page-layout: loose lines between systems; issue 2276

page-layout: loose lines between systems; issue 2276

Ensure enough space between systems that the baselines
of loose lines on a lower system, can always lie below
baselines of loose lines on the system above.

[Keith, 2012-02-05 07:56:21]

http://codereview.appspot.com/5624055/diff/2001/lily/page-layout-problem.cc
File lily/page-layout-problem.cc (right):

http://codereview.appspot.com/5624055/diff/2001/lily/page-layout-problem.cc#n...
lily/page-layout-problem.cc:607: Real min_distance = bottom_loose_baseline_ -
minimum_offsets_with_min_dist[i];
The springs being set here are between 'spaceable' staves, skipping over loose
lines.  
This would probably work better as 
 min_distance = bottom_loose_baseline_ 
   - minimum_offsets_with_min_dist[i]
   + minimum_offsets_with_min_dist[0];
so that it excludes protrusions above the first staff in a system, such as high
notes.  We probably want such protrusions to be allowed to interleave Dynamics
and Lyrics of the staff above.

[Keith, 2012-02-05 23:18:33]

On 2012/02/05 07:56:21, Keith wrote:
> This would probably work better as [ ... ] 
> so that it excludes protrusions above the first staff in a system, 
> such as high notes.  

Better to limit the action of this patch to situations when a loose line lies
above the first staff in a system.  We probably never want contents of Lyrics or
Chordnames to interleave with the system above.