Orientation.h

/**********************************************************************
 *
 * 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
 *
 **********************************************************************/
 
#pragma once
 
#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::CoordinateXY& p1, const geom::CoordinateXY& p2,
                     const geom::CoordinateXY& q);
 
    static bool isCCW(const geom::CoordinateSequence* ring);
 
    static bool isCCWArea(const geom::CoordinateSequence* ring);
 
};
 
 
} // namespace geos::algorithm
} // namespace geos