Feature proposition: Polymeters and additive time signatures

[Melyn0]

Polymeters

The ability to have a different meter on an individual stave with the same pulse. Example: violin plays in 4/4, cello in 5/4, where quarter note = quarter note between them. This would require/allow bar lines that do not line up with each and also potentially for bars to spill over systems (where one line finishes a bar, but another doesn't at the end of a system).

This can be faked by changing the visual appearance of an individual stave's signature and then adding new barlines in, while making the original barlines invisible. However, dealing with ties, beaming, and flags makes this very finicky. Add to this the fact that tuplets can't cross default barlines, and it gets even more complicated. Proper support and engraving for this would be much welcome.

A simple example of polymeters.

Additive time signatures

This is more of an aside, but support for additive time signatures and for easier customisation of appearance would also be welcome. This is likely much less of a pressing matter, I presume however, as it is not hard to create this yourself by adding bar lines in and changing the text of the signature (although there is much less control on appearance).

How it tends to appear in the current version of Musescore.

Examples of other appearances.

[its-not-nice]

These exist already as feature requests, e.g.
#25101
#25092
#18334 etc.

[Melyn0]

Thank you for your reply and for pointing this out. I should have realised these. However, unless I'm mistaken, none of these requests are related to polymeters. Searching for "polymeter" under "feature" does not yield any relevant results as far as I am aware.