+ typedef list< pair< const SMDS_MeshNode*, const BRepMesh_Triangle* > > TNodeTriaList;
+
+ //================================================================================
+ /*!
+ * \brief Add in-FACE nodes surrounding a given node to a queue
+ */
+ //================================================================================
+
+ void addCloseNodes( const SMDS_MeshNode* srcNode,
+ const BRepMesh_Triangle* bmTria,
+ const int srcFaceID,
+ TNodeTriaList & noTriQueue )
+ {
+ // find in-FACE nodes
+ SMDS_ElemIteratorPtr elems = srcNode->GetInverseElementIterator(SMDSAbs_Face);
+ while ( elems->more() )
+ {
+ const SMDS_MeshElement* elem = elems->next();
+ if ( elem->getshapeId() == srcFaceID )
+ {
+ for ( int i = 0, nb = elem->NbNodes(); i < nb; ++i )
+ {
+ const SMDS_MeshNode* n = elem->GetNode( i );
+ if ( !n->isMarked() )
+ noTriQueue.push_back( make_pair( n, bmTria ));
+ }
+ }
+ }
+ }
+
+ //================================================================================
+ /*!
+ * \brief Find a delauney triangle containing a given 2D point and return
+ * barycentric coordinates within the found triangle
+ */
+ //================================================================================
+
+ const BRepMesh_Triangle* findTriangle( const gp_XY& uv,
+ const BRepMesh_Triangle* bmTria,
+ Handle(BRepMesh_DataStructureOfDelaun)& triaDS,
+ double bc[3] )
+ {
+ int nodeIDs[3];
+ gp_XY nodeUVs[3];
+ int linkIDs[3];
+ Standard_Boolean ori[3];
+
+ while ( bmTria )
+ {
+ // check bmTria
+
+ triaDS->ElementNodes( *bmTria, nodeIDs );
+ nodeUVs[0] = triaDS->GetNode( nodeIDs[0] ).Coord();
+ nodeUVs[1] = triaDS->GetNode( nodeIDs[1] ).Coord();
+ nodeUVs[2] = triaDS->GetNode( nodeIDs[2] ).Coord();
+
+ SMESH_MeshAlgos::GetBarycentricCoords( uv,
+ nodeUVs[0], nodeUVs[1], nodeUVs[2],
+ bc[0], bc[1] );
+ if ( bc[0] >= 0 && bc[1] >= 0 && bc[0] + bc[1] <= 1 )
+ {
+ bc[2] = 1 - bc[0] - bc[1];
+ return bmTria;
+ }
+
+ // look for a neighbor triangle, which is adjacent to a link intersected
+ // by a segment( triangle center -> uv )
+
+ gp_XY gc = ( nodeUVs[0] + nodeUVs[1] + nodeUVs[2] ) / 3.;
+ gp_XY seg = uv - gc;
+
+ bmTria->Edges( linkIDs, ori );
+ int triaID = triaDS->IndexOf( *bmTria );
+ bmTria = 0;
+
+ for ( int i = 0; i < 3; ++i )
+ {
+ const BRepMesh_PairOfIndex & triIDs = triaDS->ElementsConnectedTo( linkIDs[i] );
+ if ( triIDs.Extent() < 2 )
+ continue; // no neighbor triangle
+
+ // check if a link intersects gc2uv
+ const BRepMesh_Edge & link = triaDS->GetLink( linkIDs[i] );
+ const BRepMesh_Vertex & n1 = triaDS->GetNode( link.FirstNode() );
+ const BRepMesh_Vertex & n2 = triaDS->GetNode( link.LastNode() );
+ gp_XY uv1 = n1.Coord();
+ gp_XY lin = n2.Coord() - uv1; // link direction
+
+ double crossSegLin = seg ^ lin;
+ if ( Abs( crossSegLin ) < std::numeric_limits<double>::min() )
+ continue; // parallel
+
+ double uSeg = ( uv1 - gc ) ^ lin / crossSegLin;
+ if ( 0. <= uSeg && uSeg <= 1. )
+ {
+ bmTria = & triaDS->GetElement( triIDs.Index( 1 + ( triIDs.Index(1) == triaID )));
+ break;
+ }
+ }
+ }
+ return bmTria;
+ }
+
+ //================================================================================
+ /*!
