OffsetCurveBuilder.h

/**********************************************************************
 * $Id: OffsetCurveBuilder.h 2559 2009-06-08 10:07:05Z strk $
 *
 * GEOS - Geometry Engine Open Source
 * http://geos.refractions.net
 *
 * Copyright (C) 2009  Sandro Santilli <strk@keybit.net>
 * Copyright (C) 2006-2007 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.
 *
 **********************************************************************
 *
 * Last port: operation/buffer/OffsetCurveBuilder.java rev. 1.30 (JTS-1.10)
 *
 **********************************************************************/

#ifndef GEOS_OP_BUFFER_OFFSETCURVEBUILDER_H
#define GEOS_OP_BUFFER_OFFSETCURVEBUILDER_H

#include <geos/export.h>

#include <vector>

#include <geos/algorithm/LineIntersector.h> // for composition
#include <geos/geom/Coordinate.h> // for composition
#include <geos/geom/LineSegment.h> // for composition
#include <geos/operation/buffer/BufferParameters.h> // for composition

// Forward declarations
namespace geos {
        namespace geom {
                class CoordinateSequence;
                class PrecisionModel;
        }
        namespace operation {
                namespace buffer {
                        class OffsetCurveVertexList;
                }
        }
}

namespace geos {
namespace operation { // geos.operation
namespace buffer { // geos.operation.buffer

class GEOS_DLL OffsetCurveBuilder {
public:

        /*
         * @param nBufParams buffer parameters, this object will
         *                   keep a reference to the passed parameters
         *                   so caller must make sure the object is
         *                   kept alive for the whole lifetime of
         *                   the buffer builder.
         */
        OffsetCurveBuilder(const geom::PrecisionModel *newPrecisionModel,
                        const BufferParameters& bufParams);

        ~OffsetCurveBuilder();

        void getLineCurve(const geom::CoordinateSequence* inputPts,
                          double distance,
                          std::vector<geom::CoordinateSequence*>& lineList);

        void getSingleSidedLineCurve(const geom::CoordinateSequence* inputPts, 
             double distance, std::vector<geom::CoordinateSequence*>& lineList,
             bool leftSide, bool rightSide ) ;

        void getRingCurve(const geom::CoordinateSequence *inputPts, int side,
                          double distance,
                          std::vector<geom::CoordinateSequence*>& lineList);


private:

        //
        void addMitreJoin(const geom::Coordinate& p,
                          const geom::LineSegment& offset0,
                          const geom::LineSegment& offset1,
                          double distance);

        //
        void addLimitedMitreJoin(
                          const geom::LineSegment& offset0,
                          const geom::LineSegment& offset1,
                          double distance, double mitreLimit);

        // 
        void addBevelJoin(const geom::LineSegment& offset0,
                          const geom::LineSegment& offset1);

   
        static const double CURVE_VERTEX_SNAP_DISTANCE_FACTOR; //  1.0E-6;

        static const double PI; //  3.14159265358979

        static const double MAX_CLOSING_SEG_LEN; // 3.0

        static const double OFFSET_SEGMENT_SEPARATION_FACTOR; // 1.0E-3;

        static const double INSIDE_TURN_VERTEX_SNAP_DISTANCE_FACTOR; // 1.0E-3;

        static const int MAX_CLOSING_SEG_FRACTION = 80;

        algorithm::LineIntersector li;

        double filletAngleQuantum;

        double maxCurveSegmentError;

        //
        OffsetCurveVertexList* vertexList;

        double distance;

        const geom::PrecisionModel* precisionModel;

        const BufferParameters& bufParams; 

        int closingSegFactor; // 1;

        geom::Coordinate s0, s1, s2;

        geom::LineSegment seg0;

        geom::LineSegment seg1;

        geom::LineSegment offset0;

        geom::LineSegment offset1;

        int side;

        // Not in JTS, used for single-sided buffers
        int endCapIndex;

        void init(double newDistance);

        static const double SIMPLIFY_FACTOR; // 100.0;

        double simplifyTolerance(double bufDistance);

        void computeLineBufferCurve(const geom::CoordinateSequence& inputPts);

        void computeRingBufferCurve(const geom::CoordinateSequence& inputPts,
                                    int side);

        void initSideSegments(const geom::Coordinate &nS1,
                              const geom::Coordinate &nS2, int nSide);

        void addNextSegment(const geom::Coordinate &p, bool addStartPoint);

        void addCollinear(bool addStartPoint);

        //
        void addOutsideTurn(int orientation, bool addStartPoint);

        //
        void addInsideTurn(int orientation, bool addStartPoint);

        void addLastSegment();

        void computeOffsetSegment(const geom::LineSegment& seg,
                                  int side, double distance,
                                  geom::LineSegment& offset);

        void addLineEndCap(const geom::Coordinate &p0,
                           const geom::Coordinate &p1);

        void addFillet(const geom::Coordinate &p, const geom::Coordinate &p0,
                       const geom::Coordinate &p1,
                       int direction, double radius);

        void addFillet(const geom::Coordinate &p, double startAngle,
                       double endAngle, int direction, double radius);

        void addCircle(const geom::Coordinate &p, double distance);

        void addSquare(const geom::Coordinate &p, double distance);

        std::vector<OffsetCurveVertexList*> vertexLists;
};

} // namespace geos::operation::buffer
} // namespace geos::operation
} // namespace geos

#endif // ndef GEOS_OP_BUFFER_OFFSETCURVEBUILDER_H

/**********************************************************************
 * $Log$
 * Revision 1.2  2006/03/27 17:04:17  strk
 * Cleanups and explicit initializations
 *
 * Revision 1.1  2006/03/14 00:19:40  strk
 * opBuffer.h split, streamlined headers in some (not all) files in operation/buffer/
 *
 **********************************************************************/

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