Mandelbrot fractal in console

mandelbrot.rb

#! /bin/ruby
#
require 'complex'

class Mandelbrot
    def initialize(bailout=10, iterations=100)
        @bailout, @iterations = bailout, iterations
    end

    def mandelbrot(x, y)
        c = Complex(x, y)
        z = 0
        @iterations.times do |i|
            z = z**2 + c
            return false if z.abs > @bailout
        end
        return true
    end

    def render(x_size=76, y_size=30, inside_set="*", outside_set=" ")
        0.upto(y_size) do |y|
            0.upto(x_size) do |x|
                scaled_x = -2 + (3 * x / x_size.to_f)
                scaled_y = -2 + (3 * y / y_size.to_f)
                print mandelbrot(scaled_x, scaled_y) ? inside_set : outside_set
            end
            puts
        end
    end
end

Mandelbrot.new.render()