Size- and Port-Aware Horizontal Node Coordinate Assignment

The approach by Sugiyama et al. is widely used to automatically draw directed graphs. One of its steps is to assign horizontal coordinates to nodes. Brandes and Koepf presented a method that proved to work well in practice. We extend this method to make it possible to draw diagrams with nodes that have considerably different sizes and with edges that have fixed attachment points on a node's perimeter ports. Our extensions integrate seamlessly with the original method and preserve the linear execution time.