overlayng/PolygonBuilder.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/Polygon.h>
#include <geos/operation/overlayng/OverlayEdge.h>
#include <geos/operation/overlayng/OverlayEdgeRing.h>
#include <geos/operation/overlayng/MaximalEdgeRing.h>
 
#include <vector>
 
 
// Forward declarations
namespace geos {
namespace geom {
class GeometryFactory;
class Geometry;
class Polygon;
}
namespace operation {
namespace overlayng {
class Edge;
}
}
}
 
namespace geos {      // geos.
namespace operation { // geos.operation
namespace overlayng { // geos.operation.overlayng
 
class GEOS_DLL PolygonBuilder {
 
private:
 
    // Members
    const geom::GeometryFactory* geometryFactory;
    std::vector<OverlayEdgeRing*> shellList;
    std::vector<OverlayEdgeRing*> freeHoleList;
    bool isEnforcePolygonal;
 
    // Storage
    std::vector<std::unique_ptr<OverlayEdgeRing>> vecOER;
 
    std::vector<std::unique_ptr<geom::Polygon>> computePolygons(const std::vector<OverlayEdgeRing*>& shellList) const;
 
    void buildRings(const std::vector<OverlayEdge*>& resultAreaEdges);
 
    static void linkResultAreaEdgesMax(const std::vector<OverlayEdge*>& resultEdges);
 
    static std::vector<std::unique_ptr<MaximalEdgeRing>>
        buildMaximalRings(const std::vector<OverlayEdge *> &edges);
 
    std::vector<OverlayEdgeRing*> storeMinimalRings(std::vector<std::unique_ptr<OverlayEdgeRing>>& minRings);
 
    void buildMinimalRings(const std::vector<std::unique_ptr<MaximalEdgeRing>>& maxRings);
 
    void assignShellsAndHoles(const std::vector<OverlayEdgeRing *> &minRings);
 
    static OverlayEdgeRing* findSingleShell(const std::vector<OverlayEdgeRing *> &edgeRings) ;
 
    static void assignHoles(OverlayEdgeRing* shell, const std::vector<OverlayEdgeRing *> &edgeRings);
 
 
    void placeFreeHoles(const std::vector<OverlayEdgeRing*> & shellList, const std::vector<OverlayEdgeRing*>& freeHoleList) const;
 
 
 
public:
 
    PolygonBuilder(std::vector<OverlayEdge*>& resultAreaEdges, const geom::GeometryFactory* geomFact)
        : geometryFactory(geomFact)
        , isEnforcePolygonal(true)
    {
        buildRings(resultAreaEdges);
    }
 
    PolygonBuilder(std::vector<OverlayEdge*>& resultAreaEdges, const geom::GeometryFactory* geomFact, bool p_isEnforcePolygonal)
        : geometryFactory(geomFact)
        , isEnforcePolygonal(p_isEnforcePolygonal)
    {
        buildRings(resultAreaEdges);
    }
 
    PolygonBuilder(const PolygonBuilder&) = delete;
    PolygonBuilder& operator=(const PolygonBuilder&) = delete;
 
    // Methods
    std::vector<std::unique_ptr<geom::Polygon>> getPolygons() const;
    std::vector<OverlayEdgeRing*> getShellRings() const;
 
 
};
 
 
} // namespace geos.operation.overlayng
} // namespace geos.operation
} // namespace geos