Triangle.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.
 *
 **********************************************************************/
 
#pragma once
 
#include <geos/export.h>
#include <geos/geom/Coordinate.h>
 
namespace geos {
namespace geom { // geos::geom
 
class GEOS_DLL Triangle {
public:
    CoordinateXY p0, p1, p2;
 
    Triangle(const CoordinateXY& nP0, const CoordinateXY& nP1, const CoordinateXY& nP2)
        : p0(nP0)
        , p1(nP1)
        , p2(nP2) {}
 
 
    void inCentre(CoordinateXY& resultPoint);
 
    static CoordinateXY inCentre(
        const CoordinateXY& p0,
        const CoordinateXY& p1,
        const CoordinateXY& p2);
 
    void circumcentre(CoordinateXY& resultPoint);
 
    void circumcentreDD(CoordinateXY& resultPoint);
 
    static const CoordinateXY circumcentre(const CoordinateXY& p0, const CoordinateXY& p1, const CoordinateXY& p2);
 
    static double circumradius(const CoordinateXY& a, const CoordinateXY& b, const CoordinateXY& c);
 
    double circumradius() const
    {
        return circumradius(p0, p1, p2);
    };
 
    bool isIsoceles();
 
    static bool isAcute(const CoordinateXY& a, const CoordinateXY& b, const CoordinateXY& c);
 
    static bool isCCW(const CoordinateXY& a, const CoordinateXY& b, const CoordinateXY& c);
 
 
    static bool intersects(const CoordinateXY& a, const CoordinateXY& b, const CoordinateXY& c,
        const CoordinateXY& p);
 
 
    bool intersects(const CoordinateXY& p) { return intersects(p0, p1, p2, p); };
 
    bool isCCW() { return isCCW(p0, p1, p2); };
 
    bool isAcute() { return isAcute(p0, p1, p2); };
 
    static double longestSideLength(
        const CoordinateXY& a,
        const CoordinateXY& b,
        const CoordinateXY& c);
 
    static double length(const CoordinateXY& a, const CoordinateXY& b, const CoordinateXY& c);
 
    double length() const;
 
    static double area(const CoordinateXY& a, const CoordinateXY& b, const CoordinateXY& c);
 
    double area() const;
 
private:
 
    double det(double m00, double m01, double m10, double m11) const;
 
};
 
 
 
} // namespace geos::geom
} // namespace geos