third_party/WebKit/LayoutTests/compositing/overflow/scrolling-neg-z-index-descendants-should-cause-repaint.html

   1 <!DOCTYPE HTML>
   2 <html>
   3 <head>
   4 <script>
   5     if (window.testRunner)
   6         window.testRunner.dumpAsText();
   7
   8     if (window.internals) {
   9         window.internals.settings.setPreferCompositingToLCDTextEnabled(false);
  10     }
  11
  12     function hasScrollbarRepaint(layerTree)
  13     {
  14         return hasScrollbarRepaintHelper(JSON.parse(layerTree));
  15     }
  16
  17     function hasScrollbarRepaintHelper(jsonLayerTree) {
  18         var repaintRects = jsonLayerTree["repaintRects"];
  19         if (repaintRects) {
  20             for (var i = 0; i < repaintRects.length; ++i) {
  21                 var width = repaintRects[i][2];
  22                 var height = repaintRects[i][3];
  23                 if (width == 15 && height == 285)
  24                     return true;
  25             }
  26         }
  27         var children = jsonLayerTree["children"];
  28         if (children) {
  29             for (var i = 0; i < children.length; i++) {
  30                 if (hasScrollbarRepaintHelper(children[i]))
  31                     return true;
  32             }
  33         }
  34         return false;
  35     }
  36
  37     function testRepaint() {
  38         var result = "";
  39         var container = document.getElementById("container");
  40
  41         document.body.offsetTop;
  42
  43         if (window.internals)
  44             window.internals.startTrackingRepaints(document);
  45
  46         container.scrollTop = 100;
  47
  48         if (window.internals) {
  49             if (hasScrollbarRepaint(window.internals.layerTreeAsText(document, internals.LAYER_TREE_INCLUDES_REPAINT_RECTS)))
  50                 result += "PASS repainted when expected\n";
  51             else
  52                 result += "FAIL did not repaint when expected\n";
  53             window.internals.stopTrackingRepaints(document);
  54         }
  55
  56         var pre = document.createElement('pre');
  57         document.body.appendChild(pre);
  58         pre.innerHTML = result;
  59         if (!window.internals)
  60             document.getElementById("description").style.display = "block";
  61     }
  62
  63     window.onload = testRepaint;
  64 </script>
  65 <style>
  66     #container {
  67         width: 100px;
  68         height: 300px;
  69         box-shadow: inset 3px 3px 10px grey;
  70         overflow: auto;
  71         border: 1px black solid;
  72         overflow: scroll;
  73         position: relative;
  74         -webkit-backface-visibility: hidden;
  75     }
  76
  77     #neg-z {
  78         position: relative;
  79         z-index: -1;
  80     }
  81
  82     .scrolled {
  83         width: 50px;
  84         height: 50px;
  85         margin: 10px;
  86         position: relative;
  87         background-color: green;
  88     }
  89
  90     #description {
  91         display: none;
  92     }
  93 </style>
  94 </head>
  95 <body>
  96     <pre id="description">
  97         This test ensures that the logic for ensuring that we don't repaint when
  98         scrolling composited layers works correctly in the face of neg z-order
  99         descendants.
 100     </pre>
 101     <div id="container">
 102         <div id="neg-z">
 103             <div class="scrolled"></div>
 104             <div class="scrolled"></div>
 105             <div class="scrolled"></div>
 106             <div class="scrolled"></div>
 107             <div class="scrolled"></div>
 108             <div class="scrolled"></div>
 109             <div class="scrolled"></div>
 110         </div>
 111     </div>
 112 </body>
 113 </html>