Re: markup-command boxing the real printed ink?

[Thomas Morley]

Am Di., 20. Apr. 2021 um 16:39 Uhr schrieb Thomas Morley
<thomasmorley65@gmail.com>:
>
> Am Di., 20. Apr. 2021 um 15:45 Uhr schrieb David Kastrup <dak@gnu.org>:
> >
> > Valentin Petzel <valentin@petzel.at> writes:
> >
> > > Hello Harm,
> > >
> > > This is probably quite hard to do. Basically the problem here is that
> > > Lilypond does not in fact know the actual extent of the stencil. So to
> > > get that you’d somehow need to draw the stencil. So eighter you’d need
> > > to implement a custom drawing routine for "drawing" stencils within
> > > Lilypond, or you could try to do a function that takes a stencil,
> > > creates a new book containing that stencil, you’d then postprocess
> > > that file with a script that determines the actual extent and writes
> > > it into an auxiliary file, which is then included and gives the first
> > > function a value for overriding the extent.
> >
> > You do realise that LilyPond processes outlines?  It would seem that
> > what Harm is asking for is recalculating markup bounding box dimensions
> > from its outline.  That would seem to require some C++ code I think, but
> > not at the low level you suggest.  More like adding something similar to
> > "with-outline" support to lily/stencil-integral.cc and
> > lily/stencil-interpret.cc .
> >
> > --
> > David Kastrup
>
> We have the markup-command \with-outline.
> Alas, it looks not like what I would need and tbh, I've no clue how to
> use it, no example there.
>
> $ git grep "with-outline"
> lily/stencil-integral.cc:  else if (scm_is_eq (head, ly_symbol2scm
> ("with-outline")))
> lily/stencil-interpret.cc:      else if (scm_is_eq (head,
> ly_symbol2scm ("with-outline")))
> lily/stencil.cc:                       scm_list_3 (ly_symbol2scm
> ("with-outline"),
> scm/define-markup-commands.scm:(define-markup-command (with-outline
> layout props outline arg)
> scm/define-stencil-commands.scm:    with-outline
> scm/stencil.scm:         ((eq? head 'with-outline) (interpret (cadr expr)))
>
> shows no doc/code-example as well.
>
> Anyway:
>
> I stumbled across the problem while looking at
> https://lists.gnu.org/archive/html/lilypond-user/2021-03/msg00187.html
> There's the complain note-by-number note working nicely with the 
> Scorlatti-font.
> For testing, I took the font from https://github.com/OpenLilyPondFonts.
>
> Further investigation showed Scorlatti-note-heads exceed the bounding
> box. With this in mind I asked here.

Screw below, I was viewing artifacts of my insufficient pdf-viewer.
Which leads to the question whether the method how it works in
notemode could be made accessible via scheme.

> Meanwhile I noticed that this holds for use in notemode as well (the
> up-Stem is always a little off).
> Same for lilyjazz from there. gonville is fine. Didn't test the others
>
> This leads to the conclusion that this scorlatti-font is unusable.
>
> Not sure whether there are free variants of these font out there.
>
> Thanks,
>   Harm