src/GeomAlgoAPI/GeomAlgoAPI_SketchBuilder.cpp

   1 // File:        GeomAlgoAPI_SketchBuilder.cpp
   2 // Created:     02 Jun 2014
   3 // Author:      Artem ZHIDKOV
   4
   5 #include <GeomAlgoAPI_SketchBuilder.h>
   6
   7 #include <set>
   8
   9 #include <gp_Dir.hxx>
  10 #include <gp_Pln.hxx>
  11
  12 #include <BOPAlgo_Builder.hxx>
  13 #include <BOPAlgo_Operation.hxx>
  14 #include <BOPAlgo_PaveFiller.hxx>
  15 #include <BOPTools.hxx>
  16 #include <BRep_Builder.hxx>
  17 #include <BRep_Curve3D.hxx>
  18 #include <BRep_TEdge.hxx>
  19 #include <BRep_TVertex.hxx>
  20 #include <BRepAlgoAPI_Cut.hxx>
  21 #include <BRepBuilderAPI_MakeFace.hxx>
  22 #include <BRepClass_FaceClassifier.hxx>
  23 #include <Geom_Curve.hxx>
  24 #include <Geom_Plane.hxx>
  25 #include <TopExp.hxx>
  26 #include <TopExp_Explorer.hxx>
  27 #include <TopoDS_Edge.hxx>
  28 #include <TopoDS_Face.hxx>
  29 #include <TopoDS_Vertex.hxx>
  30 #include <TopoDS_Wire.hxx>
  31
  32 #include <Precision.hxx>
  33
  34 #ifndef DBL_MAX
  35 #define DBL_MAX 1.7976931348623158e+308
  36 #endif
  37
  38
  39 const double tolerance = Precision::Confusion();
  40 // This value helps to find direction on the boundaries of curve.
  41 // It is not significant for lines, but is used for circles to avoid
  42 // wrong directions of movement (when two edges are tangent on the certain vertex)
  43 const double shift     = acos(1.0 - 2.0 * tolerance);
  44
  45 /// \brief Search first vertex - the vertex with lowest x coordinate, which is used in 2 edges at least
  46 static const TopoDS_Shape& findStartVertex(
  47           const BOPCol_IndexedDataMapOfShapeListOfShape& theMapVE,
  48           const gp_Dir& theDirX, const gp_Dir& theDirY);
  49
  50 /// \brief Search the vertex on the sketch candidate to be the next one in the loop
  51 static void findNextVertex(
  52           const TopoDS_Shape&                            theStartVertex,
  53           const BOPCol_IndexedDataMapOfShapeListOfShape& theVertexEdgeMap,
  54           const gp_Dir&                                  theStartDir,
  55           const gp_Dir&                                  theNormal,
  56                 TopoDS_Shape&                            theNextVertex,
  57                 TopoDS_Shape&                            theNextEdge,
  58                 gp_Dir&                                  theNextDir);
  59
  60 /// \brief Create planar face using the edges surrounding it
  61 static void createFace(const TopoDS_Shape&                      theStartVertex,
  62                        const std::list<TopoDS_Shape>::iterator& theStartEdge,
  63                        const std::list<TopoDS_Shape>::iterator& theEndOfEdges,
  64                        const gp_Pln&                            thePlane,
  65                              TopoDS_Face&                       theResFace);
  66
  67 /// \bief Create planar wire
  68 static void createWireList(const TopoDS_Shape&                      theStartVertex,
  69                            const std::list<TopoDS_Shape>::iterator& theStartEdge,
  70                            const std::list<TopoDS_Shape>::iterator& theEndOfEdges,
  71                            const std::set<Handle(TopoDS_TShape)>&   theEdgesInLoops,
  72                                  std::list<TopoDS_Wire>&            theResWires);
  73
  74 /// \brief Calculate outer tengency on the edge in specified vertex
  75 static gp_Dir getOuterEdgeDirection(const TopoDS_Shape& theEdge,
  76                                     const TopoDS_Shape& theVertex);
  77
  78 /// \brief Unnecessary edges will be removed from the map.
