Source engine
Developed by	Valve Corporation
Latest release	Protocol 14, Build 3407 / March 6, 2008
Platform	Microsoft Windows, Playstation 3, Xbox (360)
License	Proprietary[1]
Website	http://source.valvesoftware.com/

The Source engine is a 3D game engine developed by Valve Corporation. Its unique features include a large degree of modularity and flexibility, an artist-driven, shader-based renderer, accurate lip sync and facial expression technology, and a powerful, efficient and completely network-enabled physics system. Image File history File links Download high-resolution version (1280x1024, 306 KB) Summary Alyx Vance talks with her father, Eli Vance, and Dr. Isaac Kleiner over a communication screen set up outside the Combine Citadel in the 2006 computer game, Half-Life 2: Episode One. ... Image File history File links No higher resolution available. ... For other uses, see Software developer (disambiguation). ... Valve Corporation is an American video game developer based in Bellevue, Washington, USA, made famous by its first product, Half-Life, which was released in November 1998. ... Code complete redirects here. ... is the 65th day of the year (66th in leap years) in the Gregorian calendar. ... 2008 (MMVIII) will be a leap year starting on Tuesday of the Anno Domini (common) era, in accordance with the Gregorian calendar. ... In computing, a platform describes some sort of framework, either in hardware or software, which allows software to run. ... Windows redirects here. ... The PlayStation 3 , trademarked PLAYSTATION®3,[3] commonly abbreviated PS3) is the third home video game console produced by Sony Computer Entertainment; successor to the PlayStation 2. ... The Xbox is a sixth generation era video game console produced by Microsoft Corporation. ... It has been suggested that Xbox 360 Elite be merged into this article or section. ... A software license is a legal agreement which may take the form of a proprietary or gratuitous license as well as a memorandum of contract between a producer and a user of computer software. ... Proprietary software is software with restrictions on copying and modifying as enforced by the proprietor. ... A website (alternatively, Web site or web site) is a collection of Web pages, images, videos or other digital assets that is hosted on one or several Web server(s), usually accessible via the Internet, cell phone or a LAN. A Web page is a document, typically written in HTML... A game engine is the core software component of a computer video game or other interactive application with real-time graphics. ... Valve Corporation is an American video game developer based in Bellevue, Washington, USA, made famous by its first product, Half-Life, which was released in November 1998. ... Lip synchronization is the synchronization of audio signals (sometimes with corresponding video signals) so that there is no noticeable lack of simultaneity between them. ...

Source supports both 32-bit and 64-bit environments and the Microsoft Windows, Xbox, Xbox 360, and PlayStation 3 platforms (the last being launched with The Orange Box). It debuted in October 2004 with Counter-Strike: Source and Half-Life 2. 32-bit is a term applied to processors, and computer architectures which manipulate the address and data in 32-bit chunks. ... In computing, a 64-bit component is one in which data are processed or stored in 64-bit units (words). ... Windows redirects here. ... The Xbox is a sixth generation era video game console produced by Microsoft Corporation. ... It has been suggested that Xbox 360 Elite be merged into this article or section. ... The PlayStation 3 , trademarked PLAYSTATION®3,[3] commonly abbreviated PS3) is the third home video game console produced by Sony Computer Entertainment; successor to the PlayStation 2. ... Orange Box redirects here. ... ... Half-Life 2 (commonly abbreviated to HL2) is a science fiction first-person shooter computer game that is the sequel to Half-Life. ...

Technology overview

The Source engine allows for improved graphics (on the right) compared to those of its predecessor (GoldSrc, on the left)

For a full overview, see Source Engine Features on the Valve Developer Community Wiki.

Modularity

See Modularity and Notable Upgrades

Rendering

Shader-based

Up to DirectX 9 with Shader model 3.0

3D skybox; an area can be displayed as a skybox with full 3D parallax, at a default scale of 16x.

High dynamic range rendering (see High Dynamic Range Rendering section)

Animation

Any animation can merge seamlessly with any other animation at any time.

Inverse Kinematics to ensure that characters' limbs react to environments

Networked physics

Source's physics simulator is extremely flexible, even online. Here, in a Garry's Mod session, players turned into melons are roped to a Scanner NPC and try to drag it around the map.

Originate from Havok 2 physics engine

Highly-tuned by Valve

Processor-efficient

Software only

Fully networked with low bandwidth requirements

Vehicle physics including torque, power, gears, tire material, suspension and mode.

