OffsetCurveVertexList.h

00001 /**********************************************************************
00002  * $Id: OffsetCurveBuilder.h 1820 2006-09-06 16:54:23Z mloskot $
00003  *
00004  * GEOS - Geometry Engine Open Source
00005  * http://geos.refractions.net
00006  *
00007  * Copyright (C) 2007 Refractions Research Inc.
00008  *
00009  * This is free software; you can redistribute and/or modify it under
00010  * the terms of the GNU Lesser General Public Licence as published
00011  * by the Free Software Foundation. 
00012  * See the COPYING file for more information.
00013  *
00014  **********************************************************************
00015  *
00016  * Last port: operation/buffer/OffsetCurveVertexList.java rev. 1.1
00017  *
00018  **********************************************************************/
00019 
00020 #ifndef GEOS_OP_BUFFER_OFFSETCURVEVERTEXLIST_H
00021 #define GEOS_OP_BUFFER_OFFSETCURVEVERTEXLIST_H
00022 
00023 #include <geos/geom/Coordinate.h> // for inlines
00024 #include <geos/geom/CoordinateSequence.h> // for inlines
00025 #include <geos/geom/CoordinateArraySequence.h> // for composition
00026 #include <geos/geom/PrecisionModel.h> // for inlines
00027 
00028 #include <vector>
00029 #include <memory>
00030 
00031 // Forward declarations
00032 namespace geos {
00033         namespace geom {
00034                 //class CoordinateSequence;
00035                 //class PrecisionModel;
00036         }
00037 }
00038 
00039 namespace geos {
00040 namespace operation { // geos.operation
00041 namespace buffer { // geos.operation.buffer
00042 
00043 // ---------------------------------------------
00044 // OffsetCurveVertexList
00045 // ---------------------------------------------
00046 
00048 //
00051 class OffsetCurveVertexList 
00052 {
00053 
00054 private:
00055 
00056         geom::CoordinateSequence* ptList;
00057         bool ptListConsumed;
00058 
00059         const geom::PrecisionModel* precisionModel;
00060   
00067         double minimumVertexDistance;
00068 
00076         bool isDuplicate(const geom::Coordinate& pt)
00077         {
00078                 if (ptList->size() < 1)
00079                         return false;
00080                 const geom::Coordinate& lastPt = ptList->back();
00081                 double ptDist = pt.distance(lastPt);
00082                 if (ptDist < minimumVertexDistance)
00083                         return true;
00084                 return false;
00085         }
00086         
00087 
00088 public:
00089         
00090         OffsetCurveVertexList()
00091                 :
00092                 ptList(new geom::CoordinateArraySequence()),
00093                 ptListConsumed(false),
00094                 precisionModel(NULL),
00095                 minimumVertexDistance (0.0)
00096         {
00097         }
00098 
00099         ~OffsetCurveVertexList()
00100         {
00101                 if (!ptListConsumed)
00102                         delete ptList;
00103         }
00104         
00105         void setPrecisionModel(const geom::PrecisionModel* nPrecisionModel)
00106         {
00107                 precisionModel = nPrecisionModel;
00108         }
00109         
00110         void setMinimumVertexDistance(double nMinVertexDistance)
00111         {
00112                 minimumVertexDistance = nMinVertexDistance;
00113         }
00114         
00115         void addPt(const geom::Coordinate& pt)
00116         {
00117                 assert(precisionModel);
00118 
00119                 geom::Coordinate bufPt = pt;
00120                 precisionModel->makePrecise(bufPt);
00121                 // don't add duplicate (or near-duplicate) points
00122                 if (isDuplicate(bufPt))
00123                 {
00124                         return;
00125                 }
00126                 // we ask to allow repeated as we checked this ourself
00127                 // (JTS uses a vector for ptList, not a CoordinateSequence,
00128                 // we should do the same)
00129                 ptList->add(bufPt, true);
00130                 //ptList.push_back(bufPt);
00131         }
00132         
00133         // check that points are a ring - add the startpoint again if they are not
00134         void closeRing()
00135         {
00136                 if (ptList->size() < 1) return;
00137                 const geom::Coordinate& startPt = ptList->front();
00138                 const geom::Coordinate& lastPt = ptList->back();
00139                 if (startPt.equals(lastPt)) return;
00140                 // we ask to allow repeated as we checked this ourself
00141                 ptList->add(startPt, true);
00142         }
00143 
00144         geom::CoordinateSequence* getCoordinates()
00145         {
00146                 closeRing();
00147                 ptListConsumed = true;
00148                 return ptList;
00149         }
00150 
00151 };
00152 
00153 } // namespace geos.operation.buffer
00154 } // namespace geos.operation
00155 } // namespace geos
00156 
00157 
00158 #endif // ndef GEOS_OP_BUFFER_OFFSETCURVEVERTEXLIST_H
00159 
00160 /**********************************************************************
00161  * $Log$
00162  **********************************************************************/
00163 

Generated on Fri Mar 27 04:52:54 2009 for GEOS by  doxygen 1.5.4