Ray-Casted BlockMaps for Large Urban Models Visualization

We introduce a GPU-friendly technique that efficiently exploits the highly structured nature of urban environments to ensure rendering quality and interactive performance of city exploration tasks. Central to our approach is a novel discrete representation, called BlockMap, for the efficient encoding and rendering of a small set of textured buildings far from the viewer. A BlockMap compactly represents a set of textured vertical prisms with a bounded on-screen footprint. BlockMaps are stored into small fixed size texture chunks and efficiently rendered through GPU raycasting. Blockmaps can be seamlessly integrated into hierarchical data structures for interactive rendering of large textured urban models. We illustrate an efficient output-sensitive framework in which a visibility-aware traversal of the hierarchy renders components close to the viewer with textured polygons and employs BlockMaps for far away geometry. Our approach provides a bounded size far distance representation...

• Type: Journal
• Year: 2007
• Where: CGF
• Authors: Paolo Cignoni, Marco Di Benedetto, Fabio Ganovelli, Enrico Gobbetti, Fabio Marton, Roberto Scopigno
• Keywords: CGF 2007, City Exploration Tasks, Size Texture Chunks, Textured Urban Models