Doom 3

Doom 3 is a sci-fi horror fantasy first-person shooter computer game developed by id Software and published by ActiVision.

Set on November 15 and 16, 2145 in the UAC research center on Mars, Doom 3 is a re-imaging/reboot of the original Doom, with a completely new game engine and graphics.

Doom 3 had a long development schedule dating back to 2000, with a well-received demonstration at E3 in 2002, 2003 and 2004. The game was finally released in August of 2004.

The game was developed for Windows and ported to Linux in 2004; five months later, it was also released for Mac OS X (ported by Aspyr) and Xbox (co-developed by Vicarious Visions). The Xbox version is graphically similar to (although less detailed than) the original and features an additional two-player online co-operation mode. An expansion, Doom 3: Resurrection of Evil, developed by Nerve Software and co-developed by id Software, was released on April 4, 2005, and released several months later for Xbox as well. A Doom movie, loosely based on the franchise, was released roughly six months later on October 21, 2005.

Doom 3 focuses on slow methodical gameplay, as opposed to the “run and gun” feel as its predecessors. It received a positive reception for its fear inspiring atmosphere and groundbreaking graphics, but it was criticized mainly for its otherwise simplistic gameplay and clichéd horror effects.

The source code for Doom 3 was released under the GPL.

Features
According to John Carmack, the lead graphics engine developer at id, the "tripod of features" in Doom 3 technology is:
 * Unified lighting and shadowing
 * Complex animations and scripting that show off real-time, fully dynamic per-pixel lighting and stencil shadowing.
 * GUI surfaces that add extra interactivity to the game

The key advance of the Doom 3 graphics engine is the unified lighting and shadowing. All 3D engines up to and including Quake III and Unreal Tournament had computed or rendered lightmaps during map creation, saving that information in the map data, which made the lighting extremely static. By contrast in the new Doom 3 engine, most light sources are computed on the fly. This allows lights to cast shadows even on non-static objects such as monsters or machinery, which was impossible with static lightmaps. A shortcoming of this approach is the engine's inability to render soft shadows and global illumination.

As well as dynamic lighting and shadows, the Doom 3 engine was id Software's first to make extensive use of bump mapping.

To create a more movie-like atmosphere, id interspersed the gameplay with many in-game animated sequences of monsters ambushing the player or just lurking around.

To increase the interactivity with the game-world, id designed hundreds of high-resolution animated screens for in-game computers. Rather than using a simple "use key", the crosshair acts as a mouse cursor over the screens allowing the player to use a computer in the game world. This allowed an in-game computer terminal to perform more than one function, such as a readily apparent door-unlocking button, combined with a more obscure function allowing an astute player to unlock a nearby weapons locker.

Other important features of Doom 3 engine are normal mapping and specular highlighting of textures, realistic handling of object physics, dynamic, ambient soundtrack and multi-channel sound.

Hardware requirements
A disadvantage of id Tech 4 was that it needed a high-end graphics processing unit (GPU), which was at least DirectX 8.0 compliant with fully programmable vertex and pixel shaders, such as the Nvidia GeForce 3 or ATI Radeon 8500, with 64 MB of VRAM. By E3 2002, the recommended GPU was the Radeon 9700; while its DirectX 9.0 features are not necessary to render the game, its advanced architecture, 256-bit memory bus, and efficiency were needed to run Doom 3 at high detail and playable speed.

id Tech 4 resulted in the obsolescence of DirectX 7.0 graphics chips such as the widespread GeForce 2 and Radeon 7200, as well as DirectX 6.0 chipsets such as RIVA TNT2 and Rage 128, and software rendering (with an integrated Intel GMA). Owners of pre-DirectX 8.0 cards were able to use a powerful CPU to compensate for the lack of hardware Transform, clipping, and lighting (T&L) in DirectX 7.0 titles, however DirectX 8.0 calculations were far too complex for a DirectX 7.0 card or a fast CPU. While John Carmack initially warned gamers not to purchase the GeForce 4 MX (which was an improved GeForce 2), its somewhat widespread adoption compelled id Software to enable Doom 3 to run on these cards, making it the only DirectX 7.0 chip capable of running Doom 3. Some have gotten Doom 3 to run on unsupported cards such as a 3dfx Voodoo2, however this video chipset was incapable of rendering anything beyond the polygons and textures, such as the per-pixel lighting and bump mapping.

id Software pointed out that the original Doom and Doom II had gamers moving from their 386s to 486s, while the first Quake had them switching to Pentium processors. They hope that Doom 3 would do the same in getting the masses to adopt DirectX 8.0 hardware. However, from 2001-2003, DirectX 8.0 capable video cards were extremely expensive, never spawning a mass market version like their DirectX 7.0 predecessors, putting them out of the range of all but the most hardcore gamers. For instance, the GeForce 3 and GeForce 4 Ti lines never spawned mainstream versions, while the Radeon 8500's mass-market derivative in the Radeon 9000 did not have the best performance.

Development
In June 2000, John Carmack announced the start to a remake of Doom using next generation technology. This plan revealed controversy had been brewing within id over the decision.

