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<!DOCTYPE html>
<!-- DO NOT EDIT! This test has been generated by /html/canvas/tools/gentest.py. -->
<title>OffscreenCanvas test: 2d.imageData.create2.large</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/html/canvas/resources/canvas-tests.js"></script>

<h1>2d.imageData.create2.large</h1>
<p class="desc">createImageData(sw, sh) works for sizes much larger than the canvas</p>


<script>
var t = async_test("createImageData(sw, sh) works for sizes much larger than the canvas");
var t_pass = t.done.bind(t);
var t_fail = t.step_func(function(reason) {
    throw reason;
});
t.step(function() {

  var canvas = new OffscreenCanvas(100, 50);
  var ctx = canvas.getContext('2d');

  var imgdata = ctx.createImageData(1000, 2000);
  _assertSame(imgdata.data.length, imgdata.width*imgdata.height*4, "imgdata.data.length", "imgdata.width*imgdata.height*4");
  _assert(imgdata.width < imgdata.height, "imgdata.width < imgdata.height");
  _assert(imgdata.width > 0, "imgdata.width > 0");
  var isTransparentBlack = true;
  for (var i = 0; i < imgdata.data.length; i += 7813) // check ~1024 points (assuming normal scaling)
      if (imgdata.data[i] !== 0)
          isTransparentBlack = false;
  _assert(isTransparentBlack, "isTransparentBlack");
  t.done();

});
</script>