We present a simple, linear-time algorithm to determine horizontal coordinates in layered layouts subject to a given ordering within each layer. The algorithm is easy to implement and compares well with existing approaches in terms of assignment quality.
Fast and Simple Horizontal Coordinate Assignment
JSON-java: A reference implementation of a JSON package in Java
Two kinds of new methods are developed to obtain effective representations of hierarchies automatically: theoretical and heuristic methods. The methods determine the positions of vertices in two steps. First the order of the vertices in each level is determined to reduce the number of crossings of edges. Then horizontal positions of the vertices are determined to improve further the readability of drawings. The theoretical methods are useful in recognizing the nature of the problem, and the heuristic methods make it possible to enlarge the size of hierarchies with which we can deal. Performance tests of the heuristic methods and several applications are presented.
Methods for Visual Understanding of Hierarchical System Structures
IEEE Transactions on Systems, Man, and Cybernetics
ELK: Eclipse Layout Kernel - Automatic layout for Java applications
In graphical modelling, the arrangement of diagram elements can be a tiresome and mechanic work. To free users from this, layout algorithms arrange the diagram elements automatically. Different modelling domains require different layouts. A layout approach suitable for data flow diagrams is the layered layout approach. This approach is structured in several phases, of which one is called node placement. Present implementations are known to produce many edge bends. One task of this thesis is to employ a node placement algorithm which yields significantly less edge bends. Another well known problem in layout algorithms is label placement. Present approaches rely on a post-processing by placing labels after the diagram has been laid out. The approaches presented in this thesis integrate label placement into the layout, resulting in more freedom and clean placements of labels. Evaluation shows that both tasks can be fulfilled, but have to accept a trade-off which is a generally larger drawing of the respective diagrams.
Node and Label Placement in a Layered Layout Algorithm
Carstens - Node and Label Placement in a Layered Layout Algor.pdf