Developer(s) | Valve |
---|---|
Initial release | October 2004 |
Written in | C++ |
Middleware | Havok |
Predecessor | GoldSrc |
Successor | Source 2 |
License | Proprietary |
Source is a 3D game engine developed by Valve. It debuted as the successor to GoldSrc in 2004 with the releases of Half-Life: Source , Counter-Strike: Source , and Half-Life 2 . It is most well-known for its usage by Valve, but the engine has been used both by small teams and individuals to create modifications of Valve games, [1] and other studios creating distinct games, notably Troika Games' title Vampire: The Masquerade – Bloodlines . Valve continued to create incremental updates to the Source engine after its 2004 release, most of which coincided with games created by Valve. In the late 2010s, Valve created the Source 2 engine to replace Source, with it publicly debuting alongside Half-Life: Alyx . The Source engine is most well-known for its advancements in physics, AI, and graphics. [2]
Source distantly originates from the GoldSrc engine, itself a heavily modified version of John Carmack's Quake engine with some code from the Quake II engine. Carmack commented on his blog in 2004 that "there are still bits of early Quake code in Half-Life 2". [3] Valve employee Erik Johnson explained the engine's nomenclature on the Valve Developer Community: [4]
When we were getting very close to releasing Half-Life (less than a week or so), we found there were already some projects that we needed to start working on, but we couldn't risk checking in code to the shipping version of the game. At that point we forked off the code in VSS to be both
/$Goldsrc
and/$Src
. Over the next few years, we used these terms internally as "Goldsource" and "Source". At least initially, the Goldsrc branch of code referred to the codebase that was currently released, and Src referred to the next set of more risky technology that we were working on. When it came down to show Half-Life 2 for the first time at E3, it was part of our internal communication to refer to the "Source" engine vs. the "Goldsource" engine, and the name stuck.
Source was developed part-by-part from this fork onwards, slowly replacing GoldSrc in Valve's internal projects [5] and, in part, explaining the reasons behind its unusually modular nature. Valve's development of Source since has been a mixture of licensed middleware and in-house-developed code. Older versions of Source use Bink Video for video playback, [6] however more recent releases of the Source engine use WebM videos for menu backgrounds, Full Motion Videos, and splash screens. [7] .
Source was created to evolve incrementally with new technology, as opposed to the backward compatibility-breaking "version jumps" of its competitors. Different systems within Source are represented by separate modules which can be updated independently. With Steam, Valve can distribute these updates automatically among its many users. In practice, however, there have been occasional breaks in this chain of compatibility. The release of Half-Life 2: Episode One and The Orange Box both introduced new versions of the engine that could not be used to run older games or mods without the developers performing upgrades to code and, in some cases, content. [8] Both cases required markedly less work to update its version than competing engines.
The Source 2006 branch was the term used for Valve's games using technology that culminated with the release of Half-Life 2: Episode One. HDR rendering and color correction were first implemented in 2005 using Day of Defeat: Source , which required the engine's shaders to be rewritten. [9] The former, along with developer commentary tracks, were showcased in Half-Life 2: Lost Coast . Episode One introduced Phong shading and other smaller features. Image-based rendering technology had been in development for Half-Life 2 , [10] but was cut from the engine before its release. It was mentioned again by Gabe Newell in 2006 as a piece of technology he would like to add to Source to implement support for much larger scenes that are impossible with strictly polygonal objects. [11]
The Source 2007 branch represented a full upgrade of the Source engine for the release of The Orange Box. An artist-driven, threaded particle system replaced previously hard-coded effects for all of the games within.[ citation needed ] An in-process tools framework was created to support it, which also supported the initial builds of Source Filmmaker. In addition, the facial animation system was made hardware-accelerated on modern video cards for "feature film and broadcast television" quality. [12] The release of The Orange Box on multiple platforms allowed for a large code refactoring, which let the Source engine take advantage of multiple CPU cores. [13] However, support on the PC was experimental and unstable [14] until the release of Left 4 Dead. [15] Multiprocessor support was later backported to Team Fortress 2 and Day of Defeat: Source . [16] Valve created the Xbox 360 release of The Orange Box in-house, and support for the console is fully integrated into the main engine codeline. It includes asset converters, cross-platform play and Xbox Live integration. [17] Program code can be ported from PC to Xbox 360 simply by recompiling it. [18] The PlayStation 3 release was outsourced to Electronic Arts, and was plagued with issues throughout the process. Gabe Newell cited these issues when criticizing the console during the release of The Orange Box. [19]