Kevin Cloud and Adrian Carmack, two of id Software's owners, were always strongly opposed to remaking Doom. They thought that id was going back to the same old formulas and properties too often. However, after the warm reception of Return to Castle Wolfenstein (which was originally a remake of Wolfenstein 3D) and the latest improvements in rendering technology, most of the employees agreed that a remake was the right idea and confronted Kevin and Adrian with an ultimatum: "Allow us to remake Doom or fire us" (including John Carmack). After the reasonably painless confrontation (although artist Paul Steed, one of the instigators, was fired in retaliation), the agreement to work on Doom 3 was made.

The game was in development for 4 years. In 2001, it was first shown to the public at Macworld Conference & Expo in Tokyo during the unveiling of Nvidia's GeForce 3, with Apple CEO Steve Jobs introducing John Carmack on stage, who showed off a few new screenshots of id Tech 4, including some from the Doom 3.

It was later demonstrated at E3 in 2002 using an ATI Radeon 9700, where a 15-minute gameplay demo was shown in a small theater. It won awards at E3 that year. It starts off with Dr. Betruger (with spectacles) pushing his way past a couple security guard to initiate a test run. However, computer systems starting going haywire and evil spirits were released from a portal. One guard is possessed by the spirit and briefly lifted into the air, with his skin shriveling up and his goggles/visor exploding as he is transformed into a mindless zombie. After a brief vision of hell, the movie cuts to a nameless marine, taking the player's first-person shooter view. The player kills various zombies, imps, and commandos, before running out of ammo and being killed by a Hell Knight, who then rips off the player's head (the camera view) and eats it. One memorable scene is when a Pinky Demon is eating the intestines of a Fat Zombie in the bathroom.

At the same time of the E3 2002 demo showing, a downloadable film made by Fountainhead Entertainment was released, called Doom III: The Legacy, which contrasted Doom/Doom II with the new Doom III and featured interviews with key id Software staff.

Some speculated that id software was targeting the 2002 holiday season, although others believed a 2003 release date would be more realistic. After E3 2002, there was no further press release from id Software regarding the project; the company's website only had Return to Castle Wolfenstein as the latest game.

Next year, a new trailer was shown at E3 2003 and soon afterwards the id software homepage was updated to showcase Doom 3 as an upcoming project but it was also announced that Doom 3 would not be ready for the 2003 holiday season. According to some comments by John Carmack, the development took longer than expected. Originally, the game was planned for release around the same time as another highly anticipated game, Half-Life 2, in Christmas 2003. Doom 3, Half-Life 2, and Halo 2 were considered among the most anticipated games since their announcements in 2001/2002, though all three of them would not make the planned 2003 holiday season.

Doom 3 achieved gold status on July 14, 2004, and a Mac OS X release was confirmed the next day on July 15, 2004. Doom 3 was released in the U.S. on August 3, 2004. Additionally, a Linux version was released on October 4, 2004. Due to high demand, the game was made available at select outlets at midnight on the date of release. The game was released to the rest of the world on August 13, 2004 (except for Russia and other countries of the former Soviet Union, where official localization was delayed and caused the game to be released about four months later, on December 10, 2004).

Plot
Prior to the events of the game, the UAC's original project involving the exploration of Mars was to transform it into a habitable planet with the creation of Hydrocon and a breathable atmosphere.

However, the initial construction of Mars City accidentally unearthed underground artifacts and structures that revealed the existence of an ancient Martian civilization. In response, the UAC modified its original project on Mars to function as an Archeological Excavation Site, with labs and general posts established in different locations. The explorations of the caverns in 2104 led to the discovery of ancient artifact codenamed U1, the Soul Cube, along with stone tablets written by the ancient Martian civilization.

The tablets contained knowledge and technical information on a powerful teleportation technology. As a result of these discoveries, the UAC's primary goal on Mars changed to the recreation of the technology, with the supervision of UAC's brightest scientist and creator of the Hydrocon, Dr. Malcolm Betruger. The development began in the secured location known as Delta Labs. At the same time, scientists like Pierce Rogers were in charge of the archeological effort, mainly with the translation of the glyphs contained on the stone tablets. These glyphs warned of the potential risks of using the teleportation technology, which was the reason why the Martian civilization became extinct.

Once activated, the teleportation technology wasn't exactly a teleportation, it worked as portal device which led into another dimension. After several tests with cameras and animal subjects, the scientists discovered that this dimension was filled with sweltering heat and hideous creatures. Betruger and other Delta Labs personnel immediately began to try to explore this dimension using human subjects. However, many of the people that returned from the tests suffered from immense psychological trauma which lead to their deaths, many others not returning at all. As the tests occurred, the scientists at Site 3 were already translating the warning, but by the time they discovered the horrors of what happened with the Martian civilization, it was already too late. The teleportation project had already become focused on exploring and exploiting the other dimension discoveries, such as bringing back dead and live species and long travel on the dimension. Not long after, the whole Mars Base started having strange problems with light and energy, several personnel reporting frightening situations and asking for transfers off Mars.

