Re: Allow fixed spacing of symbols in church rests (issue 319910043 by address@hidden)

[david . nalesnik]

On 2016/12/30 16:59:55, Dan Eble wrote:
> On 2016/12/29 17:47:46, david.nalesnik wrote:
> > Please review.  Thanks!

> I haven't reviewed the code, but the description makes me wonder, is
the current
> behavior not a bug?  Gould says "In tradition engraving," which
appears to be
> her term for the style using church rests, "a rest bar takes the space
the
> graphic symbol needs ..." (Behind Bars, p.565).  Although she goes on
to
> recommend against "tradition engraving," it seems that the bars should
be sized
> to the rests, not the other way around.

> Is it important to preserve the old algorithm at all?  If not, call it
a bug and
> throw it out.  If it is important to preserve, could it be handled
with a
> conversion rule so that your new algorithm can be the default?

I've had time to think about this, and I think my comments below will be
a more direct response
to your concerns!

Bars *are* sized to fit the rest, but this issue is complicated by
available space.

When ragged-right is #t, bars fit the rest, though an effort is made to
give extra space to rests
proportional to their duration (the property space-increment).  Gould is
in favor of this practice.  Setting
spacing-increment to 0 gives you measures with only enough space to
contain their rests:

{
  \override MultiMeasureRest.expand-limit = 101
  \override MultiMeasureRest.space-increment = 0
  \compressFullBarRests
  R1*3
  R1*5
  R1*7
  R1*9
  R1*101
}

But when the contents of the measure aren't the only factors in deciding
measure size, what happens
to the church rest?  The engraving examples I cited allow flexibility in
the spacing of church rest
symbols.  When the rest is too diffuse, however, it becomes harder to
take in.

So I believe that the bug here is that LilyPond does not limit the
stretchability of the
rest.  The third patch set addresses that.


https://codereview.appspot.com/319910043/