+
+ //================================================================================
+ /*!
+ * \brief Place medium nodes at the link middle for elements whose corner nodes
+ * are out of geometrical boundary to prevent distorting elements.
+ * Issue 0020982, note 0013990
+ */
+ //================================================================================
+
+ void force3DOutOfBoundary( SMESH_MesherHelper& theHelper,
+ SMESH_ComputeErrorPtr& theError)
+ {
+ SMESHDS_Mesh* meshDS = theHelper.GetMeshDS();
+ TopoDS_Shape shape = theHelper.GetSubShape().Oriented( TopAbs_FORWARD );
+ if ( shape.IsNull() ) return;
+
+ if ( !theError ) theError = SMESH_ComputeError::New();
+
+ gp_XYZ faceNorm;
+
+ if ( shape.ShapeType() == TopAbs_FACE ) // 2D
+ {
+ if ( theHelper.GetMesh()->NbTriangles( ORDER_QUADRATIC ) < 1 ) return;
+
+ SMESHDS_SubMesh* faceSM = meshDS->MeshElements( shape );
+ if ( !faceSM ) return;
+
+ const TopoDS_Face& face = TopoDS::Face( shape );
+ Handle(Geom_Surface) surface = BRep_Tool::Surface( face );
+
+ TopExp_Explorer edgeIt( face, TopAbs_EDGE );
+ for ( ; edgeIt.More(); edgeIt.Next() ) // loop on EDGEs of a FACE
+ {
+ // check if the EDGE needs checking
+ const TopoDS_Edge& edge = TopoDS::Edge( edgeIt.Current() );
+ if ( BRep_Tool::Degenerated( edge ) )
+ continue;
+ if ( theHelper.IsRealSeam( edge ) &&
+ edge.Orientation() == TopAbs_REVERSED )
+ continue;
+
+ SMESHDS_SubMesh* edgeSM = meshDS->MeshElements( edge );
+ if ( !edgeSM ) continue;
+
+ double f,l;
+ Handle(Geom2d_Curve) pcurve = BRep_Tool::CurveOnSurface( edge, face, f, l );
+ BRepAdaptor_Curve curve3D( edge );
+ switch ( curve3D.GetType() ) {
+ case GeomAbs_Line: continue;
+ case GeomAbs_Circle:
+ case GeomAbs_Ellipse:
+ case GeomAbs_Hyperbola:
+ case GeomAbs_Parabola:
+ try
+ {
+ gp_Vec D1, D2, Du1, Dv1; gp_Pnt p;
+ curve3D.D2( 0.5 * ( f + l ), p, D1, D2 );
+ gp_Pnt2d uv = pcurve->Value( 0.5 * ( f + l ) );
+ surface->D1( uv.X(), uv.Y(), p, Du1, Dv1 );
+ gp_Vec fNorm = Du1 ^ Dv1;
+ if ( fNorm.IsParallel( D2, M_PI * 25./180. ))
+ continue; // face is normal to the curve3D
+
+ gp_Vec curvNorm = fNorm ^ D1;
+ if ( edge.Orientation() == TopAbs_REVERSED ) curvNorm.Reverse();
+ if ( curvNorm * D2 > 0 )
+ continue; // convex edge
+ }
+ catch ( Standard_Failure )
+ {
+ continue;
+ }
+ }
+ // get nodes shared by faces that may be distorted
+ SMDS_NodeIteratorPtr nodeIt;
+ if ( edgeSM->NbNodes() > 0 ) {
+ nodeIt = edgeSM->GetNodes();
+ }
+ else {
+ SMESHDS_SubMesh* vertexSM = meshDS->MeshElements( theHelper.IthVertex( 0, edge ));
+ if ( !vertexSM )
+ vertexSM = meshDS->MeshElements( theHelper.IthVertex( 1, edge ));
+ if ( !vertexSM ) continue;
+ nodeIt = vertexSM->GetNodes();
+ }
+
+ // find suspicious faces
+ TIDSortedElemSet checkedFaces;
