include/geos/geom/LinearRing.h

   1 /**********************************************************************
   2  *
   3  * GEOS - Geometry Engine Open Source
   4  * http://geos.osgeo.org
   5  *
   6  * Copyright (C) 2001-2002 Vivid Solutions Inc.
   7  * Copyright (C) 2005 2006 Refractions Research Inc.
   8  *
   9  * This is free software; you can redistribute and/or modify it under
  10  * the terms of the GNU Lesser General Public Licence as published
  11  * by the Free Software Foundation.
  12  * See the COPYING file for more information.
  13  *
  14  **********************************************************************
  15  *
  16  * Last port: geom/LinearRing.java r320 (JTS-1.12)
  17  *
  18  **********************************************************************/
  19
  20 #ifndef GEOS_GEOS_LINEARRING_H
  21 #define GEOS_GEOS_LINEARRING_H
  22
  23 #include <geos/export.h>
  24 #include <string>
  25 #include <vector>
  26 #include <geos/platform.h>
  27 #include <geos/geom/LineString.h>
  28
  29 #include <geos/inline.h>
  30
  31 // Forward declarations
  32 namespace geos {
  33         namespace geom { // geos::geom
  34                 class Coordinate;
  35                 class CoordinateArraySequence;
  36         }
  37 }
  38
  39 namespace geos {
  40 namespace geom { // geos::geom
  41
  42 /**
  43  * \brief
  44  * Models an OGC SFS <code>LinearRing</code>.
  45  *
  46  * A LinearRing is a LineString which is both closed and simple.
  47  * In other words,
  48  * the first and last coordinate in the ring must be equal,
  49  * and the interior of the ring must not self-intersect.
  50  * Either orientation of the ring is allowed.
  51  *
  52  * A ring must have either 0 or 4 or more points.
  53  * The first and last points must be equal (in 2D).
  54  * If these conditions are not met, the constructors throw
  55  * an {@link IllegalArgumentException}
  56  */
  57 class GEOS_DLL LinearRing : public LineString {
  58
  59 public:
  60
  61         /**
  62          * The minimum number of vertices allowed in a valid non-empty ring (= 4).
  63          * Empty rings with 0 vertices are also valid.
  64          */
  65         static const unsigned int MINIMUM_VALID_SIZE = 4;
  66
  67         LinearRing(const LinearRing &lr);
  68
  69         /**
  70          * \brief Constructs a <code>LinearRing</code> with the given points.
  71          *
  72          * @param  points  points forming a closed and simple linestring, or
  73          *      <code>null</code> or an empty array to create the empty
  74          *      geometry.
  75          *      This array must not contain <code>null</code> elements.
  76          *      If not null LinearRing will take ownership of points.
  77          *
  78          * @param newFactory the GeometryFactory used to create this geometry
  79          *
  80          */
  81         LinearRing(CoordinateSequence* points,
  82                         const GeometryFactory *newFactory);
  83
  84         /// Hopefully cleaner version of the above
  85         LinearRing(CoordinateSequence::AutoPtr points,
  86                         const GeometryFactory *newFactory);
  87
  88         virtual Geometry *clone() const { return new LinearRing(*this); }
  89
  90         virtual ~LinearRing();
  91
  92         /** \brief
  93          * Returns <code>Dimension.FALSE</code>, since by definition
  94          * LinearRings do not have a boundary.
  95          *
  96          * @return Dimension::False
  97          */
  98         int getBoundaryDimension() const;
  99
 100         /** \brief
 101          * Returns <code>true</code>, since by definition LinearRings
 102          * are always simple.
 103          *
 104          * @return <code>true</code>
 105          *
 106          * @see Geometry::isSimple
 107          */
 108         bool isSimple() const;
 109
 110         bool isClosed() const;
 111
 112         std::string getGeometryType() const;
 113
 114         virtual GeometryTypeId getGeometryTypeId() const;
 115
 116         void setPoints(CoordinateSequence* cl);
 117
 118         Geometry* reverse() const;
 119
 120 private:
 121
 122         void validateConstruction();
 123 };
 124
 125
 126 } // namespace geos::geom
 127 } // namespace geos
 128
 129 //#ifdef GEOS_INLINE
 130 //# include "geos/geom/LinearRing.inl"
 131 //#endif
 132
 133 #endif // ndef GEOS_GEOS_LINEARRING_H
 134
 135 /**********************************************************************
 136  * $Log$
 137  * Revision 1.4  2006/04/11 11:16:25  strk
 138  * Added LineString and LinearRing constructors by auto_ptr
 139  *
 140  * Revision 1.3  2006/04/10 17:35:44  strk
 141  * Changed LineString::points and Point::coordinates to be wrapped
 142  * in an auto_ptr<>. This should close bugs #86 and #89
 143  *
 144  * Revision 1.2  2006/03/24 09:52:41  strk
 145  * USE_INLINE => GEOS_INLINE
 146  *
 147  * Revision 1.1  2006/03/09 16:46:49  strk
 148  * geos::geom namespace definition, first pass at headers split
 149  *
 150  **********************************************************************/