23068: [CEA 1505] Be able to keep meshing in 2D after having merged the nodes in 1D

src/SMESH/SMESH_Algo.cxx

@@ -432,16 +432,14 @@ bool SMESH_Algo::GetSortedNodesOnEdge(const SMESHDS_Mesh*                   theM
       const SMDS_EdgePosition* epos =
         static_cast<const SMDS_EdgePosition*>(node->GetPosition());
       theNodes.insert( theNodes.end(), make_pair( epos->GetUParameter(), node ));
-      //MESSAGE("U " << epos->GetUParameter() << " ID " << node->GetID());
       ++nbNodes;
     }
   }
   // add vertex nodes
   TopoDS_Vertex v1, v2;
   TopExp::Vertices(theEdge, v1, v2);
-  const SMDS_MeshNode* n1 = VertexNode( v1, (SMESHDS_Mesh*) theMesh );
+  const SMDS_MeshNode* n1 = VertexNode( v1, eSubMesh, 0 );
-  const SMDS_MeshNode* n2 = VertexNode( v2, (SMESHDS_Mesh*) theMesh );
+  const SMDS_MeshNode* n2 = VertexNode( v2, eSubMesh, 0 );
-  //MESSAGE("Vertices ID " << n1->GetID() << " " << n2->GetID());
   Standard_Real f, l;
   BRep_Tool::Range(theEdge, f, l);
   if ( v1.Orientation() != TopAbs_FORWARD )
@@ -614,6 +612,118 @@ const SMDS_MeshNode* SMESH_Algo::VertexNode(const TopoDS_Vertex& V,
   return 0;
 }
 
+//=======================================================================
+/*!
+ * \brief Return the node built on a vertex.
+ *        A node moved to other geometry by MergeNodes() is also returned.
+ * \param V - the vertex
+ * \param mesh - mesh
+ * \retval const SMDS_MeshNode* - found node or NULL
+ */
+//=======================================================================
+
+const SMDS_MeshNode* SMESH_Algo::VertexNode(const TopoDS_Vertex& V,
+                                            const SMESH_Mesh*    mesh)
+{
+  const SMDS_MeshNode* node = VertexNode( V, mesh->GetMeshDS() );
+
+  if ( !node && mesh->HasModificationsToDiscard() )
+  {
+    PShapeIteratorPtr edgeIt = SMESH_MesherHelper::GetAncestors( V, *mesh, TopAbs_EDGE );
+    while ( const TopoDS_Shape* edge = edgeIt->next() )
+      if ( SMESHDS_SubMesh* edgeSM = mesh->GetMeshDS()->MeshElements( *edge ))
+        if ( edgeSM->NbElements() > 0 )
+          return VertexNode( V, edgeSM, mesh, /*checkV=*/false );
+  }
+  return node;
+}
+
+//=======================================================================
+/*!
+ * \brief Return the node built on a vertex.
+ *        A node moved to other geometry by MergeNodes() is also returned.
+ * \param V - the vertex
+ * \param edgeSM - sub-mesh of a meshed EDGE sharing the vertex
+ * \param checkV - if \c true, presence of a node on the vertex is checked
+ * \retval const SMDS_MeshNode* - found node or NULL
+ */
+//=======================================================================
+
+const SMDS_MeshNode* SMESH_Algo::VertexNode(const TopoDS_Vertex&   V,
+                                            const SMESHDS_SubMesh* edgeSM,
+                                            const SMESH_Mesh*      mesh,
+                                            const bool             checkV)
+{
+  const SMDS_MeshNode* node = checkV ? VertexNode( V, edgeSM->GetParent() ) : 0;
+
+  if ( !node && edgeSM )
+  {
+    // find nodes not shared by mesh segments
+    typedef set< const SMDS_MeshNode* >                       TNodeSet;
+    typedef map< const SMDS_MeshNode*, const SMDS_MeshNode* > TNodeMap;
+    TNodeMap notSharedNodes;
+    TNodeSet otherShapeNodes;
+    vector< const SMDS_MeshNode* > segNodes(3);
+    SMDS_ElemIteratorPtr segIt = edgeSM->GetElements();
+    while ( segIt->more() )
+    {
+      const SMDS_MeshElement* seg = segIt->next();
+      if ( seg->GetType() != SMDSAbs_Edge )
+        return node;
+      segNodes.assign( seg->begin_nodes(), seg->end_nodes() );
+      for ( int i = 0; i < 2; ++i )
+      {
+        const SMDS_MeshNode* n1 = segNodes[i];
+        const SMDS_MeshNode* n2 = segNodes[1-i];
+        pair<TNodeMap::iterator, bool> it2new = notSharedNodes.insert( make_pair( n1, n2 ));
+        if ( !it2new.second ) // n encounters twice
+          notSharedNodes.erase( it2new.first );
+        if ( n1->getshapeId() != edgeSM->GetID() )
+          otherShapeNodes.insert( n1 );
+      }
+    }
+    if ( otherShapeNodes.size() == 1 && notSharedNodes.empty() ) // a closed EDGE
+      return *otherShapeNodes.begin();
+
+    if ( notSharedNodes.size() == 2 ) // two end nodes found
+    {
+      SMESHDS_Mesh*  meshDS = edgeSM->GetParent();
+      const TopoDS_Shape& E = meshDS->IndexToShape( edgeSM->GetID() );
+      if ( E.IsNull() || E.ShapeType() != TopAbs_EDGE )
+        return node;
+      const SMDS_MeshNode* n1 = notSharedNodes.begin ()->first;
+      const SMDS_MeshNode* n2 = notSharedNodes.rbegin()->first;
+      TopoDS_Shape S1 = SMESH_MesherHelper::GetSubShapeByNode( n1, meshDS );
+      if ( S1.ShapeType() == TopAbs_VERTEX && SMESH_MesherHelper::IsSubShape( S1, E ))
+        return n2;
+      TopoDS_Shape S2 = SMESH_MesherHelper::GetSubShapeByNode( n2, meshDS );
+      if ( S2.ShapeType() == TopAbs_VERTEX && SMESH_MesherHelper::IsSubShape( S2, E ))
+        return n1;
+      if ( edgeSM->NbElements() <= 2 || !mesh ) // one-two segments
+      {
+        gp_Pnt pV = BRep_Tool::Pnt( V );
+        double dist1 = pV.SquareDistance( SMESH_TNodeXYZ( n1 ));
+        double dist2 = pV.SquareDistance( SMESH_TNodeXYZ( n2 ));
+        return dist1 < dist2 ? n1 : n2;
+      }
+      if ( mesh )
+      {
+        SMESH_MesherHelper helper( const_cast<SMESH_Mesh&>( *mesh ));
+        const SMDS_MeshNode* n1i = notSharedNodes.begin ()->second;
+        const SMDS_MeshNode* n2i = notSharedNodes.rbegin()->second;
+        const TopoDS_Edge&  edge = TopoDS::Edge( E );
+        bool  posOK = true;
+        double pos1 = helper.GetNodeU( edge, n1i, n2i, &posOK );
+        double pos2 = helper.GetNodeU( edge, n2i, n1i, &posOK );
+        double posV = BRep_Tool::Parameter( V, edge );
+        if ( Abs( pos1 - posV ) < Abs( pos2 - posV )) return n1;
+        else                                          return n2;
+      }
+    }
+  }
+  return node;
+}
+
 //=======================================================================
 //function : GetMeshError
 //purpose  : Finds topological errors of a sub-mesh

