1283417 - [webvtt] the cue doesn't be rendered immediately when its attributes changes

Status: RESOLVED FIXED

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

Description

[Alastor Wu [:alwu]]

STR.
1. go to http://people.mozilla.org/~alwu/WebVTT/vttExample.html
2. change the value of line and position by pressing button

Expected.
3. the cue's position would be changed correctly 

Actual.
3. the cue doesn't change its position or move to wrong position.

Comment 1

[Alastor Wu [:alwu]]

Quote from spec, [1]

> When a WebVTT cue whose active flag is set has its writing direction, snap-to-lines flag, line, 
> position, size, text alignment, region, or text change value, then the user agent must empty the text
> track cue display state, and then immediately run the text track’s rules for updating the display of 
> WebVTT text tracks."

[1] https://w3c.github.io/webvtt/#webvtt-cue

Comment 2

[Alastor Wu [:alwu]]

FYI, also need to render cues immediately when its css style changes.
https://w3c.github.io/webvtt/#css-extensions

Comment 3

[Anthony Jones (:ajones, :kentuckyfriedtakahe, :k17e)]

Mass change P2 -> P3

Comment 4

[Alastor Wu [:alwu]]

Attachment: Bug 1283417 - part1 : implement function to notify cue's display states changed.

Review commit: https://reviewboard.mozilla.org/r/69242/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/69242/

Comment 5

[Alastor Wu [:alwu]]

Attachment: Bug 1283417 - part2 : notify media element when cue's display states changed.

Review commit: https://reviewboard.mozilla.org/r/69244/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/69244/

Comment 6

[Alastor Wu [:alwu]]

Comment on attachment 8777783 [details]
Bug 1283417 - part1 : implement function to notify cue's display states changed.

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/69242/diff/1-2/

Comment 7

[Alastor Wu [:alwu]]

Comment on attachment 8777784 [details]
Bug 1283417 - part2 : notify media element when cue's display states changed.

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/69244/diff/1-2/

Comment 8

[Alastor Wu [:alwu]]

Comment on attachment 8777783 [details]
Bug 1283417 - part1 : implement function to notify cue's display states changed.

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/69242/diff/2-3/

Comment 9

[Alastor Wu [:alwu]]

Comment on attachment 8777784 [details]
Bug 1283417 - part2 : notify media element when cue's display states changed.

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/69244/diff/2-3/

Comment 10

[Benjamin Chen [:bechen]]

Comment on attachment 8777784 [details]
Bug 1283417 - part2 : notify media element when cue's display states changed.

https://reviewboard.mozilla.org/r/69244/#review67538

::: dom/media/TextTrackCue.h:327
(Diff revision 3)
> +    if (!mHaveStartedWatcher && aTextTrack) {
> +      mHaveStartedWatcher = true;
> +      mWatchManager.Watch(mReset, &TextTrackCue::NotifyDisplayStatesChanged);
> +    }

It is better to UnWatch it if the aTextTrack is null.

Comment 11

[Benjamin Chen [:bechen]]

Comment on attachment 8777783 [details]
Bug 1283417 - part1 : implement function to notify cue's display states changed.

https://reviewboard.mozilla.org/r/69242/#review67540

Comment 12

[Alastor Wu [:alwu]]

Comment on attachment 8777783 [details]
Bug 1283417 - part1 : implement function to notify cue's display states changed.

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/69242/diff/3-4/

Comment 13

[Alastor Wu [:alwu]]

Comment on attachment 8777784 [details]
Bug 1283417 - part2 : notify media element when cue's display states changed.

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/69244/diff/3-4/

Comment 14

[Alastor Wu [:alwu]]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=8f6eac7f74fb

Comment 15

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/00dfeaac1814
part1 : implement function to notify cue's display states changed. r=bechen
https://hg.mozilla.org/integration/autoland/rev/b47abe0917b0
part2 : notify media element when cue's display states changed. r=bechen

Comment 16

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/00dfeaac1814
https://hg.mozilla.org/mozilla-central/rev/b47abe0917b0