summaryrefslogtreecommitdiff
path: root/src/ShapeUpgrade/ShapeUpgrade_ConvertSurfaceToBezierBasis.cxx
blob: d238b02652bed07bc7c64ad0a1038e82c92db587 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
// File:	ShapeUpgrade_ConvertSurfaceToE3.cxx
// Created:	Fri May 21 15:08:31 1999
// Author:	Pavel DURANDIN
//		<pdn@friendox.nnov.matra-dtv.fr>

//   svv  10.01.00 porting on DEC

#include <ShapeUpgrade_ConvertSurfaceToBezierBasis.ixx>
#include <TColStd_HSequenceOfReal.hxx>
#include <Precision.hxx>
#include <Geom_RectangularTrimmedSurface.hxx>
#include <Geom_OffsetSurface.hxx>
#include <Geom_Plane.hxx>
#include <TColgp_Array2OfPnt.hxx>
#include <Geom_BezierSurface.hxx>
#include <TColStd_Array1OfReal.hxx>
#include <TColGeom_HArray2OfSurface.hxx>
#include <ShapeExtend.hxx>
#include <Geom_BSplineSurface.hxx>
#include <GeomConvert_BSplineSurfaceToBezierSurface.hxx>
#include <TColGeom_Array2OfBezierSurface.hxx>
#include <Geom_SurfaceOfRevolution.hxx>
#include <Geom_Curve.hxx>
#include <Geom_TrimmedCurve.hxx>
#include <TColGeom_HArray1OfCurve.hxx>
#include <Geom_OffsetCurve.hxx>
#include <ShapeUpgrade_ConvertCurve3dToBezier.hxx>
#include <Geom_SurfaceOfLinearExtrusion.hxx>
#include <Geom_BezierCurve.hxx>
#include <TColgp_Array1OfPnt.hxx>
#include <TColStd_HArray1OfReal.hxx>
#include <TColStd_Array1OfBoolean.hxx>


ShapeUpgrade_ConvertSurfaceToBezierBasis::ShapeUpgrade_ConvertSurfaceToBezierBasis()
{
  myPlaneMode      = Standard_True;
  myRevolutionMode = Standard_True;
  myExtrusionMode  = Standard_True;
  myBSplineMode    = Standard_True;
}

//=======================================================================
//function : Compute
//purpose  : 
//=======================================================================

void ShapeUpgrade_ConvertSurfaceToBezierBasis::Compute(const Standard_Boolean Segment)
{
  if(!Segment) {
    Standard_Real UF,UL,VF,VL;
    mySurface->Bounds(UF,UL,VF,VL);
    if(!Precision::IsInfinite(UF)) myUSplitValues->SetValue(1,UF);
    if(!Precision::IsInfinite(UL)) myUSplitValues->SetValue(myUSplitValues->Length(),UL);
    if(!Precision::IsInfinite(VF)) myVSplitValues->SetValue(1,VF);
    if(!Precision::IsInfinite(VL)) myVSplitValues->SetValue(myVSplitValues->Length(),VL);
  }
       
  Standard_Real UFirst = myUSplitValues->Value(1);
  Standard_Real ULast  = myUSplitValues->Value(myUSplitValues->Length());
  Standard_Real VFirst = myVSplitValues->Value(1);
  Standard_Real VLast  = myVSplitValues->Value(myVSplitValues->Length());
  Standard_Real precision = Precision::PConfusion();
  
