Removing bar lines between piano staff and ossia and making space between consecutive ossias

[Arle Lommel]

Thanks to everyone for recent help. I've been truly impressed by how helpful people have been for my requests.

Now I have one more problem with the piano piece I am working on. I am using a pianoStaff, which works fine, except that I now have a portion with a bunch of ossia parts (almost one a measure) that occupy only about the span of an eighth note each. I have run into two issues that I cannot find addressed online anywhere, and I am hoping someone can help:

1. When adding an ossia to a piano staff the bar lines are automatically connected down from the ossia to the main piano staff. Normally not a problem, but for the piece I am working on I don't want them connecting. I find plenty of snippets about how to remove bar lines in the staff while leaving them on between staves, but nothing about the reverse. It isn't for lack of searching for a solution and trying out various things. So can anyone make a suggestion on how to achieve this?

2. In the first two instances where I call the ossia parts, there is one on the last half beat of a measure and a *separate* one on the first half beat of the next measure. Lilypond, quite logically, assumes that these should be stuck together (since there is no time between them) and under any other circumstance I would be happy for it to do so. But here it would be ideal if I could somehow put a little white space between them because I need to show that they are not a single continuous ossia but rather two separate optional performance variants.

So here is what I have versus what I want (showing both changes):

And here is a two measure example of the code (simplified from what is shown above to try to get closer to a tiny example:

\version "2.16.1"

staffPiano = \new PianoStaff {

\set PianoStaff.midiInstrument = #"acoustic grand"

\set PianoStaff.instrumentName = #"Piano"

\time 3/4

<<

\context Staff = "top" { 

\clef treble

\key b \major

\relative c' {

<<

{

\once \stemDown <e ais cis \tweak #'duration-log #1 fis> \arpeggio

}

\\

{

\tiny c''8\rest dis,8 dis4 dis4

}

\\

{ \skip 2 \skip 8

<<

\new Staff = Ossia \with {

alignAboveContext = #"top"

fontSize = #-2

\override StaffSymbol #'staff-space = #(magstep -2)

\remove "Time_signature_engraver"

\override Clef #'transparent = ##t

} {

\override Staff.KeySignature #'stencil = ##f

\key b \major

fis16 fis16 \ottava #0

}

>>

}

>>

|

<<

{

fis8[ fis8] fis8[ fis8] fis8 fis8]

}

\context Staff = Ossia {

\startStaff r8 dis8 \stopStaff

        }

>>

}

}

\context Staff = "bottom" {

\clef bass

\key b \major

\relative c {

fis,4 fis4 fis4 |

fis4 fis4 fis4 |

}

}

>>

}

\score {

<<

\staffPiano

>>

  \layout {

   \context {

     \PianoStaff

     \consists #Span_stem_engraver

     \consists "Span_arpeggio_engraver"

   }

  }

}

Any suggestions would be welcome.

-Arle Lommel