the company Blue Sky Productions in Salem, New Hampshire, with the intention to create Underworld. Among the company's first employees was Doug Church, who was studying at the Massachusetts Institute of Technology (MIT). The team was thus composed of Doug Church as programmer, Doug Wike as lead artist and Paul Neurath as lead designer. Development began in May 1990. An early difficulty was the implementation of texture mapping. Neurath had experimented unsuccessfully with the concept on an Apple II computer in the late 1980s, but he believed that the more powerful IBM PCs of the time might be able to process it. He contacted Lerner Research programmer Chris Green—an acquaintance from his past work with Ned Lerner—who created a working algorithm. Using the Space Rogue engine, Green's algorithm, assembly code from Lerner Research's Car and Driver and original programming, the Blue Sky team completed a prototype of Underworld after roughly a month of work. Neurath described the prototype as "fast, smooth, and [featuring] true texture mapped walls, though the ceiling and floor were flat shaded and the corridors and rooms were all 10' [3.0 m] high—it looked a lot like Wolfenstein-3D in fact." The team demonstrated it at the June 1990 Consumer Electronics Show (CES) and impressed Origin Systems. Origin producer Warren Spector later said, "I remember Paul showing me that demo ... at CES and being totally floored by it. None of us had ever seen anything like it." The two companies reached a publishing agreement that summer, and Origin suggested that the game be reworked to fit into the Ultima universe. The team agreed, and the game was renamed Ultima Underworld. While Spector had hoped to produce the game, he was not assigned to the role; and he later said that he "sort of watched [the other producer] jealously from the sidelines." After the game was renamed, Doug Church recruited Dan Schmidt, a college friend who had just graduated from MIT, as a programmer. The team abandoned the Space Rogue engine and created a new one that could display a believable 3D world—one with varying heights and texture-mapped floors and ceilings. Church estimated that the first year of production was dedicated to creating the game's technological base. However, Neurath stated that the team spent "comparatively little" time on the game's technology, and that "most was spent working on game features, mechanics, and world building". Their ultimate goal was