convex_hull.h

Go to the documentation of this file.

// -*-c++-*-

 
/*
 *Copyright:
 
 Copyright (C) Hidehisa Akiyama
 
 This code is free software; you can redistribute it and/or
 modify it under the terms of the GNU Lesser General Public
 License as published by the Free Software Foundation; either
 version 3 of the License, or (at your option) any later version.
 
 This library 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
 Lesser General Public License for more details.
 
 You should have received a copy of the GNU Lesser General Public
 License along with this library; if not, write to the Free Software
 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 
 *EndCopyright:
 */
 
#ifndef RCSC_GEOM_CONVEX_HULL_H
#define RCSC_GEOM_CONVEX_HULL_H
 
#include "geom/vector_2d.h"
#include "geom/segment_2d.h"
#include "geom/polygon_2d.h"
 
#include <vector>
#include <set>
 
namespace rcsc {
 
class ConvexHull {
public:
    typedef std::vector< Vector2D > PointCont; 
    typedef std::vector< Vector2D > VertexCont; 
    typedef std::vector< Segment2D > EdgeCont; 

    enum MethodType {
        DirectMethod,
        WrappingMethod,
        GrahamScan,
        // IncrementalMethod,
        // DivideConquer,
        // QuickMethod,
        // InnerPointsElimination,
    };
 
private:
 
    PointCont M_input_points; 
 
    VertexCont M_vertices; 
    EdgeCont M_edges; 
 
 
    // not used
    ConvexHull( const ConvexHull & );
    ConvexHull & operator=( const ConvexHull & );
 
public:

    ConvexHull();

    ConvexHull( const PointCont & v );

    void clear();

    void clearResults();

    void addPoint( const Vector2D & p )
      {
          M_input_points.push_back( p );
      }

    void addPoints( const PointCont & v )
      {
          M_input_points.insert( M_input_points.end(), v.begin(), v.end() );
      }

    // void compute();

    void compute( const MethodType type = WrappingMethod );

    const PointCont & inputPoints() const
      {
          return M_input_points;
      }

    const VertexCont & vertices() const
      {
          return M_vertices;
      }

    const EdgeCont & edges() const
      {
          return M_edges;
      }
 
private:

    void computeDirectMethod();

    void computeWrappingMethod();

    void computeGrahamScan();

    // void computeIncrementalMethod();

    // void computeDivideAndConquer();

    // void computeQuickMethod();

    // void computeInnerPointsElimination();
 
private:

    size_t getMinPointIndex() const;
 
    void sortPointsByAngleFrom( const size_t index );
 
public:

    Polygon2D toPolygon() const;

    std::ostream & printInputPoints( std::ostream & os ) const;

    std::ostream & printVertices( std::ostream & os ) const;

    std::ostream & printEdges( std::ostream & os ) const;
 
};
 
}
 
#endif