Tips on implementing a new layout algorithm in Graphviz

Question

My partner and I are planning on implementing a new graph drawing layout algorithm of our design for use with Graphviz. We are new to Graphviz and though we've explored the source code, we're still unsure how to go about adding new layout functionality. Can you help with any pointers? I am looking for any of the following:

1. Overview of how other layouts are implemented. What files are most important?
2. What existing code we can draw upon? For instance, we would like to use an existing force-directed algorithm as part of our own algorithm, and we need to specify the shape of the edges.
3. Links to other projects that have implemented their own layout algorithm for use with Graphviz. Our searches so far haven't been fruitful, unfortunately.

Thank you very much!
-Kate

Answer 1

Thanks to Emden over on the Graphviz discussion board, we've found that there is a document called addingLayout.txt in the docs folder of the source code that is a guide for what we need to do. Emden elaborates further, with details about force-directed algorithms and how edges are described in Graphviz, on this thread: http://www.graphviz.org/content/how-implement-new-layout-style-graphviz --> fixed link at https://graphviz.gitlab.io/_pages/doc/addingLayout.txt