ (event-chord-wrap! (ac:unfoldMusic music) parser)))
+ (lambda ()
+ (or (= ac:stealForward 0)
+ (begin
+ (ly:warning (_ "articulation failed to steal ~a note at end of music") ac:stealForward)
+ (set! ac:stealForward 0)))
+ (set! ac:eventsBackward '()))))
% Override \afterGrace to be in terms of audio, not spacing.