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Source

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id Tech 2 id Tech 2GoldSrc GoldSrcSource SourceSource 2 Source 2

This article is about the game engine. For the documentation on Source and its SDK, see Source SDK Documentation.
Source
Logo of the Source engine.
Screenshot in-game of Counter-Strike: Source, using the Source Engine.
Screenshot in-game of Counter-Strike: Source, using the Source Engine.
Developer(s)
Release date(s)
October 7, 2004
Platform(s)
Windows, macOS, Linux, Xbox, Xbox 360, PlayStation 3, Nintendo Switch, Android
Note: Valve (first-party) games only.
Written in
License
Proprietary
(Source 2013, Alien Swarm engine branch source code available for non-commercial purposes.)
Official website
Official Website (archived)
Links
GitHub Issues GitHub Issues (bug report for all Source games, except CS:GO)
Source SDK 2013 source code Source SDK 2013 source code
Predecessor
Successor
Screenshot in-game of Counter-Strike: Global Offensive, using Valve's latest branch of the Source Engine.
Promotional screenshot of Apex Legends, which runs on a heavily modified version of the Source Engine, featuring DirectX (Direct3D) 11, detailed models and better graphics, plus increased the engine limit, allowing maps to be larger.

Source Source is a 3D game engine created by Valve in 2004, and is the successor to GoldSrc. The Source engine is well-known for its advancements in physics, AI, and graphics which made the games realistic for its time, while being scalable on older, less powerful hardware. One game, Half-Life 2, earned several awards for it's graphics, which were made possible with Source. Source has been used by Valve, third-party companies, and (much like GoldSrc) countless community mods by people around the globe, with at least 100 games developed on Source. The engine also has several branches, each with new features added and improved graphical capabilities.

Despite the Source engine being 20 years old, and has been superseded by the Source 2 engine for first-party usage since 2015, it's still being commonly used today by modders and some third-party companies due to the lack of some Source 2 documentation and was rarely licensed to third-party developers compared to Source, and it's still regularly being maintained with engine and security updates.

Clarify: not all Source games have Valve Anti-Cheat. See Apex Legends.

Features

List of Source Source engine features and capabilities. Some new features listed here may not apply to previous or later Source branches, or third-party games/branch.

For a list of Source branches (including third-party games) with their specific new features, see this category page.

