MonotoneChainEdge.h

/**********************************************************************
 *
 * GEOS - Geometry Engine Open Source
 * http://geos.osgeo.org
 *
 * Copyright (C) 2005-2006 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.
 *
 **********************************************************************/
 
#ifndef GEOS_GEOMGRAPH_INDEX_MONOTONECHAINEDGE_H
#define GEOS_GEOMGRAPH_INDEX_MONOTONECHAINEDGE_H
 
#include <geos/export.h>
#include <geos/geom/Envelope.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 CoordinateSequence;
        }
        namespace geomgraph {
                class Edge;
                namespace index {
                        class SegmentIntersector;
                }
        }
}
 
namespace geos {
namespace geomgraph { // geos::geomgraph
namespace index { // geos::geomgraph::index
 
class GEOS_DLL MonotoneChainEdge {
public:
        //MonotoneChainEdge();
        ~MonotoneChainEdge();
        MonotoneChainEdge(Edge *newE);
        const geom::CoordinateSequence* getCoordinates();
        std::vector<int>& getStartIndexes();
        double getMinX(int chainIndex);
        double getMaxX(int chainIndex);
 
        void computeIntersects(const MonotoneChainEdge &mce,
                SegmentIntersector &si);
 
        void computeIntersectsForChain(int chainIndex0,
                const MonotoneChainEdge &mce, int chainIndex1,
                SegmentIntersector &si);
 
protected:
        Edge *e;
        const geom::CoordinateSequence* pts; // cache a reference to the coord array, for efficiency
        // the lists of start/end indexes of the monotone chains.
        // Includes the end point of the edge as a sentinel
        std::vector<int> startIndex;
        // these envelopes are created once and reused
        geom::Envelope env1;
        geom::Envelope env2;
private:
        void computeIntersectsForChain(int start0, int end0,
                const MonotoneChainEdge &mce,
                int start1, int end1,
                SegmentIntersector &ei);
};
 
} // namespace geos.geomgraph.index
} // namespace geos.geomgraph
} // namespace geos
 
#ifdef _MSC_VER
#pragma warning(pop)
#endif
 
#endif