Re: grob-object information

[address@hidden]

On 11 sept. 2012, at 17:48, Marc Hohl <address@hidden> wrote:

> Hello list,
> 
> for my work on the volta bracket inclusion for the new bar line interface,
> I need to know how the bars are ordered in (ly:grob-object grob 'bars).
> 
> Please see the attached file.
> 
> For the \musOne, I get a grob array with eight BarLine grobs
> (two for each staff) for the first volta bracket (and one for
> the second volta bracket, of course):
> 
> |------volta------|
> <BarLine> <BarLine>
> <BarLine> <BarLine>
> <BarLine> <BarLine>
> <BarLine> <BarLine>
> 
> 
> For \musTwo, I get a grob array consisting of eight BarLine grobs
> (because the bracket spans eight bars in a single line) and a second
> one for the second volta bracket.
> 
> |-------------------------------------volta-----------------------------------|
> <BarLine> <BarLine> <BarLine> <BarLine> <BarLine> <BarLine> <BarLine> 
> <BarLine>
> 
> 
> Is there any chance to get to know how the grobs are arranged?
> Or more formally: how can I get the 2D structure back from a 1D vector?
> 
> Thanks in advance,
> 
> Marc
> 
> <shortvoltatest.ly>_______________________________________________
> lilypond-devel mailing list
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You can use Grob::get_vertical_axis_group_index (you'd have to write a Scheme 
binding).  Or sort the list it based on ly:grob::vertical-less? (that binding 
is already written).

Cheers,
MS