MinimumDiameter.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.
 *
 **********************************************************************
 *
 * Last port: algorithm/MinimumDiameter.java r966
 *
 **********************************************************************/
 
#ifndef GEOS_ALGORITHM_MINIMUMDIAMETER_H
#define GEOS_ALGORITHM_MINIMUMDIAMETER_H
 
#include <geos/export.h>
 
// Forward declarations
namespace geos {
        namespace geom {
                class Geometry;
                class LineSegment;
                class LineString;
                class Coordinate;
                class CoordinateSequence;
        }
}
 
 
namespace geos {
namespace algorithm { // geos::algorithm

class GEOS_DLL MinimumDiameter {
private:
        const geom::Geometry* inputGeom;
        bool isConvex;
 
        geom::CoordinateSequence* convexHullPts;
 
        geom::LineSegment* minBaseSeg;
        geom::Coordinate* minWidthPt;
        int minPtIndex;
        double minWidth;
        void computeMinimumDiameter();
        void computeWidthConvex(const geom::Geometry* geom);

        void computeConvexRingMinDiameter(const geom::CoordinateSequence *pts);
 
        unsigned int findMaxPerpDistance(const geom::CoordinateSequence* pts,
                geom::LineSegment* seg, unsigned int startIndex);
 
        static unsigned int getNextIndex(const geom::CoordinateSequence* pts,
                unsigned int index);
 
        static double computeC(double a, double b, const geom::Coordinate &p);
 
        static geom::LineSegment computeSegmentForLine(double a, double b, double c);
 
public:
        ~MinimumDiameter();

        MinimumDiameter(const geom::Geometry* newInputGeom);

        MinimumDiameter(const geom::Geometry* newInputGeom,
                        const bool newIsConvex);

        double getLength();

        geom::Coordinate* getWidthCoordinate();

        geom::LineString* getSupportingSegment();

        geom::LineString* getDiameter();

        geom::Geometry* getMinimumRectangle();

        static geom::Geometry* getMinimumRectangle(geom::Geometry* geom);

        static geom::Geometry* getMinimumDiameter(geom::Geometry* geom);
 
};
 
} // namespace geos::algorithm
} // namespace geos
 
#endif // GEOS_ALGORITHM_MINIMUMDIAMETER_H