composited-canvas-disable-acceleration-pattern.html

<!DOCTYPE html>
<p>
  Regression test for crbug.com/1499539.
  Disables acceleration by using a pattern.
</p>
<canvas id="canvas" width="100" height="100"></canvas>
<script>
if (window.testRunner) {
  testRunner.waitUntilDone();
}
const canvas1 = document.getElementById('canvas');
const ctx1 = canvas1.getContext('2d');

ctx1.fillStyle = 'blue';
ctx1.fillRect(0, 0, 10, 10);

const canvas2 = document.createElement('canvas');
const ctx2 = canvas2.getContext('2d');
ctx2.fillStyle = 'green';
ctx2.fillRect(0, 0, 10, 10);

const img = new Image();
img.onload = function() {
  ctx1.fillStyle = ctx1.createPattern(img, 'repeat');
  ctx1.fillRect(0, 0, 40, 40);
  ctx1.drawImage(canvas2, 20, 0);

  if (window.testRunner) {
    testRunner.notifyDone();
  }
}
img.src = 'resources/pattern.png';
</script>

chromium/third_party/blink/web_tests/fast/canvas/composited-canvas-disable-acceleration-pattern.html