+ vector< const SMDS_MeshNode* > nOnEdge( 2 );
+ const SMDS_MeshNode* nOnFace;
+ while ( nodeIt->more() )
+ {
+ const SMDS_MeshNode* n = nodeIt->next();
+ SMDS_ElemIteratorPtr faceIt = n->GetInverseElementIterator( SMDSAbs_Face );
+ while ( faceIt->more() )
+ {
+ const SMDS_MeshElement* f = faceIt->next();
+ if ( !faceSM->Contains( f ) ||
+ f->NbNodes() != 6 || // check quadratic triangles only
+ !checkedFaces.insert( f ).second )
+ continue;
+
+ // get nodes on EDGE and on FACE of a suspicious face
+ nOnEdge.clear(); nOnFace = 0;
+ SMDS_MeshElement::iterator triNode = f->begin_nodes();
+ for ( int nbN = 0; nbN < 3; ++triNode, ++nbN )
+ {
+ n = *triNode;
+ if ( n->GetPosition()->GetDim() == 2 )
+ nOnFace = n;
+ else
+ nOnEdge.push_back( n );
+ }
+
+ // check if nOnFace is inside the FACE
+ if ( nOnFace && nOnEdge.size() == 2 )
+ {
+ theHelper.AddTLinks( static_cast< const SMDS_MeshFace* > ( f ));
+ if ( !SMESH_Algo::FaceNormal( f, faceNorm, /*normalized=*/false ))
+ continue;
+ gp_XYZ edgeDir = SMESH_TNodeXYZ( nOnEdge[0] ) - SMESH_TNodeXYZ( nOnEdge[1] );
+ gp_XYZ edgeNorm = faceNorm ^ edgeDir;
+ n = theHelper.GetMediumNode( nOnEdge[0], nOnEdge[1], true );
+ gp_XYZ pN0 = SMESH_TNodeXYZ( nOnEdge[0] );
+ gp_XYZ pMedium = SMESH_TNodeXYZ( n ); // on-edge node location
+ gp_XYZ pFaceN = SMESH_TNodeXYZ( nOnFace ); // on-face node location
+ double hMedium = edgeNorm * gp_Vec( pN0, pMedium ).XYZ();
+ double hFace = edgeNorm * gp_Vec( pN0, pFaceN ).XYZ();
+ if ( Abs( hMedium ) > Abs( hFace * 0.6 ))
+ {
+ // nOnFace is out of FACE, move a medium on-edge node to the middle
+ gp_XYZ pMid3D = 0.5 * ( pN0 + SMESH_TNodeXYZ( nOnEdge[1] ));
+ meshDS->MoveNode( n, pMid3D.X(), pMid3D.Y(), pMid3D.Z() );
+ MSG( "move OUT of face " << n );
+ theError->myBadElements.push_back( f );
+ }
+ }
+ }
+ }
+ }
+ if ( !theError->myBadElements.empty() )
+ theError->myName = EDITERR_NO_MEDIUM_ON_GEOM;
+ return;
+
+ } // 2D ==============================================================================
+
+ if ( shape.ShapeType() == TopAbs_SOLID ) // 3D
+ {
+ if ( theHelper.GetMesh()->NbTetras ( ORDER_QUADRATIC ) < 1 &&
+ theHelper.GetMesh()->NbPyramids( ORDER_QUADRATIC ) < 1 ) return;
+
+ SMESHDS_SubMesh* solidSM = meshDS->MeshElements( shape );
+ if ( !solidSM ) return;
+
+ // check if the SOLID is bound by concave FACEs
+ vector< TopoDS_Face > concaveFaces;
+ TopExp_Explorer faceIt( shape, TopAbs_FACE );
+ for ( ; faceIt.More(); faceIt.Next() ) // loop on FACEs of a SOLID
+ {
+ const TopoDS_Face& face = TopoDS::Face( faceIt.Current() );
+ if ( !meshDS->MeshElements( face )) continue;
+
+ BRepAdaptor_Surface surface( face );
+ switch ( surface.GetType() ) {
+ case GeomAbs_Plane: continue;
+ case GeomAbs_Cylinder:
+ case GeomAbs_Cone:
+ case GeomAbs_Sphere:
+ try
+ {
