canvas中来做元素的旋转移动

 一张 图片，在canvas中 怎么 做 旋转 同时移动，直接上demo先。用chrome才看的到哦亲

-----------------------------我是可爱的源码分割线------------------------------------

 1     var width = 600;
 2     var height = 300;
 3     var imgs = [];
 4 
 5     var X = 74, Y = 74;
 6     var X1=452,Y1=74;
 7     var rotation=0;
 8     var rotation1=0
 9 
10     var regx = 74;
11     var regy = 42;
12     var iwidth = 148;
13     var iheight = 84;
14     
15     var canvas = document.getElementById('myCanvas');
16     var ctx = canvas.getContext('2d');
17 
18     var img = new Image();
19     img.onload = function(){            
20         imgs.push(this);                
21         imgs.push(this);        
22     };
23     img.src = 'buy.png';
24     
25     function loop(){
26         ctx.clearRect(0, 0, width, height);
27         for(var i = 0; i < imgs.length; i++){
28             if (i==0){              
29                 var img = imgs[i];
30                 ctx.save();
31                 rotation += 6;
32                 if( X != 0 || Y != 0 ) ctx.translate( X , Y );
33                 if( rotation % 360 != 0) ctx.rotate( rotation%360 * (Math.PI / 180) );            
34                 if( regx != 0 || regy != 0 ) ctx.translate( -regx, -regy ); 
35                 
36                 X += 6;                    
37                 if (X>=452){
38                    X -= 6;    
39                 }
40                 ctx.drawImage( img , 0, 0 , iwidth,iheight, 0 , 0 , iwidth, iheight);
41                 ctx.restore();
42             }
43             if (i==1){
44                 var img1=imgs[i];
45                 ctx.save();
46                 rotation1 -=15;
47                 
48                 if( X1 != 0 || Y1 != 0 ) ctx.translate( X1 , Y1 );
49                 if( rotation1 % 360 != 0) ctx.rotate( rotation1%360 * (Math.PI / 180) );            
50                 if( regx != 0 || regy != 0 ) ctx.translate( -regx, -regy ); 
51 
52                 X1 -= 6;    
53                 if (X1<=74){
54                   X1 += 6;
55                 }
56                 
57                 ctx.drawImage( img1 , 0, 0,iwidth , iheight,0,0 , iwidth, iheight);
58                 ctx.restore();
59             }
60         };
61     }
62 
63     window.setTimeout(function(){    
64         setInterval(loop, 1000 / 24);
65     },500);/**/