A Co-operative Graphical Editor Based on Dynamically Constrained Objects

A co-operative graphical editor is introduced as an efficient drawing tool for structural and functional design. The components of the artifact being designed are represented as objects. A design can be modified by direct manipulation of the 2D graphical presentation of its components. The criteria for consistency of a drawing are declared in the form of abstract rules, prescribing what relations should hold for which object instances in the drawing. In the course of the drawing process, constraints are generated from the general prescriptions and resolved dynamically, ensuring the given state of the drawing. The editing operations are defined with respect to the constraints. The graphical editor assures the consistency of a drawing on the basis of a specific constraint satisfaction mechanism. The editor is discussed with reference to the specific application domain of interactive design of planar welding fixtures. However, the basic concepts and the constraint satisfaction mechanism are general enough to be used as a framework for other domain-specific editors. The modular and open architecture of the editor assures adaptivity to other application domains.