Lazy generation of building interiors in realtime

Impenetrable doors are often quite common in virtual worlds. This is especially apparent in video games boasting large urban environments. Although there are often enterable buildings in these games, the vast majority of the buildings cannot be entered. Given limited development times and memory limitations, it is infeasible for developers to create such a large number of building interiors for the player to explore. Automatic real-time building interior generation can provide a means of entry through every visible door in a virtual world. We present a novel approach to generate virtual building interiors in real-time. Although a building in its entirety may be quite large, only the portions of the building that are needed immediately are generated. This lazy generation scheme allows the use of only a fraction of the memory that a model of the entire building requires. Our method provides realtime frame rates, making it attractive for realtime interactive applications