Seamless Patches for GPU-Based Terrain Rendering

摘要

In this paper we present a novel approach for interactive rendering of large terrain datasets which is based onsubdividing the terrain into rectangular patches at different resolutions. Each patch is represented by fourtriangular tiles which can be at different resolutions; and four strips which are used to stitch the four tiles in aseamless manner. As a result, our scheme maintains resolution changes within patches and not across patches.At runtime, the terrain patches are used to construct a level of detail based on view-parameters. The selectedlevel of detail only includes the layout of the patches and the resolutions at boundary edges. Since adjacentpatches agree on the resolution of common edges, the resulted mesh does not include any cracks or degeneratetriangles. The GPU generates the meshes of the patches by using scaled instances of cached tiles andassigning elevation for each vertex from the cached textures. Our algorithm manages to achieve qualityimages at high frame rates while providing seamless transition between different levels of detail.