  if (mySurface->IsKind(STANDARD_TYPE(Geom_RectangularTrimmedSurface))) {
    Handle(Geom_RectangularTrimmedSurface) Surface = Handle(Geom_RectangularTrimmedSurface)::DownCast(mySurface);
    Handle(Geom_Surface) BasSurf = Surface->BasisSurface();
    ShapeUpgrade_ConvertSurfaceToBezierBasis converter;
    converter.Init(BasSurf,UFirst,ULast,VFirst,VLast);
    converter.SetUSplitValues(myUSplitValues);
    converter.SetVSplitValues(myVSplitValues);
    converter.Compute(Standard_True);
    myUSplitValues->ChangeSequence() = converter.USplitValues()->Sequence();
    myVSplitValues->ChangeSequence() = converter.VSplitValues()->Sequence();
    myStatus |= converter.myStatus;
    mySegments = converter.Segments();
    return;
  } else if(mySurface->IsKind(STANDARD_TYPE(Geom_OffsetSurface))) {
    Handle(Geom_OffsetSurface) Offset = Handle(Geom_OffsetSurface)::DownCast(mySurface);
    Handle(Geom_Surface) BasSurf = Offset->BasisSurface();
    ShapeUpgrade_ConvertSurfaceToBezierBasis converter;
    converter.Init(BasSurf,UFirst,ULast,VFirst,VLast);
    converter.SetUSplitValues(myUSplitValues);
    converter.SetVSplitValues(myVSplitValues);
    converter.Compute(Standard_True);
    myUSplitValues->ChangeSequence() = converter.USplitValues()->Sequence();
    myVSplitValues->ChangeSequence() = converter.VSplitValues()->Sequence();
    myStatus |= converter.myStatus;
    mySegments = converter.Segments();
    return;
  } else if(mySurface->IsKind(STANDARD_TYPE(Geom_Plane))&&myPlaneMode) {
    Handle(Geom_Plane) pln = Handle(Geom_Plane)::DownCast(mySurface);
    TColgp_Array2OfPnt poles(1,2,1,2);
    gp_Pnt dp;
    poles(1,1) = dp = pln->Value(UFirst,VFirst); poles(1,2) = dp = pln->Value(UFirst,VLast);
    poles(2,1) = dp = pln->Value(ULast,VFirst);  poles(2,2) = dp = pln->Value(ULast,VLast);
    Handle(Geom_BezierSurface) bezier = new Geom_BezierSurface(poles);
    TColStd_Array1OfReal UJoints(1,2);
    UJoints(1) = UFirst; UJoints(2) = ULast;
    TColStd_Array1OfReal VJoints(1,2);
    VJoints(1) = VFirst; VJoints(2) = VLast;
    Handle(TColGeom_HArray2OfSurface) surf = new TColGeom_HArray2OfSurface(1,1,1,1);
    surf->SetValue(1,1,bezier);
    mySegments = new ShapeExtend_CompositeSurface(surf,UJoints,VJoints);
    myStatus = ShapeExtend::EncodeStatus ( ShapeExtend_DONE1 );
    return;
  } else if(mySurface->IsKind(STANDARD_TYPE(Geom_BezierSurface))) {
    Handle(Geom_BezierSurface) bezier = Handle(Geom_BezierSurface)::DownCast(mySurface);
    Handle(TColGeom_HArray2OfSurface) surf = new TColGeom_HArray2OfSurface(1,1,1,1);
    TColStd_Array1OfReal UJoints(1,2);
    UJoints(1) = UFirst; UJoints(2) = ULast;
    TColStd_Array1OfReal VJoints(1,2);
    VJoints(1) = VFirst; VJoints(2) = VLast;
    if(UFirst < precision && ULast > 1 - precision &&
       VFirst < precision && VLast > 1 - precision) {
      surf->SetValue(1,1,bezier);
      myStatus = ShapeExtend::EncodeStatus (ShapeExtend_OK);
    } else {
      Handle(Geom_BezierSurface) besNew = Handle(Geom_BezierSurface)::DownCast(bezier->Copy());
      //pdn K4L+ (work around)
      // Standard_Real u1 = 2*UFirst - 1;
      // Standard_Real u2 = 2*ULast - 1;
      // Standard_Real v1 = 2*VFirst - 1;
      // Standard_Real v2 = 2*VLast - 1;
      //rln C30 (direct use)
      Standard_Real u1 = UFirst;
      Standard_Real u2 = ULast;
      Standard_Real v1 = VFirst;
      Standard_Real v2 = VLast;
      besNew->Segment(u1,u2,v1,v2);
      surf->SetValue(1,1,besNew);
      myStatus = ShapeExtend::EncodeStatus (ShapeExtend_DONE2);
    }
    mySegments = new ShapeExtend_CompositeSurface(surf,UJoints,VJoints);
    return;
  } else if(mySurface->IsKind(STANDARD_TYPE(Geom_BSplineSurface))&&myBSplineMode) {
    Handle(Geom_BSplineSurface) bspline = Handle(Geom_BSplineSurface)::DownCast(mySurface);
    //pdn
    Standard_Real u1,u2,v1,v2;
    bspline->Bounds(u1,u2,v1,v2);
    GeomConvert_BSplineSurfaceToBezierSurface converter(bspline);//,UFirst,ULast,VFirst,VLast,precision;
    Standard_Integer nbUPatches = converter.NbUPatches();
    Standard_Integer nbVPatches = converter.NbVPatches();
    TColStd_Array1OfReal UJoints(1, nbUPatches+1);
    TColStd_Array1OfBoolean UReject(1, nbUPatches+1);
    UReject.Init(Standard_False);
    TColStd_Array1OfReal VJoints(1, nbVPatches+1);
    TColStd_Array1OfBoolean VReject(1, nbVPatches+1);
    VReject.Init(Standard_False);
    Standard_Integer NbUFiltered = 0;
    Standard_Integer NbVFiltered = 0;
    
