third_party/WebKit/LayoutTests/compositing/layer-creation/should-invoke-deferred-compositing.html

   1 <!DOCTYPE html>
   2
   3 <!-- crbug.com/336676 - layer creation should not accidentally skip requesting
   4      the compositor for a frame to be produced. When there were no other
   5      repaints or layout/style changes, the simple act of adding a layer was not
   6      triggering compositing updates by itself. To recreate this scenario, an
   7      out-of-flow canvas element is added to an empty composited layer. The
   8      actual container layer does not get added to the tree until it realizes
   9      that it receives the canvas content. -->
  10
  11
  12 <html>
  13 <head>
  14 <script src="../../fast/repaint/resources/text-based-repaint.js"></script>
  15 <style>
  16
  17 .composited {
  18   transform: translatez(0);
  19 }
  20
  21 .box {
  22   position: absolute;
  23   z-index: 1;
  24   width: 300px;
  25   height: 300px;
  26   top: 0px;
  27   left: 0px;
  28 }
  29
  30 canvas {
  31   position: absolute;
  32   z-index: 1;
  33   top: 0px;
  34   left: 0px;
  35 }
  36
  37 </style>
  38
  39 <script>
  40   function repaintTest() {
  41     var canvasElement = document.createElement("canvas");
  42     canvasElement.width = 200;
  43     canvasElement.height = 200;
  44     var context = canvasElement.getContext("2d");
  45     context.fillStyle = "green";
  46     context.fillRect(80, 80, 50, 50);
  47     document.getElementById("container").appendChild(canvasElement);
  48   }
  49 </script>
  50 </head>
  51
  52 <body onload="runRepaintAndPixelTest()">
  53   <div id="container" class="composited box"></div>
  54 </body>
  55
  56 </html>