rotating 2 images in opposite directions

**conor909** · 07-23-2012 10:40 PM

I can't seem to have 2 images rotating in opposite directions within the same Script. Im trying to keep my code really clean, and I am a beginner to Javascript. Can anyone help? here is my code...

Code:

  <script type="text/javascript">
            var cog = new Image();
			var cog2 = new Image();
            
			function init() {
                cog.src = 'images/bigwheel.png';
                setInterval(draw,10);
            }
			
			function init() {
                cog2.src = 'images/smallwheel.png';
                setInterval(draw,10);
            }
			
            var rotation = 0;
            function draw(){
                var ctx = document.getElementById('bigwheelcanvas').getContext('2d');
                ctx.globalCompositeOperation = 'destination-over';
                ctx.save();
                ctx.clearRect(0,0,173,173);
                ctx.translate(86.5,86.5); // to get it in the origin
                rotation +=.1;
                ctx.rotate(rotation*Math.PI/64); //rotate in origin
                ctx.translate(-86.5,-86.5); //put it back
                ctx.drawImage(cog,0,0);
                ctx.restore();
			}
			init();
			
			var rotation = 0;
            function draw(){
                var ctx = document.getElementById('smallwheelcanvas').getContext('2d');
                ctx.globalCompositeOperation = 'destination-over';
                ctx.save();
                ctx.clearRect(0,0,150,150);
                ctx.translate(75,75); // to get it in the origin
                rotation -=.1;
                ctx.rotate(rotation*Math.PI/64); //rotate in origin
                ctx.translate(-75,-75); //put it back
                ctx.drawImage(cog2,0,0);
                ctx.restore();
			}
			init();	

        </script>

HTML

Code:

<div id="bigwheel">
	
    <canvas id="bigwheelcanvas" width="173" height="173"></canvas>

</div><!--bigwheel-->

<div id="smallwheel">
	
  <canvas id="smallwheelcanvas" width="150" height="150"></canvas>

</div><!--smallwheel-->

**vwphillips** · 07-24-2012 05:19 AM

Code:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">

<head>
  <title></title>
</head>

<body>
<div id="bigwheel">

    <canvas id="bigwheelcanvas" width="173" height="173"></canvas>

</div><!--bigwheel-->

<div id="smallwheel">

  <canvas id="smallwheelcanvas" width="150" height="150"></canvas>

</div><!--smallwheel-->
  <script type="text/javascript">
            var cog = new Image();
			var cog2 = new Image();

			function init() {
                cog.src = 'http://www.vicsjavascripts.org.uk/StdImages/Egypt5.jpg';
                draw('bigwheelcanvas',cog,173,173,0,0.1);
            }

			function init2() {
                cog2.src = 'http://www.vicsjavascripts.org.uk/StdImages/Egypt5.jpg';
                draw('smallwheelcanvas',cog2,150,150,0,-0.1);
            }

            function draw(id,img,w,h,cnt,i){
                var ctx = document.getElementById(id).getContext('2d');
                ctx.globalCompositeOperation = 'destination-over';
                ctx.save();
                ctx.clearRect(0,0,w,h);
                ctx.translate(w/2,h/2); // to get it in the origin
                cnt +=i;
                ctx.rotate(cnt*Math.PI/64); //rotate in origin
                ctx.translate(-w/2,-h/2); //put it back
                ctx.drawImage(img,0,0);
                ctx.restore();
                setTimeout(function(){ draw(id,img,w,h,cnt,i); },10);
	     	}

			init();
			init2();

        </script></body>

</html>

Thread: rotating 2 images in opposite directions

Thread Tools

Display

Hybrid View

rotating 2 images in opposite directions

Thread Information

Users Browsing this Thread

Tags for this Thread

Bookmarks

Bookmarks

Posting Permissions