Renderer

  • Supports Shader Model 2.0 to 3.0
  • Anti-aliasing support (MSAA, FXAA, MLAA, TAA, etc.)
    • See the Anti-aliasing page for more information, and features & drawbacks with various anti-aliasing methods.
  • More anisotropic and texture filtering options
    • Anisotropic filtering allow textures on far distance to look sharper and less blurry.
    • Compared to GoldSrc (prior to 2013) featuring only Bilinear or Trilinear texture filtering, Source features more texture filtering options, ranging from Bilinear, Trilinear, Anisotropic 2x up to 16x.
  • Support for both forward and deferred rendering pipelines.
    • Deferred rendering is a rendering technique that allow games to render as much lights with little performance impact. Deferred rendering are commonly used in most modern titles.
  • Bump mapping and Normal mapping on models and the world
  • Author shaders with HLSL
  • Cube and environment mapping
    • Cubemapping also supports Anisotropy (in all games since Counter-Strike: Global Offensive)
  • Phong shading for models
    • Phong is also supported on world brushes (in all games since Counter-Strike: Global Offensive)(also in Mapbase)
  • Dynamic lights, vertex lighting and lightmaps, many light types including flickering, pulsing etc.
  • HDR (in all games since Source 2006) and LDR (SDR) lighting
  • Water with refraction, real-time world reflections and fresnel effects
  • Advanced particle systems that can emit sprites or models
  • Render-to-texture shadows allow for a large number of characters per scene (in all games since Left 4 Dead engine branch) (also in MapbaseXengineDark Messiah of Might and Magic)
  • Occluder entities for visibility blocking
  • Indoor/Outdoor environments
    • Deformable terrain
    • 3D Skyboxes extend the horizon and add parallax on distant objects
    • Dynamically rendered organics (grass, trees, etc.)
    • Swaying trees (in all games since Left 4 Dead engine branch) (also in Team Fortress 2XengineGarry's ModMapbase)
  • Subdivision surfaces, diffuse & specular bump maps
  • Real-time radiosity lighting
  • Real-time Cascaded Shadow Mapping that comes from the skybox (in all games since Counter-Strike: Global Offensive) (also in Alien Swarm DeferredLambda WarsXengine)
  • Effects include but are not limited to: particles, beams, volumetric smoke, sparks, blood, & environmental effects like fog and rain
  • Scalability
  • Screen Space Ambient Occlusion (SSAO) (only in Source Filmmaker Dota 2)
    • A technique for efficiently approximating the ambient occlusion effect in real time.
  • Widescreen display support
    • Source is one of the earliest game engines to support Widescreen monitors natively (16:9 and 16:10 aspect ratio) without stretching the image, while most games from that era are usually designed for 4:3/5:4 displays only.
      Games such as Half-Life 2 support widescreen display at launch back in 2004, with horizontal FOV (field of view), allow you to see more details.
  • Physically Based Rendering (only in Strata SourceTitanfall engine branchRTX RemixHunt Down the FreemanPortal 2: Desolation)
  • Parallax Occlusion Mapping(only in XengineStrata Source)
  • Support various graphics API (Direct3D, OpenGL, Vulkan)
  • Direct3D versions
    • Direct3D 9
      • DirectX compatibility levels for older graphics cards:
      • DirectX 7.0 (Source 2004/2006 or RTX Remix games only)
      • DirectX 8.0 (dxlevel 80 fixed-function shaders)
      • DirectX 8.1 (dxlevel 81 same as above, with smooth shadows)
      • DirectX 9.0 (dxlevel 90)
      • DirectX 9.0+ (dxlevel 95)
      • Note.pngNote:DirectX compatibility levels are no longer supported since Left 4 Dead engine branch.
        Also, regardless which dxlevel was set to, all Source games will always run on Direct3D 9.
    • Direct3D 9Ex (in all games since Source 2013) (also in Counter-Strike: Global Offensive) - DX9 Windows Aero extensions, requires Vista or later. User can enable/disable in Video Settings - Advanced (Windows Aero extensions), or through -disable_d3d9ex (only in Counter-Strike: Global Offensive).
    • Direct3D 11 (only in Titanfall engine branchStrata SourceVindictus)
    • Direct3D 12 (only in Apex Legends)
    • Note.pngNote:Direct3D 9 can be forced by the launch option -dx9, if it was forced by commands such as -gamepadui, which enables both the Gamepad UI and Vulkan renderer unless combined with -dx9
  • OpenGL(in all games since Source 2009/Source Multiplayer) which is another graphics API used in Source games on macOS and Linux.
    • dxlevel 92 is the OpenGL equivalent to DirectX 9 Shader Model 3 (D3D9.0c)
  • Vulkan graphics API (only in Half-Life 2PortalRTX RemixLeft 4 Dead 2Portal 2Counter-Strike: Global Offensive)
    • A successor to OpenGL, Vulkan can be used to workaround various graphical issues such as the Portal 2's projected textures, which does not render properly on newer graphics drivers (both NVIDIA and AMD). Enable Vulkan using -vulkan launch options.
Note.pngNote:Counter-Strike: Global Offensive Counter-Strike: Global Offensive has Vulkan support only on Linux
Note.pngNote:Source allows up to 8 LOD Models, although it does not have automatic level of detail out of box. Manual LoD is supported, however.
Warning.pngWarning:Counter-Strike: Global Offensive Counter-Strike: Global Offensive currently does not support level of detail. $lod will be ignored, but the model will still work. Try to avoid using this command in Counter-Strike: Global Offensive.

