Gets vertical skylines from grob stencils

flower/include/interval-set.hh

 /*
   This file is part of LilyPond, the GNU music typesetter.
 
   Copyright (C) 2004--2012 Han-Wen Nienhuys <hanwen@xs4all.nl>
 
   LilyPond is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.
 
   LilyPond is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
 
   You should have received a copy of the GNU General Public License
   along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
 */
 
 #ifndef INTERVAL_SET_HH
 #define INTERVAL_SET_HH
 
 #include "std-vector.hh"
 #include "interval.hh"
 
-/*
-  A union of intervals in the real line.
+class Interval_set
+{
+public:
+  Interval_set ();
 
-  Abysmal performance (quadratic) for large N, hopefully we don't have
-  that large N. In any case, this should probably be rewritten to use
-  a balanced tree.
-*/
-struct Interval_set
-{
-  vector<Interval> allowed_regions_;
+  static Interval_set interval_union (vector<Interval>);
 
-  Interval_set ();
-  void set_full ();
-  void remove_interval (Interval rm);
+  vector<Interval> const &intervals () const { return intervals_; }
+  vector<Interval>::const_iterator upper_bound (Real x) const;
+  Real nearest_point (Real x, Direction dir = CENTER) const;
+  Interval_set complement () const;
+
+private:
+  vector<Interval> intervals_;
 };
 
 #endif /* INTERVAL_SET_HH */