programmering:barnsley1-js-code

<!DOCTYPE html>
<HTML>
<BODY>
<canvas id="canvas" width="640" height="480">Your browser does not support the HTML5 canvas tag.</canvas>
<script>
  var c = document.getElementById("canvas");
  var ctx = c.getContext("2d");
  var imgData=ctx.getImageData(0,0,c.width,c.height);

  function rand(n) {
    return Math.floor((Math.random()*n));
  }

  function drawPixel (x, y, r, g, b, a) {
	var index = (x + y * 640) * 4;
	imgData.data[index + 0] = r;
	imgData.data[index + 1] = g;
	imgData.data[index + 2] = b;
	imgData.data[index + 3] = a;
  }

  function updateCanvas() {
          ctx.putImageData(imgData, 0, 0);
  }

  function draw() {
      while (count<100) {
	  count++;
	  var choose=rand(100);
	  if (choose<2) {
		    x=0;
		    y=0.16*y;
	  }
	  if (choose>=2 && choose<86) {
		    x_new=0.85*x+0.04*y;
		    y=-0.04*x+0.85*y+1.6;
		    x=x_new;
	  }
	  if (choose>=86 && choose<93) {
		    x_new=0.2*x-0.26*y;
		    y=0.23*x+0.22*y+1.6;
		    x=x_new;
	  }
	  if (choose>=93) {
		    x_new=-0.15*x+0.28*y;
		    y=0.26*x+0.25*y+0.44;
		    x=x_new;
	  }
	  drawPixel(Math.floor((x+2.2)*100),Math.floor(y*48),0,0,0,255);
	}
  }

  var x=0;
  var y=0;
  var count;

  for (var j=0; j<500; j++) {
      count=0;
      draw();
      updateCanvas();
  }
  console.log("done");
</script>

</BODY>
</HTML>