class DrawClippingPlanesConduit : Rhino.Display.DisplayConduit
    {
        private readonly ClipGumballBox d_box;
        private readonly Point3d[] d_corners;
        private readonly Point3d d_center;
        private readonly Point3d XplusCenter;
        private readonly Vector3d XplusVec;
        private readonly Point3d XminusCenter;
        private readonly Vector3d XminusVec;
        private readonly BoundingBox m_bbox;

        public DrawClippingPlanesConduit(ClipGumballBox box)
        {
            d_box = box;
            //edge_lines = d_box.BoundingBox.GetEdges();
            m_bbox = d_box.box.BoundingBox;
            d_corners = d_box.box.GetCorners();
            d_center = d_box.Center;

            Plane planeXplus = new Plane(d_corners[2], d_corners[1], d_corners[6]);
            XplusCenter = planeXplus.ClosestPoint(d_center);
            XplusVec = new Vector3d(d_center - XplusCenter);

            Plane planeXminus = new Plane(d_corners[0], d_corners[3], d_corners[4]);
            XminusCenter = planeXminus.ClosestPoint(d_center);
            XminusVec = new Vector3d(d_center - XminusCenter);


        }

        protected override void CalculateBoundingBox(CalculateBoundingBoxEventArgs e)
        {
            base.CalculateBoundingBox(e);
            e.IncludeBoundingBox(m_bbox);
        }

        protected override void PreDrawObjects(DrawEventArgs e)
        {
            base.PreDrawObjects(e);
            e.Display.AddClippingPlane(XplusCenter, XplusVec);
            e.Display.AddClippingPlane(XminusCenter, XminusVec);
            
            
        }

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    public class ClippingBox : Rhino.Commands.TransformCommand
    {
        public Box basebox;
        static DrawClippingPlanesConduit m_draw_clipping_planes;
        
	protected override Result RunCommand(RhinoDoc doc, RunMode mode)
        {
	///
	to do program here
	///
	
	m_draw_clipping_planes = new DrawClippingPlanesConduit(base_box);
        m_draw_clipping_planes.Enabled = true;