Octava does not propagate to voices leading to incorrect rendering

[arshiacont]

Octava command does not seem to be effective across voices and repeating it will create more visual elements which is not intended.

Consider this score excerpt:

How would one notate the Octava in Guido? so that it takes effect on both voices?

Here are two failing attempts:

(1) Octava on first voice:

{[ \staff<1> 
  \clef<"g2"> \key<2> \meter<"C">  
 \stemsUp \slurBegin:1<curve="up">  b2/8
 empty/8  d3/8 empty/8 
 \oct<1> g/8 empty/8  b/8 empty/8 
  ]
 , 
[ \staff<1> 
  \stemsDown 
  \beamBegin:1  
  \tuplet<"3", dispNote="/16">( b2/24  d/24 g/24)
 \tuplet<"3", dispNote="/16">( b/24 g/24 d/24) \beamEnd:1   
 \beamBegin:1 \tuplet<"3", dispNote="/16">( d3/24 g2/24 b/24)
  \tuplet<"3", dispNote="/16">( d3/24 b2/24 g/24) \beamEnd:1 
 \beamBegin:1 \tuplet<"3", dispNote="/16">( g3/24  b2/24 d3/24)
 \tuplet<"3", dispNote="/16">( g/24 d/24 b2/24) \beamEnd:1  
 \beamBegin:1  \tuplet<"3", dispNote="/16">( b3/24  d/24 g/24)
 \tuplet<"3", dispNote="/16">( b/24 g/24 d/24)\beamEnd:1 
 ]
  }

(2) Octava on both voices:

{[ \staff<1> 
  \clef<"g2"> \key<2> \meter<"C">  
 \stemsUp \slurBegin:1<curve="up">  b2/8
 empty/8  d3/8 empty/8 
 \oct<1> g/8 empty/8  b/8 empty/8 
  ]
 , 

[ \staff<1> 
  \stemsDown 
  \beamBegin:1  
  \tuplet<"3", dispNote="/16">( b2/24  d/24 g/24)
 \tuplet<"3", dispNote="/16">( b/24 g/24 d/24) \beamEnd:1   
 \beamBegin:1 \tuplet<"3", dispNote="/16">( d3/24 g2/24 b/24)
  \tuplet<"3", dispNote="/16">( d3/24 b2/24 g/24) \beamEnd:1 
  \oct<1>
 \beamBegin:1 \tuplet<"3", dispNote="/16">( g3/24  b2/24 d3/24)
 \tuplet<"3", dispNote="/16">( g/24 d/24 b2/24) \beamEnd:1  
 \beamBegin:1  \tuplet<"3", dispNote="/16">( b3/24  d/24 g/24)
 \tuplet<"3", dispNote="/16">( b/24 g/24 d/24)\beamEnd:1 
 ]
  }

[dfober]

There is now a new hidden attribute for \octava.
I know this solution has limitations in your case since the octava sign you may choose to show may not have the right 'y position. I've started to investigate an automatic solution but again, it shows to be a bit tricky.

[zhwei8090]

I also encountered this problem
{[ \staff<1> \set<autoHideTiedAccidentals="on"> \auto<autoInstrPos="on"> \instr<"Piano"> \accol<id=0, range="1-2"> \barFormat<style= "system", range="1-2"> \bar<hidden="true"> (* meas. 1 *) \clef<"g2"> \key<0> \meter<"4/4", autoBarlines="off", autoMeasuresNum="system"> \oct<1> \stemsDown \beamBegin:1 c3/8 \stemsDown e/8 \stemsDown d/8 \stemsDown e/8 \beamEnd:1 \stemsDown \beamBegin:1 c/8 \stemsDown e/8 \stemsDown d/8 \stemsDown e/8 \beamEnd:1 \oct<0> \bar (* meas. 2 *) \oct<1> \stemsDown \beamBegin:1 c/8 \stemsDown e/8 \stemsDown d/8 \stemsDown e/8 \beamEnd:1 \stemsDown \beamBegin:1 c/8 \stemsDown e/8 \stemsDown d/8 \stemsDown e/8 \beamEnd:1 \oct<0> ] , [ \staff<1> \set<autoHideTiedAccidentals="on"> \barFormat<style= "system", range="1"> \bar<hidden="true"> (* meas. 1 *) \stemsUp \beamsOff c3/4 \noteFormat<dx=-38>( _/4) \noteFormat<dx=-58>( _/2) \bar (* meas. 2 *) \stemsUp \beamsOff g/4 \noteFormat<dx=-24>( _/4) \noteFormat<dx=-44>( _/2) ] , [ \staff<2> \set<autoHideTiedAccidentals="on"> \barFormat<style= "system", range="2"> \bar<hidden="true"> (* meas. 1 *) \staffFormat<distance=13> \clef<"f4"> \key<0> \meter<"4/4", autoBarlines="off", autoMeasuresNum="system"> \beamsOff c0/1 \bar (* meas. 2 *) \beamsOff c/1 ] }