Betruger himself became obsessed with the other dimension, becoming corrupted by the power and authority he held, using it to control Mars City and hide the horrors of his discoveries from Earth. Delta Labs scientists such as Ian McCormick and Jonathan Ishii were already theorising that the dimension was, in fact, Hell, but they were too scared to send their theories to Earth. One scientist however, named Dr. Elizabeth McNeil, challenged Betruger's authority and called the UAC Board to stop the Delta Labs project. Discovering this, Betruger expelled McNeil from Mars, and, not long after, he entered into the portal himself. When he came back, he was a different person. A couple of days later, the UAC Board of Directors on Earth appointed the company's lawyer and councilor Elliot Swann and his bodyguard Jack Campbell to enact "damage control" for the whole Mars operation. On the date of Monday November 15, 2145, they arrived at 6:18am that morning at Mars City on the ship Darkstar. The ship leaves at 18:55MST (6:55pm) bound for Burns Flat, Oklahoma, Earth and is estimated to arrive on December 27th, 2145 at 13:00CST (1:00pm)

The protagonist is, once again, an unnamed space marine holding the rank of Corporal who came along with Swann and Campbell aboard the Darkstar. This marine was called to replace another who died during an operation. As he is assigned by Master Sergeant Kelly, a.k.a “Sarge”, to find a missing scientist named Jonathan Ishii who was last seen in the old Communications Facility, Councilor Swann and Campbell argue with Betruger about the many incidents happening throughout the base, along with frightened employees and rumors of what is happening in the Delta Labs. Betruger replies to Swann that "amazing things will happen here soon," and to stay out of his way.

When the Marine finds Ishii, he babbles about sending out a warning to Delta Labs - Level 4 and that "the Devil is real. I know, I built his cage." With those words, Hell erupts from the main experimental gateway, sending a shock wave through the complex, along with glowing pentagrams and scores of evil ghost skulls that transform 90% of UAC personnel into zombies, including Ishii. The remaining staff are killed off by the attacking demons with only a few scattered squads remaining, Bravo Team being the main one. After returning to the Reception area, the Marine is ordered by Sarge to regroup with Bravo Team and help them send a distress signal to the space fleet. When the marine takes the elevator to Administration, he overhears Swann arguing with Betruger in a video phone conference, Betruger being rather calm about the situation, and claiming that it is under control. Knowing that Betruger is somehow linked to the invasion, Swann and Campbell also go to the Communications Facility to prevent anyone else from coming to Mars.

The Marine's effort to regroup with any remaining marines ends in vain as Hell has hit hard, killing or possessing the human population on Mars and leaving only a handful of humans who, with futile effort, hide or lock themselves in the most secure areas that they can reach. Passing through the Administration and Alpha Labs areas, the Marine encounters many demons and zombie enemies, some of which are lead by a powerful Vagary. After reaching the EnPro Facility, the Bravo Team is attacked and killed by a group of Imps, with the exception of one surviving marine who plays dead to hide the distress card from Swann and Campbell when they pass by him. When the Marine reaches the slaughter of Bravo Team, this survivor gives the distress card to him and is later killed by a Wraith. When the Marine finally reaches Communications, however, Campbell has already destroyed the main console with his BFG 9000. Sarge orders the Marine to go to the isolated satellite tower and send the transmission for reinforcements. There the Marine is confronted with a moral decision when Swann contacts him on a video conference, Swann asks the marine to stop the transmission since they "...don't know what the hell is going here, and until we do, this facility will remain on UAC control".

Sending the message or not, the Marine is ordered by Swann/Sarge to go to Delta Labs and help stop the invasion. After receiving security clearence to the Monorail, he is trapped by Betruger himself on the Waste Recycling Center. Betruger taunts the Marine, revealing that he commands the monsters that have overrun the base and saying that he already sent a transmission to the fleet, and he is waiting for them to show up to hijack their spaceships and attack Earth. Betruger also uses his powers to transform wounded marines into his Commando servants. After escaping the Environmental Reprocessing Center, the Marine uses the monorail and finally reaches the Delta Labs.

While at Delta Labs, the Marine meets Sarge on another video conference (after restoring power to the sector due to a missing DataLinker), Finding out that he has changed, his personality having grown cold and dark. They agree to meet in the Delta Service Tunnel, but Sarge doesn't show up. On the Delta Labs - Level 2, the Marine encounters Ian McCormick, who explains to him the background story about the teleportation experiments and the Hell invasion, and helps the Marine teleport himself to the Research Sector of Delta. McCormick also explains that when Betruger unleashed the invasion, he went to Hell with an artifact from the archaeological digs called the Soul Cube, and he believes the artifact is the only way to stop the invasion. After going through the small portal pads on Delta Labs - Level 3, the Marine reaches Delta Sector 4 and discovers the sector had been hit hardest of all. Bloody messages and corpses litter the walls and floor and finally reaches the main gateway on Delta Labs - Level 4, but Betruger activates it, sending two Hell Knights to fight him. After the Marine kills them, the gateway sends him to Hell.

In Hell he fights against many of its legions, but eventually manages to find the Soul Cube, which is protected by the Guardian of Hell. After destroying him, the Marine recovers the artifact and gets back to Mars. Shortly after his return, Betruger taunts him, saying the gateway is useless since there is another portal called Hell Gate capable of bringing millions of demons to our universe. Going through many areas of Delta Complex, the Marine finds Swann badly injured. Swann says that Sarge has turned evil and is now on Betruger’s side, and that Campbell went to hunt him down. He also reveals that the demons' plan was always to get to Earth, since they "were there before, lost in the dunes of time" and the Marine must help Campbell kill Sarge. He gives the Marine his PDA, saying that he is going to try to make it out on his own. As the Marine moves through Delta Sector 1, growth has transformed most of the facility since he first entered the facility at 2:30pm. Using the PDA, the Marine reaches the CPU Complex, only to find Campbell mortally wounded by Sarge. Before his death, Campbell warns the Marine that Sarge stole his BFG 9000. After killing Sarge, now known as Sabaoth, on the CPU Banks, the Marine goes to Site 3.

