// Copyright (c) 1999-2014 OPEN CASCADE SAS
//
// This file is part of Open CASCADE Technology software library.
//
// This library is free software; you can redistribute it and/or modify it under
// the terms of the GNU Lesser General Public License version 2.1 as published
// by the Free Software Foundation, with special exception defined in the file
// OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
// distribution for complete text of the license and disclaimer of any warranty.
//
// Alternatively, this file may be used under the terms of Open CASCADE
// commercial license or contractual agreement.

//:j6 abv 7 Dec 98: ProSTEP TR10 r0601_id.stp #57676 & #58586: 
//    in FixIntersectingEdges, do not cut edges because of influence on adjacent faces
// pdn 17.12.98: shifting whole wire in FixShifted
//:k3 abv 24 Dec 98: BUC50070 #26682 and #30087: removing self-int loops on pcurves
// pdn 30.12.98: PRO10366 #210: shifting pcurve between two singularities
// pdn 05.01.98: renaming method FixLittle to FixSmall
//:l0 abv 10.01.99: remove unused code
//:n2 abv 22.01.99: ma-test5.igs: IGES read (pref3d): remove degen edge with no pcurve
//:o4 abv 17.02.99: r0301_db.stp #53082: using parameter isClosed in CheckOrder
//:p4 abv 23.02.99: PRO9234 #15720: update UV points of edges after shifting pcurves
//#67 rln 01.03.99 S4135: ims010.igs treatment of Geom_SphericalSurface together with V-closed surfaces
//:p7 abv 10.03.99 PRO18206: using method IsDegenerated() to detect singularity in FixLacking
//:r0 abv 19.03.99 PRO7226.stp #489490: remove degenerated edges if several
//#78 rln 12.03.99 S4135: checking spatial closure with Precision
//#79 rln 15.03.99 S4135: bmarkmdl.igs: check for gap before shifting on singularities
//    pdn 17.03.99 S4135: implemented fixing not adjacent intersection
//#86 rln 22.03.99 S4135: repeat of fix self-intersection if it was fixed just before
//%15 pdn 06.04.99 CTS18546-2: fix of self-intersection is repeated while fixed
//#3  smh 01.04.99 S4163: Overflow   
//#4  szv          S4163: optimization
//:r7 abv 12.04.99 S4136: FixLk: extend cases of adding degenerated edge
//:r8 abv 12.04.99 PRO10107.stp #2241: try increasing tolerance of edge for fix IE
//:s2 abv 21.04.99 S4136, PRO7978.igs: FixLacking extended to be able to bend pcurves
//szv#9:S4244:19Aug99 Methods FixGaps3d and FixGaps2d were introduced
//#15 smh 03.04.2000 PRO19800. Checking degenerated point on a surface of revolution.
// sln 25.09.2001  checking order of 3d and 2d representation curves  
// van 19.10.2001  fix of non-adjacent self-intersection corrected to agree with BRepCheck
// skl 07.03.2002 fix for bug OCC180
// skl 15.05.2002 for OCC208 (if few edges have reference to 
//                one pcurve we make replace pcurve)
// PTV 26.06.2002  Remove regressions after fix OCC450

#include <ShapeFix_Wire.hxx>

#include <BRep_Builder.hxx>
#include <BRep_GCurve.hxx>
#include <BRep_TEdge.hxx>
#include <BRep_Tool.hxx>
#include <BRepBuilderAPI_MakeEdge.hxx>
#include <BRepBuilderAPI_MakeVertex.hxx>
#include <BRepTools.hxx>
#include <Geom2d_Curve.hxx>
#include <Geom2d_Line.hxx>
#include <Geom2d_TrimmedCurve.hxx>
#include <Geom2dAdaptor_Curve.hxx>
#include <Geom2dConvert.hxx>
#include <Geom_BSplineCurve.hxx>
#include <Geom_Curve.hxx>
#include <Geom_OffsetCurve.hxx>
#include <Geom_Plane.hxx>
#include <Geom_SphericalSurface.hxx>
#include <Geom_Surface.hxx>
#include <Geom_SurfaceOfRevolution.hxx>
#include <Geom_TrimmedCurve.hxx>
#include <GeomAdaptor_Curve.hxx>
#include <GeomAPI.hxx>
#include <GeomAPI_ProjectPointOnCurve.hxx>
#include <GeomConvert_CompCurveToBSplineCurve.hxx>
#include <IntRes2d_IntersectionPoint.hxx>
#include <IntRes2d_SequenceOfIntersectionPoint.hxx>
#include <Message_Msg.hxx>
#include <Precision.hxx>
#include <ShapeAnalysis.hxx>
#include <ShapeAnalysis_Curve.hxx>
#include <ShapeAnalysis_Edge.hxx>
#include <ShapeAnalysis_Surface.hxx>
#include <ShapeAnalysis_TransferParametersProj.hxx>
#include <ShapeAnalysis_Wire.hxx>
#include <ShapeAnalysis_WireOrder.hxx>
#include <ShapeBuild_Edge.hxx>
#include <ShapeBuild_ReShape.hxx>
#include <ShapeBuild_Vertex.hxx>
#include <ShapeConstruct_ProjectCurveOnSurface.hxx>
#include <ShapeExtend.hxx>
#include <ShapeExtend_WireData.hxx>
#include <ShapeFix_Edge.hxx>
#include <ShapeFix_IntersectionTool.hxx>
#include <ShapeFix_SplitTool.hxx>
#include <Standard_ErrorHandler.hxx>
#include <Standard_Failure.hxx>
#include <Standard_Type.hxx>
#include <TColgp_Array1OfPnt.hxx>
#include <TColgp_SequenceOfPnt.hxx>
#include <TColStd_Array1OfInteger.hxx>
#include <TColStd_Array1OfReal.hxx>
#include <TColStd_HSequenceOfReal.hxx>
#include <TopExp_Explorer.hxx>
#include <TopLoc_Location.hxx>
#include <TopoDS.hxx>
#include <TopoDS_Edge.hxx>
#include <TopoDS_Face.hxx>
#include <TopoDS_Vertex.hxx>
#include <TopoDS_Wire.hxx>
#include <TopTools_Array1OfShape.hxx>
#include <TopTools_HSequenceOfShape.hxx>

IMPLEMENT_STANDARD_RTTIEXT(ShapeFix_Wire,ShapeFix_Root)

//S4135
//#######################################################################
//  Constructors, initializations, modes, querying
//#######################################################################
//=======================================================================
//function : ShapeFix_Wire
//purpose  : 
//=======================================================================
ShapeFix_Wire::ShapeFix_Wire() : myMaxTailAngleSine(0), myMaxTailWidth(-1)
{
  myFixEdge = new ShapeFix_Edge;
  myAnalyzer = new ShapeAnalysis_Wire;
  ClearModes();
  ClearStatuses();
  myStatusRemovedSegment = Standard_False;
}

//=======================================================================
//function : ShapeFix_Wire
//purpose  : 
//=======================================================================

ShapeFix_Wire::ShapeFix_Wire (
  const TopoDS_Wire& wire,
  const TopoDS_Face &face,
  const Standard_Real prec) : myMaxTailAngleSine(0), myMaxTailWidth(-1)
{
  myFixEdge = new ShapeFix_Edge;
  myAnalyzer = new ShapeAnalysis_Wire;
  ClearModes();
  SetMaxTolerance ( prec );
  myStatusRemovedSegment = Standard_False;
  Init ( wire, face, prec );
}

//=======================================================================
//function : SetPrecision
//purpose  : 
//=======================================================================

void ShapeFix_Wire::SetPrecision (const Standard_Real prec) 
{
  ShapeFix_Root::SetPrecision ( prec );
  myAnalyzer->SetPrecision ( prec );
}
 
//=======================================================================
//function : SetMaxTailAngle
//purpose  :
//=======================================================================
void ShapeFix_Wire::SetMaxTailAngle(const Standard_Real theMaxTailAngle)
{
  myMaxTailAngleSine = Sin(theMaxTailAngle);
  myMaxTailAngleSine = (myMaxTailAngleSine >= 0) ? myMaxTailAngleSine : 0;
}

//=======================================================================
//function : SetMaxTailWidth
//purpose  :
//=======================================================================
void ShapeFix_Wire::SetMaxTailWidth(const Standard_Real theMaxTailWidth)
{
  myMaxTailWidth = theMaxTailWidth;
}

//=======================================================================
//function : ClearModes
//purpose  : 
//=======================================================================

void ShapeFix_Wire::ClearModes()
{
  myTopoMode = Standard_False;
  myGeomMode = Standard_True;
  myClosedMode = Standard_True;
  myPreference2d = Standard_True;
  myFixGapsByRanges = Standard_False;

  myRemoveLoopMode = -1;

  myFixReversed2dMode = -1;
  myFixRemovePCurveMode = -1;
  myFixRemoveCurve3dMode = -1;
  myFixAddPCurveMode = -1;
  myFixAddCurve3dMode = -1;
  myFixSeamMode = -1;
  myFixShiftedMode = -1;
  myFixSameParameterMode = -1;
  myFixVertexToleranceMode = -1;

  myFixNotchedEdgesMode = -1;
  myFixSelfIntersectingEdgeMode = -1;
  myFixIntersectingEdgesMode = -1;
  myFixNonAdjacentIntersectingEdgesMode = -1;
  myFixTailMode = 0;

  myFixReorderMode = -1;
  myFixSmallMode = -1;
  myFixConnectedMode = -1;
  myFixEdgeCurvesMode = -1;
  myFixDegeneratedMode = -1;
  myFixSelfIntersectionMode = -1;
  myFixLackingMode = -1;
  myFixGaps3dMode = -1;
  myFixGaps2dMode = -1;
}

//=======================================================================
//function : ClearStatuses
//purpose  : 
//=======================================================================

void ShapeFix_Wire::ClearStatuses()
{
  Standard_Integer emptyStatus = ShapeExtend::EncodeStatus ( ShapeExtend_OK );

  myLastFixStatus          = emptyStatus;

  myStatusReorder          = emptyStatus;
  myStatusSmall            = emptyStatus;
  myStatusConnected        = emptyStatus;
  myStatusEdgeCurves       = emptyStatus;
  myStatusDegenerated      = emptyStatus;
  myStatusSelfIntersection = emptyStatus;
  myStatusLacking          = emptyStatus;
  myStatusGaps3d           = emptyStatus; //szv#9:S4244:19Aug99 new method introduced
  myStatusGaps2d           = emptyStatus; //szv#9:S4244:19Aug99 new method introduced
  myStatusClosed           = emptyStatus;
  myStatusNotches = emptyStatus;
  myStatusFixTails = emptyStatus;
}

//=======================================================================
//function : Init
//purpose  : 
//=======================================================================

void ShapeFix_Wire::Init (const TopoDS_Wire& wire, 
			  const TopoDS_Face &face, const Standard_Real prec) 
{
  Load ( wire );
  SetFace ( face );
  SetPrecision ( prec );
}

//=======================================================================
//function : Init
//purpose  : 
//=======================================================================

void ShapeFix_Wire::Init (const Handle(ShapeAnalysis_Wire)& saw) 
{
  ClearStatuses();
  myAnalyzer = saw;
  myShape.Nullify();
//  SetPrecision ( saw.Precision() );
}

//=======================================================================
//function : Load
//purpose  : 
//=======================================================================

void ShapeFix_Wire::Load (const TopoDS_Wire& wire) 
{
  ClearStatuses();

  TopoDS_Wire W = wire;
  if ( ! Context().IsNull() ) {
    TopoDS_Shape S = Context()->Apply ( wire );
    W = TopoDS::Wire ( S );
  }

  myAnalyzer->Load ( W );
  myShape = wire;
}

//=======================================================================
//function : Load
//purpose  : 
//=======================================================================

void ShapeFix_Wire::Load (const Handle(ShapeExtend_WireData)& sbwd) 
{
  ClearStatuses();
  myAnalyzer->Load ( sbwd );
  if ( ! Context().IsNull() ) UpdateWire();
  myShape.Nullify();
}

//=======================================================================
//function : NbEdges
//purpose  : 
//=======================================================================

Standard_Integer ShapeFix_Wire::NbEdges() const
{
  Handle(ShapeExtend_WireData) sbwd = myAnalyzer->WireData();
  return sbwd.IsNull() ? 0 : sbwd->NbEdges();
}

//#######################################################################
//  Fixing methods of API level
//#######################################################################
  
//=======================================================================
//function : Perform
//purpose  : This method performs all the available fixes.
//           If some fix is turned on or off explicitly by the flag,
//           it is called or not depending on that flag
//           Else (i.e. if flag is default) fix is called depending on the 
//           situation: default is True, but some fixes are not called or
//           are limited if order of edges in the wire is not OK
//=======================================================================

Standard_Boolean ShapeFix_Wire::Perform() 
{
  ClearStatuses();
  if ( ! IsLoaded() ) return Standard_False;

  if ( !Context().IsNull() )
    myFixEdge->SetContext( Context() );

  Standard_Boolean Fixed = Standard_False;
  
  // FixReorder is first, because as a rule wire is required to be ordered
  // We shall analyze the order of edges in the wire and set appropriate 
  // status even if FixReorder should not be called (if it is forbidden)

  ShapeAnalysis_WireOrder sawo;
  Standard_Boolean ReorderOK = (myAnalyzer->CheckOrder( sawo, myClosedMode ) == 0 );
  if ( NeedFix ( myFixReorderMode, ! ReorderOK ) ) { 
    if(FixReorder()) Fixed = Standard_True; 
    ReorderOK = ! StatusReorder ( ShapeExtend_FAIL );
  }

  // FixSmall is allowed to change topology only if mode is set and FixReorder 
  // did not failed
  if ( NeedFix ( myFixSmallMode, myTopoMode ) ) {
    if ( FixSmall ( ! myTopoMode || ! ReorderOK, MinTolerance() ) ) {
      Fixed = Standard_True;
      // retry reorder if necessary (after FixSmall it can work better)
      if ( NeedFix ( myFixReorderMode, ! ReorderOK ) ) { 
	FixReorder();
	ReorderOK = ! StatusReorder ( ShapeExtend_FAIL );
      }
    }
  }

  if ( NeedFix ( myFixConnectedMode, ReorderOK ) ) {
    if ( FixConnected() ) Fixed = Standard_True;
  }

  if ( NeedFix ( myFixEdgeCurvesMode ) ) {
    Standard_Integer savFixShiftedMode = myFixShiftedMode;
    // turn out FixShifted if reorder not done
    if ( myFixShiftedMode == -1 && ! ReorderOK ) myFixShiftedMode = 0; 
    if ( FixEdgeCurves() ) Fixed = Standard_True;
    myFixShiftedMode = savFixShiftedMode;
  }
  
  if ( NeedFix ( myFixDegeneratedMode ) ) {
    if ( FixDegenerated() ) Fixed = Standard_True; // ?? if ! ReorderOK ??
  }
  
  //pdn - temporary to test
  if (myFixTailMode <= 0 && NeedFix(myFixNotchedEdgesMode, ReorderOK))
  {
    Fixed |= FixNotchedEdges();
    if(Fixed) FixShifted(); //skl 07.03.2002 for OCC180
  }
    
  if (myFixTailMode != 0)
  {
    if (FixTails())
    {
      Fixed =Standard_True;
      FixShifted();
    }
  }

  if ( NeedFix ( myFixSelfIntersectionMode, myClosedMode ) ) {
    Standard_Integer savFixIntersectingEdgesMode = myFixIntersectingEdgesMode;
    // switch off FixIntEdges if reorder not done
    if ( myFixIntersectingEdgesMode == -1 && ! ReorderOK ) 
         myFixIntersectingEdgesMode = 0; 
    if ( FixSelfIntersection() ) Fixed = Standard_True;
    FixReorder();
    myFixIntersectingEdgesMode = savFixIntersectingEdgesMode;
  }

  if ( NeedFix ( myFixLackingMode, ReorderOK ) ) {
    if ( FixLacking() ) Fixed = Standard_True;
  }

  // TEMPORARILY without special mode !!!
  Handle(ShapeExtend_WireData) sbwd = WireData();
  for (Standard_Integer iedge = 1; iedge <= sbwd->NbEdges(); iedge++)
    if ( myFixEdge->FixVertexTolerance (sbwd->Edge (iedge), Face()) ) 
    {
      Fixed = Standard_True;
    }

  if (  !Context().IsNull() )
    UpdateWire();

  return Fixed;
}

//=======================================================================
//function : FixReorder
//purpose  : 
//=======================================================================

Standard_Boolean ShapeFix_Wire::FixReorder(Standard_Boolean theModeBoth)
{
  myStatusReorder = ShapeExtend::EncodeStatus(ShapeExtend_OK);
  if (!IsLoaded())
  {
    return Standard_False;
  }

  // fix in Both mode for bi-periodic surface
  ShapeAnalysis_WireOrder sawo;
  if (!myAnalyzer->Surface().IsNull() &&
      myAnalyzer->Surface()->Surface()->IsUPeriodic() &&
      myAnalyzer->Surface()->Surface()->IsVPeriodic() &&
      theModeBoth)
  {
    myAnalyzer->CheckOrder(sawo, myClosedMode, Standard_True, Standard_True);
  }
  else
  {
    myAnalyzer->CheckOrder(sawo, myClosedMode, Standard_True, Standard_False);
  }

  FixReorder(sawo);

  if (LastFixStatus(ShapeExtend_FAIL))
  {
    myStatusReorder |= ShapeExtend::EncodeStatus(LastFixStatus(ShapeExtend_FAIL1) ? ShapeExtend_FAIL1 : ShapeExtend_FAIL2);
  }
  if (!LastFixStatus(ShapeExtend_DONE))
  {
    return Standard_False;
  }

  myStatusReorder |= ShapeExtend::EncodeStatus(ShapeExtend_DONE1);
  if (sawo.Status() == 2 || sawo.Status() == -2)
  {
    myStatusReorder |= ShapeExtend::EncodeStatus(ShapeExtend_DONE2);
  }
  if (sawo.Status() < 0)
  {
    myStatusReorder |= ShapeExtend::EncodeStatus(ShapeExtend_DONE3);
  }
  if (sawo.Status() == 3)
  {
    // only shifted
    myStatusReorder |= ShapeExtend::EncodeStatus(ShapeExtend_DONE5);
  }
  return Standard_True;
}

//=======================================================================
//function : FixSmall
//purpose  : 
//=======================================================================

Standard_Integer ShapeFix_Wire::FixSmall (const Standard_Boolean lockvtx,
					     const Standard_Real precsmall) 
{
  myStatusSmall = ShapeExtend::EncodeStatus ( ShapeExtend_OK );
  if ( ! IsLoaded() ) return Standard_False;
  
  for ( Standard_Integer i = NbEdges(); i >0; i-- ) {
    FixSmall ( i, lockvtx, precsmall );
    myStatusSmall |= myLastFixStatus;
  }

  return StatusSmall ( ShapeExtend_DONE );

}

//=======================================================================
//function : FixConnected
//purpose  : 
//=======================================================================

Standard_Boolean ShapeFix_Wire::FixConnected (const Standard_Real prec) 
{
  myStatusConnected = ShapeExtend::EncodeStatus ( ShapeExtend_OK );
  if ( ! IsLoaded() ) return Standard_False;
  
  Standard_Integer stop = ( myClosedMode ? 0 : 1 );
  for ( Standard_Integer i = NbEdges(); i > stop; i-- ) {
    FixConnected ( i, prec );
    myStatusConnected |= myLastFixStatus;
  }

  return StatusConnected ( ShapeExtend_DONE );
}

//=======================================================================
//function : FixEdgeCurves
//purpose  : 
//=======================================================================

Standard_Boolean ShapeFix_Wire::FixEdgeCurves() 
{
  myStatusEdgeCurves = ShapeExtend::EncodeStatus ( ShapeExtend_OK );
  if ( ! IsLoaded() ) return Standard_False;
  Standard_Boolean isReady = IsReady();

