Examining the Compactness of Automatically Generated Layouts for Practical Diagrams

Graph drawing algorithms have important practical applications, e. g. layer-based algorithms for data flow diagram layout in embedded software design and planarization-based algorithms to layout UML diagrams in software engineering. Most current drawing methods focus on the optimization of aesthetic criteria such as the number of edge crossings and bends. The aspects of compactness and aspect ratio are often treated with lower priority, but in practice these are important as well. We present computational experiments showing that compactness can become a problem, especially for large and nested diagrams. Furthermore, we discuss possible new research directions.