Re: [cssom-view][css3-animations] Sync events with requestAnimationFrame






-----Original Message-----
From: Simon Pieters <simonp@opera.com>
Date: Tuesday, December 9, 2014 at 2:00 AM
To: W3C www-style mailing list <www-style@w3.org>, Adobe 
<galineau@adobe.com>
Subject: Re: [cssom-view][css3-animations] Sync events with 
requestAnimationFrame

>On Tue, 09 Dec 2014 00:26:54 +0100, Sylvain Galineau <galineau@adobe.com> 
> 
>wrote:
>
>>
>> -----Original Message-----
>> From: Simon Pieters <simonp@opera.com>
>> Date: Wednesday, November 19, 2014 at 2:28 PM
>> To: www-style list <www-style@w3.org>
>> Subject: [cssom-view][css3-animations] Sync events with
>> requestAnimationFrame
>> Resent-From: <www-style@w3.org>
>> Resent-Date: Wednesday, November 19, 2014 at 2:28 PM
>>
>>> There is an open bug on cssom-view to sync resize/scroll events and
>>> MediaQueryList with requestAnimationFrame.
>>>
>>> https://www.w3.org/Bugs/Public/show_bug.cgi?id=26516

>>>
>>> HTML has now changed its "update the rendering" step in the event loop 
>>> 
>>> to
>>>
>>> call hooks in CSSOM View that are not yet defined, but I plan to 
>>>define.
>>>
>>> See https://html5.org/r/8849

>>> 
>>>https://html.spec.whatwg.org/multipage/webappapis.html#processing-model-

>>>9
>>>
>>> HTML also calls a hook for "run CSS animations and send events", so
>>> presumably the CSS Animations spec should define that.
>>>
>>> --
>>> Simon Pieters
>>> Opera Software
>>>
>>
>>
>> I am not sure what it is css-animations needs to define here, if  
>> anything.
>> As far as I can tell, HTML is really defining the value of the animation
>> events’ timeStamp property.
>
>No, it isn't.
>
>> What am I missing?
>
>HTML is invoking a hook that does not yet exist.
>
>[[
>For each fully active Document in docs, run CSS animations and send 
>events  
>for that Document, passing in now as the timestamp. [CSSANIMATIONS]
>]]
>
>The timestamp might be useful for .elapsedTime, but not for .timeStamp  
>(the latter is a timestamp from epoch, not from navigation start).
>
>css-animations needs to define what "run CSS animations and send events"  
>means.
>
>See http://dev.w3.org/csswg/cssom-view/#events for examples.
>
>What this is asking for is basically a major overhaul over how  
>css-animations is specified. At least the parts about events. With this  
>done it becomes well-defined what order all various events fire, and all  
>events and requestAnimationFrame callbacks have the same view of the 
>world.

‘Major overhaul’ doesn’t come any closer to clarifying what is needed :) 
Given the wide deployment of the feature I would at least like to 
understand whether/why this needs to be specified in Level 1. Though, in 
fairness, we could do a better job of explaining the various states of a 
CSS animations and when events are fired; I think that is worthwhile.

 
>

Received on Tuesday, 9 December 2014 17:46:38 UTC