Geometry-based Mapping and Rendering of Vector Data over LOD Phototextured 3D Terrain Models

Abstract

Interactive three-dimensional (3D) visualization of very large-scale grid digital elevation models coupled with
\ncorresponding high-resolution remote-sensing phototexture images is a hard problem. The graphics load must be
\ncontrolled by an adaptive view-dependent surface triangulation and by taking advantage of different levels of
\ndetail (LODs) using multiresolution modeling of terrain geometry. Furthermore, the display of vector data over
\nthe level of detail terrain models is a challenging task. In this case, rendering artifacts are likely to occur until
\nvector data is mapped consistently and exactly to the current level-of-detail of terrain geometry. In our prior
\nwork, we have developed a view-dependent dynamic block-based LOD mesh simplification scheme and out-ofcore
\nmanagement of large terrain data for real-time rendering on desktop PCs. In this paper, we have proposed a
\nnew rendering algorithm for the combined display of multiresolution 3D terrain and polyline vector data
\nrepresenting the geographical entities such as roads, state or country boundaries etc. Our algorithm for
\nmultiresolution modeling of vector data allows the system to adapt the visual mapping without rendering
\nartifacts to the context and the user needs while maintaining interactive frame rates. The algorithms have been
\nimplemented using Visual C++ and OpenGL 3D API and successfully tested on different real-world terrain
\nraster and vector data sets.