[occt.git] / src / BRepOffset / BRepOffset_Inter3d.cxx

// Created on: 1996-09-03
// Created by: Yves FRICAUD
// Copyright (c) 1996-1999 Matra Datavision
// 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.

//  Modified by skv - Fri Dec 26 12:20:14 2003 OCC4455

#include <BRep_Builder.hxx>
#include <BRep_Tool.hxx>
#include <BRepAdaptor_Curve.hxx>
#include <BRepAlgo_AsDes.hxx>
#include <BRepAlgo_Image.hxx>
#include <BRepLib_MakeVertex.hxx>
#include <BRepOffset_Analyse.hxx>
#include <BRepOffset_DataMapOfShapeOffset.hxx>
#include <BRepOffset_Inter3d.hxx>
#include <BRepOffset_Interval.hxx>
#include <BRepOffset_ListOfInterval.hxx>
#include <BRepOffset_Offset.hxx>
#include <BRepOffset_Tool.hxx>
#include <Extrema_ExtPC.hxx>
#include <GeomAPI_ProjectPointOnCurve.hxx>
#include <Precision.hxx>
#include <TopExp.hxx>
#include <TopExp_Explorer.hxx>
#include <TopoDS.hxx>
#include <TopoDS_Compound.hxx>
#include <TopoDS_Edge.hxx>
#include <TopoDS_Face.hxx>
#include <TopoDS_Shape.hxx>
#include <TopoDS_Vertex.hxx>
#include <TopOpeBRepTool_BoxSort.hxx>
#include <TopTools_IndexedMapOfShape.hxx>
#include <TopTools_ListIteratorOfListOfShape.hxx>
#include <TopTools_MapIteratorOfMapOfShape.hxx>
#include <TopTools_MapOfShape.hxx>
//
#include <BOPTools_AlgoTools.hxx>

//=======================================================================
//function : BRepOffset_Inter3d
//purpose  : 
//=======================================================================
BRepOffset_Inter3d::BRepOffset_Inter3d(const Handle(BRepAlgo_AsDes)& AsDes, 
                                       const TopAbs_State            Side ,
                                       const Standard_Real           Tol)
:myAsDes(AsDes),
mySide(Side),
myTol(Tol)
{
}


//=======================================================================
//function : ExtentEdge
//purpose  : 
//=======================================================================

static void ExtentEdge(const TopoDS_Face& /*F*/,
                       const TopoDS_Edge& E,
                       TopoDS_Edge& NE) 
{
  TopoDS_Shape aLocalShape = E.EmptyCopied();
  NE = TopoDS::Edge(aLocalShape); 
//  NE = TopoDS::Edge(E.EmptyCopied()); 
  

  // Enough for analytic edges, in general case reconstruct the 
  // geometry of the edge recalculating the intersection of surfaces.  

  NE.Orientation(TopAbs_FORWARD);
  Standard_Real f,l;
  BRep_Tool::Range(E,f,l);
  Standard_Real length = l-f;
  f -=  100*length;
  l +=  100*length;

  BRep_Builder B;
  B.Range(NE,f,l);
  BRepAdaptor_Curve CE(E);
  TopoDS_Vertex V1 = BRepLib_MakeVertex(CE.Value(f));
  TopoDS_Vertex V2 = BRepLib_MakeVertex(CE.Value(l));
  B.Add(NE,V1.Oriented(TopAbs_FORWARD));
  B.Add(NE,V2.Oriented(TopAbs_REVERSED));
  NE.Orientation(E.Orientation());

}

//=======================================================================
//function : SelectEdge
//purpose  : 
//=======================================================================
static void SelectEdge (const TopoDS_Shape& theS,
                        TopTools_ListOfShape& theLE)
{
  Standard_Real aT1, aT2, aDist, aDistMin;
  TopExp_Explorer aExp;
  TopTools_ListIteratorOfListOfShape aIt;
  GeomAPI_ProjectPointOnCurve aProjPC;
  gp_Pnt aPE1, aPE2;
  TopoDS_Edge aRE;
  //
  aDistMin = RealLast();
  //
  aIt.Initialize(theLE);
  for (; aIt.More(); aIt.Next()) {
    const TopoDS_Edge& aE = *(TopoDS_Edge*)&aIt.Value();
    //
    const Handle(Geom_Curve)& aC = BRep_Tool::Curve(aE, aT1, aT2);
    //
    aProjPC.Init(aC, aT1, aT2);
    aPE1 = aC->Value(aT1);
    aPE2 = aC->Value(aT2);
    //
    aDist = 0.;
    aExp.Init(theS, TopAbs_VERTEX);
    for (; aExp.More(); aExp.Next()) {
      const TopoDS_Vertex& aV = *(TopoDS_Vertex*)&aExp.Current();
      const gp_Pnt aP = BRep_Tool::Pnt(aV);
      //
      aProjPC.Perform(aP);
      if (aProjPC.NbPoints()) {
        aDist += aProjPC.LowerDistance();
      }
      else {
        aDist += Min(aP.Distance(aPE1), aP.Distance(aPE2));
      }
    }
    //
    if (aDist < aDistMin) {
      aDistMin = aDist;
      aRE = aE;
    }
  }
  //
  theLE.Clear();
  theLE.Append(aRE);
}

//=======================================================================
//function : CompletInt
//purpose  : 
//=======================================================================

void BRepOffset_Inter3d::CompletInt(const TopTools_ListOfShape& SetOfFaces,
                                    const BRepAlgo_Image&     InitOffsetFace)
{
  //---------------------------------------------------------------
  // Calculate the intersections of offset faces 
  // Distinction of intersection between faces // tangents.
  //---------------------------------------------------------------
  TopoDS_Face                        F2;
  TopTools_ListIteratorOfListOfShape it;

  //---------------------------------------------------------------
  // Construction of bounding boxes
  //---------------------------------------------------------------
  TopOpeBRepTool_BoxSort BOS;
  BRep_Builder B;
  TopoDS_Compound CompOS;
  B.MakeCompound(CompOS);
  
  for (it.Initialize(SetOfFaces); it.More(); it.Next()) {
    const TopoDS_Shape& OS = it.Value();
    B.Add(CompOS,OS);
  }
  BOS.AddBoxesMakeCOB(CompOS,TopAbs_FACE);

  //---------------------------
  // Intersection of faces // 
  //---------------------------
  for (it.Initialize(SetOfFaces); it.More(); it.Next()) {
    const TopoDS_Face& F1  = TopoDS::Face(it.Value());
    TColStd_ListIteratorOfListOfInteger itLI = BOS.Compare(F1);
    for (; itLI.More(); itLI.Next()) {
      F2     = TopoDS::Face(BOS.TouchedShape(itLI));
      FaceInter(F1,F2,InitOffsetFace);
    }
  }
}