    converter.UKnots(UJoints);
    TColStd_SequenceOfReal UFilteredJoints;
    UFilteredJoints.Append(UJoints(1));
    Standard_Integer i;
    for(i = 2; i <= nbUPatches+1; i++)
      if(UJoints(i)-UJoints(i-1) < precision) {
	NbUFiltered++;
	UReject(i-1) = Standard_True;
      }
      else
	UFilteredJoints.Append(UJoints(i));
    
    converter.VKnots(VJoints);
    TColStd_SequenceOfReal VFilteredJoints;
    VFilteredJoints.Append(VJoints(1));
    for( i = 2; i <= nbVPatches+1; i++)
      if(VJoints(i)-VJoints(i-1) < precision) {
	NbVFiltered++;
	VReject(i-1) = Standard_True;
      }
      else
	VFilteredJoints.Append(VJoints(i));

#ifdef DEB 
    if(NbVFiltered || NbUFiltered)
      cout<<"Warning: ShapeUpgrade_ConvertSurfaceToBezierBasis: thin patches dropped."<<endl;
#endif
    
    TColGeom_Array2OfBezierSurface Surfaces(1, nbUPatches, 1, nbVPatches);
    converter.Patches(Surfaces);
    Handle(TColGeom_HArray2OfSurface) srf = 
      new TColGeom_HArray2OfSurface(1,nbUPatches-NbUFiltered,1,nbVPatches-NbVFiltered);
    Standard_Integer indApp1 = 0;
    for(Standard_Integer ind1 = 1; ind1 <= nbUPatches; ind1++) {
      if(UReject(ind1)) continue;
      indApp1++;
      Standard_Integer indApp2 = 0;
      for(Standard_Integer ind2 = 1; ind2 <= nbVPatches; ind2++) {
	if(VReject(ind2)) continue;
	indApp2++;
	srf->SetValue(indApp1,indApp2,Surfaces(ind1,ind2));
      }
    }
    
    TColStd_Array1OfReal uj (1,UFilteredJoints.Length());
    for(i = 1; i <=UFilteredJoints.Length(); i++)
      uj(i) = UFilteredJoints.Value(i);
    
    TColStd_Array1OfReal vj (1,VFilteredJoints.Length());
    for(i = 1; i <=VFilteredJoints.Length(); i++)
      vj(i) = VFilteredJoints.Value(i);
    
    mySegments = new ShapeExtend_CompositeSurface(srf,uj,vj);
    
