uvOK = CheckNodeUV( F, n, uv.ChangeCoord(), BRep_Tool::Tolerance( E ));
// for a node on a seam edge select one of UVs on 2 pcurves
uvOK = CheckNodeUV( F, n, uv.ChangeCoord(), BRep_Tool::Tolerance( E ));
// for a node on a seam edge select one of UVs on 2 pcurves