Psychedelic Animation

canvasanimation

ClojureScript re-implementation of a js1k.com runner up, originally by Piotr Stosur: "Animated fractal shapes (mainly rotating spirals) similar to CEVs after taking psychedelic/dissociative drugs. :P Based on copying previous frame into 4 smaller fragments (once per frame, no other kind of iterations) so it's much faster than per-pixel fractal generators." - see: http://js1k.com/2013-spring/demo/1431

5 May 2013 by rm-hull

rm-hull/5522065

psychedelic-animation.cljs

; rewritten in Clojurescript from javascript (originally by Piotr Stosur: http://js1k.com/2013-spring/demo/1431)

(ns psychedelic-animation.demo
  (:use [enchilada :only [canvas svg ctx]]
        [jayq.core :only [show hide]]
        [monet.core :only [animation-frame]]
        [monet.canvas :only [fill-style fill-rect draw-image rotate translate]]))

(show canvas)
(hide svg)

(defn draw-frame! [img v t]
  (let [w (+ 600 (* (Math/sin t) 100))
        r (Math/floor (* (Math/sin (* t 3)) 255))
        g (Math/floor (* (Math/sin (* t 5)) 255))
        b (Math/floor (* (Math/sin (* t 7)) 255))]
    (->
      ctx
      (fill-style "rgba(0,0,0,0.005)")
      (fill-rect { :x 0 :y 0 :w w :h w })
      (fill-rect { :x w :y w :w w :h w })
      (fill-style (str "rgba(" r "," g "," b ",0.1)"))
      (fill-rect { :x w :y 0 :w w :h w })
      (fill-rect { :x 0 :y w :w w :h w })
      (draw-image img { :x 0 :y w :w w :h w })
      (draw-image img { :x w :y w :w w :h w })
      (draw-image img { :x w :y 0 :w w :h w })
      (draw-image img { :x 0 :y 0 :w w :h w })
      (translate v v)
      (rotate (* 0.01 (Math/abs (Math/sin t))))
      (translate (- v) (- v)))))

(defn animate [img v]
  (letfn [(loop [t]
            (fn []
              (animation-frame (loop (+ t 0.01))
              (draw-frame! img v t))))]
    ((loop 0))))
      
(animate (.get canvas 0) 450)