Implementing the Features 3D Multipatch for the Management of Territorial Infrastructures

The 3D geographic information has now become fundamental in the analysis and prevention of many environmental problems. For some application fields the simple 3D data visualization is required, but the 3D complex objects can be considered as a great aid in territorial analysis connected to specific areas, for instance the management of territorial infrastructures. In order to meet such requirements, the latest generation of CAD software has improved the editing and the photorealistic visualization of objects for mechanics and industrial fields, whereas GIS software, with the use of georeferenced points, lines and polygons, had emphatically developed tools for the spatial analysis of objects. So far, with visualization tools based on simple extrusions, both the technologies do not permit structuring of 3D topological models and visualization of complex entities. In literature there are substantially object-oriented and topology-oriented models. The first addresses the visualization, topology and spatial relations derived from the object’s structure, while in the second, connected to analysis, relations are explicitly defined between one object and its neighbours. With this study the 3D cartographic data processing of road networks for the realization of a prototype Infrastructure Management System was evaluated, in order to allow spatial processing in 3D GIS environments, also divulged by web. Particular attention was paid to the potentiality of the CAD-GIS tandem using the feature type Multipatch, in order to investigate the real possibility of using this methodology in many territorial application fields. The Multipatch permits one to encapsulate complex objects in a compact way and also to add textures on surfaces, providing a real objects visualization. Such a technique is still not used because commercial GIS software does not have specific tools to create feature 3D Multipatch. The created objects were next visualized to verify the effective possibility of thematic queries.