bug report : lyluatex / latex embedding of score w/ introduction w/ incorrect bounding boxes

[Claire Meyer]

! Not the same bounding box problem as earlier this week (to the extent of
my knowledge) !

In recent lyluatex adventures of mine, I tried to reproduce a set of small
scores for piano and (one) voice. Each of them has an introduction (of 2 to
6 bars depending on the score) for the piano only, and the way it was
engraved in the original document is such that the introduction score is
separate from the theme score, but both are still on the "same line", so to
speak. To have a mental representation, imagine you have a piano score, and
instead of having an instrument name for the piano, you have another score.
Or imagine something very similar to the \incipit you have when
transcribing mensural music.

The thing is, \incipit automatically engraves music in mensural notation,
and I couldn't find a way to fully reverse to contemporary notation (in
particular the stems). So I wrote my introduction as markup, and put it as
the instrument name, and did the alignment as best I could with
indentation. I am fully aware this is a really ugly work around to achieve
my goal, but I don't know how to do it any other way, and it sort of
works...

... until it doesn't (sometimes, when embedding with latex / lyluatex). The
temporary pdf files  produced that are used to piece the final pdf document
are good and show all the musical content, but sometimes the temporary
.bbox text files containing the bounding boxes are incorrect. Those
incorrect bounding boxes have the correct size and orientation, but the
position is off, so that the final score on the final document goes out of
the page. And it's really a different issue than the one I sent a mail for
on Tuesday, because the temporary pdf files contain all the musical
content. It's really just the bounding box that is incorrect. Proof of it
is that the .bbox files are not regenerated with each compilation, so I
could just modify the two .bbox files corresponding to the two scores that
were skewed, and use a ruler placed on my screen until I was somewhat
satisfied that nobody would notice once the document is printed that the
alignment is sometimes off 2 mm.

Sorry for the backstory, but it seemed relevant, and I had to justify my
MWE to be 33 lines long, since I am unable to reproduce the bug without
doing an "introduction". (I really tried to make it the shortest.)

The alignment problem seem to appear when the indentation is too big:
- For the problematic scores, there was an indentation threshold after
which the thing goes oof (but below the threshold, that specific bug
doesn't appear; it's just that the introduction is not aligned, or even
doesn't fit in the page).
- For the non problematic scores, I didn't try to make them go oof.
- Some non problematic scores had bigger indentation without problem than
some problematically indented scores.

Note also that it's tied to the latex margins that I set, because if I have
bigger margins, the problem disappears.

Documents attached :
- MWE : test.ly (33 lines, 670 chars)  and latex.tex (7 lines, 237 chars)
- what it looks like compiled with lilypond : test.pdf
- what it looks like integrated via latex : latex.pdf

Configuration :
- lilypond v2.20.0
- texlive-full 20200626-1 w/ texlive-music 2019.52275-1
- OS : Manjaro KDE (arch-based)

Claire

test.ly
Description: Text Data

latex.pdf
Description: Adobe PDF document

latex.tex
Description: Text Data

test.pdf
Description: Adobe PDF document