Audio

Full DSP system

Full Surround sound support

Software only

Scalability

Supports DirectX 6 and upwards^[2]

Modularity allows for all current and future Source projects to scale back to DX6 if they desire

Facial expressions

Full range of human and non-human facial movements

Based on Professor Paul Ekman's Facial Action Coding System

Over eighty-four "digital muscles"

Lip-sync

Works in tandem with facial expressions

Auto-generated, but completely configurable

Stored in sound file itself for localization

Image File history File links Counterstrike-comparison. ... Image File history File links Counterstrike-comparison. ... A demonstration level created by Valve showcasing the GoldSrc engine. ... Shaders are a set of different technologies. ... DirectX is a collection of APIs for handling tasks related to multimedia, especially game programming, on the Microsoft Windows operating system. ... The High Level Shader Language ( HLSL ) is a shader language developed by Microsoft for use with Direct3D, and is very similar to Cg. ... The clouds and sky in this Half-Life: Opposing Force screenshot are part of the skybox. ... For other uses, see Parallax (disambiguation). ... High dynamic range rendering (HDRR or HDR Rendering), also known as high dynamic range lighting, is the rendering of 3D computer graphics scenes by using lighting calculations done in a larger dynamic range. ... Inverse kinematics is the process of determining the movement of interconnected segments of a body or model. ... Image File history File links Download high resolution version (1280x1024, 440 KB) Summary This pre-release Garrys Mod 8. ... Image File history File links Download high resolution version (1280x1024, 440 KB) Summary This pre-release Garrys Mod 8. ... “Garry Newman” redirects here. ... This article is about the physics engine. ... Digital signal processing (DSP) is the study of signals in a digital representation and the processing methods of these signals. ... Multichannel audio is the name for a variety of techniques for expanding and enriching the sound of audio playback by recording additional sound channels that can be reproduced on additional speakers. ... Microsoft DirectX is a collection of application programming interfaces for handling tasks related to multimedia, especially game programming and video, on Microsoft platforms. ... Paul Ekman (born 1934) is a psychologist and has been a pioneer in the study of emotions and facial expressions. ... Facial Action Coding System (FACS) is a system originally developed by Paul Ekman and Wallace Friesen in 1976, to taxonomize every conceivable human facial expression. ... Lip synchronization is the synchronization of audio signals (sometimes with corresponding video signals) so that there is no noticeable lack of simultaneity between them. ... Look up localisation, localization in Wiktionary, the free dictionary. ...

Modularity and notable upgrades

Source is designed from the ground up to be highly modular. This allows for the easy upgrade and modification of certain features without breaking other areas of the engine, or breaking engine continuity (that is to say, there need be no 'version jumps' from 1.0 to 2.0). When coupled with Steam, these updates can be distributed retroactively and automatically. For instance, if Source is upgraded to support hardware physics, every Source title on Steam will instantly benefit. Entirely new features such as High Dynamic Range (HDR) Rendering have been shown to require developer input, however. Steam is a digital distribution, digital rights management, multiplayer and communications platform developed by Valve Corporation. ... A Physics Processing Unit (PPU) is a dedicated microprocessor designed to handle the calculations of physics, especially in the physics engine of video games. ...

High dynamic range rendering

First seen in Day of Defeat: Source, then shortly after in Half-Life 2: Lost Coast, HDR was the first major instance of Source's modularity in use. However, whilst in theory all Source engine games and mods were able to use HDR immediately after its release, the game code required to 'hook in' to the new system was not made available to modders until eleven months later, on August 4, 2006. Official licensees and Valve themselves have all made use of the technology since its release. Day of Defeat (DoD) is a team-based multiplayer World War II first-person shooter computer game. ... High dynamic range rendering (HDRR or HDR Rendering), also known as high dynamic range lighting, is the rendering of 3D computer graphics scenes by using lighting calculations done in a larger dynamic range. ... is the 216th day of the year (217th in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ...

Alyx Vance animated with the Source engine's facial animation system

Image File history File links Download high resolution version (445x703, 48 KB) Summary Version 2 of the Source Engines facial animation/expression system, as seen in Half-Life 2: Episode One. ... Image File history File links Download high resolution version (445x703, 48 KB) Summary Version 2 of the Source Engines facial animation/expression system, as seen in Half-Life 2: Episode One. ... Alyx Vance is a fictional character and digital actor from Valves 2004 First Person Shooter computer game Half-Life 2, and its following episode: Half-Life 2: Episode One. ...

Facial animation 2

When Half-Life 2: Episode One was released on 1 June 2006, it introduced the second version of Valve's facial animation system. Ken Birdwell explains the upgrade's features in the game's commentary track: is the 152nd day of the year (153rd in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... Cartoonish and realistic talking heads. ...

When we designed the Half-Life 2 facial system back in 2000, our goal was to get a natural-looking performance at a moderate distance. For Episode One, we wanted to extend the characters' facial systems to support more intense performances with a wider range of facial expressions, that would hold up better at close range. These facial improvements included increasing the detail around the eyes and mouth, increasing the number of facial shape targets — think of these as movements of muscle groups — by about 50%, rewriting the rules that control how these shapes blend, and increasing the intensity of many of our existing shapes.

