Orientation.h

Go to the documentation of this file.

/**********************************************************************
 *
 * GEOS - Geometry Engine Open Source
 * http://geos.osgeo.org
 *
 * Copyright (C) 2018 Paul Ramsey <pramsey@cleverlephant.ca>
 *
 * 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/Orientation.java @ 2017-09-04
 *
 **********************************************************************/

#ifndef GEOS_ALGORITHM_ORIENTATION_H
#define GEOS_ALGORITHM_ORIENTATION_H

#include <geos/export.h>
#include <geos/geom/Coordinate.h>
#include <geos/geom/CoordinateSequence.h>

namespace geos {
namespace algorithm { // geos::algorithm

class GEOS_DLL Orientation {
public:

    /* A value that indicates an orientation or turn */
    enum {
        CLOCKWISE = -1,
        COLLINEAR = 0,
        COUNTERCLOCKWISE = 1,
        RIGHT = -1,
        LEFT = 1,
        STRAIGHT = 0
    };

    static int index(const geom::Coordinate& p1, const geom::Coordinate& p2,
                     const geom::Coordinate& q);

    static bool isCCW(const geom::CoordinateSequence* ring);

};


} // namespace geos::algorithm
} // namespace geos


#endif // GEOS_ALGORITHM_ORIENTATION_H