HTML and CSS Reference
In-Depth Information
Example 5-3. Moving on a vector
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>CH5EX3: Moving On A Vector</title>
<script src="modernizr-1.6.min.js"></script>
<script type="text/javascript">
window.addEventListener('load', eventWindowLoaded, false);
function eventWindowLoaded() {
canvasApp();
}
function canvasSupport () {
return Modernizr.canvas;
}
function canvasApp() {
if (!canvasSupport()) {
return;
}
var pointImage = new Image();
pointImage.src = "point.png";
function drawScreen () {
context.fillStyle = '#EEEEEE';
context.fillRect(0, 0, theCanvas.width, theCanvas.height);
//Box
context.strokeStyle = '#000000';
context.strokeRect(1, 1, theCanvas.width-2, theCanvas.height-2);
ball.x += xunits;
ball.y += yunits;
//Draw points to illustrate path
points.push({x:ball.x,y:ball.y});
for (var i = 0; i< points.length; i++) {
context.drawImage(pointImage, points[i].x, points[i].y,1,1);
}
context.fillStyle = "#000000";
context.beginPath();
context.arc(ball.x,ball.y,15,0,Math.PI*2,true);
context.closePath();
context.fill();
}