  Handle(ShapeExtend_WireData) sbwd = WireData();
  Standard_Integer i, nb = sbwd->NbEdges();
  TopoDS_Face face = Face();
  Handle(ShapeFix_Edge) theAdvFixEdge = myFixEdge;
  if (theAdvFixEdge.IsNull()) myFixReversed2dMode = Standard_False;

  // fix revesred 2d / 3d curves
  if ( isReady && NeedFix ( myFixReversed2dMode ) ) {
    for ( i=1; i <= nb; i++ ) {
      theAdvFixEdge->FixReversed2d ( sbwd->Edge(i), face ); 
      if ( theAdvFixEdge->Status ( ShapeExtend_DONE ) ) 
	myStatusEdgeCurves |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE1 );
      if ( theAdvFixEdge->Status ( ShapeExtend_FAIL ) ) 
	myStatusEdgeCurves |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL1 );
    }
  }
  
  // add / remove pcurve
  if ( isReady && NeedFix ( myFixRemovePCurveMode, Standard_False ) ) {
    for ( i=1; i <= nb; i++ ) {
      myFixEdge->FixRemovePCurve ( sbwd->Edge(i), face );
      if ( myFixEdge->Status ( ShapeExtend_DONE ) ) 
	myStatusEdgeCurves |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE2 );
      if ( myFixEdge->Status ( ShapeExtend_FAIL ) ) 
	myStatusEdgeCurves |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL2 );
    }
  }

  if ( isReady && NeedFix ( myFixAddPCurveMode ) ) {
    Standard_Integer overdegen = 0; //:c0
    for ( i=1; i <= nb; i++ ) {
      myFixEdge->FixAddPCurve ( sbwd->Edge(i), face, sbwd->IsSeam(i), 
			 myAnalyzer->Surface(), Precision() );
      if ( myFixEdge->Status ( ShapeExtend_DONE ) ) 
	myStatusEdgeCurves |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE3 );
      if ( myFixEdge->Status ( ShapeExtend_FAIL ) ) 
	myStatusEdgeCurves |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL3 );

      //if ( !sbwd->IsSeam(i) && myFixEdge->Status ( ShapeExtend_DONE2 )
      //     && BRep_Tool::SameParameter(sbwd->Edge(i)) ) {
      if ( !sbwd->IsSeam(i) && myFixEdge->Status ( ShapeExtend_DONE2 ) ) {
	// abv 24 Feb 00: trj3_s1-ac-214.stp #1631 etc.: try to split the edge in singularity
	if ( ! Context().IsNull() ) { 
	  ShapeBuild_Edge sbe;
	  TopoDS_Edge E = sbwd->Edge ( i );
	  ShapeAnalysis_Curve SAC;
	  Standard_Real a, b;
	  Handle(Geom_Curve) C = BRep_Tool::Curve ( E, a, b );
	  Handle(ShapeAnalysis_Surface) S = myAnalyzer->Surface();
	  Standard_Integer nbs = S->NbSingularities(MinTolerance());
	  GeomAdaptor_Curve GAC ( C, a, b );
	  TColStd_SequenceOfReal seq;
	  for (Standard_Integer j=1; j <= nbs; j++) {
	    Standard_Real Preci;
	    gp_Pnt2d pd1, pd2;
	    gp_Pnt P3d, pr;
	    Standard_Real par1, par2, split;
	    Standard_Boolean tmpUIsoDeg;
	    S->Singularity (j, Preci, P3d, pd1, pd2, par1, par2, tmpUIsoDeg);
	    if ( SAC.Project ( GAC, P3d, MinTolerance(), pr, split, Standard_True ) < Max(Preci,MinTolerance()) ) {
	      if ( split - a > ::Precision::PConfusion() &&
		   b - split > ::Precision::PConfusion() ) {
		Standard_Integer k;
		for ( k=1; k <= seq.Length(); k++ ) {
		  if ( split < seq(k)-::Precision::PConfusion() ) {
		    seq.InsertBefore ( k, split );
		    break;
		  }
		  else if ( split < seq(k)+::Precision::PConfusion() ) break;
		}
		if ( k > seq.Length() ) seq.Append ( split );
	      }
	    }
	  }
	  if ( seq.Length() >0 ) { // supposed that edge is SP
#ifdef OCCT_DEBUG
	    std::cout << "Edge going over singularity detected; split" << std::endl;
#endif
      Standard_Boolean isFwd = ( E.Orientation() == TopAbs_FORWARD );
      E.Orientation ( TopAbs_FORWARD );

      //if( BRep_Tool::SameParameter(sbwd->Edge(i)) )
      //  sbe.RemovePCurve ( E, face );

      //10.04.2003 skl for using trimmed lines as pcurves
      ShapeAnalysis_Edge sae;
      if( BRep_Tool::SameParameter(sbwd->Edge(i)) )
        sbe.RemovePCurve ( E, face );
      else {
        if(sae.HasPCurve(E,face)) {
          Handle(Geom2d_Curve) C2d;
          Standard_Real fp2d,lp2d;
          if(sae.PCurve(E,face,C2d,fp2d,lp2d)) {
            if( !C2d->IsKind(STANDARD_TYPE(Geom2d_TrimmedCurve)) )
              sbe.RemovePCurve(E,face);
          }
        }
      }

//    myFixEdge->FixSameParameter ( E ); // to ensure SameRange & SP
      BRep_Builder B;
      TopoDS_Vertex V1, V2, V;
      //ShapeAnalysis_Edge sae;
      V1 = sae.FirstVertex ( E );
      V2 = sae.LastVertex ( E );
        
      Handle(ShapeExtend_WireData) sw = new ShapeExtend_WireData;
      for ( Standard_Integer k=0; k <= seq.Length(); k++ )
      {
        Standard_Real split = ( k < seq.Length() ? seq(k+1) : b );
        if ( k < seq.Length() )
        {
          B.MakeVertex ( V, C->Value(split), BRep_Tool::Tolerance(E) );
          //try increase tolerance before splitting
          Standard_Real aDist = BRep_Tool::Pnt(V1).Distance(BRep_Tool::Pnt(V));
          if (aDist < BRep_Tool::Tolerance(V1) * 1.01) {
            B.UpdateVertex(V1, Max(aDist, BRep_Tool::Tolerance(V1)));
            a = split;
            V1 = V;
            continue;
          }
          else
          {
            aDist = BRep_Tool::Pnt(V2).Distance(BRep_Tool::Pnt(V));
            if (aDist < BRep_Tool::Tolerance(V2) * 1.01) {
              B.UpdateVertex(V, Max(aDist, BRep_Tool::Tolerance(V2)));
              b = split;
              V2 = V;
              continue;
            }
          }
        }
        else
        {
          V = V2;
        }

        TopoDS_Edge edge = sbe.CopyReplaceVertices ( E, V1, V );
        if( BRep_Tool::SameParameter(sbwd->Edge(i)) ) {
          //TopoDS_Edge edge = sbe.CopyReplaceVertices ( E, V1, V );
          B.Range ( edge, a, split );
          sw->Add ( edge );
        }
        else {
          //TopoDS_Edge edge = sbe.CopyReplaceVertices(sbwd->Edge(i),V1,V);
          Handle(ShapeAnalysis_TransferParameters) sftp =
            new ShapeAnalysis_TransferParameters(E,face);
          sftp->TransferRange(edge, a, split, Standard_False);
          sw->Add(edge);
        }
        //sw->Add(edge);
        a = split;
        V1 = V;
      }
      if ( ! isFwd ) {
        sw->Reverse();
        E.Orientation ( TopAbs_REVERSED );
      }
      Context()->Replace ( E, sw->Wire() );
      UpdateWire();
      nb = sbwd->NbEdges();
      i--;
      continue;
    }
	}
	
	overdegen = i;
      }
    }

    //:c0 abv 20 Feb 98: treat case of curve going over degenerated pole and seam
    if ( overdegen && myAnalyzer->Surface()->IsUClosed(Precision()) ) {
      ShapeBuild_Edge sbe;
      Standard_Real URange, SUF, SUL, SVF, SVL;
      myAnalyzer->Surface()->Bounds(SUF, SUL, SVF, SVL);
      URange = (Abs(SUL - SUF));
      gp_XY vec(0,0);
      ShapeAnalysis_Edge sae;
      Standard_Integer k;
      for ( k = 1; k <= nb; k++) {
	Standard_Real cf, cl;
	Handle(Geom2d_Curve) c2d;
	if ( ! sae.PCurve ( sbwd->Edge(k), face, c2d, cf, cl, Standard_True ) ) break;
	vec += c2d->Value(cl).XY() - c2d->Value(cf).XY();
      }
      if ( k > nb && Abs ( Abs ( vec.X() ) - URange ) < 0.1 * URange ) {
	sbe.RemovePCurve (sbwd->Edge ( overdegen ), face);
	myFixEdge->Projector()->AdjustOverDegenMode() = Standard_False;
	myFixEdge->FixAddPCurve ( sbwd->Edge(overdegen), face, sbwd->IsSeam(overdegen), myAnalyzer->Surface(), Precision());
      }
#ifdef OCCT_DEBUG
      std::cout << "Edge going over singularity detected; pcurve adjusted" << std::endl;
#endif
    }
  }

  // add / remove pcurve
  if ( isReady && NeedFix ( myFixRemoveCurve3dMode, Standard_False ) ) {
    for ( i=1; i <= nb; i++ ) {
      myFixEdge->FixRemoveCurve3d ( sbwd->Edge(i) );
      if ( myFixEdge->Status ( ShapeExtend_DONE ) ) 
	myStatusEdgeCurves |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE4 );
      if ( myFixEdge->Status ( ShapeExtend_FAIL ) ) 
	myStatusEdgeCurves |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL4 );
    }
  }
  if ( NeedFix ( myFixAddCurve3dMode ) ) {
    for ( i=1; i <= nb; i++ ) {
      myFixEdge->FixAddCurve3d ( sbwd->Edge(i) );
      if ( myFixEdge->Status ( ShapeExtend_DONE ) ) 
	myStatusEdgeCurves |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE5 );
      if ( myFixEdge->Status ( ShapeExtend_FAIL ) ) {
        //:abv 29.08.01: Spatial_firex_lofting.sat: if 3d curve cannot
        // be built because edge has no pcurves either, remove that edge
        Handle(Geom2d_Curve) C;
        Handle(Geom_Surface) S;
        TopLoc_Location L;
        Standard_Real first = 0., last = 0.;
        BRep_Tool::CurveOnSurface ( sbwd->Edge(i), C, S, L, first, last );
        if ( C.IsNull() || Abs (last - first) < Precision::PConfusion())
        {
          SendWarning ( sbwd->Edge ( i ), Message_Msg ( "FixWire.FixCurve3d.Removed" ) );// Incomplete edge (with no pcurves or 3d curve) removed
          sbwd->Remove ( i-- );
          nb--;
          myStatusEdgeCurves |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE5 );
          if (i == nb)
          {
            FixClosed (Precision());
          }
          else
          {
            FixConnected (i + 1, Precision());
          }
        }
	myStatusEdgeCurves |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL5 );
      }
    }
  }
  
  // fix seam
  if ( isReady && NeedFix ( myFixSeamMode, Standard_False ) ) {
    for ( i=1; i <= nb; i++ ) {
      FixSeam ( i );
      if ( LastFixStatus ( ShapeExtend_DONE ) ) 
	myStatusEdgeCurves |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE6 );
      if ( LastFixStatus ( ShapeExtend_FAIL ) ) 
	myStatusEdgeCurves |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL6 );
    }
  }

  // fix shifted
  if ( isReady && NeedFix ( myFixShiftedMode ) ) {
    FixShifted();
    if ( LastFixStatus ( ShapeExtend_DONE ) ) 
      myStatusEdgeCurves |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE7 );
    if ( LastFixStatus ( ShapeExtend_FAIL ) ) 
      myStatusEdgeCurves |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL7 );
  }

  // fix same parameter
  if ( isReady && NeedFix ( myFixSameParameterMode ) ){
    for ( i=1; i <= nb; i++ ) {
      // skl 28.10.2004 for OCC6366 - check SameRange
      ShapeAnalysis_Edge sae;
      Standard_Real First, Last;
      Handle(Geom_Curve) tmpc3d = BRep_Tool::Curve(sbwd->Edge(i), First, Last);
      if(sae.HasPCurve(sbwd->Edge(i),face)) {
        Handle(Geom2d_Curve) C2d;
        Standard_Real fp2d,lp2d;
        if(sae.PCurve(sbwd->Edge(i),face,C2d,fp2d,lp2d, Standard_False)) {
          if( fabs(First-fp2d)>Precision::PConfusion() ||
              fabs(Last-lp2d)>Precision::PConfusion()    ) 
          {
            BRep_Builder B;
            B.SameRange(sbwd->Edge(i),Standard_False);
          }
          else if(!sae.CheckPCurveRange(First, Last, C2d))
          {
            //Replace pcurve
            TopLoc_Location L;
            const Handle(Geom_Surface)& S = BRep_Tool::Surface(face, L);
            ShapeBuild_Edge().RemovePCurve (sbwd->Edge(i),  S, L);
            myFixEdge->FixAddPCurve ( sbwd->Edge(i), face, sbwd->IsSeam(i), 
			 myAnalyzer->Surface(), Precision() );
            if ( myFixEdge->Status ( ShapeExtend_DONE ) ) 
              myStatusEdgeCurves |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE3 );
            if ( myFixEdge->Status ( ShapeExtend_FAIL ) ) 
              myStatusEdgeCurves |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL3 );
          }
        }
      }
      myFixEdge->FixSameParameter ( sbwd->Edge(i), Face());
      if ( myFixEdge->Status ( ShapeExtend_DONE ) ) 
	myStatusEdgeCurves |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE8 );
      if ( myFixEdge->Status ( ShapeExtend_FAIL ) ) 
	myStatusEdgeCurves |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL8 );
    }
  }

  //:abv 10.06.02: porting C40 -> dev (CC670-12608.stp): moved from Perform()
  // Update with face is needed for plane surfaces (w/o stored pcurves)
  if ( NeedFix ( myFixVertexToleranceMode ) )
  {
    for ( i=1; i <= nb; i++)
    {
      myFixEdge->FixVertexTolerance (sbwd->Edge (i), Face());
      if ( myFixEdge->Status ( ShapeExtend_DONE ) ) 
        myStatusEdgeCurves |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE8 );
      if ( myFixEdge->Status ( ShapeExtend_FAIL ) ) 
        myStatusEdgeCurves |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL8 );
    }
    if (!Context().IsNull() )
      UpdateWire();
  }
  

  return StatusEdgeCurves ( ShapeExtend_DONE );
}

//=======================================================================
//function : FixDegenerated
//purpose  : 
//=======================================================================

Standard_Boolean ShapeFix_Wire::FixDegenerated() 
{
  myStatusDegenerated = ShapeExtend::EncodeStatus ( ShapeExtend_OK );
  if ( ! IsReady() ) return Standard_False;
  
//  if ( ! myAnalyzer->Surface()->HasSingularities ( Precision() ) ) return;

  Standard_Integer lastcoded = -1, prevcoded = 0;
  Standard_Integer stop = ( myClosedMode ? 0 : 1 );
  for ( Standard_Integer i = NbEdges(); i > stop; i-- ) {
    FixDegenerated ( i );
    myStatusDegenerated |= myLastFixStatus;
    //:r0 abv 19 Mar 99: PRO7226.stp #489490: remove duplicated degenerated edges
    Standard_Integer coded = ( LastFixStatus ( ShapeExtend_DONE2 ) ? 1 : 0 );
    if ( lastcoded ==-1 ) lastcoded = coded;
    if ( coded && ( prevcoded || ( i ==1 && lastcoded ) ) && NbEdges() >1 ) {
      Handle(ShapeExtend_WireData) sbwd = WireData();
      BRep_Builder B;
      sbwd->Remove ( i );
      if ( ! prevcoded ) i = NbEdges();
      B.Degenerated ( sbwd->Edge ( i++ ), Standard_False );
      prevcoded = 0;
    }
    else prevcoded = coded; 
  }

  return StatusDegenerated ( ShapeExtend_DONE );
}


//=======================================================================
//function : FixSelfIntersection
//purpose  : Applies FixSelfIntersectingEdge and FixIntersectingEdges
//           and removes wrong edges
//=======================================================================

Standard_Boolean ShapeFix_Wire::FixSelfIntersection() 
{
  myStatusSelfIntersection = ShapeExtend::EncodeStatus ( ShapeExtend_OK );
  if ( ! IsReady() ) return Standard_False;

  Handle(ShapeExtend_WireData) sbwd = WireData();
  Standard_Integer nb = sbwd->NbEdges();
  
  if ( NeedFix ( myFixSelfIntersectingEdgeMode ) ) {
    if (myRemoveLoopMode<1)
      for ( Standard_Integer num=1; num <=nb; num++ ) 
      {
        FixSelfIntersectingEdge ( num );
        myStatusSelfIntersection |= myLastFixStatus;
      }
    else if (myRemoveLoopMode==1)
    {
      for ( Standard_Integer num=1; num <=nb; num++ )
      {
        FixSelfIntersectingEdge ( num );
        myStatusSelfIntersection |= myLastFixStatus;
        if(nb<sbwd->NbEdges()) num--;
        nb = sbwd->NbEdges();
      }
      FixClosed(Precision());
    }
  }
  
  if ( NeedFix ( myFixIntersectingEdgesMode ) )
  {
    Standard_Integer num = ( myClosedMode ? 1 : 2 );
    for ( ; nb >1 && num <= nb; num++ )
    {
      FixIntersectingEdges ( num );
      if ( LastFixStatus ( ShapeExtend_FAIL1 ) ) 
        myStatusSelfIntersection |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL1 );
      if ( LastFixStatus ( ShapeExtend_FAIL2 ) ) 
        myStatusSelfIntersection |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL2 );
      if ( ! LastFixStatus ( ShapeExtend_DONE ) ) continue;

      if ( LastFixStatus ( ShapeExtend_DONE1 ) ) 
        myStatusSelfIntersection |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE1 );
      if ( LastFixStatus ( ShapeExtend_DONE2 ) ) 
        myStatusSelfIntersection |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE2 );
      if(LastFixStatus (ShapeExtend_DONE6))
        myStatusSelfIntersection |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE6 );

      if ( /*! myTopoMode ||*/ nb < 3 )
      {
        //#86 rln 22.03.99 sim2.igs, entity 4292: After fixing of self-intersecting
        //BRepCheck finds one more self-intersection not found by ShapeAnalysis
        //%15 pdn 06.04.99 repeat until fixed CTS18546-2 entity 777
        
        // if the tolerance was modified we should recheck the result, if it was enough
        if ( LastFixStatus ( ShapeExtend_DONE7 ) ) //num--;
          FixIntersectingEdges ( num );
        continue;
      }

      if ( LastFixStatus ( ShapeExtend_DONE4 ) ) sbwd->Remove ( num );
      if ( LastFixStatus ( ShapeExtend_DONE3 ) ) sbwd->Remove ( num >1 ? num-1 : nb+num-1 );
      if ( LastFixStatus ( ShapeExtend_DONE4 ) ||
           LastFixStatus ( ShapeExtend_DONE3 ) )
      {
        myStatusSelfIntersection |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE3 );
        num = ( myClosedMode ? 1 : 2 );
        nb = sbwd->NbEdges();
#ifdef OCCT_DEBUG
        std::cout << "Warning: ShapeFix_Wire::FixSelfIntersection: Edge removed" << std::endl;
#endif
      }
      else
      {
        //#86 rln 22.03.99
        //%15 pdn 06.04.99 repeat until fixed CTS18546-2 entity 777
        FixIntersectingEdges ( num );
        /*if ( LastFixStatus ( ShapeExtend_DONE7 ) )*/
        // Always revisit the fixed edge
        //num--;
      }
    }
    if ( !Context().IsNull())
      UpdateWire();
  }


  //pdn 17.03.99 S4135 to avoid regression fixing not adjacent intersection
  if ( NeedFix ( myFixNonAdjacentIntersectingEdgesMode ) ) {

