JS1k: The JavaScript code golfing competition

c.width=w=window.innerWidth;c.height=h=window.innerHeight;c.style.background='#000';var M=Math,rd=M.random,cl=8388607,he,hs=[],hR=20,r=40,k,o,i,j,c,cs=[],l,d;for(i=0;i<60;i++){hs[i]={x:i*50,y:h*rd(),v:{x:rd(),y:rd()},c:'#'+M.floor(cl+rd()*cl).toString(16)};}for(i=0;i<9;i++){cs[i]={x:((i+1)*(w/10)),y:((i%2)+1)*(h/3),b:1};}l=a.createLinearGradient(0,0,0,h);l.addColorStop(0,'#0AE');l.addColorStop(1,'#fff');setInterval(function(){a.globalAlpha=.8;a.fillStyle=l;a.fillRect(0,0,w,h);a.font=hR*1.6+'px Arial';for(i=0;i<hs.length;i++){he=hs[i];for(j=0;j<cs.length;j++){c=cs[j];k=c.x-he.x;o=c.y-he.y;d=k*k+o*o;if(d<(hR+r)*(hR+r)){c.b=1.05;he.v.x+=-k;he.v.y+=-o;}}he.x+=he.v.x=M.max(M.min(he.v.x+rd()*0.4-0.2,4),-4);he.y+=he.v.y=M.max(M.min(he.v.y+0.2,8),-8);he.y=(h+he.y)%h;he.x=(w+he.x)%w;a.fillStyle=he.c;f(he,hR);a.fillStyle='#fff';a.fillText('♥',he.x-hR/2,he.y+hR/2);}for(i=0;i<cs.length;i++){c=cs[i];f(c,r*c.b);c.b=1;}},30);function f(o,r){a.beginPath();a.arc(o.x,o.y,r,0,Math.PI*2,true);a.closePath();a.fill();}

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

c.width = w = window.innerWidth;
c.height = h = window.innerHeight;
c.style.background = '#000';

var ran = Math.random;

var heart,
hearts = [],
hRad=20;
var r = 40;
for(var i =0; i<70; i++){
	hearts.push(
		{x:i*50,
		y:h*Math.random(),
		vel:{
			x:Math.random(),
			y:Math.random()},
			colour:'#'+Math.floor((16777215/2) + Math.random()*(16777215/2)).toString(16)
		}
	);
}
var cir,circles = [];
var i,j;
for(i =0; i<9; i++){
	circles.push({
		x:((i+1)*(w/10)), 
		y:((i%2)+1) * (h/3),b:1
	});
}

var linGrad = a.createLinearGradient(0,0,0,h);  
linGrad.addColorStop(0, '#00ABEB');  
linGrad.addColorStop(1, '#fff');  

setInterval( function() {
  a.globalAlpha = .8;
  a.fillStyle = linGrad;
  a.fillRect(0,0,w,h);
  a.font = hRad*1.6+'px Arial';
  for(i=0; i<hearts.length; i++ ) {
	heart = hearts[i];
	
	//check which cirle the hearts will intersect with and repels it
	for(j=0;j<circles.length;j++){
		cir = circles[j];
		var xDist = cir.x - heart.x;
		var yDist = cir.y - heart.y;
		var dist = (xDist*xDist) + (yDist*yDist);
		
		if(dist < (hRad+r)*(hRad+r)){	//intersection, repel the sphere
			cir.b=1.05;	//used to make the circle throb when it's hit
			heart.vel.x += -xDist;
			heart.vel.y += -yDist;
		}
	}	
	
	//work out the velocity of the heart, apply gravity and move it.
	heart.vel.x = Math.max(Math.min(heart.vel.x + ran()*0.4 -0.2,4),-4);
	heart.vel.y = Math.max(Math.min(heart.vel.y + 0.2,8),-8);
	heart.x += heart.vel.x;
	heart.y += heart.vel.y;
	
	//If the heart goes outside the boundaries, loop it to the other side
	heart.y = heart.y%(h+hRad*2);
	heart.x = (w + heart.x) % w;
	
	//the cirle
    a.fillStyle = heart.colour;	
	a.beginPath();
	a.arc(heart.x, heart.y, hRad, 0, Math.PI*2, true); 
	a.closePath();
	a.fill();
	
	//the heart
	a.fillStyle = '#fff';
	a.fillText('♥', heart.x-hRad/2, heart.y+hRad/2);
  }

  //draw the static circles
  for(i=0;i<circles.length;i++){
	a.fillStyle = '#fff';
	cir = circles[i];
	a.beginPath();
	a.arc(cir.x, cir.y, r*cir.b, 0, Math.PI*2, true); 
	a.closePath();
	a.fill();	
	cir.b=1;
  }
}, 30 );