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Test Info:
- This WPT test may be referenced by the following Test IDs:
- /html/canvas/offscreen/compositing/2d.composite.globalAlpha.range.worker.html - WPT Dashboard Interop Dashboard
// DO NOT EDIT! This test has been generated by /html/canvas/tools/gentest.py.
// OffscreenCanvas test in a worker:2d.composite.globalAlpha.range
// Description:
// Note:
importScripts("/resources/testharness.js");
importScripts("/html/canvas/resources/canvas-tests.js");
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 canvas = new OffscreenCanvas(100, 50);
var ctx = canvas.getContext('2d');
ctx.globalAlpha = 0.5;
// This may not set it to exactly 0.5 if it is rounded/quantised, so
// remember for future comparisons.
var a = ctx.globalAlpha;
_assertSame(ctx.globalAlpha, a, "ctx.globalAlpha", "a");
ctx.globalAlpha = 1.1;
_assertSame(ctx.globalAlpha, a, "ctx.globalAlpha", "a");
ctx.globalAlpha = -0.1;
_assertSame(ctx.globalAlpha, a, "ctx.globalAlpha", "a");
ctx.globalAlpha = 0;
_assertSame(ctx.globalAlpha, 0, "ctx.globalAlpha", "0");
ctx.globalAlpha = 1;
_assertSame(ctx.globalAlpha, 1, "ctx.globalAlpha", "1");
t.done();
});
done();