A generic layout algorithm for meta-model based editors

Abstract

The diagram editor generator framework DiaMeta utilizes meta-model based language specifications and supports free-hand as well as structured editing. This paper describes a generic layout algorithm that meets the demands of this kind of editors. The underlying concept of the algorithm is attribute evaluation. An attribute evaluator is best suited for an unambiguous layout, i.e. the diagram may not be represented in different ways. Especially in free-hand mode we want to give more freedom to the user when he edits a diagram, and thus a plain attribute evaluator is not sufficient. Therefore we combine this approach with a constraint satisfaction approach in the sense that constraints are used to activate particular attribute evaluation rules. This gives the layouter the flexibility it needs to deal with the situation in DiaMeta. © 2008 Springer Berlin Heidelberg.