Hi Heikki,
On Mon, Aug 17, 2015 at 7:47 AM, Heikki Junes <[email protected]>
wrote:
>
> 2015-08-17 15:34 GMT+03:00 David Kastrup <[email protected]>:
>>
>>
>> Key signature is a single grob. Your best bet probably is recoding the
>> print routine in lily/key-signature-interface.cc in Scheme (it appears
>> rather straightforward) and then add the desired color changes to it.
>> The alternative, namely calling the print routine and post-processing
>> the stencil is probably less robust against future changes in LilyPond.
>
>
> This recoding the print routine in scheme sound exactly the kind of
> solution I was looking at.
> Then that scheme code could be updated with a scheme script in the
> preamble of a .ly file,
> which would allow "\override Staff.KeySignature #'color =
> #color-keysignature".
>
> I would be very grateful, if somebody for whom this recoding is an easy job
> could take a catch on this idea.
>
In the attached file, I've recoded the print routine in Scheme, adding the
ability to color individual alterations based on their position relative to
the central line (= 0). Note that signatures for KeySignature and
KeyCancellation are handled independently.
I ran out of steam before I duplicated everything in the C++ function, but
hopefully this will give you what you need.
Best,
David
\version "2.19.23"
#(define (key-signature::special-print alt-color-list)
(lambda (grob)
(let* ((inter (/ (ly:staff-symbol-staff-space grob) 2.0))
(mol empty-stencil)
(c0s (ly:grob-property grob 'c0-position))
(is-cancellation? (grob::has-interface grob 'key-cancellation-interface))
(padding-pairs (ly:grob-property grob 'padding-pairs))
(fm (ly:grob-default-font grob))
(alist (ly:grob-property grob 'glyph-name-alist)))
(let loop ((s (ly:grob-property grob 'alteration-alist))
(stil mol)
(last-glyph-name #f))
(if (pair? s)
(let* ((alt (if is-cancellation? 0 (cdar s)))
(glyph-name (ly:assoc-get alt alist))
(acc (ly:font-get-glyph fm glyph-name))
(pos-list
(key-signature-interface::alteration-positions (car s) c0s grob))
(p (car pos-list))
(color (assoc-get p alt-color-list))
(acc
(if (color? color)
(stencil-with-color acc color)
acc))
(padding (ly:grob-property grob 'padding 0.0))
(handle (assoc (cons glyph-name last-glyph-name) padding-pairs))
(padding
(cond
((pair? handle) (cdr handle))
((and
(string=? glyph-name "accidentals.natural")
; ...
)
(+ padding 0.3))
(else padding))))
(loop (cdr s)
(ly:stencil-combine-at-edge
stil
X
LEFT
(ly:stencil-translate-axis acc (* p inter) Y)
padding)
glyph-name))
(ly:stencil-aligned-to stil X LEFT))))))
{
\override Staff.KeySignature.stencil =
#(key-signature::special-print `((4 . ,green) (-3 . ,red) (1 . ,blue)))
\override Staff.KeyCancellation.stencil =
#(key-signature::special-print `((-3 . ,magenta) (1 . ,cyan)))
\key ces \major
ces'1
\key a \major
a'1
\key g \major
g'1
}
_______________________________________________
lilypond-user mailing list
[email protected]
https://lists.gnu.org/mailman/listinfo/lilypond-user
