[So you need a game engine? Gamasutra surveys the state of the market in this comprehensive overview of solutions, priced from hundreds to hundreds of thousands of dollars, in an article originally published in Game Developer magazine this summer.]
Perhaps what's most remarkable about talking to the people behind the range of game engines listed in this article is their attitude toward each other.
Despite there being clear competition between some of the technologies -- try Unreal Engine 3, idTech 5, CryENGINE 2, and possibly Source -- the main threat is still viewed as being the internal engine.
Yet, it's the industry's growing acceptance of not-invented-here solutions that underpins the variety of middleware companies and wares now available to developers and publishers.
The success of such middleware has been aided by several different trends. Rising game budgets, the need to mitigate risk factors where possible and the robustness of most of these engines means that even at the top-end, paying a few hundred thousand dollars to be able to get something up and running in weeks not months (or years) has become what could be described as the lesser of two evils.
Of course, some bastions of homegrown technology remain, certain in the knowledge they can come up with something more specific and suited to their actual project.
Issues such as vendors being bought -- need we remind people of the disaster that was EA's acquisition of Criterion (disastrous in terms of RenderWare licensees at least) -- still linger.
But more generally, the rise of middleware should be seen as a good thing. Less focus on technology and more time spent on gameplay was always the sales pitch, and maybe games such as BioShock and Mass Effect are proving it finally works.
Here we look at commercial game engines (listed alphabetically by company name) and give developers an overview of the off-the-shelf solutions available.
Each company's approach to engine design is different and developers who are looking to build their next game on outside technology will find a wide variety from which to choose.
One of the first complete engines designed specifically for the massively multiplayer online market, BigWorld developed out of research at Australia's longest-established game studio, Micro Forte.
It has since spun-out into its own company, and eight years on continues to prove popular both with Eastern publishers such as Japan-based GungHo Online and Chinese online giant Netease as well as US outfits like Cheyenne Mountain and John Romero's Slipgate Ironworks.
Technology-wise, it's split into four basic components: a dynamically load-balanced server infrastructure that can supply a large, contiguous world; live server deployment and maintenance tools; a DirectX 9-class game client including integrated physics and AI; and a collaborative development environment including world, model and particle editors.
The Python scripting language is an important element, enabling you to customise in-game elements without direct code.
Future client features being worked on include new lighting and terrain engines as well as optimization for low-end hardware -- something that is particularly important in terms of ensuring the widest possible audience for online games.
More general planned improvements such as language support for Mandarin, Japanese and Russian, plus better terrain importers and exporters, are expected during 2008.
Bigworld Technology Suite
Features: Dynamic load-balancing server with web console tools such as cluster control and log viewer; client including terrain, animation, special effects, and path-finding engines; world, model and particle editors
Platforms: Linux (server), Windows (client) plus support for Xbox 360, PlayStation 3 and mobile devices
Integration with Other Technologies: Diamondware, Scaleform, Spatial Voice, SpeedTree, Umbra, and Vivox, plus plug-ins for 3ds Max and Maya
Cost: Includes up-front license, ongoing royalty and annual support fee
Released Games Include: Dark and Light (Farlan), Kwari (Kwari)
Games in Development Include: House of Flying Daggers (T2CN), Stargate Worlds (Cheyenne Mountain), TBA (Slipgate Ironworks), TBA (VUG/Sierra Online), TBA (38 Studios), TIAN XIA 2 (Netease)
CryEngine 2 was Heralded by the release of the PC shooter Crysis in 2007 and one issue for German-based studio Crytek has been filtering enquiries from interested parties in order to ensure it's working with clients who can make the most of the engine's capabilities.
Of course, the headline feature remains the engine's graphical quality, with the DirectX 10-class engine offering support for features such as real-time lighting and shadows that do not require pre-baked textures to create time of day and dynamic weather conditions.
Also integrated is a flexible physics engine, which enables the creation of fully destructible environments, and a realistic animation system that can combine motion capture and hand animation.
But in terms of getting good games made quickly, CryENGINE 2 production tools are just as important. The Sandbox game editor offers a collaborative, real-time working environment for game designers and level editors.
Tools include terrain editing, visual programming of features such as AI, special effects creation, facial animation, sound design, and asset management.
This is important as versions of your game can be generated and tested on target platforms without the need for assets to be compiled. Indeed, the only obvious lack is support for Xbox 360 and PlayStation 3, something that's currently in development.
Features: DirectX 10-class renderer with dynamic soft shadows; script-based shader system; asset streaming system, animation system; audio engine; integrated Sandbox 2 game editor including Lua-driven AI system and smart objects; low bandwidth networking
Platforms: PC (Xbox 360 and PS3 in development)
Integration with Other Technologies: Alienbrain, CRI, FMOD, Perforce, and Scaleform, plus plug-ins for 3ds Max, Photoshop and XSI
Cost: pre-visualization, SDK, and SDK plus source licenses available. Price on request
Released Games: Crysis (Crytek)
Games in Development Include: Entropia Universe upgrade (MindArk), Merchants of Brooklyn (Paleo), The Day (Reloaded), Blue Mars (Avatar Reality)
Tracing the history of its Gamebryo technology, U.S. outfit Emergent can claim to offer the longest-lived piece of game graphics middleware. Back in the 1990s, when the company was called NDL, it first released its NetImmerse engine before this was eventually rebranded in 2003 -- something that happened to NDL itself in 2005.
Of course, there's no lineage in terms of legacy code but NetImmerse's reputation as a flexible piece of technology that offered good integration with third-party tools continues with Gamebryo.
Interestingly, both have also proved to be popular clients for MMOG developers, with the likes of Mythic (now EA Mythic) and NCsoft as current licensees. This is perhaps due to the suite of other options that Emergent offers, which also include a server solution for online games.