src/SMESH/SMESH_Algo.hxx

@@ -313,6 +313,7 @@ public:
    * \param theEdge - The geometrical edge of interest
    * \param theParams - The resulting vector of sorted node parameters
    * \retval bool - false if not all parameters are OK
+   * \warning Nodes moved to other geometry by MergeNodes() are NOT returned.
    */
   static bool GetNodeParamOnEdge(const SMESHDS_Mesh*     theMesh,
                                  const TopoDS_Edge&      theEdge,
@@ -325,17 +326,14 @@ public:
    * \param ignoreMediumNodes - to store medium nodes of quadratic elements or not
    * \param typeToCheck - type of elements to check for medium nodes
    * \retval bool - false if not all parameters are OK
+   * \warning Nodes moved to other geometry by MergeNodes() are NOT returned.
    */
   static bool GetSortedNodesOnEdge(const SMESHDS_Mesh*                        theMesh,
                                    const TopoDS_Edge&                         theEdge,
                                    const bool                                 ignoreMediumNodes,
                                    std::map< double, const SMDS_MeshNode* > & theNodes,
                                    const SMDSAbs_ElementType                  typeToCheck = SMDSAbs_All);
-  /*!
+
-   * Moved to SMESH_MesherHelper
-   */
-  // static bool IsReversedSubMesh (const TopoDS_Face&  theFace,
-  //                                SMESHDS_Mesh*       theMeshDS);
   /*!
    * \brief Compute length of an edge
     * \param E - the edge
@@ -343,7 +341,6 @@ public:
    */
   static double EdgeLength(const TopoDS_Edge & E);
 
-  //static int NumberOfWires(const TopoDS_Shape& S);
   int NumberOfPoints(SMESH_Mesh& aMesh,const TopoDS_Wire& W);
 
   /*!
@@ -372,11 +369,34 @@ public:
   /*!
    * \brief Return the node built on a vertex
     * \param V - the vertex
-    * \param meshDS - mesh
+    * \param meshDS - mesh data structure
     * \retval const SMDS_MeshNode* - found node or NULL
    */
   static const SMDS_MeshNode* VertexNode(const TopoDS_Vertex& V, const SMESHDS_Mesh* meshDS);
 
+  /*!
+   * \brief Return the node built on a vertex.
+   *        A node moved to other geometry by MergeNodes() is also returned.
+    * \param V - the vertex
+    * \param mesh - mesh
+    * \retval const SMDS_MeshNode* - found node or NULL
+   */
+  static const SMDS_MeshNode* VertexNode(const TopoDS_Vertex& V, const SMESH_Mesh* mesh);
+
+  /*!
+   * \brief Return the node built on a vertex.
+   *        A node moved to other geometry by MergeNodes() is also returned.
+    * \param V - the vertex
+    * \param edgeSM - sub-mesh of a meshed EDGE sharing the vertex
+    * \param mesh - the mesh
+    * \param checkV - if \c true, presence of a node on the vertex is checked
+    * \retval const SMDS_MeshNode* - found node or NULL
+   */
+  static const SMDS_MeshNode* VertexNode(const TopoDS_Vertex&   V,
+                                         const SMESHDS_SubMesh* edgeSM,
+                                         const SMESH_Mesh*      mesh,
+                                         const bool             checkV=true);
+
   enum EMeshError { MEr_OK = 0, MEr_HOLES, MEr_BAD_ORI, MEr_EMPTY };
 
   /*!

src/SMESH/SMESH_Mesh.cxx

@@ -1117,7 +1117,7 @@ throw(SALOME_Exception)
 
 //================================================================================
 /*!
- * \brief Return submeshes of groups containing the given sub-shape
+ * \brief Return sub-meshes of groups containing the given sub-shape
  */
 //================================================================================
 
@@ -1131,7 +1131,7 @@ SMESH_Mesh::GetGroupSubMeshesContaining(const TopoDS_Shape & aSubShape) const
   if ( !subMesh )
     return found;
 
-  // submeshes of groups have max IDs, so search from the map end
+  // sub-meshes of groups have max IDs, so search from the map end
   SMESH_subMeshIteratorPtr smIt( _subMeshHolder->GetIterator( /*reverse=*/true ) );
   while ( smIt->more() ) {
     SMESH_subMesh*    sm = smIt->next();
@@ -1158,6 +1158,12 @@ SMESH_subMeshIteratorPtr smIt( _subMeshHolder->GetIterator( /*reverse=*/true ) )
           found.push_back( mainSM );
       }
   }
+  else // issue 0023068
+  {
+    if ( SMESH_subMesh * mainSM = GetSubMeshContaining(1) )
+      if ( mainSM->GetSubShape().ShapeType() == TopAbs_COMPOUND )
+        found.push_back( mainSM );
+  }
   return found;
 }
 //=======================================================================

src/SMESH/SMESH_MesherHelper.cxx

@@ -191,8 +191,8 @@ bool SMESH_MesherHelper::IsQuadraticSubMesh(const TopoDS_Shape& aSh)
     }
   }
 
-  if ( nbOldLinks == myTLinkNodeMap.size() )
+  // if ( nbOldLinks == myTLinkNodeMap.size() ) -- 0023068
-    myCreateQuadratic = false;
+  //   myCreateQuadratic = false;
 
   if(!myCreateQuadratic) {
     myTLinkNodeMap.clear();

src/SMESH/SMESH_subMesh.cxx

@@ -455,7 +455,8 @@ const map < int, SMESH_subMesh * >& SMESH_subMesh::DependsOn()
  */
 //================================================================================
 
-namespace {
+namespace
+{
   int dependsOnMapKey( const SMESH_subMesh* sm )
   {
     int type = sm->GetSubShape().ShapeType();
@@ -479,6 +480,8 @@ void SMESH_subMesh::insertDependence(const TopoDS_Shape aShape,
   for ( ; sub.More(); sub.Next() )
   {
     SMESH_subMesh *aSubMesh = _father->GetSubMesh( sub.Current() );
+    if ( aSubMesh->GetId() == 0 )
+      continue;  // not a sub-shape of the shape to mesh
     int cle = dependsOnMapKey( aSubMesh );
     if ( _mapDepend.find( cle ) == _mapDepend.end())
     {
@@ -597,6 +600,7 @@ SMESH_Hypothesis::Hypothesis_Status
   // le retour des evenement father n'indiquent pas que add ou remove fait
 
   SMESH_Hypothesis::Hypothesis_Status aux_ret, ret = SMESH_Hypothesis::HYP_OK;
+  if ( _Id == 0 ) return ret; // not a sub-shape of the shape to mesh
 
   SMESHDS_Mesh* meshDS =_father->GetMeshDS();
   SMESH_Algo*   algo   = 0;
@@ -1004,7 +1008,7 @@ SMESH_Hypothesis::Hypothesis_Status
   // detect algorithm hiding
   //
   if ( ret == SMESH_Hypothesis::HYP_OK && 
-       ( event == ADD_ALGO || event == ADD_FATHER_ALGO ) &&
+       ( event == ADD_ALGO || event == ADD_FATHER_ALGO ) && algo && 
        algo->GetName() == anHyp->GetName() )
   {
     // is algo hidden?

src/SMESHDS/SMESHDS_SubMesh.hxx

@@ -73,7 +73,7 @@ class SMESHDS_EXPORT SMESHDS_SubMesh
   int getSize();
   void compactList();
 
