Re: [css-compositing] new Editor's draft posted -> update

On Fri, May 24, 2013 at 9:45 AM, Robert O'Callahan <robert@ocallahan.org>wrote:

> On Fri, May 24, 2013 at 11:09 AM, Rik Cabanier <cabanier@gmail.com> wrote:
>
>> I think there is now a clear path on how to calculate the backdrop for
>> HTML but how to calculate it for SVG is still in question.
>
>
> I don't really understand this. The issues in SVG are a strict subset of
> the issues in HTML. We should make SVG follow HTML and dispense with
> "enable-background".
>
> Filters, blending and opacity should probably cause isolation...
>
>
> The spec says stacking contexts cause isolation, so these already do.
>

Unfortunately, the SVG spec has a different definition on how the backdrop
is calculated, see
https://dvcs.w3.org/hg/FXTF/raw-file/tip/filters/index.html#enable-background
As I previously mentioned, that definition is incorrect so I believe we
should 'enable-background' and harmonize SVG with CSS. At a later point in
time, we can add support for non-isolated groups which is what the SVG spec
attempted to do.

IE did implement this though so we need to tell them to update their
browser. Hopefully few people used this. If they did, maybe we can define
it in a way that is still backward compatible.