The Left 4 Dead branch is an overhaul of many aspects of the Source engine through the development of the Left 4 Dead series. Multiprocessor support was further expanded, allowing for features like split screen multiplayer, additional post-processing effects, event scripting with Squirrel, and the highly-dynamic AI Director. The menu interface was re-implemented with a new layout designed to be more console-oriented. This branch later fueled the releases of Alien Swarm and Portal 2 , the former released with source code outlining many of the changes made since the branch began. Portal 2, in addition, served as the result of Valve taking the problem of porting to PlayStation 3 in-house, and in combination with Steamworks integration creating what they called "the best console version of the game". [20]
In April 2010, Valve released all of their major Source games on OS X, coinciding with the release of the Steam client on the same platform. Valve announced that all their future games would be released simultaneously for Windows and Mac. [21] [22] The first of Valve's games to support Linux was Team Fortress 2 , the port released in October 2012 along with the closed beta of the Linux version of Steam. Both the OS X and Linux ports of the engine take advantage of OpenGL and are powered by Simple DirectMedia Layer. [23] During the process of porting, Valve rearranged most of the games released up to The Orange Box into separate, but parallel "singleplayer" and "multiplayer" branches. The game code to these branches was made public to mod developers in 2013, and they serve as the current stable release of Source designated for mods. Support for Valve's internal Steam Pipe distribution system as well as the Oculus Rift are included. [24] In May 2014, Nvidia released ports of Portal and Half-Life 2 to their Tegra 4-based Android handheld game console Nvidia Shield. [25]
Source 2 was announced by Valve as the successor to Source at the Game Developers Conference in March 2015. [26] There, Valve stated that it would be free to use for developers, with support for the Vulkan graphical API, as well as using a new in-house physics engine called Rubikon. [27] [28] In June 2015, Valve announced that Dota 2 , originally made in the Source engine, would be ported over to Source 2 in an update called Dota 2 Reborn . [29] [30] Reborn was first released to the public as an opt-in beta update that same month before officially replacing the original client in September 2015, making it the first game to use the engine. [31] [32] The engine had succeeded Source by the late 2010s.
Source SDK is the software development kit for the Source engine, and contains many of the tools used by Valve to develop assets for their games. It comes with several command-line programs designed for special functions within the asset pipeline, as well as a few GUI-based programs designed for handling more complex functions. Source SDK was launched as a free standalone toolset through Steam, and required a Source game to be purchased on the same account. Since the release of Left 4 Dead in late 2008, Valve began releasing "Authoring Tools" for individual games, which constitute the same programs adapted for each game's engine build. After Team Fortress 2 became free-to-play, Source SDK was effectively made open to all Steam users. When some Source games were updated to Source 2013, the older Source SDKs were phased out. The three applications mentioned below are now included in the install of each game.[ citation needed ]
There are three applications packaged in the Source SDK: Hammer Editor, Model Viewer, and Face Poser. The Model Viewer is a program that allows users to view models and can be used for a variety of different purposes, including development. Developers may use the program to view models and their corresponding animations, attachment points, bones, and so on. Face Poser is the tool used to access facial animations and choreography systems. This tool allows one to edit facial expressions, gestures and movements for characters, lip sync speech, and sequence expressions and other acting cues and preview what the scene will look like in the game engine. [33]
The Hammer Editor, the engine's official level editor, uses rendering and compiling tools included in the SDK to create maps using the binary space partitioning (BSP) method. Level geometry is created with 3D polygons called brushes; each face can be assigned a texture which also defines the properties of the surface such as the sounds used for footsteps. [34] Faces can also be converted into a displacement allowing for more natural shapes such as hills to be created.
