JS1k: The JavaScript code golfing competition

window.onload=function(){var d=[],m=0,n=0,h=6,j,k;j=c.width=window.innerWidth;k=c.height=window.innerHeight;for(var r=j/2-275,s=k/2-110,e=1;20>=e;e++)for(var l=1;50>=l;l++){var p=11*l+r,q=11*e+s;d.push({x:p,y:q,b:p,c:q,d:5,a:0})}c.onmousemove=function(b){m=b.pageX;n=b.pageY};c.onmousedown=function(){h=24};c.onmouseup=function(){h=6};window.setInterval(function(){for(var b in d){var f=d[b].x-m,e=d[b].y-n,g=Math.sqrt(f*f+e*e),f=Math.atan2(e,f);v1o=d[b].x-d[b].b;v2o=d[b].y-d[b].c;vDo=Math.sqrt(v1o*v1o+ v2o*v2o);vAo=Math.atan2(v2o,v1o)+0.78554;200>g?(d[b].x+=Math.cos(f)*(20*h/g),d[b].y+=Math.sin(f)*(20*h/g)):(d[b].x-=Math.cos(vAo)/(20/vDo),d[b].y-=Math.sin(vAo)/(20/vDo));g=Math.round(128*(vDo/200));d[b].a="rgba(0,"+(0+g)+","+(128-g)+",1)"}a.fillStyle="#112211";a.fillRect(0,0,j,k);a.save();a.globalCompositeOperation="lighter";for(b=0;b<d.length;b++)a.fillStyle=d[b].a,a.fillRect(d[b].x,d[b].y,12,12);a.restore()},33)};

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				vDo = Math.sqrt(v1o*v1o + v2o*v2o),
				vAo = Math.atan2(v2o, v1o) + 0.78554;
					
			if(vDm < 200){
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			var col = Math.round((vDo/200)*128);
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