+ double u = 0.5 * ( surface.FirstUParameter() + surface.LastUParameter() );
+ double v = 0.5 * ( surface.FirstVParameter() + surface.LastVParameter() );
+ gp_Vec Du1, Dv1, Du2, Dv2, Duv2; gp_Pnt p;
+ surface.D2( u,v, p, Du1, Dv1, Du2, Dv2, Duv2 );
+ gp_Vec fNorm = Du1 ^ Dv1;
+ if ( face.Orientation() == TopAbs_REVERSED ) fNorm.Reverse();
+ bool concaveU = ( fNorm * Du2 > 1e-100 );
+ bool concaveV = ( fNorm * Dv2 > 1e-100 );
+ if ( concaveU || concaveV )
+ concaveFaces.push_back( face );
+ }
+ catch ( Standard_Failure )
+ {
+ concaveFaces.push_back( face );
+ }
+ }
+ }
+ if ( concaveFaces.empty() )
+ return;
+
+ // fix 2D mesh on the SOLID
+ for ( faceIt.ReInit(); faceIt.More(); faceIt.Next() ) // loop on FACEs of a SOLID
+ {
+ SMESH_MesherHelper faceHelper( *theHelper.GetMesh() );
+ faceHelper.SetSubShape( faceIt.Current() );
+ force3DOutOfBoundary( faceHelper, theError );
+ }
+
+ // get an iterator over faces on concaveFaces
+ vector< SMDS_ElemIteratorPtr > faceIterVec( concaveFaces.size() );
+ for ( size_t i = 0; i < concaveFaces.size(); ++i )
+ faceIterVec[i] = meshDS->MeshElements( concaveFaces[i] )->GetElements();
+ typedef SMDS_IteratorOnIterators
+ < const SMDS_MeshElement*, vector< SMDS_ElemIteratorPtr > > TIterOnIter;
+ SMDS_ElemIteratorPtr faceIter( new TIterOnIter( faceIterVec ));
+
+ // a seacher to check if a volume is close to a concave face
+ std::auto_ptr< SMESH_ElementSearcher > faceSearcher
+ ( SMESH_MeshEditor( theHelper.GetMesh() ).GetElementSearcher( faceIter ));
+
+ // classifier
+ //BRepClass3d_SolidClassifier solidClassifier( shape );
+
+ TIDSortedElemSet checkedVols, movedNodes;
+ for ( faceIt.ReInit(); faceIt.More(); faceIt.Next() ) // loop on FACEs of a SOLID
+ {
+ const TopoDS_Shape& face = faceIt.Current();
+ SMESHDS_SubMesh* faceSM = meshDS->MeshElements( face );
+ if ( !faceSM ) continue;
+
+ // get nodes shared by volumes (tet and pyra) on the FACE that may be distorted
+ SMDS_NodeIteratorPtr nodeIt;
+ if ( faceSM->NbNodes() > 0 ) {
+ nodeIt = faceSM->GetNodes();
+ }
+ else {
+ TopExp_Explorer vertex( face, TopAbs_VERTEX );
+ SMESHDS_SubMesh* vertexSM = meshDS->MeshElements( vertex.Current() );
+ if ( !vertexSM ) continue;
+ nodeIt = vertexSM->GetNodes();
+ }
+
+ // find suspicious volumes adjacent to the FACE
+ vector< const SMDS_MeshNode* > nOnFace( 4 );
+ const SMDS_MeshNode* nInSolid;
+ //vector< const SMDS_MeshElement* > intersectedFaces;
+ while ( nodeIt->more() )
+ {
+ const SMDS_MeshNode* n = nodeIt->next();
+ SMDS_ElemIteratorPtr volIt = n->GetInverseElementIterator( SMDSAbs_Volume );
+ while ( volIt->more() )
+ {
+ const SMDS_MeshElement* vol = volIt->next();
+ int nbN = vol->NbCornerNodes();
+ if ( ( nbN != 4 && nbN != 5 ) ||
+ !solidSM->Contains( vol ) ||
+ !checkedVols.insert( vol ).second )
