W3C home > Mailing lists > Public > public-web-perf@w3.org > December 2012

Standardizing animationStartTime (was RE: [minutes] 2012-10-10 Web Performance WG Teleconference #84)

From: Jatinder Mann <jmann@microsoft.com>
Date: Wed, 5 Dec 2012 19:56:21 +0000
To: "'public-web-perf@w3.org'" <public-web-perf@w3.org>, Robert O'Callahan <roc@ocallahan.org>, "Boris Zbarsky (bzbarsky@mit.edu)" <bzbarsky@mit.edu>, "James Robinson (jamesr@google.com)" <jamesr@google.com>
Message-ID: <dc2dd3a645b44e4a8ceca58d6e3a7076@BY2PR03MB074.namprd03.prod.outlook.com>
I wanted to close on the discussion of standardizing window.animationStartTime in the requestAnimationFrame spec, especially considering this is the only remaining Last Call issue. For context, we had last discussed this topic on this thread: http://lists.w3.org/Archives/Public/public-web-perf/2012Oct/0044.html.



This attribute would allow developers to synchronize animations together using a high resolution timestamp, including script based and CSS based animations. Even for just synchronizing between script based animations, this would mean calling this attribute instead of having to store the callback parameter value of the requestAnimationFrame function in a global on every rAF callback.



As a part of the W3C Workshop on Performance survey, we found that developers were interested in seeing this attribute standardized.



As for the issue of CSS/SMIL events, Philippe had outreached to the CSS WG and they are interested in not firing transitions/animations events in background tabs. I don't think we should block standardizing animationStartTime on that discussion.



Considering Firefox has supported a prefixed windows.mozAnimationStartTime since Firefox 4, I would like to hear Robert's take on whether we should standardize this attribute as well.



Thanks,

Jatinder
Received on Wednesday, 5 December 2012 19:58:25 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 6 January 2015 21:04:33 UTC