Am Do., 16. Jan. 2020 um 23:12 Uhr schrieb David Nalesnik
<david.nales...@gmail.com>:
>
> On Thu, Jan 16, 2020 at 3:42 PM David Nalesnik <david.nales...@gmail.com>
> wrote:
> >
> > Hi Robin,
> >
> > On Thu, Jan 16, 2020 at 1:02 PM Robin Bannister <r...@dabble.ch> wrote:
> > >
> > > Paolo Prete wrote:
> > >
> > > > This is *precious* info. Please, can you tell/confirm if
> > > >
> > > > 1) you are referring to \offset command ?
> > >
> > > No. That would be premature in this case.
> > >
> > >
> > > > 2) is it applicable as a replacement for "\offset Y-offset" for *every*
> > > > grob that support Y-offset ?
> > >
> > > Well, I have trouble following your trains of thought.
> > > I won't try to understand that question.
> > >
> > > And I'm puzzled why you focus directly on the property Y-offset.
> > >
> > >
> > > As regards the \offset command:
> > > The section 'Properties which may be offset' at
> > > http://lilypond.org/doc/v2.19/Documentation/notation/the-offset-command
> > > says the property must have a default setting in define-grobs.scm.
> > >
> > > OttavaBracket has the property outside-staff-padding because it supports
> > > the outside-staff-interface.
> > > http://lilypond.org/doc/v2.19/Documentation/internals/outside_002dstaff_002dinterface
> > > but define-grobs.scm doesn't set it.
> > >
> > > So you can't use \offset in this case until that is amended.
> >
> > This is an argument for adding these hidden default values directly to
> > define-grobs.scm.
> >
>
> Actually, you can set a default value from which \offset will work.
> It relies on the combination \override and \once \offset:
> \version "2.19.80"
>
> {
> \override Staff.OttavaBracket.outside-staff-padding = 0.46 % set me
> to default first!
> \ottava #1
> c''4 e'' d'' f''
> \ottava #0
> c''1
> \once \offset outside-staff-padding #2 Staff.OttavaBracket
> \ottava #1
> c''4 e'' d'' f''
> \ottava #0
> }
>
> Uh oh, now I've opened a can of worms :)
>
> David
>
And another one:
(To summarize;) It seems impossible to always get the actual used
values for properties with an unpure-pure-container. (Thus \offset has
problems in certain cases).
The actual used values are settled too late.
Though, (the other can of worms) we have the ´page-post-process´-hook.
See "Application Usage".
May lead to the code below.
Values are read after the _page_ is done, then used in a second run.
Thougn there's still some inaccuratesse, ~1/3-line-thickness, i.e.
~0.003, no idea where it comes from...
NB, It's nothing more then a proof-of-concept!
Tbh, I'd not try to make it really work ...
Anyway:
\version "2.19.83"
\paper { ragged-right = ##t }
test =
#(define-music-function (y) (number?)
(define (proc grob)
(let* ((orig (ly:grob-property grob 'stencil))
(sten
(grob-interpret-markup grob
#{
\markup
\with-dimensions-from \stencil #orig
\overlay {
\stencil #orig
\with-color #red
\translate #(cons 0 (- y))
\path #0.1
#`((moveto -1 ,y)
(lineto 1 ,y)
(moveto 0 ,y)
(lineto 0 0)
(moveto -1 0)
(lineto 1 0)
(moveto -0.5 1)
(lineto 0 0)
(lineto 0.5 1))
}
#})))
(ly:grob-set-property! grob 'stencil sten)))
#{ \override Staff.OttavaBracket.after-line-breaking = #proc #})
#(define (get-ottava-y-offs layout pages)
(let* ((lines (map (lambda (page) (ly:prob-property page 'lines)) pages))
(systems
(append-map
(lambda (line)
(append-map
(lambda (l)
(let ((system-grob (ly:prob-property l 'system-grob)))
(if (not (null? system-grob))
(list system-grob)
system-grob)))
line))
lines))
(system-elts
(map ly:grob-array->list
(map (lambda (sys) (ly:grob-object sys 'all-elements)) systems)))
(ottava-grobs
(map
(lambda (elt-list)
(filter
(lambda (elt)
(grob::has-interface elt 'ottava-bracket-interface))
elt-list))
system-elts))
(y-off-list
(map
(lambda (sub-list)
(map
(lambda (ottava-grob)
(let* ((staff-symbol
(ly:grob-object ottava-grob 'staff-symbol))
(sys (ly:grob-system ottava-grob))
(centered-staff-symbol-y-ext
(interval-center
(ly:grob-robust-relative-extent
staff-symbol sys Y)))
(centered-ottava-grob-y-ext
(interval-center
(ly:grob-robust-relative-extent
ottava-grob sys Y)))
(y-off
(+
(abs centered-staff-symbol-y-ext)
centered-ottava-grob-y-ext)))
y-off))
sub-list))
ottava-grobs)))
(ly:output-def-set-variable!
$defaultpaper
'ottava-y-off-list
(reverse (flatten-list y-off-list)))))
#(ly:output-def-set-variable!
$defaultpaper
'page-post-process
(lambda (layout pages) (get-ottava-y-offs layout pages)))
#(ly:book-process
#{
\book {
\score {
{
\ottava #1 c''''8 c'''' \ottava 0 c'''4
\ottava #1 a'''8 a''' \ottava 0 a''4
\ottava #1 a'''8( a''' \ottava 0 a''4)
\bar "" \break
\ottava #1 c''''8 c'''' \ottava 0 c'''4
\ottava #1 a'''8 a''' \ottava 0 a''4
\ottava #1 a'''8( a''' \ottava 0 a''4)
}
}
}
#}
$defaultpaper
$defaultlayout
(ly:parser-output-name))
#(let ((ottava-y-off-list
(ly:output-def-lookup $defaultpaper 'ottava-y-off-list)))
(ly:book-process
#{
\book {
\markup \wordwrap-string #"This is a proof of concept. Don't use it for
serious type-setting work before it is much more mature."
\score {
{
\test #(first ottava-y-off-list)
\ottava #1 c''''8 c'''' \ottava 0 c'''4
\test #(second ottava-y-off-list)
\ottava #1 a'''8 a''' \ottava 0 a''4
\test #(third ottava-y-off-list)
\ottava #1 a'''8( a''' \ottava 0 a''4)
\bar "" \break
\test #(fourth ottava-y-off-list)
\ottava #1 c''''8 c'''' \ottava 0 c'''4
\test #(fifth ottava-y-off-list)
\ottava #1 a'''8 a''' \ottava 0 a''4
\test #(sixth ottava-y-off-list)
\ottava #1 a'''8( a''' \ottava 0 a''4)
}
}
}
#}
$defaultpaper
$defaultlayout
(ly:parser-output-name)))
Cheers,
Harm