    Standard_Integer j; // svv #1
    for(j = 2; j <= myUSplitValues->Length(); j++) {
      ULast =  myUSplitValues->Value(j);
      for(Standard_Integer ii = 2; ii <= nbUPatches+1; ii++) {
	Standard_Real valknot = UJoints(ii);
	if(valknot-UFirst <=  precision) continue;
	if(ULast -valknot <=  precision) break;
	myUSplitValues->InsertBefore(j++,valknot);
      }
      UFirst = ULast;
    }
    for(j = 2; j <= myVSplitValues->Length(); j++) {
      VLast =  myVSplitValues->Value(j);
      for(Standard_Integer ii = 2; ii <= nbVPatches+1; ii++) {
	Standard_Real valknot = VJoints(ii);
	if(valknot-VFirst <= precision) continue;
	if(VLast -valknot <= precision) break;
	myVSplitValues->InsertBefore(j++,valknot);
      }
      VFirst = VLast;
    }
    myStatus = ShapeExtend::EncodeStatus (ShapeExtend_DONE1);
    return;
  } else if(mySurface->IsKind(STANDARD_TYPE(Geom_SurfaceOfRevolution))&&myRevolutionMode) {
    Handle(Geom_SurfaceOfRevolution) revol = Handle(Geom_SurfaceOfRevolution)::DownCast(mySurface);
    Handle(Geom_Curve) basis = revol->BasisCurve();
    if(basis->IsKind(STANDARD_TYPE(Geom_TrimmedCurve))) {
      Handle(Geom_TrimmedCurve) tc = Handle(Geom_TrimmedCurve)::DownCast(basis);
      basis = tc->BasisCurve();
    }
    Handle(TColGeom_HArray1OfCurve) curves;
    Standard_Integer nbCurves;
    Handle(TColStd_HSequenceOfReal) vPar = new TColStd_HSequenceOfReal;
    Handle(TColStd_HSequenceOfReal) vSVal= new TColStd_HSequenceOfReal;
    if(basis->IsKind(STANDARD_TYPE(Geom_OffsetCurve))) {
      Handle(Geom_OffsetCurve) offset = Handle(Geom_OffsetCurve)::DownCast(basis);
      Standard_Real value = offset->Offset();
      gp_Dir direction = offset->Direction();
      Handle(Geom_Curve) bas = offset->BasisCurve();
      ShapeUpgrade_ConvertCurve3dToBezier converter;
      converter.Init(bas,VFirst,VLast);
      converter.Perform(Standard_True);
      if(converter.Status(ShapeExtend_DONE)) 
	myStatus = ShapeExtend::EncodeStatus (ShapeExtend_DONE1);
      else
	myStatus = ShapeExtend::EncodeStatus (ShapeExtend_OK);
      
      vPar->ChangeSequence() = converter.SplitParams()->Sequence();
      vSVal->ChangeSequence()= converter.SplitValues()->Sequence();
      curves = converter.GetCurves();
      nbCurves = curves->Length();
      for(Standard_Integer i = 1; i <= nbCurves; i++) {
	Handle(Geom_OffsetCurve) offCur = new Geom_OffsetCurve(curves->Value(i),value,direction);
	curves->SetValue(i,offCur);
      }
    } else {
      ShapeUpgrade_ConvertCurve3dToBezier converter;
      converter.Init(basis,VFirst,VLast);
      converter.Perform(Standard_True);
      if(converter.Status(ShapeExtend_DONE)) 
	myStatus = ShapeExtend::EncodeStatus (ShapeExtend_DONE1);
      else
	myStatus = ShapeExtend::EncodeStatus (ShapeExtend_OK);

      vPar->ChangeSequence() = converter.SplitParams()->Sequence();
      vSVal->ChangeSequence()= converter.SplitValues()->Sequence();
      curves = converter.GetCurves();
      nbCurves = curves->Length();
    }
    
    gp_Ax1 axis = revol->Axis();
    Handle(TColGeom_HArray2OfSurface) surf = new TColGeom_HArray2OfSurface(1,1,1,nbCurves);
    Standard_Real Umin,Umax,Vmin,Vmax;
    mySurface->Bounds(Umin,Umax,Vmin,Vmax);
    Standard_Integer i; // svv #1
    for(i = 1; i <= nbCurves; i++) {
      Handle(Geom_SurfaceOfRevolution) rev = new Geom_SurfaceOfRevolution(curves->Value(i),axis);
      if( UFirst-Umin < Precision::PConfusion() &&
	 Umax-ULast < Precision::PConfusion() )
	surf->SetValue(1,i,rev);
      else {
	Handle(Geom_RectangularTrimmedSurface) rect = new Geom_RectangularTrimmedSurface(rev,UFirst,ULast,Standard_True);
	surf->SetValue(1,i,rect);
      }
    }
    TColStd_Array1OfReal UJoints(1, 2);
    TColStd_Array1OfReal VJoints(1, nbCurves+1);
    UJoints(1) = UFirst;  UJoints(2) = ULast;
    for(i = 1 ; i <= nbCurves+1; i++)
      VJoints(i) = vPar->Value(i);
    
    mySegments = new ShapeExtend_CompositeSurface(surf,UJoints,VJoints);
    