//=======================================================================
//function : CompletInt
//purpose  : 
//=======================================================================

void BRepOffset_Inter3d::FaceInter(const TopoDS_Face& F1,
                                   const TopoDS_Face& F2,
                                   const BRepAlgo_Image&     InitOffsetFace)
{
  TopTools_ListOfShape LInt1, LInt2;
  TopoDS_Edge NullEdge;

  if (F1.IsSame(F2)) return;
  if (IsDone(F1,F2)) return;
  const TopoDS_Shape& InitF1 = InitOffsetFace.ImageFrom(F1);
  const TopoDS_Shape& InitF2 = InitOffsetFace.ImageFrom(F2);
  Standard_Boolean InterPipes = (InitF2.ShapeType() == TopAbs_EDGE &&
                                 InitF1.ShapeType() == TopAbs_EDGE );
  Standard_Boolean InterFaces = (InitF1.ShapeType() == TopAbs_FACE && 
                                 InitF2.ShapeType() == TopAbs_FACE);
  TopTools_ListOfShape LE,LV;
  LInt1.Clear(); LInt2.Clear(); 
  if (BRepOffset_Tool::FindCommonShapes(F1,F2,LE,LV) ||
      myAsDes->HasCommonDescendant(F1,F2,LE)) {
    //-------------------------------------------------
    // F1 and F2 share shapes.
    //-------------------------------------------------
    if ( LE.IsEmpty() && !LV.IsEmpty()) {
      if (InterPipes) {
        //----------------------
        // tubes share a vertex.
        //----------------------
        const TopoDS_Edge& EE1 = TopoDS::Edge(InitF1);
        const TopoDS_Edge& EE2 = TopoDS::Edge(InitF2);
        TopoDS_Vertex VE1[2],VE2[2];
        TopExp::Vertices(EE1,VE1[0],VE1[1]);
        TopExp::Vertices(EE2,VE2[0],VE2[1]);
        TopoDS_Vertex V;
        for (Standard_Integer i = 0 ; i < 2; i++) {
          for (Standard_Integer j = 0 ; j < 2; j++) {
            if (VE1[i].IsSame(VE2[j])) {
              V = VE1[i];
            }
          }
        }
        if (!InitOffsetFace.HasImage(V)) { //no sphere
          BRepOffset_Tool::PipeInter(F1,F2,LInt1,LInt2,mySide);
        }                
      }
      else {
        //--------------------------------------------------------
        // Intersection having only common vertices
        // and supports having common edges.
        // UNSUFFICIENT, but a larger criterion shakes too
        // many sections.
        //--------------------------------------------------------
        if (InterFaces) {
          if (BRepOffset_Tool::FindCommonShapes(TopoDS::Face(InitF1),
                                                TopoDS::Face(InitF2),LE,LV)) {
            if (!LE.IsEmpty()) {
              BRepOffset_Tool::Inter3D (F1,F2,LInt1,LInt2,mySide,NullEdge);
            }
          }
          else {
            BRepOffset_Tool::Inter3D(F1,F2,LInt1,LInt2,mySide,NullEdge);
          }
        }
      }
    }
  }
  else {
    if (InterPipes) {
      BRepOffset_Tool::PipeInter(F1,F2,LInt1,LInt2,mySide);
    }
    else {
      BRepOffset_Tool::Inter3D (F1,F2,LInt1,LInt2,mySide,NullEdge);
    }
  }
  Store (F1,F2,LInt1,LInt2);
}


//=======================================================================
//function : ConnexIntByArc
//purpose  : 
//=======================================================================

void BRepOffset_Inter3d::ConnexIntByArc(const TopTools_ListOfShape& /*SetOfFaces*/, 
                                        const TopoDS_Shape&         ShapeInit, 
                                        const BRepOffset_Analyse&   Analyse, 
                                        const BRepAlgo_Image&       InitOffsetFace)
{
  BRepOffset_Type    OT   = BRepOffset_Concave;
  if (mySide == TopAbs_OUT) OT   = BRepOffset_Convex;
  TopExp_Explorer                Exp(ShapeInit,TopAbs_EDGE);
  TopTools_ListOfShape           LInt1,LInt2;
  TopoDS_Face                    F1,F2;
  TopoDS_Edge                    NullEdge;

  //---------------------------------------------------------------------
  // etape 1 : Intersection of faces // corresponding to the initial faces 
  //           separated by a concave edge if offset > 0, otherwise convex.
  //---------------------------------------------------------------------  
  for (; Exp.More(); Exp.Next()) {
    const TopoDS_Edge&               E = TopoDS::Edge(Exp.Current());
    const BRepOffset_ListOfInterval& L = Analyse.Type(E);
    if (!L.IsEmpty() && L.First().Type() == OT) {
      //-----------------------------------------------------------
      // edge is of the proper type , return adjacent faces.
      //-----------------------------------------------------------
      const TopTools_ListOfShape& Anc = Analyse.Ancestors(E);
      if (Anc.Extent() == 2) {
        F1 = TopoDS::Face(InitOffsetFace.Image(Anc.First()).First());
        F2 = TopoDS::Face(InitOffsetFace.Image(Anc.Last ()).First());
        if (!IsDone(F1,F2)) {
          BRepOffset_Tool::Inter3D (F1,F2,LInt1,LInt2,mySide,E,Standard_True);
          Store (F1,F2,LInt1,LInt2);
        }
      }          
    }
  }
  //---------------------------------------------------------------------
  // etape 2 : Intersections of tubes sharing a vertex without sphere with:
  //           - tubes on each other edge sharing the vertex
  //           - faces containing an edge connected to vertex that has no tubes.
  //---------------------------------------------------------------------
  TopoDS_Vertex                      V[2];
  TopTools_ListIteratorOfListOfShape it; 
  
  for (Exp.Init(ShapeInit,TopAbs_EDGE); Exp.More(); Exp.Next()) {
    const TopoDS_Edge& E1 = TopoDS::Edge(Exp.Current());
    if (InitOffsetFace.HasImage(E1)) {
      //---------------------------
      // E1 generated a tube.
      //---------------------------
      F1 = TopoDS::Face(InitOffsetFace.Image(E1).First());;
      TopExp::Vertices(E1,V[0],V[1]);
      const TopTools_ListOfShape& AncE1 = Analyse.Ancestors(E1);
      