  79 ///        Positions of iterator will be updated
  80 static void removeWasteEdges(
  81                 std::list<TopoDS_Shape>::iterator&  theStartVertex,
  82                 std::list<TopoDS_Shape>::iterator&  theStartEdge,
  83           const std::list<TopoDS_Shape>::iterator&  theEndOfVertexes,
  84           const std::list<TopoDS_Shape>::iterator&  theEndOfEdges,
  85           BOPCol_IndexedDataMapOfShapeListOfShape&  theMapVE);
  86
  87
  88
  89
  90 void GeomAlgoAPI_SketchBuilder::createFaces(
  91           const boost::shared_ptr<GeomAPI_Pnt>&                theOrigin,
  92           const boost::shared_ptr<GeomAPI_Dir>&                theDirX,
  93           const boost::shared_ptr<GeomAPI_Dir>&                theDirY,
  94           const boost::shared_ptr<GeomAPI_Dir>&                theNorm,
  95           const std::list< boost::shared_ptr<GeomAPI_Shape> >& theFeatures,
  96                 std::list< boost::shared_ptr<GeomAPI_Shape> >& theResultFaces,
  97                 std::list< boost::shared_ptr<GeomAPI_Shape> >& theResultWires)
  98 {
  99   if (theFeatures.empty())
 100     return ;
 101
 102   // Create the list of edges with shared vertexes
 103   BOPAlgo_Builder aBuilder;
 104   BOPAlgo_PaveFiller aPF;
 105   TopoDS_Shape aFeaturesCompound;
 106
 107   if (theFeatures.size() == 1)
 108   { // If there is only one feature, BOPAlgo_Builder will decline to work. Need to process it anyway
 109     aFeaturesCompound = theFeatures.front()->impl<TopoDS_Shape>();
 110   }
 111   else
 112   {
 113     std::list< boost::shared_ptr<GeomAPI_Shape> >::const_iterator anIt = theFeatures.begin();
 114     for (; anIt != theFeatures.end(); anIt++)
 115     {
 116       boost::shared_ptr<GeomAPI_Shape> aPreview(*anIt);
 117       aBuilder.AddArgument(aPreview->impl<TopoDS_Edge>());
 118     }
 119     aPF.SetArguments(aBuilder.Arguments());
 120     aPF.Perform();
 121     int aErr = aPF.ErrorStatus();
 122     if (aErr) return ;
 123     aBuilder.PerformWithFiller(aPF);
 124     aErr = aBuilder.ErrorStatus();
 125     if (aErr) return ;
 126     aFeaturesCompound = aBuilder.Shape();
 127   }
 128
 129   BOPCol_IndexedDataMapOfShapeListOfShape aMapVE; // map between vertexes and edges
 130   BOPTools::MapShapesAndAncestors(aFeaturesCompound, TopAbs_VERTEX, TopAbs_EDGE, aMapVE);
 131
 132   gp_Dir aDirX = theDirX->impl<gp_Dir>();
 133   gp_Dir aDirY = theDirY->impl<gp_Dir>();
 134   gp_Dir aNorm = theNorm->impl<gp_Dir>();
 135
 136   gp_Pln aPlane(theOrigin->impl<gp_Pnt>(), aNorm);
 137
 138   // Set of edges used in loops
 139   std::set<Handle(TopoDS_TShape)> anEdgesInLoops;
 140   // Lists for processed vertexes and edges
 141   std::list<TopoDS_Shape> aProcVertexes;
 142   std::list<TopoDS_Shape> aProcEdges;
 143
 144   // Search the start vertex
 145   TopoDS_Shape aStartVertex = findStartVertex(aMapVE, aDirX, aDirY);
 146   aProcVertexes.push_back(aStartVertex);
 147
 148   TopoDS_Shape aCurVertex = aStartVertex;
 149   gp_Dir aCurDir = aDirY.Reversed();
 150   gp_Dir aCurNorm = aNorm.Reversed();
 151
 152   // Go through the edges and find loops
 153   TopoDS_Shape aNextVertex;
 154   TopoDS_Shape aBindingEdge;
 155   gp_Dir aNextDir;
 156   while (aMapVE.Extent() > 0)
 157   {
 158     findNextVertex(aCurVertex, aMapVE, aCurDir, aCurNorm, aNextVertex, aBindingEdge, aNextDir);