There, he finds the archeologist Pierce Rogers, who explains that the ancient Martians used both religion and science to create portals through the planets of the solar system - including Earth itself. However, these portals opened gates to Hell, which invaded the whole planet just like it did the Mars Base. The Martians, in the ultimate act of sacrifice, created the Soul Cube and energized it with their souls. Then the most powerful Martian warrior used it to drive the demons back to Hell. The few Martians left alive buried their warrior along with the Soul Cube and the stone tablets to alert anyone of the dangers of the misuse of their technology. Since Mars became a desolate planet, they fled to other planets - including Earth, which is why Rogers believes that humans are actually descendants of Martians. Pierce gives to the Marine his security clearance and locks himself up, saying that only the Soul Cube is capable of closing the Hell Gate.

As the Marine enters the original Mars Base (Caverns 1) it is already Tuesday November 16th and he reaches the Caverns at dawn. (7:38am) After restoring control to the main lift, the Marine takes it further underground to original structures of a much older facility. Fighting through demons, the Marine reaches the ancient civilization dig site of Site 2. Years of marsquakes and time is starting to bring down the structure, (not to mention some type of unidentified growth) After fighting through the ancient structure, the Marine finally reaches the Primary Dig Site (Site 3), and discovers more about the Soul Cube from a UAC info video on the tablets. The Marine also discovers a section of Hell that has crept into the Martian underground and deep within the bowels of this Hellscape. There, he encounters the invulnerable Cyberdemon, who was guarding the Hell Hole — an enormous portal to Hell. Using the Soul Cube, the Marine defeats the Cyberdemon, and the Cube itself seals the Hell Hole forever.

Afterwards, on November 20, 2145 at 9:36pm, the Recon Zulu marine team and their sentry drones arrive on Mars City to secure the base. They discover the Marine in Delta Labs as the lone survivor, since the other UAC personnel were all killed - including Councilor Swann, who died from his wounds. Recon Zulu team also stated they didn't find Dr. Betruger and didn't know his whereabouts.

The game ends in Hell, revealing that Betruger has now become the dragon-like demon known as the Maledict.

Changes from original Doom
For Doom 3 id Software employed a professional science-fiction writer named Matthew J. Costello to write the script and assist in story-boarding the entire game. id Software focused on retelling the story and creating a tense horror atmosphere instead of the brisk, action-packed atmosphere of the original games. The game's events and atmosphere show a great deal of influence from George Romero's Living Dead series and James Cameron's Aliens, as well as Valve Software's Half-Life.

Similar to the story of the original Doom, the game focuses on the marine who is transferred to Mars and sent out on a routine mission, and who needs to kill zombies and demons from Hell. One difference is that Doom 3 is set on Mars itself, whereas the first two episodes of the original Doom take place on Phobos and Deimos, respectively (Mars is always considered secured by the humans).

The environment of Doom 3 is generally much more realistic. For example, whereas the original Doom gives the two moons breathable atmospheres, Doom 3's Martian atmosphere is unbreathable (although oxygen tanks allow the player to breathe for a brief time), but the gravity is still the same as Earths, instead of being slightly lower like Mars should be. (If the player with all his gear weighed 300 pounds on Earth, he would weigh 120 pounds on Mars.)

In both cases, the protagonist visits Hell. In the original Doom, it is the third episode, Inferno (Ultimate Doom adds a fourth, Thy Flesh Consumed, which takes place on Earth), whereas in Doom 3, it is only one level (the Xbox version's Hell level is separated into three levels, to make it easier on the console), but Doom 3's Hell level is much longer and more intense than the others, and with screaming of damned souls and the steaming hot magma. It also has a boss called the Guardian. Other bosses include the Spider Queen, or Vagary (inspired by Dungeons and Dragons' Drider, a dark-elf/spider hybrid; Quake's Vore; the Black Widow in Quake 2: Ground Zero; and possibly the spiderdemon from the original Doom), tank-like cyborg called Sabaoth and the final boss, the Cyberdemon.

Unlike in previous id games, there are now cut scenes that give purpose and context for the player's actions and introduction to new enemies. Similar to other science fiction action/horror games such as ', ' and , hundreds of text, voice, and video messages are scattered throughout the base. The messages are internal e-mails and audio reports sent between doctors, scientists/lab workers, administrators, maintenance staff, and security personnel at the Mars base. The messages explain the background story, show the feelings and concern of the people on the Mars base and reveal information related to plot and gameplay. Video booths and televisions give planetary news, corporate propaganda, visitor information and technical data about the base and even weapons.

The story of Doom 3 surrounds the discovery of ancient ruins underneath Martian soil. Tablets found at these sites record how an ancient Martian race developed a form of teleporter technology. They realized an important fact all too late, as the route the teleporter took passed through Hell. Quickly invaded by demons, this alien race created and sacrificed themselves to a weapon known as the Soul Cube. This cube, powered by the souls of almost every being of this alien race, was used by their strongest warrior to defeat the demons and contain them in Hell.