    for(Standard_Integer  j = 2; j <= myVSplitValues->Length(); j++) {
      VLast =  myVSplitValues->Value(j);
      for(Standard_Integer ii = 2; ii <= nbCurves+1; ii++) {
	Standard_Real valknot = vSVal->Value(ii);
	if(valknot-VFirst <= precision) continue;
	if(VLast -valknot <= precision) break;
	myVSplitValues->InsertBefore(j++,valknot);
      }
      VFirst = VLast;
    }
    return;
  } else if(mySurface->IsKind(STANDARD_TYPE(Geom_SurfaceOfLinearExtrusion))&&myExtrusionMode) {
    Handle(Geom_SurfaceOfLinearExtrusion) extr = Handle(Geom_SurfaceOfLinearExtrusion)::DownCast(mySurface);
    Handle(Geom_Curve) basis = extr->BasisCurve();
    //gp_Dir direction = extr->Direction(); // direction not used (skl)
    
    Handle(TColGeom_HArray1OfCurve) curves;
    Standard_Integer nbCurves;
    Handle(TColStd_HSequenceOfReal) uPar = new TColStd_HSequenceOfReal;
    Handle(TColStd_HSequenceOfReal) uSVal= new TColStd_HSequenceOfReal;
    ShapeUpgrade_ConvertCurve3dToBezier converter;
    converter.Init(basis,UFirst,ULast);
    converter.Perform(Standard_True);
    uPar->ChangeSequence() = converter.SplitParams()->Sequence();
    uSVal->ChangeSequence()= converter.SplitValues()->Sequence();
    curves = converter.GetCurves();
    nbCurves = curves->Length();
    
    gp_Trsf shiftF,shiftL;
    shiftF.SetTranslation(extr->Value(UFirst,0),extr->Value(UFirst,VFirst));
    shiftL.SetTranslation(extr->Value(UFirst,0),extr->Value(UFirst,VLast));
    Handle(TColGeom_HArray2OfSurface) surf = new TColGeom_HArray2OfSurface(1,nbCurves,1,1);
    
    Standard_Integer i; // svv #1
    for(i = 1; i <= nbCurves; i++) {
      Handle(Geom_BezierCurve) bez = Handle(Geom_BezierCurve)::DownCast(curves->Value(i));
      Standard_Integer nbPoles = bez->NbPoles();
      TColgp_Array1OfPnt poles(1,nbPoles);
      bez->Poles(poles);
      TColgp_Array2OfPnt resPoles(1,nbPoles,1,2);
      for(Standard_Integer j = 1; j <= nbPoles; j++) {
	resPoles(j,1) = poles(j).Transformed(shiftF);
	resPoles(j,2) = poles(j).Transformed(shiftL);
      }
      Handle(Geom_BezierSurface) bezier = new Geom_BezierSurface(resPoles);
      surf->SetValue(i,1,bezier);
    }
    
    TColStd_Array1OfReal UJoints(1, nbCurves+1);
    TColStd_Array1OfReal VJoints(1, 2);
    VJoints(1) = VFirst;  VJoints(2) = VLast;
    for(i = 1 ; i <= nbCurves+1; i++)
      UJoints(i) = uPar->Value(i);
    
    mySegments = new ShapeExtend_CompositeSurface(surf,UJoints,VJoints);
    
    for(Standard_Integer j = 2; j <= myUSplitValues->Length(); j++) {
      ULast =  myUSplitValues->Value(j);
      for(Standard_Integer ii = 2; ii <= nbCurves+1; ii++) {
	Standard_Real valknot = uSVal->Value(ii);
	if(valknot+UFirst <= precision) continue;
	if(ULast -valknot <= precision) break;
	myUSplitValues->InsertBefore(j++,valknot);
      }
      UFirst = ULast;
    }
    myStatus = ShapeExtend::EncodeStatus (ShapeExtend_DONE1);
    return;
  }
  else {
    TColStd_Array1OfReal UJoints(1,2);
    UJoints(1) = UFirst; UJoints(2) = ULast;
    TColStd_Array1OfReal VJoints(1,2);
    VJoints(1) = VFirst; VJoints(2) = VLast;
    Handle(TColGeom_HArray2OfSurface) surf = new TColGeom_HArray2OfSurface(1,1,1,1);
    Standard_Real U1,U2,V1,V2;
    mySurface->Bounds(U1,U2,V1,V2);
    Handle(Geom_Surface) S;
    if(U1-UFirst < precision && ULast - U2 < precision &&
       V2-VFirst < precision && VLast - V2 < precision)
      S = mySurface;
    else {
      Handle(Geom_RectangularTrimmedSurface) rts = new Geom_RectangularTrimmedSurface(mySurface,UFirst,ULast,VFirst,VLast);
      S = rts;
    }
    surf->SetValue(1,1,S);
    mySegments = new ShapeExtend_CompositeSurface(surf,UJoints,VJoints);
    myStatus = ShapeExtend::EncodeStatus (ShapeExtend_OK);
    return;
  }
}

