html, body {

    width: 100%;

    height: 100%;

    margin: 0;

    padding: 0;

}

button {

    margin: 10px 0 0 10px;

}

#container {

    position: absolute;

    width: 100%;

    top: 40px;

    bottom: 0;

}

stage = acgraph.create("container");

​

var start;

var finish;

​

stage.listen("renderstart", function() {

  start = (new Date()).getTime();

});

​

// render rectangles

function render(){

​

  document.getElementById("renderButton")

  .style.visibility = "hidden";

​

  start = (new Date()).getTime();

​

  for (var i = 0; i < 500; i++) {

    var left = Math.random() * 300;

    var qwer = Math.random() * 300;

    var rect = stage.rect(left, qwer, 10, 10);

    rect.fill('green');

  }

​

  finish = (new Date()).getTime();

​

  var labelBg = stage.rect();

  var label = stage.text(130, 130);

  label.text((finish - start) + "ms");

  var labelBounds = label.getBounds();

​

  labelBg

    .setX((labelBounds.left)-20)

    .setY((labelBounds.top)+20)

    .setWidth(labelBounds.width+40)

    .setHeight(labelBounds.height-40)

    .fill("#fff")

    .stroke("#000")

    .cursor("pointer");

  label.zIndex(1000000);

  label.disablePointerEvents(true);

  labelBg.zIndex(1000000);

};