1 ;;;; This file is part of LilyPond, the GNU music typesetter.
3 ;;;; Copyright (C) 2004--2012 Han-Wen Nienhuys <hanwen@xs4all.nl>
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 ; for define-safe-public when byte-compiling using Guile V2
19 (use-modules (scm safe-utility-defs))
21 (define-public (construct-chord-elements root duration modifications)
22 "Build a chord on root using modifiers in @var{modifications}.
23 @code{NoteEvents} have duration @var{duration}.
25 Notes: Natural 11 is left from chord if not explicitly specified.
27 Entry point for the parser."
28 (let* ((flat-mods (flatten-list modifications))
29 (base-chord (stack-thirds (ly:make-pitch 0 4 0) the-canonical-chord))
37 (define (interpret-inversion chord mods)
38 "Read /FOO part. Side effect: INVERSION is set."
39 (if (and (> (length mods) 1) (eq? (car mods) 'chord-slash))
41 (set! inversion (cadr mods))
42 (set! mods (cddr mods))))
43 (interpret-bass chord mods))
45 (define (interpret-bass chord mods)
46 "Read /+FOO part. Side effect: BASS is set."
47 (if (and (> (length mods) 1) (eq? (car mods) 'chord-bass))
49 (set! bass (cadr mods))
50 (set! mods (cddr mods))))
52 (ly:warning (_ "Spurious garbage following chord: ~A") mods))
55 (define (interpret-removals chord mods)
56 (define (inner-interpret chord mods)
57 (if (and (pair? mods) (ly:pitch? (car mods)))
58 (inner-interpret (remove-step (+ 1 (ly:pitch-steps (car mods))) chord)
60 (interpret-inversion chord mods)))
61 (if (and (pair? mods) (eq? (car mods) 'chord-caret))
62 (inner-interpret chord (cdr mods))
63 (interpret-inversion chord mods)))
65 (define (interpret-additions chord mods)
66 "Interpret additions. TODO: should restrict modifier use?"
67 (cond ((null? mods) chord)
68 ((ly:pitch? (car mods))
69 (if (= (pitch-step (car mods)) 11)
70 (set! explicit-11 #t))
71 (interpret-additions (cons (car mods) (remove-step (pitch-step (car mods)) chord))
73 ((procedure? (car mods))
74 (interpret-additions ((car mods) chord)
76 (else (interpret-removals chord mods))))
78 (define (pitch-octavated-strictly-below p root)
79 "return P, but octavated, so it is below ROOT"
80 (ly:make-pitch (+ (ly:pitch-octave root)
81 (if (> (ly:pitch-notename root)
82 (ly:pitch-notename p))
85 (ly:pitch-alteration p)))
87 (define (process-inversion complete-chord)
88 "Take out inversion from COMPLETE-CHORD, and put it at the bottom.
89 Return (INVERSION . REST-OF-CHORD).
91 Side effect: put original pitch in INVERSION.
92 If INVERSION is not in COMPLETE-CHORD, it will be set as a BASS, overriding
96 (let* ((root (car complete-chord))
98 (and (= (ly:pitch-notename y)
99 (ly:pitch-notename inversion))
100 (= (ly:pitch-alteration y)
101 (ly:pitch-alteration inversion)))))
102 (rest-of-chord (remove inv? complete-chord))
103 (inversion-candidates (filter inv? complete-chord))
104 (down-inversion (pitch-octavated-strictly-below inversion root)))
105 (if (pair? inversion-candidates)
106 (set! inversion (car inversion-candidates))
108 (set! bass inversion)
109 (set! inversion #f)))
111 (cons down-inversion rest-of-chord)
113 ;; root is always one octave too low.
114 ;; something weird happens when this is removed,
115 ;; every other chord is octavated. --hwn... hmmm.
116 (set! root (ly:pitch-transpose root (ly:make-pitch 1 0 0)))
117 ;; skip the leading : , we need some of the stuff following it.
118 (if (pair? flat-mods)
119 (if (eq? (car flat-mods) 'chord-colon)
120 (set! flat-mods (cdr flat-mods))
121 (set! start-additions #f)))
123 (if (and (pair? flat-mods) (procedure? (car flat-mods)))
125 (set! lead-mod (car flat-mods))
126 (set! flat-mods (cdr flat-mods))))
127 ;; extract first number if present, and build pitch list.
