Edge Label Placement in Layered Graph Drawing

Many visual languages based on node-link diagrams use edge labels. We describe different strategies of placing edge labels in the context of the layered approach to graph drawing and investigate ways of encoding edge direction in labels. We evaluate the label placement strategies based on both common aesthetic criteria and a controlled experiment. We find that placing labels on their edge can lead to more compact diagrams. Also, placing labels with additional arrows indicating edge direction can help users navigate in large diagrams and is generally preferred by participants of our experiment, outperforming other ways of indicating edge direction

3DScape: three dimensional visualization plug-in for Cytoscape

3DScape is the first plug-in which enables three-
dimensional network visualization in Cytoscape. The extra dimension is useful in accommodating, visualizing, and distinguishing larger networks with multiple crossing connections.
Special features in 3DScape include 3D layout algorithms, mapping onto 3D models and animation effects on a series of expression data. 3DScape is available at http://www.rendware.co

Drawing Activity Diagrams

Activity diagrams experience an increasing importance in the design and description of software systems. Unfortunately, previous approaches for automatic layout support fail or are just insufficient to capture the complexity of the related requirements. We propose a new approach tailored to the needs of activity diagrams which combines the advantages of two fundamental layout concepts called "Sugiyama's approach" and "topology-shape-metrics approach", originally developed for layered layouts of directed graphs and for orthogonal layout of undirected graphs respectively

Crossing Minimization for 1-page and 2-page Drawings of Graphs with Bounded Treewidth

We investigate crossing minimization for 1-page and 2-page book drawings. We show that computing the 1-page crossing number is fixed-parameter tractable with respect to the number of crossings, that testing 2-page planarity is fixed-parameter tractable with respect to treewidth, and that computing the 2-page crossing number is fixed-parameter tractable with respect to the sum of the number of crossings and the treewidth of the input graph. We prove these results via Courcelle's theorem on the fixed-parameter tractability of properties expressible in monadic second order logic for graphs of bounded treewidth.Comment: Graph Drawing 201

Automatic Layout of Data Flow Diagrams in KIELER and Ptolemy II

Data flow diagrams are successfully applied in the area of model-based design of complex embedded systems. However, their creation and maintenance can be very time-consuming, because many tools offer little support for the editing and visualization of graphical models. The KIELER project explores new concepts for the pragmatics of graphical modeling and develops algorithms for automatic layout of specific classes of diagrams. These concepts and algorithms are implemented as extensions of the Eclipse framework, which offers generic approaches to create IDEs for graphical modeling. We have developed a specialized layout algorithm for data flow diagrams. In addition to the embedding in KIELER, we applied this algorithm to Ptolemy, a framework for research on models of computation for use in embedded systems. The results show that our algorithm is well suited for the actor oriented diagrams of Ptolemy, and it can serve as a basis to facilitate the editing of Ptolemy diagrams

Layered Drawing of Undirected Graphs with Generalized Port Constraints

The aim of this research is a practical method to draw cable plans of complex machines. Such plans consist of electronic components and cables connecting specific ports of the components. Since the machines are configured for each client individually, cable plans need to be drawn automatically. The drawings must be well readable so that technicians can use them to debug the machines. In order to model plug sockets, we introduce port groups; within a group, ports can change their position (which we use to improve the aesthetics of the layout), but together the ports of a group must form a contiguous block. We approach the problem of drawing such cable plans by extending the well-known Sugiyama framework such that it incorporates ports and port groups. Since the framework assumes directed graphs, we propose several ways to orient the edges of the given undirected graph. We compare these methods experimentally, both on real-world data and synthetic data that carefully simulates real-world data. We measure the aesthetics of the resulting drawings by counting bends and crossings. Using these metrics, we compare our approach to Kieler [JVLC 2014], a library for drawing graphs in the presence of port constraints.Comment: Appears in the Proceedings of the 28th International Symposium on Graph Drawing and Network Visualization (GD 2020