-;;;; auto-beam.scm -- Auto-beam-engraver settings
+;;;; This file is part of LilyPond, the GNU music typesetter.
;;;;
-;;;; source file of the GNU LilyPond music typesetter
-;;;;
-;;;; (c) 2000--2005 Jan Nieuwenhuizen <janneke@gnu.org>
-
-;;; specify generic beam begin and end times
-
-;;; format:
-;;;
-;;; function shortest-duration-in-beam time-signature
-;;;
-;;; where
-;;;
-;;; function = begin or end
-;;; shortest-duration-in-beam = numerator denominator; e.g.: 1 16
-;;; time-signature = numerator denominator, e.g.: 4 4
-;;;
-;;; unspecified or wildcard entries for duration or time-signature
-;;; are given by * *
-
-;;; maybe do: '(end shortest-1 16 time-3 4) ?
-
-;;; in 3 2 time:
-;;; end beams each 1 2 note
-;;; end beams with 16th notes each 1 4 note
-;;; end beams with 32th notes each 1 8 note
-
-(define-public default-auto-beam-settings
- `(
- ((end * * 3 2) . ,(ly:make-moment 1 2))
- ((end 1 16 3 2) . ,(ly:make-moment 1 4))
- ((end 1 32 3 2) . ,(ly:make-moment 1 8))
-
- ((begin 1 8 3 4) . ,(ly:make-moment 1 4))
-
- ((end * * 3 4) . ,(ly:make-moment 3 4))
- ((begin 1 16 3 4) . ,(ly:make-moment 1 16))
- ((end 1 16 3 4) . ,(ly:make-moment 1 4))
- ;;((begin 1 32 3 4) . ,(ly:make-moment 1 8))
- ((end 1 32 3 4) . ,(ly:make-moment 1 8))
-
- ((begin 1 16 3 8) . ,(ly:make-moment 1 8))
- ((end * * 3 8) . ,(ly:make-moment 3 8))
-
- ;; in common time:
- ;; end beams each 1 2 note
- ;; end beams with 32th notes each 1 8 note
- ;; end beams with 1 8 triplets each 1 4 note
-
- ((end * * 4 4) . ,(ly:make-moment 1 2))
- ((end 1 12 4 4) . ,(ly:make-moment 1 4))
- ((end 1 16 4 4) . ,(ly:make-moment 1 4))
- ((end 1 32 4 4) . ,(ly:make-moment 1 8))
-
- ((end * * 2 4) . ,(ly:make-moment 1 4))
- ((end 1 12 2 4) . ,(ly:make-moment 1 4))
- ((end 1 16 2 4) . ,(ly:make-moment 1 4))
- ((end 1 32 2 4) . ,(ly:make-moment 1 8))
-
- ;; It seems that, because of a bug in the previous auto-beamer,
- ;; we had the effect of this setting x
- ;; ((end * * 2 8) . ,(ly:make-moment 2 8))
-
- ((end * * 4 8) . ,(ly:make-moment 1 4))
- ((end 1 16 4 8) . ,(ly:make-moment 1 4))
- ((end 1 32 4 8) . ,(ly:make-moment 1 8))
-
- ((end * * 4 16) . ,(ly:make-moment 1 8))
-
- ((end * * 6 8) . ,(ly:make-moment 3 8))
- ((end 1 16 6 8) . ,(ly:make-moment 3 8))
- ((end 1 32 6 8) . ,(ly:make-moment 1 8))
-
- ((end * * 9 8) . ,(ly:make-moment 3 8))
- ((end 1 16 9 8) . ,(ly:make-moment 3 8))
- ((end 1 32 9 8) . ,(ly:make-moment 1 8))
-
- ((end * * 12 8) . ,(ly:make-moment 3 8))
- ((end 1 16 12 8) . ,(ly:make-moment 3 8))
- ((end 1 32 12 8) . ,(ly:make-moment 1 8))
- ))
-
-
-(define (override-property-setting context context-prop setting value)
- "Like the C++ code that executes \\override, but without type
-checking. "
-
- (ly:context-set-property! context context-prop
- (cons (cons setting value)
- (ly:context-property context context-prop))))
-
-(define (revert-property-setting context setting)
- "Like the C++ code that executes \revert, but without type
-checking. "
-
- (define (revert-assoc alist key)
- "Return ALIST, with KEY removed. ALIST is not modified, instead
-a fresh copy of the list-head is made."
- (cond
- ((null? alist) '())
- ((equal? (caar alist) key) (cdr alist))
- (else (cons (car alist) (revert-assoc alist key)))))
-
- (ly:context-set-property!
- context context-prop
- (revert-assoc (ly:context-property context context-prop)
- setting)))
-
-(define-public (override-auto-beam-setting setting num den . rest)
- (ly:export
- (context-spec-music
- (make-apply-context (lambda (c)
- (override-property-setting
- c 'autoBeamSettings
- setting (ly:make-moment num den))))
- (if (and (pair? rest) (symbol? (car rest)))
- (car rest)
- 'Voice))))
-
-(define-public (score-override-auto-beam-setting setting num den)
- (override-auto-beam-setting setting num den 'Score))
+;;;; Copyright (C) 2000--2011 Jan Nieuwenhuizen <janneke@gnu.org>
+;;;;
+;;;; LilyPond is free software: you can redistribute it and/or modify
+;;;; it under the terms of the GNU General Public License as published by
+;;;; the Free Software Foundation, either version 3 of the License, or
+;;;; (at your option) any later version.
