Re: CSS Animations Targeting SVG attributes

On Tue, Mar 15, 2011 at 11:05 AM, Tab Atkins Jr. <jackalmage@gmail.com>wrote:

> On Mon, Mar 14, 2011 at 2:05 PM, Robert O'Callahan <robert@ocallahan.org>
> wrote:
>
> OK, that implies a hard requirement that arbitrary CSS rules be able to
> > override any SVG attribute value. Whatever syntax you choose, that means
> > effectively minting a lot of new properties. Someone should make a list
> of
> > all the new properties that will be needed.
>
> Correct, that's a hard requirement.  Cameron pointed out such a list.
>

No, that's a partial list of attributes Patrick suggested should be
supported "initially".

To compare these proposals, we need to consider the entire set of animatable
SVG attlributes, discard any which we agree will *never* need to be
animatable via CSS, and consider the cost of promoting all of the rest to
CSS properties --- because that's the state proposal #2 is aiming for.
There's no benefit in promoting some subset now and some subset later; in
fact that will be more confusing for authors.

I think the best approach might be to promote *all* animatable SVG
attributes to CSS properties, but I'm not sure yet. One problem is that in
Gecko, and I think Webkit and other engines, mapping presentational
attributes into style typically requires additional storage for internal
"presentational CSS rules" and computed CSS style, so the footprint of
element-heavy SVG pages could increase noticeably even if CSS animation is
not used.

Rob
-- 
"Now the Bereans were of more noble character than the Thessalonians, for
they received the message with great eagerness and examined the Scriptures
every day to see if what Paul said was true." [Acts 17:11]