Gtk/CSS update

[Robert Staudinger <robert staudinger gmail com>]

Hello,

seems everyone went back to their cubicles and put the heads down
after the Dublin theming event, so here's a brief update for the CSS
part.

Libccss [1]
-----------

The CSS library is now used in Intel's Moblin stack, providing CSS
functionality to the clutter-powered netbook toolkit. This guarantees
maintenance, exposure and regular scrutiny, at least of the parts
relevant to Nbtk.

Mid-term plans include writing a simple CSS parser instead of using
libcroco, this should make it easier to support CSS3 constructs and
play with CSS animations [2].

Gtk-CSS-Engine [3]
------------------

Going a bit slow lately as things focus around the library, but it's
being kept up to date with libccss. Will roll a release once I have a
basic theme that somewhat works desktop-wide.

CSS Theming
-----------

In addition to "regular" gtk/css themes, which would typically
comprise of gtkrc, CSS file and PNGs we've continued working on a
single-canvas theming approach. The plan is to have the theme pretty
much entirely in a single SVG file and extract/render parts using
librsvg. We're following the single-canvas icon themes in that theme
parts are located by "plates", invisible elements that determine
boundaries. An in-progress theme template can be found at [4].

[1] http://people.freedesktop.org/~robsta/libccss/
[2] http://webkit.org/specs/CSSVisualEffects/CSSAnimation.html
[3] http://www.gnome.org/~robsta/gtk-css-engine/
[4] http://bazaar.launchpad.net/%7Ecascaders/ubuntu-artwork/css_themes/revision/29/pioneer.svg

Best,
Rob