Facial animation 3

The 14 May 2007 "Meet the Heavy" Team Fortress 2 trailer revealed the third iteration of Source's facial animation technology, hardware accelerated on video cards. Valve's accompanying press release reads: May 14 is the 134th day of the year (135th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ...

We are pleased to announce that the next generation of facial animation technology for Source will be released in Team Fortress 2. By leveraging the rapid pace of advancement in PC graphics, videogames can now match and actually surpass the facial animation used in feature film and broadcast television production. We've released a video of this real-time, in-game, in-engine facial animation in action in support of ATI's launch of the Radeon HD 2000 series. By running entirely on the GPU of the videocard, the facial animation not only looks dramatically better, but frees up the CPU to perform other tasks like physics or AI.^[3] The graphics processing unit (GPU) codenamed R600 is the foundation of the Radeon HD 2000 series and the FireGL 2007 series video cards developed by ATI Technologies. ...

The animation system was first released in Team Fortress 2.

Soft-Particle system

Team Fortress 2's Pyro, demonstrating real-time lighting, self-shadowing and soft particle technology

During the July 2006 Electronic Arts Summer Showcase press conference, Gabe Newell mentioned that a new "soft-particle" system will be introduced into the Source Engine in Half-Life 2: Episode Two. It was first demonstrated in the July 19 Team Fortress 2 teaser, which showed a remarkably realistic flamethrower in its closing moments. The system is primarily designed for multiprocessor systems. Image File history File links Tf2_pyro_crop. ... Image File history File links Tf2_pyro_crop. ... Team Fortress 2 is a multiplayer team-based first-person shooter, developed by Valve Corporation as part of the game compilation The Orange Box. ... Electronic Arts (EA) (NASDAQ: ERTS) is an American developer, marketer, publisher, and distributor of computer and video games. ... Gabe Newell (born November 3, 1962) is the co-founder and managing director of game development company Valve Corporation. ... Team Fortress 2 is a multiplayer team-based first-person shooter, developed by Valve Corporation as part of the game compilation The Orange Box. ...

Full-screen motion blur

Team Fortress 2 was one of the first Source games to offer full-screen motion blur.^[4] The blur is not the same as the "cinematic" blur used to render Valve's various trailers, and only appears when the player's view is moved at a high speed (e.g. when spinning around or falling). The same effect was also added in Portal and Half-Life 2: Episode Two. Team Fortress 2 is a multiplayer team-based first-person shooter, developed by Valve Corporation as part of the game compilation The Orange Box. ... This amusement ride moved during the exposure. ...

Dynamic lighting and shadowing 2

A new dynamic lighting and shadow mapping system has been developed for Source, complementing the once limited existing system.^[5][6] It launched with the various other new Source features that were developed for Half-Life 2: Episode Two. To meet Wikipedias quality standards, this article or section may require cleanup. ...

In previous Source games, "dynamic" shadows (primarily shadows cast by physics props) would fall in a predetermined direction, manually set by the level designer. With Dynamic Lighting and Shadowing 2, a similar system will be employed — props still usually cast shadows in one general direction — but technology has been developed (and used, albeit sparingly, throughout the Orange Box games) that allows a level designer to enable certain light sources to cast completely dynamic shadow maps. Currently, only one of these shadow-casting light sources is allowed to be visible to the player at one time, a limit imposed at the engine level. To meet Wikipedias quality standards, this article or section may require cleanup. ...

Another improvement with the Dynamic Lighting and Shadowing 2 system is the introduction of flashlight shadows. In previous Source games, the player's flashlight only illuminates an area; with Lighting and Shadowing 2, the flashlight casts dynamic shadows from and onto all nearby objects and geometry, including transparent materials such as chain-link fences, trees and foliage. Flashlight shadows have been enabled for Half-Life 2: Episode Two, but are not available in Team Fortress 2 or Portal (the two other new games released by Valve alongside Episode Two), simply because flashlights are not used in those games. Team Fortress 2 is a multiplayer team-based first-person shooter, developed by Valve Corporation as part of the game compilation The Orange Box. ... This article is about the 2007 computer game. ...

A breakdown of the new lighting system's capabilities is shown below:

Valve Hammer Editor, formerly known as Worldcraft and now commonly called Hammer, is Valve Softwares map creation program for their first-person shooter computer game Half-Life and for all of its mods, sequels, and expansions, as well as all games using the Source engine. ...

