Aspen was filmed in early fall and winter. The user was able to "in situ" change seasons on demand while moving down the street or looking at a façade. A three-dimensional polygonal model of the city was also generated, using the Quick and Dirty Animation System (QADAS), which featured three-dimensional texture-mapping of the facades of landmark buildings, using an algorithm designed by Paul Heckbert. These computer-graphic images, also stored on the laserdisc, were also correlated to the video, enabling the user to view an abstract rendering of the city in real time.