Research On 3D Cloud Modeling And Rendering Methods

Virtual reality technology is an important research field in computer graphics,and the simulation technology of wind,cloud,lightning and other natural phenomena occupies a large research scope in virtual scenes.Dynamic 3D cloud simulation usually includes modeling and rendering,in which modeling determines the complexity and appearance of the cloud,while rendering is the illumination effect and fidelity of the simulated cloud.This paper conducts large-scale cloud simulation based on real meteorological data,and studies the application methods applicable to cloud simulation technology in these two aspects.The main content includes the following two aspects.In terms of modeling,a detailed three-dimensional cloud dynamic simulation method based on dissipated particle system is proposed to solve the problems of modeling appearance shape bias rules existing in the current visualization methods.Closed upper and lower surfaces were constructed to allow the WRF data-based cloud model to display a fine three-dimensional cloud shape.The improved multineighborhood tracking algorithm was used to search the boundary points of the cloud,and the Hermite curve was used to reconstruct the cloud surface.Finally,Simplex noise was added to combine with the spherical surface to carry out disturbance,so as to eliminate the regular phenomenon of cloud surface caused by the Hermite curve and present fine three-dimensional cloud surface effect.In order to simulate the cloud dissipation process in real time,dissipation functions are calculated according to the concentration distribution and particle position of three-dimensional cloud.The experimental results show that this method can be applied to cloud data modeling to further refine the cloud surface and show the dynamic cloud dissipation process while ensuring the modeling speed.In terms of rendering,a 3d cloud simulation method based on multiplicity interpolation was proposed to solve the problems of high rendering complexity and low rendering fidelity.For the analysis of sampling points in ray projection,the optical properties of sampling points and different sampling step sizes and interpolation modes are used in the threshold range to realize the speed advantage in cloud rendering.In order to show the changes of cloud illumination effect,curvature calculation method is adopted to enhance the illumination intensity of cloud,which can clearly reflect the internal structure information and external shape details of THREE-DIMENSIONAL cloud.Experimental results show that the rendering method can improve the rendering speed and enhance the illumination realism.