    ShapeFix_IntersectionTool ITool(Context(),Precision());
    Standard_Integer NbSplit=0, NbCut=0,NbRemoved=0;
    if(ITool.FixSelfIntersectWire(sbwd,myAnalyzer->Face(),NbSplit,NbCut,NbRemoved)) {
      myStatusSelfIntersection |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE5 );//gka 06.09.04
    }
    if( NbSplit>0 || NbRemoved>0 ) {
      if(NbRemoved>0) myStatusRemovedSegment = Standard_True;
      //Load(sbwd); commented by skl 29.12.2004 for OCC7624, instead this
      //            string inserted following three strings:
      myAnalyzer->Load ( sbwd );
      if ( ! Context().IsNull() ) UpdateWire();
      myShape.Nullify();
    }
#ifdef OCCT_DEBUG
    if (StatusSelfIntersection (ShapeExtend_DONE5))
      std::cout<<"Warning: ShapeFix_Wire::FixIntersection: Non-adjacent intersection fixed (split-"
        <<NbSplit<<", cut-"<<NbCut<<", removed-"<<NbRemoved<<")"<<std::endl;
#endif	  

/*
    Bnd_Array1OfBox2d boxes(1,nb);
    TopLoc_Location L;
    const Handle(Geom_Surface)& S = BRep_Tool::Surface(Face(), L);
    Handle(Geom2d_Curve) c2d;
    Standard_Real cf,cl;
    ShapeAnalysis_Edge sae;
    for(Standard_Integer i = 1; i <= nb; i++){
      TopoDS_Edge E = sbwd->Edge (i);
      if(sae.PCurve (E,S,L,c2d,cf,cl,Standard_False)) {
	Bnd_Box2d box;
        Geom2dAdaptor_Curve gac;
        Standard_Real aFirst = c2d->FirstParameter();
        Standard_Real aLast = c2d->LastParameter();
        if(c2d->IsKind(STANDARD_TYPE(Geom2d_BSplineCurve)) 
           && (cf < aFirst || cl > aLast)) {
          //pdn avoiding problems with segment in Bnd_Box
          gac.Load(c2d);
        }
        else
          gac.Load(c2d,cf,cl);
	BndLib_Add2dCurve::Add(gac,::Precision::Confusion(),box);
	boxes(i) = box;
      }
    }

    Standard_Boolean isFail = Standard_False, isDone = Standard_False;
    for(Standard_Integer num1 = 1; num1 < nb-1; num1++) {
      Standard_Integer fin = (num1 == 1 ? nb-1 : nb);
      for(Standard_Integer num2 = num1+2; num2 <= fin; num2++) 
	if(!boxes(num1).IsOut(boxes(num2))){
	  FixIntersectingEdges (num1, num2);
	  isFail |= LastFixStatus ( ShapeExtend_FAIL1 );
	  isDone |= LastFixStatus ( ShapeExtend_DONE1 );
	}
    }

    if(isFail)
      myStatusSelfIntersection |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL3 );
    if(isDone)
      myStatusSelfIntersection |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE5 );
#ifdef OCCT_DEBUG
    if (StatusSelfIntersection (ShapeExtend_DONE5))
      std::cout << "Warning: ShapeFix_Wire::FixSelfIntersection: Non adjacent intersection fixed" << std::endl;
#endif
*/
  }

  return StatusSelfIntersection ( ShapeExtend_DONE );
}


//=======================================================================
//function : FixLacking
//purpose  : 
//=======================================================================

Standard_Boolean ShapeFix_Wire::FixLacking ( const Standard_Boolean force ) 
{
  myStatusLacking = ShapeExtend::EncodeStatus ( ShapeExtend_OK );
  if ( ! IsReady() ) return Standard_False;
  
  Standard_Integer start = ( myClosedMode ? 1 : 2 );
  for ( Standard_Integer i = start; i <= NbEdges(); i++ ) {
    FixLacking ( i, force );
    myStatusLacking |= myLastFixStatus;
  }
  
  return StatusLacking ( ShapeExtend_DONE );
}


//=======================================================================
//function : FixClosed
//purpose  : 
//=======================================================================

Standard_Boolean ShapeFix_Wire::FixClosed (const Standard_Real prec) 
{
  myStatusClosed = ShapeExtend::EncodeStatus ( ShapeExtend_OK );
  if ( ! IsLoaded() || NbEdges() <1 ) return Standard_False;
  
  FixConnected ( 1, prec );
  if ( LastFixStatus ( ShapeExtend_DONE ) ) 
    myStatusClosed |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE1 );
  if ( LastFixStatus ( ShapeExtend_FAIL ) ) 
    myStatusClosed |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL1 );

  FixDegenerated ( 1 );
  if ( LastFixStatus ( ShapeExtend_DONE ) ) 
    myStatusClosed |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE2 );
  if ( LastFixStatus ( ShapeExtend_FAIL ) ) 
    myStatusClosed |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL2 );

  FixLacking ( 1 );
  if ( LastFixStatus ( ShapeExtend_DONE ) ) 
    myStatusClosed |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE3 );
  if ( LastFixStatus ( ShapeExtend_FAIL ) ) 
    myStatusClosed |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL3 );
  
  return StatusClosed ( ShapeExtend_DONE );
}


//#######################################################################
//  Fixing methods of advanced level
//#######################################################################
  
//=======================================================================
//function : FixReorder
//purpose  : 
//=======================================================================

Standard_Boolean ShapeFix_Wire::FixReorder (const ShapeAnalysis_WireOrder& wi) 
{
  myLastFixStatus = ShapeExtend::EncodeStatus ( ShapeExtend_OK );
  if ( ! IsLoaded() ) return Standard_False;
  
  Standard_Integer status = wi.Status();
  if ( status ==0 ) return Standard_False;
  if ( status <=-10 ) {
    myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL1 );
    return Standard_False;
  }

  Handle(ShapeExtend_WireData) sbwd = WireData();
  Standard_Integer i, nb = sbwd->NbEdges();
  if ( nb != wi.NbEdges() ) {  
    myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL2 );
    return Standard_False;  
  }
  // D abord on protege
  for (i = 1; i <= nb; i ++) {
    if ( wi.Ordered(i) == 0 ) {  
      myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL3 );
      return Standard_False;  
    }
  }

  Handle(TopTools_HSequenceOfShape) newedges = new TopTools_HSequenceOfShape();
  for ( i=1; i <= nb; i++ )
    newedges->Append ( sbwd->Edge ( wi.Ordered(i) ) );
  for ( i=1; i <= nb; i++ ) 
    sbwd->Set ( TopoDS::Edge ( newedges->Value(i) ), i );
  
  myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE1 );
  return Standard_True;
}


//=======================================================================
//function : FixSmall
//purpose  : 
//=======================================================================

Standard_Boolean ShapeFix_Wire::FixSmall (const Standard_Integer num,
					  const Standard_Boolean lockvtx,
					  const Standard_Real precsmall) 
{
  myLastFixStatus = ShapeExtend::EncodeStatus ( ShapeExtend_OK );
  if ( ! IsLoaded() || NbEdges() <=1 ) return Standard_False;

  // analysis:
  Handle(ShapeAnalysis_Wire) theAdvAnalyzer = myAnalyzer;
  if (theAdvAnalyzer.IsNull()) return Standard_False;
  Standard_Integer n = ( num >0 ? num : NbEdges() );
  theAdvAnalyzer->CheckSmall ( n, precsmall );
  if ( theAdvAnalyzer->LastCheckStatus ( ShapeExtend_FAIL ) ) {
    myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL1 );
//:n2    return Standard_False;
  }

  if ( ! theAdvAnalyzer->LastCheckStatus ( ShapeExtend_DONE ) ) return Standard_False;

  // OUI cette edge est NULLE

  if ( theAdvAnalyzer->LastCheckStatus ( ShapeExtend_DONE2 ) ) {
    // edge is small, but vertices are not the same..
    if ( lockvtx || ! myTopoMode ) {
      myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL2 );
      return Standard_False;
    }
    myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE2 );
  }
  else myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE1 );

  // action: remove edge
  if ( ! Context().IsNull() ) 
    Context()->Remove(WireData()->Edge(n));
  SendWarning ( WireData()->Edge ( n ), Message_Msg ( "FixAdvWire.FixSmall.MSG0" ) ); //Small edge(s) removed
  WireData()->Remove ( n );
  
  // call FixConnected in the case if vertices of the small edge were not the same
  if ( LastFixStatus ( ShapeExtend_DONE2 ) ) {
    Standard_Integer savLastFixStatus = myLastFixStatus;
    //#43 rln 20.11.98 S4054 CTS18544 entity 21734 removing last edge
    FixConnected ( n <= NbEdges() ? n : 1, precsmall );
    if ( LastFixStatus ( ShapeExtend_FAIL ) )
      savLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL3 );
    myLastFixStatus = savLastFixStatus;
  }

  return Standard_True;
}


//=======================================================================
//function : FixConnected
//purpose  : 
//=======================================================================

Standard_Boolean ShapeFix_Wire::FixConnected (const Standard_Integer num,
					      const Standard_Real prec) 
{
  myLastFixStatus = ShapeExtend::EncodeStatus ( ShapeExtend_OK );
  if ( ! IsLoaded() || NbEdges() <=0 ) return Standard_False;

  // analysis
  
  myAnalyzer->CheckConnected ( num, prec < 0 ? MaxTolerance() : prec );
  if ( myAnalyzer->LastCheckStatus ( ShapeExtend_FAIL ) ) {
    myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL1 );
  }
  if ( ! myAnalyzer->LastCheckStatus ( ShapeExtend_DONE ) ) return Standard_False;

  // action: replacing vertex
  
  Handle(ShapeExtend_WireData) sbwd = WireData();
  Standard_Integer n2 = ( num >0 ? num  : sbwd->NbEdges() );
  Standard_Integer n1 = ( n2  >1 ? n2-1 : sbwd->NbEdges() );
  TopoDS_Edge E1 = sbwd->Edge(n1);
  TopoDS_Edge E2 = sbwd->Edge(n2);
  
  ShapeAnalysis_Edge sae;
  TopoDS_Vertex V1 = sae.LastVertex (E1);
  TopoDS_Vertex V2 = sae.FirstVertex (E2);
  TopoDS_Vertex V;
  
  if ( myAnalyzer->LastCheckStatus ( ShapeExtend_DONE1 ) ) { // absolutely confused
    myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE1 );
    //#40 rln 18.11.98 S4054 BUC60035 entity 2393 (2-nd sub-curve is edge with the same vertex)
    if ( V2.IsSame ( sae.LastVertex (E2) ) ) {
      V = V2;
      if ( ! Context().IsNull() ) 
	Context()->Replace ( V1, V.Oriented(V1.Orientation()) );
    }
    else {
      V = V1;
      if ( ! Context().IsNull() ) 
	Context()->Replace ( V2, V.Oriented(V2.Orientation()) );
    }
  } 
  else {    // on moyenne ...
    if ( myAnalyzer->LastCheckStatus ( ShapeExtend_DONE2 ) )
      myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE2 );
    else myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE3 );
    ShapeBuild_Vertex sbv; 
    V = sbv.CombineVertex ( V1, V2, 1.0001 );
    if ( ! Context().IsNull() ) {
      Context()->Replace ( V1, V.Oriented(V1.Orientation()) );
      Context()->Replace ( V2, V.Oriented(V2.Orientation()) );
    }
  }

  // replace vertices to a new one
  ShapeBuild_Edge sbe;
  if ( sbwd->NbEdges() <2 ) {
    if(E2.Free() && myTopoMode) {
      BRep_Builder B;
      B.Remove(E2,sae.FirstVertex(E2));
      B.Remove(E2,sae.LastVertex(E2));
      B.Add(E2,V.Oriented(TopAbs_FORWARD));
      B.Add(E2,V.Oriented(TopAbs_REVERSED));
    }
    else {
      TopoDS_Edge tmpE = sbe.CopyReplaceVertices ( E2, V, V );
      sbwd->Set ( tmpE, n2 );
      if ( ! Context().IsNull() ) Context()->Replace(E2,tmpE);
    }
  }
  else {
    if(E2.Free() &&E1.Free() && myTopoMode) {
      BRep_Builder B;
      B.Remove(E2,sae.FirstVertex(E2));
      B.Add(E2,V.Oriented(TopAbs_FORWARD));
      if ( ! myAnalyzer->LastCheckStatus ( ShapeExtend_DONE1 ) ||
	  sae.FirstVertex (E2).IsSame (sae.LastVertex (E2)) ) {
	B.Remove(E1,sae.LastVertex(E1));
	B.Add(E1,V.Oriented(TopAbs_REVERSED));
      }
    }
    else {
      TopoDS_Edge tmpE2 = sbe.CopyReplaceVertices ( E2, V, TopoDS_Vertex() );
      sbwd->Set ( tmpE2, n2 );
      if ( ! Context().IsNull() ) Context()->Replace(E2,tmpE2);
      if ( ! myAnalyzer->LastCheckStatus ( ShapeExtend_DONE1 ) ||
	  sae.FirstVertex (E2).IsSame (sae.LastVertex (E2)) ) {
	TopoDS_Edge tmpE1 = sbe.CopyReplaceVertices ( E1, TopoDS_Vertex(), V );
	sbwd->Set (tmpE1, n1 );
	if ( ! Context().IsNull() ) Context()->Replace(E1,tmpE1);
      }
    }
  }
  if ( ! Context().IsNull() ) UpdateWire();
  
  return Standard_True;
}


//=======================================================================
//function : FixSeam
//purpose  : 
//=======================================================================

Standard_Boolean ShapeFix_Wire::FixSeam (const Standard_Integer num) 
{
  myLastFixStatus = ShapeExtend::EncodeStatus ( ShapeExtend_OK );
  if ( ! IsReady() ) return Standard_False;

  Handle(Geom2d_Curve) C1, C2;
  Standard_Real cf, cl;
  if ( ! myAnalyzer->CheckSeam (num, C1, C2, cf, cl) ) return Standard_False;

  BRep_Builder B;
  TopoDS_Edge E = WireData()->Edge ( num >0 ? num : NbEdges() );
  B.UpdateEdge (E, C2,C1, Face(), 0.); //:S4136: BRep_Tool::Tolerance(E)
  B.Range (E, Face(),cf,cl);
  myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE1 );
  
  return Standard_True;
}

//=======================================================================
//function : FixShifted
//purpose  : fix parametric curves which may be shifted
// to whole parametric range of closed surface as result of recomputing
// from 3d representation.
// This can be a curve on a seam or near it.
// This function is to be called before FixDegenerated.
// LIMITATION: this function cannot fix cases when, e.g., closed wire is 
// composed of two meridians of the sphere and one of them is seam.
// NOTE: wire is supposed to be closed and sorted !
//=======================================================================

//:p4 abv 23.02.99: PRO9234 #15720: update UV points of edge 
static void UpdateEdgeUVPoints (TopoDS_Edge &E, const TopoDS_Face &F)
{
  Standard_Real first, last;
  BRep_Tool::Range ( E, F, first, last );
  BRep_Builder().Range ( E, F, first, last );
}


//=======================================================================
//function : FixShifted
//purpose  : 
//=======================================================================

Standard_Boolean ShapeFix_Wire::FixShifted() 
{
  myLastFixStatus = ShapeExtend::EncodeStatus ( ShapeExtend_OK );
  if ( ! IsReady() ) return Standard_False;

  Handle(ShapeAnalysis_Surface) surf = myAnalyzer->Surface();
  //#78 rln 12.03.99 S4135: checking spatial closure with Precision
  Standard_Boolean uclosed = surf->IsUClosed(Precision());
  Standard_Boolean vclosed = surf->IsVClosed(Precision()) || surf->Surface()->IsKind (STANDARD_TYPE(Geom_SphericalSurface));
  //#67 rln 01.03.99 S4135: ims010.igs entity D11900 (2D contour is 2*PI higher than V range [-pi/2,p/2])
  
  // PTV 26.06.2002 begin
  // CTS18546-2.igs entity 2222: base curve is periodic and 2dcurve is shifted
  Standard_Boolean IsVCrvClosed = Standard_False;
  Standard_Real VRange = 1.;
  if (surf->Surface()->IsKind (STANDARD_TYPE(Geom_SurfaceOfRevolution))) {
    Handle(Geom_SurfaceOfRevolution) aSurOfRev = Handle(Geom_SurfaceOfRevolution)::DownCast(surf->Surface());
    Handle(Geom_Curve) aBaseCrv = aSurOfRev->BasisCurve();
    while ( (aBaseCrv->IsKind(STANDARD_TYPE(Geom_OffsetCurve))) ||
           (aBaseCrv->IsKind(STANDARD_TYPE(Geom_TrimmedCurve))) ) {
      if (aBaseCrv->IsKind(STANDARD_TYPE(Geom_OffsetCurve)))
        aBaseCrv = Handle(Geom_OffsetCurve)::DownCast(aBaseCrv)->BasisCurve();
      if (aBaseCrv->IsKind(STANDARD_TYPE(Geom_TrimmedCurve)))
        aBaseCrv = Handle(Geom_TrimmedCurve)::DownCast(aBaseCrv)->BasisCurve();
    }
    if (aBaseCrv->IsPeriodic()) {
      vclosed = Standard_True;
      VRange = aBaseCrv->Period();
      IsVCrvClosed = Standard_True;
#ifdef OCCT_DEBUG
      std::cout << "Warning: ShapeFix_Wire::FixShifted set vclosed True for Surface of Revolution" << std::endl;
#endif
    }
  }
  // PTV 26.06.2002 end
  if ( ! uclosed && ! vclosed ) return Standard_False; 
  
  Standard_Real URange, /*VRange,*/ SUF, SUL, SVF, SVL;
  surf->Surface()->Bounds ( SUF, SUL, SVF, SVL );
  Standard_Real SUMid, SVMid;
  SUMid = 0.5*(SUF+SUL);
  SVMid = 0.5*(SVF+SVL);
  if (uclosed) URange = Abs ( SUL - SUF );
  else         URange = RealLast();
  if (!IsVCrvClosed) {
    if (vclosed) VRange = Abs ( SVL - SVF );
    else         VRange = RealLast();
  }
  Standard_Real UTol = 0.2 * URange, VTol = 0.2 * VRange;

  Handle(ShapeExtend_WireData) sbwdOring = WireData();
  ShapeAnalysis_Edge sae;
  Handle(ShapeExtend_WireData) sbwd = new ShapeExtend_WireData;
  for ( Standard_Integer i=1; i <= sbwdOring->NbEdges(); i++ ) {
    TopoDS_Edge E1 = sbwdOring->Edge ( i );
    if ( BRep_Tool::Degenerated(E1) && !sae.HasPCurve(E1,Face()))
      continue;
    
    sbwd->Add(E1);
  }
  
  ShapeBuild_Edge sbe;
  Standard_Integer nb = sbwd->NbEdges();
  Standard_Boolean end = (nb == 0), degstop = Standard_False;
  Standard_Integer stop = nb;
  Standard_Integer degn2 = 0;
  gp_Pnt pdeg;
  //pdn 17.12.98 r0901_ec 38237 to shift wire at 0
 
  //GeomAdaptor_Surface& GAS = myAnalyzer->Surface()->Adaptor3d()->ChangeSurface(); //SK
  Bnd_Box2d box;
  for ( Standard_Integer n2=1, n1=nb; ! end; n1 = n2++ ) {
    if ( n2 > nb ) n2 = 1;
    if ( n2 == stop ) end = Standard_True;

    TopoDS_Edge E1 = sbwd->Edge ( n1 );
    TopoDS_Edge E2 = sbwd->Edge ( n2 );

    if ( BRep_Tool::Degenerated(E1) || BRep_Tool::Degenerated(E2) )
    {
      if ( ! degstop )
      {
        stop = n2;
        degstop = Standard_True;
      }
      continue;
    }

    TopoDS_Vertex V = sae.FirstVertex ( E2 );
    if (V.IsNull())
      continue;

    gp_Pnt p = BRep_Tool::Pnt ( V );
  
    Standard_Real a1 = 0., b1 = 0., a2 = 0., b2 = 0.;
    Handle(Geom2d_Curve) c2d1, c2d2;

