Development of Doom

In May 1992, id Software released Wolfenstein 3D. It is often referred to as the "grandfather" of first-person shooters,[4][5] setting expectations for fast-paced action and new technology, and greatly increased the genre's popularity.[4][6][7][8] Immediately following its release, most of the team began work on a set of new Wolfenstein episodes, Spear of Destiny. As the episodes used the same game engine as the original game, id co-founder and lead programmer John Carmack instead focused on technology research for the company's next game, just as he had experimented with creating a 3D game engine prior to the development of Wolfenstein 3D. Between May and Spear of Destiny's release in September 1992, he created several experimental engines, including one for a racing game, before working on an enhanced version of the Wolfenstein engine to be licensed to Raven Software for their game ShadowCaster. For this engine, he developed several enhancements to the Wolfenstein engine, including sloped floors, textures on the floors and ceilings in addition to the walls, and fading visibility over a distance. The resulting engine was much slower than the Wolfenstein one, but was deemed acceptable for an adventure game like ShadowCaster.[9]

Following the release of Spear of Destiny and the completion of the ShadowCaster engine, id Software discussed what their next game would be. They wanted to create another 3D game using Carmack's new engine as a starting point, but were largely tired of Wolfenstein. Lead designer Tom Hall was especially weary of it, and pushed for the team to make another game in the Commander Keen series; the team had created seven episodes in the series in 1990–91 as their first games, but the planned third set of episodes had been dropped in favor of Wolfenstein 3D. While Carmack was initially interested in the idea, the rest of the team was not. They collectively felt that the platforming gameplay of the series was a poor fit for Carmack's fast-paced 3D engines, and especially after the success of Wolfenstein were interested in pursuing more games of that type. Additionally, the other two co-founders of id were not interested in creating another Keen game: John Romero, the designer of Wolfenstein, was not interested in doing another "cutesy" game, and lead artist Adrian Carmack preferred to create art in a darker style than the Keen games. John Carmack soon lost interest in Keen idea as well, instead coming up with his own concept: a game about using technology to fight demons, inspired by the Dungeons & Dragons campaigns the team played, combining the styles of Evil Dead II and Aliens.[9][10] The concept originally had a working title of "Green and Pissed", which was also the name of a concept Hall had proposed prior to Wolfenstein, but Carmack soon named the proposed game after a line in the film The Color of Money: "'What's in the case?' / 'In here? Doom.'"[9][11]

The team agreed to pursue the Doom concept, and development began in November 1992.[10] The initial development team was composed of five people: programmers John Carmack and John Romero, artists Adrian Carmack and Kevin Cloud, and designer Tom Hall.[12] They moved offices to a dark office building, which they named "Suite 666", and drew inspiration from the noises coming from the dentist's office next door. They also cut ties with Apogee Software, who had given them the initial advance money for creating their first game, Commander Keen in Invasion of the Vorticons, and through which they had published the shareware versions of their games to date. While they had a good personal relationship with owner Scott Miller, they felt that they were outgrowing the publisher. Cloud, who was involved in id's business dealings, pushed for id to take over shareware publishing duties themselves after investigating and finding that Apogee was unable to reliably handle the volume of customers buying id's games through Apogee. He convinced the others that the increased sales revenue would make up for the problems of handling their own publishing. The two companies parted amicably, and Doom was set to be self-published.[13]

John Romero in 2012

Early in development, rifts in the team began to appear. Hall, who despite having wanted to develop a different game remained the lead designer and creative director for the company, did not want Doom to have the same lack of plot as Wolfenstein 3D. At the end of November he delivered a design document, which he named the Doom Bible, that described the plot, backstory, and design goals for the project.[10] His design was a science fiction horror concept wherein scientists on the Moon open a portal from which aliens emerge. Over a series of levels the player discovers that the aliens are demons; Hell also steadily infects the level design as the atmosphere becomes darker and more terrifying.[14] While Romero initially liked the idea, John Carmack not only disliked it but dismissed the idea of having a story at all: "Story in a game is like story in a porn movie; it's expected to be there, but it's not that important." Rather than a deep story, John Carmack wanted to focus on the technological innovations, dropping the levels and episodes of Wolfenstein in favor of a fast, continuous world. Hall disliked the idea, but Romero sided with Carmack. Although John Carmack was the lead programmer rather than a designer, he was becoming seen in the company as the most important source of ideas; the company considered taking out key person insurance on Carmack but no one else.[14]

