1 // Created on: 1995-03-09
2 // Created by: Laurent PAINNOT
3 // Copyright (c) 1995-1999 Matra Datavision
4 // Copyright (c) 1999-2014 OPEN CASCADE SAS
5 //
6 // This file is part of Open CASCADE Technology software library.
7 //
8 // This library is free software; you can redistribute it and/or modify it under
9 // the terms of the GNU Lesser General Public License version 2.1 as published
10 // by the Free Software Foundation, with special exception defined in the file
11 // OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
12 // distribution for complete text of the license and disclaimer of any warranty.
13 //
14 // Alternatively, this file may be used under the terms of Open CASCADE
15 // commercial license or contractual agreement.
16 
17 #ifndef _Poly_Polygon2D_HeaderFile
18 #define _Poly_Polygon2D_HeaderFile
19 
20 #include <Standard_Type.hxx>
21 #include <TColgp_Array1OfPnt2d.hxx>
22 #include <Standard_Transient.hxx>
23 
24 DEFINE_STANDARD_HANDLE(Poly_Polygon2D, Standard_Transient)
25 
26 //! Provides a polygon in 2D space (for example, in the
27 //! parametric space of a surface). It is generally an
28 //! approximate representation of a curve.
29 //! A Polygon2D is defined by a table of nodes. Each node is
30 //! a 2D point. If the polygon is closed, the point of closure is
31 //! repeated at the end of the table of nodes.
32 class Poly_Polygon2D : public Standard_Transient
33 {
34 public:
35 
36   //! Constructs a 2D polygon with specified number of nodes.
37   Standard_EXPORT explicit Poly_Polygon2D (const Standard_Integer theNbNodes);
38 
39   //! Constructs a 2D polygon defined by the table of points, <Nodes>.
40   Standard_EXPORT Poly_Polygon2D(const TColgp_Array1OfPnt2d& Nodes);
41 
42   //! Returns the deflection of this polygon.
43   //! Deflection is used in cases where the polygon is an
44   //! approximate representation of a curve. Deflection
45   //! represents the maximum distance permitted between any
46   //! point on the curve and the corresponding point on the polygon.
47   //! By default the deflection value is equal to 0. An algorithm
48   //! using this 2D polygon with a deflection value equal to 0
49   //! considers that it is working with a true polygon and not with
50   //! an approximate representation of a curve. The Deflection
51   //! function is used to modify the deflection value of this polygon.
52   //! The deflection value can be used by any algorithm working  with 2D polygons.
53   //! For example:
54   //! -   An algorithm may use a unique deflection value for all
55   //! its polygons. In this case it is not necessary to use the
56   //! Deflection function.
57   //! -   Or an algorithm may want to attach a different
58   //! deflection to each polygon. In this case, the Deflection
59   //! function is used to set a value on each polygon, and
60   //! later to fetch the value.
Deflection() const61   Standard_Real Deflection() const { return myDeflection; }
62 
63   //! Sets the deflection of this polygon.
Deflection(const Standard_Real theDefl)64   void Deflection (const Standard_Real theDefl) { myDeflection = theDefl; }
65 
66   //! Returns the number of nodes in this polygon.
67   //! Note: If the polygon is closed, the point of closure is
68   //! repeated at the end of its table of nodes. Thus, on a closed
69   //! triangle, the function NbNodes returns 4.
NbNodes() const70   Standard_Integer NbNodes() const { return myNodes.Length(); }
71 
72   //! Returns the table of nodes for this polygon.
Nodes() const73   const TColgp_Array1OfPnt2d& Nodes() const { return myNodes; }
74 
75   //! Returns the table of nodes for this polygon.
ChangeNodes()76   TColgp_Array1OfPnt2d& ChangeNodes() { return myNodes; }
77 
78   //! Dumps the content of me into the stream
79   Standard_EXPORT virtual void DumpJson (Standard_OStream& theOStream, Standard_Integer theDepth = -1) const;
80 
81   DEFINE_STANDARD_RTTIEXT(Poly_Polygon2D,Standard_Transient)
82 
83 private:
84 
85   Standard_Real myDeflection;
86   TColgp_Array1OfPnt2d myNodes;
87 
88 };
89 
90 #endif // _Poly_Polygon2D_HeaderFile
91