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.hxx> 21 #include <Standard_Type.hxx> 22 23 #include <Standard_Real.hxx> 24 #include <TColgp_Array1OfPnt2d.hxx> 25 #include <Standard_Transient.hxx> 26 #include <Standard_Integer.hxx> 27 class Standard_NullObject; 28 29 30 class Poly_Polygon2D; 31 DEFINE_STANDARD_HANDLE(Poly_Polygon2D, Standard_Transient) 32 33 //! Provides a polygon in 2D space (for example, in the 34 //! parametric space of a surface). It is generally an 35 //! approximate representation of a curve. 36 //! A Polygon2D is defined by a table of nodes. Each node is 37 //! a 2D point. If the polygon is closed, the point of closure is 38 //! repeated at the end of the table of nodes. 39 class Poly_Polygon2D : public Standard_Transient 40 { 41 42 public: 43 44 45 //! Constructs a 2D polygon defined by the table of points, <Nodes>. 46 Standard_EXPORT Poly_Polygon2D(const TColgp_Array1OfPnt2d& Nodes); 47 48 //! Returns the deflection of this polygon. 49 //! Deflection is used in cases where the polygon is an 50 //! approximate representation of a curve. Deflection 51 //! represents the maximum distance permitted between any 52 //! point on the curve and the corresponding point on the polygon. 53 //! By default the deflection value is equal to 0. An algorithm 54 //! using this 2D polygon with a deflection value equal to 0 55 //! considers that it is working with a true polygon and not with 56 //! an approximate representation of a curve. The Deflection 57 //! function is used to modify the deflection value of this polygon. 58 //! The deflection value can be used by any algorithm working with 2D polygons. 59 //! For example: 60 //! - An algorithm may use a unique deflection value for all 61 //! its polygons. In this case it is not necessary to use the 62 //! Deflection function. 63 //! - Or an algorithm may want to attach a different 64 //! deflection to each polygon. In this case, the Deflection 65 //! function is used to set a value on each polygon, and 66 //! later to fetch the value. 67 Standard_EXPORT Standard_Real Deflection() const; 68 69 //! Sets the deflection of this polygon to D 70 Standard_EXPORT void Deflection (const Standard_Real D); 71 72 //! Returns the number of nodes in this polygon. 73 //! Note: If the polygon is closed, the point of closure is 74 //! repeated at the end of its table of nodes. Thus, on a closed 75 //! triangle, the function NbNodes returns 4. 76 Standard_Integer NbNodes() const; 77 78 //! Returns the table of nodes for this polygon. 79 Standard_EXPORT const TColgp_Array1OfPnt2d& Nodes() const; 80 81 82 83 84 DEFINE_STANDARD_RTTIEXT(Poly_Polygon2D,Standard_Transient) 85 86 protected: 87 88 89 90 91 private: 92 93 94 Standard_Real myDeflection; 95 TColgp_Array1OfPnt2d myNodes; 96 97 98 }; 99 100 101 #include <Poly_Polygon2D.lxx> 102 103 104 105 106 107 #endif // _Poly_Polygon2D_HeaderFile 108