GNOME Bugzilla – Bug 332372
GTK needs to provide API for themes to draw directly on cairo context
Last modified: 2010-12-22 20:56:35 UTC
By allowing themes to draw on a passed in cairo context, mozilla can render native widgets must faster. See http://lists.freedesktop.org/archives/cairo/2006-February/006402.html for discussion.
I don't think this is possible without breaking the current theme API, so this would probably have to wait until a new major release of GTK+.
Or, introduce a new theme API that doesn't suck and deprecate the old one. Even better, have new widgets not support the old theme API and draw nothing at all.
I'm going to look into providing the current theming features for a cairo context during GTK+ Hackweek.
GtkStyleContext addresses this.