1 // Created on: 1993-10-20
2 // Created by: Bruno DUMORTIER
3 // Copyright (c) 1993-1999 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
18 #include <BSplCLib.hxx>
19 #include <Convert_CompBezierCurvesToBSplineCurve.hxx>
20 #include <gp.hxx>
21 #include <gp_Pnt.hxx>
22 #include <gp_Vec.hxx>
23 #include <PLib.hxx>
24 #include <Precision.hxx>
25 #include <Standard_ConstructionError.hxx>
26 #include <TColgp_HArray1OfPnt.hxx>
27
28 //=======================================================================
29 //function : Convert_CompBezierCurvesToBSplineCurve
30 //purpose :
31 //=======================================================================
32 Convert_CompBezierCurvesToBSplineCurve::
Convert_CompBezierCurvesToBSplineCurve(const Standard_Real AngularTolerance)33 Convert_CompBezierCurvesToBSplineCurve(
34 const Standard_Real AngularTolerance) :
35 myAngular(AngularTolerance),
36 myDone(Standard_False)
37 {
38 }
39
40
41 //=======================================================================
42 //function : AddCurve
43 //purpose :
44 //=======================================================================
45
AddCurve(const TColgp_Array1OfPnt & Poles)46 void Convert_CompBezierCurvesToBSplineCurve::AddCurve
47 (const TColgp_Array1OfPnt& Poles)
48 {
49 if ( !mySequence.IsEmpty()) {
50 gp_Pnt P1,P2;
51 P1 = mySequence.Last()->Value(mySequence.Last()->Upper());
52 P2 = Poles(Poles.Lower());
53
54 #ifdef OCCT_DEBUG
55 if (!P1.IsEqual(P2, Precision::Confusion()))
56 std::cout << "Convert_CompBezierCurvesToBSplineCurve::Addcurve" << std::endl;
57 #endif
58 }
59 myDone = Standard_False;
60 Handle(TColgp_HArray1OfPnt) HPoles =
61 new TColgp_HArray1OfPnt(Poles.Lower(),Poles.Upper());
62 HPoles->ChangeArray1() = Poles;
63 mySequence.Append(HPoles);
64 }
65
66
67 //=======================================================================
68 //function : Degree
69 //purpose :
70 //=======================================================================
71
Degree() const72 Standard_Integer Convert_CompBezierCurvesToBSplineCurve::Degree() const
73 {
74 return myDegree;
75 }
76
77
78 //=======================================================================
79 //function : NbPoles
80 //purpose :
81 //=======================================================================
82
NbPoles() const83 Standard_Integer Convert_CompBezierCurvesToBSplineCurve::NbPoles() const
84 {
85 return CurvePoles.Length();
86 }
87
88
89 //=======================================================================
90 //function : Poles
91 //purpose :
92 //=======================================================================
93
Poles(TColgp_Array1OfPnt & Poles) const94 void Convert_CompBezierCurvesToBSplineCurve::Poles
95 (TColgp_Array1OfPnt& Poles) const
96 {
97 Standard_Integer i, Lower = Poles.Lower(), Upper = Poles.Upper();
98 Standard_Integer k = 1;
99 for (i = Lower; i <= Upper; i++) {
100 Poles(i) = CurvePoles(k++);
101 }
102 }
103
104
105 //=======================================================================
106 //function : NbKnots
107 //purpose :
108 //=======================================================================
109
NbKnots() const110 Standard_Integer Convert_CompBezierCurvesToBSplineCurve::NbKnots() const
111 {
112 return CurveKnots.Length();
113 }
114
115
116 //=======================================================================
117 //function : KnotsAndMults
118 //purpose :
119 //=======================================================================
120
KnotsAndMults(TColStd_Array1OfReal & Knots,TColStd_Array1OfInteger & Mults) const121 void Convert_CompBezierCurvesToBSplineCurve::KnotsAndMults
122 (TColStd_Array1OfReal& Knots,
123 TColStd_Array1OfInteger& Mults ) const
124 {
125 Standard_Integer i, LowerK = Knots.Lower(), UpperK = Knots.Upper();
126 Standard_Integer LowerM = Mults.Lower(), UpperM = Mults.Upper();
127 Standard_Integer k = 1;
128 for (i = LowerK; i <= UpperK; i++) {
129 Knots(i) = CurveKnots(k++);
130 }
131 k = 1;
132 for (i = LowerM; i <= UpperM; i++) {
133 Mults(i) = KnotsMultiplicities(k++);
134 }
135 }
136
137
138
139 //=======================================================================
140 //function : Perform
141 //purpose :
142 //=======================================================================
143
Perform()144 void Convert_CompBezierCurvesToBSplineCurve::Perform()
145 {
146 myDone = Standard_True;
147 CurvePoles.Clear();
148 CurveKnots.Clear();
149 KnotsMultiplicities.Clear();
150 Standard_Integer LowerI = 1;
151 Standard_Integer UpperI = mySequence.Length();
152 Standard_Integer NbrCurv = UpperI-LowerI+1;
153 // Standard_Integer NbKnotsSpl = NbrCurv + 1 ;
154 TColStd_Array1OfReal CurveKnVals (1,NbrCurv);
155
156 Standard_Integer i;
157 myDegree = 0;
158 for ( i = 1; i <= mySequence.Length(); i++) {
159 myDegree = Max( myDegree, (mySequence(i))->Length() -1);
160 }
161
162 Standard_Real Det=0;
163 gp_Pnt P1, P2, P3;
164 Standard_Integer Deg, Inc, MaxDegree = myDegree;
165 TColgp_Array1OfPnt Points(1, myDegree+1);
166
167 for (i = LowerI ; i <= UpperI ; i++) {
168 // 1- Raise the Bezier curve to the maximum degree.