    //:abv 29.08.01: torCuts.sat: distinguish degeneration by U and by V;
    // only corresponding move is prohibited
//    Standard_Boolean isDeg = surf->IsDegenerated ( p, Max ( Precision(), BRep_Tool::Tolerance(V) ) );
    Standard_Integer isDeg = 0;
    gp_Pnt2d degP1, degP2;
    Standard_Real degT1, degT2;
    if ( surf->DegeneratedValues ( p, Max ( Precision(), BRep_Tool::Tolerance(V) ),
                                   degP1, degP2, degT1, degT2 ) )
      isDeg = ( Abs ( degP1.X() - degP2.X() ) > Abs ( degP1.Y() - degP2.Y() ) ? 1 : 2 );

    // abv 23 Feb 00: UKI60107-6 210: additional check for near-degenerated case
    //smh#15 PRO19800. Check if the surface is surface of revolution.
    if (surf->Surface()->IsKind (STANDARD_TYPE(Geom_SurfaceOfRevolution))) {
      if ( ! isDeg && ! vclosed ) {
	if ( c2d1.IsNull() && ! sae.PCurve ( E1, Face(), c2d1, a1, b1, Standard_True ) ) continue;
	gp_Pnt2d p1 ( SUF, c2d1->Value(b1).Y() );
	gp_Pnt2d p2 ( SUL, c2d1->Value(b1).Y() );
	if ( surf->IsDegenerated ( p1, p2, MaxTolerance(), 10 ) &&
	     ! surf->IsDegenerated ( c2d1->Value(a1), c2d1->Value(b1), MaxTolerance(), 10 ) ) // abv 31.07.00: trj4_pm1-ec-214.stp #31274: still allow work if edge already exists 
	  isDeg = 1;
      }
      if ( ! isDeg && ! uclosed ) {
	if ( c2d1.IsNull() && ! sae.PCurve ( E1, Face(), c2d1, a1, b1, Standard_True ) ) continue;
	gp_Pnt2d p1 ( c2d1->Value(b1).X(), SVF );
	gp_Pnt2d p2 ( c2d1->Value(b1).X(), SVL );
	if ( surf->IsDegenerated ( p1, p2, MaxTolerance(), 10 ) &&
	     ! surf->IsDegenerated ( c2d1->Value(a1), c2d1->Value(b1), MaxTolerance(), 10 ) ) // abv 31.07.00: trj4_pm1-ec-214.stp #31274: still allow work if edge already exists 
	  isDeg = 2;
      }
    }

    if ( isDeg )
    {
      if ( ! degstop )
      {
        stop = n2;
        degstop = Standard_True;
      }

      if ( ! degn2 )
      {
        degn2 = n2;
        pdeg = p;
      }
      else
      {
        if ( pdeg.SquareDistance(p) < Precision() * Precision() )
        {
          degn2 = n2;
          //if ( stop < n2 ) { stop = n2; degstop = Standard_True; }
        }
        else
        {
          Standard_Real ax1 = 0., bx1 = 0., ax2 = 0., bx2 = 0.;
          Handle(Geom2d_Curve) cx1, cx2;
          if (  ( c2d1.IsNull() && ! sae.PCurve ( E1, Face(), c2d1, a1, b1, Standard_True ) ) ||
                ( c2d2.IsNull() && ! sae.PCurve ( E2, Face(), c2d2, a2, b2, Standard_True ) ) ||
                ! sae.PCurve ( sbwd->Edge ( degn2 >1 ? degn2-1 : nb ), Face(), cx1, ax1, bx1, Standard_True ) ||
                ! sae.PCurve ( sbwd->Edge ( degn2 ), Face(), cx2, ax2, bx2, Standard_True ) )
          {
            myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL1 );
            continue;
          }
          gp_Pnt2d pd1 = cx1->Value ( bx1 );
          gp_Pnt2d pd2 = cx2->Value ( ax2 );
          gp_Pnt2d pn1 = c2d1->Value ( b1 );
          gp_Pnt2d pn2 = c2d2->Value ( a2 );
          gp_Vec2d x(0.,0.); // shift vector
          Standard_Real period;
          if ( uclosed ) { x.SetX ( 1. ); period = URange; }
          else { x.SetY ( 1. ); period = VRange; }
          Standard_Real rot1 = ( pn1.XY() - pd2.XY() ) ^ x.XY();
          Standard_Real rot2 = ( pd1.XY() - pn2.XY() ) ^ x.XY();
          Standard_Real scld = ( pd2.XY() - pd1.XY() ) * x.XY();
          Standard_Real scln = ( pn2.XY() - pn1.XY() ) * x.XY();
          if (  rot1 * rot2 < -::Precision::PConfusion() && 
                scld * scln < -::Precision::PConfusion() && 
                Abs ( scln ) > 0.1 * period && Abs ( scld ) > 0.1 * period && 
                rot1 * scld > ::Precision::PConfusion() && 
                rot2 * scln > ::Precision::PConfusion() )
          {
            // abv 02 Mar 00: trying more sophisticated analysis (ie_exhaust-A.stp #37520)
            Standard_Real sign = ( rot2 >0 ? 1. : -1. );
            Standard_Real deep1 = Min ( sign * ( pn2.XY() * x.XY() ),
                                  Min ( sign * ( pd1.XY() * x.XY() ),
                                  Min ( sign * ( c2d2->Value(b2 ).XY() * x.XY() ),
                                  Min ( sign * (  cx1->Value(ax1).XY() * x.XY() ),
                                  Min ( sign * ( c2d2->Value(0.5*(a2 +b2 )).XY() * x.XY() ),
                                        sign * (  cx1->Value(0.5*(ax1+bx1)).XY() * x.XY() ) ) ) ) ) );
            Standard_Real deep2 = Max ( sign * ( pn1.XY() * x.XY() ),
                                  Max ( sign * ( pd2.XY() * x.XY() ),
                                  Max ( sign * ( c2d1->Value(a1 ).XY() * x.XY() ),
                                  Max ( sign * (  cx2->Value(bx2).XY() * x.XY() ),
                                  Max ( sign * ( c2d1->Value(0.5*(a1 +b1 )).XY() * x.XY() ),
                                        sign * (  cx2->Value(0.5*(ax2+bx2)).XY() * x.XY() ) ) ) ) ) );
            Standard_Real deep = deep2 - deep1; // estimated current size of wire by x
            // pdn 30 Oct 00: trying correct period [0,period] (trj5_k1-tc-203.stp #4698)
            Standard_Real dx = ShapeAnalysis::AdjustToPeriod ( deep, ::Precision::PConfusion(), period+::Precision::PConfusion()); 
            x *= ( scld >0 ? -dx : dx );
            //x *= ( Abs(scld-scln) > 1.5 * period ? 2. : 1. ) *
            //     ( scld >0 ? -period : period );
            gp_Trsf2d Shift;
            Shift.SetTranslation ( x );
            for ( Standard_Integer k=degn2; ; k++ )
            {
              if ( k > nb ) k = 1;
              if ( k == n2 ) break;
              TopoDS_Edge edge = sbwd->Edge ( k );
              if ( ! sae.PCurve ( edge, Face(), cx1, ax1, bx1, Standard_True ) ) continue;
              //cx1->Transform ( Shift );
              // skl 15.05.2002 for OCC208 (if few edges have reference to one pcurve)
              Handle(Geom2d_Curve) cx1new = Handle(Geom2d_Curve)::DownCast(cx1->Transformed(Shift));
              sbe.ReplacePCurve(edge,cx1new,Face());
              UpdateEdgeUVPoints ( edge, Face() );
            }
            myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE1 );
#ifdef OCCT_DEBUG
            std::cout << "Info: ShapeFix_Wire::FixShifted(): bi - meridian case fixed" << std::endl;
#endif
            continue;
          }
          //degn2 = n2; pdeg = p; // ie_exhaust-A.stp #37520
        }
      }
/*
      // pdn to fix half sphere
      TopoDS_Vertex VE = sae.LastVertex ( E2 );
      gp_Pnt pe = BRep_Tool::Pnt ( VE );
      //pdn is second vertex on singular point ?
      if ( surf->IsDegenerated ( pe, Max ( Precision(), BRep_Tool::Tolerance(V) ) ) ) {
	if ( ( c2d1.IsNull() && ! sae.PCurve ( E1, Face(), c2d1, a1, b1, Standard_True ) ) ||
	     ( c2d2.IsNull() && ! sae.PCurve ( E2, Face(), c2d2, a2, b2, Standard_True ) ) ) {
	  myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL1 );
	  continue;
	}
	gp_Pnt2d p2d1 = c2d1->Value ( b1 ), p2f = c2d2->Value ( a2 ), p2l = c2d2->Value ( b2 );
	Standard_Real pres2 = ::Precision::PConfusion();
	Standard_Real du = 0.,dv = 0.;
	//#79 rln 15.03.99 S4135: bmarkmdl.igs entity 633 (incorrectly oriented contour) check for gap
	if(uclosed&&(Abs(p2f.X()-p2l.X())<pres2)&&Abs(p2d1.X()-p2f.X())>GAS.UResolution(Precision())) {
	  if((Abs(p2f.X()-SUF)<pres2)&&(p2f.Y()<p2l.Y()))
	    du = URange;
	  if((Abs(p2f.X()-SUL)<pres2)&&(p2f.Y()>p2l.Y()))
	    du = -URange;
	} 
 	if(vclosed&&(Abs(p2f.Y()-p2l.Y())<pres2)&&Abs(p2d1.Y()-p2f.Y())>GAS.VResolution(Precision())) {
	  if((Abs(p2f.Y()-SVF)<pres2)&&(p2f.X()>p2l.X()))
	    dv = VRange;
 	  if((Abs(p2f.Y()-SVL)<pres2)&&(p2f.X()<p2l.X()))
	    dv = -VRange;
	} 
	if ( du ==0. && dv == 0. ) continue;
	myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE1 );
	gp_Trsf2d Shift;
	Shift.SetTranslation ( gp_Vec2d ( du, dv ) );
	c2d2->Transform ( Shift );
	UpdateEdgeUVPoints ( E2, Face() );//rln 15.03.99 syntax correction :E1
      }
*/
//:abv 29.08.01: torCuts.sat:      continue;
    }

    if ( ( c2d1.IsNull() && ! sae.PCurve ( E1, Face(), c2d1, a1, b1, Standard_True ) ) ||
         ( c2d2.IsNull() && ! sae.PCurve ( E2, Face(), c2d2, a2, b2, Standard_True ) ) ) {
      myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL1 );
      continue;
    }
    gp_Pnt2d p2d1 = c2d1->Value ( b1 );
    gp_Pnt2d p2d2 = c2d2->Value ( a2 );
    box.Add ( p2d1 );

    Standard_Real du=0., dv=0.;
    if ( uclosed && isDeg != 1 ) {
      Standard_Real dx = Abs ( p2d2.X() - p2d1.X() );
      if ( dx > URange - UTol ) 
        du = ShapeAnalysis::AdjustByPeriod ( p2d2.X(), p2d1.X(), URange );
      else if ( dx > UTol && stop == nb ) stop = n2; //:abv 29.08.01: torCuts2.stp
    }
    if ( vclosed && isDeg != 2 ) {
      Standard_Real dy = Abs ( p2d2.Y() - p2d1.Y() );
      if ( dy > VRange - VTol ) 
        dv = ShapeAnalysis::AdjustByPeriod ( p2d2.Y(), p2d1.Y(), VRange );
      else if ( dy > VTol && stop == nb ) stop = n2;
    }
    if ( du ==0. && dv == 0. ) continue;

    myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE1 );
    gp_Trsf2d Shift;
    Shift.SetTranslation ( gp_Vec2d ( du, dv ) );
    //c2d2->Transform ( Shift );
    // skl 15.05.2002 for OCC208 (if few edges have reference to one pcurve)
    Handle(Geom2d_Curve) c2d2new = Handle(Geom2d_Curve)::DownCast(c2d2->Transformed(Shift));
    sbe.ReplacePCurve(E2,c2d2new,Face());
    UpdateEdgeUVPoints ( E2, Face() );
  }
  if ( box.IsVoid() ) return Standard_False; //#3 smh 01.04.99. S4163: Overflow, when box is void.

  Standard_Real umin, vmin, umax, vmax;
  box.Get ( umin, vmin, umax, vmax );
  if ( Abs ( umin + umax - SUF - SUL ) < URange &&
       Abs ( vmin + vmax - SVF - SVL ) < VRange &&
       ! LastFixStatus ( ShapeExtend_DONE ) ) return Standard_False;

  box.SetVoid();
  Standard_Integer n; // svv Jan11 2000 : porting on DEC
  for ( n=1; n <= nb; n++ ) {
    Standard_Real a, b;
    Handle(Geom2d_Curve) c2d;
    if ( ! sae.PCurve ( sbwd->Edge(n), Face(), c2d, a, b, Standard_True ) ) continue;
    box.Add ( c2d->Value ( a ) );
    box.Add ( c2d->Value ( 0.5 * ( a + b ) ) );
  }
  box.Get ( umin, vmin, umax, vmax );

  Standard_Real du=0., dv=0.;

  if ( uclosed ) {
    Standard_Real umid = 0.5 * ( umin + umax );
//     du = ShapeAnalysis::AdjustToPeriod(umid, SUF, SUL);
    // PTV 26.06.2002 xloop torus-apple iges face mode
    du = ShapeAnalysis::AdjustByPeriod(umid, SUMid, URange);
  }
  if ( vclosed ) {
    Standard_Real vmid = 0.5 * ( vmin + vmax );
//     dv = ShapeAnalysis::AdjustToPeriod(vmid, SVF, SVL);
    // PTV 26.06.2002 xloop torus-apple iges face mode
    dv = ShapeAnalysis::AdjustByPeriod(vmid, SVMid, VRange);
  }

  if ( du ==0. && dv == 0. ) return Standard_True;

  myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE2 );
  
  gp_Trsf2d Shift;
  Shift.SetTranslation ( gp_Vec2d ( du, dv ) );

  for ( n=1; n <= sbwdOring->NbEdges(); n++ ) {
    Standard_Real a, b;
    Handle(Geom2d_Curve) c2d;
    TopoDS_Edge ed = sbwdOring->Edge(n);
    if ( ! sae.PCurve ( ed, Face(), c2d, a, b, Standard_True ) ) continue;
    // skl 15.05.2002 for OCC208 (if few edges have reference to one pcurve)
    Handle(Geom2d_Curve) c2d2 = Handle(Geom2d_Curve)::DownCast(c2d->Transformed(Shift));
    sbe.ReplacePCurve(ed,c2d2,Face());
    UpdateEdgeUVPoints ( ed, Face() );
  }
  return Standard_True;
}

//=======================================================================
//function : FixDegenerated
//purpose  : 
//=======================================================================

Standard_Boolean ShapeFix_Wire::FixDegenerated (const Standard_Integer num) 
{
  myLastFixStatus = ShapeExtend::EncodeStatus ( ShapeExtend_OK );
  if ( ! IsReady() ) return Standard_False;

  // analysis
  gp_Pnt2d p2d1, p2d2;
  myAnalyzer->CheckDegenerated ( num, p2d1, p2d2 );
  if ( myAnalyzer->LastCheckStatus ( ShapeExtend_FAIL1 ) ) {
    myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL1 );
  }
  //: abv 29.08.01: torHalf2.sat: if edge was encoded as degenerated but 
  //  has no pcurve and no singularity is found at that point, remove it
  if ( myAnalyzer->LastCheckStatus ( ShapeExtend_FAIL2 ) ) {
    WireData()->Remove ( num );
    myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE3 );
    return Standard_True;
  }
  if ( ! myAnalyzer->LastCheckStatus ( ShapeExtend_DONE ) ) return Standard_False;
  
  // action: create degenerated edge and insert it (or replace)

  gp_Vec2d vect2d ( p2d1, p2d2 );
  gp_Dir2d dir2d ( vect2d );
  Handle(Geom2d_Line) line2d = new Geom2d_Line ( p2d1, dir2d );

  TopoDS_Edge degEdge;
  BRep_Builder B;
  B.MakeEdge ( degEdge );
  B.Degenerated ( degEdge, Standard_True );
  B.UpdateEdge ( degEdge, line2d, Face(), ::Precision::Confusion() );
  B.Range ( degEdge, Face(), 0., vect2d.Magnitude() );

  Handle(ShapeExtend_WireData) sbwd = WireData();
  Standard_Integer n2 = ( num >0 ? num  : sbwd->NbEdges() );
  Standard_Integer n1 = ( n2  >1 ? n2-1 : sbwd->NbEdges() );
  
  Standard_Boolean lack = myAnalyzer->LastCheckStatus ( ShapeExtend_DONE1 );
  Standard_Integer n3 = ( lack ? n2 : ( n2 < sbwd->NbEdges() ? n2+1 : 1 ) );
  
  ShapeAnalysis_Edge sae;
  TopoDS_Vertex V1 = sae.LastVertex ( sbwd->Edge ( n1 ) );
  TopoDS_Vertex V2 = sae.FirstVertex ( sbwd->Edge ( n3 ) );
  
  V1.Orientation(TopAbs_FORWARD);
  V2.Orientation(TopAbs_REVERSED);
  B.Add(degEdge,V1);
  B.Add(degEdge,V2);
  degEdge.Orientation(TopAbs_FORWARD);

  if ( lack ) {
    sbwd->Add ( degEdge, n2 );
    myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE1 );
  }
  else {
    sbwd->Set ( degEdge, n2 );
    myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE2 );
  }

//  commented to avoid extra messages
//  SendWarning ( degEdge, Message_Msg ( "FixWire.FixDegenerated.MSG0" ) );// Degenerated edge(s) detected

  return Standard_True;
}

//=======================================================================
//function : FixSelfIntersectingEdge
//purpose  : Tests edge for self-intersection and updates tolerance of vertex
//           if intersection is found
//           Returns True if tolerance was increased
//=======================================================================

// Create edge on basis of E with new pcurve and call FixSP
// Return resulting tolerance and modified pcurve
static Standard_Boolean TryNewPCurve (const TopoDS_Edge &E, const TopoDS_Face &face,
				      Handle(Geom2d_Curve) &c2d,
				      Standard_Real &first,
				      Standard_Real &last,
				      Standard_Real &tol)
{
  Standard_Real f, l;
  Handle(Geom_Curve) crv = BRep_Tool::Curve ( E, f, l );
  if ( crv.IsNull() ) return Standard_False;

  // make temp edge and compute tolerance
  BRepBuilderAPI_MakeEdge mkedge ( crv, f, l );

  ShapeBuild_Edge SBE;        //skl 17.07.2001
  SBE.SetRange3d(mkedge,f,l); //skl 17.07.2001

  if ( ! mkedge.IsDone() ) return Standard_False;

  TopoDS_Edge edge = mkedge;
  BRep_Builder B;
  B.UpdateEdge ( edge, c2d, face, 0. );
  B.Range ( edge, face, first, last );
  B.SameRange ( edge, Standard_False );
// no call to BRepLib:  B.SameParameter ( edge, Standard_False );

  Handle(ShapeFix_Edge) sfe = new ShapeFix_Edge;
  sfe->FixSameParameter ( edge, face ); 
  c2d = BRep_Tool::CurveOnSurface ( edge, face, first, last );
  tol = BRep_Tool::Tolerance ( edge );
  return Standard_True;
}
  
//:k3 abv 24 Dec 98: BUC50070 #26682 and #30087: 
// Try to cut out the loop on the pcurve and make new pcurve by concatenating
// the parts.
// If result is not SameParameter with prec, does nothing and returns False
// Warning: resulting pcurve will be C0