Having done so, the remainder of the alien race constructed warnings to any who visited Mars, warning them not to recreate this technology; to avoid opening another gate to Hell. They then teleported to an unknown location, fleeing Mars; there are hints that at least some of them fled to Earth, and that humans descended from them. It's stated that the demons once inhabited Earth in an unknown context, but lost possession of it due to an unknown cause. Consequently, the demons want to reclaim Earth.

Gameplay
Doom 3’s gameplay was not as fast-paced as the games before it. Almost all of the game is extremely dark, and there is no Light amplification visor, nor do weapons have a flashlight attachment. Instead the player must rely on, rather infamously, a flashlight that can only be used in place of a weapon. There are few tactics involved other than grabbing the biggest weapons.

Much of the game takes place in dark close-quarters with demons ambushing from every direction. By contrast the Hell level of the game is considered by many to be the best, as it is more similar to the Doom games of the past, featuring more open areas and making use of unique effects.

Difficulty
There are four difficulty levels in Doom 3: Recruit, Marine, Veteran, and Nightmare. The first three are always available. On Recruit difficulty, there are fewer monsters, but it is a negligible amount. The principal difference between the difficulties is the amount of damage the player receives. The chart on the right indicates the amount of damage the player will receive on each difficulty level, relative to the definition files (.def).

Upon completion of a campaign regardless of difficulty level, the player unlocks the "Nightmare" difficulty setting. When playing the game on this setting, the player's health falls in 5-point increments at 5-second intervals until it reaches 25, where it remains steady. Additionally, there are absolutely no medkits throughout the game; the only means of procuring health is either by the health stations, which are still operational, or use of the Soul Cube, which is given to the player at the very start of the game.

The difficulty setting can be controlled by the controllable variable,. The damage changes take effect immediately, but a map restart or change is necessary for the rest. For example, if a player begins the level on Recruit difficulty and then enters  in the console, immediately their health will begin its drop to 25 and they will receive Nightmare damage. However, the Soul Cube is not given, medkits remain in the level, and the amount of monsters does not increase.

Weapons
Most of Doom 3's weapons are updated versions of the classic weapons, but those marked with an asterisk are new additions to the series. Several weapons are also based upon these found in Quake II.

As the game generally takes place in dark mazes, there is no long distance "sniper" weapon such as the Railgun found in Quake II and III; this omission was notable as it was a FAQ. As in previous Quake titles, Doom 3's rocket launcher allows rocket-jumping, but it is of little or no use in closed levels. Weapons require reloading, unlike the original series, requiring players to manage their inventory more efficiently before they enter themselves into another messy fight. In addition, the pistol, machine gun, and chaingun each use different calibers, therefore they do not share the same ammo pool as in earlier Doom games. This is also the case with the Plasma gun and the BFG. Also introduced are drones and sentry bots that will aid players as "gun buddies" in some areas. Certain items and contraptions (such as machinery and barrels) in the area can also be exploited, manipulated or avoided at will.


 * Fists
 * Flashlight*
 * Pistol
 * Shotgun
 * Machine gun*
 * Chaingun
 * Plasma gun
 * Rocket launcher
 * Super Shotgun
 * BFG 9000
 * Chainsaw
 * Grenades*
 * Soul Cube*

Enemies
Doom 3 includes updated versions of many monsters from the original games, and also introduces some new ones. Some of the old monsters, such as the Demon and the Hell Knight, are very different from their predecessors, whereas others, like the Revenant and Mancubus, are fairly close to the originals. Still others, such as the Imp and Lost Soul, are in between, having undergone significant changes but are still easily recognizable.

The enemies are divided into two groups: zombies and demons. Zombies were once former humans who have been possessed by hellish spirits that are now hostile to the player, while demons are the creatures from Hell. Unlike classic Doom, Doom 3's demons have their bodies dissolve when they die, except zombies and certain bosses.


 * Arch-vile
 * Cacodemon
 * Cyberdemon
 * Hell knight
 * Imp
 * Lost soul
 * Mancubus
 * Pinky
 * Revenant
 * Zombie
 * Chainsaw zombie
 * Fat zombie
 * Flaming zombie
 * Morgue zombie
 * Zombie commando
 * Zombie security guard

Additionally, the following new monsters are encountered:


 * Cherub
 * Guardian
 * Seeker
 * Maggot
 * Sabaoth
 * Tick
 * Trite
 * Vagary
 * Wraith

Several monsters were also left unfinished and were not included in the finished game.

