changing size of \tempo marks

[Werner LEMBERG]

[2.17.26]

Folks,


it seems there isn't an easy possibility to change the size of \tempo
marks globally.  Have I missed something?  This code

  {
    \tempo "abc" c''1 |
    \override MetronomeMark.font-size = #20
    \override MetronomeMark.font-family = #'sans
    \tempo "abc" c''1 |
  }

has zero effect – inspite of the fact that `font-interface' is
explicitly mentioned in the list of supported interfaces of
`MetronomeMark' (in `lilypond-internals').  This smells like a bug...

Looking into metronome-engraver.cc, I see that the whole formatting
work is delegated to `metronomeMarkFormatter' (something which should
be mentioned in the documentation of `MetronomeMark'), which in turn
is by default bound to `format-metronome-markup'.  What about making
`format-metronome-markup' honor the unused `font-size' property of
`MetronomeMark' grobs?  Ditto for `font-shape' and friends.

Of course, I can simply provide a modified version of
`format-metronome-markup', but I consider this overkill if I just want
to change the font size...


    Werner