Materials System

  • Instead of traditional textures, Source defines sets of materials that specify what the object is made from and the texture used for that object. A material specifies how an object will fracture when broken, what it will sound like when broken or dragged across another surface, and what that object's mass and buoyancy are. This system is much more flexible than other texture-only systems
  • Materials can interact with objects or NPCs, such as mud or ice for vehicles to slide/lose traction on

Multiplayer Network Code

  • Time- and gamer-tested by millions of gamers around the world
  • Support for both LAN-based multiplayer and Internet-based multiplayer games
  • Prediction analysis for interpolating collision/hit detection
  • Optimizations for high-latency, high-packet-loss 56k connections

Advanced Characters

  • Detailed and believable characters
  • Realistic eyes
    • Focus on player/object, not simply parallel views
    • Proper eye bulge for realistic eye reflections
  • Simulated musculature provides outstanding emotions, speech, and body language
  • Language independent speech, characters can speak naturally in many languages
  • Skeletal/bone system for animation
  • Layered animation system can synthesize complex animations out of several pieces

Physics

  • Uses Havok physics engine, licensed from Havok Group (now acquired by Microsoft)
  • More responsive world with realistic interactions
  • Sounds & graphics follow from physics
  • AI characters can interact with physically simulated objects
  • Ropes/cables, machines, constraint systems, ragdoll physics
  • Can be controlled by level design
  • Kinematic animated bone followers
  • Custom procedural physics controllers
  • Vehicles
    • Wheels slip and skid
    • Realistic suspensions with springs on each wheel
    • Realistic leaning during acceleration/deceleration and turning
    • Individually tunable parameters such as horsepower, gearing, max speed, shift speed, tire material, tire friction, spring tension/dampening, etc.
    • Multiple players in a vehicle in multiplayer
    • Hovercraft support for cheaper simulation

Advanced AI

  • I/O system allows level designers to control AI
  • Sophisticated navigation: characters that run, fly, jump, crouch, climb stairs and ladders, and burrow underground
  • AI senses things using sight, sound, and smell
  • AI relationships determine friend/foe status of other entities
  • Battle AI allows squads of AI characters to operate together, know when to advance, retreat, lay cover fire, etc.

Sound System

  • 7.1, 5.1 surround sound, 4 speaker surround
Icon-Bug.pngBug:Despite all Source games prior to Alien Swarm has 7.1 audio option, the game only outputs only 5.1 surround despite 7.1 selected. This issue is not affected by some third-party games, such as Titanfall 2, Apex Legends as they used newer version of Miles Sound System, which have this problem fixed.  [todo tested in?]
Note.pngNote:Some or newer Source games (such as Alien Swarm, Portal 2 and Counter-Strike: Global Offensive) may not include options to enable 7.1 surround sound without using console commands, despite this, 7.1 audio option are most likely still broken in those games.
  • High-quality 3D spatialization
  • Custom software DSP
  • Automatic DSP based on environmental geometry
  • Microsoft ADPCM-compressed WAV files
  • 16-bit 44.1 KHz (CD Quality), stereo wave data with all features
Note.pngNote:Source does not support 48 KHz audio (DVD Quality) by default.
  • MP3 decompression (requires Miles license)
  • Support for audio streaming on any wave [Clarify]
  • Real-time wave file stitching [Clarify]
  • Pre-authored Doppler effect encoded waves
  • Pre-authored distance variant encoded waves
  • Commentary system

UI

Screenshot of Half-Life 2: Episode Two main menu, which is rendered using VGUI, with New Game, Options, and Achievements window opened.
Screenshot of VGUI's Gamepad UI used in some Source 2013 games after 2022. This UI was enabled by default when playing on Steam Deck.
  • Server browser — Displays all active game servers and allows a player to choose which one to participate in. Players can filter and sort server lists to speed up the display and selection of a server.
  • VGUI — Valve's custom GUI interface mimics most of the Windows controls but is rendered using the Source engine for both in game and out of game uniform UI display. Some features:
    • Dynamic in-game HUD display
    • Many widgets/controls (e.g., buttons, treeview, html control…)
    • Themes/custom visualization allowed
    • Platform independent
    • Localized text (Unicode compliant)
    • Gamepad UI (Source 2013 Source 2013 version) — Since the release of Half-Life 2 (and its episodes) as well as Portal updates in 2022, Valve have added a modern UI which is designed for consoles and handhelds like Steam Deck Steam Deck. With the new Gamepad UI, it was more scalable across any resolution (including 4K and higher), unlike the regular VGUI (which, the higher the resolution, the text and UI will become smaller). This UI can be also enabled manually by using -gamepadui command line argument (which will also enable Vulkan renderer that may not work on some older GPUs unless -dx9 is used in combination of -gamepadui).
  • Scaleform (officially called Scaleform GFx) — Introduced with CS:GO engine branch at launch until 2018, this is a vector graphics rendering engine used to display Adobe Flash-based UI and HUD for games.
  • Panorama (in all games since Counter-Strike: Global Offensive) — Introduced in 2018, replacing Scaleform, Valve's new Custom GUI interface that resembles modern web design and authoring (HTML5/CSS/JS). Using .XML and JavaScript files, developers can create dynamic and clean HUDs and menus and even high-quality in-game intractable panels.