//=======================================================================
//function : Build
//purpose  : 
//=======================================================================

static Handle(Geom_Surface) GetSegment(const Handle(Geom_Surface) surf,
				       const Standard_Real U1,
				       const Standard_Real U2,
				       const Standard_Real V1,
				       const Standard_Real V2)
{
  if(surf->IsKind(STANDARD_TYPE(Geom_BezierSurface))) {
    Handle(Geom_BezierSurface) bezier = Handle(Geom_BezierSurface)::DownCast(surf->Copy());
    Standard_Real prec = Precision::PConfusion();
    if(U1 < prec && U2 > 1-prec && V1 < prec && V2 > 1-prec)
      return bezier;
    //pdn K4L+ (work around)
    // Standard_Real u1 = 2*U1 - 1;
    // Standard_Real u2 = 2*U2 - 1;
    // Standard_Real v1 = 2*V1 - 1;
    // Standard_Real v2 = 2*V2 - 1; 
    //rln C30 (direct use)
    Standard_Real u1 = U1;
    Standard_Real u2 = U2;
    Standard_Real v1 = V1;
    Standard_Real v2 = V2;
    bezier->Segment(u1,u2,v1,v2);
    return bezier;
  }
  
  Handle(Geom_Surface) S;
  if(surf->IsKind(STANDARD_TYPE(Geom_RectangularTrimmedSurface))) {
    Handle(Geom_RectangularTrimmedSurface) rect = Handle(Geom_RectangularTrimmedSurface)::DownCast(surf);
    S = rect->BasisSurface();
  } else 
    S = surf;
  
  if(S->IsKind(STANDARD_TYPE(Geom_SurfaceOfRevolution))) {
    Handle(Geom_SurfaceOfRevolution) revol = Handle(Geom_SurfaceOfRevolution)::DownCast(S->Copy());
    Standard_Real Umin,Umax,Vmin,Vmax;
    revol->Bounds(Umin,Umax,Vmin,Vmax);
    Handle(Geom_Curve) basis = revol->BasisCurve();
    if(basis->IsKind(STANDARD_TYPE(Geom_OffsetCurve))) {
      Handle(Geom_OffsetCurve) offset = Handle(Geom_OffsetCurve)::DownCast(basis);
      basis = offset->BasisCurve();
    }
    if(basis->IsKind(STANDARD_TYPE(Geom_BezierCurve))) {
      Handle(Geom_BezierCurve) bezier = Handle(Geom_BezierCurve)::DownCast(basis);
      bezier->Segment(V1,V2);    
    }
    else {
#ifdef DEB
      cout <<"Warning: Resulting path is not surface of revolution basis on bezier curve"<<endl;
#endif
    }
    if(Abs(U1-Umin) < Precision::PConfusion() &&
       Abs(U2-Umax) < Precision::PConfusion() )
      return revol;
        
    Handle(Geom_RectangularTrimmedSurface) res = new Geom_RectangularTrimmedSurface(revol,U1,U2,Standard_True);
    return res;
  }
  else {
    Standard_Real Umin,Umax,Vmin,Vmax;
    surf->Bounds(Umin,Umax,Vmin,Vmax);
    if( U1-Umin < Precision::PConfusion() &&
        Umax-U2 < Precision::PConfusion() &&
        V1-Vmin < Precision::PConfusion() &&
        Vmax-V2 < Precision::PConfusion() )
      return surf;
    
    Handle(Geom_RectangularTrimmedSurface) res = new Geom_RectangularTrimmedSurface(surf,U1,U2,V1,V2);
    return res;
  }
}

