bool NETGENPlugin_Mesher::fillNgMesh(netgen::OCCGeometry&           occgeom,
                                     netgen::Mesh&                  ngMesh,
                                     vector<SMDS_MeshNode*>&        nodeVec,
                                     const list< SMESH_subMesh* > & meshedSM)
{
  TNode2IdMap nodeNgIdMap;

  TopTools_MapOfShape visitedShapes;

  SMESH_MesherHelper helper (*_mesh);

  int faceID = occgeom.fmap.Extent();
  _faceDescriptors.clear();

  list< SMESH_subMesh* >::const_iterator smIt, smEnd = meshedSM.end();
  for ( smIt = meshedSM.begin(); smIt != smEnd; ++smIt )
  {
    SMESH_subMesh* sm = *smIt;
    if ( !visitedShapes.Add( sm->GetSubShape() ))
      continue;

    SMESHDS_SubMesh * smDS = sm->GetSubMeshDS();

    switch ( sm->GetSubShape().ShapeType() )
    {
    case TopAbs_EDGE: { // EDGE
      // ----------------------
      const TopoDS_Edge& geomEdge  = TopoDS::Edge( sm->GetSubShape() );

      // Add ng segments for each not meshed face the edge bounds
      TopTools_MapOfShape visitedAncestors;
      const TopTools_ListOfShape& ancestors = _mesh->GetAncestors( geomEdge );
      TopTools_ListIteratorOfListOfShape ancestorIt ( ancestors );
      for ( ; ancestorIt.More(); ancestorIt.Next() )
      {
        const TopoDS_Shape & ans = ancestorIt.Value();
        if ( ans.ShapeType() != TopAbs_FACE || !visitedAncestors.Add( ans ))
          continue;
        const TopoDS_Face& face = TopoDS::Face( ans );

        int faceID = occgeom.fmap.FindIndex( face );
        if ( faceID < 1 )
          continue; // meshed face

        // find out orientation of geomEdge within face
        bool isForwad = false;
        for ( TopExp_Explorer exp( face, TopAbs_EDGE ); exp.More(); exp.Next() ) {
          if ( geomEdge.IsSame( exp.Current() )) {
            isForwad = ( exp.Current().Orientation() == geomEdge.Orientation() );
            break;
          }
        }
        bool isQuad = smDS->GetElements()->next()->IsQuadratic();

        // get all nodes from geomEdge
        StdMeshers_FaceSide fSide( face, geomEdge, _mesh, isForwad, isQuad );
        const vector<UVPtStruct>& points = fSide.GetUVPtStruct();
        int i, nbSeg = fSide.NbSegments();

        double otherSeamParam = 0;
        helper.SetSubShape( face );
        bool isSeam = helper.IsRealSeam( geomEdge );
        if ( isSeam )
          otherSeamParam =
            helper.GetOtherParam( helper.GetPeriodicIndex() == 1 ? points[0].u : points[0].v );

        // add segments

        int prevNgId = ngNodeId( points[0].node, ngMesh, nodeNgIdMap );

        for ( i = 0; i < nbSeg; ++i )
        {
          const UVPtStruct& p1 = points[ i ];
          const UVPtStruct& p2 = points[ i+1 ];

          netgen::Segment seg;
          // ng node ids
          seg.p1 = prevNgId;
          seg.p2 = prevNgId = ngNodeId( p2.node, ngMesh, nodeNgIdMap );
          // node param on curve
          seg.epgeominfo[ 0 ].dist = p1.param;
          seg.epgeominfo[ 1 ].dist = p2.param;
          // uv on face
          seg.epgeominfo[ 0 ].u = p1.u;
          seg.epgeominfo[ 0 ].v = p1.v;
          seg.epgeominfo[ 1 ].u = p2.u;
          seg.epgeominfo[ 1 ].v = p2.v;

          //seg.epgeominfo[ iEnd ].edgenr = edgeID; //  = geom.emap.FindIndex(edge);
          seg.si = faceID;                   // = geom.fmap.FindIndex (face);
          seg.edgenr = ngMesh.GetNSeg() + 1; // segment id
          ngMesh.AddSegment (seg);

          if ( isSeam )
          {
            if ( helper.GetPeriodicIndex() == 1 ) {
              seg.epgeominfo[ 0 ].u = otherSeamParam;
              seg.epgeominfo[ 1 ].u = otherSeamParam;
              swap (seg.epgeominfo[0].v, seg.epgeominfo[1].v);
            } else {
              seg.epgeominfo[ 0 ].v = otherSeamParam;
              seg.epgeominfo[ 1 ].v = otherSeamParam;
              swap (seg.epgeominfo[0].u, seg.epgeominfo[1].u);
            }
            swap (seg.p1, seg.p2);
            swap (seg.epgeominfo[0].dist, seg.epgeominfo[1].dist);
            seg.edgenr = ngMesh.GetNSeg() + 1; // segment id
            ngMesh.AddSegment (seg);
          }
        }
      } // loop on geomEdge ancestors

      break;
    } // case TopAbs_EDGE

    case TopAbs_FACE: { // FACE
      // ----------------------
      const TopoDS_Face& geomFace  = TopoDS::Face( sm->GetSubShape() );
      helper.SetSubShape( geomFace );

      // Find solids the geomFace bounds
      int solidID1 = 0, solidID2 = 0;
      const TopTools_ListOfShape& ancestors = _mesh->GetAncestors( geomFace );
      TopTools_ListIteratorOfListOfShape ancestorIt ( ancestors );
      for ( ; ancestorIt.More(); ancestorIt.Next() )
      {
        const TopoDS_Shape & solid = ancestorIt.Value();
        if ( solid.ShapeType() == TopAbs_SOLID  ) {
          int id = occgeom.somap.FindIndex ( solid );
          if ( solidID1 && id != solidID1 ) solidID2 = id;
          else                              solidID1 = id;
        }
      }
      faceID++;
      _faceDescriptors[ faceID ].first  = solidID1;
      _faceDescriptors[ faceID ].second = solidID2;

      // Orient the face correctly in solidID1 (issue 0020206)
      bool reverse = false;
      if ( solidID1 ) {
        TopoDS_Shape solid = occgeom.somap( solidID1 );
        for ( TopExp_Explorer f( solid, TopAbs_FACE ); f.More(); f.Next() ) {
          if ( geomFace.IsSame( f.Current() )) {
            reverse = SMESH_Algo::IsReversedSubMesh( TopoDS::Face( f.Current()), helper.GetMeshDS() );
            break;
          }
        }
      }

      // Add surface elements
      SMDS_ElemIteratorPtr faces = smDS->GetElements();
      while ( faces->more() ) {

        const SMDS_MeshElement* f = faces->next();
        if ( f->NbNodes() % 3 != 0 ) { // not triangle
          for ( ancestorIt.Initialize(ancestors); ancestorIt.More(); ancestorIt.Next() )
            if ( ancestorIt.Value().ShapeType() == TopAbs_SOLID  ) {
              sm = _mesh->GetSubMesh( ancestorIt.Value() );
              break;
            }
          SMESH_ComputeErrorPtr& smError = sm->GetComputeError();
          smError.reset( new SMESH_ComputeError(COMPERR_BAD_INPUT_MESH,"Not triangle submesh"));
          smError->myBadElements.push_back( f );
          return false;
        }

        netgen::Element2d tri(3);
        tri.SetIndex ( faceID );

        for ( int i = 0; i < 3; ++i ) {
          const SMDS_MeshNode* node = f->GetNode( i ), * inFaceNode=0;
          if ( helper.IsSeamShape( node->GetPosition()->GetShapeId() ))
            if ( helper.IsSeamShape( f->GetNodeWrap( i+1 )->GetPosition()->GetShapeId() ))
              inFaceNode = f->GetNodeWrap( i-1 );
            else 
              inFaceNode = f->GetNodeWrap( i+1 );

          gp_XY uv = helper.GetNodeUV( geomFace, node, inFaceNode );
          if ( reverse ) {
            tri.GeomInfoPi(3-i).u = uv.X();
            tri.GeomInfoPi(3-i).v = uv.Y();
            tri.PNum      (3-i) = ngNodeId( node, ngMesh, nodeNgIdMap );
          } else {
            tri.GeomInfoPi(i+1).u = uv.X();
            tri.GeomInfoPi(i+1).v = uv.Y();
            tri.PNum      (i+1) = ngNodeId( node, ngMesh, nodeNgIdMap );
          }
        }

        ngMesh.AddSurfaceElement (tri);

