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<!doctype html>
<html>
<head>
<meta charset="UTF-8"/>
<title>Canvas Test</title>
</head>
<body>
<section>
<div>
<canvas id="canvas" width="400" height="300">
This text is displayed if your browser
does not support HTML5 Canvas.
</canvas>
</div>
<script type="text/javascript">
var canvas;
var ctx;
var x = 200;
var y = 150;
var dx = 2;
var dy = 4;
var WIDTH = 200;
var HEIGHT = 150;
function circle(x,y,r) {
ctx.beginPath();
ctx.arc(x, y, r, 0, Math.PI*2, false);
ctx.fill();
}
function rect(x,y,w,h) {
ctx.beginPath();
ctx.rect(x,y,w,h);
ctx.closePath();
ctx.fill();
}
function clear() {
ctx.clearRect(0, 0, WIDTH, HEIGHT);
}
function init() {
canvas = document.getElementById("canvas");
ctx = canvas.getContext("2d");
return setInterval(draw, 100);
}
function draw() {
clear();
ctx.fillStyle = "#FAF7F8";
rect(0,0,WIDTH,HEIGHT);
ctx.fillStyle = "#444444";
circle(x, y, 20);
if (x + dx > WIDTH || x + dx < 0)
dx = -dx;
if (y + dy > HEIGHT || y + dy < 0)
dy = -dy;
x += dx;
y += dy;
}
init();
</script>
</section>
</body>
</html>
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