wiki143 - User contributions [en]

Id Tech 4

2025-06-30T10:13:22Z

143.159.76.2:

{{Short description|Video game engine}}
{{Use mdy dates|date=August 2015}}
{{Lowercase title}}
{{Infobox video game engine
| name = id Tech 4
| logo =
| screenshot = Reverent (Doom).jpg
| caption = ''[[Doom 3]]'', the id Tech 4 engine's parent game
| collapsible =
| developer = [[id Software]]
| replaces = [[id Tech 3]]
| replaced_by = [[id Tech 5]]
| latest release version =
| latest release date =
| repo = [https://github.com/id-Software/DOOM-3-BFG github.com/id-Software/DOOM-3-BFG]
| tools =
| programming language = [[C++]]<ref>{{cite web|url=https://github.com/id-Software/DOOM-3-BFG|title=id Tech 4 Source Code|website=[[GitHub]] |date=March 30, 2020|access-date=September 11, 2015|archive-date=April 18, 2019|archive-url=https://web.archive.org/web/20190418120317/https://github.com/id-Software/DOOM-3-BFG|url-status=live}}</ref>
| platform = [[Microsoft Windows]], [[OS X]], [[Linux]], [[PlayStation 3]], [[PlayStation 4]], [[Xbox (console)|Xbox]], [[Xbox 360]], [[Xbox One]], [[Nintendo Switch]], [[Nintendo Switch 2]], [[Nvidia Shield (set-top box)|Nvidia Shield]]<ref>{{cite web |url=http://www.mobygames.com/game-group/3d-engine-id-tech-4 |title=3D Engine: id Tech 4 |access-date=September 24, 2008 |archive-date=January 28, 2012 |archive-url=https://web.archive.org/web/20120128053734/http://www.mobygames.com/game-group/3d-engine-id-tech-4 |url-status=live }}</ref>
| license = [[GNU General Public License|GNU GPL-3.0-or-later]]
}}

'''id Tech 4''', popularly known as the '''''Doom 3'' engine''', is a [[game engine]] developed by [[id Software]] and first used in the [[video game]] ''[[Doom 3]]''. The engine was designed by [[John D. Carmack|John Carmack]], who also created previous game engines, such as those for ''[[Doom engine|Doom]]'' and ''[[Quake engine|Quake]]'', which are widely recognized as significant advances in the field. This [[OpenGL]]-based game engine has also been used in ''[[Quake 4]]'', ''[[Prey (2006 video game)|Prey]]'', ''[[Enemy Territory: Quake Wars]]'', ''[[Wolfenstein (2009 video game)|Wolfenstein]]'', and ''[[Brink (video game)|Brink]]''. id Tech 4 is licensed under the terms of the [[GNU General Public License|GNU General Public License v3.0 or later]], and is to date the last id Tech engine to be open-sourced.

== History ==
id Tech 4 began as an enhancement to [[id Tech 3]]. During development, it was initially just a complete rewrite of the engine's [[Rendering (computer graphics)|renderer]], while still retaining other subsystems, such as file access, and memory management. The decision to switch from [[C (programming language)|C]] to the [[C++]] [[programming language]] necessitated a restructuring and rewrite of the rest of the engine; today, while id Tech 4 contains code from id Tech 3, much of it has been rewritten.<ref>{{cite web|url=http://archive.gamespy.com/e32002/pc/carmack/|title=Q&A with John Carmack, E3 2002|archive-url=https://web.archive.org/web/20090929091428/http://archive.gamespy.com/e32002/pc/carmack/|archive-date=September 29, 2009}}</ref>

At the [[QuakeCon]] 2007, [[John D. Carmack|John Carmack]], the lead graphics engine developer at id, said to [[LinuxGames]]:
"I mean, I won't commit to a date, but the Doom 3 stuff will be open source". And like its predecessors, John Carmack has said that id Tech 4 will be released as [[open-source software|open-source]].<ref>{{cite web |last=Carmack |first=John |url=http://www.linuxgames.com/archives/9374 |title=I mean I won't commit to a date, but theDoom 3 stuff will be open source |publisher=LinuxGames.com |date=August 7, 2007 |url-status=dead |archive-url=https://web.archive.org/web/20081003111457/http://www.linuxgames.com/archives/9374 |archive-date=October 3, 2008 |df=mdy-all }}</ref>

At the QuakeCon 2009, Carmack said that he planned to petition [[ZeniMax Media]] to release the id Tech 4 source upon the release of ''[[Rage (video game)|Rage]]''.<ref>{{cite web|url=http://kotaku.com/5336589/the-john-carmack-keynote-liveblogging-quakecon|title=The John Carmack Keynote: Liveblogging QuakeCon|date=August 13, 2009 |access-date=August 14, 2009|archive-date=August 14, 2009|archive-url=https://web.archive.org/web/20090814235911/http://kotaku.com/5336589/the-john-carmack-keynote-liveblogging-quakecon|url-status=live}}</ref> As part of his keynote for QuakeCon 2011, he confirmed that the source code to ''Doom 3'' would be out by the end of the year, after the release of ''Rage''.<ref name=2099819-doom3>{{cite web |url=http://www.theinquirer.net/inquirer/numb-thumbs-blog/2099819/id-software-release-doom-source-code |archive-url=https://web.archive.org/web/20110807171418/http://www.theinquirer.net/inquirer/numb-thumbs-blog/2099819/id-software-release-doom-source-code |url-status=unfit |archive-date=August 7, 2011 |title=Id Software will release the Doom 3 source code |publisher=The Inquirer |date=August 5, 2011 |access-date=August 23, 2015}}</ref>

On November 16, 2011, Carmack announced on [[Twitter]] that he's writing new code for Doom 3's open source release, because "lawyers are still skittish about the patent issue around 'Carmack's reverse'".<ref>{{cite web|url=https://twitter.com/ID_AA_Carmack/statuses/136614459887202305|title=John Carmack's Twitter status update|date=November 16, 2011|access-date=November 18, 2011|archive-date=August 26, 2021|archive-url=https://web.archive.org/web/20210826111524/https://twitter.com/ID_AA_Carmack/statuses/136614459887202305|url-status=live}}</ref> This refers to an implementation of [[stencil buffer]]ed [[shadow volume]] algorithms.

On November 22, 2011, Carmack released the ''Doom 3'' source code under [[GNU General Public License|GNU GPL-3.0-or-later]] on [[GitHub]].<ref>{{cite web|url=https://github.com/TTimo/doom3.gpl|title=Doom 3 Source on GitHub|website=[[GitHub]] |date=November 22, 2011|access-date=November 22, 2011|archive-date=July 21, 2013|archive-url=https://web.archive.org/web/20130721074246/https://github.com/TTimo/doom3.gpl|url-status=live}}</ref> The source does not include any of the 'Carmack's Reverse' code. According to Carmack, minor tweaks were made to the code to avoid any infringement.<ref>{{cite web|url=https://twitter.com/ID_AA_Carmack/status/137189212519792640|title=John Carmack tweets about code infringement work around|date=November 17, 2011|access-date=November 22, 2011|archive-date=May 16, 2017|archive-url=https://web.archive.org/web/20170516023251/https://twitter.com/ID_AA_Carmack/status/137189212519792640|url-status=live}}</ref> Since then, several open-source projects have been released, such as dhewm3, Dante, and RBDOOM-3-BFG.<ref>{{cite web |last1=Larabel |first1=Michael |title=One Year Later, Open-Source Doom 3 Is Moving Slowly |url=https://www.phoronix.com/news/MTIzMjU |website=[[Phoronix]] |access-date=29 April 2024 |date=20 November 2012}}</ref><ref>{{cite web |last1=Larabel |first1=Michael |title=Open-Source Doom 3 BFG Ported To Linux |url=https://www.phoronix.com/news/MTI1NzE |website=[[Phoronix]] |access-date=29 April 2024 |date=19 December 2012}}</ref><ref>{{cite web|url=https://www.dsogaming.com/news/final-version-of-doom-3-source-port-dhewm3-available-for-download-supports-4k-openal-and-more/|title=Final version of Doom 3 source port, dhewm3, available for download, supports 4K, OpenAL and more|date=2018-12-17|access-date=2024-07-14|first=John|last=Papadopoulos|website=DSO Gaming}}</ref> In 2021 the ''[[Quake 4]]'' game DLLs were adapted for use with the [[open source]] dhewm3 engine [[Source port|derived from]] the released ''[[Doom 3]]'' source code (with work also started on ''[[Prey (2006 video game)|Prey]]''); this has since been used to port the game to [[AmigaOS 4]].<ref>{{cite web|url=https://www.generationamiga.com/2023/01/02/hunnoppc-working-on-quake-4-port-for-amigaos-4-1/|title=HunnoPPC Working on Quake 4 port for AmigaOS 4.1|website=Generation Amiga|date=2023-01-02|access-date=2023-03-24}}</ref>