+ * \brief Morph mesh on the target face to lie within FACE boundary w/o distortion
+ *
+ * algo:
+ * - make a CDT on the src FACE
+ * - find a triangle containing a src node and get its barycentric coordinates
+ * - move the node to a point with the same barycentric coordinates in a corresponding
+ * tgt triangle
+ */
+ //================================================================================
+
+ bool morph( SMESH_MesherHelper& tgtHelper,
+ const TopoDS_Face& tgtFace,
+ const TopoDS_Face& srcFace,
+ const TSideVector& tgtWires,
+ const TSideVector& srcWires,
+ const TAssocTool::TNodeNodeMap& src2tgtNodes )
+ {
+ if ( srcWires.size() != tgtWires.size() ) return false;
+ if ( srcWires.size() == 1 ) return false; // tmp
+
+ // count boundary points
+ int iP = 1, nbP = 0;
+ for ( size_t iW = 0; iW < srcWires.size(); ++iW )
+ nbP += srcWires[iW]->NbPoints() - 1; // 1st and last points coincide
+
+ // fill boundary points
+ BRepMesh::Array1OfVertexOfDelaun srcVert( 1, 1 + nbP ), tgtVert( 1, 1 + nbP );
+ vector< const SMDS_MeshNode* > bndSrcNodes( nbP + 1 ); bndSrcNodes[0] = 0;
+ BRepMesh_Vertex v( 0, 0, BRepMesh_Frontier );
+ for ( size_t iW = 0; iW < srcWires.size(); ++iW )
+ {
+ const UVPtStructVec& srcPnt = srcWires[iW]->GetUVPtStruct();
+ const UVPtStructVec& tgtPnt = tgtWires[iW]->GetUVPtStruct();
+ if ( srcPnt.size() != tgtPnt.size() ) return false;
+
+ for ( int i = 0, nb = srcPnt.size() - 1; i < nb; ++i, ++iP )
+ {
+ bndSrcNodes[ iP ] = srcPnt[i].node;
+ srcPnt[i].node->setIsMarked( true );
+
+ v.ChangeCoord() = srcPnt[i].UV();
+ srcVert( iP ) = v;
+ v.ChangeCoord() = tgtPnt[i].UV();
+ tgtVert( iP ) = v;
+ }
+ }
+ // triangulate the srcFace in 2D
+ BRepMesh_Delaun delauney( srcVert );
+ Handle(BRepMesh_DataStructureOfDelaun) triaDS = delauney.Result();
+
+ Handle(ShapeAnalysis_Surface) tgtSurface = tgtHelper.GetSurface( tgtFace );
+ SMESHDS_Mesh* srcMesh = srcWires[0]->GetMesh()->GetMeshDS();
+ SMESHDS_Mesh* tgtMesh = tgtHelper.GetMeshDS();
+ const SMDS_MeshNode *srcNode, *tgtNode;
+ const BRepMesh_Triangle *bmTria;
+
+ // un-mark internal src nodes; later we will mark moved nodes
+ SMDS_NodeIteratorPtr nIt = srcMesh->MeshElements( srcFace )->GetNodes();
+ if ( !nIt || !nIt->more() ) return true;
+ while ( nIt->more() )
+ ( srcNode = nIt->next() )->setIsMarked( false );
+
+ // initialize a queue of nodes with starting triangles
+ const int srcFaceID = srcNode->getshapeId();
+ TNodeTriaList noTriQueue;
+ size_t iBndSrcN = 1;
+ for ( ; iBndSrcN < bndSrcNodes.size() && noTriQueue.empty(); ++iBndSrcN )
+ {
+ // get a triangle
+ const BRepMesh::ListOfInteger & linkIds = triaDS->LinksConnectedTo( iBndSrcN );
+ const BRepMesh_PairOfIndex & triaIds = triaDS->ElementsConnectedTo( linkIds.First() );
+ const BRepMesh_Triangle& tria = triaDS->GetElement( triaIds.Index(1) );
+
+ addCloseNodes( bndSrcNodes[ iBndSrcN ], &tria, srcFaceID, noTriQueue );
+ }
+
+ // Move tgt nodes
+
+ double bc[3]; // barycentric coordinates
+ int nodeIDs[3];
+ bool checkUV = true;
+ const SMDS_FacePosition* pos;
+
+ while ( !noTriQueue.empty() )
+ {
+ srcNode = noTriQueue.front().first;
+ bmTria = noTriQueue.front().second;
+ noTriQueue.pop_front();
+ if ( srcNode->isMarked() )
+ continue;
+ srcNode->setIsMarked( true );
+
+ // find a delauney triangle containing the src node
+ gp_XY uv = tgtHelper.GetNodeUV( srcFace, srcNode, NULL, &checkUV );
+ bmTria = findTriangle( uv, bmTria, triaDS, bc );
+ if ( !bmTria )
+ continue;
+
+ // compute new coordinates for a corresponding tgt node
+ gp_XY uvNew( 0., 0. ), nodeUV;
+ triaDS->ElementNodes( *bmTria, nodeIDs );
+ for ( int i = 0; i < 3; ++i )
+ uvNew += bc[i] * tgtVert( nodeIDs[i]).Coord();
+ gp_Pnt xyz = tgtSurface->Value( uvNew );
+
+ // find and move tgt node
+ TAssocTool::TNodeNodeMap::const_iterator n2n = src2tgtNodes.find( srcNode );
+ if ( n2n == src2tgtNodes.end() ) continue;
+ tgtNode = n2n->second;
+ tgtMesh->MoveNode( tgtNode, xyz.X(), xyz.Y(), xyz.Z() );
+
+ if (( pos = dynamic_cast< const SMDS_FacePosition* >( tgtNode->GetPosition() )))
+ const_cast<SMDS_FacePosition*>( pos )->SetParameters( uvNew.X(), uvNew.Y() );
+
+ addCloseNodes( srcNode, bmTria, srcFaceID, noTriQueue );
+
+ // assure that all src nodes are visited
+ for ( ; iBndSrcN < bndSrcNodes.size() && noTriQueue.empty(); ++iBndSrcN )
+ {
+ const BRepMesh::ListOfInteger & linkIds = triaDS->LinksConnectedTo( iBndSrcN );
+ const BRepMesh_PairOfIndex & triaIds = triaDS->ElementsConnectedTo( linkIds.First() );
+ const BRepMesh_Triangle& tria = triaDS->GetElement( triaIds.Index(1) );
+ addCloseNodes( bndSrcNodes[ iBndSrcN ], &tria, srcFaceID, noTriQueue );
+ }
+ }
+
+ return true;
+ }
+