1 // Copyright (c) 1999-2014 OPEN CASCADE SAS
2 //
3 // This file is part of Open CASCADE Technology software library.
4 //
5 // This library is free software; you can redistribute it and/or modify it under
6 // the terms of the GNU Lesser General Public License version 2.1 as published
7 // by the Free Software Foundation, with special exception defined in the file
8 // OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
9 // distribution for complete text of the license and disclaimer of any warranty.
10 //
11 // Alternatively, this file may be used under the terms of Open CASCADE
12 // commercial license or contractual agreement.
13 
14 
15 #include <Geom_BSplineCurve.hxx>
16 #include <Geom_Curve.hxx>
17 #include <ShapeAnalysis_Curve.hxx>
18 #include <ShapeCustom_Curve.hxx>
19 #include <TColgp_Array1OfPnt.hxx>
20 #include <TColStd_Array1OfInteger.hxx>
21 #include <TColStd_Array1OfReal.hxx>
22 
ShapeCustom_Curve()23 ShapeCustom_Curve::ShapeCustom_Curve()
24 {
25 }
26 
27 //=======================================================================
28 //function : ShapeCustom_Curve
29 //purpose  :
30 //=======================================================================
31 
ShapeCustom_Curve(const Handle (Geom_Curve)& C)32 ShapeCustom_Curve::ShapeCustom_Curve (const Handle(Geom_Curve)& C)
33 {
34   Init ( C );
35 }
36 
37 //=======================================================================
38 //function : Init
39 //purpose  :
40 //=======================================================================
41 
Init(const Handle (Geom_Curve)& C)42 void ShapeCustom_Curve::Init (const Handle(Geom_Curve)& C)
43 {
44   myCurve = C;
45 }
46 
47 //=======================================================================
48 //function : ConvertToPeriodic
49 //purpose  :
50 //=======================================================================
51 
Handle(Geom_Curve)52 Handle(Geom_Curve) ShapeCustom_Curve::ConvertToPeriodic (const Standard_Boolean substitute,
53                                                          const Standard_Real preci)
54 {
55   Handle(Geom_Curve) newCurve;
56   Handle(Geom_BSplineCurve) BSpl = Handle(Geom_BSplineCurve)::DownCast(myCurve);
57   if (BSpl.IsNull()) return newCurve;
58 
59   // PTV 13.02.02: check if curve closed with tolerance
60   Standard_Boolean closed = ShapeAnalysis_Curve::IsClosed(myCurve, preci);
61 
62   if ( ! closed ) return newCurve;
63 
64   Standard_Boolean converted = Standard_False; //:p6
65 
66   if ( closed && ! BSpl->IsPeriodic() && BSpl->NbPoles() >3 ) {
67     Standard_Boolean set = Standard_True;
68     // if degree+1 at ends, first change it to 1 by rearranging knots
69     if ( BSpl->Multiplicity(1) == BSpl->Degree() + 1 &&
70          BSpl->Multiplicity(BSpl->NbKnots()) == BSpl->Degree() + 1 ) {
71       Standard_Integer nbPoles = BSpl->NbPoles();
72       TColgp_Array1OfPnt oldPoles(1,nbPoles);
73       TColStd_Array1OfReal oldWeights(1,nbPoles);
74       Standard_Integer nbKnots = BSpl->NbKnots();
75       TColStd_Array1OfReal oldKnots(1,nbKnots);
76       TColStd_Array1OfInteger oldMults(1,nbKnots);
77 
78       BSpl->Poles(oldPoles);
79       BSpl->Weights(oldWeights);
80       BSpl->Knots(oldKnots);
81       BSpl->Multiplicities(oldMults);
82 
83       TColStd_Array1OfReal newKnots (1,nbKnots+2);
84       TColStd_Array1OfInteger newMults(1,nbKnots+2);
85       Standard_Real a = 0.5 * ( BSpl->Knot(2) - BSpl->Knot(1) +
86 			        BSpl->Knot(nbKnots) - BSpl->Knot(nbKnots-1) );
87 
88       newKnots(1) = oldKnots(1) - a;
89       newKnots(nbKnots+2) = oldKnots(nbKnots) + a;
90       newMults(1) = newMults(nbKnots+2) = 1;
91       for (Standard_Integer i = 2; i<=nbKnots+1; i++) {
92 	newKnots(i) = oldKnots(i-1);
93 	newMults(i) = oldMults(i-1);
94       }
95       newMults(2) = newMults(nbKnots+1) = BSpl->Degree();
96       Handle(Geom_BSplineCurve) res = new Geom_BSplineCurve(oldPoles, oldWeights,
97                                                             newKnots,newMults,
98                                                             BSpl->Degree(),BSpl->IsPeriodic());
99       BSpl = res;
100     }
101     else if ( BSpl->Multiplicity(1) > BSpl->Degree() ||
102 	      BSpl->Multiplicity(BSpl->NbKnots()) > BSpl->Degree() + 1 ) set = Standard_False;
103     if ( set ) {
104       BSpl->SetPeriodic(); // make periodic
105       converted = Standard_True;
106     }
107   }
108 #ifdef OCCT_DEBUG
109   std::cout << "Warning: ShapeCustom_Surface: Closed BSplineSurface is caused to be periodic" << std::endl;
110 #endif
111   if ( ! converted ) return newCurve;
112   newCurve = BSpl;
113   if ( substitute ) myCurve = newCurve;
114   return newCurve;
115 }
116