Dong, Zhao:
Visually Pleasing Real-time Global Illumination Rendering for Fully-dynamic Scenes

zhaodongmpii@gmail.com
Universität des Saarlandes, Saarbrücken, Germany
Naturwissenschaftlich-Technische Fakultäten
March 3, 2011

Abstract

Global illumination (GI) rendering plays a crucial role in the photo-realistic rendering of virtual scenes. With the rapid development of graphics hardware, GI has become increasingly attractive even for real-time applications nowadays. However, the computation of physically-correct global illumination is time-consuming and cannot achieve real-time, or even interactive performance. Although the real-time GI is possible using a solution based on precomputation, such a solution cannot deal with fully-dynamic scenes. This dissertation focuses on solving these problems by introducing visually pleasing real-time global illumination rendering for fully-dynamic scenes.
To this end, we develop a set of novel algorithms and techniques for rendering global illumination effects using the graphics hardware. All these algorithms not only result in real-time or interactive performance, but also generate comparable quality to the previous works in off-line rendering. First, we present a novel implicit visibility technique to circumvent expensive visibility queries in hierarchical radiosity by evaluating the visibility implicitly. Thereafter, we focus on rendering visually plausible soft shadows, which is the most important GI effect caused by the visibility determination. Based on the pre-fltering shadow mapping theory, we successively propose two real-time soft shadow mapping methods: "convolution softshadow mapping" (CSSM) and "variance soft shadow mapping" (VSSM). Furthermore, we successfully apply our CSSM method in computing the shadow effects for indirect lighting. Finally, to explore the GI rendering in participating media, we investigate a novel technique to interactively render volume caustics in the single-scattering participating media.

real-time rendering, real-time global illumination, implicit visibility, instant radiosity,  shadow mapping, soft shadows, prefiltering shadow maps, convolution soft shadow map,  variance soft shadow map, indirect lighting, volume caustics, participating media rendering