Re: Getting back the dynamically coloured freboard dots on L2.20

[Thomas Morley]

Am Di., 3. Nov. 2020 um 22:45 Uhr schrieb Viktor Mastoridis
<viktor.mastoridis@gmail.com>:
>>
>>
>> A minimal would look like:
>>   \new FretBoards { \override FretBoard.color = #red a }
>> Changing dot-color  in 2.18. but not with 2.20.
>>
>> Investigating...
>>
>> Cheers,
>>   Harm
>
>
> Agreed.
> I'm sorry.
> It's the first time I'm posting on this kind/level of forum.
>

First bad commit is:

commit 5e3dc2111d63342ec00ecae8f3a1e38961349a1f
Author: Thomas Morley <thomasmorley65@gmail.com>
Date:   Mon May 26 23:44:30 2014 +0200

    Color and/or parenthesize single dots in fret-diagrams

    Issue 2752

    Makes it possible to color and/or parenthesize single dots in
    fret-diagram-verbose

    Introducing two properties for use in fret-diagram-details
     - fret-label-horizontal-offset
        affecting the fret-label-indication, like the existing
        `fret-label-vertical-offset'
     - paren-padding
        affecting the padding of the parenthesis

    Extending relevant reg-tests.

    Documenting it in NR, fretted-strings.itely

Well, so it's my own patch...
The patch introduces many nice features, among them coloring dots.
Alas, one cannot access the grob-color (if it is the return-value of a
procedure) in a reasonable way to use it as a fallback if dot-color is
unset. I have to think about it...

For now the following works:

%start of code
\version "2.20.0"

\header { title = "Guitar Chords" }

%Chords
\storePredefinedDiagram #default-fret-table \chordmode { a }
#guitar-tuning #"o;o;2-2;2-3;2-4;o;"
\storePredefinedDiagram #default-fret-table \chordmode { bes }
#guitar-tuning #"1-1-(;1-1;3-2;3-3;3-4;1-1-);"
\storePredefinedDiagram #default-fret-table \chordmode { c }
#guitar-tuning #"3-3;3-4;2-2;o;1-1;o;"

%Colour map
#(define color-mapping
  (list
    (cons (ly:make-pitch 0 0 NATURAL) 'red3)
    (cons (ly:make-pitch 0 5 NATURAL) 'blue3)
    (cons (ly:make-pitch 0 6 FLAT) 'magenta3)))

%Compare pitch and alteration (not octave).
#(define (pitch-equals? p1 p2)
  (and
    (= (ly:pitch-alteration p1) (ly:pitch-alteration p2))
    (= (ly:pitch-notename p1) (ly:pitch-notename p2))))

#(define (pitch-to-color pitch)
  (let ((color (assoc pitch color-mapping pitch-equals?)))
    (if color
        (cdr color))))

#(define (color-notehead grob)
  (x11-color
    (pitch-to-color
      (ly:event-property (event-cause grob) 'pitch))))

#(define (color-dot grob)
  (pitch-to-color
    (ly:event-property (event-cause grob) 'pitch)))

chordNames = \chordmode { a2 bes c }

\score {
  <<
    \new ChordNames \chordNames
    \new FretBoards
    {
      \override FretBoards.FretBoard #'size = #'2.0
      \override FretBoard #'(fret-diagram-details finger-code) = #'in-dot
      \override FretBoard #'(fret-diagram-details orientation) = #'portrait
      \override FretBoards.FretBoard #'color = #color-notehead
      \override FretBoards.FretBoard.before-line-breaking =
        #(lambda (grob)
          (ly:grob-set-nested-property! grob '(fret-diagram-details dot-color)
          (color-dot grob)))
      \chordNames
    }
  >>
}
%end of code

Cheers,
  Harm