public static _AcDb.ResultBuffer GetNonPlottableLayers(_AcDb.ResultBuffer rb)
        {
            List <string> layerNames = new List <string>();

            Globs.GetNonPlottableLayers(layerNames);

            if (layerNames.Count > 0)
            {
                _AcDb.ResultBuffer rbRet = new _AcDb.ResultBuffer();
                foreach (var name in layerNames)
                {
                    rbRet.Add(new _AcDb.TypedValue((int)_AcBrx.LispDataType.Text, name));
                }
                return(rbRet);
            }
            else
            {
                return(null);
            }
        }