Open source video games
Encyclopedia
Source code
In computer science, source code is text written using the format and syntax of the programming language that it is being written in. Such a language is specially designed to facilitate the work of computer programmers, who specify the actions to be performed by a computer mostly by writing source...
is open source
Open source
The term open source describes practices in production and development that promote access to the end product's source materials. Some consider open source a philosophy, others consider it a pragmatic methodology...
. They are often freely distributable and sometimes cross-platform
Cross-platform
In computing, cross-platform, or multi-platform, is an attribute conferred to computer software or computing methods and concepts that are implemented and inter-operate on multiple computer platforms...
compatible. Many are included in Linux distribution
Linux distribution
A Linux distribution is a member of the family of Unix-like operating systems built on top of the Linux kernel. Such distributions are operating systems including a large collection of software applications such as word processors, spreadsheets, media players, and database applications...
s as a result.
Open source games which are free software
Free software
Free software, software libre or libre software is software that can be used, studied, and modified without restriction, and which can be copied and redistributed in modified or unmodified form either without restriction, or with restrictions that only ensure that further recipients can also do...
and contain exclusively free content
Free content
Free content, or free information, is any kind of functional work, artwork, or other creative content that meets the definition of a free cultural work...
are called free games. Most free games are open source, but not all open source games are free software; some open source games contain proprietary non-free content.
Background
In general free games are developed by small groups of people in their free time, without aiming for profitProfit (economics)
In economics, the term profit has two related but distinct meanings. Normal profit represents the total opportunity costs of a venture to an entrepreneur or investor, whilst economic profit In economics, the term profit has two related but distinct meanings. Normal profit represents the total...
. Some free games are based on formerly proprietary
Proprietary software
Proprietary software is computer software licensed under exclusive legal right of the copyright holder. The licensee is given the right to use the software under certain conditions, while restricted from other uses, such as modification, further distribution, or reverse engineering.Complementary...
projects, whose source code
Source code
In computer science, source code is text written using the format and syntax of the programming language that it is being written in. Such a language is specially designed to facilitate the work of computer programmers, who specify the actions to be performed by a computer mostly by writing source...
was released as free and open source software and game data as free and open content. An example is Warzone 2100
Warzone 2100
Warzone 2100 is an open source real-time strategy and real-time tactics hybrid computer game, originally developed by Pumpkin Studios and published by Eidos Interactive...
. Almost all free games are volunteer run projects, and as such free game developers are principally hobbyists and enthusiasts. The consequence of this is that most games take many years to mature and that means there are only a few complete high quality free games. One of the challenges to building high quality content for games is it often requires expensive tools like 3D-modeller or a toolset for level design
Level design
Level design, environment design or game mapping is a discipline of game development involving creation of video game levels—locales, stages, or missions. This is commonly done using level editor, a game development software designed for building levels; however some games feature built-in...
. As open source applications like Blender
Blender (software)
Blender is a free and open-source 3D computer graphics software product used for creating animated films, visual effects, interactive 3D applications or video games. The current release version is 2.60, and was released on October 19, 2011...
mature and professional tools like GtkRadiant
GtkRadiant
GtkRadiant is a level design program developed by id Software and Loki Software. It is used to create maps for a number of video games. It is maintained by id Software together with a number of volunteers.-History:...
are published under open licenses, this is becoming less of an issue.
Beginnings and early games
Free software
Free software, software libre or libre software is software that can be used, studied, and modified without restriction, and which can be copied and redistributed in modified or unmodified form either without restriction, or with restrictions that only ensure that further recipients can also do...
was an unconscious occurrence during the creation of early computer games, particularity for earlier Unix
Unix
Unix is a multitasking, multi-user computer operating system originally developed in 1969 by a group of AT&T employees at Bell Labs, including Ken Thompson, Dennis Ritchie, Brian Kernighan, Douglas McIlroy, and Joe Ossanna...
games. These are mostly original or clone arcade games and text adventures. A notable example of this is BSD Games, a collection of interactive fiction
Interactive fiction
Interactive fiction, often abbreviated IF, describes software simulating environments in which players use text commands to control characters and influence the environment. Works in this form can be understood as literary narratives and as video games. In common usage, the term refers to text...
