<!DOCTYPE html>
<html>
<head>
<title>This tests ancestor clipping with subpixel positioning.</title>
<style>
.container {
  position: absolute;
  background-color: green; 
  width: 15px; 
  height: 15px;
  transform: translateZ(0);
}

.clippingAncestor { 
  width: 10px;
  height: 10px;
  overflow: hidden;
  border-style: solid;
  border-color: red;
  } 

.jiggle {
  height: 5px;
  width: 5px; 
  position: relative;
  background-color: blue;
  transform: translateZ(0);
}
</style>
</head>
<body>
<script>
var subpixelForContainer = 0;
for (var i = 0; i < 20; ++i) {
  var borderWidth = 2;
  var subpixelForJiggle = -2;
  for (var j = 0; j < 20; ++j) {
    var container = document.createElement("div");
    container.className = "container";
    container.style.left = i * 20 + subpixelForContainer + "px";
    container.style.top = j * 20 + subpixelForContainer + "px";
    document.body.appendChild(container);
    subpixelForContainer += 0.05;

    var clippingAncestor = document.createElement("div");
    clippingAncestor.className = "clippingAncestor";
    clippingAncestor.style.borderWidth = borderWidth + "px";
    container.appendChild(clippingAncestor);
    borderWidth += 0.1;

    var jiggle = document.createElement("div");
    jiggle.className = "jiggle";
    jiggle.style.top = subpixelForJiggle + "px";
    jiggle.style.left = subpixelForJiggle + "px";
    subpixelForJiggle += 0.1;
    clippingAncestor.appendChild(jiggle);
  }
}
</script>
</body>
</html>