layer-due-to-layer-children-switch.html

<!DOCTYPE html>

<html>
<head>
  <style type="text/css" media="screen">
    body {
      position: relative;
    }
    .parent {
      position: relative;
      width: 200px;
      height: 150px;
      padding: 20px;
      border: 1px solid black;
      transform: translate(0px, 0px);
    }
    
    .child {
      position: relative;
      left: 100px;
      width: 250px;
      height: 100px;
      background-color: green;
    }
    
  </style>
  <script src="../../resources/run-after-layout-and-paint.js"></script>
  <script>
    if (window.testRunner) {
        testRunner.dumpAsText();
        testRunner.waitUntilDone();
    }
    var text = "";
    function showTree(which)
    {
        if (!window.testRunner || !window.internals)
            return;
        text += "\n" + which + " dump layer tree:\n";
        text += internals.layerTreeAsText(document);
        testRunner.setCustomTextOutput(text);
    }

    function doTest()
    {
        showTree("First");
            
        // Put child in compositing mode
        runAfterLayoutAndPaint(function() {
            document.getElementById("child").style.webkitTransform = "perspective(600) translate3D(-50px, 10px, 100px) rotateY(45deg)";
            showTree("Second");
            
            // Take it back out of compositing mode
            runAfterLayoutAndPaint(function() {
                document.getElementById("child").style.webkitTransform = "";
                showTree("Third");
                
                if (window.testRunner)
                    testRunner.notifyDone();
            });
        });
    }

    window.addEventListener('load', doTest, false);
  </script>
</head>

<body>
  
  <!-- Normally we skip making a compositing layer on a parent, even if its children are composited -->
  <!-- But if the parent has a 2D transform it should get a compositing layer -->
  <!-- Should see a green box in perspective. Layer tree should show nested layers-->
  <div id="parent" class="parent">
      This content is in the parent
      <div id="child" class="child">
          Box should switch between perspective and flat
      </div>
  </div>
  
  <pre id="layers">Layer tree goes here in DRT</pre>
</body>
</html>
chromium/third_party/blink/web_tests/compositing/geometry/layer-due-to-layer-children-switch.html
