Re: Help with page breaking code

[Keith OHara]

David Kastrup <dak <at> gnu.org> writes:

> #(set! empty-stencil (ly:make-stencil '() empty-interval empty-interval))
> \markup \fill-line { }

> Basically, the first \markup produces an empty stencil with extents
> (+inf.0 . -inf.0) and the page breaking code goes bonkers on that.
> 

\paper {annotate-spacing = ##t}
indicates proper estimates for any scores after the \fill-line, and
indirectly shows zero space allowed for the \fill-line, so the
height estimations seem reasonable.

The problem appears only when \fill-line is the first markup, so maybe
a bad initialization in one of
page-breaking.cc  page-layout-problem.cc  page-spacing.cc

At some point, you made a change so that \line {} would return a
non-empty extent; possibly \fill-line needs that as well.

Of course I recommend first fixing the bugs you can with the existing
definition of "empty" stencil extents.  The redundant line in dots.cc,
the ref-point for \parenthesize, and having the spacing functions
recognize \hspace and space appropriately, can be resolved before
changing 'empty-stencil'.