Re: Adjustment to tablature output

[Christopher Webster]

> From:    Choan Gálvez
> Subject:         Re: Adjustment to tablature output
> Date:    Wed, 09 May 2012 01:23:26 +0200
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> On 5/8/12 10:48 , Christopher Webster wrote:
> Is there a recommended way of adjusting TabStaff output so that the
> note-heads (fret indications) appear _above_ rather than _on_ the lines
> representing the strings, please? This would make it more closely
> resemble English renaissance lute tablature, and I have a particular
> piece of transcription for which that is a desirable goal.
>
> I've got as far as guessing that assigning a non-standard procedure
> value as the tabStaffLineLayoutFunction property of
> Tab_note_heads_engraver would probably get me towards where I want to
> be, but alas I'm too stupid and/or too ill-informed to see how to write
> such a procedure.
>
> Shouldn't be that difficult. Check this thread: 
> <http://comments.gmane.org/gmane.comp.gnu.lilypond.general/57580>. By adjusting 
> the `TabNoteHead #'extra-offset` you can put the letters above the lines.
>
> Unfortunately, they won't align that nicely... but I can't help any further.
>
> Best.
> --
> Choan Gálvez
>
> Ukecosas. Los ukeleles que nos gustan, también para ti
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Many thanks for the advice and the link.

In the meantime, I searched this list's archives more carefully 
and found a solution which works perfectly.

Posted by Neil Puttock on Fri, 8 Apr 2011 20:40:16 +0100 and 
archived at 
http://lists.gnu.org/archive/html/lilypond-user/2011-04/msg00187.html 
:

> \override TabNoteHead #'Y-offset =
> #(lambda (grob)
>    (+ (/ (ly:staff-symbol-staff-space grob) 2)
>       (ly:staff-symbol-referencer::callback grob)))
> \override TabNoteHead #'whiteout = ##f

What wasn't immediately obvious to me was where to insert that 
fragment, but I got lucky at the first attempt by putting it 
inside the \with construct for my TabStaff :

  \new TabStaff
  \with
  {
    tablatureFormat = #fret-letter-tablature-format
    fretLabels = #luteFretLabels        % defined elsewhere by me
    stringTunings = #bandoraTuningSet   % defined elsewhere by me
    \override TabNoteHead #'Y-offset =
      #(lambda (grob)
        (+ (/ (ly:staff-symbol-staff-space grob) 2)
          (ly:staff-symbol-referencer::callback grob)))
    \override TabNoteHead #'whiteout = ##f
    \remove "Clef_engraver"
    \remove "Time_signature_engraver"
  }
  {
    % stuff ...
  }

I'd like to plead with the LilyPond developers to provide a more 
obvious and better documented way of achieving the same effect, 
but this presumably isn't the right place for that.

For the moment, I'm happy.  Many thanks.

            Christopher W.

Stockholm, Sweden.