 159     aCurNorm = aNorm;
 160
 161     // Try to find next vertex in the list of already processed
 162     std::list<TopoDS_Shape>::iterator          aVertIter = aProcVertexes.begin();
 163     std::list<TopoDS_Shape>::iterator          anEdgeIter = aProcEdges.begin();
 164     for ( ; aVertIter != aProcVertexes.end(); aVertIter++)
 165     {
 166       if (aVertIter->TShape() == aNextVertex.TShape())
 167         break;
 168       if (anEdgeIter != aProcEdges.end())
 169         anEdgeIter++;
 170     }
 171
 172     aProcVertexes.push_back(aNextVertex);
 173     aProcEdges.push_back(aBindingEdge);
 174
 175     // The loop was found
 176     if (aVertIter != aProcVertexes.end())
 177     {
 178       // If the binding edge is a full circle, then the list may be empty before addition. Need to update edge iterator
 179       if (aProcEdges.size() == 1)
 180         anEdgeIter = aProcEdges.begin();
 181
 182       if (aVertIter != aProcVertexes.begin())
 183       {
 184         // Check the orientation of the loop
 185         gp_Dir aCN = getOuterEdgeDirection(*anEdgeIter, *aVertIter);
 186         gp_Dir aCP = getOuterEdgeDirection(aProcEdges.back(), *aVertIter);
 187         aCN.Reverse();
 188         aCP.Reverse();
 189         if (aCN.DotCross(aCP, aNorm) < -tolerance)
 190         {
 191           // The found loop has wrong orientation and may contain sub-loops.
 192           // Need to check it onle again with another initial direction.
 193           aCurVertex = *aVertIter;
 194           do {
 195             aProcVertexes.pop_back();
 196             aProcEdges.pop_back();
 197           } while (aCurVertex != aProcVertexes.back());
 198           aCurDir = getOuterEdgeDirection(aProcEdges.back(), aCurVertex);
 199           aCurNorm = aNorm.Reversed();
 200           continue;
 201         }
 202       }
 203
 204       // When the orientation is correct or the edges looped through
 205       // the first element, create new face and remove unnecessary edges.
 206       TopoDS_Face aPatch;
 207       createFace(*aVertIter, anEdgeIter, aProcEdges.end(), aPlane, aPatch);
 208       if (!aPatch.IsNull())
 209       {
 210         boost::shared_ptr<GeomAPI_Shape> aFace(new GeomAPI_Shape);
 211         aFace->setImpl(new TopoDS_Shape(aPatch));
 212         theResultFaces.push_back(aFace);
 213       }
 214       // push the edges used in the loop to the map
 215       std::list<TopoDS_Shape>::iterator anIter;
 216       for (anIter = anEdgeIter; anIter != aProcEdges.end(); anIter++)
 217         anEdgesInLoops.insert(anIter->TShape());
 218       // remove unnecessary edges
 219       std::list<TopoDS_Shape>::iterator aCopyVLoop = aVertIter;
 220       std::list<TopoDS_Shape>::iterator aCopyELoop = anEdgeIter;
 221       removeWasteEdges(aVertIter, anEdgeIter, aProcVertexes.end(), aProcEdges.end(), aMapVE);
 222
 223       // revert the list of remaining edges
 224       std::list<TopoDS_Shape> aRemainVertexes;
 225       for ( ; aVertIter != aProcVertexes.end(); aVertIter++)
 226         aRemainVertexes.push_front(*aVertIter);
 227       std::list<TopoDS_Shape> aRemainEdges;
 228       for ( ; anEdgeIter != aProcEdges.end(); anEdgeIter++)
 229         aRemainEdges.push_front(*anEdgeIter);
 230       // remove edges and vertexes used in the loop and add remaining ones