+;;;;
+;;;; LilyPond is distributed in the hope that it will be useful,
+;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+;;;; GNU General Public License for more details.
+;;;;
+;;;; You should have received a copy of the GNU General Public License
+;;;; along with LilyPond. If not, see <http://www.gnu.org/licenses/>.
+
+;; Determine whether an auto beam should be extended to the right
+;; of the current stem. We start anywhere except on the last note
+;; of a beat. We end according to the follwing rules, in order
+;; of decreasing priority:
+;;
+;; 1. end <type>
+;; 2. end <greater type>
+;; 3. if 1-2 not specified, end at beatStructure intervals
+;;
+;; Rationale:
+;;
+;; [user override]
+;; 1. override for specific duration type
+;; 2. overrides apply to shorter durations
+;;
+;; defined in scm/time-signature-settings.scm:
+;; 1. Default grouping for common time signatures
+
+(define-public (default-auto-beam-check context dir measure-pos test-beam)
+ (define (get name default)
+ (let ((value (ly:context-property context name)))
+ (if (not (null? value)) value default)))
+
+ (define (beaming<? a b)
+ (ly:moment<? (fraction->moment (car a))
+ (fraction->moment (car b))))
+
+ (define (ending-moments group-list start-beat base-moment)
+ (if (null? group-list)
+ '()
+ (let ((new-start (+ start-beat (car group-list))))
+ (cons (ly:moment-mul (ly:make-moment new-start 1) base-moment)
+ (ending-moments (cdr group-list) new-start base-moment)))))
+
+ (define (larger-setting test-beam sorted-alist)
+ (if (null? sorted-alist)
+ '()
+ (let* ((first-key (caar sorted-alist))
+ (first-moment (fraction->moment first-key)))
+ (if (moment<=? test-beam first-moment)
+ (car sorted-alist)
+ (larger-setting test-beam (cdr sorted-alist))))))
+
+ (define (beat-end? moment beat-structure)
+ (pair? (member moment beat-structure))) ;; member returns a list if found, not #t
+
+ ;; Start of actual auto-beam test routine
+ ;;
+ ;;
+ ;; Don't start auto beams on grace notes
+ (if (and (!= (ly:moment-grace-numerator (ly:context-now context)) 0)
+ (= dir START))
+ #f
+ (let* ((base-moment (get 'baseMoment (ly:make-moment 1 4)))
+ (measure-length (get 'measureLength (ly:make-moment 1 1)))
+ (time-signature-fraction
+ (get 'timeSignatureFraction '(4 . 4)))
+ (beat-structure (get 'beatStructure '(1 1 1 1)))
+ (beat-endings (ending-moments beat-structure 0 base-moment))
+ (exceptions (sort (assoc-get 'end
+ (get 'beamExceptions '())
+ '())
+ beaming<?))
+ (function (if (= dir START) 'begin 'end))
+ (type (moment->fraction test-beam))
+ (non-grace (ly:make-moment
+ (ly:moment-main-numerator measure-pos)
+ (ly:moment-main-denominator measure-pos)))
+ (pos (if (ly:moment<? non-grace ZERO-MOMENT)
+ (ly:moment-add measure-length non-grace)
+ non-grace))
+ (type-grouping (assoc-get type exceptions '()))
+ (default-rule (if (null? type-grouping)
+ (larger-setting test-beam exceptions)
+ '()))
+ (default-grouping (if (pair? default-rule)
+ (cdr default-rule)
+ '()))
+ (default-beat-length (if (pair? default-rule)
+ (car default-rule)
+ '()))
+ (exception-grouping (if (null? type-grouping)
+ default-grouping
+ type-grouping))
+ (grouping-moment (if (null? type-grouping)
+ (fraction->moment default-beat-length)
+ test-beam))
+ (exception-moments (ending-moments
+ exception-grouping 0 grouping-moment)))
+
+ (if (= dir START)
+ ;; Start rules
+ (or (not (equal? time-signature-fraction '(3 . 4))) ;; start anywher if not 3/4
+ (beat-end? pos beat-endings) ;; are we at start of beat?
+ (and (not (equal? test-beam base-moment)) ;; is beat split?
+ (not (beat-end? (ly:moment-add pos test-beam)
+ beat-endings)))) ;; will this note end the beat
+ ;; End rules
+ (or (= (ly:moment-main-numerator pos) 0) ;; end at measure beginning
+ (if (null? exception-grouping)
+ (beat-end? pos beat-endings) ;; no exception, so check beat ending
+ (member pos exception-moments))))))) ;; check exception rule
-(define-public (revert-auto-beam-setting setting . rest)
- (ly:export
- (context-spec-music
- (make-apply-context (lambda (c)
- (revert-property-setting
- c 'autoBeamSettings
- setting)))
- (if (and (pair? rest) (symbol? (car rest)))
- (car rest)
- 'Voice))))
projects / lilypond.git / blobdiff