      for (Standard_Integer i = 0; i < 2; i++) {
        if (!InitOffsetFace.HasImage(V[i])) {
          //-----------------------------
          // the vertex has no sphere.
          //-----------------------------
          const TopTools_ListOfShape& Anc     = Analyse.Ancestors(V[i]);
          TopTools_ListOfShape TangOnV;
          Analyse.TangentEdges(E1,V[i],TangOnV);
          TopTools_MapOfShape MTEV;
          for (it.Initialize(TangOnV); it.More(); it.Next()) {
            MTEV.Add(it.Value());
          }
          for (it.Initialize(Anc); it.More(); it.Next()) {
            const TopoDS_Edge& E2 = TopoDS::Edge(it.Value());
//  Modified by skv - Fri Jan 16 16:27:54 2004 OCC4455 Begin
//            if (E1.IsSame(E2) || MTEV.Contains(E2)) continue;
            Standard_Boolean isToSkip = Standard_False;

            if (!E1.IsSame(E2)) {
              const BRepOffset_ListOfInterval& aL = Analyse.Type(E2);

              isToSkip = (MTEV.Contains(E2) && 
                          (aL.IsEmpty() ||
                          (!aL.IsEmpty() && aL.First().Type() != OT)));
            }

            if (E1.IsSame(E2) || isToSkip)
              continue;
//  Modified by skv - Fri Jan 16 16:27:54 2004 OCC4455 End
            if (InitOffsetFace.HasImage(E2)) {
              //-----------------------------
              // E2 generated a tube.
              //-----------------------------
              F2 = TopoDS::Face(InitOffsetFace.Image(E2).First());        
              if (!IsDone(F1,F2)) {
                //---------------------------------------------------------------------
                // Intersection tube/tube if the edges are not tangent (AFINIR).
                //----------------------------------------------------------------------
                BRepOffset_Tool::PipeInter (F1,F2,LInt1,LInt2,mySide);
                Store (F1,F2,LInt1,LInt2);
              }
            }
            else {
              //-------------------------------------------------------
              // Intersection of the tube of E1 with faces //
              // to face containing E2 if they are not tangent
              // to the tube or if E2 is not a tangent edge.
              //-------------------------------------------------------
              const BRepOffset_ListOfInterval& L = Analyse.Type(E2);
               if (!L.IsEmpty() && L.First().Type() == BRepOffset_Tangent) {
                continue;
              }
              const TopTools_ListOfShape& AncE2        = Analyse.Ancestors(E2);
              Standard_Boolean            TangentFaces = Standard_False;
              if (AncE2.Extent() == 2) {
                TopoDS_Face InitF2 = TopoDS::Face(AncE2.First ());
                TangentFaces = (InitF2.IsSame(AncE1.First()) || 
                                InitF2.IsSame(AncE1.Last()));
                if (!TangentFaces) {
                  F2 = TopoDS::Face(InitOffsetFace.Image(InitF2).First());
                  if (!IsDone(F1,F2)) {
                    BRepOffset_Tool::Inter3D (F1,F2,LInt1,LInt2,mySide,NullEdge);
                    Store (F1,F2,LInt1,LInt2);
                  }
                }
                InitF2 = TopoDS::Face(AncE2.Last ());
                TangentFaces = (InitF2.IsSame(AncE1.First()) || 
                                InitF2.IsSame(AncE1.Last()));
                if (!TangentFaces) {
                  F2 = TopoDS::Face(InitOffsetFace.Image(InitF2).First());
                  if (!IsDone(F1,F2)) {
                    BRepOffset_Tool::Inter3D (F1,F2,LInt1,LInt2,mySide,NullEdge);
                    Store (F1,F2,LInt1,LInt2);
                  }
                }
              }
            }
          }
        }
      }
    }
  }
}


//=======================================================================
//function : ConnexIntByInt
//purpose  : 
//=======================================================================