Landscape and Flora Rendering

An open gorge environment in Half-Life 2: Episode Two

Large, open natural environments with heavy foliage, traditionally a weakness for the Source engine, is supported as of Half-Life 2: Episode Two. Valve is using alpha-to-coverage for anti-aliasing the alpha textures used to approximate the leaves of foliage. Image File history File links Hl2ep2_gorge. ... Image File history File links Hl2ep2_gorge. ... A gorge is a narrow passage between steep mountains or hills. ... “Foliage” redirects here. ... In digital signal processing, anti-aliasing is the technique of minimizing the distortion artifacts known as aliasing when representing a high-resolution signal at a lower resolution. ...

Cinematic physics tool

Cinematic Physics oversees the destruction of a two-story forest shack

Contrary to expectations, "Cinematic physics" are non-interactive animations baked into one-off model files. They are created with an offline physics tool built by former Weta Digital employee Gray Horsfield, which is not currently available publicly. Image File history File links Hl2ep2_cinematicphysicsshack. ... Image File history File links Hl2ep2_cinematicphysicsshack. ... Weta Digital is a digital visual effects company based in Wellington, New Zealand, an offshoot of the Weta Workshop physical effects company. ...

Multiprocessor optimizations

A hundreds-strong swarm of AI entities avoid danger in a multiprocessor benchmark

As a part of the Source engine's transition to next-generation consoles, multiprocessor optimizations have been added, resulting in faster processing on PC hardware with dual or quad core systems and the Xbox 360 and PlayStation 3 consoles.^[6] Gabe Newell: Image File history File links Source_multicore_critter-avoid-danger. ... Image File history File links Source_multicore_critter-avoid-danger. ... Multiprocessing is traditionally known as the use of multiple concurrent processes in a system as opposed to a single process at any one instant. ... A dual-core CPU combines two independent processors and their respective caches and cache controllers onto a single silicon chip, or integrated circuit. ... It has been suggested that this article or section be merged into Multi-core. ...

Yes. We definitely think that content needs to move forward. For example, one of the things we're reacting to is the speed at which microprocessors are coming out. So, Intel has very aggressively moved up delivery of desktop processors with four different cores; we'll have support for that in Episode Two, and we'll definitely go back to affect, you know, Episode One or Half-Life 2 or Counter-Strike Source, so they can take advantage of that. We'll definitely try to keep the existing games — especially the multiplayer games — current as technology evolves.^[7]

Valve has demonstrated the new multi core optimizations^[8] which use a multi-threading style they dub "hybrid threading." A Source multi-threading update and benchmark are expected to be released at some point, though a date for either and the content of the benchmark are currently unknown.^[9]

Deformable physics bodies

The Orange Box introduced support for physics-based animation for simulation of things such as floppy clothing and flexible hair ("jigglebones"), and better blending of ragdoll physics with predefined animation.^[10] Previously, Source's physics system could not deform objects except between bone connections.

Unconfirmed future technology

In-game development tools

At release, Team Fortress 2's cache files contained leaked code for several in-game development tools:^[11] Team Fortress 2 is a multiplayer team-based first-person shooter, developed by Valve Corporation as part of the game compilation The Orange Box. ...

Source Filmmaker

The tool used to create Valve's promotional trailers. Users can record themselves as many times as they want and overlap the results, creating the illusion of there being many actors in the world at once. A "Publish to Steam" button is available from the main menu. Supports all of the engine's Cinematic effects.

Material editor

A material-editing IDE for tweaking the properties of a texture's 'proxy' Material file. Does not allow for the editing of texture data itself.

Actbusy editor

Another script-file IDE, this time used to tweak the game or mod's AI Actbusy routines.

Commentary editor

A third script IDE, used to tweak Developer Commentary.

Particle editor

A visual editor for Source's soft particle system, which was also introduced with TF2.

VCD Block Editor

Purpose forgotten!

The leaked code has since been both removed from the cache and disabled from running should the user supply backed-up versions of the various libraries. An integrated development environment (IDE), also known as integrated design environment and integrated debugging environment, is a programming environment that has been packaged as an application program,that assists computer programmers in developing software. ...

