Dotted Barline

[rpspringuel]

A user has requested the ability to make the dotted bar line as shown in this picture:

I've seen them elsewhere in a slightly different style (bigger and fewer dots), but can't remember where off the top of my head. If I find it, I'll post an image.

To make this work we need the following:

• gabc syntax for the element
• lexer modifications to recognize the new syntax
• new glyph in the fonts
• modification to \gre@writebar for the new bar and \GreDottedBar alias

On the syntax issue, : would be the most obvious choice, but is already used for divisio maior. We could swap in | for that, but such a change to the gabc syntax is probably way too invasive for those who have been using Gregorio for a while. On the other hand I think that using | for the dotted bar and : for the divisio maior would be counter-intuitive and thus is probably not a good idea for newbies. I'm not sure if there is any other intuitive character that could be added.

We could make it a post-fix solution, say :0, but that raises the question as to whether we need dotted versions for all the current bar types and not just the divisio maior.

[henryso]

If we needed dotted versions for any bar type, then I suggest appending ? to differentiate it a little for the Dominican bars. If we only need a dotted version for divisio maior, then how about just ??

As to the the style of the dotted bar, if a single score cannot have more than one style, then I think it's good enough to just put it in the font and let people select the style by selecting a different font (or using a substitution if we want to provide multiple within the font itself).

[henryso]

Any response on this?

[rpspringuel]

If we needed dotted versions for any bar type, then I suggest appending ? to differentiate it a little for the Dominican bars. If we only need a dotted version for divisio maior, then how about just ??

That works for me. If I'm reading the above correctly, then the dotted bar is part of the "optional" syntax. A ? suggests optional quite well.

As to the the style of the dotted bar, if a single score cannot have more than one style, then I think it's good enough to just put it in the font and let people select the style by selecting a different font (or using a substitution if we want to provide multiple within the font itself).

I don't think more than one style is necessary for each score, so handling the various styles with a different font or a variant glyph seems appropriate.

As for the other context I came across this in, it was the Psalm tone that my community uses for the Magnificat of the O Antiphons. The dotted bar is used to indicate the start of the section which is skipped in the first verse (so again, related to "optional" notes):

Scan.pdf

Edit (reupload image as something that will display directly):

[henryso]

Do you think we need more than just a dotted division maior? In other words, is ? a bar modifier or a bar character?

[rpspringuel]

I've never seen anything but the dotted divisio maior.

How hard would it be to change this once implemented? Say we started with ? being a bar character and then later people started asking for other dotted bars. Would it be possible to make the switch at that point?

[henryso]

It's possible to switch. We could start with ? to mean a dotted divisio maior, and if more is needed, ? can become a shortcut for :? after we make ? a modifier. This might break scores where people do things like :? (prior to making ? a modifier) to mean a divisio maior followed by a dotted divisio maior. Alternately, we could just implement :? to mean a dotted divisio maior without implementing any other dotted bars.

[rpspringuel]

Alternately, we could just implement :? to mean a dotted divisio maior without implementing any other dotted bars.

That sounds reasonable.