=== Hardware ===
The original requirement of id Tech 4 was that it needed a high-end graphics processing unit (GPU) with fully programmable vertex and pixel shaders, such as the [[Nvidia]] [[GeForce 3]] or [[ATI Technologies|ATI]] [[Radeon 8500]], with at least 64 MB of VRAM. By [[E3]] 2002, the recommended GPU was "100% [[DirectX]] 9.0b compatible", such as the [[Radeon 9700]] with 128 MB of VRAM. While the Radeon 9700's 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.<ref>{{cite web|title=ATI's Radeon 9700 Takes Performance Lead|url=http://www.neowin.net/news/main/02/07/20/atis-radeon-9700-takes-performance-lead|archive-url=https://wayback.archive-it.org/all/20090921001415/http://www.neowin.net/news/main/02/07/20/atis-radeon-9700-takes-performance-lead|url-status=dead|archive-date=September 21, 2009|access-date=September 25, 2012|df=mdy-all}}</ref> The "Ultra" graphics mode included in ''Doom 3'' would not even run on high end graphics cards in 2004, as the engine required at least 512 MB of video memory to display properly and at playable speeds.<ref>{{cite web|url=http://www.gameindustry.com/review/item.asp?id=449|title=Doom is a boon|publisher=Game Industry News|last=Hargosh|first=Todd|access-date=June 11, 2011|url-status=dead|archive-url=https://web.archive.org/web/20110727033856/http://www.gameindustry.com/review/item.asp?id=449|archive-date=July 27, 2011|df=mdy-all}}</ref>

id Tech 4 resulted in the obsolescence of DirectX 7 graphics chips such as the widespread [[GeForce 2]] and [[Radeon R100|Radeon 7200]], as well as older chipsets such as [[RIVA TNT2]] and [[Rage 128]], and software rendering (with an integrated [[Intel GMA]]). Until the advent of id Tech 4, a powerful CPU was able to somewhat compensate for an older video card. While [[John D. Carmack|John Carmack]] initially warned gamers not to purchase the [[GeForce 4]] MX<ref>{{cite web|url=http://www.bluesnews.com/cgi-bin/finger.pl?id=1&time=20020211165445|title=.plan File for John Carmack - Blue's News|work=Blue's News|access-date=May 25, 2016|archive-date=March 3, 2016|archive-url=https://web.archive.org/web/20160303222118/http://www.bluesnews.com/cgi-bin/finger.pl?id=1&time=20020211165445|url-status=live}}</ref> (which casual consumers often confused with the DirectX 8 capable GeForce 4 Ti, though it was at best an improved [[GeForce 2]]){{Citation needed|reason=vague "casual consumers"; which card, and who makes the judgement that "it" was "at best" anything? |date=August 2016}}, its somewhat widespread adoption compelled id Software to add it to the list of supported cards. There have been cases of enthusiasts forcing ''[[Doom 3]]'' to run on unsupported graphics chips, such as the long obsolete [[Voodoo 2]], but these are unable to render the per-pixel lighting and bump mapping.<ref>{{cite web|title=Doom3 + Voodoo2_Patch_v1_0|url=http://www.3dfxzone.it/enboard/topic.asp?TOPIC_ID=1462|access-date=September 25, 2012|archive-date=December 5, 2008|archive-url=https://web.archive.org/web/20081205054717/http://www.3dfxzone.it/enboard/topic.asp?TOPIC_ID=1462|url-status=live}}</ref>

== Features ==
[[Image:Doom3shadows2.jpg|thumb|200px|The shadowing effects of the unified lighting and shadowing engine are shown on the face and body of the zombies in this screenshot from ''Doom 3''. Normal maps add additional shadow details without requiring additional model detail.]]

=== Graphics ===
Id Tech 4 added several new graphical features absent in its predecessor, [[id Tech 3]]. These included [[normal mapping]] and [[specular highlight]]ing. More features were added in the development of successive games.

The models used in id Tech 4 games are animated using [[skeletal animation]]. The engine can blend multiple animations together to produce a skin that moves correctly for those animations. Because this is CPU intensive, id did some work optimizing this by using [[Intel]]'s [[Streaming SIMD Extensions]] (SSE).<ref>{{cite web|url=http://software.intel.com/en-us/articles/optimizing-the-rendering-pipeline-of-animated-models-using-the-intel-streaming-simd-extensions/|title=Optimizing the Rendering Pipeline of Animated Models Using the Intel Streaming SIMD Extensions|work=intel.com|access-date=May 25, 2016|archive-date=June 24, 2016|archive-url=https://web.archive.org/web/20160624041143/https://software.intel.com/en-us/articles/optimizing-the-rendering-pipeline-of-animated-models-using-the-intel-streaming-simd-extensions/|url-status=live}}</ref>

====Dynamic lighting====
[[File:Radiosity_Comparison.jpg|thumb|300px|This image shows two renders of the same space with and without [[radiosity (computer graphics)|radiosity]]. The dynamic lighting system in ''Doom 3'' does not simulate radiosity, in contrast with the baked lightmaps of prior id Tech engines.]]

The primary innovation of id Tech 4 was its use of entirely dynamic [[per-pixel lighting]] and [[shadow volume]]s, whereas previously, 3D engines had relied primarily on pre-calculated per-vertex lighting or [[lightmap]]s and [[Gouraud shading]], and shadows were either faked (such as the traveling dark spot beneath characters in id Tech 3 games) or non-existent. id Tech 4 unified lighting and shadows,<ref>{{cite web|url=https://www.tweaktown.com/articles/9387/doom-eternal-benchmarked-at-8k-not-even-the-devil-can-run-this/index.html|title=DOOM Eternal Benchmarked at 8K - Not Even The Devil Can Run This|website=Tweatwon|date=March 30, 2020 |access-date=2023-11-06}}</ref> something absent in prior id Tech engines. All light sources in ''Doom 3'' are dynamic, something the companion book ''The Making of Doom 3'' describes as "The biggest headache for the level designers".<ref>Kent, Steven L. ''The Making of Doom ''. McGraw-Hill, 2004., pp. 116.</ref> While dynamic effects had been available before (such as dynamic moving lights), this effect merely changed the brightness of the vertices of the polygon, with the pixel's colors simply being interpolated between the three vertex colors of its polygon.