void BRepOffset_Inter3d::ConnexIntByInt
(const TopoDS_Shape&                    SI,
 const BRepOffset_DataMapOfShapeOffset& MapSF,
 const BRepOffset_Analyse&              Analyse,
 TopTools_DataMapOfShapeShape&          MES,
 TopTools_DataMapOfShapeShape&          Build,
 TopTools_ListOfShape&                  Failed,
 const Standard_Boolean                 bIsPlanar)
{
  //TopExp_Explorer Exp(SI,TopAbs_EDGE);
  TopTools_IndexedMapOfShape VEmap;
  TopTools_IndexedDataMapOfShapeListOfShape aMVF;
  TopoDS_Face     F1,F2,OF1,OF2,NF1,NF2;
  TopAbs_State    CurSide = mySide;
  BRep_Builder    B;
  Standard_Boolean bEdge;
  Standard_Integer i, aNb;
  TopTools_ListIteratorOfListOfShape it, it1, itF1, itF2;
  //
  TopExp::MapShapes(SI, TopAbs_EDGE  , VEmap);
  // map the shape for vertices
  if (bIsPlanar) {
    TopExp::MapShapes(SI, TopAbs_VERTEX, VEmap);
    //
    // make vertex-faces connexity map with unique ancestors
    // TopExp::MapShapesAndAncestors(SI, TopAbs_VERTEX, TopAbs_FACE, aMVF);
    TopExp_Explorer aExpF(SI, TopAbs_FACE);
    for (; aExpF.More(); aExpF.Next()) {
      const TopoDS_Shape& aF = aExpF.Current();
      //
      TopExp_Explorer aExpV(aF, TopAbs_VERTEX);
      for (; aExpV.More(); aExpV.Next()) {
        const TopoDS_Shape& aV = aExpV.Current();
        //
        TopTools_ListOfShape *pLF = aMVF.ChangeSeek(aV);
        if (!pLF) {
          pLF = &aMVF(aMVF.Add(aV, TopTools_ListOfShape()));
          pLF->Append(aF);
          continue;
        }
        //
        TopTools_ListIteratorOfListOfShape aItLF(*pLF);
        for (; aItLF.More(); aItLF.Next()) {
          if (aItLF.Value().IsSame(aF)) {
            break;
          }
        }
        if (!aItLF.More()) {
          pLF->Append(aF);
        }
      }
    }
  }
  //
  TopTools_DataMapOfShapeListOfShape aDMVLF1, aDMVLF2, aDMIntFF;
  TopTools_IndexedDataMapOfShapeListOfShape aDMIntE;
  //
  if (bIsPlanar) {
    aNb = VEmap.Extent();
    for (i = 1; i <= aNb; ++i) {
      const TopoDS_Shape& aS = VEmap(i);
      if (aS.ShapeType() != TopAbs_VERTEX) {
        continue;
      }
      //
      // faces connected by the vertex
      const TopTools_ListOfShape& aLF = aMVF.FindFromKey(aS);
      if (aLF.Extent() < 2) {
        continue;
      }
      // build lists of faces connected to the same vertex by looking for
      // the pairs in which the vertex is alone (not connected to shared edges)
      TopTools_ListOfShape aLF1, aLF2;
      //
      it.Initialize(aLF);
      for (; it.More(); it.Next()) {
        const TopoDS_Shape& aFV1 = it.Value();
        //
        // get edges of first face connected to current vertex
        TopTools_MapOfShape aME;
        TopExp_Explorer aExp(aFV1, TopAbs_EDGE);
        for (; aExp.More(); aExp.Next()) {
          const TopoDS_Shape& aE = aExp.Current();
          TopoDS_Iterator aItV(aE);
          for (; aItV.More(); aItV.Next()) {
            if (aS.IsSame(aItV.Value())) {
              aME.Add(aE);
              break;
            }
          }
        }
        //
        // get to the next face in the list
        it1 = it;
        for (it1.Next(); it1.More(); it1.Next()) {
          const TopoDS_Shape& aFV2 = it1.Value();
          //
          aExp.Init(aFV2, TopAbs_EDGE);
          for (; aExp.More(); aExp.Next()) {
            const TopoDS_Shape& aEV2 = aExp.Current();
            if (aME.Contains(aEV2)) {
              break;
            }
          }
          //
          if (!aExp.More()) {
            // faces share only vertex - make pair for intersection
            aLF1.Append(aFV1);
            aLF2.Append(aFV2);
          }
        }
      }
      //
      if (aLF1.Extent()) {
        aDMVLF1.Bind(aS, aLF1);
        aDMVLF2.Bind(aS, aLF2);
      }
    }
  }
  //
  aNb = VEmap.Extent();
  for (i = 1; i <= aNb; ++i) {
    const TopoDS_Shape& aS = VEmap(i);
    //
    TopoDS_Edge E;
    TopTools_ListOfShape aLF1, aLF2;
    //
    bEdge = (aS.ShapeType() == TopAbs_EDGE);
    if (bEdge) {
      // faces connected by the edge
      E = *(TopoDS_Edge*)&aS;
      //
      const BRepOffset_ListOfInterval& L = Analyse.Type(E);
      if (L.IsEmpty()) {
        continue;
      }
      //
      BRepOffset_Type    OT   = L.First().Type();
      if (OT != BRepOffset_Convex && OT != BRepOffset_Concave) {
        continue;
      }
      //
      if (OT == BRepOffset_Concave) CurSide = TopAbs_IN;
      else                          CurSide = TopAbs_OUT;
      //-----------------------------------------------------------
      // edge is of the proper type, return adjacent faces.
      //-----------------------------------------------------------
      const TopTools_ListOfShape& Anc = Analyse.Ancestors(E);
      if (Anc.Extent() != 2) {
        continue;
      }
      //
      F1  = TopoDS::Face(Anc.First());
      F2  = TopoDS::Face(Anc.Last ());
      //
      aLF1.Append(F1);
      aLF2.Append(F2);
    }
    else {
      if (!aDMVLF1.IsBound(aS)) {
        continue;
      }
      //
      aLF1 = aDMVLF1.Find(aS);
      aLF2 = aDMVLF2.Find(aS);
      //
      CurSide = mySide;
    }
    //
    itF1.Initialize(aLF1);
    itF2.Initialize(aLF2);
    for (; itF1.More() && itF2.More(); itF1.Next(), itF2.Next()) {
      F1 = TopoDS::Face(itF1.Value());
      F2 = TopoDS::Face(itF2.Value());
      //
      OF1 = TopoDS::Face(MapSF(F1).Face());
      OF2 = TopoDS::Face(MapSF(F2).Face());
      if (!MES.IsBound(OF1)) {
        Standard_Boolean enlargeU = Standard_True;
        Standard_Boolean enlargeVfirst = Standard_True, enlargeVlast = Standard_True;
        BRepOffset_Tool::CheckBounds( F1, Analyse, enlargeU, enlargeVfirst, enlargeVlast );
        BRepOffset_Tool::EnLargeFace(OF1,NF1,Standard_True,Standard_True,enlargeU,enlargeVfirst,enlargeVlast);
        MES.Bind(OF1,NF1);
      }
      else {
        NF1 = TopoDS::Face(MES(OF1));
      }
      //
      if (!MES.IsBound(OF2)) {
        Standard_Boolean enlargeU = Standard_True;
        Standard_Boolean enlargeVfirst = Standard_True, enlargeVlast = Standard_True;
        BRepOffset_Tool::CheckBounds( F2, Analyse, enlargeU, enlargeVfirst, enlargeVlast );
        BRepOffset_Tool::EnLargeFace(OF2,NF2,Standard_True,Standard_True,enlargeU,enlargeVfirst,enlargeVlast);
        MES.Bind(OF2,NF2); 
      }
      else {
        NF2 = TopoDS::Face(MES(OF2));
      }
      //
      if (!IsDone(NF1,NF2)) {
        TopTools_ListOfShape LInt1,LInt2;
        BRepOffset_Tool::Inter3D (NF1,NF2,LInt1,LInt2,CurSide,E,bEdge);
        if (LInt1.Extent() > 1) { 
          // intersection is in seceral edges (free sewing)
          SelectEdge(aS, LInt1);
          SelectEdge(aS, LInt2);
        }
        SetDone(NF1,NF2);
        if (!LInt1.IsEmpty()) {
          Store (NF1,NF2,LInt1,LInt2);
          //
          TopoDS_Compound C;
          B.MakeCompound(C);
          //
          if (Build.IsBound(aS)) {
            const TopoDS_Shape& aSE = Build(aS);
            TopExp_Explorer aExp(aSE, TopAbs_EDGE);
            for (; aExp.More(); aExp.Next()) {
              const TopoDS_Shape& aNE = aExp.Current();
              B.Add(C, aNE);
            }
          }
          //
          it.Initialize(LInt1);
          for (; it.More(); it.Next()) {
            const TopoDS_Shape& aNE = it.Value();
            B.Add(C, aNE);
            //
            // keep connection from new edge to shape from which it was created
            TopTools_ListOfShape *pLS = &aDMIntE(aDMIntE.Add(aNE, TopTools_ListOfShape()));
            pLS->Append(aS);
            // keep connection to faces created the edge as well
            TopTools_ListOfShape* pLFF = aDMIntFF.Bound(aNE, TopTools_ListOfShape());
            pLFF->Append(F1);
            pLFF->Append(F2);
          }
          //
          Build.Bind(aS,C);
        }
        else {
          Failed.Append(aS);
        }
      } else { // IsDone(NF1,NF2)
        //  Modified by skv - Fri Dec 26 12:20:13 2003 OCC4455 Begin
        const TopTools_ListOfShape &aLInt1 = myAsDes->Descendant(NF1);
        const TopTools_ListOfShape &aLInt2 = myAsDes->Descendant(NF2);
        