128 (if (and (pair? flat-mods)
129 (ly:pitch? (car flat-mods))
130 (not (eq? lead-mod sus-modifier)))
132 (if (= (pitch-step (car flat-mods)) 11)
133 (set! explicit-11 #t))
135 (stack-thirds (car flat-mods) the-canonical-chord))
136 (set! flat-mods (cdr flat-mods))))
138 (if (procedure? lead-mod)
139 (set! base-chord (lead-mod base-chord)))
142 (interpret-additions base-chord flat-mods)
143 (interpret-removals base-chord flat-mods)))
144 (set! complete-chord (sort complete-chord ly:pitch<?))
145 ;; If natural 11 + natural 3 is present, but not given explicitly,
147 (if (and (not explicit-11)
148 (get-step 11 complete-chord)
149 (get-step 3 complete-chord)
150 (= 0 (ly:pitch-alteration (get-step 11 complete-chord)))
151 (= 0 (ly:pitch-alteration (get-step 3 complete-chord))))
152 (set! complete-chord (remove-step 11 complete-chord)))
153 ;; must do before processing inversion/bass, since they are
154 ;; not relative to the root.
155 (set! complete-chord (map (lambda (x) (ly:pitch-transpose x root))
158 (set! complete-chord (process-inversion complete-chord)))
160 (set! bass (pitch-octavated-strictly-below bass root)))
163 (write-me "\n*******\n" flat-mods)
164 (write-me "root: " root)
165 (write-me "base chord: " base-chord)
166 (write-me "complete chord: " complete-chord)
167 (write-me "inversion: " inversion)
168 (write-me "bass: " bass)))
170 (make-chord-elements (cdr complete-chord) bass duration (car complete-chord)
172 (make-chord-elements complete-chord bass duration #f #f))))
175 (define (make-chord-elements pitches bass duration inversion original-inv-pitch)
176 "Make EventChord with notes corresponding to PITCHES, BASS and
177 DURATION, and INVERSION."
178 (define (make-note-ev pitch)
179 (make-music 'NoteEvent
182 (let ((nots (map make-note-ev pitches))
183 (bass-note (if bass (make-note-ev bass) #f))
184 (inv-note (if inversion (make-note-ev inversion) #f)))
187 (set! (ly:music-property bass-note 'bass) #t)
188 (set! nots (cons bass-note nots))))
191 (set! (ly:music-property inv-note 'inversion) #t)
192 (set! (ly:music-property inv-note 'octavation)
193 (- (ly:pitch-octave inversion)
194 (ly:pitch-octave original-inv-pitch)))
195 (set! nots (cons inv-note nots))))
199 ; chord modifiers change the pitch list.
201 (define (aug-modifier pitches)
202 (set! pitches (replace-step (ly:make-pitch 0 4 SHARP) pitches))
203 (replace-step (ly:make-pitch 0 2 0) pitches))
205 (define (minor-modifier pitches)
206 (replace-step (ly:make-pitch 0 2 FLAT) pitches))
208 (define (maj7-modifier pitches)
209 (set! pitches (remove-step 7 pitches))
210 (cons (ly:make-pitch 0 6 0) pitches))
212 (define (dim-modifier pitches)
213 (set! pitches (replace-step (ly:make-pitch 0 2 FLAT) pitches))
214 (set! pitches (replace-step (ly:make-pitch 0 4 FLAT) pitches))
215 (set! pitches (replace-step (ly:make-pitch 0 6 DOUBLE-FLAT) pitches))
218 (define (sus-modifier pitches)
219 (remove-step (pitch-step (ly:make-pitch 0 2 0)) pitches))
221 (define-safe-public default-chord-modifier-list
222 `((m . ,minor-modifier)
223 (min . ,minor-modifier)
224 (aug . , aug-modifier)
225 (dim . , dim-modifier)
226 (maj . , maj7-modifier)
227 (sus . , sus-modifier)))
229 ;; canonical 13 chord.
230 (define the-canonical-chord
236 (ly:make-pitch 1 (- n 8) (nca n))
237 (ly:make-pitch 0 (- n 1) (nca n))))
240 (define (stack-thirds upper-step base)
241 "Stack thirds listed in BASE until we reach UPPER-STEP. Add
242 UPPER-STEP separately."
243 (cond ((null? base) '())
244 ((> (ly:pitch-steps upper-step) (ly:pitch-steps (car base)))
245 (cons (car base) (stack-thirds upper-step (cdr base))))
246 ((<= (ly:pitch-steps upper-step) (ly:pitch-steps (car base)))