      }
      break;
    } //

    case TopAbs_VERTEX: { // VERTEX
      // --------------------------
      SMDS_NodeIteratorPtr nodeIt = smDS->GetNodes();
      if ( nodeIt->more() )
        ngNodeId( nodeIt->next(), ngMesh, nodeNgIdMap );
      break;
    }
    default:;
    } // switch
  } // loop on submeshes

  // fill nodeVec
  nodeVec.resize( ngMesh.GetNP() + 1 );
  TNode2IdMap::iterator node_NgId, nodeNgIdEnd = nodeNgIdMap.end();
  for ( node_NgId = nodeNgIdMap.begin(); node_NgId != nodeNgIdEnd; ++node_NgId)
    nodeVec[ node_NgId->second ] = (SMDS_MeshNode*) node_NgId->first;

  return true;
}
Exemplo n.º 2
0
bool NETGENPlugin_NETGEN_3D::Compute(SMESH_Mesh&         aMesh,
                                     const TopoDS_Shape& aShape)
{
    MESSAGE("NETGENPlugin_NETGEN_3D::Compute with maxElmentsize = " << _maxElementVolume);

    SMESHDS_Mesh* meshDS = aMesh.GetMeshDS();

    const int invalid_ID = -1;

    SMESH::Controls::Area areaControl;
    SMESH::Controls::TSequenceOfXYZ nodesCoords;

    // -------------------------------------------------------------------
    // get triangles on aShell and make a map of nodes to Netgen node IDs
    // -------------------------------------------------------------------

    SMESH_MesherHelper helper(aMesh);
    SMESH_MesherHelper* myTool = &helper;
    bool _quadraticMesh = myTool->IsQuadraticSubMesh(aShape);

    typedef map< const SMDS_MeshNode*, int, TIDCompare > TNodeToIDMap;
    TNodeToIDMap nodeToNetgenID;
    list< const SMDS_MeshElement* > triangles;
    list< bool >                    isReversed; // orientation of triangles

    TopAbs_ShapeEnum mainType = aMesh.GetShapeToMesh().ShapeType();
    bool checkReverse = ( mainType == TopAbs_COMPOUND || mainType == TopAbs_COMPSOLID );

    // for the degeneraged edge: ignore all but one node on it;
    // map storing ids of degen edges and vertices and their netgen id:
    map< int, int* > degenShapeIdToPtrNgId;
    map< int, int* >::iterator shId_ngId;
    list< int > degenNgIds;

    StdMeshers_QuadToTriaAdaptor Adaptor;
    Adaptor.Compute(aMesh,aShape);

    for (TopExp_Explorer exp(aShape,TopAbs_FACE); exp.More(); exp.Next())
    {
        const TopoDS_Shape& aShapeFace = exp.Current();
        const SMESHDS_SubMesh * aSubMeshDSFace = meshDS->MeshElements( aShapeFace );
        if ( aSubMeshDSFace )
        {
            bool isRev = false;
            if ( checkReverse && helper.NbAncestors(aShapeFace, aMesh, aShape.ShapeType()) > 1 )
                // IsReversedSubMesh() can work wrong on strongly curved faces,
                // so we use it as less as possible
                isRev = SMESH_Algo::IsReversedSubMesh( TopoDS::Face(aShapeFace), meshDS );

            SMDS_ElemIteratorPtr iteratorElem = aSubMeshDSFace->GetElements();
            while ( iteratorElem->more() ) // loop on elements on a face
            {
                // check element
                const SMDS_MeshElement* elem = iteratorElem->next();
                if ( !elem )
                    return error( COMPERR_BAD_INPUT_MESH, "Null element encounters");
                bool isTraingle = ( elem->NbNodes()==3 || (_quadraticMesh && elem->NbNodes()==6 ));
                if ( !isTraingle ) {
                    //return error( COMPERR_BAD_INPUT_MESH,
                    //              SMESH_Comment("Not triangle element ")<<elem->GetID());
                    // using adaptor
                    const list<const SMDS_FaceOfNodes*>* faces = Adaptor.GetTriangles(elem);
                    if(faces==0) {
                        return error( COMPERR_BAD_INPUT_MESH,
                                      SMESH_Comment("Not triangles in adaptor for element ")<<elem->GetID());
                    }
                    list<const SMDS_FaceOfNodes*>::const_iterator itf = faces->begin();
                    for(; itf!=faces->end(); itf++ ) {
                        triangles.push_back( (*itf) );
                        isReversed.push_back( isRev );
                        // put triange's nodes to nodeToNetgenID map
                        SMDS_ElemIteratorPtr triangleNodesIt = (*itf)->nodesIterator();
                        while ( triangleNodesIt->more() ) {
                            const SMDS_MeshNode * node =
                                static_cast<const SMDS_MeshNode *>(triangleNodesIt->next());
                            if(myTool->IsMedium(node))
                                continue;
                            nodeToNetgenID.insert( make_pair( node, invalid_ID ));
                        }
                    }
                }
                else {
                    // keep a triangle
                    triangles.push_back( elem );
                    isReversed.push_back( isRev );
                    // put elem nodes to nodeToNetgenID map
                    SMDS_ElemIteratorPtr triangleNodesIt = elem->nodesIterator();
                    while ( triangleNodesIt->more() ) {
                        const SMDS_MeshNode * node =
                            static_cast<const SMDS_MeshNode *>(triangleNodesIt->next());
                        if(myTool->IsMedium(node))
                            continue;
                        nodeToNetgenID.insert( make_pair( node, invalid_ID ));
                    }
                }
#ifdef _DEBUG_
                // check if a trainge is degenerated
                areaControl.GetPoints( elem, nodesCoords );
                double area = areaControl.GetValue( nodesCoords );
                if ( area <= DBL_MIN ) {
                    MESSAGE( "Warning: Degenerated " << elem );
                }
#endif
            }
            // look for degeneraged edges and vetices
            for (TopExp_Explorer expE(aShapeFace,TopAbs_EDGE); expE.More(); expE.Next())
            {
                TopoDS_Edge aShapeEdge = TopoDS::Edge( expE.Current() );
                if ( BRep_Tool::Degenerated( aShapeEdge ))
                {
                    degenNgIds.push_back( invalid_ID );
                    int* ptrIdOnEdge = & degenNgIds.back();
                    // remember edge id
                    int edgeID = meshDS->ShapeToIndex( aShapeEdge );
                    degenShapeIdToPtrNgId.insert( make_pair( edgeID, ptrIdOnEdge ));
                    // remember vertex id
                    int vertexID = meshDS->ShapeToIndex( TopExp::FirstVertex( aShapeEdge ));
                    degenShapeIdToPtrNgId.insert( make_pair( vertexID, ptrIdOnEdge ));
                }
            }
        }
    }
    // ---------------------------------
    // Feed the Netgen with surface mesh
    // ---------------------------------

    int Netgen_NbOfNodes = 0;
    int Netgen_param2ndOrder = 0;
    double Netgen_paramFine = 1.;
    double Netgen_paramSize = pow( 72, 1/6. ) * pow( _maxElementVolume, 1/3. );

    double Netgen_point[3];
    int Netgen_triangle[3];
    int Netgen_tetrahedron[4];

