Terrain Rendering Techniques for the HPC-Lab Snow Simulator

Abstract

This thesis presents a technique for GPU-based terrain rendering and the changes made to the HPC-lab snow simulator to integrate the new terrain rendering technique into the simulator. Our novel terrain rendering technique combines ideas from existing terrain rendering techniques such as CDLODcite{CDLOD} and Geometry Clipmapscite{geoclipmaps} into a hybrid method. The terrain rendering works on patches of quads, that are tessellated, using hardware tessellation based on the level of detail needed. The tessellated patches are then displaced, using a vertex texture fetch of the heightmap in the tessellation shader. The implemented GPU terrain rendering technique is then added to the HPC-lab snow simulator, and changes to the simulator are implemented to facilitate the new terrain rendering technique, all of the old GLSL shaders are updated to the newest standard, the code structure is changed, and the collision detection of the snow simulator is updated to accommodate changes made to the terrain.The results from our benchmarks show that the tessellation pipeline can be used to facilitate terrain triangle count of over 16 million triangles while maintaining a stable frame rate of over 1400 FPS. When used in combination with the simulator, the implementation is still able to achieve frame rates that are vastly greater than the old implementation in the snow simulator. The visual results acheived from using Perlin noise gives the simulator a more realistic feel, while not degrading the performance of the implementation. Suggestions for futher improvements are also included.