Still wondering about directed graphs drawn from AppEngine

With reference to another case of pretty much the same question I have, Brightside asked: Library to render Directed Graphs (similar to graphviz) on Google App Engine

The accepted answer was "canvis", which looks very cool from a rendering perspective, but canvis just does the drawing. It still needs to call graphvis binaries for doing the layout, not so? Or what am I missing, in order to make sense of the author's "开发者_开发技巧Awesome! I just got it working on GAE. Thanks!" - possibly I will have to resort to manual layout via my own pure python code, when generating my graph specification in the dot language? (Else I'll resort to other options mentioned.)

Canvis doesn't call graphviz itself - it renders xdot directly in the browser. Of course you still have to have some way to generate xdot files, but canvis doesn't care where they come from.