-  SMESHDS_Mesh *GetParent()   { return myParent; }
+  SMESHDS_Mesh* GetParent() const { return const_cast< SMESHDS_Mesh*>( myParent ); }
   int           GetID()     const { return myIndex; }
 
  private:

src/StdMeshers/StdMeshers_FaceSide.cxx

@@ -79,8 +79,6 @@ StdMeshers_FaceSide::StdMeshers_FaceSide(const TopoDS_Face&   theFace,
 //================================================================================
 /*!
  * \brief Constructor of a side of several edges
-  * \param theFace - the face
-  * \param theEdge - the edge
  */
 //================================================================================
 
@@ -101,6 +99,7 @@ StdMeshers_FaceSide::StdMeshers_FaceSide(const TopoDS_Face&   theFace,
   myNormPar.resize   ( nbEdges );
   myEdgeLength.resize( nbEdges );
   myIsUniform.resize ( nbEdges, true );
+  myFace               = theFace;
   myLength             = 0;
   myNbPonits           = myNbSegments = 0;
   myProxyMesh          = theProxyMesh;
@@ -132,25 +131,6 @@ StdMeshers_FaceSide::StdMeshers_FaceSide(const TopoDS_Face&   theFace,
     if ( myEdge[i].Orientation() == TopAbs_REVERSED )
       std::swap( myFirst[i], myLast[i] );
 
-    if ( const SMESHDS_SubMesh* sm = myProxyMesh->GetSubMesh( *edge )) {
-      int nbN = sm->NbNodes();
-      if ( theIgnoreMediumNodes ) {
-        SMDS_ElemIteratorPtr elemIt = sm->GetElements();
-        if ( elemIt->more() && elemIt->next()->IsQuadratic() )
-          nbN -= sm->NbElements();
-      }
-      myNbPonits += nbN;
-      myNbSegments += sm->NbElements();
-    }
-
-    // TopExp::FirstVertex() and TopExp::LastVertex() return NULL from INTERNAL edge
-    vExp.Initialize( *edge );
-    if ( vExp.Value().Orientation() == TopAbs_REVERSED ) vExp.Next();
-    if ( SMESH_Algo::VertexNode( TopoDS::Vertex( vExp.Value()), meshDS ))
-      myNbPonits += 1; // for the first end
-    else
-      myMissingVertexNodes = true;
-
     // check if the edge has a non-uniform parametrization (issue 0020705)
     if ( !myC2d[i].IsNull() )
     {
@@ -159,7 +139,8 @@ StdMeshers_FaceSide::StdMeshers_FaceSide(const TopoDS_Face&   theFace,
         Geom2dAdaptor_Curve A2dC( myC2d[i],
                                   std::min( myFirst[i], myLast[i] ),
                                   std::max( myFirst[i], myLast[i] ));
-        double p2 = myFirst[i]+(myLast[i]-myFirst[i])/2., p4 = myFirst[i]+(myLast[i]-myFirst[i])/4.;
+        double p2 = myFirst[i]+(myLast[i]-myFirst[i])/2.;
+        double p4 = myFirst[i]+(myLast[i]-myFirst[i])/4.;
         double d2 = GCPnts_AbscissaPoint::Length( A2dC, myFirst[i], p2 );
         double d4 = GCPnts_AbscissaPoint::Length( A2dC, myFirst[i], p4 );
         //cout<<"len = "<<len<<"  d2 = "<<d2<<"  fabs(2*d2/len-1.0) = "<<fabs(2*d2/len-1.0)<<endl;
@@ -174,21 +155,15 @@ StdMeshers_FaceSide::StdMeshers_FaceSide(const TopoDS_Face&   theFace,
         myC3dAdaptor[i].Load( C3d, 0, 0.5 * BRep_Tool::Tolerance( V ));
       }
     }
-    // reverse a proxy submesh
+    // reverse a proxy sub-mesh
     if ( !theIsForward )
       reverseProxySubmesh( myEdge[i] );
 
   } // loop on edges
 
-  vExp.Initialize( theEdges.back() );
+  // count nodes and segments
-  if ( vExp.Value().Orientation() != TopAbs_REVERSED ) vExp.Next();
+  NbPoints( /*update=*/true );
-  if ( vExp.More() )
+
-  {
-    if ( SMESH_Algo::VertexNode( TopoDS::Vertex( vExp.Value()), meshDS ))
-      myNbPonits++; // for the last end
-    else
-      myMissingVertexNodes = true;
-  }
   if ( nbEdges > 1 && myLength > DBL_MIN ) {
     const double degenNormLen = 1.e-5;
     double totLength = myLength;
@@ -209,8 +184,6 @@ StdMeshers_FaceSide::StdMeshers_FaceSide(const TopoDS_Face&   theFace,
 //================================================================================
 /*!
  * \brief Constructor of a side for vertex using data from other FaceSide
- *  \param theVertex - the vertex
- *  \param theSide - the side
  */
 //================================================================================
 
@@ -271,6 +244,7 @@ StdMeshers_FaceSide::StdMeshers_FaceSide(UVPtStructVec&     theSideNodes,
   myMissingVertexNodes = myIgnoreMediumNodes = false;
   myDefaultPnt2d.SetCoord( 1e100, 1e100 );
 
+  myFace       = theFace;
   myPoints     = theSideNodes;
   myNbPonits   = myPoints.size();
   myNbSegments = myNbPonits + 1;
@@ -332,10 +306,11 @@ StdMeshers_FaceSide::StdMeshers_FaceSide(UVPtStructVec&     theSideNodes,
 const vector<UVPtStruct>& StdMeshers_FaceSide::GetUVPtStruct(bool   isXConst,
                                                              double constValue) const
 {
-  if ( myPoints.empty() ) {
+  if ( myPoints.empty() )
-
+  {
     if ( NbEdges() == 0 ) return myPoints;
 
+    StdMeshers_FaceSide* me = const_cast< StdMeshers_FaceSide* >( this );
     SMESHDS_Mesh*    meshDS = myProxyMesh->GetMeshDS();
     SMESH_MesherHelper helper( *myProxyMesh->GetMesh() );
     bool paramOK;
@@ -344,9 +319,14 @@ const vector<UVPtStruct>& StdMeshers_FaceSide::GetUVPtStruct(bool   isXConst,
     // sort nodes of all edges putting them into a map
 
     map< double, const SMDS_MeshNode*>            u2node;
+    vector< pair< double, const SMDS_MeshNode*> > u2nodeVec;
+    vector<const SMDS_MeshNode*>                  nodes;
+    set<const SMDS_MeshNode*>                     vertexNodes;
     vector< const SMESH_ProxyMesh::SubMesh* >     proxySubMesh( myEdge.size() );
     int nbProxyNodes = 0;
-    for ( size_t iE = 0; iE < myEdge.size(); ++iE )
+    size_t iE;
+
+    for ( iE = 0; iE < myEdge.size(); ++iE )
     {
       proxySubMesh[iE] = myProxyMesh->GetProxySubMesh( myEdge[iE] );
       if ( proxySubMesh[iE] )
@@ -361,74 +341,86 @@ const vector<UVPtStruct>& StdMeshers_FaceSide::GetUVPtStruct(bool   isXConst,
           continue;
         }
       }
-      // Put 1st vertex node of a current edge
+
-      TopoDS_Vertex VV[2]; // TopExp::FirstVertex() returns NULL for INTERNAL edge
+      // Add 1st vertex node of a current edge
-      VV[0] = SMESH_MesherHelper::IthVertex( 0, myEdge[iE]);
+      const SMDS_MeshNode* node = VertexNode( iE );
-      VV[1] = SMESH_MesherHelper::IthVertex( 1, myEdge[iE]);
+      const double  prevNormPar = ( iE == 0 ? 0 : myNormPar[ iE-1 ]); // normalized param
-      const SMDS_MeshNode* node = SMESH_Algo::VertexNode( VV[0], meshDS );
+      if ( node ) // nodes on internal vertices may be missing
-      double prevNormPar = ( iE == 0 ? 0 : myNormPar[ iE-1 ]); // normalized param
+      {
-      if ( node ) { // nodes on internal vertices may be missing
+        if ( vertexNodes.insert( node ).second )
           u2node.insert( u2node.end(), make_pair( prevNormPar, node ));
       }
-      else if ( iE == 0 ) {
+      else if ( iE == 0 )
-        MESSAGE(" NO NODE on VERTEX" );
+      {
+        if ( nodes.empty() ) {
+          for ( ++iE; iE < myEdge.size(); ++iE )
+            if (( node = VertexNode( iE ))) {
+              u2node.insert( make_pair( prevNormPar, node ));
+              break;
+            }
+          --iE;
+        }
+        if ( !node )
           return myPoints;
+        vertexNodes.insert( node );
       }
 
