A Real-time Rendering Method of Dynamic Reflection on a Transparent Object

Many high quality rendering methods have been developed in computer graphics fields. The most basic one is ray tracing, which can generate an image including shadow, reflection and even refraction; however, it is difficult to render a complicated scene in real time. Therefore, sonic methods use image based technologies and others utilize hardware performance such as OpenGL pixel shader programming. On the reflection fields, environment mapping is usually used for the real-time rendering. However it is based on an image that is registered in advance, so that dynamic reflection, which reflects moving objects and changing light, is difficult in real time. On the other hand, interactive refraction has become available using GPU (Graphics Processing Unit) performance; however it is also based on image space, which is calculated in advance so that it is difficult for the dynamic refraction. In addition, there is no research for rendering an image reflected on a transparent object and seen through it in real time. In this paper, we present a rendering method of reflective and transmissive images in real time. In our method, instead of using environment mapping based on pre-registered images, a mirror-reversed model of the real world is generated automatically and the traditional computer graphics rendering techniques based on OpenGL is used. Our method does not depend on the environment image but depends on only CG model, so that generation of dynamic reflective and transmissive images is available in real time.