genetic algorithm - make image with transparent polygon

1. mutate parent(add random polygon or delete, change color, alpha) - make child
2. compare with original image
3. if child's fitness is better than parent, child is parent.
4. go to 1

Reference - http://linesandcolors.com/2008/12/10/genetic-programming-evolution-of-mona-lisa/

p.s. : it takes a lot of time to see a good image..