include/opencascade/Hermit.hxx

0001 // Created on: 1997-02-18
0002 // Created by: Stagiaire Francois DUMONT
0003 // Copyright (c) 1997-1999 Matra Datavision
0004 // Copyright (c) 1999-2014 OPEN CASCADE SAS
0005 //
0006 // This file is part of Open CASCADE Technology software library.
0007 //
0008 // This library is free software; you can redistribute it and/or modify it under
0009 // the terms of the GNU Lesser General Public License version 2.1 as published
0010 // by the Free Software Foundation, with special exception defined in the file
0011 // OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
0012 // distribution for complete text of the license and disclaimer of any warranty.
0013 //
0014 // Alternatively, this file may be used under the terms of Open CASCADE
0015 // commercial license or contractual agreement.
0016
0017 #ifndef _Hermit_HeaderFile
0018 #define _Hermit_HeaderFile
0019
0020 #include <Standard.hxx>
0021 #include <Standard_DefineAlloc.hxx>
0022 #include <Standard_Handle.hxx>
0023
0024 class Geom2d_BSplineCurve;
0025 class Geom_BSplineCurve;
0026
0027
0028 //! This  is used to  reparameterize Rational  BSpline
0029 //! Curves so that we can   concatenate them later to
0030 //! build C1 Curves  It builds and 1D-reparameterizing
0031 //! function starting from an Hermite interpolation and
0032 //! adding knots and modifying poles of the 1D BSpline
0033 //! obtained that way. The goal is to build a(u) so that
0034 //! if we consider a BSpline curve
0035 //! N(u)
0036 //! f(u) =  -----
0037 //! D(u)
0038 //!
0039 //! the function a(u)D(u) has value 1 at the umin and umax
0040 //! and has 0.0e0 derivative value a umin and umax.
0041 //! The details of the computation occurring in this package
0042 //! can be found by reading :
0043 //! " Etude sur la concatenation de NURBS en vue du
0044 //! balayage de surfaces" PFE n S85 Ensam Lille
0045 class Hermit
0046 {
0047 public:
0048
0049   DEFINE_STANDARD_ALLOC
0050
0051   //! returns the correct spline a(u) which will
0052   //! be multiplicated with BS later.
0053   Standard_EXPORT static Handle(Geom2d_BSplineCurve) Solution (const Handle(Geom_BSplineCurve)& BS, const Standard_Real TolPoles = 0.000001, const Standard_Real TolKnots = 0.000001);
0054
0055   //! returns the correct spline a(u) which will
0056   //! be multiplicated with BS later.
0057   Standard_EXPORT static Handle(Geom2d_BSplineCurve) Solution (const Handle(Geom2d_BSplineCurve)& BS, const Standard_Real TolPoles = 0.000001, const Standard_Real TolKnots = 0.000001);
0058
0059   //! returns the knots to insert to a(u) to
0060   //! stay with a constant sign and in the
0061   //! tolerances.
0062   Standard_EXPORT static void Solutionbis (const Handle(Geom_BSplineCurve)& BS, Standard_Real& Knotmin, Standard_Real& Knotmax, const Standard_Real TolPoles = 0.000001, const Standard_Real TolKnots = 0.000001);
0063
0064 };
0065
0066 #endif // _Hermit_HeaderFile