    Ng_Init();

    Ng_Mesh * Netgen_mesh = Ng_NewMesh();

    // set nodes and remember thier netgen IDs
    bool isDegen = false, hasDegen = !degenShapeIdToPtrNgId.empty();
    TNodeToIDMap::iterator n_id = nodeToNetgenID.begin();
    for ( ; n_id != nodeToNetgenID.end(); ++n_id )
    {
        const SMDS_MeshNode* node = n_id->first;

        // ignore nodes on degenerated edge
        if ( hasDegen ) {
            int shapeId = node->GetPosition()->GetShapeId();
            shId_ngId = degenShapeIdToPtrNgId.find( shapeId );
            isDegen = ( shId_ngId != degenShapeIdToPtrNgId.end() );
            if ( isDegen && *(shId_ngId->second) != invalid_ID ) {
                n_id->second = *(shId_ngId->second);
                continue;
            }
        }
        Netgen_point [ 0 ] = node->X();
        Netgen_point [ 1 ] = node->Y();
        Netgen_point [ 2 ] = node->Z();
        Ng_AddPoint(Netgen_mesh, Netgen_point);
        n_id->second = ++Netgen_NbOfNodes; // set netgen ID

        if ( isDegen ) // all nodes on a degen edge get one netgen ID
            *(shId_ngId->second) = n_id->second;
    }

    // set triangles
    list< const SMDS_MeshElement* >::iterator tria = triangles.begin();
    list< bool >::iterator                 reverse = isReversed.begin();
    for ( ; tria != triangles.end(); ++tria, ++reverse )
    {
        int i = 0;
        SMDS_ElemIteratorPtr triangleNodesIt = (*tria)->nodesIterator();
        while ( triangleNodesIt->more() ) {
            const SMDS_MeshNode * node =
                static_cast<const SMDS_MeshNode *>(triangleNodesIt->next());
            if(myTool->IsMedium(node))
                continue;
            Netgen_triangle[ *reverse ? 2 - i : i ] = nodeToNetgenID[ node ];
            ++i;
        }
        if ( !hasDegen ||
                // ignore degenerated triangles, they have 2 or 3 same ids
                (Netgen_triangle[0] != Netgen_triangle[1] &&
                 Netgen_triangle[0] != Netgen_triangle[2] &&
                 Netgen_triangle[2] != Netgen_triangle[1] ))
        {
            Ng_AddSurfaceElement(Netgen_mesh, NG_TRIG, Netgen_triangle);
        }
    }

    // -------------------------
    // Generate the volume mesh
    // -------------------------

    Ng_Meshing_Parameters Netgen_param;

    Netgen_param.secondorder = Netgen_param2ndOrder;
    Netgen_param.fineness = Netgen_paramFine;
    Netgen_param.maxh = Netgen_paramSize;

    Ng_Result status;

    try {
#if (OCC_VERSION_MAJOR << 16 | OCC_VERSION_MINOR << 8 | OCC_VERSION_MAINTENANCE) > 0x060100
        OCC_CATCH_SIGNALS;
#endif
        status = Ng_GenerateVolumeMesh(Netgen_mesh, &Netgen_param);
    }
    catch (Standard_Failure& exc) {
        error(COMPERR_OCC_EXCEPTION, exc.GetMessageString());
        status = NG_VOLUME_FAILURE;
    }
    catch (...) {
        error("Exception in Ng_GenerateVolumeMesh()");
        status = NG_VOLUME_FAILURE;
    }
    if ( GetComputeError()->IsOK() ) {
        switch ( status ) {
        case NG_SURFACE_INPUT_ERROR:
            error( status, "NG_SURFACE_INPUT_ERROR");
        case NG_VOLUME_FAILURE:
            error( status, "NG_VOLUME_FAILURE");
        case NG_STL_INPUT_ERROR:
            error( status, "NG_STL_INPUT_ERROR");
        case NG_SURFACE_FAILURE:
            error( status, "NG_SURFACE_FAILURE");
        case NG_FILE_NOT_FOUND:
            error( status, "NG_FILE_NOT_FOUND");
        };
    }

    int Netgen_NbOfNodesNew = Ng_GetNP(Netgen_mesh);

    int Netgen_NbOfTetra = Ng_GetNE(Netgen_mesh);

    MESSAGE("End of Volume Mesh Generation. status=" << status <<
            ", nb new nodes: " << Netgen_NbOfNodesNew - Netgen_NbOfNodes <<
            ", nb tetra: " << Netgen_NbOfTetra);

    // -------------------------------------------------------------------
    // Feed back the SMESHDS with the generated Nodes and Volume Elements
    // -------------------------------------------------------------------

    bool isOK = ( /*status == NG_OK &&*/ Netgen_NbOfTetra > 0 );// get whatever built
    if ( isOK )
    {
        // vector of nodes in which node index == netgen ID
        vector< const SMDS_MeshNode* > nodeVec ( Netgen_NbOfNodesNew + 1 );
        // insert old nodes into nodeVec
        for ( n_id = nodeToNetgenID.begin(); n_id != nodeToNetgenID.end(); ++n_id ) {
            nodeVec.at( n_id->second ) = n_id->first;
        }
        // create and insert new nodes into nodeVec
        int nodeIndex = Netgen_NbOfNodes + 1;
        int shapeID = meshDS->ShapeToIndex( aShape );
        for ( ; nodeIndex <= Netgen_NbOfNodesNew; ++nodeIndex )
        {
            Ng_GetPoint( Netgen_mesh, nodeIndex, Netgen_point );
            SMDS_MeshNode * node = meshDS->AddNode(Netgen_point[0],
                                                   Netgen_point[1],
                                                   Netgen_point[2]);
            meshDS->SetNodeInVolume(node, shapeID);
            nodeVec.at(nodeIndex) = node;
        }

        // create tetrahedrons
        for ( int elemIndex = 1; elemIndex <= Netgen_NbOfTetra; ++elemIndex )
        {
            Ng_GetVolumeElement(Netgen_mesh, elemIndex, Netgen_tetrahedron);
            SMDS_MeshVolume * elt = myTool->AddVolume (nodeVec.at( Netgen_tetrahedron[0] ),
                                    nodeVec.at( Netgen_tetrahedron[1] ),
                                    nodeVec.at( Netgen_tetrahedron[2] ),
                                    nodeVec.at( Netgen_tetrahedron[3] ));
            meshDS->SetMeshElementOnShape(elt, shapeID );
        }
    }

    Ng_DeleteMesh(Netgen_mesh);
    Ng_Exit();

