1557182 - [webvtt] enable wpt '2_tracks.html' and '3_tracks.html'

Status: RESOLVED FIXED

(Core :: Audio/Video: Playback, task, P3)

Description

[Alastor Wu [:alwu]]

In reference files, we should not use <br> for breaking the line, because <br> would take width as well, which would cause a tiny positioning difference.

Comment 1

[Alastor Wu [:alwu]]

Attachment: Bug 1557182 - part1 : use 'Ahem'.

Using Ahem can help to eliminate the unexpected graphic color difference caused by rendeing pipeline.

In addition, the font style should be set on the inner span, because that is the way how we applied ::cue on cue text.

Comment 2

[Alastor Wu [:alwu]]

Attachment: Bug 1557182 - part2 : do not use <br> to generate line break in reference files.

<br> has 1 app unit width, which would push text 1 app unit left and cause the positioning difference.

We should use <div> to enforce them break line without having extra space in the line box.

Comment 3

[Alastor Wu [:alwu]]

Attachment: Bug 1557182 - part3 : enable wpt '2_tracks.html' and '3_tracks.html'.

Comment 4

[BugBot [:suhaib / :marco/ :calixte]]

Bugbug thinks this bug is a task, but please change it back in case of error.

Comment 5

[Alastor Wu [:alwu]]

3_tracks.html would fail on the Windows on the try server [1], I guess that might be caused by tiny calculation error when we check whether the boxes are overlapped or not. I have added a fuzzy for those checking and am waiting for the result.

[1] https://treeherder.mozilla.org/#/jobs?repo=try&revision=96ab969926e702a74047c8324d4d9f8c599854bb&selectedJob=250690810

Comment 6

[Alastor Wu [:alwu]]

Attachment: Bug 1557182 - part4 : add fuzzy for the boundary comparision.

When the check whether boxes are overlapping or box is placing out side the container boundary, we should use fuzzy for this checking if the difference is small enough to be ignored.

When two boxes just overlapped a little bit (like < 0.01 px), which user can't be aware of it and looks like just placing side by side, we acutally don't need to adjust box position again.

Otherwise, it would result in an obvious space between two boxes which makes it look more weird because the basic moving unit for adjusting boxes is the Bsize of the first line box.

In addition, adding fuzzy can also ensure rendering testing can be more robust, because on some platform the cues would overlap a really tiny amount of pixels and causes box moving up more than our expectation, which result in incorrect rendering comparasion.

Comment 7

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/a2865f286873
part1 : use 'Ahem'. r=heycam
https://hg.mozilla.org/integration/autoland/rev/042a06eeefec
part2 : do not use <br> to generate line break in reference files. r=heycam
https://hg.mozilla.org/integration/autoland/rev/6f3c271dd3a5
part3 : enable wpt '2_tracks.html' and '3_tracks.html'. r=heycam
https://hg.mozilla.org/integration/autoland/rev/3b271a31eb8e
part4 : add fuzzy for the boundary comparision. r=heycam

Comment 8

[Daniel Varga [:dvarga]]

https://hg.mozilla.org/mozilla-central/rev/a2865f286873
https://hg.mozilla.org/mozilla-central/rev/042a06eeefec
https://hg.mozilla.org/mozilla-central/rev/6f3c271dd3a5
https://hg.mozilla.org/mozilla-central/rev/3b271a31eb8e

Comment 9

[Web Platform Test Sync Bot [:wpt-sync] (Matrix: #interop:mozilla.org)]

Created web-platform-tests PR https://github.com/web-platform-tests/wpt/pull/17445 for changes under testing/web-platform/tests

Comment 10

[Web Platform Test Sync Bot [:wpt-sync] (Matrix: #interop:mozilla.org)]

Upstream PR merged