Design of an Integrated Feature and Terrain Triangulation Algorithm for DrivingSimulation Terrain Database Generation

摘要

Terrain database generation is one of the most expensive tasks in the developmentof human-in-the-loop visual simulations. There are many factors associated with the efficiency of generating the terrain database. Automating the process of extracting from remote sensing imagery the required database primitives, and constructing detailed 3D feature models offers many challenging problems. Another problem is to simplify the terrain model by using fewer polygons without significant loss in the visual characteristics of the rendered imagery, thereby reducing the complexity of the terrain database and improving real-time rendering performance. In this paper we present two surface simplification algorithms designed for the purpose of constructing a terrain database that is optimized for driving simulation; one using a bottom-up, polygonal refinement approach, the other using a top-down, polygonal removal approach. These two algorithms are applied to terrain surfaces that include integrated, 'stitched-in' road features, and are used to generate terrain surfaces of various levels of detail. We provide a discussion on the design of these two algorithms, some experimental results of applying the algorithms to real terrain surfaces, as well as the comparison of the two approaches on the factors of height error and the distance from the road.