    NETGENPlugin_Mesher::RemoveTmpFiles();

    return (status == NG_OK);
}
static TError AddSegmentsToMesh(netgen::Mesh&                    ngMesh,
                                OCCGeometry&                     geom,
                                const TSideVector&               wires,
                                SMESH_MesherHelper&              helper,
                                vector< const SMDS_MeshNode* > & nodeVec)
{
  // ----------------------------
  // Check wires and count nodes
  // ----------------------------
  int nbNodes = 0;
  for ( int iW = 0; iW < wires.size(); ++iW )
  {
    StdMeshers_FaceSidePtr wire = wires[ iW ];
    if ( wire->MissVertexNode() )
      return TError
        (new SMESH_ComputeError(COMPERR_BAD_INPUT_MESH, "Missing nodes on vertices"));
      
    const vector<UVPtStruct>& uvPtVec = wire->GetUVPtStruct();
    if ( uvPtVec.size() != wire->NbPoints() )
      return TError
        (new SMESH_ComputeError(COMPERR_BAD_INPUT_MESH,
                                SMESH_Comment("Unexpected nb of points on wire ") << iW
                                << ": " << uvPtVec.size()<<" != "<<wire->NbPoints()));
    nbNodes += wire->NbSegments();
  }
  nodeVec.reserve( nbNodes );

  // -----------------
  // Fill netgen mesh
  // -----------------

//   netgen::Box<3> bb = geom.GetBoundingBox();
//   bb.Increase (bb.Diam()/10);
//   ngMesh.SetLocalH (bb.PMin(), bb.PMax(), 0.5); // set grading

  const int faceID = 1, solidID = 0;
  ngMesh.AddFaceDescriptor (FaceDescriptor(faceID, solidID, solidID, 0));

  for ( int iW = 0; iW < wires.size(); ++iW )
  {
    StdMeshers_FaceSidePtr wire = wires[ iW ];
    const vector<UVPtStruct>& uvPtVec = wire->GetUVPtStruct();

    int firstPointID = ngMesh.GetNP() + 1;
    int edgeID = 1, posID = -2;
    for ( int i = 0; i < wire->NbSegments(); ++i ) // loop on segments
    {
      // Add the first point of a segment
      const SMDS_MeshNode * n = uvPtVec[ i ].node;
      const int posShapeID = n->GetPosition()->GetShapeId();

      // skip nodes on degenerated edges
      if ( helper.IsDegenShape( posShapeID ) &&
           helper.IsDegenShape( uvPtVec[ i+1 ].node->GetPosition()->GetShapeId() ))
        continue;

      nodeVec.push_back( n );

      MeshPoint mp( Point<3> (n->X(), n->Y(), n->Z()) );
      ngMesh.AddPoint ( mp, 1, EDGEPOINT );

      // Add the segment
      Segment seg;

      seg.pnums[0] = ngMesh.GetNP();          // ng node id
      seg.pnums[1] = seg.pnums[0] + 1;              // ng node id
      seg.edgenr = ngMesh.GetNSeg() + 1;// segment id
      seg.si = faceID;                  // = geom.fmap.FindIndex (face);

      for ( int iEnd = 0; iEnd < 2; ++iEnd)
      {
        const UVPtStruct& pnt = uvPtVec[ i + iEnd ];

        seg.epgeominfo[ iEnd ].dist = pnt.param; // param on curve
        seg.epgeominfo[ iEnd ].u    = pnt.u;
        seg.epgeominfo[ iEnd ].v    = pnt.v;

        // find out edge id and node parameter on edge
        bool onVertex = ( pnt.node->GetPosition()->GetTypeOfPosition() == SMDS_TOP_VERTEX );
        if ( onVertex || posShapeID != posID )
        {
          // get edge id
          double normParam = pnt.normParam;
          if ( onVertex )
            normParam = 0.5 * ( uvPtVec[ i ].normParam + uvPtVec[ i+1 ].normParam );
          const TopoDS_Edge& edge = wire->Edge( wire->EdgeIndex( normParam ));
          edgeID = geom.emap.FindIndex( edge );
          posID  = posShapeID;
          if ( onVertex ) // param on curve is different on each of two edges
            seg.epgeominfo[ iEnd ].dist = helper.GetNodeU( edge, pnt.node );
        }
        seg.epgeominfo[ iEnd ].edgenr = edgeID; //  = geom.emap.FindIndex(edge);
      }

      ngMesh.AddSegment (seg);

//       cout << "Segment: " << seg.edgenr << endl
//            << "\tp1: " << seg.p1 << endl
//            << "\tp2: " << seg.p2 << endl
//            << "\tp0 param: " << seg.epgeominfo[ 0 ].dist << endl
//            << "\tp0 uv: " << seg.epgeominfo[ 0 ].u <<", "<< seg.epgeominfo[ 0 ].v << endl
//            << "\tp0 edge: " << seg.epgeominfo[ 0 ].edgenr << endl
//            << "\tp1 param: " << seg.epgeominfo[ 1 ].dist << endl
//            << "\tp1 uv: " << seg.epgeominfo[ 1 ].u <<", "<< seg.epgeominfo[ 1 ].v << endl
//            << "\tp1 edge: " << seg.epgeominfo[ 1 ].edgenr << endl;
    }
    Segment& seg = ngMesh.LineSegment( ngMesh.GetNSeg() );
    seg.pnums[1] = firstPointID;
  }

  ngMesh.CalcSurfacesOfNode();  

  return TError();
}
bool NETGENPlugin_NETGEN_3D::compute(SMESH_Mesh&                     aMesh,
                                     SMESH_MesherHelper&             helper,
                                     vector< const SMDS_MeshNode* >& nodeVec,
                                     Ng_Mesh *                       Netgen_mesh)
{
  netgen::multithread.terminate = 0;

  netgen::Mesh* ngMesh = (netgen::Mesh*)Netgen_mesh;
  int Netgen_NbOfNodes = Ng_GetNP(Netgen_mesh);

#if NETGEN_VERSION < 5
  char *optstr = 0;
#endif
  int startWith = netgen::MESHCONST_MESHVOLUME;
  int endWith   = netgen::MESHCONST_OPTVOLUME;
  int err = 1;

  NETGENPlugin_Mesher aMesher( &aMesh, helper.GetSubShape(), /*isVolume=*/true );
  netgen::OCCGeometry occgeo;
  
  if ( _hypParameters )
  {
    aMesher.SetParameters( _hypParameters );
    if ( !_hypParameters->GetOptimize() )
      endWith = netgen::MESHCONST_MESHVOLUME;
  }
  else if ( _hypMaxElementVolume )
  {
    netgen::mparam.maxh = pow( 72, 1/6. ) * pow( _maxElementVolume, 1/3. );
    // limitVolumeSize( ngMesh, netgen::mparam.maxh ); // result is unpredictable
  }
  else if ( aMesh.HasShapeToMesh() )
  {
    aMesher.PrepareOCCgeometry( occgeo, helper.GetSubShape(), aMesh );
    netgen::mparam.maxh = occgeo.GetBoundingBox().Diam()/2;
  }
  else
  {
    netgen::Point3d pmin, pmax;
    ngMesh->GetBox (pmin, pmax);
    netgen::mparam.maxh = Dist(pmin, pmax)/2;
  }

  if ( !_hypParameters && aMesh.HasShapeToMesh() )
  {
    netgen::mparam.minh = aMesher.GetDefaultMinSize( helper.GetSubShape(), netgen::mparam.maxh );
  }

  try
  {
    OCC_CATCH_SIGNALS;

