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Test Info: Warnings
- This test has a WPT meta file that expects 1 subtest issues.
- This WPT test may be referenced by the following Test IDs:
- /css/css-properties-values-api/animation/registered-var-to-registered-animating.html - WPT Dashboard Interop Dashboard
<!DOCTYPE html>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<style>
#target {
--static: 100;
}
</style>
<div id="target"></div>
<script>
setup(() => {
for (let name of ['--test', '--static', '--animated']) {
CSS.registerProperty({
name,
syntax: '<number>',
initialValue: '0',
inherits: false,
});
}
});
test(() => {
// --test is animating from a static value to an animated value resulting in it changing quadratically.
let animation = target.animate({'--test': ['var(--static)', 'var(--animated)']}, 100);
let referencedAnimation = target.animate({'--animated': ['200', '300']}, 100);
referencedAnimation.currentTime = 25;
{
animation.currentTime = 25;
// lerp(100, lerp(200, 300, 25%), 25%) == 0.75*100 + 0.25*(0.75*200 + 0.25*300) == 131.25
assert_equals(getComputedStyle(target).getPropertyValue('--test'), '131.25', 'target at 25%, to at 25%');
animation.currentTime = 75;
// lerp(100, lerp(200, 300, 25%), 75%) == 0.25*100 + 0.75*(0.75*200 + 0.25*300) == 193.75
assert_equals(getComputedStyle(target).getPropertyValue('--test'), '193.75', 'target at 75%, to at 25%');
}
referencedAnimation.currentTime = 75;
{
animation.currentTime = 25;
// lerp(100, lerp(200, 300, 75%), 25%) == 0.75*100 + 0.25*(0.25*200 + 0.75*300) == 143.75
assert_equals(getComputedStyle(target).getPropertyValue('--test'), '143.75', 'target at 25%, to at 25%');
animation.currentTime = 75;
// lerp(100, lerp(200, 300, 75%), 75%) == 0.25*100 + 0.75*(0.25*200 + 0.75*300) == 231.25
assert_equals(getComputedStyle(target).getPropertyValue('--test'), '231.25', 'target at 75%, to at 25%');
}
}, 'Animated registered custom properties can var() reference other animated registered custom properties across separate Animations.');
</script>