[xdot] Parse into an intermediate dict/array structure before rendering.

[GoogleCodeExporter]

I'm using http://raphaeljs.com/ to render digraphs to svg/vml and needed an
xdot parser for parsing xdot into a JSON structure.
The first one I tried was dot_parser.py which uses pyparsing and was very slow.
Then I tried yours and found it to be impressive fast even for large graphs.
But your cairo drawing operations are hardwired to the parser so I had to
hack in some changes to construct a dict/array structure which I feed
through minjson.
I basically replaced XDotAttrParser with some regular expressions to get
polygon points for the edges and arrow heads from attrs.
To get rid of the gtk dependance I resolve the color names with a dict.
This is all very hackish at the moment but is ok for my project.
You can see a very early proof of concept at:
http://atomar.de/graphael/test01.php

Maybe you can separate the parsing from the drawing in a future version so
xdot.py can also be used as a xdot parser library? :)

best regards

Thomas

Original issue reported on code.google.com by Vindo...@gmail.com on 29 Mar 2009 at 7:43