Redraw the render window.

        Args:
            reset_camera: Set to True to reset the camera to a
                pre-determined default for each structure.  Defaults to False.

def redraw(self, reset_camera=False):
        """
        Redraw the render window.

        Args:
            reset_camera: Set to True to reset the camera to a
                pre-determined default for each structure.  Defaults to False.
        """
        self.ren.RemoveAllViewProps()
        self.picker = None
        self.add_picker_fixed()
        self.helptxt_mapper = vtk.vtkTextMapper()
        tprops = self.helptxt_mapper.GetTextProperty()
        tprops.SetFontSize(14)
        tprops.SetFontFamilyToTimes()
        tprops.SetColor(0, 0, 0)

        if self.structure is not None:
            self.set_structure(self.structure, reset_camera)

        self.ren_win.Render()