Re: exact placement rules for volta brackets?

[David Rogers]

On Fri, 31 Aug 2012 10:55:09 +0200
Marc Hohl <address@hidden> wrote:

> Hello all,
> 
> I am just about rewriting the bar line user interface and stumbled
> across a serious problem: with my new approach, the valta brackets
> are displaced.
> 
> For developing a fix, I need to know how this is properly done.
> Gould doesn't say much about the details, and this is the only
> reference I have.
> 
> For the moment, the center of the volta hook is placed over the left
> edge of the thick bar line, see the attached picture.
> This looks a bit weird, I think.
> 
> Any hints/references/improvements?


I just looked at some hand-made piano scores and a vocal score, some
older and some newer, from Baerenreiter, Breitkopf, and Schott. With
thick bar lines and volta brackets, results are not precisely all the
same. I wasn't able to tell if this was inconsistency or a rule I
couldn't perceive - I suspect just a bit of inconsistency. However, the
large majority of them were as follows:

Left sides of brackets over thick bar lines were placed so that the left
edges of the two lines matched.

Right sides of brackets over thick bar lines were placed so that the
right edges of the two lines matched.

In other words, 
a. Place the red guide line just as you have it now, touching the bar
line, on the "outside edge" relative to the bracket.

b. Make the volta bracket just touch the guide line, not centre on it.


The vast majority of volta brackets at thin (normal) bar lines are
centred on the bar line.

Whether thick bar lines or thin, these particular hand-engravers appear
to have allowed themselves a bit more flexibility about volta bracket
positioning in those places where two brackets were close to touching,
as in your picture. Those are the places of least consistency of
alignment, at least in the scores I happened to have near the top of
the pile. Probably it's just harder to get them aligned perfectly when
there's less room to work.

-- 
David R