ren.AddLights(lgt);
ren.AddLight(lgt);
        public void Render()         {	  if (rw != null)	    {	    if (windowSet == 0)              { 	      // set the window id and the active camera              this.setWindow(rw);              cam = ren.GetActiveCamera();	      ren.AddLights(lgt);              lgt.SetPosition(cam.GetPosition());              lgt.SetFocalPoint(cam.GetFocalPoint());              windowSet = 1;              }            // System.out.println("Start Render 2");	    rw.Render();            // System.out.println("Finish Render 2");            }	}