+ continue;
+
+ // get nodes on FACE and in SOLID of a suspicious volume
+ nOnFace.clear(); nInSolid = 0;
+ SMDS_MeshElement::iterator volNode = vol->begin_nodes();
+ for ( int nb = nbN; nb > 0; ++volNode, --nb )
+ {
+ n = *volNode;
+ if ( n->GetPosition()->GetDim() == 3 )
+ nInSolid = n;
+ else
+ nOnFace.push_back( n );
+ }
+ if ( !nInSolid || nOnFace.size() != nbN - 1 )
+ continue;
+
+ // get size of the vol
+ SMESH_TNodeXYZ pInSolid( nInSolid ), pOnFace0( nOnFace[0] );
+ double volLength = pInSolid.SquareDistance( nOnFace[0] );
+ for ( size_t i = 1; i < nOnFace.size(); ++i )
+ {
+ volLength = Max( volLength, pOnFace0.SquareDistance( nOnFace[i] ));
+ }
+
+ // check if vol is close to concaveFaces
+ const SMDS_MeshElement* closeFace =
+ faceSearcher->FindClosestTo( pInSolid, SMDSAbs_Face );
+ if ( !closeFace ||
+ pInSolid.SquareDistance( closeFace->GetNode(0) ) > 4 * volLength )
+ continue;
+
+ // check if vol is distorted, i.e. a medium node is much closer
+ // to nInSolid than the link middle
+ bool isDistorted = false;
+ SMDS_FaceOfNodes onFaceTria( nOnFace[0], nOnFace[1], nOnFace[2] );
+ if ( !SMESH_Algo::FaceNormal( &onFaceTria, faceNorm, /*normalized=*/false ))
+ continue;
+ theHelper.AddTLinks( static_cast< const SMDS_MeshVolume* > ( vol ));
+ vector< pair< SMESH_TLink, const SMDS_MeshNode* > > links;
+ for ( size_t i = 0; i < nOnFace.size(); ++i ) // loop on links between nOnFace
+ for ( size_t j = i+1; j < nOnFace.size(); ++j )
+ {
+ SMESH_TLink link( nOnFace[i], nOnFace[j] );
+ TLinkNodeMap::const_iterator linkIt =
+ theHelper.GetTLinkNodeMap().find( link );
+ if ( linkIt != theHelper.GetTLinkNodeMap().end() )
+ {
+ links.push_back( make_pair( linkIt->first, linkIt->second ));
+ if ( !isDistorted ) {
+ // compare projections of nInSolid and nMedium to face normal
+ gp_Pnt pMedium = SMESH_TNodeXYZ( linkIt->second );
+ double hMedium = faceNorm * gp_Vec( pOnFace0, pMedium ).XYZ();
+ double hVol = faceNorm * gp_Vec( pOnFace0, pInSolid ).XYZ();
+ isDistorted = ( Abs( hMedium ) > Abs( hVol * 0.5 ));
+ }
+ }
+ }
+ // move medium nodes to link middle
+ if ( isDistorted )
+ {
+ for ( size_t i = 0; i < links.size(); ++i )
+ {
+ const SMDS_MeshNode* nMedium = links[i].second;
+ if ( movedNodes.insert( nMedium ).second )
+ {
+ gp_Pnt pMid3D = 0.5 * ( SMESH_TNodeXYZ( links[i].first.node1() ) +
+ SMESH_TNodeXYZ( links[i].first.node2() ));
+ meshDS->MoveNode( nMedium, pMid3D.X(), pMid3D.Y(), pMid3D.Z() );
+ MSG( "move OUT of solid " << nMedium );
+ }
+ }
+ theError->myBadElements.push_back( vol );
+ }
+ } // loop on volumes sharing a node on FACE
+ } // loop on nodes on FACE
+ } // loop on FACEs of a SOLID
+
+ if ( !theError->myBadElements.empty() )
+ theError->myName = EDITERR_NO_MEDIUM_ON_GEOM;
+ } // 3D case
+ }
+
+} //namespace