1 ;;;; This file is part of LilyPond, the GNU music typesetter.
3 ;;;; Copyright (C) 2009--2011 Carl Sorensen <c_sorensen@byu.edu>
5 ;;;; LilyPond is free software: you can redistribute it and/or modify
6 ;;;; it under the terms of the GNU General Public License as published by
7 ;;;; the Free Software Foundation, either version 3 of the License, or
8 ;;;; (at your option) any later version.
10 ;;;; LilyPond is distributed in the hope that it will be useful,
11 ;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
12 ;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 ;;;; GNU General Public License for more details.
15 ;;;; You should have received a copy of the GNU General Public License
16 ;;;; along with LilyPond. If not, see <http://www.gnu.org/licenses/>.
18 ;;; specify time signature default settings
23 ;;; (time-signature . default-properties) entries.
25 ;;; where default-properties is an alist containing information about the
26 ;;; time signature. Each default-properties set can contain the
27 ;;; following entries:
29 ;;; (baseMoment . (numerator . denominator))
30 ;;; (beatStructure . structure-list)
31 ;;; (beamExceptions . (alist of beam exceptions that don't follow beats))
33 ;;; The alist of beam exceptions has the following entries:
35 ;;; (end . grouping-rules)
36 ;;; (subdivide . grouping-rules) (not yet implemented, reserved for future use)
38 ;;; grouping-rules is an alist containing (beam-type . grouping-list) entries
40 ;;; beam-type is (numerator . denominator)
41 ;;; grouping-list is a list that specifies the
42 ;;; number of stems of the given duration that are grouped in a beamed unit.
43 ;;; For an exception, the duration used is beam-type. For measureBeats,
44 ;;; the duration used is baseMoment.
46 ;;; If an exception is specified for a given beam-type, it will apply to all
47 ;;; beams of shorter durations that don't have an individual exception, so
48 ;;; ((1 . 8) . (3 3 2))
49 ;;; will cause all primary beams to be broken at 3/8, 6/8, and 8/8.
51 ;;; ((1. 32) . (16 8 4 4))
52 ;;; will cause all 1/32, 1/64, and 1/128 beams to be broken at 1/2, 3/4,
55 ;;; If no values are given for baseMoment and measureBeats, default values
57 ;;; baseMoment gets the value (ly:make-moment 1 time-signature-denominator)
58 ;;; beatStructure gets a list of (3 3 3 ...), where the number of entries is the
59 ;;; number of beats, each containing 3 base-moments, if the time
60 ;;; signature numerator is greater than 3 and divisible by 3, and
61 ;;; a list of (1 1 1 ...), where the number of entries is the
62 ;;; number of base moments in a measure otherwise.
64 ;;; NOTE: numerator is kept in beam-type because of
65 ;;; tuplets, e.g. (2 . 24) = (2 . 3) * (1 . 8)
66 ;;; for eighth-note triplets.
68 (define-public default-time-signature-settings
71 ;; use defaults, but end beams with 32nd notes each 1 4 beat
73 ((beamExceptions . ((end . (((1 . 32) . (8 8 8 8))))))))
75 ;; in 2/4, 2/8 and 2/16 time:
76 ;; use defaults, so no entries are necessary
79 ;; use defaults, but end beams with 32nd notes and higher each 1 4 beat
82 ((beamExceptions . ((end . (((1 . 32) . (8 8 8 8 8 8))))))))
85 ;; use defaults, but combine all beats into a unit if possible
87 ;; set all beams to end on beats, but 1 8 to beam entire measure
88 ;; in order to avoid beaming every beam type for the entire measure, we set
89 ;; triplets back to every beat.