This fully realtime approach used in ''Doom 3'', combined with the use of shadow volumes permitted more realistic lighting and shadows<ref>{{cite web|url=https://www.pricenfees.com/digit-life-archives/doom-3|title=Doom 3|date=March 2, 2005|publisher=Pricenfees|access-date=May 25, 2016|archive-date=August 13, 2018|archive-url=https://web.archive.org/web/20180813181410/https://extensivelyreviewed.com/doom-3.html|url-status=live}}</ref> than in the previous generation of id's engines. The method used to create the shadow volumes is the subject of a patent by [[Creative Technology|Creative]], which Creative granted id permission to use in the ''Doom 3'' engine, in exchange for supporting Creative's [[Environmental Audio Extensions|EAX]] advanced sound technologies.<ref>{{cite web|url=https://arstechnica.com/old/content/2004/07/4048.ars|title=John Carmack: "This sucks."|work=Ars Technica|date=July 28, 2004|access-date=May 25, 2016|archive-date=January 26, 2012|archive-url=https://web.archive.org/web/20120126193051/http://arstechnica.com/old/content/2004/07/4048.ars|url-status=live}}</ref>

==== MegaTexture rendering technology ====

The original version of the id Tech 4 engine was designed for somewhat dark environments and was criticized for its perceived inability to handle extremely large daytime outdoor areas. The MegaTexture technology (a form of [[clipmap]]ping) tackled this issue. By painting a single massive texture (initially 32,768×32,768 [[pixel]]s, later extended to larger dimensions in subsequent versions) covering the entire polygon map and highly detailed terrain, the desired effects can be achieved. The MegaTexture can also store physical information about the terrain such as the amount of traction in certain areas or indicate what sound effect should be played when walking over specific parts of the map. i.e. walking on rock will sound different from walking on grass.<ref>{{cite web|url=http://pc.gamespy.com/pc/enemy-territory-quake-wars/681231p1.html|title=GameSpy: Enemy Territory: Quake Wars - Page 1|work=gamespy.com|access-date=May 25, 2016|archive-date=August 13, 2018|archive-url=https://web.archive.org/web/20180813181747/http://pc.gamespy.com/pc/enemy-territory-quake-wars/681231p1.html|url-status=live}}</ref> The first game utilizing MegaTexture is ''[[Enemy Territory: Quake Wars]]'', based on the Tech 4 engine. All [[id Tech 5]] and [[id Tech 6]] games use MegaTexture, with the exception of ''[[The Evil Within]]'', which uses a new renderer.<ref>{{cite web|url=https://twitter.com/ID_AA_Carmack/status/518052351501164544|title=John Carmack on Twitter|work=Twitter|access-date=May 25, 2016|archive-date=November 14, 2019|archive-url=https://web.archive.org/web/20191114121439/https://twitter.com/ID_AA_Carmack/status/518052351501164544|url-status=live}}</ref><ref>{{cite web|url=https://twitter.com/ID_AA_Carmack/status/522513462706982912|title=John Carmack on Twitter|work=Twitter|access-date=May 25, 2016|archive-date=January 19, 2015|archive-url=https://web.archive.org/web/20150119224143/https://twitter.com/ID_AA_Carmack/status/522513462706982912|url-status=live}}</ref> ''[[Brink (video game)|Brink]]'', which uses a heavily modified version of id Tech 4, also uses virtual texturing.<ref>{{Cite web|url = http://www.pcgameshardware.com/aid,691212/Brink-Multi-core-support-and-better-scaling-on-the-PC/News/|title = BRINK: Multi-core support and better scaling on the PC|date = July 29, 2009|access-date = May 25, 2016|archive-date = September 13, 2011|archive-url = https://web.archive.org/web/20110913082407/http://www.pcgameshardware.com/aid,691212/Brink-Multi-core-support-and-better-scaling-on-the-PC/News/|url-status = live}}</ref><ref>{{Cite web |url=http://www.splashdamage.com/downloads/pubs/brink_preferred_rendering_with_opengl.pdf |title=Archived copy |access-date=May 25, 2016 |archive-date=August 9, 2014 |archive-url=https://web.archive.org/web/20140809082337/http://www.splashdamage.com/downloads/pubs/brink_preferred_rendering_with_opengl.pdf |url-status=dead }}</ref> While the implementation is different from MegaTexture, it was inspired by it.<ref>{{cite web|url=http://silverspaceship.com/src/svt/|title=Sparse Virtual Textures|work=silverspaceship.com|access-date=May 25, 2016|archive-date=March 23, 2012|archive-url=https://web.archive.org/web/20120323170402/http://silverspaceship.com/src/svt/|url-status=live}}</ref><ref>{{cite web|url=http://charles.hollemeersch.net/node/58|title=Brink technical analysis|work=hollemeersch.net|access-date=May 25, 2016|url-status=dead|archive-url=https://web.archive.org/web/20160327220006/http://charles.hollemeersch.net/node/58|archive-date=March 27, 2016|df=mdy-all}}</ref>

===Scripting===
id Tech 4 has a comprehensive [[scripting language]] that can be used when creating [[Mod (computer gaming)|mods]], and is used in ''Doom 3'' to control monsters, weapons, and map events. This scripting language is similar to C++.<ref>{{cite web|url=http://www.iddevnet.com/doom3/script.php|title=id.sdk [Scripts]|work=iddevnet.com|access-date=May 25, 2016|archive-url=https://web.archive.org/web/20151210194609/https://www.iddevnet.com/doom3/script.php|archive-date=December 10, 2015|url-status=dead}}</ref>

In addition to the main scripting language, idTech 4 also has another scripting language that is used for [[Graphical user interface|GUIs]]—both the menus and [[HUD (video gaming)|HUD]], and also for GUIs embedded into the game world.<ref>{{cite web|url=http://www.iddevnet.com/doom3/guis.php|title=id.sdk [GUIs]|work=iddevnet.com|access-date=May 25, 2016|archive-url=https://web.archive.org/web/20160811224944/https://www.iddevnet.com/doom3/guis.php|archive-date=August 11, 2016|url-status=dead}}</ref> These in-game GUIs are sufficiently powerful that you can, for example, run another game such as the original ''[[Doom (1993 video game)|Doom]]'' within the game-world.<ref>{{cite web|url=http://www.battleteam.net/tech/fis/|title=Fully Interactive Surfaces|work=battleteam.net|access-date=May 25, 2016|archive-date=April 9, 2016|archive-url=https://web.archive.org/web/20160409045053/http://www.battleteam.net/tech/fis/|url-status=live}}</ref>

Despite this additional level of scripting, it is also possible to create [[Mod (computer gaming)|mods]] using C++ to build native code.<ref name="id.sdk The Code">{{cite web|url=http://www.iddevnet.com/doom3/code.php|title=id.sdk [The Code]|work=iddevnet.com|access-date=May 25, 2016|archive-url=https://web.archive.org/web/20160307063734/https://www.iddevnet.com/doom3/code.php|archive-date=March 7, 2016|url-status=dead}}</ref>

===Sound===
As a result of the agreement with Creative regarding the patent on shadow volumes, the id Tech 4 engine supports [[OpenAL]], including the [[Creative Technology]] specific [[Environmental audio extensions|EAX]] extensions. The work to include OpenAL support was done by Creative Technology, not by id themselves.<ref>{{cite web|title=How the latest Sound Blaster X-Fi technology was utilized in QUAKE 4|url=http://www.creative.com/soundblaster/products/gaming/article.asp?articleID=59801&categoryID=13|access-date=September 25, 2012|url-status=dead|archive-url=https://web.archive.org/web/20120804211416/http://www.creative.com/soundblaster/products/gaming/article.asp?articleID=59801&categoryID=13|archive-date=August 4, 2012|df=mdy-all}}</ref>

===Networking===
The engine uses a traditional [[client–server model]]. Initially it was planned to have a [[peer-to-peer]] networking model.<ref>{{cite web|url=http://uk.pc.gamespy.com/articles/531/531027p1.html|title=Doom 3 multiplayer networking info|url-status=dead|archive-url=https://web.archive.org/web/20110831200833/http://uk.pc.gamespy.com/articles/531/531027p1.html|archive-date=August 31, 2011|df=mdy-all}}</ref> This part of the engine works in a fundamentally similar way to the [[id Tech 3]] equivalent; however, id Tech 4 exposes a lot more of the network protocol to mod developers.<ref name="id.sdk The Code"/>

Although ''[[Doom 3]]'' only supports 4 players (and 8 in the ''[[Doom 3: Resurrection of Evil|Resurrection of Evil]]'' expansion pack), the id Tech 4 engine can be used with more players than this, with ''[[Quake 4]]'' and ''[[Enemy Territory: Quake Wars]]'' both supporting significantly more players.

