PointPairDistance.h

/**********************************************************************
 *
 * GEOS - Geometry Engine Open Source
 * http://geos.osgeo.org
 *
 * Copyright (C) 2009  Sandro Santilli <strk@keybit.net>
 *
 * This is free software; you can redistribute and/or modify it under
 * the terms of the GNU Lesser General Public Licence as published
 * by the Free Software Foundation. 
 * See the COPYING file for more information.
 *
 **********************************************************************
 *
 * Last port: algorithm/distance/PointPairDistance.java 1.1 (JTS-1.9)
 *
 **********************************************************************/
 
#ifndef GEOS_ALGORITHM_DISTANCE_POINTPAIRDISTANCE_H
#define GEOS_ALGORITHM_DISTANCE_POINTPAIRDISTANCE_H
 
#include <geos/platform.h> // for DoubleNotANumber
#include <geos/geom/Coordinate.h> // for inlines
 
#include <vector> // for composition
#include <cassert>
 
namespace geos {
namespace algorithm { // geos::algorithm
namespace distance { // geos::algorithm::distance

class PointPairDistance
{
public:
 
        PointPairDistance()
                :
                pt(2),
                distance(DoubleNotANumber),
                isNull(true)
        {
                assert(pt.size() == 2);
        }
 
        void initialize()
        {
                isNull = true;
        }
 
        void initialize(const geom::Coordinate& p0, const geom::Coordinate& p1)
        {
                pt[0] = p0;
                pt[1] = p1;
                distance = p0.distance(p1);
                isNull = false;
        }
 
        double getDistance() const
        {
                return distance;
        }
 
        const std::vector<geom::Coordinate>& getCoordinates() const
        {
                return pt;
        }
 
        const geom::Coordinate& getCoordinate(unsigned int i) const
        {
                assert(i<pt.size());
                return pt[i];
        }
 
        void setMaximum(const PointPairDistance& ptDist)
        {
                setMaximum(ptDist.pt[0], ptDist.pt[1]);
        }
 
        void setMaximum(const geom::Coordinate& p0, const geom::Coordinate& p1)
        {
                if (isNull) {
                        initialize(p0, p1);
                        return;
                }
                double dist = p0.distance(p1);
                if (dist > distance)
                        initialize(p0, p1, dist);
        }
 
        void setMinimum(const PointPairDistance& ptDist)
        {
                setMinimum(ptDist.pt[0], ptDist.pt[1]);
        }
 
        void setMinimum(const geom::Coordinate& p0, const geom::Coordinate& p1)
        {
                if (isNull) {
                        initialize(p0, p1);
                        return;
                }
                double dist = p0.distance(p1);
                if (dist < distance)
                        initialize(p0, p1, dist);
        }
 
private:

        void initialize(const geom::Coordinate& p0, const geom::Coordinate& p1,
                        double dist)
        {
                pt[0] = p0;
                pt[1] = p1;
                distance = dist;
                isNull = false;
        }
 
        std::vector<geom::Coordinate> pt;
 
        double distance;
 
        bool isNull;
};
 
} // geos::algorithm::distance
} // geos::algorithm
} // geos
 
#endif // GEOS_ALGORITHM_DISTANCE_POINTPAIRDISTANCE_H