Re: Proposal: Changing tremolo beam gap implementation

[Torsten Hämmerle]

Thomas Morley-2 wrote
> see my code at
> https://lists.gnu.org/archive/html/lilypond-user/2020-04/msg00160.html
> 
> It's ofcourse a workaround, but usable, afaict.


Hi Harm,

It's good to have a workaround for the time being.
The reason why I haven't finished the "strange gap behaviour" issue 5868 yet
is because it is very much linked to the old issue 318 dealing with sloped
and centred whole-note tremolos, more or less just as you've implemented it
in your custom stencil fix.


By the way, as to your question (in the comments of your coding):


               ;; Beam
               ;; TODO where does this magic number, 0.81, comes from?

This magic number is nothing but the *standard beam translation* (i.e. the
vertical shift from beam to beam) and is a combination of standard beam
thickness (0.48) and standard line thickness (0.1), taking into account the
sit/straddle/hang beam placement rules.

For up to 3 beams, the standard beam translation basically is
0.5 * (2 + line-thickness - beam-thickness) = 0.5 * (2 + 0.1 - 0.48) =
*0.81*

Using this translation between beams will allow the upper beam to hang from
a stave line, the middle beam to straddle, and the lower beam to sit on a
stave line.


Further issues

I'm also trying to be prepared (code-wise) for the following (new) features,
partly already in the testing phase:

* slope damping (your slope is not damped, and I think even freely floating
beams in whole-note tremolos should not become too steep, they're no
glissandi.

* implement a proper sit/straddle/hang placement of freely floating beams. 
That seems to be more important than "exact" vertical centering between the
left and right notes/chords.

* keep away from ledger lines (just a little bit)

* (still to be done in my version) note-column shift as you did it,
especially needed if there are accidentals and dots.

* Alternative "Beam as if they were stemmed" approach as suggested by Elaine
Gould.

* Possibility of three or more note tremolos (never seen one in real life,
but, obviously, they do exist according to Gould)


Cheers,
Torsten





--
Sent from: http://lilypond.1069038.n5.nabble.com/User-f3.html