        if (!aLInt1.IsEmpty()) {
          TopoDS_Compound C;
          B.MakeCompound(C);
          //
          if (Build.IsBound(aS)) {
            const TopoDS_Shape& aSE = Build(aS);
            TopExp_Explorer aExp(aSE, TopAbs_EDGE);
            for (; aExp.More(); aExp.Next()) {
              const TopoDS_Shape& aNE = aExp.Current();
              B.Add(C, aNE);
            }
          }
          //
          for (it.Initialize(aLInt1) ; it.More(); it.Next()) {
            const TopoDS_Shape &anE1 = it.Value();
            //
            for (it1.Initialize(aLInt2) ; it1.More(); it1.Next()) {
              const TopoDS_Shape &anE2 = it1.Value();
              if (anE1.IsSame(anE2)) {
                B.Add(C, anE1);
                //
                TopTools_ListOfShape *pLS = aDMIntE.ChangeSeek(anE1);
                if (pLS) {
                  pLS->Append(aS);
                }
              }
            }
          }
          Build.Bind(aS,C);
        }
        else {
          Failed.Append(aS);
        }
      }
    }
    //  Modified by skv - Fri Dec 26 12:20:14 2003 OCC4455 End
  }
  //
  // create unique intersection for each localized shared part
  aNb = aDMIntE.Extent();
  for (i = 1; i <= aNb; ++i) {
    const TopTools_ListOfShape& aLS = aDMIntE(i);
    if (aLS.Extent() < 2) {
      continue;
    }
    //
    // intersection edge
    const TopoDS_Edge& aE = TopoDS::Edge(aDMIntE.FindKey(i));
    // faces created the edge
    const TopTools_ListOfShape& aLFF = aDMIntFF.Find(aE);
    const TopoDS_Shape& aF1 = aLFF.First();
    const TopoDS_Shape& aF2 = aLFF.Last();

    // Build really localized blocks from the original shapes in <aLS>:
    // 1. Find edges from original faces connected to two or more shapes in <aLS>;
    // 2. Make connexity blocks from edges in <aLS> and found connection edges;
    // 3. Check if the vertices from <aLS> are not connected by these connection edges:
    //    a. If so - add these vertices to Connexity Block containing the corresponding
    //       connexity edge;
    //    b. If not - add this vertex to list of connexity blocks
    // 4. Create unique intersection edge for each connexity block

    // list of vertices
    TopTools_ListOfShape aLV;
    // compound of edges to build connexity blocks
    TopoDS_Compound aCE;
    B.MakeCompound(aCE);
    TopTools_MapOfShape aMS;
    TopTools_ListIteratorOfListOfShape aItLS(aLS);
    for (; aItLS.More(); aItLS.Next()) {
      const TopoDS_Shape& aS = aItLS.Value();
      aMS.Add(aS);
      if (aS.ShapeType() == TopAbs_EDGE) {
        B.Add(aCE, aS);
      }
      else {
        aLV.Append(aS);
      }
    }
    //
    // look for additional edges to connect the shared parts
    TopTools_MapOfShape aMEConnection;
    for (Standard_Integer j = 0; j < 2; ++j) {
      const TopoDS_Shape& aF = !j ? aF1 : aF2;
      //
      TopExp_Explorer aExp(aF, TopAbs_EDGE);
      for (; aExp.More(); aExp.Next()) {
        const TopoDS_Shape& aEF = aExp.Current();
        if (aMS.Contains(aEF) || aMEConnection.Contains(aEF)) {
          continue;
        }
        //
        TopoDS_Vertex aV1, aV2;
        TopExp::Vertices(TopoDS::Edge(aEF), aV1, aV2);
        //
        // find parts to which the edge is connected
        Standard_Integer iCounter = 0;
        aItLS.Initialize(aLS);
        for (; aItLS.More(); aItLS.Next()) {
          const TopoDS_Shape& aS = aItLS.Value();
          // iterator is not suitable here, because aS may be a vertex
          TopExp_Explorer aExpV(aS, TopAbs_VERTEX);
          for (; aExpV.More(); aExpV.Next()) {
            const TopoDS_Shape& aV = aExpV.Current();
            if (aV.IsSame(aV1) || aV.IsSame(aV2)) {
              ++iCounter;
              break;
            }
          }
        }
        //
        if (iCounter >= 2) {
          B.Add(aCE, aEF);
          aMEConnection.Add(aEF);
        }
      }
    }
    //
    TopTools_ListOfShape aLCBE;
    BOPTools_AlgoTools::MakeConnexityBlocks(aCE, TopAbs_VERTEX, TopAbs_EDGE, aLCBE);
    //
    // create connexity blocks for alone vertices
    TopTools_ListOfShape aLCBV;
    TopTools_ListIteratorOfListOfShape aItLV(aLV);
    for (; aItLV.More(); aItLV.Next()) {
      const TopoDS_Shape& aV = aItLV.Value();
      // check if this vertex is contained in some connexity block of edges
      TopTools_ListIteratorOfListOfShape aItLCB(aLCBE);
      for (; aItLCB.More(); aItLCB.Next()) {
        TopoDS_Shape& aCB = aItLCB.ChangeValue();
        TopExp_Explorer aExpV(aCB, TopAbs_VERTEX);
        for (; aExpV.More(); aExpV.Next()) {
          if (aV.IsSame(aExpV.Current())) {
            B.Add(aCB, aV);
            break;
          }
        }
        if (aExpV.More()) {
          break;
        }
      }
      //
      if (!aItLCB.More()) {
        TopoDS_Compound aCV;
        B.MakeCompound(aCV);
        B.Add(aCV, aV);
        aLCBV.Append(aCV);
      }
    }
    //
    aLCBE.Append(aLCBV);
    //
    if (aLCBE.Extent() == 1) {
      continue;
    }
    //
    const TopoDS_Shape& aNF1 = MES(MapSF(aF1).Face());
    const TopoDS_Shape& aNF2 = MES(MapSF(aF2).Face());
    //
    TopTools_ListIteratorOfListOfShape aItLCB(aLCBE);
    for (aItLCB.Next(); aItLCB.More(); aItLCB.Next()) {
      // make new edge with different tedge instance
      TopoDS_Edge aNewEdge;
      TopoDS_Vertex aV1, aV2;
      Standard_Real aT1, aT2;
      //
      TopExp::Vertices(aE, aV1, aV2);
      BRep_Tool::Range(aE, aT1, aT2);
      //
      BOPTools_AlgoTools::MakeSplitEdge(aE, aV1, aT1, aV2, aT2, aNewEdge);
      //
      myAsDes->Add(aNF1, aNewEdge);
      myAsDes->Add(aNF2, aNewEdge);
      //
      const TopoDS_Shape& aCB = aItLCB.Value();
      TopoDS_Iterator aItCB(aCB);
      for (; aItCB.More(); aItCB.Next()) {
        const TopoDS_Shape& aS = aItCB.Value();
        if (aMEConnection.Contains(aS)) {
          continue;
        }
        TopoDS_Shape& aCI = Build.ChangeFind(aS);
        //
        TopoDS_Compound aNewCI;
        B.MakeCompound(aNewCI);
        TopExp_Explorer aExp(aCI, TopAbs_EDGE);
        for (; aExp.More(); aExp.Next()) {
          const TopoDS_Shape& aSx = aExp.Current();
          if (!aSx.IsSame(aE)) {
            B.Add(aNewCI, aSx);
          }
        }
        B.Add(aNewCI, aNewEdge);
        aCI = aNewCI;
      }
    }
  }
}

