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Test Info:
- This WPT test may be referenced by the following Test IDs:
- /web-animations/timing-model/animations/reverse-running-animation.html - WPT Dashboard Interop Dashboard
<!DOCTYPE html>
<html class="reftest-wait">
<meta charset="UTF-8">
<title>reverse running animation</title>
<link rel="match" href="reverse-running-animation-ref.html">
<script src="/common/reftest-wait.js"></script>
<script src="../../testcommon.js"></script>
<style>
#box {
background: green;
height: 40px;
width: 40px;
}
</style>
<body>
<div id="box"></div>
<p id="notes">
This test animates the box color from green to red and reverses the play
direction shortly after the midpoint. If the box remains red, the test
failed.
</p>
</body>
<script>
onload = async function() {
const box = document.getElementById('box');
const duration = 10000;
const anim =
box.animate({ bacground: [ 'green', 'red' ] },
{ duration: duration, easing: 'steps(2, jump-none)' });
anim.currentTime = duration / 2;
anim.ready.then(() => {
const startTime = anim.timeline.currentTime;
waitForAnimationFrames(2).then(() => {
anim.reverse();
anim.ready.then(() => {
const reversalTime = anim.timeline.currentTime;
const forwardPlayingTime = reversalTime - startTime;
const checkIfDone = () => {
if (anim.timeline.currentTime - reversalTime > forwardPlayingTime)
takeScreenshot();
else
requestAnimationFrame(checkIfDone);
};
requestAnimationFrame(checkIfDone);
});
});
});
};
</script>