cool racket graphics

stars.rkt

#lang racket

(require 2htdp/image)
(require 2htdp/universe)

(define (polygons n)
  (let* ([random-color (lambda () (color (random 255) (random 255) (random 255)))]
         [random-polygon (lambda (x) (star-polygon (* (add1 x) 30) (random 12 16) 11 'solid (random-color)))]
         [polygons-list (build-list n random-polygon)]
         [background (square (* 150 n) 'solid (random-color))])
    (foldr overlay background polygons-list)))
  
(big-bang 5
  [name "Stars"]
  [to-draw polygons]
  [on-tick identity 0.5])