Levels

 * 1) Mars City
 * 2) Mars City Underground: Union Aerospace Subsystems
 * 3) Mars City: Union Aerospace Corporate Division
 * 4) Administration: Union Aerospace Corporate Division
 * 5) Alpha Labs - Sector 1: Union Aerospace Science Division
 * 6) Alpha Labs - Sector 2: Union Aerospace Science Division
 * 7) Alpha Labs - Sector 3: Union Aerospace Science Division
 * 8) Alpha Labs - Sector 4: Union Aerospace Science Division
 * 9) Enpro Plant: Energy Processing and Storage
 * 10) Communications Transfer: Maintenance and Transfer Station
 * 11) Communications: Central Communications Tower
 * 12) Monorail Skybridge: Facility Transport
 * 13) Recycling - Sector 2: Waste Recycling Center
 * 14) Monorail: Facility Transport
 * 15) Delta Labs - Level 1: Union Aerospace Research Division
 * 16) Delta Labs - Level 2a: Union Aerospace Research Division
 * 17) Delta Labs - Level 2b: Union Aerospace Research Division
 * 18) Delta Labs - Level 3: Union Aerospace Research Division
 * 19) Delta Labs - Level 4: Union Aerospace Research Division
 * 20) Hell
 * 21) Delta Complex: Union Aerospace Research Division
 * 22) Central Processing: Processing Distribution Center
 * 23) Central Processing: Primary Server Bank
 * 24) Site 3: Analysis Facility
 * 25) Caverns - Area 1: Excavation Transfer
 * 26) Caverns - Area 2: Artifact Excavation
 * 27) Primary Excavation: Artifact Dig

Xbox port
The Xbox version was sold in both a standard case, as well as a special edition sold in a metal case. The metal case edition had several extras—interviews, G4’s Icons Doom episode, early artwork, and the full versions of Ultimate Doom and Doom II. The Xbox Collectors edition includes two more levels, one in Ultimate Doom (E1M10: Sewers) and one in Doom II (MAP33: Betray).

The Xbox port's textures are less detailed than that of the PC version and splits many levels up into separate parts due to console limitations. Even though the levels are split up, some levels have been rearranged and some areas have been simplified presumably because the Xbox hardware would suffer otherwise. Nonetheless, most reviewers were impressed that the Xbox had otherwise retained all of the other features, considering that its NV2A graphics processor (equivalent to an Nvidia GeForce 3, the original base card for Doom 3) was a generation behind the recommended video cards (ATI Radeon 9700 and GeForce 4 Ti) for the PC version. The NV2A processor was what distinguished the Xbox from the PlayStation 2 and GameCube, the latter two consoles were not considered for a Doom 3 port due to insufficient hardware. The PC version had been originally designed with the GeForce 3 in mind but now that GPU is barely sufficient to run the game; a Radeon 9700 was used to run the E3 2002 demo.

The Xbox version has added co-op play, which required the modification of levels, such as widening corridors to comfortably accommodate a second player.

This version is compatible with Xbox 360.

Xbox controls

 * Left Thumbstick: Move
 * Right Thumbstick: Look
 * Click & Hold Left Thumbstick: Crouch
 * Click & Hold Right Thumbstick: Zoom
 * A: Jump
 * B: Previous Weapon
 * X: Reload
 * Y: Next Weapon
 * Left Trigger: Sprint
 * Right Trigger: Action
 * White (LB for 360): Equip/Unequip Flashlight
 * Black (RB for 360): PDA/Multiplayer Score
 * Start: Pause
 * Back: Save/Ready

The D-Pad arrows serve as hotkeys to select weapons instead of cycling through every weapon in inventory. Four weapons can be assigned. The weapon assigned to each arrow is customizable.

Doom 3 BFG Edition

 * Main article: Doom 3 BFG Edition

Doom 3 BFG Edition is a remastered edition of Doom 3 for the PC, Xbox 360, and the PlayStation 3. The game was released on October 16, 2012.

Reception
Few games have polarized gaming as much as Doom 3 has, and many reactions to the game are in heavy contrast to one another.

Criticism
Some commonly named shortcomings of the game are:


 * Reliance on traditionally overused horror techniques such as pitch black darkness, limited use of the flashlight and stock horror movie clichés, which may make the game frustrating to play rather than scary or atmospheric.
 * Movement is more realistic, hence slower than Doom, Doom 2 and the Quake series.
 * No ability to use the flashlight and the weapon at the same time, known as "No duct tape on Mars" problem, whereas today many real-life weapons have hands-free light attachments (as a result of this, many light-mods on the internet add a flashlight to the guns).
 * Somewhat stale storytelling techniques, forcing the player to read or listen to messages by hiding access codes in them, and a shortage of cut-scenes providing story exposition, with one reviewer saying that adding clumsy storytelling to the game ending up weakening the experience.
 * Over-reliance on scripted sequences. Reviewers particularly criticized the monster ambushes that are triggered by the player, while some do fit in with the premises of the level (demonic enemies can be reasoned to come from flaming vats), other enemy spawn points are simply at where powerups are.
 * Somewhat limited use of physics, which was improved significantly in the Resurrection of Evil expansion.
 * A small multiplayer deathmatch mode of only a few people, stemming from Doom 3's focus on the single player experience.
 * No official cooperative gameplay in the PC version whereas the original Doom contained a cooperative mode. Co-op mode was included in the Xbox port of Doom 3, which required the redesign of maps to accommodate two players.

Some critical reviewers consider that the technological level of Doom 3 is similar to that of other games of 2004, and that features such as bump mapping had already become industry standard. For example, an often mentioned feature of Doom 3, per-pixel lighting and stencil shadowing, had already been implemented in some games released in 2003, even a budget title from Activision Value called Secret Service: Security Breach.

The BFG edition includes some improvements based on feedback, most notably the ability to use a flashlight and a weapon at the same time.

Rebuttals to criticism
Many gamers argue the apparent shortcomings are not shortcomings at all, but are integral to the gameplay id determined to display for Doom 3.