//=======================================================================
//function : ContextIntByInt
//purpose  : 
//=======================================================================

void BRepOffset_Inter3d::ContextIntByInt
(const TopTools_IndexedMapOfShape&      ContextFaces, 
 const Standard_Boolean                 ExtentContext,
 const BRepOffset_DataMapOfShapeOffset& MapSF,
 const BRepOffset_Analyse&              Analyse,
 TopTools_DataMapOfShapeShape&          MES,
 TopTools_DataMapOfShapeShape&          Build,
 TopTools_ListOfShape&                  Failed,
 const Standard_Boolean                 bIsPlanar)
{
  TopTools_MapOfShape              MV;
  TopExp_Explorer                  exp;
  TopoDS_Face                      OF,NF,WCF;
  TopoDS_Edge                      OE;
  TopoDS_Compound                  C;
  BRep_Builder                     B;
  TopTools_ListIteratorOfListOfShape it, itF;
  Standard_Integer i, j, aNb, aNbVE;
  Standard_Boolean bEdge;

  aNb = ContextFaces.Extent();
  for (i = 1; i <= aNb; i++) {
    const TopoDS_Face& CF = TopoDS::Face(ContextFaces(i));
    myTouched.Add(CF);
    if (ExtentContext) {
      BRepOffset_Tool::EnLargeFace(CF,NF,0,0);
      MES.Bind(CF,NF);
    }
  }
  TopAbs_State Side = TopAbs_OUT;
 
  for (i = 1; i <= aNb; i++) {
    const TopoDS_Face& CF  = TopoDS::Face(ContextFaces(i));
    if (ExtentContext) WCF = TopoDS::Face(MES(CF));
    else               WCF = CF;

    TopTools_IndexedMapOfShape VEmap;
    TopExp::MapShapes(CF.Oriented(TopAbs_FORWARD), TopAbs_EDGE  , VEmap);
    //
    if (bIsPlanar) {
      TopExp::MapShapes(CF.Oriented(TopAbs_FORWARD), TopAbs_VERTEX, VEmap);
    }
    //
    aNbVE = VEmap.Extent();
    for (j = 1; j <= aNbVE; ++j) {
      const TopoDS_Shape& aS = VEmap(j);
      //
      bEdge = (aS.ShapeType() == TopAbs_EDGE);
      //
      TopoDS_Edge E;
      TopTools_ListOfShape Anc;
      //
      if (bEdge) {
        // faces connected by the edge
        //
        E = *(TopoDS_Edge*)&aS;
        if (!Analyse.HasAncestor(E)) {
          //----------------------------------------------------------------
          // the edges of faces of context that are not in the initial shape
          // can appear in the result.
          //----------------------------------------------------------------
          if (!ExtentContext) {
            myAsDes->Add(CF,E);
            myNewEdges.Add(E);
          }
          else {
            if (!MES.IsBound(E)) {
              TopoDS_Edge NE;
              Standard_Real f,l,Tol;
              BRep_Tool::Range(E,f,l);
              Tol = BRep_Tool::Tolerance(E);
              ExtentEdge(CF,E,NE);
              TopoDS_Vertex V1,V2;
              TopExp::Vertices(E,V1,V2);
              NE.Orientation(TopAbs_FORWARD);
              myAsDes->Add(NE,V1.Oriented(TopAbs_REVERSED));
              myAsDes->Add(NE,V2.Oriented(TopAbs_FORWARD));
              TopoDS_Shape aLocalShape = V1.Oriented(TopAbs_INTERNAL);
              B.UpdateVertex(TopoDS::Vertex(aLocalShape),f,NE,Tol);
              aLocalShape = V2.Oriented(TopAbs_INTERNAL);
              B.UpdateVertex(TopoDS::Vertex(aLocalShape),l,NE,Tol);
//            B.UpdateVertex(TopoDS::Vertex(V1.Oriented(TopAbs_INTERNAL)),f,NE,Tol);
//            B.UpdateVertex(TopoDS::Vertex(V2.Oriented(TopAbs_INTERNAL)),l,NE,Tol);
              NE.Orientation(E.Orientation());
              myAsDes->Add(CF,NE);
              myNewEdges.Add(NE);
              MES.Bind(E,NE);
            }
            else {
              TopoDS_Shape NE = MES(E);
              TopoDS_Shape aLocalShape = NE.Oriented(E.Orientation());
              myAsDes->Add(CF,aLocalShape);
//            myAsDes->Add(CF,NE.Oriented(E.Orientation()));
            }
          }
          continue;
        } 
        Anc = Analyse.Ancestors(E);
      }
      else {
        // faces connected by the vertex
        //
        if (!Analyse.HasAncestor(aS)) {
          continue;
        }
        //
        const TopTools_ListOfShape& aLE = Analyse.Ancestors(aS);
        it.Initialize(aLE);
        for (; it.More(); it.Next()) {
          const TopoDS_Edge& aE = *(TopoDS_Edge*)&it.Value();
          //
          if (BRep_Tool::Degenerated(aE)) {
            continue;
          }
          //
          if (VEmap.Contains(aE)) {
            continue;
          }
          //
          const TopTools_ListOfShape& aLF = Analyse.Ancestors(aE);
          itF.Initialize(aLF);
          for (; itF.More(); itF.Next()) {
            const TopoDS_Shape& aF = itF.Value();
            Standard_Boolean bAdd = Standard_True;
            exp.Init(aF, TopAbs_EDGE);
            for (; exp.More() && bAdd; exp.Next()) {
              const TopoDS_Shape& aEF = exp.Current();
              bAdd = !VEmap.Contains(aEF);
            }
            if (bAdd) {
              Anc.Append(aF);
            }
          }
        }
      }
      //
      itF.Initialize(Anc);
      for (; itF.More(); itF.Next()) {
        const TopoDS_Face& F = TopoDS::Face(itF.Value());
        OF = TopoDS::Face(MapSF(F).Face());
        TopoDS_Shape aLocalShape = MapSF(F).Generated(E);
        OE = TopoDS::Edge(aLocalShape);
//      OE = TopoDS::Edge(MapSF(F).Generated(E));
        if (!MES.IsBound(OF)) {
          BRepOffset_Tool::EnLargeFace(OF,NF,1,1);
          MES.Bind(OF,NF);
        }
        else {
          NF = TopoDS::Face(MES(OF));
        }
        if (!IsDone(NF,CF)) {
          TopTools_ListOfShape LInt1,LInt2;
          TopTools_ListOfShape LOE;
          LOE.Append(OE);
          BRepOffset_Tool::Inter3D (WCF,NF,LInt1,LInt2,Side,E,bEdge);
          SetDone(NF,CF);
          if (!LInt1.IsEmpty()) {
            Store (CF,NF,LInt1,LInt2);
            if ((LInt1.Extent() == 1) && !Build.IsBound(aS)) {
              Build.Bind(aS,LInt1.First());
            }
            else {
              B.MakeCompound(C);
              if (Build.IsBound(aS)) {
                const TopoDS_Shape& aSE = Build(aS);
                exp.Init(aSE, TopAbs_EDGE);
                for (; exp.More(); exp.Next()) {
                  const TopoDS_Shape& aNE = exp.Current();
                  B.Add(C, aNE);
                }
              }
              //
              for (it.Initialize(LInt1) ; it.More(); it.Next()) {
                B.Add(C,it.Value());
              }
              Build.Bind(aS,C);
            }
          }
          else {
            Failed.Append(aS);
          }
        }
      }
    }
  }
}