 231       aProcVertexes.erase(aCopyVLoop, aProcVertexes.end());
 232       aProcVertexes.insert(aProcVertexes.end(), aRemainVertexes.begin(), aRemainVertexes.end());
 233       aProcEdges.erase(aCopyELoop, aProcEdges.end());
 234       aProcEdges.insert(aProcEdges.end(), aRemainEdges.begin(), aRemainEdges.end());
 235
 236       // Recalculate current vertex and current direction
 237       if (!aProcVertexes.empty())
 238       {
 239         aNextVertex = aProcVertexes.back();
 240         if (!aProcEdges.empty())
 241           aNextDir = getOuterEdgeDirection(aProcEdges.back(), aNextVertex);
 242         else aNextDir = aDirY;
 243       }
 244     }
 245
 246     // if next vertex connected only to alone edge, this is a part of wire (not a closed loop),
 247     // we need to go back through the list of already checked edges to find a branching vertex
 248     if (!aMapVE.IsEmpty() && aMapVE.Contains(aNextVertex) &&
 249         aMapVE.FindFromKey(aNextVertex).Size() == 1)
 250     {
 251       std::list<TopoDS_Shape>::reverse_iterator aVRIter = aProcVertexes.rbegin();
 252       std::list<TopoDS_Shape>::reverse_iterator aERIter = aProcEdges.rbegin();
 253       for (++aERIter, ++aVRIter; aERIter != aProcEdges.rend(); aERIter++, aVRIter++)
 254         if (aMapVE.FindFromKey(*aVRIter).Size() > 2)
 255           break;
 256       if (aERIter != aProcEdges.rend() || aMapVE.FindFromKey(*aVRIter).Size() == 1)
 257       { // the branching vertex was found or current list of edges is a wire without branches
 258         std::list<TopoDS_Shape>::iterator aEIter;
 259         TopoDS_Shape aCurEdge;
 260         if (aERIter != aProcEdges.rend())
 261         {
 262           aEIter = aERIter.base();
 263           aCurEdge = *aERIter;
 264         }
 265         else
 266           aEIter = aProcEdges.begin();
 267         std::list<TopoDS_Wire> aTail;
 268         createWireList(*aVRIter, aEIter, aProcEdges.end(), anEdgesInLoops, aTail);
 269         std::list<TopoDS_Wire>::const_iterator aTailIter = aTail.begin();
 270         for ( ; aTailIter != aTail.end(); aTailIter++)
 271           if (!aTailIter->IsNull())
 272           {
 273             boost::shared_ptr<GeomAPI_Shape> aWire(new GeomAPI_Shape);
 274             aWire->setImpl(new TopoDS_Shape(*aTailIter));
 275             theResultWires.push_back(aWire);
 276           }
 277         std::list<TopoDS_Shape>::iterator aVIter = aVRIter.base();
 278         std::list<TopoDS_Shape>::iterator aEItCopy = aEIter;
 279         removeWasteEdges(--aVIter, aEItCopy, aProcVertexes.end(), aProcEdges.end(), aMapVE);
 280
 281         aProcEdges.erase(aEIter, aProcEdges.end());
 282         aVIter = aVRIter.base();
 283         aProcVertexes.erase(aVIter, aProcVertexes.end());
 284
 285         if (!aProcVertexes.empty())
 286         {
 287           aNextVertex = aProcVertexes.back();
 288           if (!aCurEdge.IsNull())
 289             aNextDir = getOuterEdgeDirection(aCurEdge, aNextVertex);
 290         }
 291       }
 292       else
 293       { // there is no branching vertex in the list of proceeded,
 294         // so we should revert the list and go the opposite way
 295         aProcVertexes.reverse();
 296         aProcEdges.reverse();
 297         aNextVertex = aProcVertexes.back();
 298         aNextDir = getOuterEdgeDirection(aProcEdges.back(), aNextVertex);
