1412694 - Consider adding a flag similar to isRunningCompositor for throttled animations in out-of-view elements

Status: NEW

(Core :: DOM: Animation, enhancement, P3)

Description

[Hiroyuki Ikezoe (:hiro)]

Or rename isRunningOnCompositor to isThrottled or something?  So that we can easily see that the animations are optimized in devtools.  I am not sure it's useful for web developers, but I am convinced it's useful for use, developers (and contributers).

Comment 1

[Brian Birtles (:birtles, Feb 26~ parental leave)]

Yeah, this would be good because out-of-view animations don't run on the compositor so it's sometimes not clear in DevTools why a certain animation is not running on the compositor. Adding this flag would allow DevTools to provide more meaningful information in this case (perhaps it could just mark the animation as "fully optimized" if *either* it is running on the compositor *or* it is being throttled because it is out of view).

Comment 2

[Hiroyuki Ikezoe (:hiro)]

"fully optimized" sounds good to me. :)

Comment 3

[Hiroyuki Ikezoe (:hiro)]

Attachment: Introduce isFullyThrottled flag

FWIW, here is a patch that I have locally.  I might be misunderstanding what Brian said about 'fully throttled'.   Do'h!  Now I realized the name what Brian said is 'fully optimized'.  Sigh..

Anyway, in my understanding, the 'fully' means that the animation doesn't consume either the main thread or the compositor thread.

Comment 4

[Hiroyuki Ikezoe (:hiro)]

Attachment: Changes for devtools

And this is a quick dirty patch to display a lighting bolt for the fully-throttled animations on devtools.  With this patch I can detect unthrottled animations easily. :)

Comment 5

[Adrian Florinescu [:aflorinescu]]

As per discussion with Daisuke on 04/10 and also for QA verification purposes this bug should also fix the side effect that the icon for fully-optimized/partial optimized is only visible when the animation is playing. (icon not visible when animation is paused or re-winded). 
If a separate bug should be logged for the above, please let me know.