Cinematic effects

Cinematic effects including depth of field, motion blur and film grain are demonstrated in this video capture

With color correction and film grain already released,^[12] Valve intends to add other cinematic effects such as depth of field to Source when hardware is able to render it to their satisfaction. The effects are accomplished with an accumulation buffer for quality, creating enormous overhead; for instance, twenty to thirty motion blur frames need to be rendered for every one frame that the user sees. For a constant frame rate of thirty frames per second, a video card is required to produce between six hundred and nine hundred frames per second. This causes late 2005-era hardware to require a full two seconds to render each frame.^[13] Image File history File links Download high resolution version (1280x720, 218 KB) Summary A frame from a promotional video demonstrating some of the effects that are to be added to the Source engine in order to give a more period cinematic feel Day of Defeat: Source. ... Image File history File links Download high resolution version (1280x720, 218 KB) Summary A frame from a promotional video demonstrating some of the effects that are to be added to the Source engine in order to give a more period cinematic feel Day of Defeat: Source. ... Film grain or granularity is the random optical texture of processed photographic film due to the presence of small grains of a metallic silver developed from silver halide that have received enough photons. ... In optics, particularly film and photography, the depth of field (DOF) is the distance in front of and beyond the subject that appears to be in focus. ... Frame rate, or frame frequency, is the measurement of the frequency (rate) at which an imaging device produces unique consecutive images called frames. ...

Motion blur and depth of field can be seen in several of Valve's promotional videos, including:

• The Day of Defeat: Source video Prelude to Victory
• The initial Portal trailer [1].
• The Team Fortress 2 trailer Meet the Heavy

Day of Defeat (DoD) is a team-based multiplayer World War II first-person shooter computer game. ... This article is about the 2007 computer game. ... Team Fortress 2 is a multiplayer team-based first-person shooter, developed by Valve Corporation as part of the game compilation The Orange Box. ...

Image-Based Rendering

Image-Based Rendering is a technique in which 2D elements are manipulated to appear in a 3D world. In the context of a 3D game, it delivers a significant performance boost by replacing 3D geometry that is far enough away for the transition to be imperceptible with a 2D image. Implementation of the technology in this role can be found applied to Rome: Total War's soldiers, Far Cry's forests,^[14] and various objects in Guild Wars' environments, such as buildings and flora. 2. ... Rome: Total War is a grand strategy computer game where players fight historical and fictious battles during the era of the Roman Republic, from 270 BCE to 14 CE. The game was developed by Creative Assembly and released on September 22, 2004. ... This article is about the computer game. ... This article is for the Guild Wars series. ...

The technology had been in development for Half-Life 2, as a 2003 interview with Driverheaven.net shows,^[15] but was cut. It was mentioned again by Gabe Newell during 1UP's 'Valve week': ^[16] Half-Life 2 (commonly abbreviated to HL2) is a science fiction first-person shooter computer game that is the sequel to Half-Life. ... Gabe Newell (born November 3, 1962) is the co-founder and managing director of game development company Valve Corporation. ... ...

There's this technology that was really exciting that I’d like to see us get into production, which is a different approach to rendering complexity: Moving things into and out of an image domain and then seamlessly interpolating between those motions as you move around. So that everything close to you is physical and geometry, and everything really far away from you is an image, but you have no way of telling that if you do it properly and things can fly out and come back.

The June 2006 Day of Defeat: Source update included an "image-based texture blending shader",^[17] and Half-Life 2: Episode Two's expansive environments seem ideally suited to the technology, but it has yet to be dated or even officially announced. Day of Defeat (DoD) is a team-based multiplayer World War II first-person shooter computer game. ...

File streaming

One of the technologies developed for Half-Life 2's Xbox release was file streaming, wherein a map's resources could be loaded as the player moved around in it rather than in one operation before playability.^[18] With the system in place, loading times were reduced to as little as fifteen seconds. The system expanded on the caching system already implemented. There is no time frame for its release, as implementing such a system on the potentially infinite variations of PC hardware setups in use poses serious performance problems (see Stutter section). Half-Life 2 (commonly abbreviated to HL2) is a science fiction first-person shooter computer game that is the sequel to Half-Life. ... The Xbox is a sixth generation era video game console produced by Microsoft Corporation. ... The Source engine is a 3D game engine developed by Valve Corporation. ...

Origins

A demonstrational level created by Valve showcasing the GoldSrc engine.

Source distantly originates from the GoldSrc engine, itself a heavily modified version of John D. Carmack's original Quake engine, as is explained by Valve employee Erik Johnson on the Valve Developer Community:^[19] Image File history File links Size of this preview: 800 × 596 pixelsFull resolution (940 × 700 pixel, file size: 160 KB, MIME type: image/jpeg) A demonstrational level created by Valve showcasing the GoldSrc engine. ... Image File history File links Size of this preview: 800 × 596 pixelsFull resolution (940 × 700 pixel, file size: 160 KB, MIME type: image/jpeg) A demonstrational level created by Valve showcasing the GoldSrc engine. ... A demonstration level created by Valve showcasing the GoldSrc engine. ... John D. Carmack II (born August 20, 1970) is a widely recognized figure in the video game industry. ... The Quake engine is the game engine that was written to power 1996s Quake, written by id Software. ... The Valve Developer Community is a MediaWiki wiki used to replace a formal documentation for the Source engine SDK and related Valve projects (such as Steam). ...