91 ((beamExceptions . ((end . (((1 . 8) . (6)) ;1/8 note whole measure
92 ((1 . 12) . (3 3 3)))))))) ;Anything shorter by beat
95 ;; beam entire measure together
96 ((3 . 8) . ((beamExceptions . ((end . (((1 . 8) . (3))))))))
99 ;; use defaults -- no entries necessary
102 ;; use defaults, but end beams with 16th notes or finer each 1 4 beat
104 ((beamExceptions . ((end . (((1 . 16) . (4 4 4 4 4 4 4 4))))))))
106 ;; in 4 4 (common) time:
107 ;; use defaults, but combine beats 1,2 and 3,4 if only 8th notes
108 ;; NOTE: Any changes here need to be duplicated in
109 ;; ly/engraver-init.ly where the default time signature is set
112 ((beamExceptions . ((end . (((1 . 8) . (4 4)) ; 1/8 notes half measure
113 ((1 . 12) . (3 3 3 3)))))))) ;Anything shorter by beat
116 ;; combine beats 1 and 2, so beam in 2
117 ((4 . 8) . ((beatStructure . (2 2))))
119 ;; in 4/8 and 4/16 time:
120 ;; use defaults, so no entries necessary
123 ;; use defaults, but end beams with 32nd or finer each 1/4 beat
125 ((beamExceptions . ((end . (((1 . 16) . (4 4 4 4 4 4))))))))
128 ;; use defaults, so no entries necessary
131 ;; use defaults, so no entries necessary
134 ;; use defaults, but end beams with 32nd or finer each 1 4 beat
136 ((beamExceptions . ((end . (((1 . 32) . (8 8 8 8 8 8 8 8))))))))
139 ;; use defaults, so no entries necessary
142 ;; use defaults, so no entry necessary
145 ;; use defaults, but end beams with 32nd or finer notes each 1 4 beat
147 ((beamExceptions . ((end . (((1 . 32) . (8 8 8 8 8 8 8 8 8 8 8 8))))))))
150 ;; use defaults, so no entries necessary
153 ;; use defaults; no entry needed
156 ;; default: group (3 2)
158 ((baseMoment . (1 . 8))
159 (beatStructure . (3 2))))
162 ;; default: group (3 3 2)
164 ((baseMoment . (1 . 8))
165 (beatStructure . (3 3 2))))
167 )) ; end of alist definition
170 ;;; Accessor and constructor functions
173 (define (get-setting my-symbol time-signature time-signature-settings)
174 "Get setting @code{my-symbol} for @code{time-signature} from
175 @code{time-signature-settings}."
176 (let ((my-time-signature-settings
177 (assoc-get time-signature time-signature-settings '())))
178 (assoc-get my-symbol my-time-signature-settings '())))
180 (define-public (make-setting base-fraction
184 (cons 'baseMoment base-fraction)
185 (cons 'beatStructure beat-structure)
186 (cons 'beamExceptions beam-exceptions)))
188 (define-public (base-fraction time-signature time-signature-settings)
189 "Get @code{baseMoment} fraction value for @var{time-signature} from
190 @var{time-signature-settings}."
191 (let ((return-value (get-setting 'baseMoment
193 time-signature-settings)))
194 (if (null? return-value)
195 (cons 1 (cdr time-signature))
198 (define-public (beat-structure base-fraction time-signature time-signature-settings)
199 "Get @code{beatStructure} value in @var{base-fraction} units
200 for @var{time-signature} from @var{time-signature-settings}."
201 (define (fraction-divide numerator denominator)
202 (/ (* (car numerator) (cdr denominator))
203 (* (cdr numerator) (car denominator))))
205 (let ((return-value (get-setting 'beatStructure
207 time-signature-settings)))
208 (if (null? return-value)
209 ;; calculate default beatStructure
210 (let* ((numerator (car time-signature))
211 (group-size (if (and (> numerator 3)
212 (zero? (remainder numerator 3)))
215 (beat-length (cons (* group-size (car base-fraction))
216 (cdr base-fraction)))
217 (beat-count (fraction-divide time-signature beat-length)))
218 (if (integer? beat-count)
219 (make-list beat-count group-size)
221 ;; use value obtained from time-signature-settings
224 (define-public (beam-exceptions time-signature time-signature-settings)
225 "Get @code{beamExceptions} value for @var{time-signature} from
226 @var{time-signature-settings}."
227 (get-setting 'beamExceptions time-signature time-signature-settings))
230 ;;; Functions for overriding time-signature settings
233 (define (override-property-setting context property setting value)
234 "Like the C++ code that executes \\override, but without type
237 (revert-property-setting context property setting)
238 (ly:context-set-property!
241 (cons (cons setting value) (ly:context-property context property)))))
243 (define (revert-property-setting context property setting)
244 "Like the C++ code that executes \revert, but without type
247 (define (entry-count alist entry-key)
248 "Count the number of entries in alist with a key of
252 ((equal? (caar alist) entry-key)
253 (+ 1 (entry-count (cdr alist) entry-key)))
254 (else (entry-count (cdr alist) entry-key))))
256 (define (revert-member alist entry-key)
257 "Return ALIST, with the first entry having a key of
258 ENTRY-KEY removed. ALIST is not modified, instead
259 a fresh copy of the list-head is made."
