This project aims to explore new interaction possibilities with virtual cities, including, for example, the changing of the urban geometry or the navigation within the city.
We performed our research using a VRML model of Lisbon, which we kindly obtained from Jose Dionisio, Instituto Superior Tecnico, DEM/SAE, Lisbon.
The VR software "VirtualDesign II" by Vrcom running under Linux is used for visualization.
The software can be extended by plug-ins, carrying out the interaction with the virtual city.
As input devices a spacemouse, a data glove (Immersion), a head-mounted display (Virtual Research), and a electromagnetic tracking system (Polhemus) are used.
See below for a few videos
With the plug-in findpath, the shortest path within a city can be calculated and visualized. As virtual city models generally don't include any information about the course of the streets, we extract a street graph from the VRML geometry. | |
To that end, the floor plans of the houses are calculated first (red). | |
Second, a generalized Voronoi diagram is computed from these 2D polygons with the help of the software VRONI. (blue) | |
The result is a coherent graph, representing the course of the streets. Using Dijkstra's algorithm, which has been implemented with a Fibonacci-Heap from Shane Saunders, the shortest path can be searched in this graph (green). | |
The way viewed from the street. The green balls mark the Voronoi nodes. |
Lineup (also showing the interaction utilizing the above mentioned VR devices. 5 MB).
Findpath (5 MB).
Multimove (5 MB).
Gabriel Zachmann