PrecisionUtil.h

/**********************************************************************
 *
 * GEOS - Geometry Engine Open Source
 * http://geos.osgeo.org
 *
 * Copyright (C) 2020 Paul Ramsey <pramsey@cleverelephant.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.
 *
 **********************************************************************/
 
#pragma once
 
#include <geos/export.h>
 
#include <geos/geom/CoordinateFilter.h>
#include <geos/geom/Coordinate.h>
 
#include <vector>
#include <map>
 
 
// Forward declarations
namespace geos {
namespace geom {
class Geometry;
class Envelope;
class PrecisionModel;
}
namespace operation {
}
}
 
namespace geos {      // geos.
namespace operation { // geos.operation
namespace overlayng { // geos.operation.overlayng

class GEOS_DLL PrecisionUtil {
    using Geometry = geos::geom::Geometry;
    using Envelope = geos::geom::Envelope;
    using PrecisionModel = geos::geom::PrecisionModel;
    using CoordinateFilter = geos::geom::CoordinateFilter;
 
private:
 
    static double robustScale(double inherentScale, double safeScale);

    static double maxBoundMagnitude(const Envelope* env);

    static double precisionScale(double value, int precisionDigits);
 
 
 
public:
 
    static constexpr int MAX_ROBUST_DP_DIGITS = 14;
 
    PrecisionUtil() {};

    static PrecisionModel robustPM(const Geometry* a, const Geometry* b);

    static PrecisionModel robustPM(const Geometry* a);

    static double robustScale(const Geometry* a, const Geometry* b);

    static double robustScale(const Geometry* a);

    static double safeScale(double value);

    static double safeScale(const Geometry* geom);

    static double safeScale(const Geometry* a, const Geometry* b);

    static double inherentScale(double value);

    static double inherentScale(const Geometry* geom);

    static double inherentScale(const Geometry* a, const Geometry* b);

    static int numberOfDecimals(double value);

    class GEOS_DLL InherentScaleFilter: public CoordinateFilter {
 
        private:
 
            double scale;
 
            void updateScaleMax(double value) {
                double scaleVal = PrecisionUtil::inherentScale(value);
                if (scaleVal > scale) {
                    scale = scaleVal;
                }
            }
 
        public:
 
            InherentScaleFilter()
                : scale(0.0)
                {}
 
            void filter_ro(const geom::Coordinate* coord) override
            {
                updateScaleMax(coord->x);
                updateScaleMax(coord->y);
            }
 
            double getScale() const {
                return scale;
            }
    };
 
 
};
 
 
} // namespace geos.operation.overlayng
} // namespace geos.operation
} // namespace geos