BufferOp.h

/**********************************************************************
 *
 * GEOS - Geometry Engine Open Source
 * http://geos.osgeo.org
 *
 * Copyright (C) 2009-2011 Sandro Santilli <strk@kbt.io>
 * Copyright (C) 2005-2007 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: operation/buffer/BufferOp.java r378 (JTS-1.12)
 *
 **********************************************************************/

#pragma once

#include <memory> // for unique_ptr
#include <vector> // for vector

#include <geos/export.h>
#include <geos/operation/buffer/BufferParameters.h> // for enum values
#include <geos/geom/Geometry.h> // to materialize Geometry

#include <geos/util/TopologyException.h> // for composition

#ifdef _MSC_VER
#pragma warning(push)
#pragma warning(disable: 4251) // warning C4251: needs to have dll-interface to be used by clients of class
#endif

// Forward declarations
namespace geos {
namespace geom {
class PrecisionModel;
class Geometry;
}
}

namespace geos {
namespace operation { // geos.operation
namespace buffer { // geos.operation.buffer

class GEOS_DLL BufferOp {


private:

    static constexpr int MAX_PRECISION_DIGITS = 12;

    const geom::Geometry* argGeom;

    util::TopologyException saveException;

    double distance;

    BufferParameters bufParams;

    std::unique_ptr<geom::Geometry> resultGeometry;

    bool isInvertOrientation = false;

    static double precisionScaleFactor(const geom::Geometry* g,
                                       double distance, int maxPrecisionDigits);


    void computeGeometry();

    void bufferOriginalPrecision();

    void bufferReducedPrecision(int precisionDigits);

    void bufferReducedPrecision();

    void bufferFixedPrecision(const geom::PrecisionModel& fixedPM);

    static void extractPolygons(
        geom::Geometry* poly0,
        std::vector<std::unique_ptr<geom::Geometry>>& polys);

public:

    enum {
        CAP_ROUND = BufferParameters::CAP_ROUND,

        CAP_BUTT = BufferParameters::CAP_FLAT,

        CAP_SQUARE = BufferParameters::CAP_SQUARE
    };

    static std::unique_ptr<geom::Geometry> bufferOp(
        const geom::Geometry* g,
        double distance,
        int quadrantSegments = BufferParameters::DEFAULT_QUADRANT_SEGMENTS,
        int endCapStyle = BufferParameters::CAP_ROUND);

    static std::unique_ptr<geom::Geometry> bufferOp(
        const geom::Geometry* g,
        double distance,
        BufferParameters& bufParms);

    BufferOp(const geom::Geometry* g)
        :
        argGeom(g),
        bufParams(),
        resultGeometry(nullptr),
        isInvertOrientation(false)
    {
    }

    BufferOp(const geom::Geometry* g, const BufferParameters& params)
        :
        argGeom(g),
        bufParams(params),
        resultGeometry(nullptr),
        isInvertOrientation(false)
    {
    }

    inline void setEndCapStyle(int nEndCapStyle);

    inline void setQuadrantSegments(int nQuadrantSegments);

    inline void setSingleSided(bool isSingleSided);

    std::unique_ptr<geom::Geometry> getResultGeometry(double nDistance);

    static std::unique_ptr<geom::Geometry> bufferByZero(
        const geom::Geometry* geom,
        bool isBothOrientations);

};

// BufferOp inlines
void
BufferOp::setQuadrantSegments(int q)
{
    bufParams.setQuadrantSegments(q);
}

void
BufferOp::setEndCapStyle(int s)
{
    bufParams.setEndCapStyle((BufferParameters::EndCapStyle)s);
}

void
BufferOp::setSingleSided(bool isSingleSided)
{
    bufParams.setSingleSided(isSingleSided);
}

} // namespace geos::operation::buffer
} // namespace geos::operation
} // namespace geos

#ifdef _MSC_VER
#pragma warning(pop)
#endif