>> Am I the only one who thinks users shouldn’t have to add
>> transparent letters with ascenders and descenders in order to have
>> a consistent line height?! Working with text should not require
>> such efforts…
>
> Unfortunately, LilyPond's idea of stencils is not prepared for doing
> that automatically: a stencil is basically a drawing expression + an
> X extent + an Y extent. The info on the lines of text that made
> this stencil, if it was made from text, is lost. [...]
Do you remember the discussion about `\strut` on the 'lilypond-devel'
list? I've come up with the following, which works nicely.
```
#(set-default-paper-size "a8landscape")
#(define-markup-command (strut layout props)
()
#:properties ((baseline-skip))
(let ((yext (cons (* -0.3 baseline-skip)
(* 0.7 baseline-skip))))
(ly:make-stencil
(ly:stencil-expr (make-transparent-box-stencil '(0 . 0.05) yext))
empty-interval
yext)))
\book {
\header { tagline = ##f }
\paper {
footnote-padding = -1\mm
footnote-separator-markup =
\markup \column {
\vspace #0.5
\fill-line { \override #'(span-factor . 1/2) \draw-hline }
\vspace #0.5
}
}
\markup "time-based footnotes"
\relative c'' {
r1 |
\footnote #'(-0.5 . -1)
\markup { \strut "Meter change." } Staff.TimeSignature
\time 3/4
\footnote #'(1 . -1)
\markup { \strut "Chord stem." } Stem
<c e g>4 q q
\footnote #'(-0.5 . 2)
\markup { \strut "Bar line." } Staff.BarLine
q q
\footnote #'(0.5 . -1)
\markup { \strut "Key change." } Staff.KeySignature
\key c \minor
q
}
}
```
There are some problems, though.
* In what context are footnote texts handled? I want to globally
adjust `baseline-skip` for my (redefined) `\strut` function, but I'm
not able to do it.
* `footnote-padding` is completely undocumented, as are the following
footnote parameters:
footnote-footer-padding
footnote-number-raise
footnote-stencil
number-footnote-table
footnote-numbering-function (at least there is a regtest)
* Too bad that `footnote-padding` is also applied between the footnote
separator and the first footnote, which necessitates a redefinition
of the footnote separator markup.
* If there were a context, I could apply Valentin's 'replace' trick:
```
\override TextScript.before-line-breaking =
#(lambda (grob)
(ly:grob-set-property!
grob 'text
(markup #:replace
`(("@" . ,#{ \markup{ \strut } #}))
(ly:grob-property grob 'text))))
```
[I'm aware that in this case `before-line-breaking` is probably not
correct, but...]
which would simplify the above footnote entries to
```
\footnote #'(-0.5 . -1) "@Meter change." Staff.TimeSignature
```
Werner
