Real-time Simulation Of Rain And Snow In Virtual Training Scene

With the rapid development of computer technology,virtual reality technology has been widely used in military,medical,scientific research and teaching.The simulation of rain and snow environment is an important part of the virtual training scene,and it has also been paid more attention and development in virtual reality simulation.With the increasing demand for visual immersion scenes,realistic 3D rendering technology of rain and snow simulation has become a hot and difficult research,mainly in the simulation of heavy rain and heavy snow and the rendering of irregularities between individual rain and snow particles.In order to achieve real-time simulation of rain and snow environment,this paper focuses on the key technologies and methods of rain and snow simulation based on 2D texture mapping.The main contents are as follows:Firstly,this paper proposes the method of combining a fringe pattern and a noisy pattern to simulate the raindrop trajectory.Compared with the method of simulation based on individual particle rendering,the method of combing a fringe pattern and a noisy pattern proposed in this paper can achieve the simulation of raindrop trajectory and real-time simulation of heavy rain scene.Then,this paper proposes the simulation of snowflake particles based on combination of the noisy patterns with different step m.Compared with the simulation method based on particle system,the method of combing the noisy patterns with different step m proposed in this paper can simulate the individual differences among snowflake particles.Finally,this paper proposes a multi-layer rendering method,which not only enhances the irregularity of rain and snow in 2D texture,but also can simulate the perspectivity and the 3D effect based on the 2D simulation,which enhances the visual immersion.Applying this technology to outdoor simulation scenarios based on the Unity3 D and joining the simulation of rain and snow proposed in this paper in outdoor scenes without rain and snow,the loss of 3D rendering does not exceed 5 frames per second.This shows that the real-time simulation of rain and snow based on 2D texture mapping proposed in this paper can guarantee real-time rendering and a little burden on simulation.