public Chart3D(Viewport3D mainViewport)
        {
            this.mainViewport = mainViewport;
            // selection rect
            m_selectRect.SetRect(new Point(-0.5, -0.5), new Point(-0.5, -0.5));
            WPFChart3D.Model3D model3d = new WPFChart3D.Model3D();
            ArrayList          meshs   = m_selectRect.GetMeshes();

            m_nRectModelIndex = model3d.UpdateModel(meshs, null, m_nRectModelIndex, this.mainViewport);
        }
        public _3D_WPF_Chart()
        {
            InitializeComponent();
            // selection rect
            m_selectRect.SetRect(new Point(-0.5, -0.5), new Point(-0.5, -0.5));
            WPFChart3D.Model3D model3d = new WPFChart3D.Model3D();
            ArrayList          meshs   = m_selectRect.GetMeshes();

            m_nRectModelIndex = model3d.UpdateModel(meshs, null, m_nRectModelIndex, this.mainViewport);

            // display the 3d chart data no.
            //   Control.KeyDown += new System.Windows.Input.KeyEventHandler(OnKeyDown);
            // display surface chart
            InitChart();
            //TransformChart();
        }