#if NETGEN_VERSION > 4
    ngMesh->CalcLocalH(netgen::mparam.grading);
    err = netgen::OCCGenerateMesh(occgeo, ngMesh, netgen::mparam, startWith, endWith);
#else
    ngMesh->CalcLocalH();
    err = netgen::OCCGenerateMesh(occgeo, ngMesh, startWith, endWith, optstr);
#endif
    if(netgen::multithread.terminate)
      return false;
    if ( err )
      error(SMESH_Comment("Error in netgen::OCCGenerateMesh() at ") << netgen::multithread.task);
  }
  catch (Standard_Failure& ex)
  {
    SMESH_Comment str("Exception in  netgen::OCCGenerateMesh()");
    str << " at " << netgen::multithread.task
        << ": " << ex.DynamicType()->Name();
    if ( ex.GetMessageString() && strlen( ex.GetMessageString() ))
      str << ": " << ex.GetMessageString();
    error(str);
  }
  catch (netgen::NgException exc)
  {
    SMESH_Comment str("NgException");
    if ( strlen( netgen::multithread.task ) > 0 )
      str << " at " << netgen::multithread.task;
    str << ": " << exc.What();
    error(str);
  }
  catch (...)
  {
    SMESH_Comment str("Exception in  netgen::OCCGenerateMesh()");
    if ( strlen( netgen::multithread.task ) > 0 )
      str << " at " << netgen::multithread.task;
    error(str);
  }

  int Netgen_NbOfNodesNew = Ng_GetNP(Netgen_mesh);
  int Netgen_NbOfTetra    = Ng_GetNE(Netgen_mesh);

  MESSAGE("End of Volume Mesh Generation. err=" << err <<
          ", nb new nodes: " << Netgen_NbOfNodesNew - Netgen_NbOfNodes <<
          ", nb tetra: " << Netgen_NbOfTetra);

  // -------------------------------------------------------------------
  // Feed back the SMESHDS with the generated Nodes and Volume Elements
  // -------------------------------------------------------------------

  if ( err )
  {
    SMESH_ComputeErrorPtr ce = NETGENPlugin_Mesher::ReadErrors(nodeVec);
    if ( ce && !ce->myBadElements.empty() )
      error( ce );
  }

  bool isOK = ( /*status == NG_OK &&*/ Netgen_NbOfTetra > 0 );// get whatever built
  if ( isOK )
  {
    double Netgen_point[3];
    int    Netgen_tetrahedron[4];

    // create and insert new nodes into nodeVec
    nodeVec.resize( Netgen_NbOfNodesNew + 1, 0 );
    int nodeIndex = Netgen_NbOfNodes + 1;
    for ( ; nodeIndex <= Netgen_NbOfNodesNew; ++nodeIndex )
    {
      Ng_GetPoint( Netgen_mesh, nodeIndex, Netgen_point );
      nodeVec.at(nodeIndex) = helper.AddNode(Netgen_point[0], Netgen_point[1], Netgen_point[2]);
    }

    // create tetrahedrons
    for ( int elemIndex = 1; elemIndex <= Netgen_NbOfTetra; ++elemIndex )
    {
      Ng_GetVolumeElement(Netgen_mesh, elemIndex, Netgen_tetrahedron);
      try
      {
        helper.AddVolume (nodeVec.at( Netgen_tetrahedron[0] ),
                          nodeVec.at( Netgen_tetrahedron[1] ),
                          nodeVec.at( Netgen_tetrahedron[2] ),
                          nodeVec.at( Netgen_tetrahedron[3] ));
      }
      catch (...)
      {
      }
    }
  }

  return !err;
}
bool StdMeshers_Hexa_3D::Compute(SMESH_Mesh &         aMesh,
                                 const TopoDS_Shape & aShape)// throw(SALOME_Exception)
{
  // PAL14921. Enable catching std::bad_alloc and Standard_OutOfMemory outside
  //Unexpect aCatch(SalomeException);
  MESSAGE("StdMeshers_Hexa_3D::Compute");
  SMESHDS_Mesh * meshDS = aMesh.GetMeshDS();

  // 0.  - shape and face mesh verification
  // 0.1 - shape must be a solid (or a shell) with 6 faces

  vector < SMESH_subMesh * >meshFaces;
  for (TopExp_Explorer exp(aShape, TopAbs_FACE); exp.More(); exp.Next()) {
    SMESH_subMesh *aSubMesh = aMesh.GetSubMeshContaining(exp.Current());
    ASSERT(aSubMesh);
    meshFaces.push_back(aSubMesh);
  }
  if (meshFaces.size() != 6) {
    //return error(COMPERR_BAD_SHAPE, TComm(meshFaces.size())<<" instead of 6 faces in a block");
    static StdMeshers_CompositeHexa_3D compositeHexa(-10, 0, aMesh.GetGen());
    if ( !compositeHexa.Compute( aMesh, aShape ))
      return error( compositeHexa.GetComputeError() );
    return true;
  }

  // 0.2 - is each face meshed with Quadrangle_2D? (so, with a wire of 4 edges)

  // tool for working with quadratic elements
  SMESH_MesherHelper aTool (aMesh);
  _quadraticMesh = aTool.IsQuadraticSubMesh(aShape);

  // cube structure
  typedef struct cubeStruct
  {
    TopoDS_Vertex V000;
    TopoDS_Vertex V001;
    TopoDS_Vertex V010;
    TopoDS_Vertex V011;
    TopoDS_Vertex V100;
    TopoDS_Vertex V101;
    TopoDS_Vertex V110;
    TopoDS_Vertex V111;
    faceQuadStruct* quad_X0;
    faceQuadStruct* quad_X1;
    faceQuadStruct* quad_Y0;
    faceQuadStruct* quad_Y1;
    faceQuadStruct* quad_Z0;
    faceQuadStruct* quad_Z1;
    Point3DStruct* np; // normalised 3D coordinates
  } CubeStruct;

  CubeStruct aCube;

  // bounding faces
  FaceQuadStruct* aQuads[6];
  for (int i = 0; i < 6; i++)
    aQuads[i] = 0;

  for (int i = 0; i < 6; i++)
  {
    TopoDS_Shape aFace = meshFaces[i]->GetSubShape();
    SMESH_Algo *algo = _gen->GetAlgo(aMesh, aFace);
    string algoName = algo->GetName();
    bool isAllQuad = false;
    if (algoName == "Quadrangle_2D") {
      SMESHDS_SubMesh * sm = meshDS->MeshElements( aFace );
      if ( sm ) {
        isAllQuad = true;
        SMDS_ElemIteratorPtr eIt = sm->GetElements();
        while ( isAllQuad && eIt->more() ) {
          const SMDS_MeshElement* elem =  eIt->next();
          isAllQuad = ( elem->NbNodes()==4 ||(_quadraticMesh && elem->NbNodes()==8) );
        }
      }
    }
    if ( ! isAllQuad ) {
      SMESH_ComputeErrorPtr err = ComputePentahedralMesh(aMesh, aShape);
      return ClearAndReturn( aQuads, error(err));
    }
    StdMeshers_Quadrangle_2D *quadAlgo =
      dynamic_cast < StdMeshers_Quadrangle_2D * >(algo);
    ASSERT(quadAlgo);
    try {
      aQuads[i] = quadAlgo->CheckAnd2Dcompute(aMesh, aFace, _quadraticMesh);
      if(!aQuads[i]) {
        return error( quadAlgo->GetComputeError());
      }
    }
    catch(SALOME_Exception & S_ex) {
      return ClearAndReturn( aQuads, error(COMPERR_SLM_EXCEPTION,TComm(S_ex.what()) <<
                                           " Raised by StdMeshers_Quadrangle_2D "
                                           " on face #" << meshDS->ShapeToIndex( aFace )));
    }