-      // Put internal nodes
+      // Add internal nodes
-      if ( const SMESHDS_SubMesh* sm = myProxyMesh->GetSubMesh( myEdge[iE] ))
+      nodes.clear();
+      if ( !GetEdgeNodes( iE, nodes, /*v0=*/false, /*v1=*/false ))
+        return myPoints;
+      if ( !nodes.empty() )
       {
-        vector< pair< double, const SMDS_MeshNode*> > u2nodeVec;
+        u2nodeVec.clear();
-        u2nodeVec.reserve( sm->NbNodes() );
-        SMDS_NodeIteratorPtr nItr = sm->GetNodes();
         double paramSize = myLast[iE] - myFirst[iE];
         double r         = myNormPar[iE] - prevNormPar;
         helper.SetSubShape( myEdge[iE] );
         helper.ToFixNodeParameters( true );
         if ( !myIsUniform[iE] )
-          while ( nItr->more() )
+          for ( size_t i = 0; i < nodes.size(); ++i )
           {
-            const SMDS_MeshNode* node = nItr->next();
+            double     u = helper.GetNodeU( myEdge[iE], nodes[i], 0, &paramOK );
-            if ( myIgnoreMediumNodes && SMESH_MeshEditor::IsMedium( node, SMDSAbs_Edge ))
+            double aLenU = GCPnts_AbscissaPoint::Length( me->myC3dAdaptor[iE], myFirst[iE], u );
-              continue;
-            double u = helper.GetNodeU( myEdge[iE], node, 0, &paramOK );
-            double aLenU = GCPnts_AbscissaPoint::Length
-              ( const_cast<GeomAdaptor_Curve&>( myC3dAdaptor[iE]), myFirst[iE], u );
             if ( myEdgeLength[iE] < aLenU ) // nonregression test "3D_mesh_NETGEN/G6"
             {
               u2nodeVec.clear();
               break;
             }
             double normPar = prevNormPar + r * aLenU / myEdgeLength[iE];
-            u2nodeVec.push_back( make_pair( normPar, node ));
+            u2nodeVec.push_back( make_pair( normPar, nodes[i] ));
           }
-        nItr = sm->GetNodes();
         if ( u2nodeVec.empty() )
-          while ( nItr->more() )
+          for ( size_t i = 0; i < nodes.size(); ++i )
           {
-            const SMDS_MeshNode* node = nItr->next();
+            double u = helper.GetNodeU( myEdge[iE], nodes[i], 0, &paramOK );
-            if ( myIgnoreMediumNodes && SMESH_MeshEditor::IsMedium( node, SMDSAbs_Edge ))
-              continue;
-            double u = helper.GetNodeU( myEdge[iE], node, 0, &paramOK );
-
             // paramSize is signed so orientation is taken into account
             double normPar = prevNormPar + r * ( u - myFirst[iE] ) / paramSize;
-            u2nodeVec.push_back( make_pair( normPar, node ));
+            u2nodeVec.push_back( make_pair( normPar, nodes[i] ));
           }
         for ( size_t j = 0; j < u2nodeVec.size(); ++j )
           u2node.insert( u2node.end(), u2nodeVec[j] );
       }
+    } // loop on myEdge's
 
-      // Put 2nd vertex node for a last edge
+    if ( u2node.empty() ) return myPoints;
-      if ( iE+1 == myEdge.size() ) {
+
-        node = SMESH_Algo::VertexNode( VV[1], meshDS );
+    // Add 2nd VERTEX node for a last EDGE
-        if ( !node ) {
+    {
-          MESSAGE(" NO NODE on VERTEX" );
+      const SMDS_MeshNode* node;
+      if ( IsClosed() )
+        node = u2node.begin()->second;
+      else
+      {
+        node = VertexNode( iE );
+        while ( !node && iE > 0 )
+          node = VertexNode( --iE );
+        if ( !node )
           return myPoints;
       }
+      if ( u2node.rbegin()->second == node )
+        u2node.erase( --u2node.end() );
       u2node.insert( u2node.end(), make_pair( 1., node ));
     }
-    } // loop on myEdge's
 
     if ( u2node.size() + nbProxyNodes != myNbPonits &&
          u2node.size() + nbProxyNodes != NbPoints( /*update=*/true ))
@@ -440,7 +432,7 @@ const vector<UVPtStruct>& StdMeshers_FaceSide::GetUVPtStruct(bool   isXConst,
 
     // fill array of UVPtStruct
 
-    UVPtStructVec& points = const_cast< UVPtStructVec& >( myPoints );
+    UVPtStructVec& points = me->myPoints;
     points.resize( myNbPonits );
 
     int iPt = 0;
@@ -487,7 +479,7 @@ const vector<UVPtStruct>& StdMeshers_FaceSide::GetUVPtStruct(bool   isXConst,
           // -- U ----------------------------------------------
           const SMDS_EdgePosition* epos =
             dynamic_cast<const SMDS_EdgePosition*>(uvPt.node->GetPosition());
-          if ( epos ) {
+          if ( epos && uvPt.node->getshapeId() == myEdgeID[iE] ) {
             uvPt.param = epos->GetUParameter();
           }
           else {
@@ -577,66 +569,102 @@ const vector<UVPtStruct>& StdMeshers_FaceSide::SimulateUVPtStruct(int    nbSeg,
 //purpose  : Return nodes in the order they encounter while walking along the side
 //=======================================================================
 
-std::vector<const SMDS_MeshNode*> StdMeshers_FaceSide::GetOrderedNodes() const
+std::vector<const SMDS_MeshNode*> StdMeshers_FaceSide::GetOrderedNodes(int theEdgeInd) const
 {
   vector<const SMDS_MeshNode*> resultNodes;
-  if ( myPoints.empty() )
+  if ( myPoints.empty() || ( theEdgeInd >= 0 && NbEdges() > 0 ))
   {
     if ( NbEdges() == 0 ) return resultNodes;
 
     SMESHDS_Mesh* meshDS = myProxyMesh->GetMeshDS();
     SMESH_MesherHelper helper(*myProxyMesh->GetMesh());
-    bool paramOK;
+    bool paramOK = true;
 
