third_party/WebKit/LayoutTests/paint/invalidation/animated-gif-background-offscreen.html

   1 <!doctype HTML>
   2 <body>
   3 <div style="height: 2000px; width: 2000px;">
   4 <div id="targetImage" style="width: 50px; height: 50px">
   5 </div>
   6 <img id="testTarget" style="visibility: hidden">
   7
   8 <script src="../../fast/repaint/resources/text-based-repaint.js"></script>
   9 <script>
  10 window.testIsAsync = true;
  11
  12 // The image should not show a paint invalidation if offscreen if Slimming Paint is on.
  13 // Otherwise it should.
  14
  15 // Steps:
  16 // 1. Load the image
  17 // 2. Move the image offscreen
  18 // 3. Start tracking paint invalidation rects
  19 // 4. Call layoutAndPaintAsyncThen (via runRepaintTest, which does this for us) to draw a frame
  20 // 5. Wait longer than 100ms, so that the timer between the first and second animated GIF
  21 //    frame expires and a paint invalidation is issued on the animated GIF. (100ms is the
  22 //    length of the first frame of the animation in the GIF file.)
  23 // 6. Stop tracking paint invalidation rects (finishRepaintTest does this for us)
  24
  25 // These steps differ from a standard repaint test in that step 3 precedes step 4.
  26 // This is critical because layoutAndPaintAsyncThen may take longer than the 100ms of the timer,
  27 // so we may miss it.
  28
  29 function repaintTest() {
  30   setTimeout(finishRepaintTest, 150);
  31 }
  32
  33 function targetImageOnload() {
  34     window.scrollTo(0, 1000);
  35     if (window.internals)
  36         window.internals.startTrackingRepaints(document);
  37     runRepaintTest();
  38 }
  39
  40 window.onload = function() {
  41     targetImage.style.background = "url(../../fast/backgrounds/resources/red-green-animated.gif)";
  42
  43     // Use a parallel image element as a hack to detect whether the image has loaded, and therefore
  44     // we'll get a frame.
  45     testTarget.onload = targetImageOnload;
  46     testTarget.src = "../../fast/backgrounds/resources/red-green-animated.gif";
  47 }
  48 </script>