CPU-GPU Algorithms for Triangular Surface Mesh Simplification

16 Suzanne M. Shontz and Dragos M. Nistor(a) Armadillo (b) Bunny (c) Gargoyle(d) Hand (e) Horse (f) KittenFig. 9. The resulting meshes after 10 iterations of the CPU-GPU inverse reductionalgorithm.version of an original mesh. They may also be useful for real-time visualizationof triangular surface meshes used in scientific computing applications.The simplification rate and running time of the CPU-GPU algorithmsdepended on multiple factors, including the GPU algorithm selected. BothCPU-GPU algorithms used the same amount of GPU memory for any specificCPU-GPU split, as they both needed to keep track of the same numbers ofvertices and elements on the GPU. As the GPU workload was increased, theamount of GPU memory used increased as well. For both algorithms, as thesize of a mesh increased, the decrease in simplification time increased, asthe GPU workload was increased. The simplification rate of approximately68% that the CPU-GPU marking algorithm achieved was higher than thesimplification rate of approximately 59% that was achieved by the inversereduction algorithm, over ten iterations. This slight increase in simplificationrate provided by the marking algorithm was counterbalanced by an increaseof 5.55% to 11.48% in the running time when the GPU was given the fullworkload. Further simplification is possible if the simplification algorithm wererun for a larger number of iterations. This suggests that the GPU markingalgorithm should be used when a larger simplification rate per iteration isneeded and running time is not a limiting factor. However, the GPU inversereduction algorithm should be used when time is a limiting factor or when alesser simplification rate per iteration is required, such as for smaller meshes.Our results show that certain areas of the surface mesh were repeatedlysimplified over multiple iterations, causing the meshes to look excessively simplifiedin these areas, since element ordering determines the simplification