Re: treble and bass clef simultaneously

[Werner LEMBERG]

>>>> for a solitary bass note I want to have a bass clef, not
>>>> affecting anything else in the staff.  How can I fix the attached
>>>> example?  I guess I need a music function that adjusts the
>>>> vertical note offset of the upper voice...
>>>
>>> Could you use an "ossia" that overlaps the staff?  [...]
>>
>> A very nice idea, thanks!  I admit that I would never have thought
>> of that.  Your example is almost perfect, except that I would like
>> to avoid the horizontal gap caused by bass clef.  What property
>> controls that?  I tried to modify some `Clef' properties given in
>> `define-grobs.scm', but I didn't get the desired effect.
> 
> Has the potential for overlapping ink, but try this:
> 
> %%%%
>   \override Clef.X-extent = #'(1.5 . 1.5)
> %%%%

Thanks, but this helps only partially.

I've now extended the example, see the attached stuff.  There are
still two problems.

* The overlay fails if used within a `PianoStaff' context.  This is a
  showstopper.

* The small bass clef is placed before a barline.

Ideas?


    Werner

\version "2.19.83"

% XXX hard-coded context `left'
fakeBassClef = #(define-music-function (treble bass)
                  (ly:music? ly:music?)
  #{
     << { \voiceOne #treble \oneVoice }
        \new Staff \with {
          \remove "Time_signature_engraver"
          alignAboveContext = #"left"
          \override VerticalAxisGroup.default-staff-staff-spacing =
            #'((basic-distance . 0)
               (minimum-distance . 0)
               (padding . -10)
               (stretchability . 0))
          \omit StaffSymbol
          \override Clef.font-size = #-2
          \override Clef.X-extent = #'(1.5 . 1.5)
          \override Clef.Y-offset =
            #(grob-transformer 'Y-offset (lambda (grob orig) (- orig 5)))
        } {
          \clef "bass" \voiceTwo #bass \oneVoice
        }
    >>
  #})


%%%%%

\new Staff = "left" \relative c'' {
  c8 g a g \fakeBassClef { <fis ais cis> g } { c,,,4 } a'''8 g |
  \fakeBassClef { <fis ais cis>8 g } { c,,,4 } a'''8 g c g a g |

  \break

  \fakeBassClef { <fis ais cis>8 g } { c,,,4 } a'''8 g c g a g |
  c8 g a g \fakeBassClef { <fis ais cis> g } { c,,,4 } a'''8 g |
}

%%%%%

\new PianoStaff {
  <<
    \new Staff = "right" \relative c'' {
      c1 | c1 | c1 | c1 |
    }
    \new Staff = "left" \relative c'' {
      c8 g a g \fakeBassClef { <fis ais cis> g } { c,,,4 } a'''8 g |
      \fakeBassClef { <fis ais cis>8 g } { c,,,4 } a'''8 g c g a g |

      \break

      \fakeBassClef { <fis ais cis>8 g } { c,,,4 } a'''8 g c g a g |
      c8 g a g \fakeBassClef { <fis ais cis> g } { c,,,4 } a'''8 g |
    }
  >>
}