UML Class Diagrams - State of the Art in Layout Techniques

Even if the standard for specifying software, the Unified Modeling Language, is known in different versions to everybody, CASE tool vendors did not implement all basic features. Even with class diagrams, many features of the standard are ignored. Applying the layout algorithms of these CASE tools to the user defined diagrams, usually horrible results are produced, because state-of-the-art techniques in drawing these diagrams are not respected by the vendors, too.
In this paper we give an overview on the current UML tool implementations, the research in the field of drawing class diagrams automatically and the efforts in convincing the community of an agreement on basic aesthetical principles for UML class diagrams in order to simplify reading and understanding of standardized visualization of static aspects of software.