Fusion Enhancements

[rpspringuel]

Graduale Novum, in the offertory Recordare on p. 340 of the first volume, namely the first four notes, a torculus resupinus terminating with a virga:

Sandhofe's 2002 Nocturnale Romanum, page [126] in the Common for Virgins and non Virgins, Responsory 6 for Virgins, Offerentur Regi, sort of a porrectus with a fifth note stacked on top of the fourth (which should be a quilisma), at the end of the syllable Re in Regi:

As best I can tell, the current rules for fusion prohibit both of these combinations (the latter is explicitly spelled out in the documentation, but the there's no mention of a virga as a primitive element in the fusion rules). @henryso Can we modify the fusion rules to make these possible?

Reference mailing list thread: https://groups.google.com/g/gregorio-users/c/2NpiJsjEQnU/m/Ho_JZCxIAgAJ?utm_medium=email&utm_source=footer&pli=1

[henryso]

It's possible. It would require virga endings as well as a "quilisma pes" endings to be drawn and added to the glyph set along with the changes in the fusion code.

[rpspringuel]

Don't those glyphs already exist outside of fusion?

[henryso]

Not the ones with little nubs to connect to the lines of the previous glyph.

[henryso]

The quilisma-pes will end up being 5 glyphs given the ambitus.

[rpspringuel]

Where are we in terms of available glyph space?

[rpspringuel]

Also, has anyone looked at using glyph variants to define the connecting nubs rather than creating two separate glyphs (one connecting, one not)?

[henryso]

We're close, but maybe it can fit. It depends on how many we need for the quilisma-pes. I haven't looked into glyph variants. There are nine for every shape within fusion and varying numbers for starting glyphs and ending glyphs. Quilisma-pes is actually a new can of worms because it'll be the first two-note ending glyph.

[henryso]

I think we have enough characters. We go to 0xf694, and I think we have until 0xf8ff. I have shake off the cobwebs to do this one, so please don't expect anything quickly.

[henryso]

@rpspringuel Are there any examples of figures ending in quilisma-pes that are separate from the previous figure by more than one pitch?

[rpspringuel]

That’s a question to put to the original reporter on the mailing list.

_{Sent with GitHawk}

[henryso]

Per the list, there is no further example. I can't even imagine how a stem would connect with a quilisma, so I'll implement the fusion into a quilisma-pes only at an ambitus of one. This won't require any glyphs that we don't already have.

[henryso]

Playing with this for a bit, I'm starting to think it would be better to have a different syntax for the torculus-like figure before the quilisma that ends in a stroke rather than a note. However, there are knock on effects to the fusion algorithm that I'm working through. I'm not 100% sure on the right approach yet.

[henryso]

My proposal is to use &[...] to signal the use of an alternate interpretation of a figure. In this case it could be &[stroke] or something with a better name if there are other ideas. @rpspringuel do you have any opinions on this?

[henryso]

I decided to use [shape:stroke] instead. I didn't feel there was a need to use yet another sigil.