libgnomecanvas が Postscript の描画モデルを使ってる、と README には書かれてるが…

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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.
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