///<summary> This gets called when when the user runs this command.</summary>
        public override IRhinoCommand.result RunCommand(IRhinoCommandContext context)
        {
            MRhinoGetObject go = new MRhinoGetObject();

            go.SetCommandPrompt("Select surface, polysurface, or mesh to export");
            go.SetGeometryFilter(IRhinoGetObject.GEOMETRY_TYPE_FILTER.surface_object | IRhinoGetObject.GEOMETRY_TYPE_FILTER.polysrf_object | IRhinoGetObject.GEOMETRY_TYPE_FILTER.mesh_object);
            go.GetObjects(1, 1);
            if (go.CommandResult() != IRhinoCommand.result.success)
            {
                return(go.CommandResult());
            }

            MRhinoObjRef obj_ref = go.Object(0);

            IRhinoObject obj = obj_ref.Object();

            if (null == obj)
            {
                return(IRhinoCommand.result.failure);
            }

            List <IRhinoObject> obj_list = new List <IRhinoObject>();

            obj_list.Add(obj);

            ArrayMRhinoObjectMesh mesh_list       = new ArrayMRhinoObjectMesh(obj_list.Count);
            OnMeshParameters      mesh_parameters = _mesh_parameters;
            int mesh_ui_style = !context.IsInteractive() ? 2 : _mesh_ui_style;

            IRhinoCommand.result res = RhUtil.RhinoMeshObjects(obj_list.ToArray(), ref mesh_parameters, ref mesh_ui_style, ref mesh_list);
            if (res == IRhinoCommand.result.success)
            {
                if (mesh_ui_style >= 0 && mesh_ui_style <= 1)
                {
                    _mesh_ui_style = mesh_ui_style;
                }
                _mesh_parameters = mesh_parameters;
            }
            else
            {
                RhUtil.RhinoApp().Print("No mesh to export.\n");
                return(res);
            }

            string filename = string.Empty;

            if (context.IsInteractive())
            {
                SaveFileDialog dialog = new SaveFileDialog();
                dialog.Title            = "Export";
                dialog.Filter           = "Geomview files|*.off";
                dialog.InitialDirectory = DirectoryManager.DefaultDirectory(DirectoryManager.FileTypes.ftExport);
                if (dialog.ShowDialog() != DialogResult.OK)
                {
                    return(IRhinoCommand.result.cancel);
                }

                filename = dialog.FileName;
            }
            else
            {
                MRhinoGetString gs = new MRhinoGetString();
                gs.SetCommandPrompt("Export file name");
                gs.GetString();
                if (gs.CommandResult() != IRhinoCommand.result.success)
                {
                    return(gs.CommandResult());
                }

                filename = gs.String().Trim();
            }

            try
            {
                OnMesh mesh = mesh_list.First().GetMesh();

                int vertex_count = mesh.VertexCount();
                int face_count   = mesh.FaceCount();
                int edge_count   = mesh.Topology().m_tope.Count();

                System.IO.StreamWriter file = new System.IO.StreamWriter(filename);

                // Write out the first line of the file header
                file.WriteLine("OFF");

                // Write the header information
                file.WriteLine(string.Format("{0} {1} {2}", vertex_count, face_count, edge_count));

                file.WriteLine();

                // Write out all the vertices in order
                for (int i = 0; i < vertex_count; i++)
                {
                    On3fPoint p = mesh.m_V[i];
                    file.WriteLine(string.Format("{0} {1} {2}", p.x.ToString("F"), p.y.ToString("F"), p.z.ToString("F")));
                }

                file.WriteLine();

                // Write out all the faces
                for (int i = 0; i < face_count; i++)
                {
                    OnMeshFace f = mesh.m_F[i];
                    if (f.IsQuad())
                    {
                        file.WriteLine(string.Format("4 {0} {1} {2} {3}", f.get_vi(0), f.get_vi(1), f.get_vi(2), f.get_vi(3)));
                    }
                    else
                    {
                        file.WriteLine(string.Format("3 {0} {1} {2}", f.get_vi(0), f.get_vi(1), f.get_vi(2)));
                    }
                }

                file.Close();
            }
            catch (Exception e)
            {
                RhUtil.RhinoApp().Print(string.Format("{0}\n", e.Message));
            }

            return(IRhinoCommand.result.success);
        }