Programming

  • Source natively support various CPU architectures, such as x86 (PC and 8th, 9th-gen Consoles), ARM (Android Android, Nintendo Switch Nintendo Switch), PowerPC (Xbox 360 Xbox 360, PlayStation 3 PlayStation 3), and more, with both 32 and 64-bit.
    • Support for 64-bit architecture will allow Source to handle more than 2-4GB of RAM limit.
    • Historically, Half-Life 2 had a 64-bit update in 2005, but it was later removed for unknown reasons. CS:GO later received an 64-bit update in 2016 for Mac and Linux systems. On April 19, 2024, Team Fortress 2 was upgraded to 64-bit on Windows and Linux.
  • All code written in C/C++ using Visual Studio .NET 2003 and later. Easily and quickly derive new entities from existing base classes
  • Internal context sensitive performance monitoring system
  • Graphics performance measurement tools built into the engine
  • Modular code design (via DLLs) allows swapping out of core components for easy upgrading or code replacement
  • VScript scripting system allows using external coding languages, such as Squirrel and Lua, in maps to create more complex systems (in all games since Left 4 Dead 2) (also in Team Fortress 2Mapbase)

Tools

Screenshot of one of the Source SDK tools, Valve Hammer Editor, a WYSIWYG map editor.

Branches

The Source engine has multiple branches, each of them adds new features and changes. The latest version is Source 2013, which has two sub-branches: Singleplayer and Multiplayer, the Multiplayer branch has additional features not available on Singleplayer sub-branch. Games such as Left 4 Dead to Counter-Strike: Global Offensive also introduces many newer features and graphical improvements. Both Source 2013 and Alien Swarm engine branch engine code are publicly available.

Some third-party games may also have their own engine branches, with many new features that are not available with any official Source branch.

Products using Source ViewDiscussEdit templatePurge

This is the list of games that uses the Source Source engine.

Products made by Valve

Click here to edit this list.
Release date Title Co-developed with Engine branch Platforms Notes
7 Oct 2004 Counter-Strike: Source Counter-Strike: Source Turtle Rock Studios
Hidden Path Entertainment (2010 update)
Source 2004 Source 2004 (launch)
Source 2013 Multiplayer Source 2013 Multiplayer (currently)
PC: Windows, Mac, Linux First game to use the Source engine. Remake of Counter-Strike. Hidden Path Entertainment alongside Valve worked on the May 7, 2010 update, which upgraded the game's engine from Source 2006 to 2009, and added 144 (now 146) achievements, a new domination and revenge system similar to Team Fortress 2, player stats and more.
Hidden Path Entertainment also worked on the unreleased Xbox 360 port of CS:S, which would later become Counter-Strike: Global Offensive Counter-Strike: Global Offensive after Valve saw the opportunity during it's development to turn the port into a new game. Mac version of the game was later release in June 2010, and Linux in 2013.
16 Nov 2004 Half-Life: Source Half-Life: Source Source 2004 Source 2004 (launch)
Source 2013 Singleplayer Source 2013 Singleplayer (currently)
PC: Windows, Mac, Linux Remaster of Half-Life. It is critically panned by most gamers since 2013 due to the huge amount of bugs that were introduced when the game was updated to Source 2013 Source 2013. Prior to the 2013 update, it was generally positively received by critics and most gamers, but some are disappointed over the game graphics (especially the textures) that are largely unchanged, while also having a realistic 3D Skybox and water effects.
A unofficial fan remake of Half-Life, called Black Mesa was later started development in response of those criticisms, which was first released in 2012 without any Xen chapters and was much shorter, and later in 2020, a full release with contains the Xen chapters.
16 Nov 2004 Half-Life 2 Half-Life 2 EA UK (PS3 port) Source 2004 Source 2004 (launch, Original Xbox)
Source 2007 Source 2007 (only in Xbox 360PlayStation 3)
Source 2013 Singleplayer Source 2013 Singleplayer (currently)
PC: Windows, Mac, Linux

