Correct handling of serpent-style segno

[jobr42]

This is an issue that can be traced back to discussions on the musescore forum from 2014, and apart from some clumsy workarounds, nothing has changed as far as I'm aware.

The serpent sign exists in Musescore and can be found in the repeat pallet. It is implemented in the same way as an ordinary segno, which is not how serpents are usually used - they pretty much always sit right on the bar and essentially merge with a double bar line, instead of above the staff. This look is consistent between different publishers, composers and between single voices, condensed or expanded scores (see attached image). While the serpent might be uncommon in some, maybe even a lot of genres, it is very much alive and abundant in traditional polkas, marches and waltzes, including in the sheet music for some of the most popular works from some of the most popular publishers of those genres.

When there's a repeat right next to it, the serpent with its double bar line does switch next to it (placing a serpent on a repeat makes everything illegible after all), but it still essentially works like a combined bar line of serpent, double line and repeat. Workarounds like moving and sizing the serpent manually quickly fall apart when we're talking about multiple voices in the same song.

There are good reasons why you might prefer a serpent over an ordinary segno: As the segno sits above the stave, the distance between staves must be fairly large to accomodate it. As marching arrangements are often printed on smaller paper, a serpent saves space, meaning that the entire song can be printed at a larger scale. Or you might want multiple segnos in your song, so you differentiate by making one a serpent instead, avoiding any confusion. It also visibly stands out more, at least in my opinion.