titles. Game fan communities such as the modding community do include some aspects of free software, such as sharing mods across community sites, sometimes with free to use media made for the modification. With the rise of proprietary software
Proprietary software
Proprietary software is computer software licensed under exclusive legal right of the copyright holder. The licensee is given the right to use the software under certain conditions, while restricted from other uses, such as modification, further distribution, or reverse engineering.Complementary...
in the mid to late 1980s, games became more and more proprietary. However, this also led to the first deliberately free games such as GNU Chess
GNU Chess
GNU Chess is a computer program which plays a full game of chess against a human or other computer program.GNU Chess is one of the oldest computer chess programs for Unix-based computers and one of the earliest available with full source code....
of the GNU Project
GNU Project
The GNU Project is a free software, mass collaboration project, announced on September 27, 1983, by Richard Stallman at MIT. It initiated GNU operating system development in January, 1984...
, part of whose goal is to create a complete free software system, games included. More advanced free gaming projects emerged, such as NetHack
NetHack
NetHack is a single-player roguelike video game originally released in 1987. It is a descendant of an earlier game called Hack , which is a descendant of Rogue...
and Netrek
Netrek
Netrek is an Internet game for up to 16 players, written almost entirely in cross-platform open source software. It combines features of multi-directional shooters and team-based real-time strategy games...
, many still developed and played today in front-ends such as Vulture's Eye
Falcon's Eye
Falcon's Eye is a version of the computer game NetHack which introduces isometric graphics and mouse control. Falcon's Eye has been praised for improving Nethacks visuals and audio to an almost commercial level and has been noted as among some of the best free games available by Linux...
.
As PC gaming began to rise in the late 1980s and early 1990s, free gaming also advanced. More complicated games utilizing the X Window System
X Window System
The X window system is a computer software system and network protocol that provides a basis for graphical user interfaces and rich input device capability for networked computers...
for graphics started to emerge, most beginning with the signature letter X. These included XBill
XBill
XBill is an arcade style game for the X Window System. It was very popular among Linux gamers at the end of the 1990s, beating out Quake, though not Quake II, as Linux Journal reader's favourite Linux game in 1999....
, XEvil
XEvil
XEvil is a free software side-scrolling computer game developed by Steve Hardt at M.I.T. The game is a free-for-all deathmatch that pits any player against another player or a computer player...
, xbattle
Xbattle
xbattle is a multi-player real time strategy game released in 1991 by Steve Lehar and Greg Lesher.The game was originally written for unix systems using the X Window System. Many military-type scenarios can be played out in this game. The board is very generic, consisting of repeated geometric...
, Xconq
Xconq
Xconq is an open source computer strategy game and game engine. First posted to comp.sources.games in 1987, it is notable as one of the first multi-player games to be released for the X Window System...
and XPilot
XPilot
XPilot is a multiplayer computer game. It is open source and runs on many platforms. Although its 2D graphics have improved over time, they still resemble the style of Thrust. Gameplay includes Capture the Flag, base defense, racing and deathmatches...
. XBill is notable as one of the earliest free gaming titles to feature an activist theme of halting proprietary software adoption. This theme was in echoed in later titles such as FreeDroidRPG. XEvil
XEvil
XEvil is a free software side-scrolling computer game developed by Steve Hardt at M.I.T. The game is a free-for-all deathmatch that pits any player against another player or a computer player...
followed the development cycle of many early pieces of free software, having originally been developed as a university project, although it was freeware
Freeware
Freeware is computer software that is available for use at no cost or for an optional fee, but usually with one or more restricted usage rights. Freeware is in contrast to commercial software, which is typically sold for profit, but might be distributed for a business or commercial purpose in the...
for a while. The game was also one of the first free titles to feature controversial subject matter
Video game controversy
Violent video game debates often center on topics such as video game graphic violence, sex and sexism, violent and gory scenes, partial or full nudity, portrayal of criminal behavior, racism, and other provocative and objectionable material. Video games have been studied for links to addiction and...
such as graphic violence
Graphic violence
Graphic violence is the depiction of especially vivid, brutal and realistic acts of violence in visual media such as literature, film, television, and video games...
and drug use
Recreational drug use
Recreational drug use is the use of a drug, usually psychoactive, with the intention of creating or enhancing recreational experience. Such use is controversial, however, often being considered to be also drug abuse, and it is often illegal...