Console(s): Original Xbox, Xbox 360, PlayStation 3

Mobile: Android (NVIDIA Shield)
Sequel to Half-Life, and later Half-Life: Alyx. Included on The Orange Box The Orange Box.
The game was set 20 years after the event of Half-Life, takes place in City 17, which is under Combine control.
Prior to its release, it was delayed multiple times, and infamously leaked in Oct 2003. It was among the first games to require Steam in order to play.
Half-Life 2's engine branch has been updated multiple times, first in 2006 with the release of Episode One, upgrading it to Source 2006, in 2007, upgraded to Source 2007 on consoles, and in 2010, upgraded to Source 2009 on PC, finally, Half-Life 2 was upgraded to the Source 2013 Singleplayer branch.
30 Nov 2004 Half-Life 2: Deathmatch Half-Life 2: Deathmatch Source 2004 Source 2004 (launch)
Source 2013 Multiplayer Source 2013 Multiplayer (currently, earlier version)
PC: Windows, Mac, Linux Multiplayer component of Half-Life 2.
26 Sep 2005 Day of Defeat: Source Day of Defeat: Source Source 2006 Source 2006 (launch)
Source 2013 Multiplayer Source 2013 Multiplayer (currently)
PC: Windows, Mac, Linux Remake of Day of Defeat. Like Half-Life 2: Lost Coast, it also have features later added to Source 2006, such as HDR lighting.
27 Oct 2005 Half-Life 2: Lost Coast Half-Life 2: Lost Coast Source 2006 Source 2006 (launch)
Source 2013 Singleplayer Source 2013 Singleplayer (currently)
PC: Windows, Mac, Linux Originally as part of Half-Life 2, which was cut at some point before it was released, and was developed after the leak happened but was ultimately cut, then later released in 2005 as a HDR lighting technology demo.
It runs on a much newer engine which would soon later be called Source 2006, which was released with the next game, Half-Life 2: Episode One and Half-Life Deathmatch: Source. As of 2024, it runs on Source 2013 Source 2013.
1 May 2006 Half-Life Deathmatch: Source Half-Life Deathmatch: Source Source 2006 Source 2006 (launch)
Source 2013 Multiplayer Source 2013 Multiplayer (currently)
PC: Windows, Mac, Linux Multiplayer component of Half-Life: Source.
1 Jun 2006 Half-Life 2: Episode One Half-Life 2: Episode One EA UK (PS3 port) Source 2006 Source 2006 (launch)
Source 2007 Source 2007 ((only in Xbox 360PlayStation 3))
Source 2013 Singleplayer Source 2013 Singleplayer (currently
PC: Windows, Mac, Linux

Console(s): Xbox 360, PlayStation 3

Mobile: Android (NVIDIA Shield)
The game is the sequel to Half-Life 2, and the story begins after the Citadel reactor core was destroyed, Gordon and Alyx both survived the explosion.
When it's come to technical, it used the Source 2006 Source 2006 engine branch at launch, and it is the last Valve game to be released on the Old Engine branch. Included in The Orange Box The Orange Box.
10 Oct 2007 Half-Life 2: Episode Two Half-Life 2: Episode Two EA UK (PS3 port) Source 2007 Source 2007 (launch, currently used on Xbox 360 & PlayStation 3)
Source 2013 Singleplayer Source 2013 Singleplayer (currently)
PC: Windows, Mac, Linux

Console(s): Xbox 360, PlayStation 3

Mobile: Android (NVIDIA Shield)
A sequel to Half-Life 2: Episode One. The City 17 has been destroyed, and the Citadel was partially collapsed, Gordon and Alyx has survived the train crash. The game largely take places in White Forest. Story aside, when it's come to technical, it uses the Source 2007 Source 2007 at launch, originally called as The Orange Box engine branch and it is the first iteration of the New Engine branch. Included on The Orange Box The Orange Box.
Portal Portal PC: Windows, Mac, Linux

Console(s): Xbox 360, PlayStation 3, Nintendo Switch (part of Portal Companion Collection)