 299       }
 300     }
 301
 302     // When all edges of current component of connectivity are processed,
 303     // we should repeat procedure for finding initial vertex in the remaining
 304     if (!aMapVE.IsEmpty() && !aMapVE.Contains(aNextVertex))
 305     {
 306       aProcVertexes.clear();
 307       aProcEdges.clear();
 308
 309       TopoDS_Shape aStartEdge;
 310       aStartVertex = findStartVertex(aMapVE, aDirX, aDirY);
 311       aProcVertexes.push_back(aStartVertex);
 312       aNextVertex = aStartVertex;
 313       aNextDir = aDirY.Reversed();
 314       aCurNorm = aNorm.Reversed();
 315     }
 316
 317     aCurVertex = aNextVertex;
 318     aCurDir = aNextDir;
 319   }
 320
 321   if (theResultFaces.size() > 1)
 322     fixIntersections(theResultFaces);
 323 }
 324
 325 void GeomAlgoAPI_SketchBuilder::fixIntersections(
 326           std::list< boost::shared_ptr<GeomAPI_Shape> >& theFaces)
 327 {
 328   BRepClass_FaceClassifier aClassifier;
 329
 330   std::list< boost::shared_ptr<GeomAPI_Shape> >::iterator anIter1 = theFaces.begin();
 331   std::list< boost::shared_ptr<GeomAPI_Shape> >::iterator anIter2;
 332   for ( ; anIter1 != theFaces.end(); anIter1++)
 333   {
 334     anIter2 = anIter1;
 335     for (++anIter2; anIter2 != theFaces.end(); anIter2++)
 336     {
 337       const TopoDS_Face& aF1 = (*anIter1)->impl<TopoDS_Face>();
 338       TopExp_Explorer aVert2((*anIter2)->impl<TopoDS_Shape>(), TopAbs_VERTEX);
 339       for ( ; aVert2.More(); aVert2.Next())
 340       {
 341         Handle(BRep_TVertex) aV = Handle(BRep_TVertex)::DownCast(aVert2.Current().TShape());
 342         aClassifier.Perform(aF1, aV->Pnt(), tolerance);
 343         if (aClassifier.State() != TopAbs_IN)
 344           break;
 345       }
 346       if (aVert2.More())
 347       { // second shape is not inside first, change the shapes order and repeat comparision
 348         const TopoDS_Face& aF2 = (*anIter2)->impl<TopoDS_Face>();
 349         TopExp_Explorer aVert1((*anIter1)->impl<TopoDS_Shape>(), TopAbs_VERTEX);
 350         for ( ; aVert1.More(); aVert1.Next())
 351         {
 352           Handle(BRep_TVertex) aV = Handle(BRep_TVertex)::DownCast(aVert1.Current().TShape());
 353           aClassifier.Perform(aF2, aV->Pnt(), tolerance);
 354           if (aClassifier.State() != TopAbs_IN)
 355             break;
 356         }
 357         if (!aVert1.More())
 358         { // first shape should be cut from the second
 359           BRepAlgoAPI_Cut aCut((*anIter2)->impl<TopoDS_Shape>(),
 360                                (*anIter1)->impl<TopoDS_Shape>());
 361           (*anIter2)->setImpl(new TopoDS_Shape(aCut.Shape()));
 362         }
 363       }
 364       else
 365       { // second shape should be cut from the first
 366         BRepAlgoAPI_Cut aCut((*anIter1)->impl<TopoDS_Shape>(),
 367                              (*anIter2)->impl<TopoDS_Shape>());
 368         (*anIter1)->setImpl(new TopoDS_Shape(aCut.Shape()));
 369       }
 370     }
 371   }
 372 }
 373
 374
 375 // =================== Auxiliary functions ====================================
 376 const TopoDS_Shape& findStartVertex(
 377           const BOPCol_IndexedDataMapOfShapeListOfShape& theMapVE,
 378           const gp_Dir& theDirX, const gp_Dir& theDirY)
 379 {
 380   int aStartVertexInd = 1;
 381   double aMaxX = -DBL_MAX;
