mozilla-release/testing/web-platform/tests/offscreen-canvas/fill-and-stroke-styles/2d.gradient.interpolate.colouralpha.html

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

<h1>2d.gradient.interpolate.colouralpha</h1>
<p class="desc"></p>


<script>
var t = async_test("");
var t_pass = t.done.bind(t);
var t_fail = t.step_func(function(reason) {
    throw reason;
});
t.step(function() {

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

var g = ctx.createLinearGradient(0, 0, 100, 0);
g.addColorStop(0, 'rgba(255,255,0, 0)');
g.addColorStop(1, 'rgba(0,0,255, 1)');
ctx.fillStyle = g;
ctx.fillRect(0, 0, 100, 50);
_assertPixelApprox(offscreenCanvas, 25,25, 190,190,65,65, "25,25", "190,190,65,65", 3);
_assertPixelApprox(offscreenCanvas, 50,25, 126,126,128,128, "50,25", "126,126,128,128", 3);
_assertPixelApprox(offscreenCanvas, 75,25, 62,62,192,192, "75,25", "62,62,192,192", 3);
t.done();

});
</script>