Additive meter time signatures

[rettinghaus]

Although this is a libMEI issue, I leave it here, as Verovio is affected by this:

meter.count is treated as int but it should be read as str as it allows "additive expression":

Value of datatype a string matching the following regular expression: "\d+(.\d+)?(\s*+\s*\d+(.\d+)?)*"

(same applies to @count)
Showing a plus sign in SVG shouldn't be that hard then, is it?

[rettinghaus]

Glyph U+EA6C ("+") would be needed also.

[lpugin]

Why not http://www.smufl.org/version/latest/glyph/timeSigPlusSmall/ ?

[rettinghaus]

Yeah, makes more sense. So E08D should be it.

[lpugin]

The glyph is added. Now it is not as simple as changing to string, because this will break all the timestamp calculation. We need to think about a custom class for compound values.

[rettinghaus]

Not really. We could keep m_meterCount as an integer with the "resulting" count from something like "3+2+4+1". There should be a little function calculating the resulting count.

[lpugin]

General feature request

[craigsapp]

Here is a nice example:

http://imslp.eu/files/imglnks/euimg/5/51/IMSLP20283-PMLP47288-Bartok_violin_duets_part_I.pdf

[rettinghaus]

Support added with #2200.