Scenery objects or complex geometry can be imported as separate 3D models from the game directory. These models can also be used as physics objects or interactive props. The editor also features an in-depth logic I/O system that can be used to create complex interactive elements. Signals to trigger different responses or change the state of an entity can be sent between entities such as buttons, NPCs, intangible trigger brushes, and map props.
The Source Dedicated Server (SRCDS) is a standalone launcher for the Source engine that runs multiplayer game sessions without requiring a client. It can be launched through Windows or Linux and can allow for custom levels and assets. Most third-party servers additionally run Metamod:Source and SourceMod, which together provide a framework on top of SRCDS for custom modification of gameplay on existing titles. [35] [36]
Source Filmmaker (SFM) is a 3D animation application that was built from within the Source engine. [37] Developed by Valve, the tool was originally used to create movies for Day of Defeat: Source and Team Fortress 2. It was also used to create some trailers for Source Engine games. SFM was released to the public in 2012.
In June 2016, Valve released the Destinations Workshop Tools, a set of free virtual reality (VR) creation tools running using the Source 2 SDK. [38]
In June 2005, Valve opened the Valve Developer Community wiki. It replaced Valve's static Source SDK documentation with a full MediaWiki-powered community site. [39]
Valve staff have occasionally produced professional and/or academic papers for various events and publications, including SIGGRAPH, Game Developer Magazine and Game Developers Conference, explaining various aspects of Source engine's development. [40]
Titanfall , Titanfall 2 , and Apex Legends are not included because their engines, while originally based on the Source SDK, were modified to the point that they are effectively different engines. [44]
Counter-Strike is a tactical first-person shooter game developed by Valve. It was initially developed and released as a Half-Life modification by Minh "Gooseman" Le and Jess Cliffe in 1999, before Le and Cliffe were hired and the game's intellectual property acquired. Counter-Strike was released by Valve for Microsoft Windows in November 2000, and is the first installment in the Counter-Strike series. Several remakes and ports were released on Xbox, as well as OS X and Linux.
Half-Life is a 1998 first-person shooter (FPS) game developed by Valve Corporation and published by Sierra Studios for Windows. It was Valve's debut product and the first game in the Half-Life series. The player assumes the role of Gordon Freeman, a scientist who must escape from the Black Mesa Research Facility after it is invaded by aliens following a disastrous scientific experiment. The gameplay consists of combat, exploration and puzzles.
Valve Corporation, also known as Valve Software, is an American video game developer, publisher, and digital distribution company headquartered in Bellevue, Washington. It is the developer of the software distribution platform Steam and the game franchises Half-Life, Counter-Strike, Portal, Day of Defeat, Team Fortress, Left 4 Dead, and Dota.
Video game modding is the process of alteration by players or fans of one or more aspects of a video game, such as how it looks or behaves, and is a sub-discipline of general modding. Mods may range from small changes and tweaks to complete overhauls, and can extend the replay value and interest of the game.
Half-Life 2 is a 2004 first-person shooter (FPS) game developed and published by Valve Corporation. It was published for Windows on Valve's digital distribution service, Steam. Like the original Half-Life (1998), Half-Life 2 combines shooting, puzzles, and storytelling, and adds new features such as vehicles and physics-based gameplay. The player controls Gordon Freeman, who joins a resistance to liberate Earth from the Combine, an interplanetary alien empire.
Steam is a video game digital distribution service and storefront developed by Valve Corporation. It was launched as a software client in September 2003 to provide game updates automatically for Valve's games, and expanded to distributing third-party titles in late 2005. Steam offers various features, like game server matchmaking with Valve Anti-Cheat measures, social networking, and game streaming services. Steam client's functions include game update automation, cloud storage for game progress, and community features such as direct messaging, in-game overlay functions and a virtual collectable marketplace.
Valve Anti-Cheat (VAC) is an anti-cheat tool developed by Valve as a component of the Steam platform, first released with Counter-Strike in 2002.