. Rocks'n'Diamonds
Rocks'n'Diamonds
Rocks'n'Diamonds is a scrolling tile-based computer puzzle game that can be described as a combined Boulder Dash, Supaplex, Emerald Mine, and Sokoban clone. It is a freeware and open source video game created by Artsoft Entertainment and designed by Holger Schemel...
is another earlier free software game, and one of the first for Linux
Linux
Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
.
The FreeCiv
Freeciv
Freeciv is a multiplayer , turn-based strategy game for workstations and personal computers inspired by the commercial proprietary Sid Meier's Civilization series...
project was started in 1995 and gave rise to another new style of free game development. Similar to the cooperative nature of the Linux kernel
Linux kernel
The Linux kernel is an operating system kernel used by the Linux family of Unix-like operating systems. It is one of the most prominent examples of free and open source software....
development, FreeCiv was extended by many volunteers, rather than only one or two authors. It had started out as a small university student project but then branched out into its current form and is still being developed today. FreeCiv also proved to be one of the earliest hit free software games, and was among the first to be included with Linux distributions, a system commonly known now as a source of peer review or selection of quality for free gaming projects, though magazines, news sources and websites have also started noting free games, often in listings. FreeCiv and other archetypes have led to the development of many other clones of popular proprietary games. BZFlag
BZFlag
BZFlag is a free, open source, online multiplayer video game.A first-person tank battle game, similar in concept to Battlezone, it was originally written by Chris Schoeneman for SGI graphics workstations running IRIX, but has now been ported to other operating systems including...
, first worked on a few years earlier, is another project that had humble beginnings but grew into a popular and heavily developed project.
3D games and source releases
Descent (video game)
Descent is a 3D first-person shooter video game developed by Parallax Software and released by Interplay Entertainment Corp. in 1995. The game features six degrees of freedom gameplay and garnered several expansion packs...
brought in the age of three-dimensional games in the early to mid 1990s, and free games started to make the switch themselves. Tuxedo T. Penguin: A Quest for Herring by Steve Baker, a game featuring the Linux mascot Tux
Tux
Tux is a penguin character and the official mascot of the Linux kernel. Originally created as an entry to a Linux logo competition, Tux is the most commonly used icon for Linux, although different Linux distributions depict Tux in various styles. In video games featuring the character, female...
, was an early example of a three-dimensional free software game. He and his son Oliver would later create other popular 3D free games and clones such as TuxKart
TuxKart
TuxKart is an open source game for Linux by Steve Baker. Each character in the game has a track named after them. Tracks include Tux's Tollway, Gown's Bow, Geeko Peak, BSOD's Castle, Oliver's Math Class, and Shifting Sands....
and contribute to those by other developers such as Tux Racer
Tux Racer
Tux Racer is a Free Software 3D computer game starring the Linux mascot, Tux the penguin. In the game, the player controls Tux as he slides down a course of snow and ice collecting herring. Sliding on ice makes Tux go faster, while sliding on snow allows for more maneuverability and sliding on...
. The Genesis3D
Genesis3D
Genesis3D was a project by Eclipse Entertainment to create a real-time 3D engine for Microsoft Windows. It was released as source code in 1998. The first released version supported hardware acceleration and a software renderer...
engine project and the Cube project also spawned other 3D free software engines and games. FlightGear
FlightGear
FlightGear Flight Simulator is a free, open-source multi-platform flight simulator developed by the FlightGear project since 1997....
is another good example, especially noting that it is not a shooter engine but a flight simulator
Flight simulator
A flight simulator is a device that artificially re-creates aircraft flight and various aspects of the flight environment. This includes the equations that govern how aircraft fly, how they react to applications of their controls and other aircraft systems, and how they react to the external...
.
id Software
Id Software
Id Software is an American video game development company with its headquarters in Richardson, Texas. The company was founded in 1991 by four members of the computer company Softdisk: programmers John Carmack and John Romero, game designer Tom Hall, and artist Adrian Carmack...
