1 // Created on: 1997-05-28
2 // Created by: Xavier BENVENISTE
3 // Copyright (c) 1997-1999 Matra Datavision
4 // Copyright (c) 1999-2014 OPEN CASCADE SAS
6 // This file is part of Open CASCADE Technology software library.
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.
14 // Alternatively, this file may be used under the terms of Open CASCADE
15 // commercial license or contractual agreement.
17 #include <GeomLib_CheckBSplineCurve.ixx>
18 #include <Geom_BSplineCurve.hxx>
21 //=======================================================================
22 //function : GeomLib_CheckBSplineCurve
24 //=======================================================================
26 GeomLib_CheckBSplineCurve::GeomLib_CheckBSplineCurve(const Handle(Geom_BSplineCurve)& Curve,
27 const Standard_Real Tolerance,
28 const Standard_Real AngularTolerance)
30 myDone(Standard_False),
31 myFixFirstTangent(Standard_False),
32 myFixLastTangent(Standard_False),
33 myAngularTolerance(Abs(AngularTolerance)),
34 myTolerance(Abs(Tolerance)),
35 myFirstPole(1.0,0.0e0,0.e0),
36 myLastPole(1.0e0,0.0e0,0.e0)
42 Standard_Real tangent_magnitude,
47 num_poles = Curve->NbPoles() ;
48 if (( ! myCurve->IsPeriodic() )&& num_poles >= 4) {
53 for (ii = 1 ; ii <= 3 ; ii++) {
54 tangent.SetCoord(ii,myCurve->Pole(2).Coord(ii) - myCurve->Pole(1).Coord(ii)) ;
55 a_vector.SetCoord(ii, myCurve->Pole(3).Coord(ii) - myCurve->Pole(1).Coord(ii)) ;
57 tangent_magnitude = tangent.Magnitude() ;
58 vector_magnitude = a_vector.Magnitude() ;
59 if (tangent_magnitude > myTolerance &&
60 vector_magnitude > myTolerance)
62 value = tangent.Dot(a_vector) ;
64 for (ii = 1 ; ii <= 3 ; ii++) {
65 diff.SetCoord(ii, (tangent.Coord(ii) / tangent_magnitude) + (a_vector.Coord(ii) / vector_magnitude)) ;
69 if (angular_value < myAngularTolerance) {
70 myFixFirstTangent = Standard_True ;
72 if (tangent_magnitude > 0.5e0 * vector_magnitude) {
73 factor = 0.5e0 * vector_magnitude / tangent_magnitude ;
75 for (ii = 1 ; ii <= 3 ; ii++) {
76 myFirstPole.SetCoord(ii, myCurve->Pole(1).Coord(ii) - factor * tangent.Coord(ii)) ;
82 for (ii = 1 ; ii <= 3 ; ii++) {
83 tangent.SetCoord(ii,myCurve->Pole(num_poles-1).Coord(ii) - myCurve->Pole(num_poles).Coord(ii)) ;
84 a_vector.SetCoord(ii, myCurve->Pole(num_poles-2).Coord(ii) - myCurve->Pole(num_poles).Coord(ii)) ;
86 tangent_magnitude = tangent.Magnitude() ;
87 vector_magnitude = a_vector.Magnitude() ;
89 if (tangent_magnitude > myTolerance &&
90 vector_magnitude > myTolerance)
92 value = tangent.Dot(a_vector) ;
94 for (ii = 1 ; ii <= 3 ; ii++) {
95 diff.SetCoord(ii, (tangent.Coord(ii) / tangent_magnitude) + (a_vector.Coord(ii) / vector_magnitude)) ;
99 if ( angular_value < myAngularTolerance) {
100 myFixLastTangent = Standard_True ;
102 if (tangent_magnitude > 0.5e0 * vector_magnitude) {
103 factor = 0.5e0 * vector_magnitude / tangent_magnitude ;
105 for (ii = 1 ; ii <= 3 ; ii++) {
106 myLastPole.SetCoord(ii, myCurve->Pole(num_poles).Coord(ii) - factor * tangent.Coord(ii)) ;
115 myDone = Standard_True ;
119 //=======================================================================
120 //function : NeedTangentFix
122 //=======================================================================
124 void GeomLib_CheckBSplineCurve::NeedTangentFix(Standard_Boolean & FirstFlag,
125 Standard_Boolean & LastFlag) const
127 FirstFlag = myFixFirstTangent ;
128 LastFlag = myFixLastTangent ;
130 //=======================================================================
131 //function : FixTangent
133 //=======================================================================
135 Handle(Geom_BSplineCurve) GeomLib_CheckBSplineCurve::FixedTangent(const Standard_Boolean FirstFlag,
136 const Standard_Boolean LastFlag)
138 Handle(Geom_BSplineCurve) new_curve ;
139 if ((myFixFirstTangent && FirstFlag) ||(myFixLastTangent && LastFlag)) {
141 Handle(Geom_BSplineCurve)::DownCast(myCurve->Copy()) ;
144 if (myFixFirstTangent && FirstFlag) {
145 new_curve->SetPole(2,
148 if (myFixLastTangent && LastFlag) {
149 Standard_Integer num_poles = myCurve->NbPoles() ;
150 new_curve->SetPole(num_poles-1,
154 myDone = Standard_True ;
157 //=======================================================================
158 //function : FixTangent
160 //=======================================================================
162 void GeomLib_CheckBSplineCurve::FixTangent(const Standard_Boolean FirstFlag,
163 const Standard_Boolean LastFlag)
166 if (myFixFirstTangent && FirstFlag) {
170 if (myFixLastTangent && LastFlag) {
171 Standard_Integer num_poles = myCurve->NbPoles() ;
172 myCurve->SetPole(num_poles-1,
176 myDone = Standard_True ;