    // 0.2.1 - number of points on the opposite edges must be the same
    if (aQuads[i]->side[0]->NbPoints() != aQuads[i]->side[2]->NbPoints() ||
        aQuads[i]->side[1]->NbPoints() != aQuads[i]->side[3]->NbPoints()
        /*aQuads[i]->side[0]->NbEdges() != 1 ||
        aQuads[i]->side[1]->NbEdges() != 1 ||
        aQuads[i]->side[2]->NbEdges() != 1 ||
        aQuads[i]->side[3]->NbEdges() != 1*/) {
      MESSAGE("different number of points on the opposite edges of face " << i);
      // Try to go into penta algorithm 'cause it has been improved.
      SMESH_ComputeErrorPtr err = ComputePentahedralMesh(aMesh, aShape);
      return ClearAndReturn( aQuads, error(err));
    }
  }

  // 1.  - identify faces and vertices of the "cube"
  // 1.1 - ancestor maps vertex->edges in the cube

//   TopTools_IndexedDataMapOfShapeListOfShape MS;
//   TopExp::MapShapesAndAncestors(aShape, TopAbs_VERTEX, TopAbs_EDGE, MS);

  // 1.2 - first face is choosen as face Y=0 of the unit cube

  const TopoDS_Shape & aFace = meshFaces[0]->GetSubShape();
  //const TopoDS_Face & F = TopoDS::Face(aFace);

  // 1.3 - identify the 4 vertices of the face Y=0: V000, V100, V101, V001

  aCube.V000 = aQuads[0]->side[0]->FirstVertex(); // will be (0,0,0) on the unit cube
  aCube.V100 = aQuads[0]->side[0]->LastVertex();  // will be (1,0,0) on the unit cube
  aCube.V001 = aQuads[0]->side[2]->FirstVertex(); // will be (0,0,1) on the unit cube
  aCube.V101 = aQuads[0]->side[2]->LastVertex();  // will be (1,0,1) on the unit cube

  TopTools_IndexedMapOfShape MV0;
  TopExp::MapShapes(aFace, TopAbs_VERTEX, MV0);

  aCube.V010 = OppositeVertex( aCube.V000, MV0, aQuads);
  aCube.V110 = OppositeVertex( aCube.V100, MV0, aQuads);
  aCube.V011 = OppositeVertex( aCube.V001, MV0, aQuads);
  aCube.V111 = OppositeVertex( aCube.V101, MV0, aQuads);

  // 1.6 - find remaining faces given 4 vertices

  int _indY0 = 0;
  int _indY1 = GetFaceIndex(aMesh, aShape, meshFaces,
                            aCube.V010, aCube.V011, aCube.V110, aCube.V111);
  int _indZ0 = GetFaceIndex(aMesh, aShape, meshFaces,
                            aCube.V000, aCube.V010, aCube.V100, aCube.V110);
  int _indZ1 = GetFaceIndex(aMesh, aShape, meshFaces,
                            aCube.V001, aCube.V011, aCube.V101, aCube.V111);
  int _indX0 = GetFaceIndex(aMesh, aShape, meshFaces,
                            aCube.V000, aCube.V001, aCube.V010, aCube.V011);
  int _indX1 = GetFaceIndex(aMesh, aShape, meshFaces,
                            aCube.V100, aCube.V101, aCube.V110, aCube.V111);

  // IPAL21120: SIGSEGV on Meshing attached Compound with Automatic Hexadralization
  if ( _indY1 < 1 || _indZ0 < 1 || _indZ1 < 1 || _indX0 < 1 || _indX1 < 1 )
    return error(COMPERR_BAD_SHAPE);

  aCube.quad_Y0 = aQuads[_indY0];
  aCube.quad_Y1 = aQuads[_indY1];
  aCube.quad_Z0 = aQuads[_indZ0];
  aCube.quad_Z1 = aQuads[_indZ1];
  aCube.quad_X0 = aQuads[_indX0];
  aCube.quad_X1 = aQuads[_indX1];

  // 1.7 - get convertion coefs from face 2D normalized to 3D normalized

  Conv2DStruct cx0;                     // for face X=0
  Conv2DStruct cx1;                     // for face X=1
  Conv2DStruct cy0;
  Conv2DStruct cy1;
  Conv2DStruct cz0;
  Conv2DStruct cz1;

  GetConv2DCoefs(*aCube.quad_X0, meshFaces[_indX0]->GetSubShape(),
                 aCube.V000, aCube.V010, aCube.V011, aCube.V001, cx0);
  GetConv2DCoefs(*aCube.quad_X1, meshFaces[_indX1]->GetSubShape(),
                 aCube.V100, aCube.V110, aCube.V111, aCube.V101, cx1);
  GetConv2DCoefs(*aCube.quad_Y0, meshFaces[_indY0]->GetSubShape(),
                 aCube.V000, aCube.V100, aCube.V101, aCube.V001, cy0);
  GetConv2DCoefs(*aCube.quad_Y1, meshFaces[_indY1]->GetSubShape(),
                 aCube.V010, aCube.V110, aCube.V111, aCube.V011, cy1);
  GetConv2DCoefs(*aCube.quad_Z0, meshFaces[_indZ0]->GetSubShape(),
                 aCube.V000, aCube.V100, aCube.V110, aCube.V010, cz0);
  GetConv2DCoefs(*aCube.quad_Z1, meshFaces[_indZ1]->GetSubShape(),
                 aCube.V001, aCube.V101, aCube.V111, aCube.V011, cz1);

  // 1.8 - create a 3D structure for normalized values
  
  int nbx = aCube.quad_Z0->side[0]->NbPoints();
  if (cz0.a1 == 0.) nbx = aCube.quad_Z0->side[1]->NbPoints();
 
  int nby = aCube.quad_X0->side[0]->NbPoints();
  if (cx0.a1 == 0.) nby = aCube.quad_X0->side[1]->NbPoints();
 
  int nbz = aCube.quad_Y0->side[0]->NbPoints();
  if (cy0.a1 != 0.) nbz = aCube.quad_Y0->side[1]->NbPoints();

  int i1, j1, nbxyz = nbx * nby * nbz;
  Point3DStruct *np = new Point3DStruct[nbxyz];

  // 1.9 - store node indexes of faces

  {
    const TopoDS_Face & F = TopoDS::Face(meshFaces[_indX0]->GetSubShape());

    faceQuadStruct *quad = aCube.quad_X0;
    int i = 0;                          // j = x/face , k = y/face
    int nbdown = quad->side[0]->NbPoints();
    int nbright = quad->side[1]->NbPoints();

    SMDS_NodeIteratorPtr itf= aMesh.GetSubMesh(F)->GetSubMeshDS()->GetNodes();
                        
    while(itf->more()) {
      const SMDS_MeshNode * node = itf->next();
      if(aTool.IsMedium(node))
        continue;
      if ( !findIJ( node, quad, i1, j1 ))
        return ClearAndReturn( aQuads, false );
      int ij1 = j1 * nbdown + i1;
      quad->uv_grid[ij1].node = node;
    }

    for (int i1 = 0; i1 < nbdown; i1++)
      for (int j1 = 0; j1 < nbright; j1++) {
        int ij1 = j1 * nbdown + i1;
        int j = cx0.ia * i1 + cx0.ib * j1 + cx0.ic;     // j = x/face
        int k = cx0.ja * i1 + cx0.jb * j1 + cx0.jc;     // k = y/face
        int ijk = k * nbx * nby + j * nbx + i;
        //MESSAGE(" "<<ij1<<" "<<i<<" "<<j<<" "<<ijk);
        np[ijk].node = quad->uv_grid[ij1].node;
        //SCRUTE(np[ijk].nodeId);
      }
  }

  {
    const TopoDS_Face & F = TopoDS::Face(meshFaces[_indX1]->GetSubShape());

