Re: Bar lines

[Mats Bengtsson]

Han-Wen Nienhuys wrote:
> address@hidden writes:
>
> > Because of a question in user-lilypond, I looked at the function
> > scm/output-lib.scm: default-break-barline
> > and noticed a few problems:
> >
> > This function handles a number of bar types that are not handled
> > by Bar_line::compound_barline(...), which is a problem since
> > default-break-barline is only called at line breaks.
> >
> > "||:" is treated twice, whereas ":||" is missing, probably an
> > old copy-paste bug.
> >
> > I propose to make the following change:
> >
> > - Always call the function, not only at line breaks
>
>
> Huh? What do you mean exactly (and what problem would it solve?) 

Sorry! The alternative would be to add the "||:", ":||", "|s" and
more combinations that you could think of also in
Bar_line::compund_barline(). My idea was to keep the basic ones
in the C++ code and add the rest that only differ in how they are
treated at line breaks in the default-break-barline function.

> > - Let the function return three values "glyph in the middle
> >   of the line", "glyph at line end" and "glyph at line start".
>
>
> Do you mean a string (like now) or a molecule? 

Haven't thought about it. The default-break-barline function
should still be fairly easy to redefine in a users file, so I
wouldn't want it to build the molecules from scratch for every
special case. The idea would rather be to express what should
happen at a line break (and in the middle of a line) expressed
in terms of the basic bar line types that currently are handled
in C++.

> Yes, if bar-line gets a changeover, why not do dotted barlines too at
> the same time, in the C++ code.

Of course. We already have PS code to draw the dashed lines, don't we?
However, I'm not sure if we want a separate property dashed or if that
aspect should be included in the string argument to \bar describing the
bar type.

   /Mats