A method for interactive graph manipulation

As structured graphs are widely used in various application areas for conceptual modeling, the need for interactive layout adjusting methods is clearly recognized in the domain of graph drawing applications. We present a graph manipulation method where the process of adjusting and manipulating graphs is broken down into a group of direct and interactive tools. The tools are visualized as large tool-specific mouse cursors that are easily adjustable. Colors and highlighting are used to identify different tools and their operating ranges. According to the usability studies, the tools proved to be reasonably easy to use with only a short introductory time. The users could also select appropriate tools for each manipulation task without problems and were satisfied with the functionality as well as the visualization of the tools. The usefulness of the tools in manipulating graph drawings was also recognized.