The GNOME canvas is an engine for structured graphics that offers
a rich imaging model, high performance rendering, and a powerful,
high-level API. It offers a choice of two rendering back-ends:  one
based on Xlib for extremely fast display, and another based on Libart,
a sophisticated, antialiased, alpha-compositing engine. Applications
have a choice between the Xlib imaging model or a superset of
the PostScript imaging model, depending on the level of graphic
sophistication required.
