FEATURE BASED QUALITATIVE REPRESENTATION OF ARCHITECTURAL PLANS Information contained in 2-dimensional design drawings. JOHN S. GERO AND JULIE R. JUPP Key Centre of Design Computing and Cognition University of Sydney NSW 2006 Australia Email address: {john, jupp_j}@arch.usyd.edu.au Abstract. This paper develops an approach to the qualitative representation of architectural plan drawings. We describe a schema for representing the internal shapes features and their associated spatial relations using syntactic pattern and contour specifications. This schema uses a qualitative symbolic representation to detect features. An example application of this representation is presented. 1. Introduction This paper describes a qualitative approach to the modelling of 2- dimensional drawings applicable to representing architectural plans. The aim of our approach is to produce a canonical representation that captures information relating to the qualitative character of the drawing and to computationally analyse and compare a corpus of architectural plans. We draw on the work of Gero and Park’s (1997) feature-based qualitative modelling of shapes known as Q-codes to develop a representation of shape and spatial relations. In a previous paper (Gero and Jupp, 2002) we identified the need to represent not only the 1- dimensional shape features in the Q-code schema but to include 2D spatial features, that is, the design drawing’s internal topology. We expand the existing Q-code schema to describe information derived from both shape and spatial characteristics whilst maintaining the feature-based approach and the equivalent analogy with language. The extension represents classes of shape features that include symbolic descriptions of their organization.