Urban Engine - live demo of 3D real-time in action from Urban Circus on Vimeo.
Embedded above is a real-time look at the Urban Engine presented by Dr Ben Guy, Director of Urban Circus.
The engine seems impressive, especially in terms of transport visualisation, below is an example of using the engine to visualise a proposed transit station in Broadbeach on the Gold Coast of Australia:
Bus Rapid Transport - Broadbeach from Urban Circus on Vimeo.
The ability to fly real-time through a scene is without question one of the most important aspects of city models for urban planning / architectural visualisation when aiming to communicate 'non fixed' design decisions. Highly rendered fly through movies can often alienate the public at large as it seems as if planning decisions have already been taken, leaving the renderings to come across as sometimes little more than marketing movies.
Take a look at http://www.circus3d.com/ for more info.