== Games using id Tech 4 ==
{{More citations needed section|date=November 2010}}
[[File:Prey-Wall-Walking.png|thumb|200px|''Prey'' utilized a modified version of id Tech 4 that allowed for effects such as portals, variable gravity, and wall walking.]]

Compared to the preceding and widely used [[id Tech 3]] (''[[Quake III Arena]]'' engine) and [[id Tech 2]] (''[[Quake II]]'' engine), id Tech 4 has had less success in licensing to third parties.<ref>{{cite web|url=http://www.giantbomb.com/id-tech-4/3015-1383/|title=id Tech 4 (Concept) - Giant Bomb|access-date=November 26, 2013|archive-date=December 1, 2013|archive-url=https://web.archive.org/web/20131201100309/http://www.giantbomb.com/id-tech-4/3015-1383/|url-status=live}}</ref> This is especially apparent in comparison to its closest contemporaries, [[Unreal Engine 2]] (2002) and [[Unreal Engine 3]] (2006) from [[Epic Games]].<ref>{{cite web|title=id Tech 5|website=[[Eurogamer]] |date=August 9, 2007|url=http://www.eurogamer.net/articles/id-tech-5-interview|access-date=September 25, 2012|archive-date=March 4, 2016|archive-url=https://web.archive.org/web/20160304050507/http://www.eurogamer.net/articles/id-tech-5-interview|url-status=live}}</ref> id Software was unwilling to license their newest engine before its "parent game" ''Doom 3'' was completed. However, the unexpectedly long development time going into ''Doom 3'' from 2002-04 meant that they could not put up competition to [[Epic Games]]'s Unreal Engine 2 during that period. Many who licensed Unreal Engine 2 were thus able to make the switch to [[Unreal Engine 3]] more easily.

While id Tech 4 had taken a new direction with its dynamic [[per-pixel lighting]], this unconventional feature had steeper hardware requirements and was initially only useful in "spooky games" (until the [[MegaTexture]] addition), whereas an increasing number of developers preferred conventional engines that could render large outdoor areas. Also notable was id Tech 4's relative lack of downward scalability compared to competing FPS engines; id Tech 4 generally required a DirectX 8.0 compliant GPU such as a [[GeForce 3]]. The rival [[Source (game engine)|Source engine]]{{efn|Developed from the [[GoldSrc]] engine, itself derived from id Tech 2}} could still run on the older widespread DirectX 7 GPUs, albeit without the use of [[Shader|shaders]].

===Games using a proprietary license===
{| class="wikitable sortable"
!Year
!Title
!Developer
|-
|2004
|''[[Doom 3]]''
|[[id Software]]
|-
| rowspan="2" |2005
|''[[Doom 3: Resurrection of Evil]]''
|[[Nerve Software]]
|-
|''[[Quake 4]]''
|[[Raven Software]]
|-
|2006
|''[[Prey (2006 video game)|Prey]]''
|[[Human Head Studios]]
|-
|2007
|''[[Enemy Territory: Quake Wars]]''
|[[Splash Damage]]
|-
|2009
|''[[Wolfenstein (2009 video game)|Wolfenstein]]''
|[[Raven Software]]
|-
|2011
|''[[Brink (video game)|Brink]]''
|[[Splash Damage]]
|-
|2012
|''[[Doom 3: BFG Edition]]''
|[[id Software]]
|-
| rowspan="3" |Cancelled
|''Quake 4: Awakening''
| rowspan="2" |[[Ritual Entertainment]]
|-
|''SiN 2''<ref>{{Cite web |title=3D Realms releases video of their cancelled prototypes including SiN 2 and Bombshell FPS |url=https://www.game-debate.com/news/28578/3d-realms-releases-video-of-their-cancelled-prototypes-including-sin-2-and-bombshell-fps |url-status=live |archive-url=https://web.archive.org/web/20211203102047/https://www.game-debate.com/news/28578/3d-realms-releases-video-of-their-cancelled-prototypes-including-sin-2-and-bombshell-fps |archive-date=December 3, 2021 |access-date=April 8, 2020}}</ref>
|-
|''[[Prey 2]]''
|[[Human Head Studios]]
|}

===Games using an open-source license===
{| class="wikitable sortable"
!Year
!Title
!Developer
|-
|2013
|''[[The Dark Mod]]''{{efn|Began as an effort to recreate ''[[Thief: The Dark Project]]'' within ''Doom 3''.<ref>{{cite news|url=http://www.rockpapershotgun.com/2012/10/22/outta-dunwall-thief-remake-the-dark-mod-updates/|title=Outta Dunwall: Thief Remake The Dark Mod Updates|newspaper=Rock Paper Shotgun|date=October 22, 2012|access-date=August 25, 2015|archive-date=September 24, 2015|archive-url=https://web.archive.org/web/20150924125743/http://www.rockpapershotgun.com/2012/10/22/outta-dunwall-thief-remake-the-dark-mod-updates/|url-status=live}}</ref> It became a standalone game once the ''Doom 3'' source code was released.<ref name="dark mod">{{cite web | url = http://www.thedarkmod.com/main/ | title = The Dark Mod | date = October 13, 2011 | access-date = September 11, 2015 | archive-date = April 27, 2021 | archive-url = https://web.archive.org/web/20210427012119/https://www.thedarkmod.com/main/ | url-status = live }}</ref>}}
|
|-
|2016
|''[[Quadrilateral Cowboy]]''
|[[Blendo Games]]<ref name="ign preview">{{cite web | url = http://www.ign.com/articles/2013/02/04/what-the-hell-is-quadrilateral-cowboy | title = What the Hell is Quadrilateral Cowboy? | first = Colin | last = Campbell | date = February 4, 2013 | access-date = February 7, 2013 | publisher = [[IGN]] | archive-date = February 7, 2013 | archive-url = https://web.archive.org/web/20130207031029/http://www.ign.com/articles/2013/02/04/what-the-hell-is-quadrilateral-cowboy | url-status = live }}</ref>
|-
|2025
|''[[Skin Deep (video game)|Skin Deep]]''
|Blendo Games<ref>{{cite web | url = https://www.digitaltrends.com/gaming/skin-deep-hands-on-steam-next-fest/ | title = Skin Deep is absolutely absurd and I already love it | first = Giovanni | last = Colantonio | date = February 24, 2025 | access-date = March 10, 2025 | publisher = Digitaltrends | url-status = live }}</ref>
|}

==See also==
{{Portal|Free and open-source software|Video games}}
* [[First person shooter engine]]
* [[id Tech 3]]
* [[id Tech 5]]
* [[List of game engines]]

==Notes==
{{reflist|group=lower-alpha}}

==References==
{{Reflist|2}}

==External links==
*{{webarchive |url=https://web.archive.org/web/20081026115600/http://www.idsoftware.com/business/idtech4/ |date=October 26, 2008 |title=Official id Tech 4 licensing page }}
*[https://web.archive.org/web/20051106040328/http://www.modwiki.net/wiki/Main_Page id Tech 4 reference material]
*[https://money.cnn.com/2004/08/12/commentary/game_over/column_gaming CNN - Life after "Doom"]
*[https://github.com/id-Software/DOOM-3 Doom 3 source code on GitHub]