//=======================================================================
//function : ContextIntByArc
//purpose  : 
//=======================================================================

void BRepOffset_Inter3d::ContextIntByArc(const TopTools_IndexedMapOfShape& ContextFaces, 
                                         const Standard_Boolean            InSide,
                                         const BRepOffset_Analyse&         Analyse, 
                                         const BRepAlgo_Image&             InitOffsetFace, 
                                               BRepAlgo_Image&             InitOffsetEdge)

{ 
  TopTools_ListOfShape                      LInt1,LInt2;
  TopTools_MapOfShape                       MV;
  TopExp_Explorer                           exp;
  TopoDS_Face                               OF1,OF2;
  TopoDS_Edge                               OE;
  BRep_Builder                              B;  
  TopoDS_Edge                               NullEdge;
  Standard_Integer j;

  for (j = 1; j <= ContextFaces.Extent(); j++) {
    const TopoDS_Face& CF = TopoDS::Face(ContextFaces(j));
    myTouched.Add(CF);
  }

  for (j = 1; j <= ContextFaces.Extent(); j++) {
    const TopoDS_Face& CF = TopoDS::Face(ContextFaces(j));
    for (exp.Init(CF.Oriented(TopAbs_FORWARD),TopAbs_EDGE); 
         exp.More(); exp.Next()) {
      const TopoDS_Edge& E = TopoDS::Edge(exp.Current());
      if (!Analyse.HasAncestor(E)) {
        if (InSide)
          myAsDes->Add(CF,E);
        else {
          TopoDS_Edge NE;
          if (!InitOffsetEdge.HasImage(E)) {
            Standard_Real f,l,Tol;
            BRep_Tool::Range(E,f,l);
            Tol = BRep_Tool::Tolerance(E);
            ExtentEdge(CF,E,NE);
            TopoDS_Vertex V1,V2;
            TopExp::Vertices(E,V1,V2);
            NE.Orientation(TopAbs_FORWARD);
            myAsDes->Add(NE,V1.Oriented(TopAbs_REVERSED));
            myAsDes->Add(NE,V2.Oriented(TopAbs_FORWARD));
            TopoDS_Shape aLocalShape = V1.Oriented(TopAbs_INTERNAL);
            B.UpdateVertex(TopoDS::Vertex(aLocalShape),f,NE,Tol);
            aLocalShape = V2.Oriented(TopAbs_INTERNAL);
            B.UpdateVertex(TopoDS::Vertex(aLocalShape),l,NE,Tol);
//            B.UpdateVertex(TopoDS::Vertex(V1.Oriented(TopAbs_INTERNAL)),f,NE,Tol);
//            B.UpdateVertex(TopoDS::Vertex(V2.Oriented(TopAbs_INTERNAL)),l,NE,Tol);
            NE.Orientation(E.Orientation());
            myAsDes->Add(CF,NE);
            InitOffsetEdge.Bind(E,NE);
          }
          else {
            NE = TopoDS::Edge(InitOffsetEdge.Image(E).First());
            myAsDes->Add(CF,NE.Oriented(E.Orientation()));
          }
        }
        continue;
      }
      OE.Nullify();
      //---------------------------------------------------
      // OF1 parallel facee generated by the ancestor of E.
      //---------------------------------------------------
      const TopoDS_Shape SI = Analyse.Ancestors(E).First();
      OF1 = TopoDS::Face(InitOffsetFace.Image(SI).First());
      OE  = TopoDS::Edge(InitOffsetEdge.Image(E).First());     

      {
        //Check if OE has pcurve in CF

        Standard_Real   f,l;

        Handle (Geom2d_Curve) C1 = BRep_Tool::CurveOnSurface(OE,CF,f,l);
        Handle (Geom2d_Curve) C2 = BRep_Tool::CurveOnSurface(OE,OF1,f,l); 

        if(C1.IsNull() || C2.IsNull())
        {
          continue;
        }
      }

      //--------------------------------------------------
      // MAJ of OE on cap CF.
      //--------------------------------------------------
//      TopTools_ListOfShape LOE; LOE.Append(OE);              
//      BRepOffset_Tool::TryProject(CF,OF1,LOE,LInt1,LInt2,mySide);
//      LInt2.Clear();
//      StoreInter3d(CF,OF1,myTouched,NewEdges,InterDone,myAsDes,
//                   LInt1,LInt2);
      LInt1.Clear(); LInt1.Append(OE);
      LInt2.Clear();    
      TopAbs_Orientation anOri1, anOri2;
      BRepOffset_Tool::OrientSection(OE,CF,OF1, anOri1,anOri2);
//    if (mySide == TopAbs_OUT);
      anOri1 = TopAbs::Reverse(anOri1);
      LInt1.First().Orientation(anOri1);
      Store(CF,OF1,LInt1,LInt2);
      
