Creates FingeringColumn to prevent vertical fingering intersections.

Creates FingeringColumn to prevent vertical fingering intersections.

Fans out Fingering grobs from the middle of the column in either
direction to avoid intersections.

[Graham Percival, 2012-08-27 08:49:51]

http://codereview.appspot.com/6472056/diff/1/lily/fingering-column-engraver.cc
File lily/fingering-column-engraver.cc (right):

http://codereview.appspot.com/6472056/diff/1/lily/fingering-column-engraver.c...
lily/fingering-column-engraver.cc:56: {
I don't think that we shouldn't have a { here.  Could you run fixcc.sh on this?

[Graham Percival, 2012-08-27 10:02:04]

No, I'm wrong about that.  astyle doesn't mind about the { as the only changes
are removing trailing whitespace (could you fix emacs so it stops adding it?)
and one line-break just before the }; on line 59 of lily/fingering-column.cc.

[dak, 2012-08-29 18:28:05]

http://codereview.appspot.com/6472056/diff/1/lily/fingering-column.cc
File lily/fingering-column.cc (right):

http://codereview.appspot.com/6472056/diff/1/lily/fingering-column.cc#newcode38
lily/fingering-column.cc:38: map<Grob *, bool> shifted;
It seems quite pointless to use a map here instead of a bool array, since after
sorting, grob positions are not changed and you can just index a bool array
using
shifted[x]
rather than
shifted[fingerings[x]] employing a map.  I think we can assume that we don't
have duplicate grobs in here.

http://codereview.appspot.com/6472056/diff/1/lily/fingering-column.cc#newcode65
lily/fingering-column.cc:65: for (vsize i = min (fingerings.size () - 1,
fingerings.size () / 2 + 1); i >= 1; i--)
The commit message talks about "fanning out" from the middle of the column, but
there is no comment whatsoever in here, and it is totally unclear what this is
supposed to do.  Add a few comments here, and preferably some ASCII art in
comments illustrating problem and solution.