Fountain Effect. Direct3d-based Particle System

The simulation of nature sceneries in virtual scene is an important research branch in the field of computer graphics. The nature sceneries, such as fountain,waterfall,fire,water-stream,rain,and snow, possess anomalistic,dynamic and stochastic character. It is extremely challenging to simulate these nature sceneries, since it is quite complex and difficult to model these. There are two methods to simulate these: one is based on physics modeling; another is founded on particle system modeling. The thesis adopts the latter method to research fountain effect.The effect of fountain can boost up the immersion feeling of virtual reality system, and particle system is the impactful means to implement fountain effect. Particle system is one of the main research contents in virtual scene. Some researchers simulate fuzzy and anomalistic objects by the means of particle system. Since most of the researchers make use of 3-D graphics function lib—OpenGL as drawing tool, the thesis attempts to adopt 3-D graphics function lib—Direct3D as drawing tool to simulate these anomalistic> fuzzy nature objects. And the article begins the research from several aspects:The paper discusses the technique and function of 3-D graphics function lib—Direct3D of Microsoft and probes into core device of Direct3D. We apply the point-sprite of Direct3D as particle primitive and set up the attributes of particle neatly.The paper introduces the basic principle and the implementation steps. Then we analyze nature sceneries by use of particle system.The article analyzes the hydrokinetics principle and the viscosity of fluid body. Then we bring forward the method of fake-particle-viscosity, which is based on liquid viscosity of hydrokinetics and the combination of Newton Viscosity Law and particle system. The inner friction which is calculated by Newton Viscosity Law make several particle to conglutinate up of differently big and small water-beads, which can simulate the true effect of fountain. We analyze the fountain body by making use of the technique of particle system, then analyze the motion of true-life fountain by bringing to bear hydrokinetics principle. And we construct the model of fountain particle system by the means of particle system modeling, then do some research about the generation,the motion and the death of water-bead particle of the fountain. Finally, we implement the 3-D effect of fountain in the platform of Direct3D by adopting the method of fake-particle-viscosity and the modeling of fountain particle system.