, an early entrant into commercial Linux gaming
Linux gaming
Linux gaming refers to playing or developing video games for the Linux operating systems.- Background :Linux gaming refers to all game titles that can run on Linux based operating systems. This can refer to free / open source games, which may also be commercial, that run natively on Linux, or...
, would also prove to be an early supporter of free gaming when John D. Carmack released the source code for Wolfenstein 3D
Wolfenstein 3D engine
The Wolfenstein 3D engine is the engine that powers Wolfenstein 3D.The biggest part of the engine is programmed by John Carmack. It is written in C and x86 assembly language. It features graphics , sound , player physics and game control.-Features and limitations:To render the walls in pseudo-3D,...
and Doom
Id Tech 1
- See also :*List of game engines*First person shooter engine*id Tech*Doom engine*Doom *Quake engine*Quake *List of first-person shooter engines...
, first under a custom license and then later the GPL
GNU General Public License
The GNU General Public License is the most widely used free software license, originally written by Richard Stallman for the GNU Project....
. This was followed by the release of Quake engine
Quake engine
The Quake engine is the game engine that was written to power 1996's Quake, written by id Software. It featured true 3D real-time rendering and is now licensed under the terms of the GNU General Public License ....
, id Tech 2 and id Tech 3. This led not only to source port
Source port
A source port is a software project based on the source code of a computer game's engine that allows the game to be played on operating systems or computing platforms with which the game was not originally compatible. Source ports are created by fans after the original developer hands over the...
s that allowed the playing of the non-free games based on these engines (plus fan added enhancements) on free engines and systems, but also to new free games such as Freedoom
Freedoom
Freedoom is a free Doom engine based first-person shooter game currently under development. The game is currently in an alpha stage and many features are missing, for example some monsters and other sprites are replaced by placeholder images, some levels are missing, and some levels have no music....
, Nexuiz
Nexuiz
Nexuiz is a free first-person shooter video game developed and published by Alientrap Software. It is free and open-source software and is distributed under the GNU General Public License . Version 1.0 of the game was released on May 31, 2005. The current version, 2.5.2, was released on October 1,...
, Tremulous
Tremulous
Tremulous is a free and open source team-based first-person shooter with real-time strategy elements.The game features two opposing teams: humans and aliens. Each team must attack the enemy's base and team members, while defending their own base...
, and OpenArena
OpenArena
OpenArena is a free and open source first-person shooter computer game based heavily on the Quake III Arena style deathmatch. The OpenArena project was established on August 19, 2005, the day after the id Tech 3 GPL source code release...
. Freeware
Freeware
Freeware is computer software that is available for use at no cost or for an optional fee, but usually with one or more restricted usage rights. Freeware is in contrast to commercial software, which is typically sold for profit, but might be distributed for a business or commercial purpose in the...
games, such as CodeRED: Alien Arena
CodeRED: Alien Arena
Alien Arena is a free, stand-alone first-person shooter computer game based on source code released by id Software. Begun by COR Entertainment in 2004, the game combines a 1950s-era sci-fi atmosphere with gameplay similar to the Quake, Doom, and Unreal Tournament series...
, Warsow, World of Padman
World of Padman
World of Padman is an open source first-person shooter computer game available in both English and German. Originally it was a modification for the game Quake III Arena titled PadMod created in the year 2004. After the source code for Quake III Arena was released, the game became standalone...
and Urban Terror
Urban Terror
Urban Terror, commonly abbreviated as UrT, is a free multi-player first person shooter game developed by FrozenSand. Originally a total conversion of id Software's Quake III Arena, FrozenSand released Urban Terror as a free standalone game in 2007 utilizing ioquake3 as an engine...
, have also taken advantage of these free engines and sometimes have given code back to the community. id Tech 4 is expected to be released as free software, even amongst patent concerns from Creative Labs. Development and editing tools are also commonly released freely, such as GtkRadiant
GtkRadiant
GtkRadiant is a level design program developed by id Software and Loki Software. It is used to create maps for a number of video games. It is maintained by id Software together with a number of volunteers.-History:...
.
id partners and related, such as Raven Software
Raven Software
Raven Software is an American video game developer. The company was founded in 1990 by brothers Brian and Steve Raffel. In 1997, Raven made an exclusive publishing deal with Activision and was subsequently acquired by them...
