2d.imageData.object.clamp.html

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This WPT test may be referenced by the following Test IDs:
- /html/canvas/element/pixel-manipulation/2d.imageData.object.clamp.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>Canvas test: 2d.imageData.object.clamp</title>

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

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

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

<link rel="stylesheet" href="/html/canvas/resources/canvas-tests.css">

<body class="show_output">

<h1>2d.imageData.object.clamp</h1>

<p class="desc">ImageData.data clamps numbers to [0, 255]</p>

<p class="output">Actual output:</p>

<canvas id="c" class="output" width="100" height="50"><p class="fallback">FAIL (fallback content)</p></canvas>

<ul id="d"></ul>

<script>

var t = async_test("ImageData.data clamps numbers to [0, 255]");

_addTest(function(canvas, ctx) {

  var imgdata = ctx.getImageData(0, 0, 10, 10);

  imgdata.data[0] = 100;

  imgdata.data[0] = 300;

  _assertSame(imgdata.data[0], 255, "imgdata.data[\""+(0)+"\"]", "255");

  imgdata.data[0] = 100;

  imgdata.data[0] = -100;

  _assertSame(imgdata.data[0], 0, "imgdata.data[\""+(0)+"\"]", "0");

  imgdata.data[0] = 100;

  imgdata.data[0] = 200+Math.pow(2, 32);

  _assertSame(imgdata.data[0], 255, "imgdata.data[\""+(0)+"\"]", "255");

  imgdata.data[0] = 100;

  imgdata.data[0] = -200-Math.pow(2, 32);

  _assertSame(imgdata.data[0], 0, "imgdata.data[\""+(0)+"\"]", "0");

  imgdata.data[0] = 100;

  imgdata.data[0] = Math.pow(10, 39);

  _assertSame(imgdata.data[0], 255, "imgdata.data[\""+(0)+"\"]", "255");

  imgdata.data[0] = 100;

  imgdata.data[0] = -Math.pow(10, 39);

  _assertSame(imgdata.data[0], 0, "imgdata.data[\""+(0)+"\"]", "0");

  imgdata.data[0] = 100;

  imgdata.data[0] = -Infinity;

  _assertSame(imgdata.data[0], 0, "imgdata.data[\""+(0)+"\"]", "0");

  imgdata.data[0] = 100;

  imgdata.data[0] = Infinity;

  _assertSame(imgdata.data[0], 255, "imgdata.data[\""+(0)+"\"]", "255");

});

</script>