169 Deg = mySequence(i)->Length()-1;
170 Inc = myDegree - Deg;
171 if ( Inc > 0) {
172 BSplCLib::IncreaseDegree(myDegree,
173 mySequence(i)->Array1(), BSplCLib::NoWeights(),
174 Points, BSplCLib::NoWeights());
175 }
176 else {
177 Points = mySequence(i)->Array1();
178 }
179
180 // 2- Process the node of junction between 2 Bezier curves.
181 if (i == LowerI) {
182 // Processing of the initial node of the BSpline.
183 for (Standard_Integer j = 1 ; j <= MaxDegree ; j++) {
184 CurvePoles.Append(Points(j));
185 }
186 CurveKnVals(1) = 1.; // To begin the series.
187 KnotsMultiplicities.Append(MaxDegree+1);
188 Det = 1.;
189 }
190
191
192 if (i != LowerI) {
193 P2 = Points(1);
194 P3 = Points(2);
195 gp_Vec V1(P1, P2), V2(P2, P3);
196
197 // Processing of the tangency between Bezier and the previous.
198 // This allows to guarantee at least a C1 continuity if the tangents are
199 // coherent.
200
201 Standard_Real D1 = V1.SquareMagnitude();
202 Standard_Real D2 = V2.SquareMagnitude();
203 if (MaxDegree > 1 && //rln 20.06.99 work-around
204 D1 > gp::Resolution() && D2 > gp::Resolution() && V1.IsParallel(V2, myAngular ))
205 {
206 Standard_Real Lambda = Sqrt(D2/D1);
207 if(CurveKnVals(i-1) * Lambda > 10. * Epsilon(Det)) {
208 KnotsMultiplicities.Append(MaxDegree-1);
209 CurveKnVals(i) = CurveKnVals(i-1) * Lambda;
210 }
211 else {
212 CurvePoles.Append(Points(1));
213 KnotsMultiplicities.Append(MaxDegree);
214 CurveKnVals(i) = 1.0 ;
215 }
216 }
217 else {
218 CurvePoles.Append(Points(1));
219 KnotsMultiplicities.Append(MaxDegree);
220 CurveKnVals(i) = 1.0 ;
221 }
222 Det += CurveKnVals(i);
223
224 // Store the poles.
225 for (Standard_Integer j = 2 ; j <= MaxDegree ; j++) {
226 CurvePoles.Append(Points(j));
227 }
228
229 }
230
231
232 if (i == UpperI) {
233 // Processing of the end node of the BSpline.
234 CurvePoles.Append(Points(MaxDegree+1));
235 KnotsMultiplicities.Append(MaxDegree+1);
236 }
237 P1 = Points(MaxDegree);
238 }
239
240 // Correct nodal values to make them variable within [0.,1.].
241 CurveKnots.Append(0.0);
242 // std::cout << "Convert : Det = " << Det << std::endl;
243 for (i = 2 ; i <= NbrCurv ; i++) {
244 CurveKnots.Append(CurveKnots(i-1) + (CurveKnVals(i-1)/Det));
245 }
246 CurveKnots.Append(1.0);
247 }
248
249
250