Interactive Landscapes Reconstruction: a Web 2D and 3D OpenSource solution

The paper will focus on a novel desktop and web-based VR system based on OpenSource tools. The system lets a user to navigate in large territories, in real time and through the Web. It allows a dynamical interaction with geographical data and 3d models, adding points of view or personal paths, activating or deactivating thematic layers that can be viewed directly on the terrain. In this way it’s quite easy to share data and information (at research level) and also to better understand the landscape (at user level). The system realised is based on two open projects: OpenSceneGraph library and Virtual Terrain Project. They were used in combination, modifying or producing new parts of their code and adding plug-ins, in order to create a tool useful to reconstruct complex landscapes, starting from GIS data (DEM, GeoImages and vector data). With these data it’s possible to build a three-dimensional terrain through a tool, OSGdem, that generates paged and hierarchical 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. and inserting them even directly on the scene, at a certain geographical co-ordinate. We then implemented OSG potentialities of .ive files publication over the Web, allowing VT Enviro to export the modified landscape. An ActiveX plug-in was built for Internet Explorer to load the paged landscape from a Web server in the browser.