 382   double aMaxY = -DBL_MAX;
 383   int aNbVert = theMapVE.Extent();
 384   for (int i = 1; i <= aNbVert; i++)
 385   {
 386     const TopoDS_Vertex& aV = (const TopoDS_Vertex&)theMapVE.FindKey(i);
 387     const Handle(BRep_TVertex)& aVert = (const Handle(BRep_TVertex)&)aV.TShape();
 388     const gp_Pnt& aVertPnt = aVert->Pnt();
 389
 390     double aX = aVertPnt.XYZ().Dot(theDirX.XYZ());
 391     double aY = aVertPnt.XYZ().Dot(theDirY.XYZ());
 392     if ((aX > aMaxX || (fabs(aX - aMaxX) < tolerance && aY > aMaxY)) &&
 393         theMapVE.FindFromIndex(i).Extent() > 1)
 394     {
 395       aMaxX = aX;
 396       aMaxY = aY;
 397       aStartVertexInd = i;
 398     }
 399   }
 400   return theMapVE.FindKey(aStartVertexInd);
 401 }
 402
 403 void findNextVertex(
 404           const TopoDS_Shape&                            theStartVertex,
 405           const BOPCol_IndexedDataMapOfShapeListOfShape& theVertexEdgeMap,
 406           const gp_Dir&                                  theStartDir,
 407           const gp_Dir&                                  theNormal,
 408                 TopoDS_Shape&                            theNextVertex,
 409                 TopoDS_Shape&                            theNextEdge,
 410                 gp_Dir&                                  theNextDir)
 411 {
 412   const BOPCol_ListOfShape& anEdgesList = theVertexEdgeMap.FindFromKey(theStartVertex);
 413   BOPCol_ListOfShape::Iterator aEdIter(anEdgesList);
 414   double aBestEdgeProj = DBL_MAX;
 415   for ( ; aEdIter.More(); aEdIter.Next())
 416   {
 417     gp_Dir aTang = getOuterEdgeDirection(aEdIter.Value(), theStartVertex);
 418     aTang.Reverse();
 419
 420     // The projection is normalized in segment (-1, 1),
 421     // where (-1, 0] corresponds to the angles (pi/2, 0] between theStartDir and aTang
 422     // and [0, 1) corresponds to the angles [0, -pi/2)
 423     double aProj = (aTang.Dot(theStartDir) - 1.0) * 0.5;
 424     if (fabs(fabs(aProj) - 1) < tolerance)
 425       continue;
 426     if (theStartDir.DotCross(aTang, theNormal) < tolerance)
 427       aProj *= -1.0;
 428
 429     if (aProj < aBestEdgeProj)
 430     {
 431       aBestEdgeProj = aProj;
 432       theNextEdge = aEdIter.Value();
 433       TopExp_Explorer aVertExp(theNextEdge, TopAbs_VERTEX);
 434       for ( ; aVertExp.More(); aVertExp.Next())
 435         if (aVertExp.Current().TShape() != theStartVertex.TShape())
 436         {
 437           theNextVertex = aVertExp.Current();
 438           theNextDir = getOuterEdgeDirection(aEdIter.Value(), theNextVertex);
 439           break;
 440         }
 441       if (!aVertExp.More())
 442       { // This edge is a full circle
 443         TopoDS_Vertex aV1, aV2;
 444         TopExp::Vertices(*(const TopoDS_Edge*)(&theNextEdge), aV1, aV2);
 445         if (aV1.Orientation() == theStartVertex.Orientation())
 446           theNextVertex = aV2;
 447         else
 448           theNextVertex = aV1;
 449         theNextDir = getOuterEdgeDirection(aEdIter.Value(), theNextVertex);
 450       }
 451     }
 452   }
 453 }
 454
 455 static void addEdgeToWire(const TopoDS_Edge&  theEdge,
 456                           const BRep_Builder& theBuilder,
 457                                 TopoDS_Shape& theSpliceVertex,
 458                                 TopoDS_Wire&  theWire)
 459 {
