A Quantitative Analysis of Culling Techniques for Real-time Rendering of Digital Elevation Models

Abstract

The paper is concerned with investigation of effects of culling techniques on quality and smoothness of terrain data visualization within a 3D interactive environment. We utilize the Real-Time Optimally Adapting Mesh (ROAM) approach, extended with a number of efficient techniques such as implicit coordinates method within the patch array representing ROAM and the viewpoint dependent triangle rendering method for dynamic level of detail (LOD) updates. The method, which allows dynamic and interactive first person view, is combined with the View Frustum culling, the Backface culling and an original Relational Position Culling. Standard error metrics are used to verify the rendering consistency. The experimentation is conducted on two data sets representing simple gradual contour changes (Susanville, California) and complex steep contour changes (Kluane National Park, USA). Based on the results, applicability of each of the culling techniques to terrain model is discussed.