3d Yunjing Analog Key Technologies To Achieve

With the rapid upgrading of computer hardware, especially the naissance of the Programmable Graphics Processing Unit (GPU), the software industry is undergoing tremendous change. In particular, this change is reflected in the field of computer graphics. The huge impact of the change not only affects the engineering field to help people increase the quality of their daily lives, but also creates or extends many research areas in computer science, such as volume rendering, light simulation, group animation, general computing and so on.Realistic rendering of outdoor scenes is an important portion of computer graphics, and can reflect the essence of related researches on computer graphics. In outdoor scenes, cloud plays a decisive role in atmospheric environment because of its various shapes and different colors. Cloud is one of the indicators of the weather styles and the climate changes, and is a basic element affecting flights and military operations. However, due to the uncertainty of the cloud surface and boundary ambiguity, plus the complex physical process of the formation and the various shapes over time, the modeling and drawing of the cloud has been considered one of the most challenging research topics in computer graphics. Lots of researches in different countries have been working on this area for thirty years and proposed a collection of new attempts and pioneering ideas, meanwhile, they achieve considerable advance in simulating efficiency, verisimilitude and other aspects.Applications of realistic cloud modeling and rendering are extremely widespread, but as its subject knowledge and theory involved is complex and obscure, the current practice of existing methods shows that there are somewhat shortcomings and defects. Nowadays, for satisfying the needs of the realistic simulation of the cloud in various industries, and promoting the development of the computer graphics in our country, it is very important to enhance the realism of cloud modeling and rendering in related technology research and implementation work.In chapter 2 of this thesis, the realistic simulation is present to introduce chaos theory, cloud physics, flight meteorology, atmospheric optics, atmospheric dynamics, and so on. In chapter 3, different kinds of research results in realistic cloud simulation and rendering field during the past thirty years are summarized and concluded introduce. In chapter 4, a 3D framework is proposed and implemented to improve cloud modeling and rendering based on existing theories and algorithms. In this framework, specifically, Coupled Map Lattices (CML) is adopted to generate cloud modeling datum, on which a basis illumination model based on Spherical Harmonics is implemented to obtain the light distribution. Finally, Sliced Volume Rendering based on GPU is used to draw the 3D cloud scenes.Lastly, this thesis summarizes the development of existing realistic simulation of cloud study and outlines future study. In addition, this thesis proposes some other topics worthy of further research.