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. Half-Life For a quantity subject to exponential decay, the half-life is the time required for the quantity to fall to half of its initial value. ... In software engineering, a project fork or branch happens when a developer (or a group of them) takes a copy of source code from one software package and starts to independently develop a new package. ... Microsoft Visual SourceSafe (VSS) is a source control software package oriented towards smaller software development projects. ... Half-Life 2 (commonly abbreviated to HL2) is a science fiction first-person shooter computer game that is the sequel to Half-Life. ... E³ logo The Electronic Entertainment Expo (or Exposition), commonly known as E³ or E3, is an annual trade show for the computer and video games industry. ...

Source was developed part-by-part from this fork onwards, slowly replacing GoldSrc in Valve's internal projects^[20] and explaining in part the reasons behind its unusually modular nature. Valve's development of Source since has been mixture of licensed middleware (Havok Physics, albeit heavily modified, and MP3 playback) and in-house-developed code. The amount of Quake code remaining in Source is a point of contention.^{[citation needed]} John Carmack commented on his blog in 2004 that "there are still bits of early Quake code in Half-Life 2"^[21] and numerous development interfaces are similar to Quake's, at least at a high level - but with both easily likely of being Valve avoiding reinventing the wheel, neither are indicative of a notable reliance on the older engine. Indeed given the fact that Source's 2003 code leak did not produce any such claims it can only be assumed that no incriminating evidence was to be found. This article is about integration software. ... This article is about the physics engine. ... For other uses, see MP3 (disambiguation). ... To meet Wikipedias quality standards, this article or section may require cleanup. ... Reinventing the wheel is a phrase that means a generally accepted technique or solution is ignored in favor of a locally invented solution. ... The following are problems encountered by Valve Software, Vivendi Universal and gamers before and after the release of the computer game Half-Life 2. ...

Source distances itself further from Quake as time goes on. The multiprocessor update in particular made major architectural changes.

Common issues

Stutter

The Source Engine uses a caching system, whereby the loading of certain resources is handled and managed on the fly, rather than in a single operation behind a traditional loading screen. Texture and sound data are the primary areas in which this occurs. Textures are loaded to memory but only moved to the system's video card when needed and audio files are loaded with an unusual "soundcache" system: only the first 125 milliseconds of each file are pre-cached, and the clip is used to cover the asynchronous buffering of the full sound file in the background when it is first requested. If either system is held up the engine will either freeze or go into a temporary loop until the data arrives. 'Stuttering', or 'hitching' as it is sometimes known, is the result of these pauses. For other uses, see cache (disambiguation). ... RAM redirects here. ... A video card, also referred to as a graphics accelerator card, display adapter, graphics card, and numerous other terms, is an item of personal computer hardware whose function is to generate and output images to a display. ... One millisecond is one-thousandth of a second. ... Asynchrony is the state of not being synchronized. ...

Stuttering is system-dependent issue, making it hard to say when it was resolved. However, since an engine update on 2006-02-07^[22] that featured a limited implementation of Source's full file streaming system from the Xbox complaints have ceased on the official support forums. Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 38th day of the year in the Gregorian calendar. ... The Xbox is a sixth generation era video game console produced by Microsoft Corporation. ...

While stutter could be caused by poor system performance, it was also noted on hardware that should be more than powerful enough to cope with the data rate, and despite many theories, the precise cause has never been fully understood by the public. Most third-party solutions involved bypassing the caching system, as it cannot be directly disabled, or system-specific optimizations (e.g. driver updates). A device driver, or software driver is a computer program allowing higher-level computer programs to interact with a computer hardware device. ...

When Half-Life 2 was first released and stuttering became a widely-known problem, community member Mark McWilliams set up a page covering the issue and Valve's communication and work on resolving it.^[23] Several updates were released by Valve, the effects of which varied from complete fixes for some users to previously smooth systems becoming "infected" with the problem. Half-Life 2 (commonly abbreviated to HL2) is a science fiction first-person shooter computer game that is the sequel to Half-Life. ...

Example (WMV), showing a relatively low level of stutter. The hitches coincide with the drawing of new areas (a process that is by design not visible without debugging tools). Windows Media Video (WMV) is a generic name for the set of video codec technologies developed by Microsoft. ...

Looping audio

The Source Engine suffers from an error whereby the asynchronous loading (see Stutter, above) of a new sound file will cause the engine to lock up with looping audio. Because of the nature of DirectX, once the engine enters such a state it will remain on the screen unless the user blindly terminates the program or reboots their computer. The error occurs in a standard Windows library associated with on-board sound cards, and in some cases can be resolved by decreasing DirectSound Acceleration.^[24] Microsoft DirectX is a collection of application programming interfaces for handling tasks related to multimedia, especially game programming and video, on Microsoft platforms. ... Illustration of an application which may use libvorbisfile. ... A sound card (also known as an audio card) is a computer expansion card that can input and output sound under control of computer programs. ... DirectSound is software supplied by Microsoft that resides on a computer with the Windows operating system. ...

