Simulation Of The Reflective Characteristics Of The Material Based On Measured Data

Realistic material rendering is of great importance in many applications of computer graphics. In order to realize realistic rendering, the lighting conditions, the geometric construction and the reflective characteristics need to be precisely described. Although 3D geometric modeling have made great progress in recent years, precisely modeling the reflective behavior of the material still remains a critical challenge.The reflective characteristics of the material are usually defined by BRDF(Bidirectional Reflectance Distribution Function). Extensive research on the reflective characteristics of the material can be divided into three categories: analytic models, material measurement and material simulation. This paper mainly focuses on how to use measured data to realize realistic material rendering.First, the definition of BRDF is introduced and various BRDF models are compared and discussed. Next, the acquisition method of reflection data is presented and the method with which measured data can be fitted into an analytic model is mainly studied, including the model representation, the optimization algorithm and the fitting strategy. Then, the real-time reflective computation method based on GPU programming is analyzed, and the simulation process of the reflective characteristics is discussed. Finally, based on the programmable graphics rendering pipeline of GPU(Graphics Processing Unit), realistic material rendering is accomplished in the OGRE rendering engine by utilizing the fitted reflection model derived from the measured data. The process of using measured data to realize realistic material rendering is modeled in this paper. The problems involved in the fitting process and the rendering results are analyzed and discussed.