With the performance and programmable flexibility of graphics processing unit (GPU) improved continuously, a growing number of computer graphics modeling and simulation works can be implemented on it. The modeling and simulation works are mainly include two aspects: one is modeling method, another is simulation and rendering. This thesis carried out innovation in both aspects. All the modeling methods in the thesis are first proposed according to specific applications. We also make the simulation and rendering on GPU to utilize its high performance and programmable flexibility. Simulation on GPU can also reduce the burden of CPU and avoid data transmission between CPU and GPU. Details of the thesis are as follows: We present a physically based modeling and simulation method for aeolian sand movement. Our method is based on the mechanical behavior of single sand grains, which is widely studied in the Physics of blown sand, but is first applied in computer graphics. We took significant mechanisms of sand transportation into our model, such as saltation, successive saltation and collapsing, while simplified the vegetation model and wind field model to make the simulation feasible and affordable. To accelerate the simulation process, we implemented the proposed method on the programming graphics processing unit. Finally, we proved that our method can reflect many characteristics of sand ripple evolution through several demonstrations. We also gave several synthesized desert scenes made from the simulated height field to display its significance on application. We present a stroke based modeling and simulation system that can generate pencil drawings both automatically and interactively. On the basis of existing works, we add some human drawing behaviors and drawings skills to our system. We also proposed a new sampling method to automatically generate hatching strokes. Compared to previous related work, the proposed sampling method is simple, and can improve rendering efficiency and utilization of sampling points. We implemented the simulation and rendering mainly on GPU to reduce the burden of CPU. This also makes large number of strokes simulation and rendering become possible. Finally, we showed that our system can fast generate realistic and vivid pencil drawing pictures. With the aid of the system, even non-professional users can fast design handcrafted pencil drawings. Compared with other image based, volume based and texture mapping based pencil d...
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