An urban grammar study: a geometric method for generating planimetric proportional and symmetrical systems

Abstract

This paper is part of ongoing research to explore (a) descriptive and generative potentials of shape grammars to unveil the order of urban morphological complexity underlying Portuguese treatises, and (b) the knowledge embedded in Portuguese urban cartographic representations produced from the sixteenth to the eighteenth centuries for purposes of architecture and military engineering. The shape grammar made it possible to infer the grammatical rules of composition based only on the written descriptions provided by the Portuguese treatises, as well as to decode the geometry of ideal urban plans and built cities. This paper suggests that these historical cities, both built and ideal were based on a structured knowledge-based process from where it is possible not only to retrieve a generative parametric urban grammar but also to construct a computational model, UrbanGENE, capable of iteratively generating Portuguese planimetric proportional and symmetrical urban systems. The paper suggests that the knowledge and computational tools achieved could be successfully deployed in the teaching and learning of architectural history.