Corso base di GIS per archeologia - Verona 2013 (part 3) (original) (raw)
OpenSource philosophy has reached to unexpected goals. The diffusion of OpenSource tools is increased quite a lot, but also the quality of the tools is improving. Their usability is slowing going even towards communities not exactly skilled in advanced programming. Open movement is penetrated in many sectors, often subverting, thank to its social impact, the traditional rules of companies and research institutions, pulling down sometimes hierarchies and pushing on innovative ideas because of their validity and values. Even fields that until now were a bit apart, such as Cultural Heritage field but also land-management, are starting their first experiences. There are many perspectives of development, indeed, in sectors that need to use carefully and cautiously the few economical resources they can dispose. Build an OpenSource project has meant for us to experience many advantages (together with some difficulties): low cost of the solutions, sustainability of the projects, push toward resources sharing, simplicity in the re-use of data already processed and in integration of known and well established methodologies, valorisation of ‘human’ investments more then on ‘technology’. This lead the two interdisciplinary teams, that had a long skill in the development of immersive environment and of virtual reality systems and in the reconstruction of ancient landscapes through digital technologies (CINECA Visit Lab and CNR ITABC VHLab), to undertake a new parallel research activity dedicated to the construction of desktop and web-based VR applications based on OpenSource tools. The system realised is based on two open projects: OpenSceneGraph library (www.openscenegraph.org) and Virtual Terrain Project (www.virtualterrain.org). They were used in combination, modifying partially the code and adding plugins, in order to create a system useful to reconstruct complex landscapes, starting from GIS data (DEM, GeoImages and vectorial data in standard format such as .shp). GIS data are used to build a three-dimensional terrain through a powerful tool, OSGdem, that generates paged and hierarchy terrain databases. OSG was integrated with VTP, whose original code was modified so to import even different terrain database formats (flt, txp, ive). Inside VT Enviro it’s possible to modify dynamically, three-dimensionally and in real time the landscape, using external libraries of 3d models, vegetation, animals, etc. (based on xml) or inserting directly on the scene, in a defined geographical absolute coordinate, the models. We then implemented OSG potentialities of .ive files publication over the Web, allowing VT Enviro to export the modified landscape. We realised an ActiveX plug-in for Internet Explorer to load the paged landscape from a Web server in the browser. The final goal is to realise a system, useful for Public Administrations, Research Institutions and other public institutions, but also for the worldwide community. This system let a user not only navigate in real time through the Web even large territories, but also interact dynamically with them, adding for instance point of views, personal paths, activating or deactivating vectorial layers that can be added on the terrain, better understanding in this way the landscape.