      //------------------------------------------------------
      // Processing of offsets on the ancestors of vertices.
      //------------------------------------------------------
      TopoDS_Vertex V[2];
      TopExp::Vertices (E,V[0],V[1]);
      for (Standard_Integer i = 0; i < 2; i++) {
        if (!MV.Add(V[i])) continue;
        OF1.Nullify(); 
        const TopTools_ListOfShape& LE =  Analyse.Ancestors(V[i]);
        TopTools_ListIteratorOfListOfShape itLE(LE);
        for ( ; itLE.More(); itLE.Next()) {
          const TopoDS_Edge& EV = TopoDS::Edge(itLE.Value());
          if (InitOffsetFace.HasImage(EV)) {
            //-------------------------------------------------
            // OF1 parallel face generated by an ancester edge of V[i].
            //-------------------------------------------------
            OF1 = TopoDS::Face(InitOffsetFace.Image(EV).First());
            OE  = TopoDS::Edge(InitOffsetEdge.Image(V[i]).First());

      {
        //Check if OE has pcurve in CF and OF1

        Standard_Real   f,l;

        Handle (Geom2d_Curve) C1 = BRep_Tool::CurveOnSurface(OE,CF,f,l);
        Handle (Geom2d_Curve) C2 = BRep_Tool::CurveOnSurface(OE,OF1,f,l); 

        if(C1.IsNull() || C2.IsNull())
        {
          continue;
        }
      }

            //--------------------------------------------------
            // MAj of OE on cap CF.
            //--------------------------------------------------
            //              LOE.Clear(); LOE.Append(OE);
            //              BRepOffset_Tool::TryProject(CF,OF1,LOE,LInt1,LInt2,mySide);
            //              LInt2.Clear();
            //              StoreInter3d(CF,OF1,myTouched,NewEdges,InterDone,myAsDes,
            //                           LInt1,LInt2);
            LInt1.Clear(); LInt1.Append(OE);
            LInt2.Clear();    
            TopAbs_Orientation O1,O2;
            BRepOffset_Tool::OrientSection(OE,CF,OF1,O1,O2);      
//            if (mySide == TopAbs_OUT);
            O1 = TopAbs::Reverse(O1);
            LInt1.First().Orientation(O1);
            Store(CF,OF1,LInt1,LInt2);
          }
        }
      }
    }
    
    for (exp.Init(CF.Oriented(TopAbs_FORWARD),TopAbs_VERTEX); 
         exp.More(); exp.Next()) {
      const TopoDS_Vertex&        V  = TopoDS::Vertex(exp.Current());
      if (!Analyse.HasAncestor(V)) {
        continue;
      }
      const TopTools_ListOfShape& LE =  Analyse.Ancestors(V);
      TopTools_ListIteratorOfListOfShape itLE(LE);
      for (; itLE.More(); itLE.Next()) {
        const TopoDS_Edge& EV = TopoDS::Edge(itLE.Value());
        const TopTools_ListOfShape& LF = Analyse.Ancestors(EV);
        TopTools_ListIteratorOfListOfShape itLF(LF);
        for ( ; itLF.More(); itLF.Next()) {
          const TopoDS_Face& FEV = TopoDS::Face(itLF.Value());
          //-------------------------------------------------
          // OF1 parallel face generated by uneFace ancestor of V[i].
          //-------------------------------------------------
          OF1 = TopoDS::Face(InitOffsetFace.Image(FEV).First());
          if (!IsDone(OF1,CF)) {
            //-------------------------------------------------------
            // Find if one of edges of OF1 has no trace in CF.
            //-------------------------------------------------------
            TopTools_ListOfShape LOE;
            TopExp_Explorer exp2(OF1.Oriented(TopAbs_FORWARD),TopAbs_EDGE);
            for ( ;exp2.More(); exp2.Next()) {
              LOE.Append(exp2.Current());
            }
            BRepOffset_Tool::TryProject(CF,OF1,LOE,LInt1,LInt2,mySide,myTol);
            //-------------------------------------------------------
            // If no trace try intersection.
            //-------------------------------------------------------
            if (LInt1.IsEmpty()) {
              BRepOffset_Tool::Inter3D (CF,OF1,LInt1,LInt2,mySide,NullEdge);
            }
            Store (CF,OF1,LInt1,LInt2);
          }
        }
      }
    } 
  }
}

//=======================================================================
//function : AddCommonEdges
//purpose  : 
//=======================================================================

void BRepOffset_Inter3d::AddCommonEdges(const TopTools_ListOfShape&)
{
}


//=======================================================================
//function : SetDone
//purpose  : 
//=======================================================================

void BRepOffset_Inter3d::SetDone(const TopoDS_Face& F1, 
                                 const TopoDS_Face& F2)
{
  if (!myDone.IsBound(F1)) {
    TopTools_ListOfShape empty;
    myDone.Bind(F1,empty);
  }
  myDone(F1).Append(F2);
  if (!myDone.IsBound(F2)) {
    TopTools_ListOfShape empty;
    myDone.Bind(F2,empty);
  }
  myDone(F2).Append(F1);
}


//=======================================================================
//function : IsDone
//purpose  : 
//=======================================================================

Standard_Boolean BRepOffset_Inter3d::IsDone(const TopoDS_Face& F1, 
                                            const TopoDS_Face& F2) 
const 
{
  if (myDone.IsBound(F1)) {
    TopTools_ListIteratorOfListOfShape it (myDone(F1));
    for (; it.More(); it.Next()) {
      if (it.Value().IsSame(F2)) return Standard_True;
    }
  }
  return Standard_False;
}


//=======================================================================
//function : TouchedFaces
//purpose  : 
//=======================================================================

TopTools_IndexedMapOfShape& BRepOffset_Inter3d::TouchedFaces()
{
  return myTouched;
}


//=======================================================================
//function : AsDes
//purpose  : 
//=======================================================================

Handle(BRepAlgo_AsDes) BRepOffset_Inter3d::AsDes() const 
{
  return myAsDes;
}


//=======================================================================
//function : NewEdges
//purpose  : 
//=======================================================================

TopTools_IndexedMapOfShape& BRepOffset_Inter3d::NewEdges() 
{
  return myNewEdges;
}


//=======================================================================
//function : Store
//purpose  : 
//=======================================================================

void BRepOffset_Inter3d::Store(const TopoDS_Face& F1, 
                               const TopoDS_Face& F2, 
                               const TopTools_ListOfShape& LInt1, 
                               const TopTools_ListOfShape& LInt2)
{
  if (!LInt1.IsEmpty()) {
    myTouched.Add(F1);
    myTouched.Add(F2);
    myAsDes->Add( F1,LInt1);
    myAsDes->Add( F2,LInt2);
    TopTools_ListIteratorOfListOfShape it(LInt1);
    for (; it.More(); it.Next()) {
      myNewEdges.Add(it.Value());
    }
  }
  SetDone(F1,F2);
}