Images for accelerating architectural walkthroughs

We describe our image-based solutions to produce a system for the interactive walkthrough of large architectural models. Our overall approach uses a specialization of impostors introduced by Maciel and Shirley (1995). With this method, portions of a general 3D model can be replaced with representations that take less time to render, namely 2D textures. Solving the general problem of deciding where to place textures to improve rendering performance proves difficult. The cells and portals framework lets us formulate a set of concrete and efficient algorithms for replacing geometry with images.