Any virtual walkthrough of a real-life environment has to achieve the two conflicting goals of scene realism and interactive frame update rates to be able to provide a virtual reality experience. In my talk, I shall outline my work aimed at achieving these two mutually conflicting goals in a working walkthrough system. I shall give an overview of the issues involved, outline various algorithmic approaches, and demonstrate the results through video segments of a working system.
For achieving realistic view-independent global illumination we use the radiosity lighting model. I shall outline how radiosity algorithms work and how they can be implemented in parallel.
Textures enable us to represent detail at a relatively low cost in computer graphics. I shall present how the real-time procedural textures can be used to achieve scene realism while maintaining interactive frame update rates.
A multiresolution-modeling-based rendering algorithm provides an elegant way to integrate scene realism with interactivity. The main idea here is to represent objects that are perceptually more important at higher levels of detail and to represent objects that are perceptually less important at lower levels of detail. Crucial to such an approach is an algorithm that approximates given polygonal objects at varying levels-of-detail. I shall outline an algorithm that approximates polygonal objects within a user-specifiable distance $\epsilon$ from the input object and is topology preserving.
I shall conclude my talk with a brief video clip summarizing other aspects of my research that I have done in interactive three-dimensional computer graphics. These include interactively computing and displaying molecular surfaces and robust evaluation of algebraic surface intersections.