262 ((equal? (caar alist) entry-key) (cdr alist))
263 (else (cons (car alist)
264 (revert-member (cdr alist) entry-key)))))
266 ;; body of revert-property-setting
267 (let ((current-value (ly:context-property context property)))
268 (if (> (entry-count current-value setting) 1)
269 (ly:context-set-property!
272 (revert-member current-value setting)))))
274 (define-public (override-time-signature-setting time-signature setting)
275 "Override the time signature settings for the context in
276 @var{time-signature}, with the new setting alist @var{setting}."
279 (lambda (c) (override-property-setting
281 'timeSignatureSettings
286 (define-public (revert-time-signature-setting time-signature)
290 (revert-property-setting
292 'timeSignatureSettings
299 ;;;%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
300 ;;; Formatting of complex/compound time signatures
302 (define (insert-markups l m)
303 (let ((ll (reverse l)))
304 (let join-markups ((markups (list (car ll)))
305 (remaining (cdr ll)))
306 (if (pair? remaining)
307 (join-markups (cons (car remaining) (cons m markups)) (cdr remaining))
310 ;;; Use a centered-column inside a left-column, because the centered column
311 ;;; moves its reference point to the center, which the left-column undoes.
312 (define (format-time-fraction time-sig-fraction)
313 (let* ((revargs (reverse (map number->string time-sig-fraction)))
315 (nums (reverse (cdr revargs))))
316 (make-override-markup '(baseline-skip . 0)
318 (make-left-column-markup (list
319 (make-center-column-markup (list
320 (make-line-markup (insert-markups nums "+"))
323 (define (format-complex-compound-time time-sig)
324 (make-override-markup '(baseline-skip . 0)
327 (insert-markups (map format-time-fraction time-sig)
328 (make-vcenter-markup "+"))))))
330 (define-public (format-compound-time time-sig)
332 ((not (pair? time-sig)) (null-markup))
333 ((pair? (car time-sig)) (format-complex-compound-time time-sig))
334 (else (format-time-fraction time-sig))))
337 ;;;%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
338 ;;; Measure length calculation of (possibly complex) compound time signatures
340 (define (calculate-time-fraction time-sig-fraction)
341 (let* ((revargs (reverse time-sig-fraction))
343 (num (apply + (cdr revargs))))
344 (ly:make-moment num den)))
346 (define (calculate-complex-compound-time time-sig)
347 (let add-moment ((moment ZERO-MOMENT)
348 (remaining (map calculate-time-fraction time-sig)))
349 (if (pair? remaining)
350 (add-moment (ly:moment-add moment (car remaining)) (cdr remaining))
353 (define-public (calculate-compound-measure-length time-sig)
355 ((not (pair? time-sig)) (ly:make-moment 4 4))
356 ((pair? (car time-sig)) (calculate-complex-compound-time time-sig))
357 (else (calculate-time-fraction time-sig))))
360 ;;;%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
361 ;;; Base beat length: Use the smallest denominator from all fraction
363 (define (calculate-compound-base-beat-full time-sig)
364 (apply max (map last time-sig)))
366 (define-public (calculate-compound-base-beat time-sig)
369 ((not (pair? time-sig)) 4)
370 ((pair? (car time-sig)) (calculate-compound-base-beat-full time-sig))
371 (else (calculate-compound-base-beat-full (list time-sig))))))
374 ;;;%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
377 (define (normalize-fraction frac beat)
378 (let* ((thisbeat (car (reverse frac)))
379 (factor (/ beat thisbeat)))
380 (map (lambda (f) (* factor f)) frac)))
382 (define (beat-grouping-internal time-sig)
383 ;; Normalize to given beat, extract the beats and join them to one list
384 (let* ((beat (calculate-compound-base-beat-full time-sig))
385 (normalized (map (lambda (f) (normalize-fraction f beat)) time-sig))
386 (beats (map (lambda (f) (reverse (cdr (reverse f)))) normalized)))
387 (apply append beats)))
389 (define-public (calculate-compound-beat-grouping time-sig)
391 ((not (pair? time-sig)) '(2 . 2))
392 ((pair? (car time-sig)) (beat-grouping-internal time-sig))
393 (else (beat-grouping-internal (list time-sig)))))