, Bungie Software and 3D Realms
3D Realms
3D Realms is a current video game publisher and former video game developer based in Garland, Texas, United States, established in 1987...
, as well as several of the developers who participated in the Humble Indie Bundle
Humble Indie Bundle
The Humble Indie Bundles or Humble Bundles are a series of game bundles, that are sold and distributed online at a price determined by the purchaser. The games are multi-platform, DRM-free, and independently developed, and buyers can set the revenue split between the developers, charities and...
, have also released code and it is now accepted practice for some mainstream game developers to release legacy source code. Formerly proprietary games such as Jump 'n bump
Jump 'n Bump
Jump 'n Bump is a 1998 freeware MS-DOS platform video game, written in C and Assembly language by Brainchild Design. The source code was released in 1999, and the game has since been ported to a number of other operating systems, with the release of a SDL version.The graphics were made with Deluxe...
, Meritous
Meritous
Meritous is a freeware game made by Lancer-X/ASCEAI for the PC. It's an "action-adventure dungeon crawl" about the psi user Merit who ventures into Orcus dome to correct the problems in the psi flow.-Gameplay:...
, Warzone 2100
Warzone 2100
Warzone 2100 is an open source real-time strategy and real-time tactics hybrid computer game, originally developed by Pumpkin Studios and published by Eidos Interactive...
, HoverRace
HoverRace
HoverRace is a game created by GrokkSoft in 1996 as shareware. GrokkSoft claimed it was the first internet-based online multiplayer game. The source code was released to the public in 2006 and HoverRace.com maintains a version which is still under active development.- Gameplay :HoverRace allows...
and Abuse have even been entirely released freely, including multimedia assets and levels. Some games are mostly free software but contain some proprietary content such as the Cube sequel, Sauerbraten or the former Quake III Arena
Quake III Arena
Quake III Arena , is a multiplayer first-person shooter video game released on December 2, 1999. The game was developed by id Software and featured music composed by Sonic Mayhem and Front Line Assembly...
mod Smokin' Guns
Smokin' Guns
Smokin' Guns is a first-person shooter video game. Smokin' Guns is intended to be a semi-realistic simulation of the American Old West's atmosphere and was developed on id Software's Quake III Arena Engine...
, but some developers desire and/or work on replacing these with free content. Primarily proprietary developers have also helped free gaming by creating free libraries. Loki Software
Loki Software
Loki Software, Inc. was a software firm based in Tustin, California, United States, that ported several video games from Microsoft Windows to Linux...
helped create and maintain the Simple DirectMedia Layer
Simple DirectMedia Layer
Simple DirectMedia Layer is a cross-platform, free and open source multimedia library written in C that presents a simple interface to various platforms' graphics, sound, and input devices....
and OpenAL
OpenAL
OpenAL is a cross-platform audio API. It is designed for efficient rendering of multichannel three dimensional positional audio. Its API style and conventions deliberately resemble those of OpenGL.- History :...
libraries and Linux Game Publishing
Linux Game Publishing
Linux Game Publishing is a software company based in Nottingham in England. It ports, publishes and sells video games running on Linux operating systems. As well as porting games, LGP also sponsors the development of Grapple, a free software network library for games...
created and maintain the free network layer Grapple
Grapple (network layer)
Grapple is a free software package for adding multiplayer support to computer games and applications. It uses Internet protocols, supporting both TCP/IP and UDP/IP...
. LGP also avoids publishing games similar to popular free titles. Many libraries/infrastructures have been created without corporate assistance however, such as the online gaming system GGZ Gaming Zone
GGZ Gaming Zone
GGZ Gaming Zone is a free online game infrastructure project founded in the year 2000. Dozens of games have been developed, in addition to gaming tools, a chat bot and other utilities.-Overview:...
. In addition, various game creators are free software such as the ZZT
ZZT
ZZT is an ANSI character-based computer game, created in 1991 by Tim Sweeney of Epic Games , who later designed Unreal. It remains a popular DOS game creation system. ZZT itself is not an acronym for anything; its title was simply chosen so it would always appear at the very bottom of newsgroup...
remake MegaZeux
MegaZeux
MegaZeux, or MZX, is a game creation system inspired by Tim Sweeney/Epic Megagames' classic shareware game ZZT. MegaZeux was created in late 1994 by Gregory Janson, who formed his own company, Software Visions...
