Development of a virtual level of detail scene graph for terrain modeling in Java3D (non-reviewed)

Summary form only given. Three-dimensional modeling of geographic information systems has become a reality due to the low cost of relatively powerful workstations, improved performance and memory capabilities of graphics hardware, and the introduction of cross-platform standards such as OpenGL and Java3d. The work presented in this paper is part of an ongoing project whose goal is to create efficient algorithms that support real-time display and fly through capabilities of large virtual world based on NASA and USGS mapping data. The size and resolution of the virtual world should not be limited to the size of RAM or even virtual memory; rather the segments should be loaded, as they are required. This requires the creation of a virtual level of detail segments (LOD) (based on Java3D geometry objects) that are dynamically retrieved as the user moves through the virtual world. To accomplish this it is necessary to have both an efficient storage and retrieval mechanisms and employ efficient rendering techniques. The algorithms employed should use a reasonable amount of disk space and does not unduly burden the network or processor. In addition to having efficient use of resources, the algorithm should minimize visual artefacts associated with LOD processing, namely gaps and checker boarding.