  We describe in this article a multiagent urban traffic simulation, as we
believe individual-based modeling is necessary to encompass the complex
influence the actions of an individual vehicle can have on the overall flow of
vehicles. We first describe how we build a graph description of the network
from purely geometric data, ESRI shapefiles. We then explain how we include
traffic related data to this graph. We go on after that with the model of the
vehicle agents: origin and destination, driving behavior, multiple lanes,
crossroads, and interactions with the other vehicles in day-to-day, ?ordinary?
traffic. We conclude with the presentation of the resulting simulation of this
model on the Rouen agglomeration.
