3D CITY MODEL GEOVISUALIZED ON GOOGLE-EARTH
E.S. Malinverni, G. Cassatella, G.A. Gentile
Università Politecnica Marche, Engineering Faculty, DARDUS, Ancona, Italy
In recent years, significant progresses have been made in the development of 3D city models. After millennia of traditional maps new uses are opening a new concept of map. Today the existing technology is able to provide detailed simulations of urban environments. They can be used for visualizing the reality setting up different 3D scenarios in local or remote mode (Internet/Intranet). The new age of Google Earth has opened the way to 3D interactive environmental. Google Maps application allows to the users to put on the Web personal models and to other ones to discover, visualize and use these models. These popular applications are growing much faster and providing new perspectives of using spatial data for better and earlier decision making. 3D models have a variety of applications in geography, urban, tourism and culture aspects: site location analysis, facilities planning, marketing, disaster management, environmental simulations and so on. Nevertheless sometime all that require more sophisticated models beyond visualization. Generally, these models of cities or scenes have varying degrees of detail and artistic rendering but that depends on the application. This paper presents a process for building a 3D city model mainly for realistic visualization and Web manipulation on Google Earth. The aim of the approach was to make use of various data sets coming from different sources as digital cartography at high scale completed by terrestrial surveying, orthoimages, digital elevation and surface models, to realize the 3D city model of the water-front of Ancona (Italy). The investigation was focused into two important tasks. The first task was to construct a model geometrically correct and second one was to perform the model to the public access on the Web. The major efforts of the research was devoted to the construction from the row data and their storage. In the common case buildings are described using faces, but another method assumes some simplification of the row data in order to obtain regular “boxes”. This method reduces to the certain degree of the amount of data and this has allowed the use of active representation and good performance on Internet.