LineSegment.h

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/**********************************************************************
 *
 * GEOS - Geometry Engine Open Source
 * http://geos.osgeo.org
 *
 * Copyright (C) 2009 2011 Sandro Santilli <strk@kbt.io>
 * Copyright (C) 2005-2006 Refractions Research Inc.
 * Copyright (C) 2001-2002 Vivid Solutions 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: geom/LineSegment.java r18 (JTS-1.11)
 *
 **********************************************************************/

#ifndef GEOS_GEOM_LINESEGMENT_H
#define GEOS_GEOM_LINESEGMENT_H

#include <geos/export.h>
#include <geos/geom/Coordinate.h> // for composition

#include <geos/inline.h>

#include <array>
#include <iostream> // for ostream
#include <functional> // for std::hash
#include <memory> // for unique_ptr

// Forward declarations
namespace geos {
namespace geom {
class CoordinateSequence;
class GeometryFactory;
class LineString;
}
}

namespace geos {
namespace geom { // geos::geom

class GEOS_DLL LineSegment {
public:

    friend std::ostream& operator<< (std::ostream& o, const LineSegment& l);

    Coordinate p0; 

    Coordinate p1; 

    LineSegment();

    LineSegment(const Coordinate& c0, const Coordinate& c1);

    LineSegment(double x0, double y0, double x1, double y1);

    void setCoordinates(const Coordinate& c0, const Coordinate& c1);

    // obsoleted, use operator[] instead
    //const Coordinate& getCoordinate(std::size_t i) const;

    const Coordinate& operator[](std::size_t i) const;
    Coordinate& operator[](std::size_t i);

    void setCoordinates(const LineSegment& ls);

    double getLength() const;

    bool isHorizontal() const;

    bool isVertical() const;

    int orientationIndex(const LineSegment& seg) const;

    // TODO: deprecate this
    int orientationIndex(const LineSegment* seg) const;

    int orientationIndex(const Coordinate& p) const;

    void reverse();

    //
    void normalize();

    double angle() const;

    //
    void midPoint(Coordinate& ret) const;

    double distance(const LineSegment& ls) const;

    double distance(const Coordinate& p) const;

    double distancePerpendicular(const Coordinate& p) const;

    void pointAlong(double segmentLengthFraction, Coordinate& ret) const;

    void pointAlongOffset(double segmentLengthFraction,
                          double offsetDistance,
                          Coordinate& ret) const;

    double projectionFactor(const Coordinate& p) const;

    double segmentFraction(const Coordinate& inputPt) const;

    void project(const Coordinate& p, Coordinate& ret) const;

    bool project(const LineSegment& seg, LineSegment& ret) const;

    //
    void closestPoint(const Coordinate& p, Coordinate& ret) const;

    int compareTo(const LineSegment& other) const;

    bool equalsTopo(const LineSegment& other) const;

    std::array<Coordinate, 2> closestPoints(const LineSegment& line);

    std::array<Coordinate, 2> closestPoints(const LineSegment* line);

    Coordinate intersection(const LineSegment& line) const;

    Coordinate lineIntersection(const LineSegment& line) const;

    std::unique_ptr<LineString> toGeometry(const GeometryFactory& gf) const;

    struct HashCode {
        size_t operator()(const LineSegment & s) const {
            size_t h = std::hash<double>{}(s.p0.x);
            h ^= (std::hash<double>{}(s.p0.y) << 1);
            h ^= (std::hash<double>{}(s.p1.x) << 1);
            return h ^ (std::hash<double>{}(s.p1.y) << 1);
        }
    };
};

std::ostream& operator<< (std::ostream& o, const LineSegment& l);

bool operator==(const LineSegment& a, const LineSegment& b);


} // namespace geos::geom
} // namespace geos

#ifdef GEOS_INLINE
# include "geos/geom/LineSegment.inl"
#endif

#endif // ndef GEOS_GEOM_LINESEGMENT_H