Generating two-dimensional shapes from a structural model
Robert S. Louden, Linda G. Shapiro · ACM SIGSMALL Newsletter · 1982
In "A Structural Model of Shape" [1], L. G. Shapiro proposed a formal model of two-dimensional shape. This model consists of primitives, simple parts and intrusions, and their interrelationships. The interrelationships are two ternary relations on the primitives: the intrusion relation (Ri) which relates two adjoining simple parts to the intrusion they surround, and the protrusion relation (Rp) which relates two intrusions to the protrusion between them. In an attempt to determine what variety of shapes would come from any particular description, several approaches to working backwards from Ri and Rp relations to a class of shapes have been considered. The approach believed to be the most promising is that of producing topological 4-tuples of the form from the Ri and Rp relations and then applying the algorithm presented by Marvin S. White, Jr. in his AUTOCARTO presentation, "Coordinate Free Cartograph)" [2], to generate actual pictures of candidate shapes.