Visualizing Regions with a new Split-Screen View for the Online Tool travis

The online tool travis can synthesize a k-bounded Petri net model from a reachability graph and unfold a k-bounded Petri net to its reachability graph. Synthesis is built on the theory of regions, but where travis and other existing tools only show the synthesized model, we want to present the synthesized model as well as the calculated regions after a user has performed the synthesis procedure. In this paper, we present a new split-screen module of travis which is able to visualize regions, calculated during the synthesis procedure, as well as markings of places related to single states of the reachability graph, calculated during the unfolding procedure. Both sets, i.e. regions and markings, help to really understand the relations between the behavioral and the synthesized models at hand, as well as the underlying fundamental concepts of state-based synthesis and reachability analysis. With these new features, travis is tailored to be used in a teaching environment to help students understand the concepts and notions of state-based synthesis.