OverlayLabeller.h

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/**********************************************************************
 *
 * 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/Location.h>
#include <geos/operation/overlayng/OverlayGraph.h>

#include <vector>
#include <deque>

// Forward declarations
namespace geos {
namespace geom {
class Coordinate;
}
namespace operation {
namespace overlayng {
class OverlayLabel;
class OverlayGraph;
class OverlayEdge;
class InputGeometry;
}
}
}

namespace geos {      // geos.
namespace operation { // geos.operation
namespace overlayng { // geos.operation.overlayng


class GEOS_DLL OverlayLabeller {

private:

    // Members
    OverlayGraph* graph;
    InputGeometry* inputGeometry;
    std::vector<OverlayEdge*>& edges;

    static OverlayEdge* findPropagationStartEdge(OverlayEdge* nodeEdge, int geomIndex);

    void labelCollapsedEdges();
    void labelCollapsedEdge(OverlayEdge* edge, int geomIndex);

    void labelConnectedLinearEdges();
    void propagateLinearLocations(int geomIndex);
    static void propagateLinearLocationAtNode(OverlayEdge* eNode, int geomIndex, bool isInputLine, std::deque<OverlayEdge*>& edgeStack);

    static std::vector<OverlayEdge*> findLinearEdgesWithLocation(std::vector<OverlayEdge*>& edges, int geomIndex);

    void labelDisconnectedEdges();

    void labelDisconnectedEdge(OverlayEdge* edge, int geomIndex);

    geom::Location locateEdge(int geomIndex, OverlayEdge* edge);

    geom::Location locateEdgeBothEnds(int geomIndex, OverlayEdge* edge);

    void labelAreaNodeEdges(std::vector<OverlayEdge*>& nodes);



public:

    OverlayLabeller(OverlayGraph* p_graph, InputGeometry* p_inputGeometry)
        : graph(p_graph)
        , inputGeometry(p_inputGeometry)
        , edges(p_graph->getEdges())
    {}

    void computeLabelling();

    void propagateAreaLocations(OverlayEdge* nodeEdge, int geomIndex);

    void markResultAreaEdges(int overlayOpCode);

    void markInResultArea(OverlayEdge* e, int overlayOpCode);

    void unmarkDuplicateEdgesFromResultArea();


};


} // namespace geos.operation.overlayng
} // namespace geos.operation
} // namespace geos