Re: Workaround for issue 6307

[Jean Abou Samra]

Le 08/04/2022 à 21:54, Knute Snortum a écrit :
> Hi everyone.
>
> I am looking for a workaround for issue 6307 [1].  Under some
> circumstances, the stems of a beamed series of notes do not reach all
> the way down to the beam.  I've tried several different ways to
> correct this, but without success. Any help would be appreciated.
>
> %%%%%
> \version "2.22.2"
>
> \new Staff \with { \magnifyStaff #2/3 }
> {
>    \relative c'' {
>      \tuplet 3/2 {
>        %%% Below corrects beam thickness
>        \once \override Beam.beam-thickness = 0.25
>
>        %%% Below changes the stem lengths, but the beam
>        %%% still "shies away" from the bottom of the stem.
>        % \once \override Stem.details.beamed-lengths = #'(3 3 3)
>
>        %%% Below changes the beam position, but the stems
>        %%% still shy away from the beam.
>        % \once \override Beam.positions = #'(-1.5 . -2)
>        d8 c b
>      } \stopStaff \grace { s8 } s4
>    }
> }
> %%%%%
>
> [1] https://gitlab.com/lilypond/lilypond/-/issues/6307



Probably

\version "2.22.2"

\layout {
  \context {
    \Staff
    \consists
      #(lambda (context)
         (let ((beam #f)
               (staff-symbol #f))
           (make-engraver
            (acknowledgers
             ((beam-interface engraver grob source-engraver)
              (set! beam grob))
             ((staff-symbol-interface engraver grob source-engraver)
              (set! staff-symbol grob)))
            ((stop-translation-timestep engraver)
             (if (and beam staff-symbol)
                 (ly:grob-set-object! beam 'staff-symbol staff-symbol))
             (set! beam #f)))))
  }
}

\new Staff \with { \magnifyStaff #2/3 }
{
  \relative c'' {
    \tuplet 3/2 {
      d8 c b
    } \stopStaff \grace { s8 } s4
  }
}

Beams are created in a delayed manner, one 'time step' later than their
last note. Grobs are given staff symbols at the point they are
created. If you end the staff symbol right after the beam, this logic
gets defeated.

Jean