ANTON072
2/3/2015 - 3:28 PM

らせん http://bl.ocks.org/ANTON072/raw/cd79dc33fff6bd0a2070/

``````<!doctype html>
<html lang="en">
<meta charset="UTF-8">
<title>Document</title>
<style>
* {
margin: 0;
}1
</style>
<script src="https://code.createjs.com/createjs-2014.12.12.min.js"></script>
<body>

<canvas id="canvas"></canvas>

<script>

var canvas = document.getElementById('canvas');
canvas.width = window.innerWidth;
canvas.height = window.innerHeight;

var stage = new createjs.Stage(canvas);
var myShape = new createjs.Shape();

var a = 1.14; // 係数
var N = 100; // 周回数
var Loop = N * 100; // 繰り返しの回数
var T = ( 2 * Math.PI ) / 120; // 1ステップの偏角
var LR = true;

function draw(tx, ty) {
var gr = myShape.graphics;

gr.beginStroke(0x00FF99);

R = Math.pow(a, T);
X1 = R * Math.cos(T);
if (LR) {
Math.abs(X1)
}
else {
X1 = X1 * -1
}
Y1 = (R * Math.sin(T)) * -1;

for (i = 2; i < Loop + 1; i++) {
R = Math.pow(a, (T * i));
X1 = R * Math.cos(T * i) + tx;
if (LR) {
Math.abs(X1)
}
else {
X1 = X1 * -1
}
Y1 = (R * Math.sin(T * i)) * -1 + ty;
gr.lineTo(X1, Y1);
}
}

draw(canvas.width / 2 - 100, canvas.height / 2);
draw(canvas.width / 2 + 100, canvas.height / 2 - 100);
draw(canvas.width / 2 + 300, canvas.height / 2);

createjs.Ticker.setFPS(60);