GraphVizio – A Graphviz addin for Visio
In the process of analysing a client’s existing database, I used Visio’s reverse-engineering tool. It works well, but the resulting diagram was an incomprehensible bowl of spaghetti. Visio does have a “Layout shapes” command, which appears to work by moving shapes with repulsive forces and the result is, not surprisingly, repulsive.
What I wanted was a tool which would unravel the spaghetti, so that I could get a grasp of the relationships, edit and revise them and layout again in an iterative process.
Searching for a solution, I found three layout programs, none of which have a Visio interface:
- Microsoft Automatic Graph Layout (MSAGL), formerly known as GLEE The first version, GLEE, is free whereas MSAGL costs between 99 USD and 279 USD depending on where you buy it.
- Tom Sawyer Layout is also a graph layout library, the price isn’t disclosed on their website.
- Graphviz from AT&T research labs, reputed to have the most sophisticated layout algorithms, is free.
Given that the best quality was to be found in the free library, I made the obvious choice.
It took me over a year and some 11’000 lines of VB to get Visio and Graphviz to co-exist; marrying a Unix-style command-line program with a WYSIWYG interface, both with quirks to numerous to mention, was far more challenging than I initially thought.
The result, unimaginatively called GraphVizio, is available here, I hope you’ll find it useful.
Calabi Yau manifolds
Stumbled upon Calabi Yau manifolds quite by chance, they attempt to represent 10-dimensional space in string theory. I don’t understand a word of the article but they struck me as rather pretty geometry:
Here are some high-resolution images that I made with the excellent POVRay renderer.
Enjoy.