-;;;
-;;; auto-beam.scm -- Auto-beam-engraver settings
-;;;
-;;; source file of the GNU LilyPond music typesetter
-;;;
-;;; (c) 2000--2001 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; eg: 1 16
-;;; time-signature = numerator denominator, eg: 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 auto-beam-settings
- `(
- ((end * * 3 2) . ,(make-moment 1 2))
- ((end 1 16 3 2) . ,(make-moment 1 4))
- ((end 1 32 3 2) . ,(make-moment 1 8))
-
- ((begin 1 8 3 4) . ,(make-moment 1 4))
-
- ((end * * 3 4) . ,(make-moment 3 4))
- ((begin 1 16 3 4) . ,(make-moment 1 16))
- ((end 1 16 3 4) . ,(make-moment 1 4))
- ;;((begin 1 32 3 4) . ,(make-moment 1 8))
- ((end 1 32 3 4) . ,(make-moment 1 8))
-
- ((begin 1 16 3 8) . ,(make-moment 1 8))
- ((end * * 3 8) . ,(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) . ,(make-moment 1 2))
- ((end 1 12 4 4) . ,(make-moment 1 4))
- ((end 1 16 4 4) . ,(make-moment 1 4))
- ((end 1 32 4 4) . ,(make-moment 1 8))
-
- ((end * * 2 4) . ,(make-moment 1 4))
- ((end 1 12 2 4) . ,(make-moment 1 4))
- ((end 1 16 2 4) . ,(make-moment 1 4))
- ((end 1 32 2 4) . ,(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) . ,(make-moment 2 8))
-
- ((end * * 4 8) . ,(make-moment 1 4))
- ((end 1 16 4 8) . ,(make-moment 1 4))
- ((end 1 32 4 8) . ,(make-moment 1 8))
-
- ((end * * 4 16) . ,(make-moment 1 8))
-
- ((end * * 6 8) . ,(make-moment 3 8))
- ((end 1 16 6 8) . ,(make-moment 3 8))
- ((end 1 32 6 8) . ,(make-moment 1 8))
-
- ((end * * 9 8) . ,(make-moment 3 8))
- ((end 1 16 9 8) . ,(make-moment 3 8))
- ((end 1 32 9 8) . ,(make-moment 1 8))
-
- ((end * * 12 8) . ,(make-moment 3 8))
- ((end 1 16 12 8) . ,(make-moment 3 8))
- ((end 1 32 12 8) . ,(make-moment 1 8))
- ))
+;;;; This file is part of LilyPond, the GNU music typesetter.
+;;;;
+;;;; Copyright (C) 2000--2009 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 end moment for auto beaming (or begin moment, but mostly
+;; 0== anywhere). We only consider the current time signature.
+;; In order of decreasing priority:
+;;
+;; 1. end <type>
+;; 2. end *
+;; 3. if 1-2 not specified, begin anywhere, end at beatLength intervals
+;;
+;; Rationale:
+;;
+;; [user override]
+;; 1. override for specific duration type
+;; 2. override for all duration types in a time signature.
+;;
+;; defined in scm/beam-settings.scm:
+;; 1. Default grouping for common time signatures
+;; 2. exceptions for specific time signature, for specific duration type
+
+
+(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 (ending-moments group-list start-beat beat-length)
+ (if (null? group-list)
+ '()
+ (let ((new-start (+ start-beat (car group-list))))
+ (cons (ly:moment-mul (ly:make-moment new-start 1) beat-length)
+ (ending-moments (cdr group-list) new-start beat-length)))))
+
+ ;; 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
+ (if (= dir START)
+ ;; start anywhere is currently implemented
+ #t
+ (let* ((beat-length (get 'beatLength (ly:make-moment 1 4)))
+ (measure-length (get 'measureLength (ly:make-moment 1 1)))
+ (time-signature-fraction
+ (get 'timeSignatureFraction '(4 . 4)))
+ (settings (get 'beamSettings '()))
+ (function (if (= dir START) 'begin 'end))
+ (type (cons (ly:moment-main-numerator test-beam)
+ (ly:moment-main-denominator test-beam)))
+ (pos (if (>= (ly:moment-main-numerator measure-pos) 0)
+ measure-pos
+ (ly:moment-add measure-length measure-pos)))
+ (type-grouping (ly:beam-grouping
+ settings
+ time-signature-fraction
+ function
+ type))
+ (default-grouping (ly:beam-grouping
+ settings
+ time-signature-fraction
+ function
+ '*))
+ (beat-grouping (if (null? type-grouping)
+ default-grouping
+ type-grouping))
+ (grouping-moment (if (null? type-grouping)
+ beat-length
+ test-beam))
+ (grouping-moments (ending-moments
+ beat-grouping 0 grouping-moment)))
+ (if (null? beat-grouping)
+ ;; no rule applies, so end at beatLength
+ (= (ly:moment-main-denominator
+ (ly:moment-div pos beat-length)) 1)
+ ;; otherwise, end at beginning of measure or
+ ;; at specified moment
+ (or
+ ;; start/end at beginning of measure
+ (= (ly:moment-main-numerator pos) 0)
+ ;; end if measure-pos matches a specified ending moment
+ (member pos grouping-moments)))))))
projects / lilypond.git / blobdiff