//=======================================================================
//function : Build
//purpose  : 
//=======================================================================

void ShapeUpgrade_ConvertSurfaceToBezierBasis::Build(const Standard_Boolean /*Segment*/)
{
  Standard_Boolean isOffset = Standard_False;
  Standard_Real offsetValue=0;
  Handle(Geom_Surface) S;
  if (mySurface->IsKind(STANDARD_TYPE(Geom_RectangularTrimmedSurface))) {
    Handle(Geom_RectangularTrimmedSurface) Surface = Handle(Geom_RectangularTrimmedSurface)::DownCast(mySurface);
    S = Surface->BasisSurface();
  }
  else 
    S = mySurface;
  if(S->IsKind(STANDARD_TYPE(Geom_OffsetSurface))) {
    Handle(Geom_OffsetSurface) offSur = Handle(Geom_OffsetSurface)::DownCast(S);
    isOffset = Standard_True;
    offsetValue = offSur->Offset();
  }

  Standard_Real prec = Precision::PConfusion();
  Handle(TColStd_HArray1OfReal) myUSplitParams = mySegments->UJointValues();
  Handle(TColStd_HArray1OfReal) myVSplitParams = mySegments->VJointValues();
  Standard_Integer nbU = myUSplitValues->Length();
  Standard_Integer nbV = myVSplitValues->Length();
  
  Handle(TColGeom_HArray2OfSurface) resSurfaces = new TColGeom_HArray2OfSurface(1,nbU-1,1,nbV-1);
  Standard_Integer j1 = 2;
  for(Standard_Integer i1 = 2; i1 <= nbU; i1++) {
    Standard_Real parU = myUSplitValues->Value(i1);
    for(; j1<= myUSplitParams->Length(); j1++) {
      Standard_Real param = myUSplitParams->Value(j1);
      if(parU - param < prec)
	break;
    }
    
    Standard_Integer j2 = 2;
    for(Standard_Integer i2 = 2; i2 <= nbV; i2++) {
      Standard_Real parV = myVSplitValues->Value(i2);
      for(; j2<= myVSplitParams->Length(); j2++) 
	if(parV - myVSplitParams->Value(j2) < prec)
	  break;
      
      Handle(Geom_Surface) patch = mySegments->Patch(j1-1,j2-1);
      Standard_Real U1, U2, V1, V2;
      patch->Bounds(U1,U2,V1,V2);
      //linear recomputation of part:
      Standard_Real uFirst = myUSplitParams->Value(j1-1);
      Standard_Real uLast  = myUSplitParams->Value(j1);
      Standard_Real vFirst = myVSplitParams->Value(j2-1);
      Standard_Real vLast  = myVSplitParams->Value(j2);
      Standard_Real uFact = (U2-U1)/(uLast - uFirst);
      Standard_Real vFact = (V2-V1)/(vLast - vFirst);
      Standard_Real ppU = myUSplitValues->Value(i1-1);
      Standard_Real ppV = myVSplitValues->Value(i2-1);
      //defining a part
      Standard_Real uL1 = U1+(ppU - uFirst)*uFact;
      Standard_Real uL2 = U1+(parU- uFirst)*uFact;
      Standard_Real vL1 = V1+(ppV - vFirst)*vFact;
      Standard_Real vL2 = V1+(parV- vFirst)*vFact;
      Handle(Geom_Surface) res = GetSegment(patch,uL1, uL2, vL1, vL2);
      if(isOffset) {
	Handle(Geom_OffsetSurface) resOff = new Geom_OffsetSurface(res,offsetValue);
	res = resOff;
      }
      resSurfaces->SetValue(i1-1,i2-1,res);
    }
  }
  
  TColStd_Array1OfReal UJoints(1,nbU);
  Standard_Integer i; // svv #1
  for(i = 1; i <= nbU; i++)
    UJoints(i) = myUSplitValues->Value(i);
  
  TColStd_Array1OfReal VJoints(1,nbV);
  for(i = 1; i <= nbV; i++)
    VJoints(i) = myVSplitValues->Value(i);
      
  myResSurfaces = new ShapeExtend_CompositeSurface(resSurfaces,UJoints,VJoints);
}

//=======================================================================
//function : Segments
//purpose  : 
//=======================================================================

Handle(ShapeExtend_CompositeSurface) ShapeUpgrade_ConvertSurfaceToBezierBasis::Segments() const
{
  return mySegments;
}