tuplet@bracket.place enhancements

[craigsapp]

Related to issue https://github.com/music-encoding/guidelines/issues/99 it would be useful for additional options to the tuplet@bracket.place attribute:

value	meaning
above	place tuplet bracket above the notes to which it is attached
below	place tuplet bracket below the notes to which it is attached
head	place tuplet bracket on the note head side of the notes to which it is attached
stem	place tuplet bracket on the stem side of the notes to which it is attached

The reason for the addition of the last two are related to nineteenth-century editions of music, where the most typical position of the tuplet bracket is on the notehead side of the notes. Verovio's default positioning is on the stem side of the notes.

Example from the first edition of Beethoven Op. 1/1 piano sonata:

The tuplet bracket (number) is not above the notes in such cases, but rather on the head side of the notes. Here is an example of both on the same system:

Verovio's style is to place the tuplet bracket/numbers on the stem sides of the notes by default (in a more modern convention):

Alternatively or in addition, there could be a verovio option that sets the default position of brackets (when there is a single layer active in a measure). The default option would be that brackets are placed on the stem sides of notes, and the option would switch this to the head sides of notes. Having this option would be advantageous, since this would prevent the need to adjust the data to change tuplet bracket placement styles.

[rettinghaus]

This is an MEI issue, please report it to https://github.com/music-encoding/music-encoding/issues

[craigsapp]

Technically it is open over here: music-encoding/guidelines#99 but currently latent.