st98 · August 29, 2015 14:17
diff --git a/m.html b/m.html
 <!doctype html>
 <html>
  <head>
    <meta charset="utf-8">
    <title>マンデルブロ集合。</title>
    <style>
      canvas {
        display: block;
      }
    </style>
  </head>
  <body>
    <h1>マンデルブロ集合。</h1>
    <canvas id="cv" width="480" height="480"></canvas>
    <script>
    var cv = document.getElementById('cv');
    var ctx = cv.getContext('2d');
    var w = cv.width, h = cv.height;

    var minx = -2.25, maxx = 0.75, miny = -1.5, maxy = 1.5;
    var stepx = (maxx - minx) / w, stepy = (maxy - miny) / h, limit = 100;

    var im = ctx.getImageData(0, 0, w, h);
    var d = im.data;

    for (var cx = 0; cx < w; cx++) {
      for (var cy = 0; cy < h; cy++) {
        var a = minx + stepx * cx;
        var b = maxy - stepy * cy;
        var x = 0, y = 0, t;

        for (var i = 0; i < limit; i++) {
          t = x * x - y * y + a;
          y = 2 * x * y + b;
          x = t;
          if ((x * x + y * y) > 8) break;
        }

        if (i >= limit) {
          i = 0;
        }

        d[4 * (cy * w + cx) + 0] = d[4 * (cy * w + cx) + 1] = d[4 * (cy * w + cx) + 2] = Math.min(Math.floor(i * 255 / 15), 255);
        d[4 * (cy * w + cx) + 3] = 255;
      }
    }
    ctx.putImageData(im, 0, 0);
    </script>
    ソースコード: <a href="https://gist.github.com/st98/b14511aa28b8e3303971">https://gist.github.com/st98/b14511aa28b8e3303971</a>
  </body>
 </html>
	<!doctype html>
	<html>
	<head>
	<meta charset="utf-8">
	<title>マンデルブロ集合。</title>
	<style>
	canvas {
	display: block;
	}
	</style>
	</head>
	<body>
	<h1>マンデルブロ集合。</h1>
	<canvas id="cv" width="480" height="480"></canvas>
	<script>
	var cv = document.getElementById('cv');
	var ctx = cv.getContext('2d');
	var w = cv.width, h = cv.height;

	var minx = -2.25, maxx = 0.75, miny = -1.5, maxy = 1.5;
	var stepx = (maxx - minx) / w, stepy = (maxy - miny) / h, limit = 100;

	var im = ctx.getImageData(0, 0, w, h);
	var d = im.data;

	for (var cx = 0; cx < w; cx++) {
	for (var cy = 0; cy < h; cy++) {
	var a = minx + stepx * cx;
	var b = maxy - stepy * cy;
	var x = 0, y = 0, t;

	for (var i = 0; i < limit; i++) {
	t = x * x - y * y + a;
	y = 2 * x * y + b;
	x = t;
	if ((x * x + y * y) > 8) break;
	}

	if (i >= limit) {
	i = 0;
	}

	d[4 * (cy * w + cx) + 0] = d[4 * (cy * w + cx) + 1] = d[4 * (cy * w + cx) + 2] = Math.min(Math.floor(i * 255 / 15), 255);
	d[4 * (cy * w + cx) + 3] = 255;
	}
	}
	ctx.putImageData(im, 0, 0);
	</script>
	ソースコード: <a href="https://gist.github.com/st98/b14511aa28b8e3303971">https://gist.github.com/st98/b14511aa28b8e3303971</a>
	</body>
	</html>