Improvement In The Real-Time Simulation Of Realistic Smoke

simulate the natural scenery as vivid as possible by computer. The smoke simulation has a wide range of applications in movie effect, military simulation and computer game and so on. In recent years, with the development and improvement of the computer graphics technology, the realistic effect and real-time quality are more and more important for the users. Traditional particle system and texture mapping method are hard to meet the user's requirement, while the physical model occupate too much computational resource. So this paper focused on the following areas aiming to seek for a tradeoff between the realistic effects and real time performance.Firstly, focusing on the real-time quality of the particle system and the realistic performance of the phisical model, this paper proposes a new combination of the particle system and the physical model. Firstly, the coarse particle system with appropriate particle numbers is used to describle the general trajectory of the smoke. Then, the smoke particles in three-dimensional space are projected onto a series of two-dimentional planes parallel to the view plane. Finally, we utilize the projected particels as the smoke resource to solve the Euler equation with MacCormack method on two-dimentional planes, in order to reproduces the details of high accuracy smoke and obtain the smoke effect picture more realistic.Secondly, due to meet the real-time requirement of smoke simulation in the large-scale virtual scene, this paper presents a new smoke rendering technique called view-point driven real-time smoke rendering. First, a distance function is built, which stands for the distance between the view-point and the smoke model. Second, the 3D smoke data are projected onto a series of 2-dimentional planes which are parallel to the view plane according to the distance function value. The distance function value also decides whether the smoke turbulent details are compensated back to the smoke field or not. We use the programmable hardware to rapidly compensate the turbulence back to the simulation field and render the smoke density field. The view-point driven real-time smoke rendering is proposed for the large-scale and complicated vitual scene, the rendering procedure and computational time are reduced and the requirement of the real-time is satisfied according to the optimization.Finally, the real-time simulation system of the realistic smoke was designed and realized to validate the effectiveness of the methods proposed. This smoke simulation system was designed by VC++, OpenGL and Cg.