    # File lib/rvg/rvg.rb, line 232
            def draw
                raise StandardError, "draw not permitted in nested RVG objects" if @nested
                @canvas ||= new_canvas    # allow drawing over existing canvas
                gc = Utility::GraphicContext.new
                add_outermost_primitives(gc)
                pp(self) if ENV['debug_rvg']
                print_gc(gc) if ENV['debug_prim']
                gc.draw(@canvas)
                return @canvas
            end