Kurt Kühnert

Abstract

Large-scale terrain rendering in real-time is difficult and still an active topic of research. These landscapes are enormous in scale, so an effective level of detail strategy is needed. It is essential to represent the geometry and the terrain data seamlessly at various distances in order to ensure a constant visual quality free of artifacts. This paper introduces a novel terrain rendering approach that builds and improves upon state of the art methods. By using the cutting-edge Uniform Distance-Dependent Level of Detail (UDLOD) triangulation method, a seamless and effective mesh representation is produced. In order to create a dense and temporally consistent triangulated mesh, this fully GPU-based algorithm divides a quadtree covering the terrain into small tiles that can be culled in parallel and are morphed seamlessly in the vertex shader. With the proposed Chunked Clipmap, effective out-of-core paging of terrain data is made possible by combining the advantages of quadtrees and clipmaps. This data structure supports trilinear and anisotropic filtering, constant time view-dependent access, and graceful degradation in the event that data is not available. Together, these otherwise separate techniques allow for the real-time rendering of massive real-world terrains, as we will show on a dataset covering the entire Free State of Saxony at a resolution of one square meter.

Keywords