//=======================================================================
//function : howMuchPCurves
//purpose  : OCC901
//=======================================================================
static Standard_Integer howMuchPCurves (const TopoDS_Edge &E)
{
  Standard_Integer count = 0;
  BRep_ListIteratorOfListOfCurveRepresentation itcr
    ((*((Handle(BRep_TEdge)*)&E.TShape()))->ChangeCurves());

  while (itcr.More()) {
    const Handle(BRep_CurveRepresentation)& cr = itcr.Value();
    if ( cr->IsCurveOnSurface() )
      count++;
    itcr.Next();
  }
    
  return count;
}


//=======================================================================
//function : RemoveLoop
//purpose  : 
//=======================================================================
static Standard_Boolean RemoveLoop (TopoDS_Edge &E, const TopoDS_Face &face,
				    const IntRes2d_IntersectionPoint &IP,
				    const Standard_Real tolfact,
				    const Standard_Real prec,
                                    const Standard_Boolean RemoveLoop3d)
{
  Standard_Boolean loopRemoved3d;
  if ( BRep_Tool::IsClosed ( E, face ) ) return Standard_False;
  
  Standard_Real f, l;
  Handle(Geom_Curve) crv = BRep_Tool::Curve ( E, f, l );

  Standard_Real t1 = IP.ParamOnFirst();
  Standard_Real t2 = IP.ParamOnSecond();
  if ( t1 > t2 ) { Standard_Real t = t1; t1 = t2; t2 = t; }

  ShapeAnalysis_Edge sae;
  Standard_Real a, b;
  Handle(Geom2d_Curve) c2d;
  if ( ! sae.PCurve ( E, face, c2d, a, b, Standard_False ) ) 
    return Standard_False;

#ifdef OCCT_DEBUG
  std::cout << "Cut Loop: params (" << t1 << ", " << t2;
#endif
  GeomAdaptor_Curve GAC ( crv, f, l );
  Standard_Real dt = tolfact * GAC.Resolution(prec);
  t1 -= dt; //1e-3;//::Precision::PConfusion();
  t2 += dt; //1e-3;//::Precision::PConfusion();
#ifdef OCCT_DEBUG
  std::cout << ") -> (" << t1 << ", " << t2 << ")" << std::endl;
#endif
      
  if ( t1 <= a || t2 >= b ) { // should not be so, but to be sure ..
    return Standard_False;
  }

  // direct construction causes error on osf system.
  gp_Pnt p(0,0,0);
  gp_Dir d(0,0,1);
  gp_Ax3 ax(p, d);
  gp_Pln Pln (ax);
  
  // PTV OCC884
  Handle(Geom_Plane) aPlaneSurf = Handle(Geom_Plane)::DownCast( BRep_Tool::Surface(face) );
  Handle(Geom_Curve) pcurve3d = crv;
  if ( !aPlaneSurf.IsNull() ) {
    Pln =  aPlaneSurf->Pln();
  }
  else
    pcurve3d = GeomAPI::To3d ( c2d, Pln );

  // first segment
  //Handle(Geom_Curve) pcurve3d = GeomAPI::To3d ( c2d, Pln );
  Handle(Geom_TrimmedCurve) trim = new Geom_TrimmedCurve (pcurve3d, a, t1);
  GeomConvert_CompCurveToBSplineCurve connect ( trim );
  
  // null-length segment patch instead of loop
  TColgp_Array1OfPnt Poles(1,2);
  TColStd_Array1OfReal Knots(1,2);
  TColStd_Array1OfInteger Mults(1,2);

  Poles.SetValue(1,trim->Value(t1));
  Knots.SetValue(1,t1);
  Mults.SetValue(1,2);

  trim = new Geom_TrimmedCurve (pcurve3d, t2, b);
  Poles.SetValue(2,trim->Value(t2));
  Knots.SetValue(2,t2);
  Mults.SetValue(2,2);

  Handle(Geom_BSplineCurve) patch = new Geom_BSplineCurve ( Poles, Knots, Mults, 1 );
  if ( ! connect.Add (patch, ::Precision::PConfusion(), Standard_True, Standard_False) )
    return Standard_False;
  
  // last segment
  if ( ! connect.Add (trim, ::Precision::PConfusion(), Standard_True, Standard_False) )
    return Standard_False;
  // PTV OCC884
  // keep created 3d curve
  Handle(Geom_Curve) aNew3dCrv = connect.BSplineCurve();
  
  
  Handle(Geom2d_Curve) bs = GeomAPI::To2d ( aNew3dCrv, Pln );
  if ( bs.IsNull() ) return Standard_False;
  
  // make temp edge and compute tolerance
  BRep_Builder B;

  if(!RemoveLoop3d) { // old variant (not remove loop 3d)
    Standard_Real newtol=0;
    // OCC901
    Standard_Integer nbC2d = howMuchPCurves( E );
    if ( nbC2d <= 1  && !aPlaneSurf.IsNull() )
      B.UpdateEdge ( E, bs, face, 0 );
    else
      if ( ! TryNewPCurve ( E, face, bs, a, b, newtol ) ) return Standard_False;
  
    Standard_Real tol = BRep_Tool::Tolerance ( E );
#ifdef OCCT_DEBUG
    std::cout << "Cut Loop: tol orig " << tol << ", prec " << prec << ", new tol " << newtol << std::endl;
#endif
    if ( newtol > Max ( prec, tol ) ) return Standard_False;
    //:s2  bs = BRep_Tool::CurveOnSurface ( edge, face, a, b );
    if ( Abs ( a - f ) > ::Precision::PConfusion() || // smth strange, cancel
         Abs ( b - l ) > ::Precision::PConfusion() ) return Standard_False;
    // PTV OCC884
    if ( !aPlaneSurf.IsNull() ) {
      B.UpdateEdge ( E, aNew3dCrv, Max (newtol, tol) );
      // OCC901
      if ( ! TryNewPCurve ( E, face, bs, a, b, newtol ) ) return Standard_False;
    }
    B.UpdateEdge ( E, bs, face, newtol );
    B.UpdateVertex ( sae.FirstVertex ( E ), newtol );
    B.UpdateVertex ( sae.LastVertex  ( E ), newtol );
    return Standard_True;
  }

  //:q1
  TopLoc_Location L;
  Handle(Geom_Surface) S = BRep_Tool::Surface(face, L);
  Handle(Geom2dAdaptor_Curve) AC = new Geom2dAdaptor_Curve(c2d);
  Handle(GeomAdaptor_Surface) AS = new GeomAdaptor_Surface(S);
  
  Adaptor3d_CurveOnSurface ACS(AC,AS);
  gp_Pnt P1(ACS.Value(t1));
  gp_Pnt P2(ACS.Value(t2));
  gp_Pnt pcurPnt((P1.X()+P2.X())/2,(P1.Y()+P2.Y())/2,(P1.Z()+P2.Z())/2);
  
  ShapeAnalysis_TransferParametersProj SFTP(E,face);
  Handle(TColStd_HSequenceOfReal) Seq2d = new TColStd_HSequenceOfReal;
  Seq2d->Append(t1);
  Seq2d->Append(t2);
  Seq2d->Append((t1+t2)/2);
  Handle(TColStd_HSequenceOfReal) Seq3d = SFTP.Perform(Seq2d,Standard_False);
  
  Standard_Real dist1 = pcurPnt.Distance(crv->Value(Seq3d->Value(1)));// correting Seq3d already project 
  Standard_Real dist2 = pcurPnt.Distance(crv->Value(Seq3d->Value(2)));
  Standard_Real dist3 = pcurPnt.Distance(crv->Value(Seq3d->Value(3)));
  Standard_Real ftrim,ltrim;
  if(dist3>Max(dist1,dist2)) {
    loopRemoved3d = Standard_False;
  }
  else {
    loopRemoved3d = Standard_True;
  }
  
  Handle(Geom_Curve) bs1;
  
  if (!loopRemoved3d) {
    // create new 3d curve
    ftrim = Seq3d->Value(1);
    ltrim = Seq3d->Value(2);
    ftrim-=dt;
    ltrim+=dt;
    Handle(Geom_TrimmedCurve) trim1 = new Geom_TrimmedCurve (crv, f, ftrim);
    GeomConvert_CompCurveToBSplineCurve connect1 ( trim1 );
    TColgp_Array1OfPnt      Poles1(1,2);
    TColStd_Array1OfReal    Knots1(1,2);
    TColStd_Array1OfInteger Mults1(1,2);
    
    Poles1.SetValue(1,trim1->Value(ftrim));
    Knots1.SetValue(1,ftrim);
    Mults1.SetValue(1,2);
    
    trim1 = new Geom_TrimmedCurve (crv, ltrim, l);
    Poles1.SetValue(2,trim1->Value(ltrim));
    Knots1.SetValue(2,ltrim);
    Mults1.SetValue(2,2);
  
    // create b-spline curve
    Handle(Geom_BSplineCurve) patch1 = new Geom_BSplineCurve ( Poles1, Knots1, Mults1, 1 );
  
    if ( ! connect1.Add (patch1, ::Precision::PConfusion(), Standard_True, Standard_False) )
      return Standard_False;
    
    // last segment
    if ( ! connect1.Add (trim1, ::Precision::PConfusion(), Standard_True, Standard_False) )
      return Standard_False;
    
    bs1 = connect1.BSplineCurve();
    
    if ( bs1.IsNull() )
      return Standard_False;
  }
//  Standard_Real oldtol = BRep_Tool::Tolerance ( E );

  if (!loopRemoved3d)
    B.UpdateEdge ( E, bs1, L, 0. );
  B.UpdateEdge ( E, bs, face, 0. );
  B.Range ( E, face, f, l );
  B.SameRange ( E, Standard_False );

  Handle(ShapeFix_Edge) sfe = new ShapeFix_Edge;
  sfe->FixSameParameter ( E ); 

  return Standard_True;
}

//=======================================================================
//function : RemoveLoop
//purpose  : 
//=======================================================================
static Standard_Boolean RemoveLoop (TopoDS_Edge &E, const TopoDS_Face &face,
				    const IntRes2d_IntersectionPoint &IP2d,
                                    TopoDS_Edge &E1,
                                    TopoDS_Edge &E2)
{
#ifdef OCCT_DEBUG
  std::cout<<"Info: ShapeFix_Wire::FixSelfIntersection : Try insert vertex"<<std::endl;
#endif

  if ( BRep_Tool::IsClosed ( E, face ) ) return Standard_False;
  
  Standard_Real f, l;
  Handle(Geom_Curve) crv = BRep_Tool::Curve ( E, f, l );

  Standard_Real t1 = IP2d.ParamOnFirst();
  Standard_Real t2 = IP2d.ParamOnSecond();
  
  if ( t1 > t2 ) 
  { 
    Standard_Real t = t1; t1 = t2; t2 = t; 
  }

  ShapeAnalysis_Edge sae;
  
  // define vertexes Vfirst , Vlast, Vmid
  TopoDS_Vertex Vfirst,Vlast,Vmid;
  // initialize Vfirst and Vlast
  Vfirst = sae.FirstVertex(E);
  Vlast  = sae.LastVertex(E); 
  
  // find a 2d curve and parameters from edge E
  Standard_Real a, b;
  Handle (Geom2d_Curve) c2d;
  if ( ! sae.PCurve ( E, face, c2d, a, b, Standard_False ) ) 
    return Standard_False;

  // first segment for 2d curve
  Handle(Geom2d_TrimmedCurve) trim1;
  if( (t1-a)>Precision::PConfusion() )
    trim1 = new Geom2d_TrimmedCurve (c2d, a, t1);
  // second segment for 2d curve
  Handle(Geom2d_TrimmedCurve) trim2 = new Geom2d_TrimmedCurve (c2d, t2, b);

//  if ( trim1.IsNull() || trim2.IsNull()  ) 
  if(trim2.IsNull()) 
    return Standard_False;

  TopLoc_Location L;
  Handle (Geom_Surface) S = BRep_Tool::Surface(face, L);
  Handle (Geom2dAdaptor_Curve) AC = new Geom2dAdaptor_Curve(c2d);
  Handle (GeomAdaptor_Surface) AS = new GeomAdaptor_Surface(S); 
  
  Adaptor3d_CurveOnSurface ACS(AC,AS);
  gp_Pnt P1(ACS.Value(t1));
  gp_Pnt P2(ACS.Value(t2));
  gp_Pnt pcurPnt((P1.X()+P2.X())/2,(P1.Y()+P2.Y())/2,(P1.Z()+P2.Z())/2);
  
  // transfer parameters from pcurve to 3d curve
  ShapeAnalysis_TransferParametersProj SFTP(E,face);
  Handle (TColStd_HSequenceOfReal) Seq2d = new TColStd_HSequenceOfReal;
  Seq2d->Append(t1);
  Seq2d->Append(t2);
  Seq2d->Append((t1+t2)/2);
  Handle (TColStd_HSequenceOfReal) Seq3d = SFTP.Perform(Seq2d,Standard_False);
  
  Standard_Real dist1 = pcurPnt.Distance(crv->Value(Seq3d->Value(1)));// correting Seq3d already project 
  Standard_Real dist2 = pcurPnt.Distance(crv->Value(Seq3d->Value(2)));
  Standard_Real dist3 = pcurPnt.Distance(crv->Value(Seq3d->Value(3)));
  Standard_Real ftrim,ltrim;
  if ( dist3 > Max(dist1, dist2)) { // is loop in 3d
    ftrim = Seq3d->Value(1);
    ltrim = Seq3d->Value(2);
  }
  else { // not loop in 3d
    ftrim = Seq3d->Value(3);
    ltrim = Seq3d->Value(3);
  }
  
//  ftrim = Seq3d->Value(1);
//  ltrim = Seq3d->Value(2);
  
  // trim for 3d curve 'crv' with parameters from 'f' to 'l' 
  Handle(Geom_TrimmedCurve) trim3;
  if(!trim1.IsNull())
    trim3 = new Geom_TrimmedCurve (crv, f, ftrim);
  // second segment for 3d curve
  Handle(Geom_TrimmedCurve) trim4 = new Geom_TrimmedCurve (crv, ltrim, l);

//  if ( trim3.IsNull() || trim4.IsNull()  ) 
  if(trim4.IsNull()) 
    return Standard_False;
  
  // create a point for middle vertex
  gp_Pnt pnt1 = crv->Value(ftrim);
  gp_Pnt pnt2 = crv->Value(ltrim);
  gp_Pnt Pmid((pnt1.X()+pnt2.X())/2,(pnt1.Y()+pnt2.Y())/2,(pnt1.Z()+pnt2.Z())/2);
    
  BRep_Builder B;
  
  // create new copies for E1 and E2
  if(!trim1.IsNull())
    E1=TopoDS::Edge(E.EmptyCopied());
  E2=TopoDS::Edge(E.EmptyCopied());
  
  // initialize middle vertex Vmid
  if(trim1.IsNull()) 
    B.MakeVertex(Vmid, pnt2, 0.);
  else
    B.MakeVertex(Vmid, Pmid, 0.);
  
  ShapeBuild_Edge sbe;
  
  // replace verteces for new edges E1 and E2
  if (E.Orientation()== TopAbs_FORWARD)
  {
    if(!E1.IsNull())
      E1=sbe.CopyReplaceVertices(E1,Vfirst,Vmid);
    E2=sbe.CopyReplaceVertices(E2,Vmid, Vlast);
  }
  else 
  {
    if(!E1.IsNull())
      E1=sbe.CopyReplaceVertices(E1,Vmid, Vlast);
    E2=sbe.CopyReplaceVertices(E2,Vfirst, Vmid);
  }
  
  // Update edges by 2d and 3d curves
  Handle(ShapeFix_Edge) mySfe = new ShapeFix_Edge;
  if(!E1.IsNull()) {
    B.UpdateEdge(E1, trim1, face, 0.);
    B.UpdateEdge(E1, trim3, 0.);
    B.Range(E1, f, ftrim);
    B.SameRange(E1,Standard_False);
//    B.SameParameter(E1,Standard_False);
    mySfe->FixSameParameter(E1);
    mySfe->FixVertexTolerance(E1);
  }
  B.UpdateEdge(E2, trim2, face, 0.);
  B.UpdateEdge(E2, trim4, 0.);
  B.Range ( E2,ltrim,l     );
  B.SameRange(E2, Standard_False );
//  B.SameParameter(E2, Standard_False);
  mySfe->FixSameParameter(E2);
  mySfe->FixVertexTolerance(E2);

  return Standard_True;
}


//=======================================================================
//function : FixSelfIntersectingEdge
//purpose  : 
//=======================================================================

Standard_Boolean ShapeFix_Wire::FixSelfIntersectingEdge (const Standard_Integer num) 
{
  myLastFixStatus = ShapeExtend::EncodeStatus ( ShapeExtend_OK );
  if ( ! IsReady() ) return Standard_False;

  // analysis
  IntRes2d_SequenceOfIntersectionPoint points2d;
  TColgp_SequenceOfPnt points3d;
  Handle(ShapeAnalysis_Wire) theAdvAnalyzer = myAnalyzer;
  if (theAdvAnalyzer.IsNull()) return Standard_False;
  theAdvAnalyzer->CheckSelfIntersectingEdge ( num, points2d, points3d ); 
  if ( theAdvAnalyzer->LastCheckStatus ( ShapeExtend_FAIL ) ) {
    myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL1 );
  }
  if ( ! theAdvAnalyzer->LastCheckStatus ( ShapeExtend_DONE ) ) return Standard_False;
  
  // action: increase tolerance of vertex
  
  TopoDS_Edge E = WireData()->Edge ( num >0 ? num : NbEdges() );
  
  ShapeAnalysis_Edge sae;
  TopoDS_Vertex V1 = sae.FirstVertex ( E );
  TopoDS_Vertex V2 = sae.LastVertex ( E );
  Standard_Real tol1 = BRep_Tool::Tolerance ( V1 );
  Standard_Real tol2 = BRep_Tool::Tolerance ( V2 );
  gp_Pnt pnt1 = BRep_Tool::Pnt ( V1 );
  gp_Pnt pnt2 = BRep_Tool::Pnt ( V2 );

  // cycle is to verify fix in case of RemoveLoop
  Standard_Real tolfact = 0.1; // factor for shifting by parameter in RemoveLoop
  Standard_Real f2d = 0., l2d = 0.;
  Handle(Geom2d_Curve) c2d;
  Standard_Real newtol=0.; // = Precision();

  if (myRemoveLoopMode<1) {
    for ( Standard_Integer iter=0; iter < 30; iter++ ) { 
      Standard_Boolean loopRemoved = Standard_False;
      Standard_Real prevFirst = 0 , prevLast = 0; 
      for ( Standard_Integer i=1; i<=points2d.Length(); i++ ) {
        gp_Pnt pint = points3d.Value(i);
        Standard_Real dist21 = pnt1.SquareDistance ( pint );
        Standard_Real dist22 = pnt2.SquareDistance ( pint );
        if ( dist21 < tol1 * tol1 || dist22 < tol2 * tol2 ) continue;
        newtol = 1.001 * Sqrt ( Min ( dist21, dist22 ) ); //:f8

        //:k3 abv 24 Dec 98: BUC50070 #26682 and #30087: try to remove loop
        if ( myGeomMode ) {
          if ( c2d.IsNull() )
            sae.PCurve ( E, Face(), c2d, f2d, l2d, Standard_False );
          Standard_Real firstpar = points2d.Value(i).ParamOnFirst(); 
          Standard_Real lastpar = points2d.Value(i).ParamOnSecond();
          if(firstpar > prevFirst && lastpar < prevLast) continue;
          if ( RemoveLoop (E, Face(), points2d.Value(i), tolfact, 
                           Min( MaxTolerance(), Max(newtol,Precision()) ),
                           myRemoveLoopMode==0 ) ) {
            myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE4 );
            loopRemoved = Standard_True;
            prevFirst = firstpar;
            prevLast = lastpar;
            continue; // repeat of fix on that edge required (to be done by caller)
          }
        }
        if ( newtol < MaxTolerance() ) {
          myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE1 );
          BRep_Builder B;
          if ( dist21 < dist22 ) B.UpdateVertex ( V1, tol1 = newtol );
          else                   B.UpdateVertex ( V2, tol2 = newtol );
        }
        else myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL2 );
      }

