  Urban morphogenesis is the process of formation of its elements and the
specialization of its suburbs. Street networks are the structural part of the
system. Understand their formation reveals crucial information about urban
transformation and dynamics behind its functioning. In this work we focus on
the morphogenesis of street networks and we study it through a spatial network
generator model. This latter is composed by three layers (a reaction-diffusion
layer, a dynamic vector field and a spatial network) surrounded by an
environment. The emerging network feeds back to its morphogenetic elements,
driving the model to an unexpected behaviour. We applied the model in a real
urban context (F\'ecamp town, Normandy, France) and we measure properties of
obtained networks.