Hall spent the next few weeks reworking the Doom Bible to work with Carmack's technological ideas, while the rest of the team planned how they could implement them.[10] His adjusted vision for the plot had the player character assigned to a large military base on an alien planet, Tei Tenga. At the start of the game, as the first of four player character soldiers, named Buddy, played cards with the others, scientists on the base accidentally open a portal to Hell, through which demons poured through, killing the other soldiers. He envisioned a six episode structure with a storyline involving traveling to Hell and back through the gates which the demons used, and the destruction of the planet, for which the players would be sent to jail.[14][15] Buddy was named after Hall's character in a Dungeons & Dragons campaign run by John Carmack that had featured a demonic invasion.[14] Hall was forced to rework the Doom Bible again in December, however, after John Carmack and the rest of the team had decided that they were unable to create a single, seamless world with the hardware limitations of the time, which contradicted much of the new document.[10]

At the start of 1993, id put out a press release by Hall, touting Buddy's story about fighting off demons while "knee-deep in the dead", trying to eliminate the demons and find out what caused them to appear. The press release proclaimed the new game features that John Carmack had created, as well as other features, including multiplayer gaming features, that had not yet been started on by the team or even designed.[14] The company told Computer Gaming World that Doom would be "Wolfenstein times a million!"[16] Early versions were built to match the Doom Bible; a "pre-alpha" version of the first level included the other characters at a table and movable rolling chairs based on ones at the id office.[17] Initial versions also retained "arcade" elements present in Wolfenstein 3D, like score points and score items, but those were removed early in development as they felt unrealistic and not in keeping with the tone.[12] Other elements, such as a complex user interface, an inventory system, a secondary shield protection, and lives were modified and slowly removed over the course of development.[10][18]

Sandy Petersen in 2004

Soon, however, the Doom Bible as a whole was rejected: Romero wanted a game even "more brutal and fast" than Wolfenstein, which did not leave room for the character-driven plot Hall had created.[14] Additionally, the team did not feel that they needed a design document at all, as they had not created one for prior games; the Doom Bible was discarded altogether.[14] Several ideas were retained, including starting off in a military base, as well as some locations, items, and monsters, but the story was dropped and most of the design was removed as the team felt it emphasized realism over entertaining gameplay. Some elements, such as weapons, a hub system of maps, and monorails later appeared in later Doom or id games.[15] Work continued, and a demo was shown to Computer Gaming World in early 1993, who raved about it. John Carmack and Romero, however, disliked Hall's military base-inspired level design. Romero especially felt that while John Carmack had originally asked for realistic levels as they would make the engine run quickly, that Hall's level designs were uninspiring.[14] He felt that the boxy, flat levels were too similar to Wolfenstein's design, and did not show off everything the engine could do.[19] He began to create his own, more abstract levels, beginning with a curving staircase into a large open area in what became the second level of the final game, which the rest of the team felt was much better.[14][19]

Hall was upset with the reception to his designs and how little impact he was having as the lead designer; Romero has since claimed that Hall was also still uninterested in the Doom concept at all.[14][17] Hall was also upset with how much he was having to fight with John Carmack in order to get what he saw as obvious gameplay improvements, such as flying enemies.[10] The other developers, however, felt that Hall was not in sync with the team's vision for the game and was becoming a problem.[20] He began to spend less time working in the office, and in response John Carmack proposed that he be fired from id. Romero initially resisted, as it would mean that Hall would not receive any proceeds, but in July he and the other founders of id fired Hall, who went to work for Apogee.[14] Hall was replaced in September, ten weeks before Doom was released, by game designer Sandy Petersen, despite misgivings over his relatively high age of 37 compared to the other early-20s employees and his religious background.[21][22] Petersen later recalled that John Carmack and Romero wanted to hire other artists instead, but Cloud and Adrian disagreed, saying that a designer was required to help build a cohesive gameplay experience. They relented and Petersen was hired.[23] The team also added a third programmer, Dave Taylor.[24] Romero directed Petersen to revise Hall's levels with as many changes as he saw fit in order to meet his guidelines for what made for interesting levels.[20] Petersen and Romero designed the rest of the levels for Doom, with different aims: the team felt that Petersen's designs were more technically interesting and varied, while Romero's were more aesthetically interesting.[22] Romero's level design process was to build a level or part of a level, starting at the beginning, then play through it and iterate on the design, so that by the time he was satisfied with the flow and playability of the level he had played it "a thousand times". The first level, made by Romero, was the last created, intended to show off the new elements of the engine.[12] The ending screen of each level, like in Wolfenstein 3D, displays a "par time" for the level, as set by Romero.[17]

In late 1993, a month before release, John Carmack began to add multiplayer to the game, first teaching himself computer networking from a book.[20] After the multiplayer component was coded, the development team began playing four-player multiplayer games matches, which Romero termed "deathmatch"; he proposed adding a cooperative multiplayer mode as well.[25] Cloud named the act of killing other players "fragging".[20] According to Romero, the deathmatch mode was inspired by fighting games. The team frequently played Street Fighter II, Fatal Fury and Art of Fighting during breaks, while developing elaborate rules involving trash-talk and smashing furniture or equipment. Romero later stated that "you could say that Japanese fighting games fueled the creative impulse to create deathmatch in our shooters".[26]