{{Id Software}}
{{Doom series}}
{{Quake series}}
{{Video game engines}}

[[Category:2004 software]]
[[Category:Doom (franchise)]]
[[Category:Formerly proprietary software]]
[[Category:Free game engines]]
[[Category:Game engines for Linux]]
[[Category:Id Tech]]
[[Category:Quake (series)]]
[[Category:Video game engines]]
[[Category:Virtual reality]]

Id Tech 3

2025-06-30T10:12:08Z

143.159.76.2:

{{Short description|Video game engine}}
{{lowercase title}}
{{Use mdy dates|date=August 2024}}
{{Infobox video game engine
| name = id Tech 3
| logo = Id Tech 3 logo.png
| logo size = 200px
| screenshot = Quake III Arena q3dm0.png
| caption = ''[[Quake III Arena|Quake III]]'', the engine's parent game
| collapsible =
| developer = [[id Software]]
| replaces = [[Quake II engine]]
| replaced_by = [[id Tech 4]], [[IW engine]]
| latest release version = 1.32b
| latest release date = {{Start date and age|2005|08|19}}
| repo = [https://github.com/id-Software/Quake-III-Arena github.com/id-Software/Quake-III-Arena]
| tools =
| programming language = [[C (programming language)|C]]<br>(rewritten 14% in [[C++]])
| platform = [[Microsoft Windows|Windows]], [[Classic Mac OS|Mac OS]], [[macOS|OS X]], [[Linux]], [[Dreamcast]], [[GameCube]], [[Nintendo Switch]], [[Nintendo Switch 2]], [[PlayStation 2]], [[PlayStation 3]], [[PlayStation 4]], [[Xbox (console)|Xbox]], [[Xbox 360]], [[iOS]], [[Android (operating system)|Android]]
| discontinued =
| license = [[GNU General Public License|GNU GPL-2.0-or-later]]
}}
[[File:EF2 Romulans.jpg|thumb|''[[Star Trek: Elite Force II]]'' is one of the last games to utilize the id Tech 3 engine.]]
'''id Tech 3''', popularly known as the '''''Quake III Arena'' engine''', is a [[game engine]] developed by [[id Software]] for its 1999 game ''[[Quake III Arena]]''. It has subsequently been used in numerous games. Commercially, id Tech 3 competed with early versions of the [[Unreal Engine]]; both were widely licensed. Originally proprietary, it is now [[open-source software]].

id Tech 3 is based on the earlier [[id Tech 2]], with a large amount of the code rewritten. [[id Tech 4]] was derived from id Tech 3, as was [[Infinity Ward]]'s [[IW engine]], used in ''[[Call of Duty 2]]'' onward.

At [[QuakeCon]] 2005, [[John D. Carmack|John Carmack]] announced that the id Tech 3 [[source code]] would be released under the [[GNU General Public License]] v2.0 or later, and it was released on August 19, 2005.<ref>{{Cite web |date=2005-08-19 |title=Quake III: Arena Source Released! |url=http://www.planetquake3.net/article.php?sid=2108 |url-status=dead |archive-url=https://web.archive.org/web/20051017045356/http://www.planetquake3.net/article.php?sid=2108 |archive-date=2005-10-17 |access-date=2024-12-03 |website=PlanetQuake3}}</ref> It was originally distributed via [[FTP]], and later moved to [[GitHub]].

==Features==
===Graphics===
Unlike most other game engines released at the time{{mdash}}including its main competitor, the [[Unreal Engine]]{{mdash}}id Tech 3 requires an [[OpenGL]]-compliant [[Graphics processing unit|graphics accelerator]] to run. The engine does not include a [[Software rendering|software renderer]], unlike id Tech 2.

id Tech 3 introduced [[Spline (mathematics)|spline]]-based curved surfaces in addition to planar volumes.<ref name="shader5">{{cite web | url = http://www.qeradiant.com/manual/Q3AShader_Manual/ch05/pg5_1.htm | title = Quake III Arena Shader Manual | access-date = October 1, 2006 | page = 5 | author = [[Jennell Jaquays]], Brian Hook |archive-url = https://archive.today/20060414004110/http://www.qeradiant.com/manual/Q3AShader_Manual/ch05/pg5_1.htm  |archive-date = April 14, 2006}}</ref>

The graphical technology of the game is based tightly around a [[shader]] system, where the appearance of many surfaces can be defined in text files referred to as shader [[Scripting language|scripts]]. Shaders are described and rendered as several layers. Each layer contains a texture, a "blend mode" that determines how to superimpose it over the previous layer, and texture orientation modes such as environment mapping, scrolling, and rotation. These features can readily be seen within the game, with many bright and active surfaces on each map and even character models. The shader system goes beyond visual appearance, defining the contents of volumes (e.g., a water volume is defined by applying a water shader to its surfaces), light emission, and which sound to play when a volume is trodden upon.<ref name="shader1">{{cite web | url = http://www.qeradiant.com/manual/Q3AShader_Manual/ch01/pg1_1.htm | title = Quake III Arena Shader Manual | page = 1 | access-date = October 1, 2006 | author = [[Jennell Jaquays]], Brian Hook |archive-url = https://archive.today/20060904124212/http://www.qeradiant.com/manual/Q3AShader_Manual/ch01/pg1_1.htm  |archive-date = September 4, 2006}}</ref> To assist calculation of these shaders, ''id Tech 3'' implements a specific [[fast inverse square root]] function, which attracted a significant amount of attention in the game development community for its clever use of integer operations.<ref name="Eberly 2">{{Cite web| last = Eberly| first = David| title = Fast Inverse Square Root| publisher = Geometric Tools| year = 2002| page = 2| url = http://www.geometrictools.com/Documentation/FastInverseSqrt.pdf| url-status = dead| archive-url = https://web.archive.org/web/20090224214314/http://www.geometrictools.com/Documentation/FastInverseSqrt.pdf| archive-date = February 24, 2009}}</ref><ref name="Beyond3D">{{cite web|url=http://www.beyond3d.com/content/articles/8/|title=Origin of Quake3's Fast InvSqrt()|last=Sommefeldt|first=Rys|date=November 29, 2006|work=Beyond3D|access-date=February 12, 2009|archive-date=February 9, 2009|archive-url=https://web.archive.org/web/20090209045625/http://www.beyond3d.com/content/articles/8/|url-status=live}}</ref>

===Networking===
Like id's earlier titles ''[[Doom (1993 video game)|Doom]]'' and ''[[Quake (video game)|Quake]]'', ''Quake III Arena'' features multiplayer support via features built into its engine. id Tech 3 uses a snapshot system to [[Netcode#Tick rate|relay information about game frames]] to the client over [[User Datagram Protocol|UDP]]. The server updates object interaction at a fixed rate independent of the rate that clients update the server with their actions, then attempts to send the state of all objects at that moment (the current server frame) to each client. The server attempts to omit as much information as possible about each frame, relaying only differences from the last frame the client confirmed as received ([[Delta encoding]]). All data packets are compressed by [[Huffman coding]] with static pre-calculated frequency data to reduce bandwidth use even further.<ref name="network">{{cite web | url = http://trac.bookofhook.com/bookofhook/trac.cgi/wiki/Quake3Networking | title = Book of Hook: The Quake3 Networking Model | access-date = October 1, 2006 | archive-url = https://web.archive.org/web/20061027183301/http://trac.bookofhook.com/bookofhook/trac.cgi/wiki/Quake3Networking | archive-date = October 27, 2006 | url-status = dead }}</ref>

