Image noise: Difference between revisions

=={{header|Racket}}==

<lang racket>

#lang racket

(require 2htdp/image 2htdp/universe)

(define black (color 0 0 0 255))

(define white (color 255 255 255 255))

(define-struct world (last fps))

(define (noise w h)

(color-list->bitmap

(for*/list ([x (in-range w)] [y (in-range h)])

(if (zero? (random 2))

black

white))

w h ))

(define (draw w)

(underlay/xy

(noise 320 240) 0 0

(text (number->string (world-fps w)) 64 "Red")))

(define (handle-tick w)

(define cm (current-inexact-milliseconds))

(make-world cm (exact-floor (/ 1000.0 (- cm (world-last w))))))

(big-bang (make-world 1 0)

[on-draw draw]

[on-tick handle-tick (/ 1. 120)])

</lang>