Re: weird error with \repeat tremolo

[Aaron Hill]

On 2019-02-25 2:15 am, Thomas Morley wrote:
> Am Mo., 25. Feb. 2019 um 11:02 Uhr schrieb N. Andrew Walsh
> <address@hidden>:
> > Hi Aaron,
> >
> > On Mon, Feb 25, 2019 at 10:50 AM Aaron Hill <address@hidden> 
> > wrote:
> >    You could try manually lengthening
> > > the stem to see if it helps as a possible workaround.
> >
> >
> > I've gone all the way out to
> >
> >  \once \override Beam.positions = #'(-20 . -24)
> >
> > and still get the error, so I don't think tweaking stem length is 
> > going to help. Any idea what the error might be? Is there a bug 
> > report?
> >
> > Thanks for the help,
> >
> > A
> Some discussion here:
> https://lists.gnu.org/archive/html/bug-lilypond/2019-02/msg00000.html

I was so certain I had posted to the bug alias on this issue, but I 
cannot find it.  It was a pretty big write up too, testing lots of 
things.  But I am feeling like I must have dreamt it, since there's no 
trace.  :-/


> Here another minimal:
>
> \relative c'' {
>   %\voiceOne
>   d16. d32 \repeat tremolo 4 { b32 }
> }
>
> Looks like the error happens only if stems are pointing down, thus
> above compiles fine if voiceOne is uncommented.

The issue doesn't seem to be precisely stem direction.  You can trigger 
it with this:

%%%%
\version "2.19.82"
{ a32 8..:32 }
%%%%

If you change the note to g, then it works.  Lower notes result in a 
longer stem, which is why I had thought it might have something to do 
with stem length.

But then I found that beam-thickness can affect things too:

%%%%
\version "2.19.82"
{ \override Beam.beam-thickness = #0.488934 a32 8..:32 }
%%%%

This fails, but change the thickness to #0.488935 or higher and it 
works.

%%%%
\version "2.19.82"
{ \override StemTremolo.beam-thickness = #0.465801 a32 8..:32 }
%%%%

Again, this will fail, but *lower* the thickness to #0.465800 and it 
works.

-- Aaron Hill