 460   TopoDS_Edge anEdge = theEdge;
 461   bool isCurVertChanged = false;
 462   TopoDS_Shape aCurVertChanged;
 463
 464   TopExp_Explorer aVertExp(theEdge, TopAbs_VERTEX);
 465   for ( ; aVertExp.More(); aVertExp.Next())
 466   {
 467     const TopoDS_Shape& aVertex = aVertExp.Current();
 468     if (aVertex.TShape() == theSpliceVertex.TShape() &&
 469         aVertex.Orientation() != theEdge.Orientation())
 470     { // Current vertex is the last for the edge, so its orientation is wrong, need to revert the edge
 471       anEdge.Reverse();
 472       break;
 473     }
 474     if (aVertex.TShape() != theSpliceVertex.TShape())
 475     {
 476       aCurVertChanged = aVertex;
 477       isCurVertChanged = true;
 478     }
 479   }
 480   theSpliceVertex = isCurVertChanged ? aCurVertChanged : aVertExp.Current();
 481
 482   theBuilder.Add(theWire, anEdge);
 483 }
 484
 485 void createFace(const TopoDS_Shape&                      theStartVertex,
 486                 const std::list<TopoDS_Shape>::iterator& theStartEdge,
 487                 const std::list<TopoDS_Shape>::iterator& theEndOfEdges,
 488                 const gp_Pln&                            thePlane,
 489                       TopoDS_Face&                       theResFace)
 490 {
 491   TopoDS_Wire aResWire;
 492   BRep_Builder aBuilder;
 493   aBuilder.MakeWire(aResWire);
 494
 495   TopoDS_Shape aCurVertex = theStartVertex;
 496   std::list<TopoDS_Shape>::const_iterator anEdgeIter = theStartEdge;
 497   for ( ; anEdgeIter != theEndOfEdges; anEdgeIter++)
 498   {
 499     TopoDS_Edge anEdge = *((TopoDS_Edge*)(&(*anEdgeIter)));
 500     addEdgeToWire(anEdge, aBuilder, aCurVertex, aResWire);
 501   }
 502
 503   BRepBuilderAPI_MakeFace aFaceBuilder(thePlane, aResWire);
 504   if (aFaceBuilder.Error() == BRepBuilderAPI_FaceDone)
 505     theResFace = aFaceBuilder.Face();
 506 }
 507
 508 void createWireList(const TopoDS_Shape&                      theStartVertex,
 509                     const std::list<TopoDS_Shape>::iterator& theStartEdge,
 510                     const std::list<TopoDS_Shape>::iterator& theEndOfEdges,
 511                     const std::set<Handle(TopoDS_TShape)>&   theEdgesInLoops,
 512                           std::list<TopoDS_Wire>&            theResWires)
 513 {
 514   BRep_Builder aBuilder;
 515   bool needNewWire = true;
 516   TopoDS_Shape aCurVertex = theStartVertex;
 517
 518   std::list<TopoDS_Shape>::iterator anIter = theStartEdge;
 519   while (anIter != theEndOfEdges)
 520   {
 521     while (anIter != theEndOfEdges && needNewWire &&
 522            theEdgesInLoops.count(anIter->TShape()) != 0)
 523     {
 524       TopExp_Explorer aVertExp(*anIter, TopAbs_VERTEX);
 525       for ( ; aVertExp.More(); aVertExp.Next())
 526         if (aVertExp.Current().TShape() != aCurVertex.TShape())
 527         {
 528           aCurVertex = aVertExp.Current();
 529           break;
 530         }
 531       anIter++;
 532     }
 533     if (anIter == theEndOfEdges)
 534       break;
 535
 536     if (needNewWire)
 537     { // The new wire should be created
 538       TopoDS_Wire aWire;
 539       aBuilder.MakeWire(aWire);
 540       theResWires.push_back(aWire);
 541       needNewWire = false;
 542     }
 543     else if (theEdgesInLoops.count(anIter->TShape()) != 0)
 544     { // There was found the edge already used in loop.