Mobile: Android (NVIDIA Shield)
A completely new game and IP from Valve, set in the Half-Life universe, and take places in Aperture Laboratories. It is a puzzle-based shooter game, allowing you to create portals, that link to one another on any flat and large enough surface.
In 2023, an unofficially remastered version of the game, Portal with RTX, was released, which takes advantage of hardware that support ray-tracing, and adds PBR textures, high polygon models in order to improve the game graphics.
Like the other two new games in The Orange Box package, it used the Source 2007 Source 2007 engine at launch.
Team Fortress 2 Team Fortress 2 Source 2007 Source 2007 (launch, currently used on Xbox 360 & PlayStation 3)
Source 2013 Multiplayer Source 2013 Multiplayer (currently)
PC: Windows, Mac, Linux

Console(s): Xbox 360, PlayStation 3

Mobile: Android (NVIDIA Shield)
Sequel to Team Fortress Classic, focusing on cartoon graphics unlike the pre-release footage/screenshots, which aimed to be more realistic. This is the last game, along with 2 other games as part of The Orange Box pack to use the engine branch that requires Half-Life 2 assets to operate.
The console version of the game is no longer updated, as opposed to PC version of the game, which is frequently updated.
17 Nov 2008 Left 4 Dead Left 4 Dead Turtle Rock Studios
(under Valve South)
Left 4 Dead engine branch Left 4 Dead engine branch (earlier version) PC: Windows, Mac
Console(s): Xbox 360
A new multiplayer co-op game, with a horror zombie theme. It use a new engine branch which does not require Half-Life 2 assets in order to work, it also adds many new features and introduced VPKs.
17 Nov 2009 Left 4 Dead 2 Left 4 Dead 2 Left 4 Dead engine branch Left 4 Dead engine branch PC: Windows, Mac, Linux
Console(s): Xbox 360
Originally was planned to be an update for Left 4 Dead, it was later released as standalone game. Like Left 4 Dead, it also runs on the same L4D branch, but much newer.
Like TF2, the console version (Xbox 360) of the game is no longer updated, as opposed to PC version of the game.
This game was also ported to Source 2 back in 2014, but this version remains unreleased to this day, and one of its maps has been remade in Source 2 as a tech demo back in 2010, which its image was leaked in 2014.
19 Jul 2010 Alien Swarm Alien Swarm Alien Swarm engine branch Alien Swarm engine branch PC: Windows A co-op alien shooter, which was a remake of the Unreal Tournament 2004 mod with the same name. It succeeded the Left 4 Dead engine branch Left 4 Dead engine branch and adds new features on its branch.
18 Apr 2011 Portal 2 Portal 2 Portal 2 engine branch Portal 2 engine branch PC: Windows, Mac, Linux
Console(s): Xbox 360, PlayStation 3, Nintendo Switch (part of Portal Companion Collection)
Has its own engine branch, and once again, introduced new features and succeeded Alien Swarm engine branch Alien Swarm engine branch. Sequel of Portal. For the first time since 2007, the PlayStation 3 version was developed by Valve themselves, and does not suffer various issues that The Orange Box on PS3 had, such as poor optimization, and high-pitched audio issue.
21 Aug 2012 Counter-Strike: Global Offensive Counter-Strike: Global Offensive Hidden Path Entertainment CS:GO engine branch CS:GO engine branch PC: Windows, Mac, Linux
Console(s): Xbox 360, PlayStation 3
Sequel to Counter-Strike: Source, originally developed as a Xbox 360 port of Counter-Strike: Source before Valve eventually turned it into a new Counter-Strike game.

The game runs on the CS:GO engine branch, which is based off of the Left 4 Dead engine branch with Portal 2 engine branch code. CS:GO used Source 1 engine until 2023, now uses the new Source 2 engine under the name Counter-Strike 2, replacing CS:GO (except the console version). Console version is no longer updated since 2013, but remains purchasable.
Prior to being delisted, it was Free to Play on PC since 2018.
9 Jul 2013 Dota 2 Dota 2 Dota 2 engine branch Dota 2 engine branch (Pre-Reborn) PC: Windows, Mac, Linux Sequel to 2003's Warcraft III mod, Defense of the Ancients (retroactively called as Dota 1, DotA for short). Formerly using Source until 2015, when it was switched to Source 2, as part of Dota 2's Reborn update. This is also the last Valve game to be released on the Source engine.
Release date Title Co-developed with Engine branch Platforms Notes

Third-Party

Games, tool and mods made by third-party companies and mod teams.

