关键词: 粒子系统, 降雪模拟, 积雪模拟, 高度场, 层次细节

Abstract: The particle system can hardly simulate the natural features effectively and real-time at the same time. Based on the analysis of traditional simulation methods, a real-time rendering algorithm was presented. The algorithm used rectangular elementary to simulate snow particles，added texture mapping based on superposition，normalized snow lifecycle for color blending，and regulated the size of snow particle and snow density according to the size of temperature. In the snow-falling stage, this algorithm introduced Level Of Detail (LOD) technology, imitated the movement effect according to the whereabouts of the snow particles moving force characteristics, took the force comprehensive consideration and simplified to reduce the computational complexity and improve the snow simulation authenticity.In the snow-accumulating stage, this method obtained the exposed surface of the scene model and its height field. And then based on a point coordinates and the point height in the field in a plane, it got the position of snow particles steadily to simulate the height change effect. This new method used the whole surface as ground-object emitter and superimposed the corresponding particle texture to improve authenticity.

Key words: particle system, falling snow simulation, accumulating snow simulation, height field, Level Of Detail (LOD)