''Quake III Arena'' has an integrated and relatively elaborate [[Cheating in online games|cheat-protection]] system called "pure server". Any client connecting to a pure server automatically has "pure mode" enabled; while pure mode is enabled, only files within data packs can be accessed. Clients are disconnected if their data packs fail one of several integrity checks. The <code>cgame.qvm</code> file, with its high potential for cheat-related modification, is subject to additional integrity checks.{{Citation needed|date=February 2007}} Developers must manually deactivate pure server to test maps or mods that are not in data packs using the PK3 file format. Later versions supplemented pure server with [[PunkBuster]] support, though all the hooks to it are absent from the source code release because PunkBuster is [[closed source]] software and including support for it in the source code release would have caused any redistributors/reusers of the code to violate the [[GPL]].<ref>{{cite web|url=http://ioquake3.org/?page=help|title=Ioquake3 Help Page|access-date=February 17, 2007|archive-date=January 11, 2016|archive-url=https://web.archive.org/web/20160111063556/http://ioquake3.org/?page=help|url-status=dead}}</ref>

==ioquake3==
[[File:Tremulous demonstrating ioquake3's automatic texture mapping feature.jpg|thumb|right|Automatic [[Specularity|specular]] and [[normal mapping]] in ioQuake3, [[Tremulous]] 1.3 prerelease client]]
Ioquake3 is a [[game engine]] project which aims to build upon the id Tech 3 [[source code]] release<ref>{{cite web|url=http://www.linuxtoday.com/news_story.php3?ltsn=2009-08-08-007-35-OS-GM|title=Complete Guide: Configure and Customise ioQuake3 in Linux|publisher=Linux Today|access-date=January 3, 2010|archive-date=March 9, 2012|archive-url=https://web.archive.org/web/20120309114038/http://www.linuxtoday.com/news_story.php3?ltsn=2009-08-08-007-35-OS-GM|url-status=dead}}</ref><ref>{{cite web |url=http://www.betanews.com/article/Quake-3-ported-to-iPod-Touch-with-tilt-controls/1208202321|title= Quake 3 ported to iPod Touch with tilt controls – Betanews|date= April 14, 2008|access-date=January 4, 2010}}</ref> in order to remove bugs, clean up source code and to add more advanced graphical and audio features via [[Simple DirectMedia Layer|SDL]] and [[OpenAL]]. ioquake3 is also intended to act as a clean base package, upon which other projects may be built. The game engine supports [[Ogg Vorbis]] format and video capture of demos in [[.avi]] format.<ref>{{cite web|url=http://www.theinquirer.net/inquirer/news/1040566/two-free-games-quake-engine-tip|archive-url=https://web.archive.org/web/20100828115411/http://www.theinquirer.net/inquirer/news/1040566/two-free-games-quake-engine-tip|url-status=unfit|archive-date=August 28, 2010|title=Two free games based on the Quake 3 engine tip up |work=[[The Inquirer]]|date=April 3, 2007|author=Valich, Theo|access-date=January 12, 2010}}</ref>

The project was started shortly after the source code release with the goal of creating a [[Software bug|bug]]-free, enhanced [[FLOSS|open source]] ''Quake III'' engine source code distribution upon which new games and projects can be based. In addition, the project aims to provide an improved environment in which ''Quake III: Arena'', the ''Team Arena'' expansion pack and all the popular [[Game modding|mods]] can be played.<ref>{{cite web|url=http://www.insidemacgames.com/news/story.php?ArticleID=14009|title=ioquake3 for OS X – Inside Mac Games|access-date=January 3, 2010|archive-date=September 24, 2015|archive-url=https://web.archive.org/web/20150924035459/http://www.insidemacgames.com/news/story.php?ArticleID=14009|url-status=dead}}</ref><ref>{{cite web|url=http://www.macsimumnews.com/index.php/archive/ioquake3_for_mac_os_x_available_for_download|title=ioquake3 for Mac OS X available for download – Macsimum News|access-date=January 3, 2010|url-status=dead|archive-url=https://web.archive.org/web/20060912084206/http://www.macsimumnews.com/index.php/archive/ioquake3_for_mac_os_x_available_for_download/|archive-date=September 12, 2006}}</ref><ref>{{cite web |url=http://www.maxiapple.com/2009/05/ioquake3-osx-clone-de-quake-iii-gratuit.html |title=IOQuake3 OSX : Clone de Quake III (gratuit) – MaxiApple.com|date=May 10, 2009|access-date=January 3, 2010}}</ref><ref>{{cite web|url=http://www.maclivre.net/2009/03/18/ioquake3-134-jogue-quake-3-no-mac-os-x/|title=IOQuake3 1.34 – Jogue Quake 3 no Mac OS X – Maclivre.net|access-date=January 4, 2010|url-status=dead|archive-url=https://web.archive.org/web/20110723193634/http://www.maclivre.net/2009/03/18/ioquake3-134-jogue-quake-3-no-mac-os-x/|archive-date=July 23, 2011}}</ref> The project added features including builtin [[VoIP]] support, [[Anaglyph image|Anaglyph stereo rendering]] (for viewing with 3D glasses), and numerous security fixes.

Ioquake3 is the basis of several game projects based on the id Tech 3 engine, such as ''[[OpenArena]]'' (mimicking ''Quake III Arena''), ''[[Tremulous]]'',<ref>{{cite web|url=http://tremulous.net/about/|title=Tremulous about page|access-date=November 4, 2009|archive-date=December 10, 2015|archive-url=https://web.archive.org/web/20151210205105/http://tremulous.net/about/|url-status=live}}</ref><ref>{{cite web|url=http://www.linuxjournal.com/article/9867|title=Quake, Meet GPL; GPL, Meet Quake – Linux Journal|access-date=January 4, 2010|archive-date=October 1, 2020|archive-url=https://web.archive.org/web/20201001060130/https://www.linuxjournal.com/article/9867|url-status=live}}</ref> ''[[Smokin' Guns]]'',<ref>{{cite web|url=http://www.jeuxlinux.fr/a269-Entretien_avec_lequipe_de_SmokinGuns.html|title=Entretien avec l'équipe de Smokin'Guns – JeuxLinux|access-date=November 4, 2009|archive-date=March 19, 2021|archive-url=https://web.archive.org/web/20210319053021/https://www.jeuxlinux.fr/a269-Entretien_avec_lequipe_de_SmokinGuns.html|url-status=live}}</ref> ''[[Urban Terror]]'',<ref>{{cite web |url=http://www.urbanterror.info/support/manual/game/ |title=Urban Terror manual|access-date=May 18, 2015}}</ref><ref>{{cite web |url=http://www.theinquirer.net/inquirer/news/1040566/two-free-games-quake-engine-tip |archive-url=https://web.archive.org/web/20100828115411/http://www.theinquirer.net/inquirer/news/1040566/two-free-games-quake-engine-tip |url-status=unfit |archive-date=August 28, 2010 |title=Two free games based on the Quake 3 engine tip up – The Inquirer|access-date=January 4, 2010}}</ref> ''Turtle Arena'' and ''[[World of Padman]]''<ref>{{cite web|url=http://games.slashdot.org/article.pl?sid=07/04/06/1638232|title=A Look At Free Quake3 Engine Based Games – Slashdot|date=April 6, 2007 |access-date=January 3, 2010|archive-date=March 19, 2021|archive-url=https://web.archive.org/web/20210319053020/https://games.slashdot.org/story/07/04/06/1638232/a-look-at-free-quake3-engine-based-games|url-status=live}}</ref><ref>{{cite web|url=http://www.linux-gamers.net/modules/smartsection/item.php?itemid=81&keywords=ioquake3 |title=Comparison of free software shooters – linuX-gamers.net |access-date=January 4, 2010 }}{{dead link|date=June 2016|bot=medic}}{{cbignore|bot=medic}}</ref> and game engine projects such as efport (a ''[[Star Trek: Voyager – Elite Force#Versions and sequels|Star Trek: Voyager – Elite Force Holomatch]]'' clone), ioJedi Outcast, ioJedi Academy, ioDoom3, and [[OpenMoHAA]]. The engine and its associated games have been included in several [[Linux]] and [[BSD]] distributions. The cMod engine derived from the earlier ''Elite Force'' port was used to package the 20th anniversary [[Star Trek: Voyager – Elite Force#Freeware release|freeware release]] of the game for [[Windows]] and [[Linux]].<ref>{{cite web|url=https://www.wepc.com/news/star-trek-voyager-elite-force-holomatch-gets-free-20th-anniversary-re-release/|title=Star Trek: Voyager Elite Force Holomatch Gets Free 20th Anniversary Re-Release|first=Lewie|last=Procter|website=wePC|date=August 13, 2020|access-date=March 25, 2023}}</ref>