, versions of Game Editor
Game Editor
Game Editor is a 2D game authoring package. It supports multi platform development to iPhone, iPad, Mac OS X, Windows , Linux, Windows-based Smartphones, GP2X, Pocket PCs, and Handheld PCs...
, the Game Maker
Game Maker
GameMaker is a Windows and Mac IDE originally developed by Mark Overmars in the Delphi programming language. It is currently developed and published by YoYo Games, a software company in which Overmars is involved...
inspired G-Creator, and ZGameEditor
ZGameEditor
ZGameEditor, also referred to as ZGE, is a game development system written by Ville Krumlinde in the Free Pascal programming language and CodeGear Delphi. The first public version was released on Feb 1, 2007...
.
Rise in popularity and diversity
Pingus (video game)
Pingus is a free, open source computer game inspired by Lemmings and created by Ingo Ruhnke. It features penguins instead of lemmings. It has been reviewed favorably by CNN.com, about.com, Unix Review, and other publications.-History:...
(Lemmings
Lemmings (video game)
Lemmings is a puzzle computer game developed by DMA Design and published by Psygnosis in . Originally developed for PC and Commodore Amiga, Lemmings was one of the most popular computer games of its time, and several gaming magazines gave it some of their highest review scores at the time...
clone), SuperTux
SuperTux
SuperTux is a free, open-source two-dimensional platform game. The game was originally created by Bill Kendrick and is maintained by the SuperTux Development Team....
and Secret Maryo Chronicles
Secret Maryo Chronicles
Secret Maryo Chronicles is a free, open source two-dimensional platform game. It was developed and is maintained by the Secret Maryo Chronicles development team, led by Florian Richter ....
(Super Mario Bros-inspired), WarMUX and Hedgewars
Hedgewars
Hedgewars is a turn-based free and open-source strategy game, artillery game, skill game. It is cross-platform and runs on FreeBSD, Linux, Mac OS X, Microsoft Windows, iOS, and Android. It features a single-player mission/tutorial mode, in addition to multi-team multiplayer gameplay...
(Worms) as well as Frets on Fire
Frets on Fire
Frets on Fire is a free, open-source Finnish music video game created by Unreal Voodoo. Players use the keyboard to play along with markers which appear on screen, with the aim to score points, achieve a high point multiplier, and complete a song...
, which is a recreation of Guitar Hero
Guitar Hero
Guitar Hero is a music video game developed by Harmonix Music Systems and published by RedOctane for the PlayStation 2 video game console. It is the first entry in the Guitar Hero series. Guitar Hero was released on November 8, 2005 in North America, April 7, 2006 in Europe and June 15, 2006 in...
. A number of these games and those mentioned earlier and later in this section have even received mainstream press coverage and have helped to establish free gaming as a moderately popular past time, even if mostly enjoyed by Linux
Linux
Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
and BSD users. Frozen Bubble
Frozen Bubble
Frozen Bubble is a free software Puzzle Bobble style computer game which is available on several operating systems including Linux, Windows, Mac OS X, the Symbian Series 60, Windows Phone 7 and Android line of smartphones...
, originally a clone of Puzzle Bobble
Puzzle Bobble
, also known as Bust-a-Move, is a 1994 arcade puzzle game created by Taito Corporation, based on Taito's popular 1986 arcade game Bubble Bobble, featuring characters and themes from the original...
, has become a classic known for its addictive gameplay and winner of many Linux Journal
Linux Journal
Linux Journal is a monthly technology magazine published by Belltown Media, Inc. of Houston, Texas. The magazine focuses specifically on Linux, allowing the content to be a highly specialized source of information for open source enthusiasts.-History:...
reader's choice awards. These games and others have also helped expand the prevalent Tux genre which started with titles and like A Quest for Herring and are related to the activist content of games like XBill. More unique games like Neverball
Neverball
Neverball is a 3D platform game similar to Super Monkey Ball. It is currently available for Windows platforms, Mac OS X, Linux, FreeBSD, Dreamcast, AmigaOS 4, iOS and Maemo...
