RayCrossingCounter.h

/**********************************************************************
 *
 * GEOS - Geometry Engine Open Source
 * http://geos.osgeo.org
 *
 * Copyright (C) 2006 Refractions Research Inc.
 *
 * 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/RayCrossingCounter.java rev. 1.2 (JTS-1.9)
 *
 **********************************************************************/

#pragma once

#include <geos/export.h>
#include <geos/geom/Location.h>

#include <array>
#include <vector>

// forward declarations
namespace geos {
namespace geom {
class Coordinate;
class CoordinateXY;
class CoordinateSequence;
class CircularArc;
class Curve;
}
}


namespace geos {
namespace algorithm {

class GEOS_DLL RayCrossingCounter {
private:
    const geom::CoordinateXY& point;

    std::size_t crossingCount;

    // true if the test point lies on an input segment
    bool isPointOnSegment;

    // Declare type as noncopyable
    RayCrossingCounter(const RayCrossingCounter& other) = delete;
    RayCrossingCounter& operator=(const RayCrossingCounter& rhs) = delete;

public:
    static geom::Location locatePointInRing(const geom::CoordinateXY& p,
                                 const geom::CoordinateSequence& ring);

    static geom::Location locatePointInRing(const geom::CoordinateXY& p,
                                 const std::vector<const geom::Coordinate*>& ring);

    static geom::Location locatePointInRing(const geom::CoordinateXY& p,
                                 const geom::Curve& ring);

    RayCrossingCounter(const geom::CoordinateXY& p_point)
        : point(p_point),
          crossingCount(0),
          isPointOnSegment(false)
    { }

    void countSegment(const geom::CoordinateXY& p1,
                      const geom::CoordinateXY& p2);

    void countArc(const geom::CoordinateXY& p1,
                  const geom::CoordinateXY& p2,
                  const geom::CoordinateXY& p3);

    void processSequence(const geom::CoordinateSequence& seq, bool isLinear);

    bool
    isOnSegment() const
    {
        return isPointOnSegment;
    }

    geom::Location getLocation() const;

    bool isPointInPolygon() const;

    std::size_t getCount() const { return crossingCount; };

    static bool shouldCountCrossing(const geom::CircularArc& arc, const geom::CoordinateXY& q);

    static std::array<geom::CoordinateXY, 2>
    pointsIntersectingHorizontalRay(const geom::CircularArc& arc, const geom::CoordinateXY& origin);

};

} // geos::algorithm
} // geos