On 1/19/19, Davide Bonetti <address@hidden> wrote:
For the sake of the discussion, I copy there the code as it now is:
Greetings Davide and everybody,
although these chord-transform functions were only intended for
written voicings (i.e. not ChordNames), David K. had a brilliant idea:
by setting the 'octavation property for every transposed pitch, we can
print the intended voicing *without* causing the chord to loose its
name.
Problem: the version I tried to modify (see below) works nicely for
primary \dropNote and \raiseNote commands, but when they’re nested
(e.g. with \invertChords) it gives erratic results. There’s obviously
something I missed; could anybody give it a try and tell me where it’s
going off the rails?
%%%%%%%%%%%%%%%%%%%%%%%%%
\version "2.21.0"
#(define-public (move-chord-note n direction)
(_i "Transpose a note (numbered as @var{n}) by one octave in
@var{direction}.")
(lambda (music)
(let* ((elts (ly:music-property music 'elements))
(l (length elts))
;; if direction is up, count from the bottom note upward,
;; if direction is down, count from the top note downward.
(count-from (cond ((= direction UP) (- n 1))
((= direction DOWN) (- l n))))
;; Notes may not have been entered from bottom to top;
;; extract the pitches and put them in order.
(pitches (map (lambda (x) (ly:music-property x 'pitch))
(filter
(lambda (y)
(music-is-of-type? y 'note-event))
elts)))
(sorted (sort pitches ly:pitch<?)))
(if (and (music-is-of-type? music 'event-chord)
(not (zero? n)) (>= l n))
(begin
;; first apply the sorted pitches
;; to the actual notes.
(map (lambda (e p)
(ly:music-set-property! e 'pitch p))
elts sorted)
;; then transpose the note up or
;; down, depending on direction.
(let* ((note (list-ref elts count-from))
(oct (ly:music-property note 'octavation)))
(list-set! elts count-from
(ly:music-transpose note
(ly:make-pitch
(cond
((= direction UP) +1)
((= direction DOWN) -1))
0)))
(ly:music-set-property! note 'octavation
(+ (cond
((= direction UP) 1)
((= direction DOWN) -1))
(if (null? oct) 0 oct))))
))
music)))
dropNote =
#(define-music-function (parser location num music) (integer? ly:music?)
(_i "Drop a note of any chords in @var{music}, in @var{num}
position from above.")
(music-map (move-chord-note num down) music))
raiseNote =
#(define-music-function (parser location num music) (integer? ly:music?)
(_i "Raise a note of any chords in @var{music}, in @var{num}
position from below.")
(music-map (move-chord-note num up) music))
invertChords =
#(define-music-function (num music) (integer? ly:music?)
(_i "Invert any chords in @var{music} into their @var{num}-th position.
(Chord inversions may be directed downwards using negative integers.)")
(let loop ((num num) (music music))
(cond ((zero? num) music)
((negative? num) (loop (1+ num) (dropNote 1 music)))
(else (loop (1- num) (raiseNote 1 music))))))
ac =
\chordmode {
\dropNote 2 c:maj
\raiseNote 1 d:m7
\invertChords 2 e:m7
}
<<
\chords { \ac }
{
<>^\markup \sans "(should be: C△, Dm7 and Em7)"
\ac \bar "||"
}
%%%%%%%%%%%%%%%%%
Thanks!
V.