Gravisto (Graph Visualization Toolkit) is a program for visualizing and editing graphs. Over the course of 15 years, many useful plugins have been developed to handle graphical information efficiently. Unfortunately, this open source project had recently become homeless and needed a new home.
A short history of the project
Professor Dr. Franz Brandenburg founded the project in 2001 at the Chair of Theoretical Computer Science at the University of Passau. The software was initially called Graffiti and renamed later. Under the direction of the computer scientists Michael Forster and Andreas Pick the graph editor and the plugin system were developed using Java and Swing.
After completion of the basic system in 2003, mainly plugins (algorithms, editor functionality, etc.) were added in the context of programming practicals, diploma and doctoral theses, but also by others, such as the Mavisto project. A major focus was on the development of layout algorithms. Thus, for example, an implementation of the Sugiyama-Framework (see Fig. 2) was created.
The Reingold-Tilford algorithm and some variants for circular drawing of trees are also available (see Fig. 3).
I contributed several plugins to Gravisto in the course of my diploma thesis back in 2006. The result was a toolbox of algorithms to layout hierarchical information compactly. I called it TreeJuggler, but if you look at the overall size of the project, my personal contribution was comparatively small at the time.
Loss and a New Beginning
Professor Brandenburg retired in 2018. Unfortunately, the project website and the SVN server of the Gravisto project went offline shortly afterwards. Despite some efforts, I could not obtain a current version of the source code including the source code history.
In order not to lose the work and knowledge of those who developed Gravisto, I have put a version from January 18th 2018 (unfortunately without history) on GitHub. Of course the source code is still available under the GPL license.
Still a Lot to Do
The documentation absolutely necessary to use Gravisto is already available in the GitHub repository, but there is still a lot missing:
- User documentation
- Developer documentation
- Source code history
- Blog posts about TreeJuggler
- Gravisto: Graph Visualization Toolkit (Poster), Graph Drawing Conference, GD 2004. [PDF]
- Bachmaier, Christian et al. “Gravisto: Graph Visualization Toolkit.” Graph Drawing (2004).
- Paul Holleis’s Gravisto page