MCIndexSegmentSetMutualIntersector.h

/**********************************************************************
 *
 * GEOS - Geometry Engine Open Source
 * http://geos.osgeo.org
 *
 * Copyright (C) 2006 Refractions Research 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.
 *
 **********************************************************************/
 
#pragma once
 
#include <geos/noding/SegmentSetMutualIntersector.h> // inherited
#include <geos/index/chain/MonotoneChainOverlapAction.h> // inherited
#include <geos/index/chain/MonotoneChain.h> // inherited
#include <geos/index/strtree/TemplateSTRtree.h> // inherited
 
namespace geos {
namespace geom {
    class Envelope;
}
namespace index {
    class SpatialIndex;
}
namespace noding {
    class SegmentString;
    class SegmentIntersector;
}
}
 
//using namespace geos::index::strtree;
 
namespace geos {
namespace noding { // geos::noding
 
class GEOS_DLL MCIndexSegmentSetMutualIntersector : public SegmentSetMutualIntersector {
public:
 
    MCIndexSegmentSetMutualIntersector(double p_tolerance)
        : monoChains()
        , indexCounter(0)
        , processCounter(0)
        , nOverlaps(0)
        , overlapTolerance(p_tolerance)
        , indexBuilt(false)
        , envelope(nullptr)
    {}
 
    MCIndexSegmentSetMutualIntersector(const geom::Envelope* p_envelope)
        : monoChains()
        , indexCounter(0)
        , processCounter(0)
        , nOverlaps(0)
        , overlapTolerance(0.0)
        , indexBuilt(false)
        , envelope(p_envelope)
    {}
 
    MCIndexSegmentSetMutualIntersector()
        : MCIndexSegmentSetMutualIntersector(0.0)
    {}
 
    ~MCIndexSegmentSetMutualIntersector() override
    {};
 
    index::SpatialIndex*
    getIndex()
    {
        return &index;
    }
 
    void setBaseSegments(SegmentString::ConstVect* segStrings) override;
 
    // NOTE: re-populates the MonotoneChain vector with newly created chains
    void process(SegmentString::ConstVect* segStrings) override;
 
    class SegmentOverlapAction : public index::chain::MonotoneChainOverlapAction {
    private:
        SegmentIntersector& si;
 
        // Declare type as noncopyable
        SegmentOverlapAction(const SegmentOverlapAction& other) = delete;
        SegmentOverlapAction& operator=(const SegmentOverlapAction& rhs) = delete;
 
    public:
        SegmentOverlapAction(SegmentIntersector& p_si) :
            index::chain::MonotoneChainOverlapAction(), si(p_si)
        {}
 
        void overlap(const index::chain::MonotoneChain& mc1, std::size_t start1,
                     const index::chain::MonotoneChain& mc2, std::size_t start2) override;
    };
 
    MCIndexSegmentSetMutualIntersector(const MCIndexSegmentSetMutualIntersector&) = delete;
    MCIndexSegmentSetMutualIntersector& operator=(const MCIndexSegmentSetMutualIntersector&) = delete;
 
private:
 
    typedef std::vector<index::chain::MonotoneChain> MonoChains;
    MonoChains monoChains;
 
    /*
     * The index::SpatialIndex used should be something that supports
     * envelope (range) queries efficiently (such as a index::quadtree::Quadtree
     * or index::strtree::STRtree).
     */
    index::strtree::TemplateSTRtree<const index::chain::MonotoneChain*> index;
    int indexCounter;
    int processCounter;
    // statistics
    int nOverlaps;
    double overlapTolerance;
 
    /* memory management helper, holds MonotoneChain objects used
     * in the SpatialIndex. It's cleared when the SpatialIndex is
     */
    bool indexBuilt;
    MonoChains indexChains;
    const geom::Envelope* envelope;
 
    void addToIndex(SegmentString* segStr);
 
    void intersectChains();
 
    void addToMonoChains(SegmentString* segStr);
 
};
 
} // namespace geos::noding
} // namespace geos