'Institute of Electrical and Electronics Engineers (IEEE)'
Abstract
Within this paper we discuss and present a novel modern 3D Geographical Information System (GIS) framework Project-Vision-Support (PVS). The framework is capable of processing large amounts of geo-spatial data to procedurally extract, extrapolate, and infer properties to create realistic real-world 3D virtual urban environments. The paper focuses on the generation of a novel scene-graph structure used in a number of algorithms and novel procedures for the increased rendering speeds of large virtual scenes and the increased processing capabilities as well as ease of use to manipulate a worlds worth of data. The scene-graph structure, made of two sections, depicts the spatial boundaries of the UKs Ordnance Survey (OS) scheme down to 1km2. Each 1km2 node contains the second section of the scene-graph structure, generated from the OpenStreetMap (OSM) classifications; involving buildings, highways, amenities, boundaries, and terrain. Leaf nodes contain the model mesh data. Generation of the spatial scene-graph for the UK takes 7.99 seconds for 6,313,150 nodes. The scene-graph structure allows for fast dispersal of render states, as well as scene manipulation by pre-categorising the data into branches of the scene-graph structure. Searching a node by name is evaluated using depth-first-search and breadth-first-search giving 0.000186 and 0.036914 seconds respectively within a scene-graph of 3257 nodes