[dfober]

Note that there is no conflict in your example: \oct is only on voice 1.
However I guess this is the kind of output you're expecting :
{
[ \staff<1>
\set<autoHideTiedAccidentals="on"> \auto<autoInstrPos="on"> \instr<"Piano">
\accol<id=0, range="1-2"> \barFormat<style= "system", range="1-2">
\bar<hidden="true">
(* meas. 1 ) \clef<"g2"> \key<0> \meter<"4/4", autoBarlines="off", autoMeasuresNum="system">
\oct<1, dy=5> \stemsDown \beamBegin:1 c3/8 \stemsDown e/8 \stemsDown d/8 \stemsDown e/8 \beamEnd:1
\stemsDown \beamBegin:1 c/8 \stemsDown e/8 \stemsDown d/8 \stemsDown e/8 \beamEnd:1
\oct<0> \bar
( meas. 2 ) \oct<1, dy=5> \stemsDown \beamBegin:1 c/8 \stemsDown e/8 \stemsDown d/8 \stemsDown e/8 \beamEnd:1
\stemsDown \beamBegin:1 c/8 \stemsDown e/8 \stemsDown d/8 \stemsDown e/8 \beamEnd:1
\oct<0>
] ,
[ \staff<1> \set<autoHideTiedAccidentals="on"> \barFormat<style= "system", range="1"> \bar<hidden="true">
( meas. 1 ) \oct<1, hidden="on"> \stemsUp \beamsOff c3/4 \restFormat<dy=-7>( _/4) \restFormat<dy=-4>( _/2) \bar
( meas. 2 ) \stemsUp \beamsOff g/4 \restFormat<dy=-7>( _/4) \restFormat<dy=-4>( _/2)
] ,
[ \staff<2> \set<autoHideTiedAccidentals="on"> \barFormat<style= "system", range="2"> \bar<hidden="true">
( meas. 1 ) \staffFormat<distance=13> \clef<"f4"> \key<0>
\meter<"4/4", autoBarlines="off", autoMeasuresNum="system"> \beamsOff c0/1 \bar
( meas. 2 *) \beamsOff c/1
]
}

It requires manual formatting (or a more clever conversion). It looks like there's already manual editing (otherwise I don't understand where the \noteFormat<dx=... comes from).
For the time being, that's the best the guido engine can do.

[arshiacont]

I believe the most serious Octava issue in the engine is #134 currently.

@zhwei8090 I guess that you are using LibMusicXML... I should cleanup and submit a PR that greatly improves Guido conversion... I'll try doing that ASAP.

[zhwei8090]

@dfober In fact, the score is like this, there will be conversion problems when there are multiple voices

[zhwei8090]

@arshiacont Yes, looking forward to your PR

[arshiacont]

@zhwei8090 better support for Octava is now available in xml2guido. It uses the new hidden feature added by @dfober . I wrestled alot with octave-shift conversion from musicXML to Guido and so far this is the best I have found but there are limitations such as how to choose which "octava" should be hidden!

I believe an ideal solution would be to have as many Octava on different voices and have the rendering engine somehow "merge" those octavas into the best one and finding the most suitable dy. I guess this is the path Dominique was taking. Let me know if you need help on this.

[zhwei8090]

@arshiacont I don't know how to describe this problem, it is certain to show a logical problem

[zhwei8090]

@arshiacont
Dropped an octave, not as expected

expected result：

testfile.xml.zip

[dfober]

looking at the gmn code, it see the following for the first voice:

 \oct<0> \stemsUp \beamBegin:1 \acc( d#2/16)

thus the engine shows what is written.
It looks like it's a conversion issue.

ps: it would be nice to reduce the code to the minimum that reproduces the problem, you would probably have discovered the same thing in this case

[arshiacont]

@zhwei8090 I have seen this before and it is an error that sometimes Finale introduces when encoding to MusicXML! If you look at the content of the MusicXML you'll see that it is actually closing early. If this is not the case, create a new ticket on LibMusicXML repo.

Keeping this ticket open as the multi-voice Octava is still an issue to be resolved (since using the current "hidden" parameter) does not really solve the problem. Ideally the engine should see all GROctavas and only draw the longest on the voice?!?

[zhwei8090]

@arshiacont @dfober It has been verified that there is indeed a problem when finale exports the xml, and re-editing the xml can solve it

[zhwei8090]

@arshiacont @dfober Have you encountered this problem? #144