JS1k: The JavaScript code golfing competition

for(_='c.Zthj);z++)~;i~H.yGtG1K&&(J+=OMaj.NO.3*NR,y:2}QyGV*(U.xDtD2C999BZline`Zfill_),^ps[^`To(]Gs=[]{x:1dr=!yD00=0;for(;ii<5Style="tD1ZbeginPaj(^ZmoveTo(Zstrokea.widj-0]D+/2,]Ds.lengj;:1*pc[i]	y.olde.ps.push({,y:1},1.5var x~{",_()^_
1,pc=[0Q,0Q],p,ii<4Hpx	D,y	G}zaHap1:i%4],p2:(i+1)%4+(i>3)],l:i>3?180:1+50Ui%2==0)}zs,o=5,lo=oHoO50UNrandom()-.5^sx1:2*i,y1:lo,x2:2Ui+1^y2:o,n:Natan2(o-lo,2)-1.57}^lo=o;!function i(){=;ss<5;s~{xx<pp=.B5U(y=x])D-(X||)^o=.BUV-(Y||V)zX=,Y=V,Op,VOo+.3,x>1Jarc(V,30,0,2*NPI
blackzll<sl~{t=ss[l];>&&<C&&V>K+(tG2-K)U(-)/(C-))-30JRcos(t.n^VRsin(t.n)^x||s||(KCtG2^#0a0",`Widj=30,(CBB
#740)}}xx<ay,e=as[x],r=1D-2D,h=1G-2G,d=Nhypot(r,h^n=-rUy=(e.l-d)/d/2^f=-h*y;1D-=n,1G-=f,2DOn,2GOf}}00112233]G
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-^-`B-DUVQRNOJKGH~zjZ]/.exec(_);)with(_.split(G))_=join(shift());eval(_)

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

//Before minifying and RegPacking

var dr = false;

var pc = [{x: 10, y: 1}, {x: 11.5, y: 1}, {x: 11.5, y: 2}, {x: 10, y: 2}];
var ps = [];
for (var i = 0; i < 4; i++)
  ps.push({x: pc[i].x * 100, y: pc[i].y * 100});
var as = [];
for (var i = 0; i < 5; i++)
  as.push({p1: ps[i % 4], p2: ps[(i + 1) % 4 + (i > 3)], l: i > 3 ? 180 : 100 + (i % 2 == 0) * 50});

var ss = [];
var o = 500;
var lo = o;
for (var i = 0; i < 500; i++) {
  o += (Math.random()  - 0.5) * 50;
  ss.push({x1: i * 200, y1: lo, x2: (i + 1) * 200, y2: o, n: Math.atan2(o - lo, 200) - 1.57});
  lo = o;
}

(function l() {
  a.width = a.width;
  
  for (var t = 0; t < 5; t++) {
    for (var i = 0; i < ps.length; i++) {
      var p = ps[i];
      var vx = (p.x - (p.oldX || p.x)) * 0.9995;
      var vy = (p.y - (p.oldY || p.y)) * 0.999;
      p.oldX = p.x;
      p.oldY = p.y;

      p.x += vx;
      p.y += vy + .003;
      
      if (i > 1) {
        c.beginPath();
        c.arc(p.x - ps[0].x + a.width / 2, p.y, 30, 0, Math.PI * 2);
        c.fillStyle = "black";
        c.fill();
      }

      for (var j = 0; j < ss.length; j++) {
        var s = ss[j];
        if (p.x > s.x1 && p.x < s.x2 && p.y > s.y1 + (s.y2 - s.y1) * ((p.x - s.x1) / (s.x2 - s.x1)) - 30) {
          p.x += Math.cos(s.n) * .3;
          p.y += Math.sin(s.n) * .3;
        }
        if (!i && !t) {
          c.beginPath();
          c.moveTo(s.x1 - ps[0].x + a.width / 2, s.y1);
          c.lineTo(s.x2 - ps[0].x + a.width / 2, s.y2);
          c.strokeStyle = "#0a0";
          c.lineWidth = 30;
          c.stroke();
          c.lineTo(s.x2 - ps[0].x + a.width / 2, 999);
          c.lineTo(s.x1 - ps[0].x + a.width / 2, 999);
          c.fillStyle = "#740";
          c.fill();
        }
      }
    }

    for (var i = 0; i < as.length; i++) {
      var w = as[i];
      var x = w.p1.x - w.p2.x;
      var y = w.p1.y - w.p2.y;
      var d = Math.hypot(x, y);
      var p = (w.l - d) / d / 2;
      var oX = -x * p;
      var oY = -y * p;
      w.p1.x -= oX, w.p1.y -= oY;
      w.p2.x += oX, w.p2.y += oY;
    }
  }
  
  c.beginPath();
  c.moveTo(ps[0].x - ps[0].x + a.width / 2, ps[0].y);
  c.lineTo(ps[1].x - ps[0].x + a.width / 2, ps[1].y);
  c.lineTo(ps[2].x - ps[0].x + a.width / 2, ps[2].y);
  c.lineTo(ps[3].x - ps[0].x + a.width / 2, ps[3].y);
  c.fillStyle = "red";
  c.fill();
  
  if (dr)
    ps[2].x += .1;
  dr = false;
  
  requestAnimationFrame(l);
})();

d.addEventListener("keypress", () => dr = true);