, another 3D title, have also been able to carve out their own niches.
Strategy games have also been a prevalent force in free software gaming, partly due to the lack of proprietary strategy games for free software operating systems as compared to other genres like first-person shooters and role playing games. FreeCiv began the trend, and was followed by other clone titles like FreeCol
FreeCol
FreeCol is a 4X video game, a clone of Sid Meier's Colonization. Released under the GNU General Public License, FreeCol is free and open source software.FreeCol is mostly programmed in Java and should thus be platform-independent...
, LinCity
Lincity
Lincity is a free construction and management simulation game, which puts the player in control of managing a city's socio-economy. Its name is a play on the title of the original city-building game, SimCity, and it was released under the GNU General Public License.- Gameplay :Lincity is a city and...
and Widelands
Widelands
Widelands is a free slow-paced real-time strategy video game under the GNU General Public License. Widelands takes many ideas from and is quite similar to The Settlers and The Settlers II. It is still a work in progress game, with development still required in graphics and bugfixing...
. The Stratagus
Stratagus
Stratagus was a free cross-platform real-time strategy game engine used to build other games. It is written in C with the configuration language being Lua. SDL, gzip and bzip2 are among the external libraries used.-History:...
project began as an attempt to recreate the proprietary Warcraft II engine, under the name FreeCraft. Blizzard Entertainment
Blizzard Entertainment
Blizzard Entertainment, Inc. is an American video game developer and publisher founded on February 8, 1991 under the name Silicon & Synapse by three graduates of UCLA, Michael Morhaime, Allen Adham and Frank Pearce and currently owned by French company Activision Blizzard...
sent a cease and desist letter in 2003 over the use of the name "craft" in comparison to Warcraft
Warcraft
Warcraft: Orcs & Humans is a real-time strategy game , developed by Blizzard Entertainment and published by Blizzard and Interplay Entertainment. The MS-DOS version was released in November 1994 and the Macintosh version in late 1996. Sales were fairly high, reviewers were mostly impressed, and the...
and StarCraft
StarCraft
StarCraft is a military science fiction real-time strategy video game developed by Blizzard Entertainment. The first game of the StarCraft series was released for Microsoft Windows on 31 March 1998. With more than 11 million copies sold worldwide as of February 2009, it is one of the best-selling...
. Though the earlier free software strategy game CRAFT: The Vicious Vikings shared the name "craft" without controversy.
With the new, legally inoffensive name Stratagus, the team began work on a new strategy game called Bos Wars
Bos Wars
Bos Wars is an open source, cross-platform real-time strategy video game. The project was started by Tina Petersen in 2004, and the current project leader is François Beerten...
. Development on this game still continues, as well as the modern Warcraft II port Wargus. Other games branched out of the engine project as well such as the Battle for Mandicor and Astroseries projects and the StarCraft port attempt Stargus. After the Stratagus example, other real time strategy games were developed, such as Globulation 2
Globulation 2
Globulation 2 is a real-time strategy game is available in beta as of January 2009 and a final version is due to be released in the future. The game minimizes gaming micromanagement by automatically assigning tasks to units.-Game modes:...
, which experiments with game management mechanics, 0 A.D.
0 A.D. (game)
0 A.D. is a free, open-source, cross-platform real-time strategy game under development by Wildfire Games. It is a historical war and economy game focusing on the years between 500 B.C. and A.D. 500...
, a former freeware project, and the 3D projects Spring and Glest
Glest
Glest is a free and open source real-time strategy computer game developed by a team based in Spain.-Development:Release of version 3.0 added online multiplayer LAN/Internet support. Glest is designed to be moddable, with game elements defined by editable XML files, and includes a map editor.Since...
. In addition, the more economically driven strategy game Widelands
Widelands
Widelands is a free slow-paced real-time strategy video game under the GNU General Public License. Widelands takes many ideas from and is quite similar to The Settlers and The Settlers II. It is still a work in progress game, with development still required in graphics and bugfixing...
bases itself upon the proprietary Settlers
The Settlers
The Settlers is a slow-paced simulation computer game by German developer Blue Byte Software, first released in 1993 for Commodore Amiga and in 1994 for the PC...
franchise.