JS1k: The JavaScript code golfing competition

var d=200,e=301,h,i,l,m,n,o,p,q,r,s;function v(a,b,c){var f,g,t,u,j,k;q=c;m=a-1.5/c;n=a+1.5/c;o=b+1/c;p=b-1/c;for(b=0;b<e/2;b++)for(a=0;a<e;a++){g=f=0;t=m+a*(n-m)/e;u=o+b*(p-o)/(e/2);j=f*f;k=g*g;for(c=0;j+k<=4&&c<d;c++){g=f*g*2;g+=u;f=j-k;f+=t;j=f*f;k=g*g}if(j+k<=4)r.fillStyle="rgb(0,0,0)";else{h=83885*c%255;i=84142*c%255;l=84399*c%255;r.fillStyle="rgb("+h+","+i+","+l+")"}r.fillRect(a*1,b*1,1,1)}}r=document.getElementById("c"); r.style.cssText="position:absolute;background:transparent;left:0px;top:0px;width:300px;height:150px;";r=r.getContext("2d");document.write("<div id='d' style='position:absolute;background:transparent;left:0px;top:0px;width:300px;height:150px;'></div>");s=document.getElementById("d");s.oncontextmenu=function(a){var b;b=a.pageX;a=a.pageY;xcen=b/e*(n-m)+m;ycen=a/(e/2)*(p-o)+o;zoom=q/2;v(xcen,ycen,zoom);return false};s.ondblclick=function(a){v(a.pageX/e*(n-m)+m,a.pageY/(e/2)*(p-o)+o,q*2);return false}; v(-0.5,0,1);

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

var MaxIters = 200;
var SIZE = 301;
var r,g,b,LEFT,RIGHT,TOP,BOTTOM,ZOOM,canvas,capa;
var sty="position:absolute;background:transparent;left:0px;top:0px;width:300px;height:150px;"

function mandel(xcen, ycen, zoom)
{
  var   x, y, count;
  var zr, zi, cr, ci;
  var rsquared, isquared;
  
  ZOOM = zoom;
  LEFT = xcen - 1.5/zoom;
  RIGHT = xcen + 1.5/zoom;
  TOP = ycen + 1.0/zoom;
  BOTTOM = ycen -1.0/zoom;
  
  for (y = 0; y < SIZE/2; y++)
  {
    for (x = 0; x < SIZE; x++)
    {
      zr = 0.0;
      zi = 0.0;
      cr = LEFT + x * (RIGHT - LEFT) / SIZE;
      ci = TOP + y * (BOTTOM - TOP) / (SIZE/2);
      rsquared = zr * zr;
      isquared = zi * zi;
      for (count = 0; rsquared + isquared <= 4 && count < MaxIters; count++)
      {
          zi = zr * zi * 2.0;
          zi += ci;
          zr = rsquared - isquared;
          zr += cr;
          rsquared = zr * zr;
          isquared = zi * zi;
      }
      if (rsquared + isquared <= 4)
      {
        canvas.fillStyle="rgb(0,0,0)";
      }
      else
      {
        r = (0x147AD * count)%0xFF ;
        g = (0x148AE * count)%0xFF ;
        b = (0x149AF * count)%0xFF ;
        canvas.fillStyle="rgb("+r+","+g+","+b+")";
      }
      canvas.fillRect(x*1, y*1, 1, 1);
    }
    
  }
}
function init()
{
  canvas = document.getElementById("c");
  canvas.style.cssText=sty;
  canvas = canvas.getContext("2d");
  document.write("<div id='d' style='"+sty+"'></div>");
  capa = document.getElementById("d");
  capa.oncontextmenu = zoomOut;
  capa.ondblclick = zoomIn;
  mandel(-0.5, 0.0, 1.0);
}

function zoomIn(e)
{
  var x;
  var y;
  x = e.pageX;
  y = e.pageY;
  var xcen = (x/SIZE)*(RIGHT - LEFT) + LEFT;
  var ycen = (y/(SIZE/2.0))*(BOTTOM-TOP) + TOP;
  var zoom = ZOOM * 2.0;
  
  mandel(xcen, ycen, zoom);
  return false;
}
function zoomOut(e)
{
  var x;
  var y;
  x = e.pageX;
  y = e.pageY;
  xcen = (x/SIZE)*(RIGHT - LEFT) + LEFT;
  ycen = (y/(SIZE/2.0))*(BOTTOM-TOP) + TOP;
  zoom = ZOOM / 2.0;
  
  mandel(xcen, ycen, zoom);
  return false;
}
init();
mandel(-0.5,0.0,1.0);