Re: baseline-skip affects font size???

[Thomas Morley]

2014-07-30 17:27 GMT+02:00 Richard Shann <address@hidden>:
> Dear List,
>
> I'm trying to write customized chord symbols, for better visibility when
> chord charts are displayed on smartphones. In this example I am trying
> to place an "m" above a white triangle after the chord name.
> I see that baseline-skip is affecting the size of the white triangle,
> which doesn't seem to be what's in the documentation.
> In fact with \override #'(baseline-skip . 0) I get no white triangle
> visible.
>
> \version "2.18.0"
> chExceptionMusic = {
>  <c' ees' g'>1 -\markup { \override #'(baseline-skip . 4) \column {  "m"   
> \tiny \triangle ##f }}
> }
> % Convert music to list and prepend to existing exceptions.
> chExceptions = #( append
>   ( sequential-music-to-chord-exceptions chExceptionMusic #t)
>   ignatzekExceptions)
>
> \score {
>
>  \context ChordNames  {
>     \set chordNameExceptions = #chExceptions
>     <c' ees' g'>
>     }
> }
>
> The example by the way, is fictitious, someone else will be providing me
> with real examples, but this is the sort of thing that will be needed,
> trading vertical for horizontal space.
>
> Any guidance on this?
>
> Richard Shann



Your observation is correct.
The triangle-markup-command uses baseline-skip to determine the size.

Looks very strange to me. I'd call it a bug worth fixing, though I've
no clue why it was put in this way at first place. Perhaps there was a
reason.

cc-ing bug-list

% c/p from define-markup-cpmmands.scm
#(define-markup-command (triangle layout props filled)
  (boolean?)
  #:category graphic
  #:properties ((thickness 0.1)
                (font-size 0)
                (baseline-skip 2))
  "
@cindex drawing triangles within text

A triangle, either filled or empty.

@lilypond[verbatim,quote]
\\markup {
  \\triangle ##t
  \\hspace #2
  \\triangle ##f
}
@end lilypond"
  (let ((ex (* (magstep font-size) 0.8 baseline-skip)))
%                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^
    (ly:make-stencil
     `(polygon '(0.0 0.0
                     ,ex 0.0
                     ,(* 0.5 ex)
                     ,(* 0.86 ex))
               ,thickness
               ,filled)
     (cons 0 ex)
     (cons 0 (* .86 ex)))))

\markup \override #'(baseline-skip . 0) \triangle ##f
\markup \override #'(baseline-skip . 1) \triangle ##f
\markup \override #'(baseline-skip . 2) \triangle ##f
\markup \override #'(baseline-skip . 3) \triangle ##f
\markup \override #'(baseline-skip . 4) \triangle ##f

Cheers,
  Harm