     // Sort nodes of all edges putting them into a map
 
     map< double, const SMDS_MeshNode*>        u2node;
-    for ( int i = 0; i < myEdge.size(); ++i )
+    vector<const SMDS_MeshNode*>              nodes;
+    set<const SMDS_MeshNode*>                 vertexNodes;
+    int iE = 0, iEnd = myEdge.size();
+    if ( theEdgeInd >= 0 )
     {
-      // Put 1st vertex node of a current edge
+      iE   = theEdgeInd % NbEdges();
-      TopoDS_Vertex VV[2]; // TopExp::FirstVertex() returns NULL for INTERNAL edge
+      iEnd = iE + 1;
-      VV[0] = SMESH_MesherHelper::IthVertex( 0, myEdge[i]);
+    }
-      VV[1] = SMESH_MesherHelper::IthVertex( 1, myEdge[i]);
+    for ( iE = 0; iE < iEnd; ++iE )
-      const SMDS_MeshNode* node = SMESH_Algo::VertexNode( VV[0], meshDS );
+    {
-      double prevNormPar = ( i == 0 ? 0 : myNormPar[ i-1 ]); // normalized param
+      double prevNormPar = ( iE == 0 ? 0 : myNormPar[ iE-1 ]); // normalized param
+
+      const SMESH_ProxyMesh::SubMesh* proxySM = myProxyMesh->GetProxySubMesh( myEdge[iE] );
+      if ( proxySM )
+      {
+        const UVPtStructVec& points = proxySM->GetUVPtStructVec();
+        for ( size_t i = 0; i < points.size(); ++i )
+          u2node.insert( make_pair( prevNormPar + points[i].normParam, points[i].node ));
+        continue;
+      }
+
+      // Add 1st vertex node of a current EDGE
+      const SMDS_MeshNode* node = VertexNode( iE );
       if ( node ) { // nodes on internal vertices may be missing
+        if ( vertexNodes.insert( node ).second )
           u2node.insert( make_pair( prevNormPar, node ));
       }
-      else if ( i == 0 ) {
+      else if ( iE == 0 )
-        MESSAGE(" NO NODE on VERTEX" );
+      {
+        if ( nodes.empty() ) {
+          for ( ++iE; iE < iEnd; ++iE )
+            if (( node = VertexNode( iE ))) {
+              u2node.insert( make_pair( prevNormPar, node ));
+              break;
+            }
+          --iE;
+        }
+        if ( !node )
           return resultNodes;
+        vertexNodes.insert( node );
       }
 
-      // Put internal nodes
+      // Add internal nodes
-      if ( SMESHDS_SubMesh* sm = meshDS->MeshElements( myEdge[i] ))
+      nodes.clear();
+      if ( !GetEdgeNodes( iE, nodes, /*v0=*/false, /*v1=*/false ))
+        return resultNodes;
+      if ( !nodes.empty() )
       {
-        SMDS_NodeIteratorPtr nItr = sm->GetNodes();
+        double paramSize = myLast[iE] - myFirst[iE];
-        double paramSize = myLast[i] - myFirst[i];
+        double r         = myNormPar[iE] - prevNormPar;
-        double r         = myNormPar[i] - prevNormPar;
+        helper.SetSubShape( myEdge[iE] );
-        helper.SetSubShape( myEdge[i] );
         helper.ToFixNodeParameters( true );
-        while ( nItr->more() )
+        for ( size_t i = 0; i < nodes.size(); ++i )
         {
-          const SMDS_MeshNode* node = nItr->next();
+          double u = helper.GetNodeU( myEdge[iE], nodes[i], 0, &paramOK );
-          if ( myIgnoreMediumNodes && SMESH_MeshEditor::IsMedium( node, SMDSAbs_Edge ))
-            continue;
-          double u = helper.GetNodeU( myEdge[i], node, 0, &paramOK );
-
           // paramSize is signed so orientation is taken into account
-          double normPar = prevNormPar + r * ( u - myFirst[i] ) / paramSize;
+          double normPar = prevNormPar + r * ( u - myFirst[iE] ) / paramSize;
-          u2node.insert( u2node.end(), make_pair( normPar, node ));
+          u2node.insert( u2node.end(), make_pair( normPar, nodes[i] ));
         }
       }
 
-      // Put 2nd vertex node for a last edge
+    } // loop on myEdges
-      if ( i+1 == myEdge.size() ) {
+
-        node = SMESH_Algo::VertexNode( VV[1], meshDS );
+    if ( u2node.empty() ) return resultNodes;
-        if ( !node ) {
+
+    // Add 2nd vertex node for a last EDGE
+    {
+      const SMDS_MeshNode* node;
+      if ( IsClosed() && theEdgeInd < 0 )
+        node = u2node.begin()->second;
+      else
+      {
+        node = VertexNode( iE );
+        while ( !node && iE > 0 )
+          node = VertexNode( --iE );
+        if ( !node )
           return resultNodes;
       }
+      if ( u2node.rbegin()->second == node )
+        u2node.erase( --u2node.end() );
       u2node.insert( u2node.end(), make_pair( 1., node ));
     }
-    }
 
     // Fill the result vector
 
@@ -658,6 +686,135 @@ std::vector<const SMDS_MeshNode*> StdMeshers_FaceSide::GetOrderedNodes() const
   return resultNodes;
 }
 