      // after RemoveLoop, check that self-intersection disappeared
      if ( loopRemoved ) {
        IntRes2d_SequenceOfIntersectionPoint pnts2d;
        TColgp_SequenceOfPnt pnts3d;
        theAdvAnalyzer->CheckSelfIntersectingEdge ( num, pnts2d, pnts3d );
        if ( ! theAdvAnalyzer->LastCheckStatus ( ShapeExtend_DONE ) ) break;
        //points3d.Append(pnts3d);
        //points2d.Append(pnts2d);
        points3d = pnts3d;
        points2d = pnts2d;
        BRep_Builder B;
        B.UpdateEdge ( E, c2d, Face(), 0. );
        B.Range ( E, Face(), f2d, l2d );
        //newtol+=Precision();
      }
      else {
        break;
      }
    }
  }
  
  //===============================================
  // RemoveLoopMode = 1 , insert vertex 
  //===============================================
  if (myRemoveLoopMode == 1) {
    // after fixing will be nb+1 edges
    Standard_Boolean loopRemoved; 
    // create a sequence of resulting edges
    Handle (TopTools_HSequenceOfShape) TTSS = new TopTools_HSequenceOfShape;
    TopoDS_Edge E2;
    
    loopRemoved = Standard_False;
    //:k3 abv 24 Dec 98: BUC50070 #26682 and #30087: try to remove loop
    if ( myGeomMode ) {
      if ( c2d.IsNull() )
        sae.PCurve ( E, Face(), c2d, f2d, l2d, Standard_False );
      TopoDS_Edge E1;
      if ( RemoveLoop (E, Face(), points2d.Value(1),E1,E2) ) {
        myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE4 );
        loopRemoved = Standard_True;
        if(!E1.IsNull()) {
          TTSS->Append(E1);
          newtol = Max(BRep_Tool::Tolerance(E1),BRep_Tool::Tolerance(E2));
        }
        else
          newtol = BRep_Tool::Tolerance(E2);
      }
    }

    TTSS->Append(E2);
    
    if ( newtol > MaxTolerance() ) 
      myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL2 );
    
    ShapeExtend_WireData sewd;
    for (Standard_Integer i=1 ; i <= TTSS->Length(); i++) {
      sewd.Add(TopoDS::Edge(TTSS->Value(i)));
    }
    if (! Context().IsNull()) {
      Context()->Replace ( E, sewd.Wire() );
      UpdateWire();
    }
    else {
      WireData()->Remove(num >0 ? num : NbEdges());
      WireData()->Add(sewd.Wire(), num >0 ? num : NbEdges());
    }
    if (loopRemoved)
      myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE8 );
    
  }

  if ( LastFixStatus ( ShapeExtend_DONE ) && ! myShape.IsNull() ) {
    SendWarning ( E, Message_Msg ( "FixAdvWire.FixIntersection.MSG5" ) );// Edge was self-intersecting, corrected
  }

  return LastFixStatus ( ShapeExtend_DONE );
}


//=======================================================================
//function : ComputeLocalDeviation
//purpose  : auxiliary
//=======================================================================
static Standard_Real ComputeLocalDeviation (const TopoDS_Edge &edge, 
					    const gp_Pnt &pint,const gp_Pnt &pnt,
					    Standard_Real f, Standard_Real l,
                                            const TopoDS_Face &face )
{
  ShapeAnalysis_Edge sae;
  Handle(Geom_Curve) c3d;
  Standard_Real a, b;
  if ( ! sae.Curve3d ( edge, c3d, a, b, Standard_False ) ) return RealLast();
  
  gp_Lin line ( pint, gp_Vec ( pint, pnt ) );
  
  Handle(Geom2d_Curve) Crv;
  Standard_Real fp,lp;
  if ( sae.PCurve(edge,face,Crv,fp,lp,Standard_False) ) {
    if(Crv->IsKind(STANDARD_TYPE(Geom2d_TrimmedCurve))) {
      Handle(Geom2d_TrimmedCurve) tc = Handle(Geom2d_TrimmedCurve)::DownCast(Crv);
      if(tc->BasisCurve()->IsKind(STANDARD_TYPE(Geom2d_Line))) {
        f = a + (f-fp)*(b-a)/(lp-fp);
        l = a + (l-fp)*(b-a)/(lp-fp);
      }
    }
  }

  const Standard_Integer NSEG = 10;
  Standard_Real step = ( l - f ) / NSEG;
  Standard_Real dev = 0.;
  for ( Standard_Integer i=1; i < NSEG; i++ ) {
    gp_Pnt p = c3d->Value ( f + i * step );
    Standard_Real d = line.Distance ( p );
    if ( dev < d ) dev = d;
  }
  return dev;
}

//=======================================================================
//function : FixIntersectingEdges
//purpose  : 
//=======================================================================

Standard_Boolean ShapeFix_Wire::FixIntersectingEdges (const Standard_Integer num) 
{
  myLastFixStatus = ShapeExtend::EncodeStatus ( ShapeExtend_OK );
  if ( ! IsReady() || NbEdges() <2 ) return Standard_False;

  // analysis
  IntRes2d_SequenceOfIntersectionPoint points2d;
  TColgp_SequenceOfPnt points3d;
  TColStd_SequenceOfReal errors;
  Handle(ShapeAnalysis_Wire) theAdvAnalyzer = myAnalyzer;
  if (theAdvAnalyzer.IsNull()) return Standard_False;
  theAdvAnalyzer->CheckIntersectingEdges ( num, points2d, points3d, errors );
  if ( theAdvAnalyzer->LastCheckStatus ( ShapeExtend_FAIL ) ) {
    myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL1 );
  }
  if ( ! theAdvAnalyzer->LastCheckStatus ( ShapeExtend_DONE ) ) return Standard_False;
  
  //rln 03/02/98: CSR#BUC50004 entity 56 (to avoid later inserting lacking edge)
  //:l0  Standard_Boolean isLacking = myAnalyzer->CheckLacking ( num );

  // action: increase tolerance of vertex
  
  Handle(ShapeExtend_WireData) sbwd = WireData();
  Standard_Integer n2 = ( num >0 ? num  : sbwd->NbEdges() );
  Standard_Integer n1 = ( n2  >1 ? n2-1 : sbwd->NbEdges() );
  TopoDS_Edge E1 = sbwd->Edge(n1);
  TopoDS_Edge E2 = sbwd->Edge(n2);
  if ( !Context().IsNull() )
  {
    E1 = TopoDS::Edge(Context()->Apply(sbwd->Edge(n1))); 
    E2 = TopoDS::Edge(Context()->Apply(sbwd->Edge(n2))); 
  }

  Standard_Boolean isForward1 = ( E1.Orientation() == TopAbs_FORWARD );
  Standard_Boolean isForward2 = ( E2.Orientation() == TopAbs_FORWARD );
  Standard_Real a1, b1, a2, b2;
  BRep_Tool::Range ( E1, Face(), a1, b1 );
  BRep_Tool::Range ( E2, Face(), a2, b2 );

  ShapeAnalysis_Edge sae;
  TopoDS_Vertex Vp = sae.FirstVertex ( E1 );
  TopoDS_Vertex V1 = sae.LastVertex  ( E1 );
  TopoDS_Vertex V2 = sae.FirstVertex ( E2 );
  TopoDS_Vertex Vn = sae.LastVertex  ( E2 );

  Standard_Real tol = BRep_Tool::Tolerance ( V1 );
  gp_Pnt pnt = BRep_Tool::Pnt ( V1 );
  
  Standard_Real prevRange1 = RealLast(), prevRange2 = RealLast();
  Standard_Boolean cutEdge1 = Standard_False, cutEdge2 = Standard_False;
  Standard_Boolean IsCutLine = Standard_False;
  Standard_Boolean isChangedEdge = Standard_False;

  BRep_Builder B;

  Standard_Integer nb = points3d.Length();
  for ( Standard_Integer i=1; i <= nb; i++ ) {
    const IntRes2d_IntersectionPoint &IP = points2d.Value(i);
    Standard_Real param1 = ( num ==1 ? IP.ParamOnSecond() : IP.ParamOnFirst() );
    Standard_Real param2 = ( num ==1 ? IP.ParamOnFirst()  : IP.ParamOnSecond() );
    
    Standard_Real newRange1 = Abs ( ( isForward1 ? a1 : b1 ) - param1 );
    Standard_Real newRange2 = Abs ( ( isForward2 ? b2 : a2 ) - param2 );
    if ( newRange1 > prevRange1 && newRange2 > prevRange2 ) continue;
    
    gp_Pnt pint = points3d.Value(i);
    Standard_Real rad = errors.Value(i);
    Standard_Real newtol = 1.0001 * ( pnt.Distance ( pint ) + rad );

    //GeomAdaptor_Surface& Ads = myAnalyzer->Surface()->Adaptor3d()->ChangeSurface();

    //:r8 abv 12 Apr 99: try increasing tolerance of edge

    Standard_Boolean locMayEdit = myTopoMode;
    // Always try to modify the tolerance firstly as a better solution
    if ( /*! myTopoMode &&*/ newtol > tol )
    {
      Standard_Real te1 = rad + ComputeLocalDeviation (E1, pint, pnt,
        param1, ( isForward1 ? b1 : a1 ), Face() );
      Standard_Real te2 = rad + ComputeLocalDeviation (E2, pint, pnt, 
        ( isForward2 ? a2 : b2 ), param2, Face() );
      Standard_Real maxte = Max ( te1, te2 );
      if ( maxte < MaxTolerance() && maxte < newtol )
      {
        if ( BRep_Tool::Tolerance(E1) < te1 || BRep_Tool::Tolerance(E2) < te2 )
        {
#ifdef OCCT_DEBUG
          std::cout << "Warning: ShapeFix_Wire::FixIE: edges tolerance increased: (" <<
            te1 << ", " << te2 << ") / " << newtol << std::endl;
#endif

          // Make copy of edges.
          if (!Context().IsNull())
          {
             isChangedEdge = Standard_True; // To avoid double copying of vertexes.

            // Intersection point of two base edges.
            ShapeBuild_Edge aSBE;
            TopoDS_Vertex VV1 = Context()->CopyVertex(V1);

            TopoDS_Vertex VVp = Vp;
            TopoDS_Vertex VVn = Vn;
            if (Vp.IsSame(Vn))
            {
              // Should modify only one vertex.
              VVp = Context()->CopyVertex(Vp);
              VVn = VVp;
            }
            else
            {
              VVp = Context()->CopyVertex(Vp);
              VVn = Context()->CopyVertex(Vn);
            }

            TopoDS_Edge EE1 = aSBE.CopyReplaceVertices(E1, VVp, VV1);
            TopoDS_Edge EE2 = aSBE.CopyReplaceVertices(E2, VV1, VVn);

            Context()->Replace(E1, EE1);
            Context()->Replace(E2, EE2);

            UpdateWire();
            E1 = sbwd->Edge(n1);
            E2 = sbwd->Edge(n2);
            Vp = sae.FirstVertex ( E1 );
            V1 = sae.LastVertex  ( E1 );
            V2 = sae.FirstVertex ( E2 );
            Vn = sae.LastVertex  ( E2 );
          }

          B.UpdateEdge ( E1, 1.000001 * te1 );
          B.UpdateVertex ( sae.FirstVertex ( E1 ), 1.000001 * te1 );
          B.UpdateVertex ( sae.LastVertex  ( E1 ), 1.000001 * te1 );
          B.UpdateEdge ( E2, 1.000001 * te2 );
          B.UpdateVertex ( sae.FirstVertex ( E2 ), 1.000001 * te2 );
          B.UpdateVertex ( sae.LastVertex  ( E2 ), 1.000001 * te2 );

          myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE6 );
          locMayEdit = Standard_False;
        }
        newtol = 1.000001 * maxte;
      }
    }
    
    if ( locMayEdit || newtol <= MaxTolerance() )
    {
      prevRange1 = newRange1; 
      prevRange2 = newRange2;
      if ( locMayEdit )
      {
        newtol = 1.0001 * ( pnt.Distance ( pint ) + rad );
        //:j6 abv 7 Dec 98: ProSTEP TR10 r0601_id.stp #57676 & #58586: do not cut edges because of influence on adjacent faces
        ShapeFix_SplitTool aTool;
        
        if ( ! aTool.CutEdge ( E1, ( isForward1 ? a1 : b1 ), param1, Face(), IsCutLine ) ) {
          if ( V1.IsSame ( Vp ) )
            myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE3 );
          else locMayEdit = Standard_False;
        }
        else cutEdge1 = Standard_True; //:h4
        
        if ( ! aTool.CutEdge ( E2, ( isForward2 ? b2 : a2 ), param2, Face(), IsCutLine ) ) {
          if ( V2.IsSame ( Vn ) ) 
            myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE4 );
          else locMayEdit = Standard_False;
        }
        else cutEdge2 = Standard_True; //:h4
      }

      if (  locMayEdit &&
            newRange1 <= prevRange1 && newRange2 <= prevRange2 && //rln 09/01/98
            BRep_Tool::SameParameter ( E1 ) &&
            BRep_Tool::SameParameter ( E2 ) )
      {
        myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE2 );
        pnt = pint;
        if ( tol <= rad ) {
          myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE1 );
          tol = 1.001 * rad;
        }
      }
      else
      {
        if(IsCutLine)
        {
          myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE2 );
          pnt = pint;
          if ( tol <= rad ) {
            myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE1 );
            tol = 1.001 * rad;
          }
        }
        else
        { // else increase tolerance
          if (tol < newtol)
          { //rln 07.04.99 CCI60005-brep.igs
            myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE1 );
            tol = newtol;
          }
        }
      }
    }
    else
    {
      myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL2 );
    }
  }

  if ( ! LastFixStatus ( ShapeExtend_DONE ) ) return Standard_False;

  if (isChangedEdge)
  {
    B.UpdateVertex ( V1, pnt, tol );
    B.UpdateVertex ( V2, pnt, tol );
  }
  else
  {
    if ( !Context().IsNull() )
    {
      if (V1.IsSame(V2) )
      {
        Context()->CopyVertex(V1, pnt, tol);
      }
      else
      {
        Context()->CopyVertex(V1, pnt, tol);
        Context()->CopyVertex(V2, pnt, tol);
      }
    }
    else
    {
      B.UpdateVertex ( V1, pnt, tol );
      B.UpdateVertex ( V2, pnt, tol );
    }
  }

  //:h4: make edges SP (after all cuts: t4mug.stp #3730+#6460)
  if ( cutEdge1 ) 
  {
    if ( !Context().IsNull() )
      E1 = TopoDS::Edge(Context()->Apply(E1));
    myFixEdge->FixSameParameter ( E1 );
  }
  if ( cutEdge2 && !IsCutLine )
  {
    if ( !Context().IsNull() )
      E2 = TopoDS::Edge(Context()->Apply(E2));
    myFixEdge->FixSameParameter ( E2 );
  }
  if ( cutEdge1 || cutEdge2 ) {
    myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE7 );
  }
  if ( ! myShape.IsNull() ) {
    SendWarning ( Message_Msg ( "FixAdvWire.FixIntersection.MSG10" ) );// Edges were intersecting, corrected
  }
  return Standard_True;
}

//=======================================================================
//function : FixIntersectingEdges
//purpose  : 
//=======================================================================
//pdn 17.03.99 fixing non adjacent intersection by increasing tolerance of vertex

Standard_Boolean ShapeFix_Wire::FixIntersectingEdges (const Standard_Integer num1,
						      const Standard_Integer num2)
{
  myLastFixStatus = ShapeExtend::EncodeStatus ( ShapeExtend_OK );
  if ( !IsReady() ) return Standard_False;
  IntRes2d_SequenceOfIntersectionPoint points2d;
  TColgp_SequenceOfPnt points3d;
  TColStd_SequenceOfReal errors;
  Handle(ShapeAnalysis_Wire) theAdvAnalyzer = myAnalyzer;
  if (theAdvAnalyzer.IsNull()) return Standard_False;
  theAdvAnalyzer->CheckIntersectingEdges ( num1, num2, points2d, points3d, errors);
  if ( theAdvAnalyzer->LastCheckStatus ( ShapeExtend_FAIL ) ) {
    myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL1 );
  }
  if ( ! theAdvAnalyzer->LastCheckStatus ( ShapeExtend_DONE ) ) return Standard_False;
  TColgp_Array1OfPnt vertexPoints(1,4);
  TColStd_Array1OfReal vertexTolers(1,4);
  TColStd_Array1OfReal newTolers(1,4);
  TopTools_Array1OfShape vertices(1,4);
  newTolers.Init(0);
  
  Handle(ShapeExtend_WireData) sbwd = WireData();
  Standard_Integer n2 = ( num1 >0 ? num1  : sbwd->NbEdges() );
  Standard_Integer n1 = ( num2  >1 ? num2 : sbwd->NbEdges() );
  if(n1==n2) return Standard_False;
  
  TopoDS_Edge edge1 = sbwd->Edge(n1);
  TopoDS_Edge edge2 = sbwd->Edge(n2);
  
  ShapeAnalysis_Edge sae;
  vertices(1) = sae.FirstVertex(edge1);
  vertices(2) = sae.LastVertex(edge1);
  vertices(3) = sae.FirstVertex(edge2);
  vertices(4) = sae.LastVertex(edge2);
  
  Standard_Integer i; // svv Jan11 2000 : porting on DEC
  for (i = 1; i <=4; i++) {
    vertexPoints(i) = BRep_Tool::Pnt(TopoDS::Vertex(vertices(i)));
    vertexTolers(i) = BRep_Tool::Tolerance(TopoDS::Vertex(vertices(i)));
  }
   
  Standard_Real aNewTolEdge1 = 0.0, aNewTolEdge2 = 0.0;
  Standard_Integer nb = points3d.Length();
  for ( i=1; i <= nb; i++ ) {
    gp_Pnt pint = points3d.Value(i);

    // searching for the nearest vertexies to the intersection point
    Standard_Real aVtx1Param=0., aVtx2Param=0.;
    Standard_Integer aVC1, aVC2;
    Standard_Real aMinDist = RealLast();
    gp_Pnt aNearestVertex;
    Standard_Real aNecessaryVtxTole = 0.0;
    for(aVC1 = 1; aVC1 <= 2; aVC1++) {
      for(aVC2 = 3; aVC2 <= 4; aVC2++) {
      
        Standard_Real aVtxIPDist = pint.Distance(vertexPoints(aVC1));
        Standard_Real aVtxVtxDist = vertexPoints(aVC1).Distance(vertexPoints(aVC2));
        if(aMinDist > aVtxIPDist && aVtxIPDist > aVtxVtxDist) {
          aNecessaryVtxTole = aVtxVtxDist;
          aNearestVertex = vertexPoints(aVC1);
          aMinDist = aVtxIPDist;
          aVtx1Param = BRep_Tool::Parameter(TopoDS::Vertex(vertices(aVC1)),edge1);
          aVtx2Param = BRep_Tool::Parameter(TopoDS::Vertex(vertices(aVC2)),edge2);
        }
      }
    }
    
    // calculation of necessary tolerances of edges
    const IntRes2d_IntersectionPoint &IP = points2d.Value(i);
    Standard_Real param1 = IP.ParamOnFirst(); 
    Standard_Real param2 = IP.ParamOnSecond();  
    Handle(Geom_Curve) aCurve1, aCurve2;
    Standard_Real f,l;
    TopLoc_Location L1, L2;
    aCurve1 = BRep_Tool::Curve(edge1, L1, f, l);
    aCurve2 = BRep_Tool::Curve(edge2, L2, f, l);
    
    // if aMinDist lower than resolution than the intersection point lyes inside the vertex
    if(aMinDist < gp::Resolution())
      continue;
    