    SMDS_NodeIteratorPtr itf= aMesh.GetSubMesh(F)->GetSubMeshDS()->GetNodes();

    faceQuadStruct *quad = aCube.quad_X1;
    int i = nbx - 1;            // j = x/face , k = y/face
    int nbdown = quad->side[0]->NbPoints();
    int nbright = quad->side[1]->NbPoints();

    while(itf->more()) {
      const SMDS_MeshNode * node = itf->next();
      if(aTool.IsMedium(node))
        continue;
      if ( !findIJ( node, quad, i1, j1 ))
        return ClearAndReturn( aQuads, false );
      int ij1 = j1 * nbdown + i1;
      quad->uv_grid[ij1].node = node;
    }

    for (int i1 = 0; i1 < nbdown; i1++)
      for (int j1 = 0; j1 < nbright; j1++) {
        int ij1 = j1 * nbdown + i1;
        int j = cx1.ia * i1 + cx1.ib * j1 + cx1.ic;     // j = x/face
        int k = cx1.ja * i1 + cx1.jb * j1 + cx1.jc;     // k = y/face
        int ijk = k * nbx * nby + j * nbx + i;
        //MESSAGE(" "<<ij1<<" "<<i<<" "<<j<<" "<<ijk);
        np[ijk].node = quad->uv_grid[ij1].node;
        //SCRUTE(np[ijk].nodeId);
      }
  }

  {
    const TopoDS_Face & F = TopoDS::Face(meshFaces[_indY0]->GetSubShape());

    SMDS_NodeIteratorPtr itf= aMesh.GetSubMesh(F)->GetSubMeshDS()->GetNodes();

    faceQuadStruct *quad = aCube.quad_Y0;
    int j = 0;                          // i = x/face , k = y/face
    int nbdown = quad->side[0]->NbPoints();
    int nbright = quad->side[1]->NbPoints();

    while(itf->more()) {
      const SMDS_MeshNode * node = itf->next();
      if(aTool.IsMedium(node))
        continue;
      if ( !findIJ( node, quad, i1, j1 ))
        return ClearAndReturn( aQuads, false );
      int ij1 = j1 * nbdown + i1;
      quad->uv_grid[ij1].node = node;
    }

    for (int i1 = 0; i1 < nbdown; i1++)
      for (int j1 = 0; j1 < nbright; j1++) {
        int ij1 = j1 * nbdown + i1;
        int i = cy0.ia * i1 + cy0.ib * j1 + cy0.ic;     // i = x/face
        int k = cy0.ja * i1 + cy0.jb * j1 + cy0.jc;     // k = y/face
        int ijk = k * nbx * nby + j * nbx + i;
        //MESSAGE(" "<<ij1<<" "<<i<<" "<<j<<" "<<ijk);
        np[ijk].node = quad->uv_grid[ij1].node;
        //SCRUTE(np[ijk].nodeId);
      }
  }

  {
    const TopoDS_Face & F = TopoDS::Face(meshFaces[_indY1]->GetSubShape());

    SMDS_NodeIteratorPtr itf= aMesh.GetSubMesh(F)->GetSubMeshDS()->GetNodes();

    faceQuadStruct *quad = aCube.quad_Y1;
    int j = nby - 1;            // i = x/face , k = y/face
    int nbdown = quad->side[0]->NbPoints();
    int nbright = quad->side[1]->NbPoints();

    while(itf->more()) {
      const SMDS_MeshNode * node = itf->next();
      if(aTool.IsMedium(node))
        continue;
      if ( !findIJ( node, quad, i1, j1 ))
        return ClearAndReturn( aQuads, false );
      int ij1 = j1 * nbdown + i1;
      quad->uv_grid[ij1].node = node;
    }

    for (int i1 = 0; i1 < nbdown; i1++)
      for (int j1 = 0; j1 < nbright; j1++) {
        int ij1 = j1 * nbdown + i1;
        int i = cy1.ia * i1 + cy1.ib * j1 + cy1.ic;     // i = x/face
        int k = cy1.ja * i1 + cy1.jb * j1 + cy1.jc;     // k = y/face
        int ijk = k * nbx * nby + j * nbx + i;
        //MESSAGE(" "<<ij1<<" "<<i<<" "<<j<<" "<<ijk);
        np[ijk].node = quad->uv_grid[ij1].node;
        //SCRUTE(np[ijk].nodeId);
      }
  }

  {
    const TopoDS_Face & F = TopoDS::Face(meshFaces[_indZ0]->GetSubShape());

    SMDS_NodeIteratorPtr itf= aMesh.GetSubMesh(F)->GetSubMeshDS()->GetNodes();

    faceQuadStruct *quad = aCube.quad_Z0;
    int k = 0;                          // i = x/face , j = y/face
    int nbdown = quad->side[0]->NbPoints();
    int nbright = quad->side[1]->NbPoints();

    while(itf->more()) {
      const SMDS_MeshNode * node = itf->next();
      if(aTool.IsMedium(node))
        continue;
      if ( !findIJ( node, quad, i1, j1 ))
        return ClearAndReturn( aQuads, false );
      int ij1 = j1 * nbdown + i1;
      quad->uv_grid[ij1].node = node;
    }

    for (int i1 = 0; i1 < nbdown; i1++)
      for (int j1 = 0; j1 < nbright; j1++) {
        int ij1 = j1 * nbdown + i1;
        int i = cz0.ia * i1 + cz0.ib * j1 + cz0.ic;     // i = x/face
        int j = cz0.ja * i1 + cz0.jb * j1 + cz0.jc;     // j = y/face
        int ijk = k * nbx * nby + j * nbx + i;
        //MESSAGE(" "<<ij1<<" "<<i<<" "<<j<<" "<<ijk);
        np[ijk].node = quad->uv_grid[ij1].node;
        //SCRUTE(np[ijk].nodeId);
      }
  }

  {
    const TopoDS_Face & F = TopoDS::Face(meshFaces[_indZ1]->GetSubShape());

    SMDS_NodeIteratorPtr itf= aMesh.GetSubMesh(F)->GetSubMeshDS()->GetNodes();

    faceQuadStruct *quad = aCube.quad_Z1;
    int k = nbz - 1;            // i = x/face , j = y/face
    int nbdown = quad->side[0]->NbPoints();
    int nbright = quad->side[1]->NbPoints();
    
    while(itf->more()) {
      const SMDS_MeshNode * node = itf->next();
      if(aTool.IsMedium(node))
        continue;
      if ( !findIJ( node, quad, i1, j1 ))
        return ClearAndReturn( aQuads, false );
      int ij1 = j1 * nbdown + i1;
      quad->uv_grid[ij1].node = node;
    }

    for (int i1 = 0; i1 < nbdown; i1++)
      for (int j1 = 0; j1 < nbright; j1++) {
        int ij1 = j1 * nbdown + i1;
        int i = cz1.ia * i1 + cz1.ib * j1 + cz1.ic;     // i = x/face
        int j = cz1.ja * i1 + cz1.jb * j1 + cz1.jc;     // j = y/face
        int ijk = k * nbx * nby + j * nbx + i;
        //MESSAGE(" "<<ij1<<" "<<i<<" "<<j<<" "<<ijk);
        np[ijk].node = quad->uv_grid[ij1].node;
        //SCRUTE(np[ijk].nodeId);
      }
  }

  // 2.0 - for each node of the cube:
  //       - get the 8 points 3D = 8 vertices of the cube
  //       - get the 12 points 3D on the 12 edges of the cube
  //       - get the 6 points 3D on the 6 faces with their ID
  //       - compute the point 3D
  //       - store the point 3D in SMESHDS, store its ID in 3D structure

  int shapeID = meshDS->ShapeToIndex( aShape );