+//================================================================================
+/*!
+ * \brief Return (unsorted) nodes of the i-th EDGE.
+ *        Nodes moved to other geometry by MergeNodes() are also returned.
+ *  \retval bool - is OK
+ */
+//================================================================================
+
+bool StdMeshers_FaceSide::GetEdgeNodes(size_t                        i,
+                                       vector<const SMDS_MeshNode*>& nodes,
+                                       bool                          inlude1stVertex,
+                                       bool                          inludeLastVertex) const
+{
+  if ( i >= myEdge.size() )
+    return false;
+
+  SMESH_Mesh*     mesh = myProxyMesh->GetMesh();
+  SMESHDS_Mesh* meshDS = mesh->GetMeshDS();
+  SMESHDS_SubMesh*  sm = meshDS->MeshElements( myEdge[i] );
+
+  if ( inlude1stVertex )
+  {
+    const SMDS_MeshNode* n0 = VertexNode( i );
+    if ( !n0 ) return false;
+    nodes.push_back( n0 );
+  }
+
+  if ( sm && ( sm->NbElements() > 0 || sm->NbNodes() > 0 ))
+  {
+    if ( mesh->HasModificationsToDiscard() ) // check nb of nodes on the EDGE sub-mesh
+    {
+      int iQuad    = sm->GetElements()->next()->IsQuadratic();
+      int nbExpect = sm->NbElements() - 1 + iQuad * sm->NbElements();
+      if ( nbExpect != sm->NbNodes() ) // some nodes are moved from the EDGE by MergeNodes()
+      {
+        // add nodes of all segments
+        typedef set< const SMDS_MeshNode* > TNodeSet;
+        TNodeSet sharedNodes;
+        SMDS_ElemIteratorPtr segIt = sm->GetElements();
+        while ( segIt->more() )
+        {
+          const SMDS_MeshElement* seg = segIt->next();
+          if ( seg->GetType() != SMDSAbs_Edge )
+            continue;
+          for ( int i = 0; i < 3-myIgnoreMediumNodes; ++i )
+          {
+            const SMDS_MeshNode* n = seg->GetNode( i );
+            if ( i == 2 ) // medium node
+            {
+              nodes.push_back( n );
+            }
+            else
+            {
+              pair<TNodeSet::iterator, bool> it2new = sharedNodes.insert( n );
+              if ( !it2new.second ) // n encounters twice == it's on EDGE, not on VERTEX
+              {
+                nodes.push_back( n );
+                sharedNodes.erase( it2new.first );
+              }
+            }
+          }
+        }
+      }
+    }
+    if ( nodes.size() < 2 ) // add nodes assigned to the EDGE
+    {
+      SMDS_NodeIteratorPtr nItr = sm->GetNodes();
+      while ( nItr->more() )
+      {
+        const SMDS_MeshNode* n = nItr->next();
+        if ( myIgnoreMediumNodes && SMESH_MeshEditor::IsMedium( n, SMDSAbs_Edge ))
+          continue;
+        nodes.push_back( n );
+      }
+    }
+  } // if ( sm && sm->NbElements() > 0 )
+
+  if ( inludeLastVertex )
+  {
+    const SMDS_MeshNode* n1 = VertexNode( i+1 );
+    if ( !n1 ) return false;
+    nodes.push_back( n1 );
+  }
+  return true;
+}
+
+//================================================================================
+/*!
+ * \brief Return a node from the i-th VERTEX (count starts from zero)
+ *        Nodes moved to other geometry by MergeNodes() are also returned.
+ *  \param [in] i - the VERTEX index
+ *  \param [out] isMoved - returns \c true if the found node is moved by MergeNodes()
+ *  \return const SMDS_MeshNode* - the found node
+ */
+//================================================================================
+
+const SMDS_MeshNode* StdMeshers_FaceSide::VertexNode(std::size_t i, bool* isMoved) const
+{
+  TopoDS_Vertex V = ( i >= myEdge.size() ) ? LastVertex() : FirstVertex(i);
+
+  const SMDS_MeshNode* n = SMESH_Algo::VertexNode( V, myProxyMesh->GetMeshDS() );
+
+  if ( !n && !myEdge.empty() && myProxyMesh->GetMesh()->HasModificationsToDiscard() )
+  {
+    size_t iE = ( i < myEdge.size() ) ? i : myEdge.size()-1;
+    SMESHDS_SubMesh* sm = myProxyMesh->GetMeshDS()->MeshElements( myEdgeID[ iE ]);
+
+    n = SMESH_Algo::VertexNode( V, sm, myProxyMesh->GetMesh(), /*checkV=*/false );
+
+    if (( !n ) &&
+        (( i > 0 && i < NbEdges() ) || IsClosed() ))
+    {
+      iE = SMESH_MesherHelper::WrapIndex( int(i)-1, NbEdges() );
+      sm = myProxyMesh->GetMeshDS()->MeshElements( myEdgeID[ iE ]);
+      n  = SMESH_Algo::VertexNode( V, sm, myProxyMesh->GetMesh(), /*checkV=*/false );
+    }
+
+    if ( n && n->GetPosition()->GetDim() == 1 ) // check that n does not lie on an EDGE of myFace
+    {
+      TopoDS_Shape S = SMESH_MesherHelper::GetSubShapeByNode( n, myProxyMesh->GetMeshDS() );
+      if ( SMESH_MesherHelper::IsSubShape( S, myFace ))
+        n = 0; // VERTEX ignored by e.g. Composite Wire Discretization algo
+    }
+    if ( isMoved )
+      *isMoved = n;
+  }
+  return n;
+}
+
 //================================================================================
 /*!
  * \brief reverse order of vector elements
@@ -667,8 +824,7 @@ std::vector<const SMDS_MeshNode*> StdMeshers_FaceSide::GetOrderedNodes() const
 
 template <typename T > void reverse(vector<T> & vec)
 {
-  for ( int f=0, r=vec.size()-1; f < r; ++f, --r )
+  std::reverse( vec.begin(), vec.end() );
-    std::swap( vec[f], vec[r] );
 }
 
 //================================================================================
@@ -790,28 +946,29 @@ int StdMeshers_FaceSide::NbPoints(const bool update) const
 
     for ( int i = 0; i < NbEdges(); ++i )
     {
-      TopoDS_Vertex v1 = SMESH_MesherHelper::IthVertex( 0, myEdge[i] );
-      if ( SMESH_Algo::VertexNode( v1, myProxyMesh->GetMeshDS() ))
-        me->myNbPonits += 1; // for the first end
-      else
-        me->myMissingVertexNodes = true;
-    
       if ( const SMESHDS_SubMesh* sm = myProxyMesh->GetSubMesh( Edge(i) )) {
         int nbN = sm->NbNodes();
-        if ( myIgnoreMediumNodes ) {
+        if ( sm->NbElements() > 0 ) {
-          SMDS_ElemIteratorPtr elemIt = sm->GetElements();
+          nbN = sm->NbElements() - 1; // nodes can be moved to other shapes by MergeNodes()
-          if ( elemIt->more() && elemIt->next()->IsQuadratic() )
+          if ( !myIgnoreMediumNodes &&
-            nbN -= sm->NbElements();
+               sm->GetElements()->next()->IsQuadratic() )
+            nbN += sm->NbElements();
         }
         me->myNbPonits   += nbN;
         me->myNbSegments += sm->NbElements();
       }
     }
-    TopoDS_Vertex v1 = SMESH_MesherHelper::IthVertex( 1, Edge( NbEdges()-1 ));
+
-    if ( SMESH_Algo::VertexNode( v1, myProxyMesh->GetMeshDS() ))
+    std::set< const SMDS_MeshNode* > vNodes;
-      me->myNbPonits++; // for the last end
+    for ( int i = 0; i <= NbEdges(); ++i )
+      if ( const SMDS_MeshNode* n = VertexNode( i ))
+        vNodes.insert( n );
       else
         me->myMissingVertexNodes = true;
+    me->myNbPonits += vNodes.size();
+
+    if ( IsClosed() )
+      me->myNbPonits++; // closing node is repeated
   }
   return myNbPonits;
 }
@@ -928,7 +1085,7 @@ BRepAdaptor_CompCurve* StdMeshers_FaceSide::GetCurve3d() const
   for ( int i=0; i<myEdge.size(); ++i )
     aBuilder.Add( aWire, myEdge[i] );
 
-  if ( myEdge.size() == 2 && FirstVertex().IsSame( LastVertex() ))
+  if ( myEdge.size() == 2 && IsClosed() )
     aWire.Closed(true); // issue 0021141
 
   return new BRepAdaptor_CompCurve( aWire );
@@ -1118,3 +1275,13 @@ TopoDS_Vertex StdMeshers_FaceSide::LastVertex(int i) const
   return v;
 }
 
+//================================================================================
+/*!
+ * \brief Return \c true if the chain of EDGEs is closed
+ */
+//================================================================================
+
+bool StdMeshers_FaceSide::IsClosed() const
+{
+  return myEdge.empty() ? false : FirstVertex().IsSame( LastVertex() );
+}

src/StdMeshers/StdMeshers_FaceSide.hxx

@@ -191,10 +191,27 @@ public:
                                           bool   isXConst   = 0,
                                           double constValue = 0) const;
   /*!
-   * \brief Return nodes in the order they encounter while walking along the side.
+   * \brief Return nodes in the order they encounter while walking along
+   *  the while side or a specified EDGE.
     * For a closed side, the 1st point repeats at end
    */
-  std::vector<const SMDS_MeshNode*> GetOrderedNodes() const;
+  std::vector<const SMDS_MeshNode*> GetOrderedNodes(int iE=-1) const;
+
+  /*!
+   * \brief Return nodes of the i-th EDGE.
+   *        Nodes moved to other geometry by MergeNodes() are also returned.
+   * \retval bool - is OK
+   */
+  bool GetEdgeNodes(const size_t                       i,
+                    std::vector<const SMDS_MeshNode*>& nodes,
+                    bool                               inlude1stVertex=true,
+                    bool                               inludeLastVertex=true) const;
+
+  /*!
+   * \brief Return a node from the i-th VERTEX (count starts from zero)
+   *        Nodes moved to other geometry by MergeNodes() are also returned.
+   */
+  const SMDS_MeshNode* VertexNode(std::size_t i, bool* isMoved = 0) const;
 
