GraphvizFiddle (viz.js 2.1.2 release, with circo/dot/fdp/neato/osage/twopi engines)

GraphvizFiddle draws DOT language [directed] graphs, see DOT User's Guide (on http://graphviz.org/).
It is an online code editor and playground for Graphviz dot layout tool, based on viz-js from Mike Daines.

After drawing the layout, engine and format will snap back to defaults (dot/svg).
Adding eg. "layout=neato" setting to (di)graph (for "Share" links) overrides engine selection.
Choose the engine and format you want and press "Draw".    (NEATO User's Guide, engine manpage)
Engine specific settings (eg. "overlap") don't hurt for engines not supporting them (eg. "dot").

Click on "Share" and the address bar will get a URL completely describing your layout.
Bookmark that, or copy and chat or email it to someone, use in web pages, ….

DOT input & control   new/ʍǝu blog posting 2   
initial ortho scalable number rho-221 LA1 (from Graphviz Gallery: cluster crazy datastruct fsm hello switch)

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