Reports of looping audio crashes increased around the release of Episode One. While it is likely that the spike was simply caused by an unusually high number of players, changes to the engine, of which there were many for the game, cannot be ruled out. It has been noted that people who have been able to play Half-Life 2 without any crashes and audio errors in fact do find Episode One to be more prone to that problem. A steampowered.com forum thread is dedicated to discussing the problem and attempting to work out solutions, although the experience of the thread contributors indicates that most suggested workarounds and fixes do not remedy the problem.^[25]

Criticism

Toolset

The Source SDK tools are criticised for being outdated and difficult to use.^[26] A large number of the tools, including those for texture and model compilation, require varying levels of text-editor scripting from the user before they are executed at the command line with lengthy console commands^[27]. This obtuseness was cited by the University of London when they moved their exploration of professional architectural visualisation in computer games to Bethesda Softworks' Gamebryo-based Oblivion engine after a brief period with Source.^[28] Third-party tools provide GUIs,^[29] but are not supported by Valve. A software development kit (SDK or devkit) is typically a set of development tools that allows a software engineer to create applications for a certain software package, software framework, hardware platform, computer system, video game console, operating system, or similar. ... Website http://www. ... Bethesda Softworks, LLC, a ZeniMax Media Company, is a developer and publisher of computer and video games. ... Gamebryo is computer and video games middleware, originally from Numerical Design Limited (NDL), and is the successor to NDLs NetImmerse engine. ... GUI redirects here. ...

Valve's Hammer Editor, the SDK's world-creation tool, does have an interface, but one that has not changed significantly since its initial release for GoldSrc and the original Half-Life in 1998. A demonstration level created by Valve showcasing the GoldSrc engine. ... Half-Life For a quantity subject to exponential decay, the half-life is the time required for the quantity to fall to half of its initial value. ...

Before the Valve Developer Community Wiki was opened the SDK's user documentation was also often lacking.^[30]

Programming

Unlike most modern game engines, Source requires all program code to be written in C++. This is in particular contrast with the Unreal engine and its UnrealScript language that can be (and is) used to write most game rules in titles developed with it. C++ (pronounced see plus plus, IPA: ) is a general-purpose programming language with high-level and low-level capabilities. ... The Unreal Engine is a widely-used game engine developed by Epic Games. ... UnrealScript is the scripting language of the Unreal engine and is used for authoring game code and gameplay events. ...

In response to this, several Source engine games and mods (including Garry's Mod, Natural Selection 2, Fortress Forever and Smod) have implemented the Lua language. These implementations are not available in either the consumer or licensee SDKs however, and as a result the development communities each have formed (which include entire games and mods running or being developed inside them) cannot migrate to the Source engine in general. “Garry Newman” redirects here. ... For other uses, see Natural selection (disambiguation). ... Fortress Forever is a Half-Life 2 mod that uses the games Source Engine. ... In computing, the Lua (pronounced LOO-ah) programming language is a lightweight, reflective, imperative and procedural language, designed as a scripting language with extensible semantics as a primary goal. ...

Valve Developer Community

On June 28, 2005, Valve opened the Valve Developer Community Wiki. The VDC replaced Valve's static Source SDK documentation with a full MediaWiki-powered community site. Within a matter of days Valve reported that "the number of useful articles [had] nearly doubled". These new articles covered the previously undocumented Counter-Strike: Source bot (added by the bot's author, Mike Booth) and Half-Life 2 AI, source control for Source engine mods, and more. is the 179th day of the year (180th in leap years) in the Gregorian calendar. ... Year 2005 (MMV) was a common year starting on Saturday (link displays full calendar) of the Gregorian calendar. ... This article is about the wiki software. ... ... Revision control is an aspect of documentation control wherein changes to documents are identified by incrementing an associated number or letter code, termed the revision level, or simply revision. It has been a standard practice in the maintenance of engineering drawings for as long as the generation of such drawings...