    Standard_Real aMaxEdgeTol1 = 0.0, aMaxEdgeTol2 = 0.0;
    if(aMinDist < RealLast() && !aCurve1.IsNull() && !aCurve2.IsNull())
    {
      gp_Lin aLig(aNearestVertex, gp_Vec(aNearestVertex, pint));
      Standard_Integer aPointsC;
      Standard_Real du1 = 0.05*(param1 - aVtx1Param);
      Standard_Real du2 = 0.05*(param2 - aVtx2Param);
      Standard_Real tole1=BRep_Tool::Tolerance(edge1);
      Standard_Real tole2=BRep_Tool::Tolerance(edge2);
      for(aPointsC = 2; aPointsC < 19; aPointsC++)
      {
        Standard_Real u = aVtx1Param + aPointsC * du1;
        gp_Pnt P1 = aCurve1->Value(u);
        P1.Transform(L1.Transformation());
        Standard_Real d1 = aLig.Distance(P1) * 2.0000001;
        if(d1 > tole1 && d1 > aMaxEdgeTol1)
          aMaxEdgeTol1 = d1;

        u = aVtx2Param + aPointsC * du2;
        gp_Pnt P2 = aCurve2->Value(u);
        P2.Transform(L2.Transformation());
        Standard_Real d2 = aLig.Distance(P2) * 2.0000001;
        if(d2 > tole2 && d2 > aMaxEdgeTol2)
          aMaxEdgeTol2 = d2;
      }
      if(aMaxEdgeTol1 == 0.0 && aMaxEdgeTol2 == 0.0) continue;
      // if the vertexies are far than tolerances so 
      // we do not need to increase edge tolerance
      if(aNecessaryVtxTole > Max(aMaxEdgeTol1, tole1) ||
         aNecessaryVtxTole > Max(aMaxEdgeTol2, tole2))
      {
        aMaxEdgeTol1 = 0.0;
        aMaxEdgeTol2 = 0.0;
      }
    }
    
    Standard_Real rad = errors.Value(i);
    Standard_Real finTol = RealLast();
    Standard_Integer rank=1;
    for(Standard_Integer j=1; j<=4; j++) {
      Standard_Real newtol = 1.0001 * ( pint.Distance (vertexPoints(j)) + rad );
      if(newtol<finTol) {
	rank = j;
	finTol = newtol;
      }
    }
    if(finTol <= MaxTolerance()) {
      myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE1);
      if(newTolers(rank) < finTol)
      {
        if(Max(aMaxEdgeTol1, aMaxEdgeTol2) < finTol && (aMaxEdgeTol1 > 0 || aMaxEdgeTol2 > 0))
        {
          aNewTolEdge1 = Max(aNewTolEdge1, aMaxEdgeTol1);
          aNewTolEdge2 = Max(aNewTolEdge2, aMaxEdgeTol2);
        }
        else
        {
          newTolers(rank) = finTol;
        }
      }
    } else {
      myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL2 );
    }
  }
  
  BRep_Builder B;
  // update of tolerances of edges 
  if(aNewTolEdge1 > 0)
  {
    for(i = 1; i <= 2; i++)
      if(aNewTolEdge1 > Max(vertexTolers(i), newTolers(i)))
        newTolers(i) = aNewTolEdge1;
    B.UpdateEdge(edge1, aNewTolEdge1);
  }
  if(aNewTolEdge2 > 0)
  {
    for(i = 3; i <= 4; i++)
      if(aNewTolEdge2 > Max(vertexTolers(i), newTolers(i)))
        newTolers(i) = aNewTolEdge2;
    B.UpdateEdge(edge2, aNewTolEdge2);
  }
    
  // update of tolerances of vertexies 
  for(i = 1; i <=4; i++)
    if(newTolers(i)>0) B.UpdateVertex(TopoDS::Vertex(vertices(i)),newTolers(i));
  
  if ( ! myShape.IsNull() ) {
    SendWarning ( Message_Msg ( "FixAdvWire.FixIntersection.MSG10" ) );// Edges were intersecting, corrected
  }
  return Standard_True;
}

//=======================================================================
//function : FixLacking
//purpose  : Test if two adjucent edges are disconnected in 2d (while connected 
//           in 3d), and in that case either increase tolerance of the vertex or
//           add a new edge (straight in 2d space), in order to close wire in 2d.
//           Returns True if edge was added or tolerance was increased.
//NOTE     : Is to be run after FixDegenerated
//Algorithm: 1. Compute the 2d gap between edges and calculate a tolerance
//              which should have vertex in order to comprise the gap
//              (using GeomAdaptor_Surface); computed value is inctol
//           2. If inctol < tol of vertex, return False (everything is OK)
//           3. If inctol < Precision, just increase tolerance of vertex to inctol
//           4. Else (if both edges are not degenerated) try to add new edge 
//              with straight pcurve (in order to close the gap):
//              a) if flag MayEdit is False
//                 1. if inctol < MaxTolerance, increase tolerance of vertex to inctol
//                 2. else try to add degenerated edge (check that middle point of 
//                    that pcurveis inside the vertex)
//              b) if MayEdit is True
//                 1. try to replace big vertex with two new small vertices 
//                    connected by new edge. This is made if there is a 3d space
//                    between ends of adjacent edges.
//                 2. if inctol < MaxTolerance, increase tolerance of vertex to inctol
//                 3. else add either degenerated or closed edge (if middle point
//                    of a pcurve of a new edge is inside the vertex, then
//		      degenerated edge is added, else new edge is closed).
//           5. If new edge cannot be added, but inctol < MaxTolerance,
//              when increase tolerance of vertex to a value of inctol
//Short list of some internal variables:
// tol    - tolerance of vertex
// tol2d  - tolerance in parametric space of the surface corresponding to 2*tol
// dist2d - distance between ends of pcurves of edges (2d)
// inctol - tolerance required for vertex to close 2d gap (=tol*dist2d/tol2d)
// tol1, tol2 - tolerances of edges, tol0 = tol1 + tol2
// p3d1, p3d2 - ends of 3d curves of edges
//=======================================================================
//:h2 abv 28 May 98: merged modifications by abv 22 Apr 98, gka 27 May 98 
// and pdn 25 May 98 concerning lacking closed or degenerated edges
// Example files: r0501_pe #107813, UKI60107-6 250, UKI60107-3 1577.

//:s2 abv 21 Apr 99: add functionality for bending pcurve
static Standard_Boolean TryBendingPCurve (const TopoDS_Edge &E, const TopoDS_Face &face,
					  const gp_Pnt2d p2d, const Standard_Boolean end,
					  Handle(Geom2d_Curve) &c2d,
                                          Standard_Real &first, Standard_Real &last,
                                          Standard_Real &tol)
{
  ShapeAnalysis_Edge sae;
  if ( ! sae.PCurve ( E, face, c2d, first, last, Standard_False ) ) return Standard_False;
  
  {
  try {
    OCC_CATCH_SIGNALS
    Handle(Geom2d_BSplineCurve) bs;
    if ( c2d->IsKind(STANDARD_TYPE(Geom2d_BSplineCurve)) ) 
      bs = Handle(Geom2d_BSplineCurve)::DownCast(c2d->Copy());
    else // if ( c2d->IsKind(STANDARD_TYPE(Geom2d_Line)) ) 
    {
      Handle(Geom2d_TrimmedCurve) trim = new Geom2d_TrimmedCurve ( c2d, first, last );
      bs = Geom2dConvert::CurveToBSplineCurve ( trim );
    }
    if ( bs.IsNull() ) return Standard_False;
  
    Standard_Real par = ( end ? last : first );
    if ( fabs ( bs->FirstParameter() - par ) < ::Precision::PConfusion() &&
	bs->Multiplicity(1) > bs->Degree() ) bs->SetPole ( 1, p2d );
    else if ( fabs ( bs->LastParameter() - par ) < ::Precision::PConfusion() &&
	     bs->Multiplicity(bs->NbKnots()) > bs->Degree() ) bs->SetPole ( bs->NbPoles(), p2d );
    else {
      bs->Segment ( first, last );
      if (fabs ( bs->FirstParameter() - par ) < ::Precision::PConfusion() &&
	  bs->Multiplicity(1) > bs->Degree()) bs->SetPole ( 1, p2d );
      else if (fabs ( bs->LastParameter() - par ) < ::Precision::PConfusion() &&
	       bs->Multiplicity(bs->NbKnots()) > bs->Degree()) bs->SetPole ( bs->NbPoles(), p2d );
      else return Standard_False;
    }
    c2d = bs;

    if ( ! TryNewPCurve ( E, face, c2d, first, last, tol ) ) return Standard_False;
  }
  catch ( Standard_Failure const& ) {
#ifdef OCCT_DEBUG
    std::cout << "Warning: ShapeFix_Wire::FixLacking: Exception in Geom2d_BSplineCurve::Segment()" << std::endl;
#endif
    return Standard_False;
  }
  }

  return Standard_True;
}


//=======================================================================
//function : FixLacking
//purpose  : 
//=======================================================================

Standard_Boolean ShapeFix_Wire::FixLacking (const Standard_Integer num,
                                            const Standard_Boolean force) 
{
    myLastFixStatus = ShapeExtend::EncodeStatus ( ShapeExtend_OK );
  if ( ! IsReady() ) return Standard_False;

  //=============
  // First phase: analysis whether the problem (gap) exists
  gp_Pnt2d p2d1, p2d2;
  myAnalyzer->CheckLacking ( num, ( force ? Precision() : 0. ), p2d1, p2d2 );
  if ( myAnalyzer->LastCheckStatus ( ShapeExtend_FAIL ) ) {
    myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL1 );
  }
  if ( ! myAnalyzer->LastCheckStatus ( ShapeExtend_DONE ) ) return Standard_False;
  
  //=============
  // Second phase: collection of data necessary for further analysis
  
  Handle(ShapeExtend_WireData) sbwd = WireData();
  Standard_Integer n2 = ( num >0 ? num  : sbwd->NbEdges() );
  Standard_Integer n1 = ( n2  >1 ? n2-1 : sbwd->NbEdges() );
  TopoDS_Edge E1 = sbwd->Edge(n1);
  TopoDS_Edge E2 = sbwd->Edge(n2);
  
  ShapeAnalysis_Edge sae;
  TopoDS_Vertex V1 = sae.LastVertex  ( E1 );
  TopoDS_Vertex V2 = sae.FirstVertex ( E2 );
  Standard_Real tol = Max ( BRep_Tool::Tolerance ( V1 ), BRep_Tool::Tolerance ( V2 ) );
  
  Standard_Real Prec = Precision();
  Standard_Real dist2d = myAnalyzer->MaxDistance2d();
  Standard_Real inctol = myAnalyzer->MaxDistance3d();
  
  TopoDS_Face face = myAnalyzer->Face();
  Handle(ShapeAnalysis_Surface) surf = myAnalyzer->Surface();

  gp_Pnt p3d1, p3d2;
  Standard_Real tol1=::Precision::Confusion(), tol2=::Precision::Confusion(); //SK

  //=============
  //:s2 abv 21 Apr 99: Speculation: try bending pcurves
  Standard_Real bendtol1 = 0., bendtol2 = 0.;
  Handle(Geom2d_Curve) bendc1, bendc2;
  Standard_Real bendf1 = 0., bendl1 = 0., bendf2 = 0., bendl2 = 0.;
  if ( myGeomMode && ! BRep_Tool::IsClosed(E1,face) && ! BRep_Tool::IsClosed(E2,face) ) {
    gp_Pnt2d p2d = 0.5 * ( p2d1.XY() + p2d2.XY() );
    Standard_Boolean ok1 = TryBendingPCurve (E1, face, p2d, E1.Orientation() == TopAbs_FORWARD, 
					     bendc1, bendf1, bendl1, bendtol1);
    Standard_Boolean ok2 = TryBendingPCurve (E2, face, p2d, E2.Orientation() == TopAbs_REVERSED, 
					     bendc2, bendf2, bendl2, bendtol2);
    if ( ok1 && ! ok2 ) {
      bendtol2 = BRep_Tool::Tolerance(E2);
      ok1 = TryBendingPCurve (E1, face, p2d2, E1.Orientation() == TopAbs_FORWARD, 
			      bendc1, bendf1, bendl1, bendtol1);
    }
    else if ( ! ok1 && ok2 ) {
      bendtol1 = BRep_Tool::Tolerance(E1);
      ok2 = TryBendingPCurve (E2, face, p2d1, E2.Orientation() == TopAbs_FORWARD, 
			      bendc2, bendf2, bendl2, bendtol2);
    }
    if ( ! ok1 && ! ok2 ) bendc1.Nullify();
  }
  
  //=============
  // Third phase: analyse how to fix the problem
  
  // selector of solutions
  Standard_Boolean doIncrease  = Standard_False; // increase tolerance
  Standard_Boolean doAddLong   = Standard_False; // add long 3d edge in replacement of a vertex
  Standard_Boolean doAddClosed = Standard_False; // add closed 3d edge
  Standard_Boolean doAddDegen  = Standard_False; // add degenerated edge
  Standard_Boolean doBend      = Standard_False; //:s2 bend pcurves

  // if bending is OK with existing tolerances of edges, take it
  if ( ! bendc1.IsNull() && ! bendc2.IsNull() &&
       ( ( bendtol1 < BRep_Tool::Tolerance(E1) &&
           bendtol2 < BRep_Tool::Tolerance(E2) ) ||
	 ( inctol < Prec && bendtol1 < inctol && bendtol2 < inctol ) ) ) 
       doBend = Standard_True;
  
  // is it OK just to increase tolerance (to a value less than preci)?
  else if ( inctol < Prec ) doIncrease = Standard_True;

  // If increase is not OK or force, try to find other solutions (adding edge)
  else if ( ! BRep_Tool::Degenerated ( E2 ) && ! BRep_Tool::Degenerated ( E1 ) ) {
    
    // analyze the 3d space btw edges: is it enough to add long 3d edge?
    if ( myTopoMode ) {
      Handle(Geom_Curve) c3d;
      Standard_Real a, b;
      if ( ! sae.Curve3d ( E1, c3d, a, b, Standard_True ) ) { // cannot work
	myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL1 );
	return Standard_False; 
      }
      p3d1 = c3d->Value ( b );
      Standard_Real dist2d3d1 = p3d1.Distance ( surf->Value ( p2d1 ) );
      if ( ! sae.Curve3d ( E2, c3d, a, b, Standard_True ) ) { // cannot work
	myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL1 );
	return Standard_False; 
      }
      p3d2 = c3d->Value ( a );
      Standard_Real dist2d3d2 = p3d2.Distance ( surf->Value ( p2d2 ) );

      tol1 = Max ( BRep_Tool::Tolerance ( E1 ), dist2d3d1 );
      tol2 = Max ( BRep_Tool::Tolerance ( E2 ), dist2d3d2 );
      //:c5  Standard_Real tol0 = Max ( tol1 + tol2, thepreci );
      Standard_Real tol0 = tol1 + tol2; //:c5 abv 26 Feb 98: CTS17806 #44418
      Standard_Real dist3d2 = p3d1.SquareDistance ( p3d2 );

      // is it OK to add a long 3d edge?
      if ( ! myAnalyzer->LastCheckStatus ( ShapeExtend_DONE2 ) && //:81 abv 20 Jan 98: don`t add back-going edges (zigzags)
	   dist3d2 > 1.25 * tol0 * tol0 &&
	   ( force || dist3d2 > Prec * Prec || inctol > MaxTolerance() ) ) {
	doAddLong = Standard_True;
      }
    }
    
    //:h6 abv 25 Jun 98: BUC40132 6361: try to increase tol up to MaxTol if not add
    if ( ! doAddLong && inctol < MaxTolerance() && 
	 ! myAnalyzer->Surface()->IsDegenerated ( p2d1, p2d2, 2.*tol, 10. ) ) { //:p7
      if ( ! bendc1.IsNull() && ! bendc2.IsNull() &&
	   bendtol1 < inctol && bendtol2 < inctol ) doBend = Standard_True;
      else doIncrease = Standard_True;
    }
    else 
      
    // else try to add either degenerated or closed edge
    if ( ! doAddLong ) {
      gp_Pnt pV = 0.5 * ( BRep_Tool::Pnt(V1).XYZ() + BRep_Tool::Pnt(V2).XYZ() );
      gp_Pnt pm = myAnalyzer->Surface()->Value ( 0.5 * ( p2d1.XY() + p2d2.XY() ) );

      Standard_Real dist = pV.Distance ( pm );
      if ( dist <= tol ) doAddDegen = Standard_True;
      else if ( myTopoMode ) doAddClosed = Standard_True;
      else if ( dist <= MaxTolerance() ) { //:r7 abv 12 Apr 99: t3d_opt.stp #14245 after S4136
	doAddDegen = Standard_True;
	doIncrease = Standard_True;
	inctol = dist; 
      }
    }
  }

  else if ( !BRep_Tool::Degenerated(E2) && BRep_Tool::Degenerated(E1) ) {
    // create new degenerated edge and replace E1 to new edge
  }
  else if ( BRep_Tool::Degenerated(E2) && !BRep_Tool::Degenerated(E1) ) {
    // create new degenerated edge and replace E2 to new edge
  }
  
  //=============
  // Third phase - do the fixes
  BRep_Builder B;

  // add edge
  if ( doAddLong || doAddDegen || doAddClosed ) {

    // construct new vertices
    TopoDS_Vertex newV1, newV2;
    if ( doAddLong ) {
      newV1 = BRepBuilderAPI_MakeVertex ( p3d1 );
      newV1.Reverse();
      newV2 = BRepBuilderAPI_MakeVertex ( p3d2 );
      B.UpdateVertex ( newV1, 1.001 * tol1 );
      B.UpdateVertex ( newV2, 1.001 * tol2 );
    }
    else {
      newV1 = V1;
      newV2 = V2;
    }

    // prepare new edge
    TopoDS_Edge edge;
    B.MakeEdge ( edge );
    if ( doAddDegen ) B.Degenerated ( edge, Standard_True ); // sln: do it before adding curve
    gp_Vec2d v12 ( p2d1, p2d2 );
    Handle(Geom2d_Line) theLine2d = new Geom2d_Line ( p2d1, gp_Dir2d ( v12 ) );
    B.UpdateEdge ( edge, theLine2d, face, ::Precision::Confusion() );
    B.Range ( edge, face, 0, dist2d );
    B.Add ( edge, newV1.Oriented ( TopAbs_FORWARD ) );
    B.Add ( edge, newV2.Oriented ( TopAbs_REVERSED ) );
    ShapeBuild_Edge sbe;
    if ( ! doAddDegen && ! sbe.BuildCurve3d ( edge ) ) {
      myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL3 );
      return Standard_False; 
    }

    // if long edge is added, replace vertices of adjacent edges
    if ( doAddLong ) {
      
      // replace 1st edge (n1==n2 - special case: wire consists of one edge)
      TopoDS_Edge edge1 = sbe.CopyReplaceVertices ( E1, 
			  ( n1 == n2 ? newV2 : TopoDS_Vertex() ), newV1 );
      sbwd->Set ( edge1, n1 );
      if ( ! Context().IsNull() ) {
	Context()->Replace ( E1, edge1 );
	// actually, this will occur only in context of single face
	// hence, recording to ReShape is rather for tracking modifications
	// than for keeping sharing
	Context()->Replace ( V1, newV1.Oriented ( V1.Orientation() ) );
	if ( ! V1.IsSame ( V2 ) ) { 
	  Context()->Replace ( V2, newV2.Oriented ( V2.Orientation() ) );
	}
      }
      // replace 2nd edge
      if ( n1 != n2 ) {
        TopoDS_Edge edge2 = sbe.CopyReplaceVertices ( E2, newV2, TopoDS_Vertex() );
        sbwd->Set ( edge2, n2 );
	if ( ! Context().IsNull() ) Context()->Replace ( E2, edge2 );
      }
      if ( ! Context().IsNull() ) UpdateWire();
    }

    // insert new edge
    if ( doAddDegen ) {
      myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE3 );
#ifdef OCCT_DEBUG
      std::cout << "Warning: ShapeFix_Wire::FixLacking: degenerated edge added" << std::endl;
#endif
    }
    else if ( ! doAddLong ) {
      myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE4 );
    }
    sbwd->Add ( edge, n2 );
    myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE2 );
  }
  
  // else try to increase tol up to MaxTol
  else if ( inctol > tol && inctol < MaxTolerance() ) {
    if ( ! bendc1.IsNull() && ! bendc2.IsNull() &&
	 bendtol1 < inctol && bendtol2 < inctol ) doBend = Standard_True;
    else doIncrease = Standard_True;
  }
  
