Re: [css-compositing] blending and inline SVG

On Mon, May 20, 2013 at 3:42 PM, Dirk Schulze <dschulze@adobe.com> wrote:

>
> On May 20, 2013, at 3:39 PM, Rik Cabanier <cabanier@gmail.com> wrote:
>
> >
> >
> > On Mon, May 20, 2013 at 1:55 PM, Dirk Schulze <dschulze@adobe.com>
> wrote:
> >
> > On May 20, 2013, at 11:16 AM, Rik Cabanier <cabanier@gmail.com> wrote:
> >
> > > All,
> > >
> > > I was editing the chapter on isolation [1] and wondered if inline svg
> should happen in an isolated group. (So the <svg> tag would establish a new
> group/stacking context)
> > > It seems that it would be very hard to implement if this was not the
> case.
> > >
> > > Is everyone that inline SVG is always isolated?
> > >
> > > We also need to discuss what other constructs in SVG create isolation.
> The current filter spec assumes that nothing does, but that doesn't
> correspond with reality.
> >
> > The first question is how inline SVG cooperates with HTML in general. We
> did not specify that anywhere to my knowledge. In Blink and WebKit inline
> SVG elements are handled as replacement elements, same as <img>, <video> or
> <canvas>. It would make sense to not treat inline SVG elements different
> from the other elements for these two engines. However, I would like to
> understand where you see the technical difference to other "graphical" HTML
> elements like <div> or <p>.
> >
> > I'm unsure what you are asking.
> > Browser are indeed treating svg as a canvas (and not as a change from
> the css box model to the svg drawing model) so it makes sense to have the
> content isolated.
>
> I was more revering to the sentence "It seems that it would be very hard
> to implement if this was not the case.". The question is why it would be
> harder for SVG. Treating SVG as replacement element is not necessarily a
> problem for not having an isolation group IMO.


Not neccesarily, but as you know, the graphics engines that the browser
rely on, are not set up to deal with non-isolated groups.
Do browsers create a new context when they see an inline SVG?



> The question is although: Should <video> always create an isolation group?
>

Does it matter? There is no visible content inside the video tag.