| <!DOCTYPE html> |
| <meta charset=utf-8> |
| <title>Seamlessly updating the playback rate of an animation</title> |
| <link rel="help" |
| href="https://drafts.csswg.org/web-animations-1/#seamlessly-updating-the-playback-rate-of-an-animation"> |
| <script src="/resources/testharness.js"></script> |
| <script src="/resources/testharnessreport.js"></script> |
| <script src="/web-animations/testcommon.js"></script> |
| <script src="testcommon.js"></script> |
| <style> |
| .scroller { |
| overflow: auto; |
| height: 100px; |
| width: 100px; |
| will-change: transform; |
| } |
| |
| .contents { |
| height: 1000px; |
| width: 100%; |
| } |
| </style> |
| <body> |
| <script> |
| 'use strict'; |
| |
| promise_test(async t => { |
| const animation = createScrollLinkedAnimation(t); |
| // Wait for new animation frame which allows the timeline to compute new |
| // current time. |
| await waitForNextFrame(); |
| animation.play(); |
| await animation.ready; |
| |
| animation.currentTime = 500; |
| |
| animation.updatePlaybackRate(0.5); |
| await animation.ready; |
| assert_times_equal(animation.currentTime, 500, |
| 'Reducing the playback rate should not change the current time ' + |
| 'of a playing animation'); |
| |
| animation.updatePlaybackRate(2); |
| await animation.ready; |
| assert_times_equal(animation.currentTime, 500, |
| 'Increasing the playback rate should not change the current time ' + |
| 'of a playing animation'); |
| }, 'Updating the playback rate maintains the current time'); |
| |
| promise_test(async t => { |
| const animation = createScrollLinkedAnimation(t); |
| // Wait for new animation frame which allows the timeline to compute new |
| // current time. |
| await waitForNextFrame(); |
| animation.play(); |
| await animation.ready; |
| |
| assert_false(animation.pending); |
| animation.updatePlaybackRate(2); |
| assert_true(animation.pending); |
| }, 'Updating the playback rate while running makes the animation pending'); |
| |
| promise_test(async t => { |
| const animation = createScrollLinkedAnimation(t); |
| // Wait for new animation frame which allows the timeline to compute new |
| // current time. |
| await waitForNextFrame(); |
| animation.play(); |
| animation.currentTime = 500; |
| assert_true(animation.pending); |
| |
| animation.updatePlaybackRate(0.5); |
| |
| // Check that the hold time is updated as expected |
| assert_times_equal(animation.currentTime, 500); |
| |
| await animation.ready; |
| |
| // As above, check that the currentTime is not calculated by simply |
| // substituting in the updated playbackRate without updating the startTime. |
| assert_times_equal(animation.currentTime, 500, |
| 'Reducing the playback rate should not change the current time ' + |
| 'of a play-pending animation'); |
| }, 'Updating the playback rate on a play-pending animation maintains' |
| + ' the current time'); |
| |
| promise_test(async t => { |
| const animation = createScrollLinkedAnimation(t); |
| // Wait for new animation frame which allows the timeline to compute new |
| // current time. |
| await waitForNextFrame(); |
| animation.play(); |
| animation.currentTime = 500; |
| await animation.ready; |
| |
| animation.pause(); |
| animation.updatePlaybackRate(0.5); |
| |
| assert_times_equal(animation.currentTime, 500); |
| }, 'Updating the playback rate on a pause-pending animation maintains' |
| + ' the current time'); |
| |
| promise_test(async t => { |
| const animation = createScrollLinkedAnimation(t); |
| // Wait for new animation frame which allows the timeline to compute new |
| // current time. |
| await waitForNextFrame(); |
| animation.play(); |
| |
| animation.updatePlaybackRate(2); |
| animation.updatePlaybackRate(3); |
| animation.updatePlaybackRate(4); |
| |
| assert_equals(animation.playbackRate, 1); |
| await animation.ready; |
| |
| assert_equals(animation.playbackRate, 4); |
| }, 'If a pending playback rate is set multiple times, the latest wins'); |
| |
| promise_test(async t => { |
| const animation = createScrollLinkedAnimation(t); |
| // Wait for new animation frame which allows the timeline to compute new |
| // current time. |
| await waitForNextFrame(); |
| animation.play(); |
| animation.cancel(); |
| |
| animation.updatePlaybackRate(2); |
| assert_equals(animation.playbackRate, 2); |
| assert_false(animation.pending); |
| }, 'In the idle state, the playback rate is applied immediately'); |
| |
| promise_test(async t => { |
| const animation = createScrollLinkedAnimation(t); |
| // Wait for new animation frame which allows the timeline to compute new |
| // current time. |
| await waitForNextFrame(); |
| animation.pause(); |
| await animation.ready; |
| |
| animation.updatePlaybackRate(2); |
| assert_equals(animation.playbackRate, 2); |
| assert_false(animation.pending); |
| }, 'In the paused state, the playback rate is applied immediately'); |
| |
| promise_test(async t => { |
| const animation = createScrollLinkedAnimation(t); |
| // Wait for new animation frame which allows the timeline to compute new |
| // current time. |
| await waitForNextFrame(); |
| animation.play(); |
| animation.finish(); |
| assert_time_equals_literal(animation.currentTime, 1000); |
| assert_false(animation.pending); |
| |
| animation.updatePlaybackRate(2); |
| assert_equals(animation.playbackRate, 2); |
| assert_time_equals_literal(animation.currentTime, 1000); |
| assert_false(animation.pending); |
| }, 'Updating the playback rate on a finished animation maintains' |
| + ' the current time'); |
| |
| promise_test(async t => { |
| const animation = createScrollLinkedAnimation(t); |
| // Wait for new animation frame which allows the timeline to compute new |
| // current time. |
| await waitForNextFrame(); |
| animation.play(); |
| animation.finish(); |
| assert_time_equals_literal(animation.currentTime, 1000); |
| assert_false(animation.pending); |
| |
| animation.updatePlaybackRate(0); |
| assert_equals(animation.playbackRate, 0); |
| assert_time_equals_literal(animation.currentTime, 1000); |
| assert_false(animation.pending); |
| }, 'Updating the playback rate to zero on a finished animation maintains' |
| + ' the current time'); |
| |
| </script> |
| </body> |