The purpose of this research work was to modelise urban town codes on computer. In so far as a town code defines the rules for urban form creation, it symbolises a generic representation of the resulting town. The code is comprised of a vocabulary of urban attributes, concerning building height, placement on the building lot - in particular the relation with the street and the public realm - density, etc. The architectural project on a particular site constitutes an instance derived from these rules.

The computer, itself a machine that manipulates data through a programme of code, is a useful tool for representing urban tissue. Thus one may generate a virtual town, not by laying out an agglomeration of architectual artefacts, but as a materialisation of rules and the range of the variations which they permit within the framework of their defining typology. What may take ten or twenty years on the ground and cannot be deleted if it results in a damaging environment, may be designed and tested as hypotheses on the computer.

The Town Simulator was developed at the CIMA (Centre d'Informatique et Méthodologie en Architecture) in Paris, where I was able to conduct research in urban representation in 1989.

The Town Simulator was used on a project in the Paris suburb of Herblay (architects Levincent and Samson). Such images were very useful in explaining the project to the municipality.

Generation of urban form from town codes (right hand image).

Generic window forms for urban representation, generated by the Town Simulator.

Generic facade forms for urban representation, generated by the Town Simulator.

The CIMA was a laboratory working on three dimensional imagery and artificial intelligence in architecture and urbanism. My position there was part of professional training I undertook in "communication and computer graphics for architects" organised by the INA (Institut National de l'Audiovisuel).

My brief on arrival at the CIMA was to modelise how "rooms make an apartment, apartments make a floor, floors make a building, buildings make a quarter, quarters make a town"… an architecturally biased view of urban space that symbolises the opposition between an individualistic and collective perception of the town.

Considering this view simplistic and incorrect, I set out to demonstrate how a town's morphology is a manifestation of the concepts that underlie its urban code. Thus I developed a prototype for a Town Simulator, showing how a particular urban code would always create generically similar urban tissue.

The Town Simulator used the three dimensional modelling environment, "Iko", developed at the CIMA by Michel Bret (mathematician and artist, pioneer of computer graphics in France).

This work was presented at the "European Conference on the Management and Representation of Urban Transformations" that took place at Queen's College, Cambridge, in September 1989, where I presented a paper, "Towards the simulation of urban morphology". This paper was published in "Environment and Planning B: Planning and Design", 1991, volume 18.

An article about the Town Simulator was published in "Cree - Architecture Intérieure", December 1989.