<!DOCTYPE html>
<title>Basic use of Worklet Animation</title>
<link rel="help" href="https://drafts.css-houdini.org/css-animationworklet/">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/web-animations/testcommon.js"></script>
<script src="common.js"></script>
<div id="target"></div>
<script>
promise_test(async t => {
await registerConstantLocalTimeAnimator(500);
const effect = new KeyframeEffect(target, [{ opacity: 0 }], { duration: 1000 });
const animation = new WorkletAnimation('constant_time', effect);
animation.play();
// wait until local times are synced back to the main thread.
await waitForAnimationFrameWithCondition(_ => {
return getComputedStyle(target).opacity != '1';
});
assert_equals(getComputedStyle(target).opacity, "0.5");
animation.cancel();
}, "A running worklet animation should output values at specified local time.");
promise_test(async t => {
await registerConstantLocalTimeAnimator(500);
const effect = new KeyframeEffect(target, [{ opacity: 0 }], { duration: 1000 });
const animation = new WorkletAnimation('constant_time', effect);
animation.play();
await waitForAnimationFrameWithCondition(_=> {
return animation.playState == "running"
});
const prevCurrentTime = animation.currentTime;
animation.play();
assert_equals(animation.playState, "running");
assert_equals(animation.currentTime, prevCurrentTime)
animation.cancel();
}, "Playing a running animation should be a no-op.");
</script>