Licensed Source games

Left 4 Dead

Valve

Counter-Strike: Source

Day of Defeat: Source

Half-Life: Source

Half-Life 2

Half-Life 2 Episodes (One, Two and Three)

Half-Life 2: Deathmatch

Portal

Team Fortress 2

Left 4 Dead

Other developers

Alien Swarm: Infested

The Crossing^[31]

Dark Messiah Might and Magic

Dark Messiah Might and Magic

Garry's Mod

Mabinogi Heroes

Natural Selection 2

Postal III^[32]

Prime

SiN Episodes

The Ship

They Hunger: Lost Souls

Twilight War: After the Fall (production resumed)

Vampire: The Masquerade – Bloodlines

Zeno Clash [2]

Untitled Threewave Software game^[33]

Kuma Reality Games

DinoHunters

Dogfights: The Game

The History Channel's ShootOut! The Game

The Kill Point: Game

KumaWar 2

Salvation [3]

Education and research

VR Worlds 2 [4]

Image File history File links Size of this preview: 648 × 600 pixel Image in higher resolution (1280 × 1185 pixel, file size: 246 KB, MIME type: image/jpeg) Zombies in Left 4 Dead. ... Image File history File links Size of this preview: 648 × 600 pixel Image in higher resolution (1280 × 1185 pixel, file size: 246 KB, MIME type: image/jpeg) Zombies in Left 4 Dead. ... Left 4 Dead is an upcoming multiplayer co-operative survival horror game by Turtle Rock Studios and Valve Corporation (a collaboration that has previously produced Counter-Strike: Condition Zero, as well as maps and the official bot for Valves Counter-Strike: Source). ... ... Day of Defeat (DoD) is a team-based multiplayer World War II first-person shooter computer game. ... Half-Life 2 (commonly abbreviated to HL2) is a science fiction first-person shooter computer game that is the sequel to Half-Life. ... Half-Life 2: Episode One is the first of a trilogy[1] of expansion episodes for the 2004 first-person shooter PC game, Half-Life 2. ... This article is about the 2007 computer game. ... Team Fortress 2 is a multiplayer team-based first-person shooter, developed by Valve Corporation as part of the game compilation The Orange Box. ... Left 4 Dead is an upcoming multiplayer co-operative survival horror game by Turtle Rock Studios and Valve Corporation (a collaboration that has previously produced Counter-Strike: Condition Zero, as well as maps and the official bot for Valves Counter-Strike: Source). ... The Crossing is an upcoming multiplayer co-operative game by Arkane Studios with the help of the art director from Half-Life 2. ... Image File history File links Download high resolution version (1024x819, 377 KB) Summary Dark Messiah of Might and Magic Licensing This is a screenshot of a copyrighted computer game or video game, and the copyright for it is most likely held by the company that developed the game. ... Image File history File links Download high resolution version (1024x819, 377 KB) Summary Dark Messiah of Might and Magic Licensing This is a screenshot of a copyrighted computer game or video game, and the copyright for it is most likely held by the company that developed the game. ... “Garry Newman” redirects here. ... To meet Wikipedias content policies and video game article guidelines, this article or section may require cleanup. ... For other uses, see Natural selection (disambiguation). ... Postal III is the sequel to Postal², developed by Running With Scissors, Inc. ... SiN Episodes is the title of a series of episodic games for the PC that would have expanded upon the 1998 computer game SiN. A total of nine episodes were planned with only the first one released. ... The Ship is a first person shooter computer game utilising Valve Softwares Source engine developed at Outerlight Ltd. ... They Hunger is a single player horror based mod of Valves first-person shooter Half-Life. ... Threewave Software is a videogame developer based in Vancouver, Canada. ... The Dinohunters is a free first person shooter and machinima series created by Kuma Reality Games. ... Dogfights: The Game is a free episodic, combat flight simulator PC game that is based on the History Channel television show Dogfights. ... Shootout! is a game developed by the Kuma Reality Games (the developers of KumaWar). ... The Kill Point: Game is a free episodic, first person shooter, PC game that is based on the television show The Kill Point, which aired on Spike TV. The game has been developed by Kuma Reality Games, a developer which primarily makes freeware games. ... KumaWar KumaWar is a tactical first and third-person shooter created by the new American company Kuma Reality Games. ...

Papers

Valve staff produce several papers each year for the various events and publications, including SIGGRAPH, Game Developer Magazine and Game Developers Conference, detailing different aspects of Source's development at a high level and for expert audiences. SIGGRAPH 2005 official logo SIGGRAPH (short for Special Interest Group in Graphics) is the name of the annual conference on computer graphics convened by the ACM SIGGRAPH organization. ... Game Developer magazine is a monthly trade periodical for the video game industry. ... The Game Developers Conference (GDC) is the largest annual gathering of professional video game developers, focusing on learning, inspiration, and networking. ...

The papers are listed at valvesoftware.com/publications.html.

See also

• Game engine
• Source SDK

A game engine is the core software component of a computer video game or other interactive application with real-time graphics. ... The Source SDK (or Source software development kit) is a collection of tools compiled by Valve Software that is used to create levels or full-on Half-Life 2 modifications (or mods). ...

References