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Test Info:
- This WPT test may be referenced by the following Test IDs:
- /html/canvas/offscreen/compositing/2d.composite.globalAlpha.image.html - WPT Dashboard Interop Dashboard
<!DOCTYPE html>
<!-- DO NOT EDIT! This test has been generated by /html/canvas/tools/gentest.py. -->
<meta charset="UTF-8">
<title>OffscreenCanvas test: 2d.composite.globalAlpha.image</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/html/canvas/resources/canvas-tests.js"></script>
<h1>2d.composite.globalAlpha.image</h1>
<p class="desc"></p>
<script>
promise_test(async t => {
var canvas = new OffscreenCanvas(100, 50);
var ctx = canvas.getContext('2d');
ctx.fillStyle = '#0f0';
ctx.fillRect(0, 0, 100, 50);
// Avoiding any potential alpha = 0 optimisations.
ctx.globalAlpha = 0.01;
const response = await fetch('/images/red.png');
const blob = await response.blob();
const bitmap = await createImageBitmap(blob);
ctx.drawImage(bitmap, 0, 0);
_assertPixelApprox(canvas, 50,25, 2,253,0,255, 2);
}, "");
</script>