  // bend pcurves
  if ( doBend ) { //:s2 abv 21 Apr 99
    B.UpdateEdge ( E1, bendc1, face, bendtol1 );
    B.Range ( E1, face, bendf1, bendl1 );
    B.UpdateEdge ( E2, bendc2, face, bendtol2 );
    B.Range ( E2, face, bendf2, bendl2 );
    B.UpdateVertex ( sae.FirstVertex(E1), bendtol1 );
    B.UpdateVertex ( sae.LastVertex(E1), bendtol1 );
    B.UpdateVertex ( sae.FirstVertex(E2), bendtol2 );
    B.UpdateVertex ( sae.LastVertex(E2), bendtol2 );
    myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE5 );
    //:s3 abv 22 Apr 99: PRO7187 #11534: self-intersection not detected unitil curve is bent (!)
    FixSelfIntersectingEdge ( n1 );
    FixSelfIntersectingEdge ( n2 );
    FixIntersectingEdges ( n2 ); //skl 24.04.2003 for OCC58
#ifdef OCCT_DEBUG
    std::cout << "Info: ShapeFix_Wire::FixLacking: Bending pcurves" << std::endl;
#endif
    myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE5 );
  }
  
  // increase vertex tolerance
  if ( doIncrease ) {
    B.UpdateVertex ( V1, 1.001 * inctol );
    B.UpdateVertex ( V2, 1.001 * inctol );
    myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE1 );
  }

  if ( LastFixStatus ( ShapeExtend_DONE ) ) return Standard_True;

  myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_FAIL2 );
  return Standard_False;
}

//=======================================================================
//function : FixNotchedEdges
//purpose  : 
//=======================================================================

Standard_Boolean ShapeFix_Wire::FixNotchedEdges()
{
  myLastFixStatus = ShapeExtend::EncodeStatus ( ShapeExtend_OK );
  if ( ! IsReady() ) return Standard_False;
  
  Handle(ShapeAnalysis_Wire) theAdvAnalyzer = myAnalyzer;
  TopoDS_Face face = Face();
  if ( ! Context().IsNull() ) UpdateWire();
  Handle(ShapeExtend_WireData) sewd = WireData();
  
  for (Standard_Integer i = 1; i <= NbEdges() && NbEdges() > 2; i++) {
    Standard_Real param;
    Standard_Integer toRemove;
    if(theAdvAnalyzer->CheckNotchedEdges(i,toRemove,param,MinTolerance())){
      Standard_Integer n2 = (i > 0)  ? i : NbEdges();
      Standard_Integer n1 = (n2 > 1) ? n2-1 : NbEdges();
      Standard_Boolean isRemoveFirst = (n1==toRemove);
      Standard_Integer toSplit = (n2==toRemove ? n1 : n2);
      TopoDS_Edge splitE =  sewd->Edge ( toSplit );
      ShapeAnalysis_Edge sae;
      Handle(Geom2d_Curve) c2d;
      Standard_Real a, b;
      sae.PCurve ( splitE, face, c2d, a, b, Standard_True );
      ShapeBuild_Edge sbe;
      TopAbs_Orientation orient = splitE.Orientation();

      // check whether the whole edges should be removed - this is the case
      // when split point coincides with the end of the edge;
      // for closed edges split point may fall at the other end (see issue #0029780)
      if (Abs(param - (isRemoveFirst ? b : a)) <= ::Precision::PConfusion() ||
          (sae.IsClosed3d(splitE) && Abs(param - (isRemoveFirst ? a : b)) <= ::Precision::PConfusion()))
      {
        FixDummySeam(n1);
        // The seam edge is removed from the list. So, need to step back to avoid missing of edge processing
        i--;
      }
      else // perform splitting of the edge and adding to wire
      {
	//pdn check if it is necessary
	if( Abs((isRemoveFirst ? a : b)-param) < ::Precision::PConfusion() ) {
	  continue;
	}
	  
     	Handle(ShapeAnalysis_TransferParametersProj) transferParameters =
          new ShapeAnalysis_TransferParametersProj;
	transferParameters->SetMaxTolerance(MaxTolerance());
	transferParameters->Init(splitE,face);
	Standard_Real first, last;
	if (a < b ) {
	  first = a; 
	  last = b;
	}
	else {
	  first = b; 
	  last = a;
	}
	TopoDS_Vertex Vnew;
	BRep_Builder B;
	B.MakeVertex(Vnew,Analyzer()->Surface()->Value(c2d->Value(param)),::Precision::Confusion());
	TopoDS_Edge wE = splitE;
	wE.Orientation ( TopAbs_FORWARD );
        TopoDS_Shape aTmpShape = Vnew.Oriented(TopAbs_REVERSED); //for porting
	TopoDS_Edge newE1 = sbe.CopyReplaceVertices ( wE, sae.FirstVertex(wE), TopoDS::Vertex(aTmpShape) );
	sbe.CopyPCurves ( newE1, wE  );
	transferParameters->TransferRange(newE1,first,param,Standard_True);
	B.SameRange(newE1,Standard_False);
	B.SameParameter(newE1,Standard_False);
        aTmpShape = Vnew.Oriented(TopAbs_FORWARD);
	TopoDS_Edge newE2 = sbe.CopyReplaceVertices ( wE, TopoDS::Vertex(aTmpShape),sae.LastVertex(wE) );
	sbe.CopyPCurves ( newE2, wE  );
	transferParameters->TransferRange(newE2,param,last,Standard_True);
	B.SameRange(newE2,Standard_False);
	B.SameParameter(newE2,Standard_False);
	
	if ( !Context().IsNull() ) {
	  TopoDS_Wire wire;
	  B.MakeWire(wire);
	  B.Add(wire,newE1);
	  B.Add(wire,newE2);
	  Context()->Replace ( wE, wire );
	}
	
	newE1.Orientation(orient);
	newE2.Orientation(orient);
	if (orient==TopAbs_REVERSED){ TopoDS_Edge tmp = newE2; newE2 = newE1; newE1=tmp;}
	
	Standard_Boolean isRemoveLast = ((n1==NbEdges())&&(n2==1));
	sewd->Set ( newE1, toSplit);
	sewd->Add ( newE2, (toSplit==NbEdges()  ? 0 : toSplit+1));
	
	FixDummySeam(isRemoveLast ? NbEdges() : toRemove);
	myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE2 );
      }
  
      i--;
      if(!Context().IsNull()) //skl 07.03.2002 for OCC180
	UpdateWire();
      myLastFixStatus |= ShapeExtend::EncodeStatus ( ShapeExtend_DONE1 );
    }
  }
  myStatusNotches = myLastFixStatus;
  return LastFixStatus ( ShapeExtend_DONE );
}

//=======================================================================
//function : FixDummySeam
//purpose  : 
//=======================================================================

static void CopyReversePcurves(const TopoDS_Edge& toedge, 
			       const TopoDS_Edge& fromedge,
			       const Standard_Boolean reverse)
{
  TopLoc_Location fromLoc = fromedge.Location();
  TopLoc_Location toLoc = toedge.Location();
  for (BRep_ListIteratorOfListOfCurveRepresentation fromitcr
       ((*((Handle(BRep_TEdge)*)&fromedge.TShape()))->ChangeCurves()); fromitcr.More(); fromitcr.Next()) {
    Handle(BRep_GCurve) fromGC = Handle(BRep_GCurve)::DownCast(fromitcr.Value());
    if ( fromGC.IsNull() ) continue;
    if ( fromGC->IsCurveOnSurface() ) {
      Handle(Geom_Surface) surface = fromGC->Surface();
      TopLoc_Location L = fromGC->Location();
      Standard_Boolean found = Standard_False;
      BRep_ListOfCurveRepresentation& tolist = (*((Handle(BRep_TEdge)*)&toedge.TShape()))->ChangeCurves();
      Handle(BRep_GCurve) toGC;
      for (BRep_ListIteratorOfListOfCurveRepresentation toitcr (tolist); toitcr.More() && !found; toitcr.Next()) {
	toGC = Handle(BRep_GCurve)::DownCast(toitcr.Value());
	if ( toGC.IsNull() || !toGC->IsCurveOnSurface() || 
	    surface != toGC->Surface() || L != toGC->Location() ) continue;
	found = Standard_True;
	break;
      }
      if (!found) {
	Standard_Real fp = fromGC->First();
	Standard_Real lp = fromGC->Last();
	toGC = Handle(BRep_GCurve)::DownCast(fromGC->Copy());
	tolist.Append (toGC);
	Handle(Geom2d_Curve) pcurve = Handle(Geom2d_Curve)::DownCast( fromGC->PCurve()->Copy() );
	if (reverse) {
	  fp = pcurve->ReversedParameter(fp);
	  lp = pcurve->ReversedParameter(lp);
	  pcurve->Reverse();
	  Standard_Real tmp = fp;
	  fp = lp;
	  lp = tmp;
	}
        //bug OCC209 invalid location of pcurve in the edge after copying
	TopLoc_Location newLoc = (fromLoc*L).Predivided(toLoc);
	toGC->SetRange(fp,lp);  
	toGC->PCurve(pcurve);
        toGC->Location(newLoc);
	if ( fromGC->IsCurveOnClosedSurface() ) {
	  pcurve = fromGC->PCurve2();
	  toGC->PCurve2(Handle(Geom2d_Curve)::DownCast(pcurve->Copy()));
	}
      }
    }
  }
}

//=======================================================================
//function : HasNewPCurves
//purpose  : 
//=======================================================================
//  Note:    This function temporarily not used, because adress to it in
//           function FixDummySeam() (see below line 2472) not used too
//
//static Standard_Boolean HasNewPCurves(const TopoDS_Edge& toedge, 
//				      const TopoDS_Edge& fromedge)
//     
//{
//  for (BRep_ListIteratorOfListOfCurveRepresentation fromitcr
//       ((*((Handle(BRep_TEdge)*)&fromedge.TShape()))->ChangeCurves()); fromitcr.More(); fromitcr.Next()) {
//    Handle(BRep_GCurve) fromGC = Handle(BRep_GCurve)::DownCast(fromitcr.Value());
//    if ( fromGC.IsNull() ) continue;
//    if ( fromGC->IsCurveOnSurface() ) {
//      Handle(Geom_Surface) surface = fromGC->Surface();
//      TopLoc_Location L = fromGC->Location();
//      Standard_Boolean found = Standard_False;
//      BRep_ListOfCurveRepresentation& tolist = (*((Handle(BRep_TEdge)*)&toedge.TShape()))->ChangeCurves();
//      Handle(BRep_GCurve) toGC;
//      for (BRep_ListIteratorOfListOfCurveRepresentation toitcr (tolist); toitcr.More() && !found; toitcr.Next()) {
//	toGC = Handle(BRep_GCurve)::DownCast(toitcr.Value());
//	if ( toGC.IsNull() || !toGC->IsCurveOnSurface() || 
//	    surface != toGC->Surface() || L != toGC->Location() )  continue;
//	found = Standard_True;
//	break;
//      }
//      if (!found) 
//	return Standard_True;
//    }
//  }
//  return Standard_False;
//}

//=======================================================================
//function : FixDummySeam
//purpose  : 
//=======================================================================

void ShapeFix_Wire::FixDummySeam(const Standard_Integer num)
{
  ShapeAnalysis_Edge sae;
  ShapeBuild_Edge sbe;
  ShapeBuild_Vertex sbv;
  Standard_Integer num1 = (num == NbEdges()) ? 1 : num+1;
  Handle(ShapeExtend_WireData) sewd = WireData();
  TopoDS_Edge E1 = sewd->Edge(num), E2 = sewd->Edge(num1);
  TopoDS_Vertex V1 = sae.FirstVertex(E1), V2 = sae.LastVertex(E2);
  TopoDS_Vertex Vm = sbv.CombineVertex ( V1, V2, 1.0001 );
  
  //pnd defining if new pcurves exists
  //pdn Temporary not removed
//  Standard_Boolean toRemove = !(HasNewPCurves(E1,E2)||HasNewPCurves(E2,E1));
  Standard_Boolean toRemove = Standard_False;
  
  //creating new edge with pcurves and new vertex
  TopoDS_Vertex Vs = sae.FirstVertex(E2);
  if ( Vs.IsSame ( V1 ) || Vs.IsSame ( V2 ) ) Vs = Vm;
  TopoDS_Edge newEdge = sbe.CopyReplaceVertices ( E2, Vs, Vm );
  CopyReversePcurves(newEdge,E1,E1.Orientation()==E2.Orientation());
  BRep_Builder B;
  B.SameRange(newEdge,Standard_False);
  B.SameParameter(newEdge,Standard_False);

  if ( !Context().IsNull() ) {
    if (toRemove) {
      Context()->Remove ( E2 );
      Context()->Remove ( E1 );
    }
    else {
      Context()->Replace ( E2, newEdge );
      Context()->Replace ( E1, newEdge.Reversed());
    }
    Context()->Replace ( V1, Vm.Oriented(V1.Orientation()) );
    Context()->Replace ( V2, Vm.Oriented(V2.Orientation()) );
  }
 
  Standard_Integer next = ( num1 == NbEdges()) ? 1 : num1+1;
  Standard_Integer prev = ( num > 1) ? num-1 : NbEdges();
  TopoDS_Edge prevE = sewd->Edge(prev), nextE = sewd->Edge(next);
  
  TopoDS_Edge tmpE1=sbe.CopyReplaceVertices( prevE, TopoDS_Vertex(), Vm);
  sewd->Set ( tmpE1,prev );
  if ( !Context().IsNull() ) Context()->Replace ( prevE, tmpE1);
  
  tmpE1  =  sbe.CopyReplaceVertices ( nextE, Vm, TopoDS_Vertex());
  sewd->Set ( tmpE1,next );
  if ( !Context().IsNull() ) Context()->Replace ( nextE, tmpE1);
  
  //removing edges from wire
  Standard_Integer n1, n2;
  if ( num < num1 ) {
    n1 = num; n2 = num1;
  } else {
    n1 = num1; n2 = num;
  }
  sewd->Remove(n2);
  sewd->Remove(n1);
}

//=======================================================================
//function : UpdateWire
//purpose  : 
//=======================================================================

void ShapeFix_Wire::UpdateWire () 
{
  Handle(ShapeExtend_WireData) sbwd = WireData();
  for ( Standard_Integer i=1; i <= sbwd->NbEdges(); i++ ) {
    TopoDS_Edge E = sbwd->Edge(i);
    TopoDS_Shape S = Context()->Apply ( E );
    if ( S == E ) continue;
    for ( TopExp_Explorer exp(S,TopAbs_EDGE); exp.More(); exp.Next() )
      sbwd->Add ( exp.Current(), i++ );
    sbwd->Remove ( i-- );
  }
}

//=======================================================================
//function : FixTails
//purpose  :
//=======================================================================
Standard_Boolean ShapeFix_Wire::FixTails()
{
  if (myMaxTailWidth < 0 || !IsReady())
  {
    return Standard_False;
  }

  myLastFixStatus = ShapeExtend::EncodeStatus(ShapeExtend_OK);
  if (!Context().IsNull())
  {
    UpdateWire();
  }
  Handle(ShapeExtend_WireData) aSEWD = WireData();
  Standard_Integer aECount = NbEdges(), aENs[] = {aECount, 1};
  Standard_Boolean aCheckAngle = Standard_True;
  while (aECount >= 2 && aENs[1] <= aECount)
  {
    const TopoDS_Edge aEs[] = {aSEWD->Edge(aENs[0]), aSEWD->Edge(aENs[1])};
    TopoDS_Edge aEParts[2][2];
    if (!myAnalyzer->CheckTail(aEs[0], aEs[1],
      aCheckAngle ? myMaxTailAngleSine : -1, myMaxTailWidth, MaxTolerance(),
      aEParts[0][0], aEParts[0][1], aEParts[1][0], aEParts[1][1]))
    {
      aENs[0] = aENs[1]++;
      aCheckAngle = Standard_True;
      continue;
    }

    // Provide not less than 1 edge in the result wire.
    Standard_Integer aSplitCounts[] =
      {aEParts[0][1].IsNull() ? 0 : 1, aEParts[1][1].IsNull() ? 0 : 1};
    const Standard_Integer aRemoveCount =
      (aEParts[0][0].IsNull() ? 0 : 1) + (aEParts[1][0].IsNull() ? 0 : 1);
    if (aECount + aSplitCounts[0] + aSplitCounts[1] < 1 + aRemoveCount)
    {
      aENs[0] = aENs[1]++;
      aCheckAngle = Standard_True;
      continue;
    }

    // Split the edges.
    for (Standard_Integer aEI = 0; aEI < 2; ++aEI)
    {
      if (aSplitCounts[aEI] == 0)
      {
        continue;
      }

      // Replace the edge by the wire of its parts in the shape.
      const TopoDS_Edge aE = aEs[aEI];
      if (!Context().IsNull())
      {
        TopoDS_Wire aEWire;
        BRep_Builder().MakeWire(aEWire);
        BRep_Builder().Add(aEWire, aEParts[aEI][0]);
        BRep_Builder().Add(aEWire, aEParts[aEI][1]);
        TopoDS_Edge aFE = TopoDS::Edge(aE.Oriented(TopAbs_FORWARD));
        Context()->Replace(aFE, aEWire);
      }

      // Replace the edge by its parts in the edge wire.
      const TopAbs_Orientation aOrient = aE.Orientation();
      aEParts[aEI][0].Orientation(aOrient);
      aEParts[aEI][1].Orientation(aOrient);
      const Standard_Integer aFirstPI = (aOrient != TopAbs_REVERSED) ? 0 : 1;
      const Standard_Integer aAdd =
        (aEI == 0 || aENs[1] < aENs[0]) ? 0 : aSplitCounts[0];
      aSEWD->Set(aEParts[aEI][aFirstPI], aENs[aEI] + aAdd);
      aSEWD->Add(aEParts[aEI][1 - aFirstPI], aENs[aEI] + 1 + aAdd);
    }

    // Remove the tail.
    if (aRemoveCount == 2)
    {
      aCheckAngle = Standard_True;
      FixDummySeam(aENs[0] + aSplitCounts[0] +
        ((aENs[0] < aENs[1]) ? 0 : aSplitCounts[1]));
      if (!Context().IsNull())
      {
        UpdateWire();
      }
      myLastFixStatus |= ShapeExtend::EncodeStatus(ShapeExtend_DONE);

      if (aSplitCounts[0] + aSplitCounts[1] == 2)
      {
        aENs[0] = aENs[1]++;
        continue;
      }

      if (aSplitCounts[0] == aSplitCounts[1])
      {
        aECount -= 2;
        if (aENs[1] >= 3)
        {
          --aENs[0];
          --aENs[1];
        }
        else
        {
          aENs[0] = aECount;
          aENs[1] = 1;
        }
        aCheckAngle = Standard_False;
      }
      else
      {
        --aECount;
        if (aSplitCounts[0] != 0)
        {
          aENs[0] = (aENs[0] <= aECount) ? aENs[0] : aECount;
        }
        else
        {
          if (aENs[1] >= 3)
          {
            --aENs[0];
            --aENs[1];
          }
          else
          {
            aENs[0] = aECount;
            aENs[1] = 1;
          }
        }
      }
    }
    else
    {
      aCheckAngle = Standard_False;
      --aECount;
      const Standard_Integer aRI = aEParts[0][0].IsNull() ? 1 : 0;
      if (aSplitCounts[aRI] != 0)
      {
        if (aRI == 0)
        {
          if (aENs[1] >= 3)
          {
            --aENs[0];
            --aENs[1];
          }
          else
          {
            aENs[0] = aECount;
            aENs[1] = 1;
          }
        }
        else
        {
          aENs[0] = (aENs[1] > 1) ? aENs[0] : aECount;
        }
      }
      aSEWD->Remove(aENs[aRI] + ((aRI != 0 || aSplitCounts[0] == 0) ? 0 : 1));
      if (!Context().IsNull())
      {
        Context()->Remove(aEs[aRI].Oriented(TopAbs_FORWARD));
        UpdateWire();
      }
      myLastFixStatus |= ShapeExtend::EncodeStatus(ShapeExtend_DONE);
    }
  }
  myStatusNotches = myLastFixStatus;
  return ShapeExtend::DecodeStatus(myLastFixStatus, ShapeExtend_DONE);
}
