third_party/WebKit/LayoutTests/paint/invalidation/spv2/canvas-resize-no-full-invalidation.html

   1 <!-- Based on fast/repaint/canvas-resize-no-full-invalidation.html -->
   2 <!DOCTYPE html>
   3 <style>
   4 canvas {
   5   position: absolute;
   6   width: 600px;
   7   height: 500px;
   8   top: 50px;
   9   left: 50px;
  10   /* object-fit and object-position make the content of the canvas not affected
  11      window.expectedPaintInvalidationObjects = [
  12          "LayoutHTMLCanvas (positioned) CANVAS id='canvas'",
  13      ];
  14      by the resize in paintInvalidationTest(). */
  15   object-fit: contain;
  16   object-position: 0 0;
  17   background-color: #030;
  18 }
  19 </style>
  20 Tests paint invalidation of canvas when it's resized which doesn't affect its contents. Passes if there is only incremental invalidation for the resized background.
  21 <canvas id="canvas" width="500" height="500"></canvas>
  22
  23 <script src="resources/paint-invalidation-test.js"></script>
  24 <script>
  25      window.expectedPaintInvalidationObjects = [
  26          "LayoutHTMLCanvas (positioned) CANVAS id='canvas'",
  27      ];
  28 function paintInvalidationTest() {
  29   document.getElementById('canvas').style.width = '500px';
  30 }
  31 onload = runPaintInvalidationTest;
  32
  33 var ctx = document.getElementById('canvas').getContext('2d');
  34 ctx.beginPath();
  35 ctx.arc(250, 250, 250, 0, 2 * Math.PI);
  36 ctx.fillStyle = 'green';
  37 ctx.fill();
  38 </script>