Re: Rendering arbitrary SVG content in SVG font glyphs

On Mon, Sep 14, 2009 at 7:49 PM, Erik Dahlstrom <ed@opera.com> wrote:

> I see what you mean now. In my interpretation this never meant you need to
> do any cloning, just that you need to construct a shadow-structure that
> contain references to the original subtree/elements. However, the wording in
> the spec does require something like a deep clone at the moment for cases
> like the one you mention. I would be in favour of changing the spec so that
> it doesn't imply or require actual deep cloning.
>

One more thing is that style resolution is often expensive, and if style can
inherit from the site of a <use> or <text> into the "shadow content" then
you basically have to do style resolution for each "shadow node" no matter
how you to choose to represent that shadow node internally, and whether you
keep it around between paints or not. So basically I think any feature that
allows style to inherit from the usage site into the "shadow structure" is
guaranteed to be expensive in time, space, complexity or all three, whether
cloning semantics are required or not.

Also, in Gecko our style resolution and rendering code assumes there is some
kind of explicit shadow DOM. Trying to render the "shadow structure" with
style resolution inheriting different values at each usage site but without
constructing actual shadow DOM elements for each site would be very
difficult to do. I'd be interested in hearing other implementors' opinions
on this.

Rob
-- 
"He was pierced for our transgressions, he was crushed for our iniquities;
the punishment that brought us peace was upon him, and by his wounds we are
healed. We all, like sheep, have gone astray, each of us has turned to his
own way; and the LORD has laid on him the iniquity of us all." [Isaiah
53:5-6]