Re: Request for a cross-staff easy function

[Simon Albrecht]

Hi Paolo,

I reckon this isn’t easy to write, since you have to basically split the 
expressions up into individual elements and analyse them.

You can sometimes reduce effort by ‘cheating’ using simultaneous 
expressions within the voice like in this mockup: (if you explicitly 
instantiated the Voice using \new Voice, you can remove the \context Bottom)

\context Bottom <<
  \relative { c'16 e d f e g d f  c e h d a c h d  c1 }
  \repeat unfold 8 { s16 \change Staff = upper \voiceTwo s \change 
Staff = lower \voiceOne }
>>

Just as a general idea—real world applications are often too complicated 
for this to actually be faster to input. Also like so often, maintenance 
and code sharing get a lot easier with ‘low-tech’ coding and only using 
standard constructs, so the larger input effort is often worth it.

HTH, Simon

On 14.12.19 16:12, Paolo Prete wrote:
> Hi all,
>
> I think this function would be very useful for solving the limitations 
> of the current cross-staff interface:
>
> crossStaffExpr =  #(define-music-function (parser location 
> staffUpMusic  staffDownMusic beamPosition) (ly:music? ly:music? 
> number?) .....
>
> Example:
>
> \crossStaffExpr =  {  c '[   d'    g'   s    }
>                              {  s      s     f '   a']  } # 'BeamUp
>
> (the third parameter can be: BeamUp, BeamDown, or BeamBetween, where 
> BeamBetween places the beam between the two staves; BeamBetween can 
> only be used if there are no cross-staff chords)
>
> I ask you if there are any generous volunteers who want to implement 
> it, in case it requires not so many lines of code.
> in case it requires many lines of code, is it worth opening a ticket 
> in the dev ml?
>
> Thanks in advance
>
> P