Development of Doom

The making of Doom, id Software's video game released on December 10, 1993, began in late 1992. Doom raised the bar for realism in video games with its then-advanced 3D graphics—central to its success was the new game engine by John Carmack, whose main advances included texture mapping of all surfaces, variable light levels, and floors at varying altitude. The world in Doom materialized through the level design of John Romero, Sandy Petersen and Tom Hall and the artwork of Adrian Carmack, Kevin Cloud and Gregor Punchatz.

Doom evolved significantly during its development. Originally planned to feature an intricate plot, its gameplay instead gradually turned to focus on fast action and violence. Conflicts surrounding this development led to the resignation of Tom Hall, who had written the Doom Bible, the game's initial design document.

Following the successful release of Wolfenstein 3D in May 1992, most of the id Software team set out to finish the sequel Spear of Destiny. Since this game used the same game engine as Wolfenstein 3D, lead programmer John D. Carmack could use the time to do technology research for the company's next-generation graphics engine. One of Carmack's early experiments was the Shadowcaster engine. With significant effort, choosing to isolate himself from the rest of the team for a long period of time in order to avoid distractions, he implemented various new features, including diminishing light and texture-mapped floors and ceilings and sloping floors. The Shadowcaster engine's "speed was about half that of Wolfenstein, but since this was an adventure game, built on exploration, it seemed appropriate to have a steadier pace." For Doom, Carmack implemented dynamic diminished lighting and a sector based map system (as opposed by the grid map systems of the Wolfenstein 3D and Shadowcaster engines) with wall angles other than 90°.

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