2d.drawImage.negativesource.html

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This WPT test may be referenced by the following Test IDs:
- /html/canvas/offscreen/drawing-images-to-the-canvas/2d.drawImage.negativesource.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.drawImage.negativesource</title>

<script src="/resources/testharness.js"></script>

<script src="/resources/testharnessreport.js"></script>

<script src="/html/canvas/resources/canvas-tests.js"></script>

<h1>2d.drawImage.negativesource</h1>

<p class="desc">Negative source width/height represents the correct rectangle</p>

<script>

promise_test(async t => {

  var canvas = new OffscreenCanvas(100, 50);

  var ctx = canvas.getContext('2d');

  ctx.fillStyle = '#f00';

  ctx.fillRect(0, 0, 100, 50);

  const response = await fetch('/images/ggrr-256x256.png');

  const blob = await response.blob();

  const bitmap = await createImageBitmap(blob);

  ctx.drawImage(bitmap, 100, 78, -100, 50, 0, 0, 50, 50);

  ctx.drawImage(bitmap, 100, 128, -100, -50, 50, 0, 50, 50);

  _assertPixelApprox(canvas, 1,1, 0,255,0,255, 2);

  _assertPixelApprox(canvas, 1,48, 0,255,0,255, 2);

  _assertPixelApprox(canvas, 98,1, 0,255,0,255, 2);

  _assertPixelApprox(canvas, 98,48, 0,255,0,255, 2);

  _assertPixelApprox(canvas, 48,1, 0,255,0,255, 2);

  _assertPixelApprox(canvas, 48,48, 0,255,0,255, 2);

  _assertPixelApprox(canvas, 51,1, 0,255,0,255, 2);

  _assertPixelApprox(canvas, 51,48, 0,255,0,255, 2);

  _assertPixelApprox(canvas, 25,25, 0,255,0,255, 2);

  _assertPixelApprox(canvas, 75,25, 0,255,0,255, 2);

}, "Negative source width/height represents the correct rectangle");

</script>