  Pt3 p000, p001, p010, p011, p100, p101, p110, p111;
  Pt3 px00, px01, px10, px11;
  Pt3 p0y0, p0y1, p1y0, p1y1;
  Pt3 p00z, p01z, p10z, p11z;
  Pt3 pxy0, pxy1, px0z, px1z, p0yz, p1yz;

  GetPoint(p000, 0, 0, 0, nbx, nby, nbz, np, meshDS);
  GetPoint(p001, 0, 0, nbz - 1, nbx, nby, nbz, np, meshDS);
  GetPoint(p010, 0, nby - 1, 0, nbx, nby, nbz, np, meshDS);
  GetPoint(p011, 0, nby - 1, nbz - 1, nbx, nby, nbz, np, meshDS);
  GetPoint(p100, nbx - 1, 0, 0, nbx, nby, nbz, np, meshDS);
  GetPoint(p101, nbx - 1, 0, nbz - 1, nbx, nby, nbz, np, meshDS);
  GetPoint(p110, nbx - 1, nby - 1, 0, nbx, nby, nbz, np, meshDS);
  GetPoint(p111, nbx - 1, nby - 1, nbz - 1, nbx, nby, nbz, np, meshDS);

  for (int i = 1; i < nbx - 1; i++) {
    for (int j = 1; j < nby - 1; j++) {
      for (int k = 1; k < nbz - 1; k++) {
        // *** seulement maillage regulier
        // 12 points on edges
        GetPoint(px00, i, 0, 0, nbx, nby, nbz, np, meshDS);
        GetPoint(px01, i, 0, nbz - 1, nbx, nby, nbz, np, meshDS);
        GetPoint(px10, i, nby - 1, 0, nbx, nby, nbz, np, meshDS);
        GetPoint(px11, i, nby - 1, nbz - 1, nbx, nby, nbz, np, meshDS);

        GetPoint(p0y0, 0, j, 0, nbx, nby, nbz, np, meshDS);
        GetPoint(p0y1, 0, j, nbz - 1, nbx, nby, nbz, np, meshDS);
        GetPoint(p1y0, nbx - 1, j, 0, nbx, nby, nbz, np, meshDS);
        GetPoint(p1y1, nbx - 1, j, nbz - 1, nbx, nby, nbz, np, meshDS);

        GetPoint(p00z, 0, 0, k, nbx, nby, nbz, np, meshDS);
        GetPoint(p01z, 0, nby - 1, k, nbx, nby, nbz, np, meshDS);
        GetPoint(p10z, nbx - 1, 0, k, nbx, nby, nbz, np, meshDS);
        GetPoint(p11z, nbx - 1, nby - 1, k, nbx, nby, nbz, np, meshDS);

        // 12 points on faces
        GetPoint(pxy0, i, j, 0, nbx, nby, nbz, np, meshDS);
        GetPoint(pxy1, i, j, nbz - 1, nbx, nby, nbz, np, meshDS);
        GetPoint(px0z, i, 0, k, nbx, nby, nbz, np, meshDS);
        GetPoint(px1z, i, nby - 1, k, nbx, nby, nbz, np, meshDS);
        GetPoint(p0yz, 0, j, k, nbx, nby, nbz, np, meshDS);
        GetPoint(p1yz, nbx - 1, j, k, nbx, nby, nbz, np, meshDS);

        int ijk = k * nbx * nby + j * nbx + i;
        double x = double (i) / double (nbx - 1);       // *** seulement
        double y = double (j) / double (nby - 1);       // *** maillage
        double z = double (k) / double (nbz - 1);       // *** regulier

        Pt3 X;
        for (int i = 0; i < 3; i++) {
          X[i] = (1 - x) * p0yz[i] + x * p1yz[i]
                 + (1 - y) * px0z[i] + y * px1z[i]
                 + (1 - z) * pxy0[i] + z * pxy1[i]
                 - (1 - x) * ((1 - y) * p00z[i] + y * p01z[i])
                 - x * ((1 - y) * p10z[i] + y * p11z[i])
                 - (1 - y) * ((1 - z) * px00[i] + z * px01[i])
                 - y * ((1 - z) * px10[i] + z * px11[i])
                 - (1 - z) * ((1 - x) * p0y0[i] + x * p1y0[i])
                 - z * ((1 - x) * p0y1[i] + x * p1y1[i])
                 + (1 - x) * ((1 - y) * ((1 - z) * p000[i] + z * p001[i])
                 + y * ((1 - z) * p010[i] + z * p011[i]))
                 + x * ((1 - y) * ((1 - z) * p100[i] + z * p101[i])
                 + y * ((1 - z) * p110[i] + z * p111[i]));
        }

        SMDS_MeshNode * node = meshDS->AddNode(X[0], X[1], X[2]);
        np[ijk].node = node;
        meshDS->SetNodeInVolume(node, shapeID);
      }
    }
  }

  // find orientation of furute volumes according to MED convention
  vector< bool > forward( nbx * nby );
  SMDS_VolumeTool vTool;
  for (int i = 0; i < nbx - 1; i++) {
    for (int j = 0; j < nby - 1; j++) {
      int n1 = j * nbx + i;
      int n2 = j * nbx + i + 1;
      int n3 = (j + 1) * nbx + i + 1;
      int n4 = (j + 1) * nbx + i;
      int n5 = nbx * nby + j * nbx + i;
      int n6 = nbx * nby + j * nbx + i + 1;
      int n7 = nbx * nby + (j + 1) * nbx + i + 1;
      int n8 = nbx * nby + (j + 1) * nbx + i;

      SMDS_VolumeOfNodes tmpVol (np[n1].node,np[n2].node,np[n3].node,np[n4].node,
                                 np[n5].node,np[n6].node,np[n7].node,np[n8].node);
      vTool.Set( &tmpVol );
      forward[ n1 ] = vTool.IsForward();
    }
  }

  //2.1 - for each node of the cube (less 3 *1 Faces):
  //      - store hexahedron in SMESHDS
  MESSAGE("Storing hexahedron into the DS");
  for (int i = 0; i < nbx - 1; i++) {
    for (int j = 0; j < nby - 1; j++) {
      bool isForw = forward.at( j * nbx + i );
      for (int k = 0; k < nbz - 1; k++) {
        int n1 = k * nbx * nby + j * nbx + i;
        int n2 = k * nbx * nby + j * nbx + i + 1;
        int n3 = k * nbx * nby + (j + 1) * nbx + i + 1;
        int n4 = k * nbx * nby + (j + 1) * nbx + i;
        int n5 = (k + 1) * nbx * nby + j * nbx + i;
        int n6 = (k + 1) * nbx * nby + j * nbx + i + 1;
        int n7 = (k + 1) * nbx * nby + (j + 1) * nbx + i + 1;
        int n8 = (k + 1) * nbx * nby + (j + 1) * nbx + i;

        SMDS_MeshVolume * elt;
        if ( isForw ) {
          elt = aTool.AddVolume(np[n1].node, np[n2].node,
                                np[n3].node, np[n4].node,
                                np[n5].node, np[n6].node,
                                np[n7].node, np[n8].node);
        }
        else {
          elt = aTool.AddVolume(np[n1].node, np[n4].node,
                                np[n3].node, np[n2].node,
                                np[n5].node, np[n8].node,
                                np[n7].node, np[n6].node);
        }
        
        meshDS->SetMeshElementOnShape(elt, shapeID);
      }
    }
  }
  if ( np ) delete [] np;
  return ClearAndReturn( aQuads, true );
}