September 25, 2008

Roughly sketch your diagrams

In recent posts I have already demonstrated the power of diagram completion.

In the paper I have presented at this year's LED workshop, I have shown how diagram completion can be used in order to facilitate a completely novel(?) approach to diagram editing. It is enough to just roughly sketch your diagram. You do not need to hit the mark quite precisely anymore as required in traditional diagram editors. Rather the completion engine computes all ways, how the diagram can be put together. Thereafter, the completion causing minimal change to the layout of existing diagram components is selected automatically! I am quite sure that this feature can boost the accessibility of diagram editors.

Example:

This figure shows how tedious the manual correction of a roughly sketched diagram can be. At least three complex mouse dragging operations are necessary here. The completion engine would yield two results for this example, the diagrams A and B given in the upper row. However, it is quite clear which diagram the editor user would prefer: the one with minimal changes to his components, namely A. A shortcut that automatically applies completion A could greatly improve editing performance.

However: This approach is only possible as long as there are not too many possible compositions of the fragements. For instance, n disconnected NSD statements can be put together in n! ways. As a consequence, the user would have to invoke the completion engine every few steps. Even so, this kind of assistance is still useful.

September 16, 2008

Visual Week up and running

The Visual Week in Herrsching, Germany is already up and running. Yesterday the Workshops Layout of (Software) Engineering Diagrams and Sketch tools for diagramming took place. I attended LED where I gave a talk with the title "Exploiting the Layout Engine to Assess Diagram Completions" (paper and slides). But I also really enjoyed the other talks that covered a wide range of topics from industry projects to sophisticated graph layout approaches. A highlight was the 3D UML Heuristic Challenge. We have been divided in several groups and had to solve given tasks. My group had to think about the differences in 2D and 3D usability heuristics and, subsequently, evaluate a given tool using the heuristics we just developed.

Today the ACM SoftVis conference has started and a graduate consortium took place (many exciting new ideas!).