Geometry Splitting: An Acceleration Technique of Quadtree-Based Terrain Rendering Using GPU

Abstract

SUMMARYIn terrain visualization, the quadtree is the most frequently used data structure for progressive mesh generation. The quadtree provides an efficient level of detail selection and view frustum culling. However, most applications using quadtrees are performed on the CPU, because the pointer and recursive operation in hierarchical data structure cannot be manipulated in a programmable rendering pipeline. We present a quadtreebased terrain rendering method for GPU (Graphics Processing Unit) execution that uses vertex splitting and triangle splitting. Vertex splitting supports a level of detail selection, and triangle splitting is used for crack removal. This method offers higher performance than previous CPU-based quadtree methods, without loss of image quality. We can then use the CPU for other computations while rendering the terrain using only the GPU.

Bimodal Vertex Splitting: Acceleration of Quadtree Triangulation for Terrain Rendering

“…We compared the rendering speed of bimodal vertex splitting (BVS in Fig. 11), geometry splitting [7] (GS in Fig. 11), chunk level-of-detail method using ef-buffer [19] (Chunk in Fig.…”

“…Our previous work on geometry splitting [7] provides GPU-based quadtree triangulation overcomes this limitation. Figure 1 (a) shows the entire process of geometry splitting.…”

“…In geometry splitting, we used the representative error of a node δ rep at the midpoint of the patch [7]. δ rep is chosen by the maximum value between the value of the geometric errors of the patch and double the value of the representative geometric error of the child nodes.…”

“…Conventional quadtree triangulation methods are usually performed on a CPU as the pointer and recursive operation are not suitable for a GPU. In our previous research, we proposed Geometry Splitting [7], which provides parallel quadtree triangulation using a GPU in order to take advantage of recent improvements in GPUs. The vertices are split in a geometry shader in order to select the detail level of the terrain mesh, and then they are converted into regular patches (vertex splitting).…”

Vertex Propagation for Fast Ray-Casting of Digital Elevation Model

“…Due to the ever increasing size of the terrain data, previous polygonal mesh based approaches [1][2][3] have critical problems by mapping the terrain data into polygons. Even though, most mesh reconstructions were performed on CPU.…”