W3C home > Mailing lists > Public > www-style@w3.org > December 2013

Re: Proposal: will-animate property

From: Robert O'Callahan <robert@ocallahan.org>
Date: Fri, 6 Dec 2013 08:18:30 +1300
Message-ID: <CAOp6jLYJ8F78rk+4mJbOg0XH+SX9VCCaqC7Mj29Q_K-O8mDbdw@mail.gmail.com>
To: Ali Juma <ajuma@chromium.org>
Cc: Nat Duca <nduca@chromium.org>, www-style <www-style@w3.org>, "L. David Baron" <dbaron@dbaron.org>, Benoit Girard <bgirard@mozilla.com>, Matt Woodrow <matt@mozilla.com>, Cameron McCormack <cmccormack@mozilla.com>, "Tab Atkins Jr." <jackalmage@gmail.com>, Ojan Vafai <ojan@chromium.org>
On Fri, Dec 6, 2013 at 6:09 AM, Ali Juma <ajuma@chromium.org> wrote:

> On Wed, Dec 4, 2013 at 8:57 PM, Robert O'Callahan <robert@ocallahan.org>wrote:
>
>> I understand what you've said, but it seems a little abstract to me.
>>
>> Can we just defer the introduction of "will-animate:positioning" until we
>> have a more concrete use-case for it, and a stronger argument that
>> alternatives such as automatic inference for that use-case are not tenable?
>> We can easily add it later if we need it.
>>
>
> I think the use case is situations like [1], where the actual animation is
> on the green box, but layerizing the blue boxes (which are effectively
> being moved) using the translateZ hack gives a roughly 10X speed up in
> paint time for Blink (specifically, paint time goes from roughly
> 1.5ms/frame to 0.15ms/frame on my Linux desktop).
>

This is too low-level to be a use-case. A use-case is the effect an author
is trying to achieve. There may be valid alternative solutions such as
changing the markup.

So I think the spec needs to address the "right" thing for authors to do
> here. I don't think we want the spec to require that UAs perform inference
> on will-animate values (unless there's a strong argument that this can be
> done efficiently in general -- I'll leave this part of the discussion to
> others, since I'm not familiar enough with the complexity of layout to
> usefully contribute),
>

When introducing the a new feature, there is a burden of proof (for a low
standard of "proof" :-) ) that it can't be done automatically, not the
other way around.

Rob
-- 
Jtehsauts  tshaei dS,o n" Wohfy  Mdaon  yhoaus  eanuttehrotraiitny  eovni
le atrhtohu gthot sf oirng iyvoeu rs ihnesa.r"t sS?o  Whhei csha iids  teoa
stiheer :p atroa lsyazye,d  'mYaonu,r  "sGients  uapr,e  tfaokreg iyvoeunr,
'm aotr  atnod  sgaoy ,h o'mGee.t"  uTph eann dt hwea lmka'n?  gBoutt  uIp
waanndt  wyeonut  thoo mken.o w
Received on Thursday, 5 December 2013 19:18:57 UTC

This archive was generated by hypermail 2.3.1 : Monday, 2 May 2016 14:39:17 UTC