# File lib/rvg/embellishable.rb, line 48
            def initialize(rx, ry, cx=0, cy=0)
                super()
                rx, ry, cx, cy = Magick::RVG.convert_to_float(rx, ry, cx, cy)
                if rx < 0 || ry < 0
                    raise ArgumentError, "radii must be >= 0 (#{rx}, #{ry} given)"
                end
                @primitive = :ellipse
                # Ellipses are always complete.
                @args = [cx, cy, rx, ry, 0, 360]
            end