Overview of Quadtree-based Terrain Triangulation and Visualization

Real-time rendering and multiresolution modeling of triangulated surfaces has attracted growing interest over the last decade. For interactive visualization of very large scale grid digital elevation models efficiency is a particularly important aspect. The graphics rendering load must be controlled by reducing the number of rendered primitives using level-of-detail (LOD) techniques, adaptive extraction of LOD triangle meshes in main memory must be performed at interactive frame rates, and loading-on-demand of elevation data from secondary storage has to be highly efficient as well. Due to the high regularity of grid digital elevation models, hierarchical quadtree based terrain triangulation models have been shown to be among the most efficient methods available. In this paper we will survey and compare several approaches that follow this quadtree based surface decomposition and triangulation.