What the two programs miss is a truly generative process, in the sense of the design being obtained by some purposeful rules leading towards an unexpected formal result. Both programs are based on plain randomness as initial rule, and form is not generated but simply combined and slightly manipulated from a set of pre-designed objects. They are form driven instead of rule driven, although the forms are created using algorithms. There isn't a set of global rules above the object level. The result is never completely surprising to the designer, only more or less unexpected and weird. And for the user, if the designer tries to put to much control on the elements, can become repetitive after some experiments. There is a lack of the attractive complexity of cities.

My primary objective was to explore complexity and diversity in the design of virtual environments, in the context of the book "Invisible Cities" by Italo Calvino, using a computer program that produces real-time navigation. I understood that these two objectives cannot be achieved if the designer tries to take full control of the design result. He has to focus on the process that originates the architectural environment and on developing rules and systems that make the computer produce a reasonable and interesting result.

In this particular case, the use of selected quotations describing cities would make a good context for the creation of rules. Their interpretation, translated into a few simple behaviour algorithms, could produce better results than search for algorithms that produce a certain form.