ossia with signatures where needed

[James Harkins]

Is it possible to create an ossia staff context where clefs and time signatures 
are displayed only when the staff is visible?

I'm following the model of the 3rd example under "Ossia staves" in the notation 
reference -- creating a staff named "ossia" and then using \context 
Staff="ossia" { \startStaff ... \stopStaff } where it should be visible. This 
is fine as long as I...

      \remove "Time_signature_engraver"
      \remove "Key_engraver"
      \override Clef #'transparent = ##t

But then, clefs, time signatures and keys will never be displayed. I have an 
ossia that crosses a couple of time signatures, and it looks funny that the 
time signatures are absent. But if I remove those lines from the ossia staff's 
\with block then I get a free-floating clef, time signature and key signature 
-- without staff lines -- above the "real" staff.

I'm sure it must be possible -- it just eludes me in the documentation tonight.

Thanks,
James


%%% For reference, the file layout goes something like this (omitting some fine 
print):

\outline {
        ... meter changes and spacer rests...
}

\score {
  \new StaffGroup \with {
    \override SpanBar #'glyph-name = #":"
  }
  <<
    \set StaffGroup.systemStartDelimiter = #'SystemStartBar
    \new Staff = "ossia" \with {
      \remove "Time_signature_engraver"
      \remove "Key_engraver"
      \override Clef #'transparent = ##t
      fontSize = #-3
      \override StaffSymbol #'staff-space = #(magstep -3)
      \override StaffSymbol #'thickness = #(magstep -3)
    } {
      \stopStaff \outline
    }
    \new Staff <<
      \outline
      {
        ... whole bunch of notes...
        <<
          {
                ... notes, ossia goes above this...
          }
          \context Staff="ossia" {
            \startStaff
            \relative c'' {
              d8^"accented note rhythm" b8 r16 [ d8 b16 ] r8 d \noBeam b d
              r8 b d [ r16 b ] r16 d16 r8
              b8. d b d b8 r8
            }
            \stopStaff
          }
        >>
        ... a lot more notes...
      }
    >>
  >>
  \layout {
    \context { \RemoveEmptyStaffContext }
    \context {
      \Score
      \remove "System_start_delimiter_engraver"
    }
  }
}


--
James Harkins /// dewdrop world
address@hidden
http://www.dewdrop-world.net

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Sing me a song no poet has yet chanted,
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