 545       // Current wire should be released and new one should started
 546       needNewWire = true;
 547       continue;
 548     }
 549
 550     TopoDS_Edge anEdge = *((TopoDS_Edge*)(&(*anIter)));
 551     addEdgeToWire(anEdge, aBuilder, aCurVertex, theResWires.back());
 552     anIter++;
 553   }
 554 }
 555
 556
 557 gp_Dir getOuterEdgeDirection(const TopoDS_Shape& theEdge,
 558                              const TopoDS_Shape& theVertex)
 559 {
 560   const Handle(BRep_TVertex)& aVertex = (const Handle(BRep_TVertex)&)theVertex.TShape();
 561   gp_Pnt aVertexPnt = aVertex->Pnt();
 562
 563   const Handle(BRep_TEdge)& anEdge = (const Handle(BRep_TEdge)&)theEdge.TShape();
 564
 565   // Convert the edge to the curve to calculate the tangency.
 566   // There should be only one curve in the edge.
 567   Handle(BRep_Curve3D) aEdCurve =
 568     Handle(BRep_Curve3D)::DownCast(anEdge->Curves().First());
 569   double aFirst, aLast;
 570   aEdCurve->Range(aFirst, aLast);
 571   Handle(Geom_Curve) aCurve = aEdCurve->Curve3D();
 572
 573   gp_Pnt aPnt;
 574   gp_Vec aTang;
 575   aCurve->D1(aFirst + shift, aPnt, aTang);
 576   aCurve->D0(aFirst, aPnt);
 577   if (aVertexPnt.IsEqual(aPnt, tolerance))
 578     return gp_Dir(aTang.Reversed());
 579
 580   aCurve->D1(aLast - shift, aPnt, aTang);
 581   return gp_Dir(aTang);
 582 }
 583
 584 void removeWasteEdges(
 585                 std::list<TopoDS_Shape>::iterator&  theStartVertex,
 586                 std::list<TopoDS_Shape>::iterator&  theStartEdge,
 587           const std::list<TopoDS_Shape>::iterator&  theEndOfVertexes,
 588           const std::list<TopoDS_Shape>::iterator&  theEndOfEdges,
 589           BOPCol_IndexedDataMapOfShapeListOfShape&  theMapVE)
 590 {
 591   bool isVertStep = true;
 592   while (theStartVertex != theEndOfVertexes && theStartEdge != theEndOfEdges)
 593   {
 594     BOPCol_ListOfShape& aBunch = theMapVE.ChangeFromKey(*theStartVertex);
 595     BOPCol_ListOfShape::Iterator anApprEdge(aBunch);
 596     for ( ; anApprEdge.More(); anApprEdge.Next())
 597       if (anApprEdge.Value() == *theStartEdge)
 598         break;
 599     if (anApprEdge.More())
 600       aBunch.Remove(anApprEdge);
 601
 602     if (isVertStep)
 603       theStartVertex++;
 604     else
 605     {
 606       theStartEdge++;
 607       // check current vertex to be a branching point
 608       // if so, it will be a new starting point to find a loop
 609       if (aBunch.Size() > 1)
 610         break;
 611     }
 612     isVertStep = !isVertStep;
 613   }
 614
 615   // The map of vertex-edges may be changed
 616   BOPCol_IndexedDataMapOfShapeListOfShape aMapVECopy;
 617   BOPCol_IndexedDataMapOfShapeListOfShape::Iterator aMapIter(theMapVE);
 618   for (int ind = 1; aMapIter.More(); aMapIter.Next(), ind++)
 619     if (!aMapIter.Value().IsEmpty())
 620       aMapVECopy.Add(theMapVE.FindKey(ind), aMapIter.Value());
 621   theMapVE.Clear();
 622   theMapVE.Exchange(aMapVECopy);
 623 }
 624