Re: Tweaking glissando timing stems

[Leo Correia de Verdier]

Thanks a lot for your help!

Quite to my surprise I found the following snippet does work.

%%%%%%%%

\version "2.19.82"

#(define changebeam (lambda (grob)
                     (let* ((stem (ly:grob-object grob 'stem))
                            (beam (ly:grob-object stem 'beam)))
                       (ly:grob-set-property! beam 'positions '(-4 . 5))
                       )))

{\once \override NoteColumn.after-line-breaking = #changebeam
c8 d8 r2.}

%%%%%%%%

Unfortunately I couldn’t get changing the beams ’position property to work in 
the context of the larger function. Do you understand why?

Otherwise, the starting-point I see for recreating beams is drawing them from 
the stem’s beaming-property (querying other properties for thickness, spacing 
and slope damping). I think I could achieve that, but would like to know if 
someone sees a better option. 

On a sidetone from that: How does the (beam slope) damping factor affect the 
beam calculation? I can see and understand its effect, but wonder what the 
calculation behind it is.

Cheers
/Leo

> 17 okt. 2019 kl. 00:24 skrev Thomas Morley <address@hidden>:
> 
> Am Mo., 14. Okt. 2019 um 12:22 Uhr schrieb Leo Correia de Verdier
> <address@hidden>:
> 
>> When you write that "inner beams positions can’t be affected from 
>> Glissando.after-line-breaking", do you mean it’s impossible, that they would 
>> need to be recreated rather than repositioned or just that the actual code 
>> can’t handle them yet?
> 
> The code recreates Stems (and moves Script), but it can't _move_ Beams.
> It would likely be possible to completely recreate Beam.stencil,
> though this is inconveniant and would add a lot code...
> 
> Currently, this means my code sometimes returns ugly output for Beams,
> which will need to be corrected with an additional override for
> Beam.positions.
> 
> 
> Cheer,
>  Harm