The source code for the ''[[Return to Castle Wolfenstein]]'' and ''[[Wolfenstein: Enemy Territory]]'' engines was released under [[GNU General Public License|GNU GPL-3.0-or-later]] on August 12, 2010.<ref>{{cite web |url=ftp://ftp.idsoftware.com/idstuff/source/ |archive-url=https://web.archive.org/web/20151202080952/ftp://ftp.idsoftware.com/idstuff/source/ |archive-date=2015-12-02 |url-status=dead |title=FTP link |work=ftp.idsoftware.com }}</ref> The ioquake3 developers announced the start of other engine projects.<ref>{{cite web | url = https://www.phoronix.com/scan.php?page=news_item&px=ODUwNA | title = id Software Open-Sources ET, RTCW | access-date = August 13, 2010 | last = Larabel | first = Michael | date = June 13, 2010 | publisher = [[Phoronix]] | author-link = Michael Larabel | archive-date = August 16, 2010 | archive-url = https://web.archive.org/web/20100816034701/http://www.phoronix.com/scan.php?page=news_item&px=ODUwNA | url-status = live }}</ref>

The ioquake3 project has been used academic research such as Stanford University's Center for Computer Research in Music and Acoustics (CCRMA),<ref>{{cite web |url=https://ccrma.stanford.edu/~rob/papers/hamilton-ICMC2008-q3osc.pdf |title=Q3osc research paper |access-date=January 9, 2010 |archive-date=March 19, 2021 |archive-url=https://web.archive.org/web/20210319053031/https://ccrma.stanford.edu/~rob/papers/hamilton-ICMC2008-q3osc.pdf |url-status=live }}</ref><ref>{{cite web |url=https://ccrma.stanford.edu/wiki/Q3osc |title=Q3osc wiki |access-date=January 9, 2010}}</ref> Notre Dame as the foundation for VR research,<ref>{{cite web |url=http://www.cse.nd.edu/Reports/2008/TR-2008-11.pdf |title=A Survey of Collaborative Virtual Environment Technologies |access-date=January 9, 2010 |archive-date=October 10, 2015 |archive-url=https://web.archive.org/web/20151010134157/http://www.cse.nd.edu/Reports/2008/TR-2008-11.pdf |url-status=dead }}</ref> and Swinburne University of Technology's Centre for Advanced Internet Architectures.<ref>{{cite web |url=http://caia.swin.edu.au/reports/070808A/CAIA-TR-070808A.pdf |title=L3DGEWorld 2.1 Input & Output Specifications |access-date=January 9, 2010 |archive-date=October 5, 2011 |archive-url=https://web.archive.org/web/20111005205807/http://caia.swin.edu.au/reports/070808A/CAIA-TR-070808A.pdf |url-status=live }}</ref><ref>{{cite web |url=http://caia.swin.edu.au/urp/l3dge/tools/l3dgeworld/index.html |title=L3DGEWorld 2.3 |access-date=January 9, 2010 |archive-date=October 5, 2011 |archive-url=https://web.archive.org/web/20111005205914/http://caia.swin.edu.au/urp/l3dge/tools/l3dgeworld/index.html |url-status=live }}</ref> Collaborative efforts from researchers at Carnegie Mellon University and the University of Toronto use ioquake3 as a platform for their published research.<ref>{{cite web |url=http://www.vmware.com/files/pdf/vee.pdf |title=VMM-Independent Graphics Acceleration |access-date=January 9, 2010 |url-status=dead |archive-url=https://web.archive.org/web/20091009154854/http://www.vmware.com/files/pdf/vee.pdf |archive-date=October 9, 2009 }}</ref><ref>{{cite book |url=http://portal.acm.org/citation.cfm?id=1254816 |title=VMM article in ACM |date=June 13, 2007 | isbn = 978-1-59593-630-1|pages= 33–43 |doi=10.1145/1254810.1254816 |s2cid=655357 |access-date=January 9, 2010}}</ref> Students have used ioquake3 as the basis for advanced graphics work for their theses, such as Stephan Reiter's work<ref>{{cite web |url=http://llvm.org/pubs/2008-06-Reiter-Thesis.html |title=Real-time Ray Tracing of Dynamic Scenes |access-date=April 22, 2012}}</ref><ref>{{cite web |url=http://llvm.org/pubs/2008-08-RTCodegen.html |title=Run-Time Code Generation for Materials |access-date=April 22, 2012}}</ref> which has been noted at the LLVM project<ref>{{cite web |url=http://llvm.org/Users.html |title=LLVM Users, Open Source Projects |access-date=January 9, 2010 |archive-date=February 23, 2021 |archive-url=https://web.archive.org/web/20210223230411/https://llvm.org/Users.html |url-status=live }}</ref> due to his synthesis of the ioquake3 engine, ray-tracing rendering technique, and LLVM.

The project has since received forks, such as Quake3e,<ref>{{cite web|url=https://www.phoronix.com/news/V3DV-More-Backend-Opts|title=V3DV Vulkan Driver Enjoys More Optimizations To Help The Raspberry Pi 4|first=Michael|last=Larabel|date=March 16, 2021|access-date=August 9, 2024|website=[[Phoronix]]}}</ref> Spearmint,<ref>{{cite web|url=https://www.phoronix.com/news/Spearmint-1.0-Next-Month|title=Ioquake3-Derived Spearmint 1.0 Engine Coming Next Month, But Ceasing Development|first=Michael|last=Larabel|date=September 19, 2018|access-date=August 9, 2024|website=[[Phoronix]]}}</ref> and vkQuake3.<ref>{{cite web|url=https://www.tomshardware.com/news/nvidia-engineer-vulkan-driver-raspberry-pi-quake-iii-100-fps|title=Nvidia Engineer's Vulkan Driver For Raspberry Pi Runs Quake III Over 100 FPS at 720p|first=Zhiye|last=Liu|date=June 20, 2020|access-date=July 20, 2024|website=[[Tom's Hardware]]}}</ref><ref>{{cite web|url=https://www.phoronix.com/news/Gfx-rs-Portability-vkQuake|title=The Rust Vulkan "Gfx-rs" Portability Layer Can Now Run vkQuake3|first=Michael|last=Larabel|date=March 27, 2019|access-date=July 21, 2024|website=[[Phoronix]]}}</ref>

