    # File lib/rvg/embellishable.rb, line 356
                def rvg(cols, rows, x=0, y=0, &block)
                    rvg = Magick::RVG.new(cols, rows, &block)
                    begin
                        x, y = Float(x), Float(y)
                    rescue ArgumentError
                        args = [cols, rows, x, y]
                        raise ArgumentError, "at least one argument is not convertable to Float (got #{args.collect {|a| a.class}.join(', ')})"
                    end
                    rvg.corner(x, y)
                    @content << rvg
                    return rvg
                end