   /*!
    * \brief Return edge and parameter on edge by normalized parameter
@@ -229,13 +246,17 @@ public:
    */
   const std::vector<TopoDS_Edge>& Edges() const { return myEdge; }
   /*!
-   * \brief Return 1st vertex of the i-the edge (count starts from zero)
+   * \brief Return 1st vertex of the i-th edge (count starts from zero)
    */
   TopoDS_Vertex FirstVertex(int i=0) const;
   /*!
-   * \brief Return last vertex of the i-the edge (count starts from zero)
+   * \brief Return last vertex of the i-th edge (count starts from zero)
    */
   TopoDS_Vertex LastVertex(int i=-1) const;
+  /*!
+   * \brief Return \c true if the chain of EDGEs is closed
+   */
+  bool IsClosed() const;
   /*!
    * \brief Return side length
    */
@@ -258,20 +279,20 @@ public:
    */
   inline Handle(Geom2d_Curve) Curve2d(int i) const;
   /*!
-   * \brief Return first normalized parameter of the i-the edge (count starts from zero)
+   * \brief Return first normalized parameter of the i-th edge (count starts from zero)
    */
   inline double FirstParameter(int i) const;
   /*!
-   * \brief Return last normalized parameter of the i-the edge (count starts from zero)
+   * \brief Return last normalized parameter of the i-th edge (count starts from zero)
    */
   inline double LastParameter(int i) const;
   /*!
-   * \brief Return first parameter of the i-the edge (count starts from zero).
+   * \brief Return first parameter of the i-th edge (count starts from zero).
    *        EDGE orientation is taken into account
    */
   inline double FirstU(int i) const;
   /*!
-   * \brief Return last parameter of the i-the edge (count starts from zero).
+   * \brief Return last parameter of the i-th edge (count starts from zero).
    *        EDGE orientation is taken into account
    */
   inline double LastU(int i) const;
@@ -289,6 +310,7 @@ protected:
   void reverseProxySubmesh( const TopoDS_Edge& E );
 
   // DON't FORGET to update Reverse() when adding one more vector!
+  TopoDS_Face                       myFace;
   std::vector<uvPtStruct>           myPoints, myFalsePoints;
   std::vector<TopoDS_Edge>          myEdge;
   std::vector<int>                  myEdgeID;
@@ -340,7 +362,7 @@ inline double StdMeshers_FaceSide::Parameter(double U, TopoDS_Edge & edge) const
 
 //================================================================================
 /*!
- * \brief Return first normalized parameter of the i-the edge
+ * \brief Return first normalized parameter of the i-th edge
  */
 //================================================================================
 
@@ -351,7 +373,7 @@ inline double StdMeshers_FaceSide::FirstParameter(int i) const
 
 //================================================================================
 /*!
- * \brief Return ast normalized parameter of the i-the edge
+ * \brief Return ast normalized parameter of the i-th edge
  */
 //================================================================================
 
@@ -362,7 +384,7 @@ inline double StdMeshers_FaceSide::LastParameter(int i) const
 
 //================================================================================
 /*!
- * \brief Return first parameter of the i-the edge
+ * \brief Return first parameter of the i-th edge
  */
 //================================================================================
 
@@ -373,7 +395,7 @@ inline double StdMeshers_FaceSide::FirstU(int i) const
 
 //================================================================================
 /*!
- * \brief Return last parameter of the i-the edge
+ * \brief Return last parameter of the i-th edge
  */
 //================================================================================
 

src/StdMeshers/StdMeshers_Projection_2D.cxx

@@ -441,32 +441,7 @@ namespace {
     tgtWires.resize( srcWires.size() );
     for ( size_t iW = 0; iW < srcWires.size(); ++iW )
     {
-      // check ori
-      //bool reverse = false;
       StdMeshers_FaceSidePtr srcWire = srcWires[iW];
-      // for ( int iE = 0; iE < srcWire->NbEdges(); ++iE )
-      // {
-      //   if ( srcHelper.IsRealSeam( srcWire->EdgeID( iE )))
-      //     continue;
-      //   TopoDS_Shape srcE = srcWire->Edge( iE );
-      //   TopoDS_Shape tgtE = shape2ShapeMap( srcE, /*isSrc=*/true);
-      //   if ( shape2ShapeMap._assocType == TShapeShapeMap::PROPAGATION ||
-      //        shape2ShapeMap._assocType == TShapeShapeMap::PROPAGATION)
-      //   {
-      //     reverse = false;
-      //   }
-      //   else if ( tgtMesh == srcMesh )
-      //   {
-      //     reverse = (( srcE.Orientation() == srcHelper.GetSubShapeOri( srcFace, srcE )) !=
-      //                ( tgtE.Orientation() == srcHelper.GetSubShapeOri( tgtFace, tgtE )));
-      //   }
-      //   else
-      //   {
-      //     TopoDS_Shape srcEbis = shape2ShapeMap( tgtE, /*isSrc=*/false );
-      //     reverse = ( srcE.Orientation() != srcEbis.Orientation() );
-      //   }
-      //   break;
-      // }
 
       list< TopoDS_Edge > tgtEdges;
       TopTools_IndexedMapOfShape edgeMap; // to detect seam edges
@@ -476,7 +451,6 @@ namespace {
         TopoDS_Edge     tgtE = TopoDS::Edge( shape2ShapeMap( srcE, /*isSrc=*/true));
         TopoDS_Shape srcEbis = shape2ShapeMap( tgtE, /*isSrc=*/false );
         if ( srcE.Orientation() != srcEbis.Orientation() )
-          //if ( reverse )
           tgtE.Reverse();
         // reverse a seam edge encountered for the second time
         const int index = edgeMap.Add( tgtE );
@@ -504,56 +478,58 @@ namespace {
             tgtE = nE.second;
         }
         tgtEdges.push_back( tgtE );
+      }
 
+      tgtWires[ iW ].reset( new StdMeshers_FaceSide( tgtFace, tgtEdges, tgtMesh,
+                                                     /*theIsForward = */ true,
+                                                     /*theIgnoreMediumNodes = */false));
+      StdMeshers_FaceSidePtr tgtWire = tgtWires[ iW ];
 
