Visualization is a first class citizen in Glamorous Toolkit.
Currently, the projects contains:
Mondrian, a fluent API for scripting graph-based visualizations.
Treemap, for building circular and rectangular treemaps.
Plotter, a collection of builders of charts like bar charts or timelines.
Connector, an engine that allows you to create a visual way to navigate graphs.
For example, below we can see an instantiation of the engine for navigating examples. Just click on the dots.