Other derived engines include the [[Unvanquished (video game)#Engine|Daemon]] engine used by ''[[Unvanquished (video game)|Unvanquished]]'',<ref>{{cite web|url=http://www.phoronix.com/scan.php?page=news_item&px=MTEzMTM|title=Unvanquished: A Very Promising Open-Source Game|date=July 1, 2012|access-date=July 7, 2015|website=[[Phoronix]]|author=Michael Larrabel}}</ref><ref>{{cite web|url=https://www.phoronix.com/news/MTQ2MjM|title=Unvanquished Is Rewriting, Modernizing The Quake 3 Engine|first=Michael|last=Larabel|date=September 15, 2013|access-date=August 9, 2024|website=[[Phoronix]]}}</ref><ref>{{cite web|url=https://www.phoronix.com/news/Daemon-Easy-For-Others|title=Unvanquished Makes Its Open-Source Engine Easy For Other Games|first=Michael|last=Larabel|date=August 3, 2015|access-date=August 9, 2024|website=[[Phoronix]]}}</ref> as well as competing source ports like XreaL,<ref>{{cite web|url=https://www.phoronix.com/review/xreal_engine|title=XreaL: The Most Advanced Open-Source Game Engine?|first=Michael|last=Larabel|date=April 9, 2009|access-date=July 21, 2024|website=[[Phoronix]]}}</ref><ref>{{cite web|url=https://www.phoronix.com/news/MTI0MDE|title=The State Of XReaL, OpenWolf Game Engines|first=Michael|last=Larabel|date=December 1, 2012|access-date=July 21, 2024|website=[[Phoronix]]}}</ref> Kwaak3 for [[Android (operating system)|Android]]<ref>{{cite web|url=https://techcrunch.com/2010/02/25/quake-3-android-style/|title=Quake 3, Android style|date=February 25, 2010|access-date=July 21, 2024|website=[[TechCrunch]]}}</ref><ref>{{cite web|url=https://www.phoronix.com/news/ODAwOA|title=Quake 3 Comes To Google's Android Platform|first=Michael|last=Larabel|date=February 23, 2010|access-date=July 21, 2024|website=[[Phoronix]]}}</ref><ref>{{cite web|url=https://www.pocketgamer.com/quake-iii/quake-3-ported-to-android/|title=Quake 3 ported to Android|first=Spanner|last=Spencer|date=February 26, 2010|access-date=July 21, 2024|website=Pocket Gamer}}</ref><ref>{{cite web|url=https://www.engadget.com/2010-02-25-quake-3-ported-to-android-shows-off-droids-graphical-prowess.html|title=Quake 3 ported to Android, shows off Droid's graphical prowess (video)|first=Vlad|last=Savov|date=February 25, 2010|access-date=July 21, 2024|website=[[Engadget]]}}</ref><ref>{{cite web|url=https://phandroid.com/2010/02/24/quake-3-successfully-ported-to-android-2-0-devices/|title=Quake 3 Successfully Ported To Android 2.0 Devices|first=Anthony|last=Perez|date=February 24, 2010|access-date=July 21, 2024|website=Phanadroid}}</ref><ref>{{cite web|url=https://phandroid.com/2010/05/10/quake-3-finally-ported-to-the-nexus-one/|title=Quake 3 Finally Ported To The Nexus One|first=Quentyn|last=Kennemer|date=May 10, 2010|access-date=July 21, 2024|website=Phanadroid}}</ref> and Quake-3-Android-Port-QIII4A.<ref>{{cite web|url=https://www.xda-developers.com/how-to-play-return-to-castle-wolfenstein-doom-3-and-quake-3-with-arena-on-your-android-device/|title=How to play Return to Castle Wolfenstein, Doom 3, and Quake 3 (with Arena) on your Android device|first=Mishaal|last=Rahman|date=May 16, 2017|access-date=July 21, 2024|website=[[XDA Developers]]}}</ref>

==Games==
{| class="wikitable sortable"
!Year
!Title
!Developer
!Notes
|-
| 1999
| ''[[Quake III Arena]]''
| [[id Software]]
|
|-
| rowspan="4" | 2000
| ''[[Heavy Metal: F.A.K.K. 2]]''
| [[Ritual Entertainment]]
| ÜberTools
|-
| ''[[Star Trek: Voyager – Elite Force]]''
| [[Raven Software]]
|
|-
| ''[[American McGee's Alice]]''
| [[Rogue Entertainment]]
| ÜberTools
|-
|''[[Quake III: Team Arena]]''
| [[id Software]]
|
|-
| rowspan="3" | 2001
|''[[Quake III Revolution]]''
| [[Bullfrog Productions]]
|
|-
| ''[[James Bond 007: Agent Under Fire]]''
| [[EA Redwood Shores]]
| ÜberTools
|-
| ''[[Return to Castle Wolfenstein]]''
| [[Gray Matter Studios]] {{Small|{{Abbr|(SP)|Single-player}}}} <br>[[Nerve Software]] {{Small|{{Abbr|(MP)|Multiplayer}}}}
|
|-
| rowspan="4" | 2002
| ''[[Medal of Honor: Allied Assault]]''
| [[2015, Inc.]]
| ÜberTools
|-
|''[[Star Wars Jedi Knight II: Jedi Outcast]]''
| [[Raven Software]]
|
|-
|''[[Soldier of Fortune II: Double Helix]]''
| [[Raven Software]]
|
|-
| ''[[Medal of Honor: Allied Assault - Spearhead]]''
| [[EA Los Angeles]]
| ÜberTools
|-
| rowspan="5" | 2003
| ''[[Wolfenstein: Enemy Territory]]''
| [[Splash Damage]]
|
|-
| ''[[Star Trek: Elite Force II]]''
| [[Ritual Entertainment]]
| ÜberTools
|-
| ''[[Medal of Honor: Allied Assault - Breakthrough]]''
| [[TKO Software]]
| ÜberTools
|-
| ''[[Star Wars Jedi Knight: Jedi Academy]]''
| [[Raven Software]]
|
|-
| ''[[Call of Duty (video game)|Call of Duty]]''
| [[Infinity Ward]]
| ÜberTools
|-
| rowspan="3" |2004
| ''[[James Bond 007: Everything or Nothing]]''
| [[EA Redwood Shores]]
| ÜberTools
|-
| ''[[Call of Duty: United Offensive]]''
| [[Gray Matter Studios]]<br>[[Treyarch]]
| ÜberTools
|-
| ''[[Medal of Honor: Pacific Assault]]''
| [[EA Los Angeles]]
| ÜberTools
|-
| 2008
| ''[[Iron Grip: Warlord]]''
| [[ISOTX]]
|
|-
| rowspan=2| 2009
|''[[Dark Salvation]]''
| Mangled Eye Studios
|
|-
|''[[CoD Classic|Call of Duty Classic]]''
| [[Infinity Ward]]
| ÜberTools
|-
| 2010
| ''[[Quake Live]]''
| [[id Software]]
|
|-
| rowspan="2" |Cancelled
|''[[Severity (video game)|Severity]]''
| [[Escalation Studios]]
|
|-
| ''Trinity: The Shatter Effect''
| [[Gray Matter Studios]]
|
|}

==See also==
{{Portal|Free and open-source software|Video games}}
* [[id Tech 2]]
* [[id Tech 4]]
* [[List of game engines]]
* [[Quake modding]]

==References==
{{Reflist}}

==External links==
*{{cite web|url=http://www.idsoftware.com/business/idtech3/ |title=Official id Tech 3 licensing page |access-date=July 6, 2012 |url-status=bot: unknown |archive-url=https://web.archive.org/web/20091108191718/http://www.idsoftware.com/business/idtech3/ |archive-date=November 8, 2009 }}
*[https://web.archive.org/web/20151202082819/ftp://ftp.idsoftware.com/idstuff/source/quake3-1.32b-source.zip Original Quake III source code repository (id Tech 3)] on idsoftware.com{{dead link|date=April 2017 |bot=InternetArchiveBot |fix-attempted=yes }}
*[https://github.com/id-Software/Quake-III-Arena id's current Quake III source code repository (id Tech 3)] on [[github.com]]
*[http://ioquake3.org/ ioquake3 project page], community continuation

{{Id Software}}
{{Quake}}
{{Call of Duty series}}
{{Video game engines}}

[[Category:1999 software]]
[[Category:Formerly proprietary software]]
[[Category:Free game engines]]
[[Category:Game engines for Linux]]
[[Category:Id Tech]]
[[Category:Quake (series)]]
[[Category:Virtual reality]]