I just wonder what is necessary to use Roassal not only as a visualization engine of existing data but to give it more interactivity to create new data/shapes/connections. An example: one can build a UML class shape and visualize the existing class hierarchy of Pharo with the current engine. But is it possible to also hook into the engine so one can have a palette and by visually adding new nodes (here UML classes) and wire them visually to create new classes in the system and use it as a modeling tool too? Simply said: whats required to additionally transform it into a universal diagram tool with palette for custom shapes and connections, outline, custom menues on shapes/nodes/connections to open dialogs, properties page ... Something similar to GEF from Eclipse http://www.eclipse.org/gef/ http://www.eclipse.org/articles/Article-GEF-diagram-editor/shape.html I'm sure this would open up lots of opportunities to build graphical applications with Pharo. Thx T.