Re: strange octavation behaviour

[Thomas Morley]

2013/8/22 Simon Bailey <address@hidden>
>
> hi,
>
> consider the following snippet:
>
> --------
> \version "2.17.20"
> \new PianoStaff <<
>   \new Staff \relative c'''' {
>     \ottava #1 <g c e>4.\arpeggio b8 a4 f \ottava #0 |
>     R1
>     \ottava #1 <g c e>4.\arpeggio b8 a4 f \ottava #0 |
>   }
>   \new Staff \relative c'' {
>     \set PianoStaff.connectArpeggios = ##t
>     \ottava #1 <e g c>2\arpeggio \ottava #0 r2 |
>     R1
>     \ottava #1 <e g c>2\arpeggio r \ottava #0 |
>   }
> >>
> --------
>
> when compiled, it produces the output in the attached PNG.
>
> the first bar is the correct notation (i.e. the ottava bracket should stop 
> before the rest), but the ottava bracket is pushed into the arpeggio and ends 
> directly after the half note. in the third bar, the ottava bracket starts in 
> the correct place, but is somewhat too long. (actually i think it's too short 
> -- shouldn't the octavation spanner go as far as the note/rest _sounds_?).

Currently the OttavaBracket ends directly somewhere at the right of
the note where \ottava #0 is written.
IIRC, most (or all?) line-spanners do so. (One could think/argue about
some pros and contras.)
Some of them do have properties to tweak this behaviour a little bit:
'to-barline, 'end-on-accidental, 'shorten-pair. Perhaps I forgot
others.
The starting text of the OttavaBracket is moved to the right, because
the OttavaBracket isn't long enough to start the text on the note and
directly end the spanner.

>
> setting minimum-length just exacerbates the problem in the first bar by 
> shifting the "8va" further to the left…
>
> ideal behaviour:
> - ottava brackets should be vertically aligned
> - ottava brackets should be as long as the duration of the note[s]
>
> is there any way to magically create this behaviour?
>

One possibility would be to use
\override Staff.OttavaBracket #'shorten-pair = #'(0.0 . -0.6)
This is the default. Try out different numbers instead of -0.6

Another, using some grace-trickery, (this will disturb a midi, though):

\new PianoStaff <<
  \new Staff \relative c'''' {
    \ottava #1 <g c e>4.\arpeggio b8 a4 f \ottava #0 |
    R1
    \ottava #1 <g c e>4.\arpeggio b8 a4 f \ottava #0 |
  }
  \new Staff \relative c'' {
    \set PianoStaff.connectArpeggios = ##t
    \ottava #1 <e g c>2\arpeggio \grace \single\hideNotes e8 \ottava #0 r2 |
    R1
    \ottava #1 <e g c>2\arpeggio r \ottava #0 |
  }
>>

HTH,
  Harm