Since Doom 3 is a remake of the original Doom - a game which did not have high-end concepts common in today's more complex games - remaking Doom with too much complexity would remove a key component that made Doom popular in the first place.

The deliberate slow pace, horror clichés, and overly scripted sequences (including the randomness of enemy spawning points) is designed to inspire terror. Every aspect of the game, from the lighting and sound to interactions and monster ambushes contribute to an overall feeling of fear and anxiety. 

The flashlight is a key element of Doom 3's gameplay: the player must balance between seeing the enemy, and defeating it. Almost every monster has glowing eyes, or some aspect of bio-luminescence which offers a target for the player. If weapons had a light attachment, this results in the mystery of "the unknown" to be less potent and frightening. Making things easier is the default flashlight toggle "F", which enables the player to switch very quickly between his weapon and the flashlight, if he is using the WASD keys and the mouse to move, similar to the rationale behind the use of the very frequently used "R" (reload weapon) key and the "C" (crouch) key. Additionally, muzzle flashes can be enabled for marginally better visibility while firing.

Another rebuttal concerns the story of Doom 3, which is done through the use of audio and video logs. The use of logs in this way is similar to the use of logs in System Shock 2. Players are free to not listen to the audio logs if they don't care about the story and just want to play the game.

A few of these criticisms of Doom 3 are based on expectations for other types of FPS games. During development, it was often compared with the equally anticipated Half-Life 2. Some have argued that since Doom 3 was released before Half-Life 2, many have come to expect things from it that they previously had expected from Half-Life 2. For example, the common complaint about Doom 3's lack of environment interactivity could be considered a subtle complaint that Doom 3 doesn't have a Half-Life 2-style "Gravity Gun", a weapon which can be used to throw or push many objects in the world, including small objects, cars, and organic lifeforms. Ironically, Doom 3 was said to have a "Gravity Gun" item designed long before Half-Life 2, but was not in the game proper. This weapon appears in the Doom 3 expansion known as Doom 3: Resurrection of Evil, which has drawn the ire of those who feel id is pandering to Half-Life 2 fans.

With regards to a minimal multiplayer mode, the designers intended that Doom 3 would be played and remembered primarily for its single-player story experience, as opposed to id Software's previous titles which were known far better for multiplayer deathmatch. (The follow-up Quake 4 would have a return to multiplayer focus using Doom 3's engine.) The Xbox port of Doom 3 did implement co-op mode but in order to make the co-op mode feasible and balance out gameplay, levels had to be redesigned to accommodate both players.

Sales
The game was a commercial success for id Software, with the planned total revenue estimated by Activision at $20 million. It was one of the top selling games of 2004, alongside Halo 2 for the Xbox and Half-Life 2. The financial success was bolstered by the near-record number of pre-orders placed for the game.

id Software also typically benefits from licensing the engine to other developers. Several games have already been developed using a modified Doom 3 engine, including Quake 4, Prey, Enemy Territory: Quake Wars, Wolfenstein and Brink

As of August 23, 2006 Doom 3 has garnered an average review score of 87%, according to 97 media outlets on GameRankings.com. By the same source, it is in the top 10 PC games of 2004.

E3 2002 Game Critics Awards: Best of Show, Best PC Game, Best Action Game, Special Commendation for Sound, Special Commendation for Graphics.

Doom 3 Timeline Events
Monday November 15th, 2145

6:18am - DarkStar arrives in Mars City Hangar

6:55am - Darkstar leaves for Burns Flat, Oklahoma, Earth (Mars-Earth trip takes 1 month)

8:00am - Energy Team Meeting in Delta Sector 1

8:30am - Atmosphere Monitoring Equipment Transfer (Communications Facility)

12:00pm - Sector 2 Preliminary and Decoherence Test (Delta 1)

1:00pm - Check all files for build (Delta 1)

1:20pm - Campbell initiates security lock down in Communications Transfer

2:30pm - Marine arrives at Delta Sector 1, Executive Personnel Tour (Delta 1)

3:30pm - Storage Crates Transfer (Communications Facility)

5:30pm - Shift 2 Energy and Administration Meetings (Delta 1)

9:00pm - Off Duty Employees Only: Jim's Birthday Party in Delta Access Lobby (Delta 1)

Tuesday November 16th, 2145

6:30am - Large Artifact Removal (Completed at 7:38am) Marine arrives at Caverns via lift from Site 3 Analysis Facility

8:00am - Final Artifact Removal (Caverns 1)

12:00pm - Construction Cotainer Transfer (Caverns 1)

6:30pm - Portable Equipment Removal (Caverns 1)

Saturday November 20th, 2145

9:36pm - Marine extracted from UAC base

May 1st 2146 - Orbital Probe records faint broadcast from the abandoned Site 1 Complex

August 8th 2146 - UAC Board of Directors renew Mars program

March 17th 2147 - Marine and his team are sent by Dr. Viktor Kharkov to investigate a hidden tunnel below the surface.