Sven Co-op is a co-op variation of the 1998 first-person shooter Half-Life. The game, initially released as a mod in January 1999, and created by Daniel "Sven Viking" Fearon, enables players to play together on online servers to complete levels, many of which are based on the Half-Life universe but include other genres. In addition to the cooperative gameplay, Sven Co-op includes improvements from the original Half-Life, including improved artificial intelligence for both enemy and allied non-player characters.
Black Mesa is a 2020 first-person shooter game developed and published by Crowbar Collective. It is a third-party remake of Half-Life (1998) made in the Source game engine. Originally published as a free mod in September 2012, Black Mesa was approved for commercial release by Valve, the developers of Half-Life. The first commercial version was published as an early-access release in May 2015, followed by a full release in March 2020 for Linux and Windows.
Alien Swarm is a multiplayer top-down shooter video game developed by Valve. It is a remake of a mod for Unreal Tournament 2004, and it was developed by the original team, who were hired by Valve during the course of the development process.
Dota 2 is a 2013 multiplayer online battle arena (MOBA) video game by Valve. The game is a sequel to Defense of the Ancients (DotA), a community-created mod for Blizzard Entertainment's Warcraft III: Reign of Chaos. Dota 2 is played in matches between two teams of five players, with each team occupying and defending their own separate base on the map. Each of the ten players independently controls a powerful character known as a "hero" that all have unique abilities and differing styles of play. During a match players collect experience points and items for their heroes to defeat the opposing team's heroes in player versus player combat. A team wins by being the first to destroy the other team's "Ancient", a large structure located within their base.
GoldSrc, sometimes called the Half-LifeEngine, is a proprietary game engine developed by Valve. At its core, GoldSrc is a heavily modified version of id Software's Quake engine. It made its debut in 1998 with Half-Life and powered future games developed by or with oversight from Valve, including Half-Life's expansions, Day of Defeat and games in the Counter-Strike series.
Source Filmmaker is a 3D computer graphics software tool published by Valve for creating animated films, which uses the Source game engine. Source Filmmaker has been used to create many community-based animated shorts for various Source games, such as Team Fortress 2, the Left 4 Dead series, and Half-Life 2.
SteamOS is a Linux distribution developed by Valve. It incorporates Valve's popular namesake Steam video game storefront and is the primary operating system for the Steam Deck, Valve's portable gaming device, as well as Valve's earlier Steam Machines. SteamOS is open source with some closed source components.
Source 2 is a video game engine developed by Valve. The engine was announced in 2015 as the successor to the original Source engine, with the first game to use it, Dota 2, being ported from Source that same year. Other Valve games, such as Artifact, Dota Underlords, Half-Life: Alyx, and Counter-Strike 2, have been produced with the engine.
Based on Id Software's open stance towards game modifications, their Quake series became a popular subject for player mods beginning with Quake in 1996. Spurred by user-created hacked content on their previous games and the company's desire to encourage the hacker ethic, Id included dedicated modification tools into Quake, including the QuakeC programming language and a level editor. As a game that popularized online first-person shooter multiplayer, early games were team- and strategy-based and led to prominent mods like Team Fortress, whose developers were later hired by Valve to create a dedicated version for the company. Id's openness and modding tools led to a "Quake movie" community, which altered gameplay data to add camera angles in post-production, a practice that became known as machinima.
Dota is a series of strategy video games. The series began in 2003 with the release of Defense of the Ancients (DotA), a fan-developed multiplayer online battle arena (MOBA) mod for the video game Warcraft III: Reign of Chaos and its expansion, The Frozen Throne. The original mod features gameplay centered around two teams of up to five players who assume control of individual characters called "heroes", which must coordinate to destroy the enemy's central base structure called an "Ancient", to win the game. Ownership and development of DotA were passed on multiple times since its initial release until Valve hired the mod's lead designer IceFrog and after an ongoing legal dispute with Blizzard Entertainment, the developer of Warcraft III, brokered a deal that allowed for Valve to inherit the trademark to the Dota name.
Chris Green: The Source engine supports a wide variety of shaders. The refraction shader on the window here requires us to copy the scene to a texture, refract it, and then apply it the window surface. To fully support HDR, every shader in the engine needed to be updated, so this refraction shader was improved to the support the full range of contrast.