Released

2004 - 2019
2020 - present (edit)
Year Title Developer(s) Publisher(s) Engine branch Platforms Notes
2020 Black Mesa Black Mesa Crowbar Collective Crowbar Collective Xengine Xengine PC: Windows, Linux Black Mesa was originally released in 2012 as a mod running on Source 2007. Fan remake of Half-Life Half-Life.
2020 G-String Eyaura LunchHouse Software Source 2013 Source 2013 PC: Windows
2021 Portal Reloaded Portal Reloaded PORTAINIS PORTAINIS Portal 2 engine branch Portal 2 engine branch PC: Windows, Mac, Linux
2022 Divinia Chronicles: Relics of Gan-Ti Divinia Chronicles: Relics of Gan-Ti Team Monkey Team Monkey Source 2013 Singleplayer Source 2013 Singleplayer PC: Windows
2022 BrainBread 2 BrainBread 2 Reperio Studios Reperio Studios Source 2013 Multiplayer Source 2013 Multiplayer PC: Windows, Mac, Linux Originally available as Early Access in 2016.
2022 Entropy : Zero 2 Entropy : Zero 2 Breadman Breadman Source 2013 Singleplayer Source 2013 Singleplayer (Mapbase Mapbase) PC: Windows Sequel to Entropy : Zero Entropy : Zero.
2022 They Hunger: Source They Hunger: Source Post-GoldSOURCE Post-GoldSOURCE Source 2013 Singleplayer Source 2013 Singleplayer PC: Windows
2022 Jabroni Brawl: Episode 3 Jabroni Brawl: Episode 3 Team Jabroni Team Jabroni CS:GO engine branch CS:GO engine branch PC: Windows, Linux
2023 Mistake: Source Mistake: Source NOUG4AT Unified Network Source 2013 Singleplayer Source 2013 Singleplayer PC: Windows
2023 Military Conflict: Vietnam Military Conflict: Vietnam Dustfade Dustfade CS:GO engine branch CS:GO engine branch PC: Windows, Linux
2023 Swelter Swelter SnowDropEscape development team Eduard Rostovtsev, SnowDropEscape development team Source 2013 Singleplayer Source 2013 Singleplayer PC: Windows, Linux
2024 Portal: Revolution Portal: Revolution Second Face Software Second Face Software Strata Source Strata Source PC: Windows, Linux First Source Source game to use Strata Source Strata Source engine, a heavily modified version of Source which features many changes and improvements to bring it closer to modern standards.
Year Title Developer(s) Publisher(s) Engine branch Platforms Notes

In development (Unreleased)

This section are for unreleased third-party games and tools that have been announced, and it is currently in development, not publicly released, is in Beta/Early Access, or planned to be released.

List of Source games currently in development (edit)
Release Date Title Developer(s) Publisher(s) Engine branch Platforms Notes
TBA Infestus Team Infestus Team Infestus Source 2013 Multiplayer Source 2013 Multiplayer PC: Windows, Mac, Linux Currently in closed beta.
TBA Momentum Mod Momentum Mod Momentum Team Momentum Team Strata Source Strata Source PC: Windows, Linux Currently in closed beta.
TBA Half-Life 2 RTX Half-Life 2 RTX Orbifold Studios TBA Source 2013 Singleplayer Source 2013 Singleplayer[confirm] PC: Windows
TBA Portal 2: Community Edition Portal 2: Community Edition P2:CE Team P2:CE Team Strata Source Strata Source PC: Windows, Linux Currently in closed beta.
TBA PUNT PUNT LunchHouse Software LunchHouse Software Portal 2 engine branch Portal 2 engine branch (heavily modified) PC: Windows
Release Date Title Developer(s) Publisher(s) Engine branch Platforms Notes

More Third-party Source Engine games

See also

External links

Todo: How relevant and current these guides are? Keep links to current manuals instead of all at appropriate places. Use Special:LinkSearch for this.