       // Fill map of src to tgt nodes with nodes on edges
 
-        if ( srcMesh->GetSubMesh( srcE )->IsEmpty() ||
+      for ( int iE = 0; iE < srcWire->NbEdges(); ++iE )
-             tgtMesh->GetSubMesh( tgtE )->IsEmpty() )
+      {
+        if ( srcMesh->GetSubMesh( srcWire->Edge(iE) )->IsEmpty() ||
+             tgtMesh->GetSubMesh( tgtWire->Edge(iE) )->IsEmpty() )
         {
           // add nodes on VERTEXes for a case of not meshes EDGEs
-          const TopoDS_Shape&  srcV = SMESH_MesherHelper::IthVertex( 0, srcE );
+          const SMDS_MeshNode* srcN = srcWire->VertexNode( iE );
-          const TopoDS_Shape&  tgtV = shape2ShapeMap( srcV, /*isSrc=*/true );
+          const SMDS_MeshNode* tgtN = tgtWire->VertexNode( iE );
-          const SMDS_MeshNode* srcN = SMESH_Algo::VertexNode( TopoDS::Vertex( srcV ), srcMeshDS );
-          const SMDS_MeshNode* tgtN = SMESH_Algo::VertexNode( TopoDS::Vertex( tgtV ), tgtMeshDS );
           if ( srcN && tgtN )
             src2tgtNodes.insert( make_pair( srcN, tgtN ));
         }
         else
         {
-          const bool skipMediumNodes = true;
+          const bool skipMedium = true, isFwd = true;
-          map< double, const SMDS_MeshNode* > srcNodes, tgtNodes;
+          StdMeshers_FaceSide srcEdge( srcFace, srcWire->Edge(iE), srcMesh, isFwd, skipMedium);
-          if ( !SMESH_Algo::GetSortedNodesOnEdge( srcMeshDS, srcE, skipMediumNodes, srcNodes) ||
+          StdMeshers_FaceSide tgtEdge( tgtFace, tgtWire->Edge(iE), tgtMesh, isFwd, skipMedium);
-               !SMESH_Algo::GetSortedNodesOnEdge( tgtMeshDS, tgtE, skipMediumNodes, tgtNodes ))
+          
-            return SMESH_ComputeError::New( COMPERR_BAD_INPUT_MESH,
+          vector< const SMDS_MeshNode* > srcNodes = srcEdge.GetOrderedNodes();
-                                            "Invalid node parameters on edges");
+          vector< const SMDS_MeshNode* > tgtNodes = tgtEdge.GetOrderedNodes();
 
           if (( srcNodes.size() != tgtNodes.size() ) && tgtNodes.size() > 0 )
             return SMESH_ComputeError::New( COMPERR_BAD_INPUT_MESH,
                                             "Different number of nodes on edges");
           if ( !tgtNodes.empty() )
           {
-            map< double, const SMDS_MeshNode* >::iterator u_tn = tgtNodes.begin();
+            vector< const SMDS_MeshNode* >::iterator tn = tgtNodes.begin();
-            if ( srcE.Orientation() == tgtE.Orientation() )
+            if ( srcWire->Edge(iE).Orientation() == tgtWire->Edge(iE).Orientation() )
             {
-              map< double, const SMDS_MeshNode* >::iterator u_sn = srcNodes.begin();
+              vector< const SMDS_MeshNode* >::iterator sn = srcNodes.begin();
-              for ( ; u_tn != tgtNodes.end(); ++u_tn, ++u_sn)
+              for ( ; tn != tgtNodes.end(); ++tn, ++sn)
-                src2tgtNodes.insert( make_pair( u_sn->second, u_tn->second ));
+                src2tgtNodes.insert( make_pair( *sn, *tn ));
             }
             else
             {
-              map< double, const SMDS_MeshNode* >::reverse_iterator u_sn = srcNodes.rbegin();
+              vector< const SMDS_MeshNode* >::reverse_iterator sn = srcNodes.rbegin();
-              for ( ; u_tn != tgtNodes.end(); ++u_tn, ++u_sn)
+              for ( ; tn != tgtNodes.end(); ++tn, ++sn)
-                src2tgtNodes.insert( make_pair( u_sn->second, u_tn->second ));
+                src2tgtNodes.insert( make_pair( *sn, *tn ));
             }
             is1DComputed = true;
           }
         }
       } // loop on EDGEs of a WIRE
 
-      tgtWires[ iW ].reset( new StdMeshers_FaceSide( tgtFace, tgtEdges, tgtMesh,
-                                                     /*theIsForward = */ true,
-                                                     /*theIgnoreMediumNodes = */false));
     } // loop on WIREs
 
     return TError();
@@ -670,7 +646,7 @@ namespace {
     // Make new faces
 
     // prepare the helper to adding quadratic elements if necessary
-    helper.SetSubShape( tgtFace );
+    //helper.SetSubShape( tgtFace );
     helper.IsQuadraticSubMesh( tgtFace );
 
     SMESHDS_SubMesh* srcSubDS = srcMeshDS->MeshElements( srcFace );

src/StdMeshers/StdMeshers_Quadrangle_2D.cxx

@@ -667,7 +667,7 @@ bool StdMeshers_Quadrangle_2D::computeQuadDominant(SMESH_Mesh&         aMesh,
       for ( ; i > stop; i--) {
         a = uv_e2[i].node;
         b = uv_e2[i - 1].node;
-        gp_Pnt pb (b->X(), b->Y(), b->Z());
+        gp_Pnt pb = SMESH_TNodeXYZ( b );
 
         // find node c in the grid, which will be linked with node b
         int near = g;
@@ -683,7 +683,7 @@ bool StdMeshers_Quadrangle_2D::computeQuadDominant(SMESH_Mesh&         aMesh,
               nk = uv_e1[nbright - 2].node;
             else
               nk = quad->uv_grid[nbhoriz*(nbvertic - 2) + k].node;
-            gp_Pnt pnk (nk->X(), nk->Y(), nk->Z());
+            gp_Pnt pnk = SMESH_TNodeXYZ( nk );
             double dist = pb.Distance(pnk);
             if (dist < mind - eps) {
               c = nk;
@@ -4227,6 +4227,7 @@ int StdMeshers_Quadrangle_2D::getCorners(const TopoDS_Face&          theFace,
   theNbDegenEdges = 0;
 
   SMESH_MesherHelper helper( theMesh );
+  StdMeshers_FaceSide faceSide( theFace, theWire, &theMesh, /*isFwd=*/true, /*skipMedium=*/true);
 
   // sort theVertices by angle
   multimap<double, TopoDS_Vertex> vertexByAngle;
@@ -4242,16 +4243,16 @@ int StdMeshers_Quadrangle_2D::getCorners(const TopoDS_Face&          theFace,
     prevE = *edge;
   }
   list<TopoDS_Edge>::iterator edge = theWire.begin();
-  for ( ; edge != theWire.end(); ++edge )
+  for ( int iE = 0; edge != theWire.end(); ++edge, ++iE )
   {
     if ( SMESH_Algo::isDegenerated( *edge ))
     {
       ++theNbDegenEdges;
       continue;
     }
-    TopoDS_Vertex v = helper.IthVertex( 0, *edge );
+    if ( !theConsiderMesh || faceSide.VertexNode( iE ))
-    if ( !theConsiderMesh || SMESH_Algo::VertexNode( v, helper.GetMeshDS() ))
     {
+      TopoDS_Vertex v = helper.IthVertex( 0, *edge );
       double    angle = SMESH_MesherHelper::GetAngle( prevE, *edge, theFace, v );
       vertexByAngle.insert( make_pair( angle, v ));
       angleByVertex.Bind( v, angle );
@@ -4271,6 +4272,14 @@ int StdMeshers_Quadrangle_2D::getCorners(const TopoDS_Face&          theFace,
     triaVertex.Nullify();
 
   // check nb of available corners
+  if ( faceSide.NbEdges() < nbCorners )
+    return error(COMPERR_BAD_SHAPE,
+                 TComm("Face must have 4 sides but not ") << faceSide.NbEdges() );
+
+  const int nbSegments = Max( faceSide.NbPoints()-1, faceSide.NbSegments() );
+  if ( nbSegments < nbCorners )
+    return error(COMPERR_BAD_INPUT_MESH, TComm("Too few boundary nodes: ") << nbSegments);
+
   if ( nbCorners == 3 )
   {
     if ( vertexByAngle.size() < 3 )