Research And Implementation Of Ray Tracing In Rendering Space Target And Earth Scene

With the development of space technology and advances in computer graphics, the expected effects of the space mission simulation and visualization have been growing. Ray tracing is a generic technology based on geometrical optics to generate realistic images, which uses a uniform model to simulate optical phenomena such as diffuse reflection, specular reflection and scattering at surface and transmission, refraction and attenuation at medium, to achieve complex special effects rendering such as scene blanking, shadow generation, water fluctuations and atmospheric effects. The ray tracing algorithm is introduced to render the space scene, not only can factually show the space science missions with visible light, but also can be applied to visualize scientific data with no spectral characteristics.This article studies how to organize scene data to form a special data format for accelerating ray tracing algorithm, and discusses how to change 3DS format model into basic element supported by the system.In order to generate more realistic images, this paper introduces the Mersenne Twister random perturbation to track the diffuse light, and use Beer's law to simulate the light attenuation in the semi-transparent objects and generate soft shadows according to Monte Carlo theory. Finally, it formed very realistic rendering effects.In terms of drawing atmospheric effects, this paper describes the process of Nishita single scattering model in detail, points out the lack of drawing atmospheric scattering by O'Neil, and transforms it into ray tracing mode for this rendering system.Finally, this article designs a generic, distensible ray tracing system with modular approach based on ideas of hierarchical organization and provides a basis framework for future visualization space missions.