(An) adaptive scene processing for the real-time visualization of large scale terrain data

Abstract

This dissertation describes the real-time rendering techniques to efficiently deal with the large scale of terrain data, which make an orientation-invariant and a view frustum scale-invariant smooth rendering possible while maintaining the image quality. For an out-of-core terrain visualization on a resource-limited computing environment like a low-end graphics system or even a portable system, the real-time continuous rendering must be crucial to give people a higher level of visual fidelity. Such bulky and high resolution terrain data often arises from the progressive development of satellite technologies. And the need for visual realism is getting higher and higher. Terrain-based flight simulation tends to be essential for a large class of game and simulation applications including flight training simulation, mission planning and rehearsal, 3D situation assessment, and GIS(Geographic Information System). Most of the existing techniques often suffer from overloading massive terrain data on the-fly, especially texture data, by an abrupt rotational movement or a geo-reference to an arbitrary direction to the course of action around a viewpoint and a reasonably large viewing volume, which results in severe fluctuation in rendering performance and therefore can not guarantee the conservative frame rate. Since most researches seem to have focused on developing and enhancing parts of either the data paging/caching scheme from a hard disk or a network server or the scene processing of a polygon mesh construction(CPU-bound work) and texture management (GPU-bound work), we learned that the local benefits from those methods can not be fully utilized because they are not feasibly correlated to the other modules in the overall rendering processes. In this dissertation, we pursue the efficiency of the whole rendering processes by a consistent and coherent design of the rendering modules which appears the consistent data flow control from hard disk to the main memory...