Fingering multiple voices above the stave

[Gerard Neil]

Hi everyone,

I'm having a bit of trouble fingering a chorale-like work for piano.
The upper staff has mostly two voices, and it looks best if I finger
them both above the stave. My first approach was to use \override
Fingering #'direction = #UP for the second voice, but then the
fingerings collide with note heads/stems in the first voice. (See
fingfing.ly/.png below)

I had a look on this list and the manual and I see that some people
are using \tweak #'extra-offset to do this sort of thing, but that
seems like way too much work, I have to manually position everything.

So I had the idea of attaching both fingerings to the topmost voice
(fingfing2) using something like "a'-\markup { \override
#'(baseline-skip . 1.5) \finger \column { 5 2 }}". That seems to take
care of the positioning quite nicely for me. I'm happy with this
solution, but it's still cumbersome to enter.

So I've got two questions:
1. Can someone help me write a macro/function to make this simpler? It
would be nice to be able to write something like a^\multiFinger { 2 3
}, for example. I'm sure this is possible, but I've spent a few hours
on it and I'm not really getting far.
2. Or, alternatively, has someone got a better solution?

Thanks,

Gerard

%---- fingfing.ly - override fingering direction in second voice -----

\include "english.ly"

rhOne = \relative c'' {
  \partial 4 d4 |
  cs^4 b8 cs a4 a'^5
}

rhTwo = \relative c'' {
  s4 a2^2 e4 cs'^2 |
}

\new Staff <<
  \key a \major \numericTimeSignature \time 4/4
  \clef treble
  \new Voice { \voiceOne \rhOne }
  \new Voice { \voiceTwo
    \override Fingering #'direction = #UP
    \rhTwo
  }
>>

%---- fingfing2.ly - attach fingering to topmost voice

\include "english.ly"

rhOne = \relative c'' {
  \partial 4 d4 |
  cs-\markup { \override #'(baseline-skip . 1.5) \finger \column { 4 2 }}
  b8 cs a4
  a'-\markup { \override #'(baseline-skip . 1.5) \finger \column { 5 2 }} |
}

rhTwo = \relative c'' {
  s4 a2 e4 cs' |
}

\new Staff <<
  \key a \major \numericTimeSignature \time 4/4
  \clef treble
  \new Voice { \voiceOne \rhOne }
  \new Voice { \voiceTwo \rhTwo }
>>

fingfing.png
Description: PNG image

fingfing2.png
Description: PNG image