Mods

 * The Classic Doom for Doom 3 mod replays Knee-Deep in the Dead but with the new Doom 3 engine.
 * The Last Man Standing mod enables cooperative play, and introduces a new game type.
 * The Dark Mod a total conversion mod which converts Doom 3 into a game like Thief 1/2
 * Hexen: Edge of Chaos a total conversion mod which converts Doom 3 into a game like Hexen
 * Sikkmod a game-play and graphical enhancement mod that includes SSAO, DOF, and HDR
 * Bubba Lego-Tep starring Lego Elvis total conversion based on the film Bubba Ho-Tep starring Bruce Campbell

Other mods for Doom 3 include:
 * A mod that puts lights on the weapons (but which are less effective than the flashlight), colloquially known as the duct tape mod.
 * A mod that prevents the bodies of the monsters you killed from disappearing
 * A mod that makes the Cyberdemon at the end of the game vulnerable to weapons other than the Soul Cube
 * A mod featuring the Doom 3 weapons for Classic Doom source port ZDoom also exists. It includes several Doom 3 weapons (using sprite-based graphics and Decorate to recreate the weapon behavior) except for the grenades and Soul Cube. The mod works with both Doom and Doom II, though the mod lacks the super shotgun when played with Doom II.

Trivia

 * At the very beginning of the game, there are 2 posters for UAC. One of them ironically says "One step closer to heaven".
 * The Doom community long predicted a sequel to Doom II, usually referring to it as Doom 2000. Some speculation is recorded in this Doomworld mailbag from 1998-08-18.
 * TimeSplitters: Future Perfect parodied the Doom 3 audio logs in the level What Lies Below. In this level, Cortez can access a scientists’ personal audio log, which contains his locker code (or, at the very least, several three-digit numbers which he believes are his locker combination). In addition, a small segment of the level's theme song can be heard in the background in the Doom 3 level Mars City.
 * The character of Dr. Reinhard in Evil Dead: Regeneration may be a parody of Dr. Betruger. Both share a similar physical appearance, including a severe cataract in one eye. Both men also started out good but turned evil when tempted by the forces of Hell.
 * The UAC is apparently the successor organization to NASA; in one of the videos, the UAC claims to have been the leader in space technology "since the dawn of the Space Age".
 * The airlocks display pressure in pounds per square inch, showing that UAC engineers still use US-Imperial units in the 22nd century. The pressure inside the complex is 14.7 psi as on Earth's surface, while the pressure of the Martian air is given as 0.13 psi, which is more or less the true real value. (The most likely metric equivalent used in that situation would have been the kilopascal or millibar.) On the EnPro Plant level, by contrast, the temperature of the reactor core is announced in degrees Celsius, although the Celsius scale is already used for most purposes in the United States that involve temperatures far above or below room temperature.
 * After returning to Mars from Hell, a terminal in the CPU Transfer Bay Entrance displays a red screen. An email can be downloaded from this terminal, containing a rather tongue-in-cheek message written by the Hell demons on proper human sacrifice techniques.
 * In the final room before the Cyberdemon encounter, a small Id Software logo can be found on one of the bricks in a corner. Approaching this turns the crosshair into a mouse arrow as would happen if the player approached a terminal. Clicking this opens a secret room which contains a PDA. Picking this PDA up downloads special "thank you" messages from the id Software staff.
 * The large Hell Gate that is present on the menu selection screen resembles the Stargate from the movie/television Stargate franchise, with the constellation markings replaced by runes.
 * The name 'Dr. Betruger' has a strong similarity to the German word 'Betrüger' which means 'deceiver' or 'impostor'.
 * If the player earns a score of 25,000 on the in-game arcade game Super Turbo Turkey Puncher 3, an e-mail will be sent to the PDA congratulating on setting a new high score, being a shining example of humanity by punching defenseless turkeys, and losing two days of leave.
 * After receiving the PDA, the receptionist returns to typing on his screen. He types an e-mail message about the player arriving to Mars and being very rude for reading over his shoulder.
 * http://www.martianbuddy.com is an actual website that provides the code to the two Martian Buddy lockers within the game.
 * Trying to access this website will redirect to Bethesda's main site.
 * After receiving the pistol, you can kill the civilian working on the crane and take his PDA.
 * In the Primary Excavation: Artifact Dig level, in the room with several tablets, one can be compared to the original Doom cover but with fewer demons and the Doomguy has the soul cube in his hands. It also has his head broken off.
 * The weapons in the Hell level of Doom 3 feature only weapons that appeared in all of the Doom games (Fists, Pistol, Shotgun, Chaingun, Plasma Gun, Chainsaw, Rocket Launcher and BFG9000).
 * During the very first levels, you can see some UAC workers located in places you cannot normally reach. After activating the noclip cheat code and getting to these areas, you can see that all of the "unreachable persons" share the name Joe.
 * Doom 3's working title was "Neo",
 * In the Alpha release of Doom, the death sound of the Hell Knight in Doom 2 is reused for the leaping attack sound of the alpha Imp.
 * Later in the game of Doom 3's Expansion Resurrection of Evil, the player teleports to parts of the UAC Base and it appears that the growth that had "infected" parts of the base had gotten worse over the course of time (6 months - 3 years) it was left abandoned.
 * Doom 3 is notably inspired by the 1998 game Half-Life this is seen apparent in the focusing of teleporters in the games, an elite military presence in both (HECU/Black Ops in Half-Life and Marines in Doom 3), the use of a monorail system, and the scientists prior knowledge and research of the major non-human faction (Xen in Half-Life's case, and Hell in Doom's case).

References to Classic Doom
See main article: References to Classic Doom in Doom 3.

Expansion
See Doom 3: Resurrection of Evil.