Another significant piece of technology is Floodgate, a multi-core streaming solution with particular focus for PlayStation 3 developers. As with other engine companies, Emergent has used its position in the industry to encourage smaller third parties to support Gamebryo by integrating their products into its Tech Connection Program.
Finally, features for the summer release include a re-architected geometry pipeline, a new terrain system, integrated GPU instancing and support for SoftImage XSI. The company has now also launched a lower-cost Gamebryo Casual option.
Features: High-end renderer including customizable shaders and object culling; Floodgate stream engine; particle system; scene designer and terrain editor; animation tool; asset viewer
Platforms: PC, PlayStation 3, Wii, Xbox 360
Integration with Other Technologies: AiLive, Anark, Bink Video, CRI, Kynapse, morpheme, Miles, PhysX, ProFX, Scaleform, Speedtree, Umbra and Wwise, plus plug-ins for 3ds Max and Maya
Cost: Options include per SKU, per platform or site license. There is no royalty option.
Released Games Include: Civilization IV (Firaxis), Dark Age of Camelot (EA Mythic), The Elder Scrolls IV: Oblivion (Bethesda), Fallout 3 (Bethesda), Warhammer Online (EA Mythic), Zoo Tycoon 2 (Blue Fang)
Games in Development Include: TBA (NCsoft), TBA (Rockstar), TBA (Shanda), TBA (Sony Online), TBA (The9)
Bethesda's The Elder Scrolls IV: Oblivion
It's safe to say Epic's Unreal Engine 3 is the current, de facto industry standard middleware when it comes commercial game development.
Not only is it used on some level by most major publishers and developers, it's increasingly the favored client solution by MMOG developers while architects, film companies and educators are licensing it as well.
There are two main reasons for this status. The first flows from Epic's historic reputation as one of the prime first person shooter studios thanks to games such as Unreal and Unreal Tournament.
The second, which is more pertinent to Unreal Engine 3, is the engine's transformation from its original PC focus into a robust cross-platform technology, with the company claiming to have the most popular engine across PC, PlayStation 3 and Xbox 360.
It certainly comes with plenty of bells and whistles. As well as the DirectX 10-class game engine, which includes the 64-bit HDR rendering system Gemini, there's a flexible animation system which links into the engine's integrated physics, and the Cascade particle effects system.
Development tools include the UnrealEd content creation suite, and the Kismet visual gameplay language and Matinee cinematic system, while the Java-like UnrealScript simplifies in-game programming.
Unreal Engine 3
Features: HDR renderer including advanced shadowing; texture streaming system; modular material framework; integrated animation, physics and audio; Cascade particle system; Kismet gameplay scripting; Matinee cinematic editor, UnrealEd world editor; UnrealScript
Platforms: PC, PlayStation 3, Xbox 360
Integration with Other Technologies: Beast, Bink Video, Digimask, DivX, Enlighten, FaceFX, GameSpy, Kynapse, morpheme, PhysX, ProFX, Rendez-Vous, Spark, SpeedTree, VoiceIn
Cost: Available on request
Released Games Include: Brothers in Arms: Hell's Highway (Gearbox), Army of Two (EA), BioShock (2K Boston), Gears of War (Epic), Lineage II (NCsoft), Mass Effect (BioWare), Unreal Tournament 3 (Epic)
Games in Development Include: All Points Bulletin (RealTime Worlds), Halo Wars (Ensemble), Various (2K), Various (Activision), Various (EA), Various (NCsoft), Various (Square Enix), Various (THQ)
Epic's Gears of War
If any example were required to illustrate the explosion of indie development combined with the rise of casual, downloadable games, Oregon-based GarageGames' Torque engine and development suite would be it.
Initially created from the skeleton of the PC-based Tribes 2 engine by ex-members of its development team at Dynamix in 2000, the Torque engine has since blossomed to offer various technological options for game makers ranging from hobbyists through to professional studios.
This is reflected in the pricing options that are split into indie and commercial, depending on the size of the licensee.
The simplest option is Torque X 2.0, which is designed for use as part of Microsoft's XNA Game Studio 2.0 for Xbox 360 and PC games, while a similar option for general PC and Mac games is the 2D drag and drop engine, Torque Game Builder.
The 3D version of this is the Torque Game Engine, while Torque Game Engine Advanced includes features such as dynamic lighting, programmable shaders, a terrain rendering system and special effects such as water.
Other flavors of these technologies are specifically available for Xbox 360 and Wii development in the form of Torque 360 and Torque for Wii.
Torque / Game / Builder / Engine / Advanced / X / 360
Features (TGEA): DirectX 9-class renderer including procedural generated shaders and custom materials; Puppeteer Mesh animation system, terrain generation engine, TorqueNet networking, TorqueScripting language; Mission Builder editor
Platforms: Linux, Mac, PC, Wii, Xbox 360
Integration with Other Technologies: Bullet Physics, OGRE, Havok, PhysX, Scaleform and Umbra, plus plug-ins for 3ds Max, Maya, Houdini and XSI
Cost: ranges from $100 per seat to $1,495 commercial license depending on technology. No royalties.
Released Games Include: Curse of the Pharaoh (Ph03nix), Cyclomite (Wideload), Marble Blast Ultra (GarageGames), Think Tanks (BraveTree), Wildlife Tycoon (Pocketwatch), Penny Arcade Adventures (Hothead)
Games in Development Include: Legions (GarageGames), Metal Drift (Black Jacket), TBA (EA), TBA (NCsoft), TBA (Ubisoft), TBA (Vivendi)
GarageGames' Marble Blast Ultra
iDTech 5 was publicly unveiled by John Carmack during the Apple Worldwide Developers Conference 2007 as the next-generation game engine from Texas-based id Software. Of all the engines featured in this roundup, it's the one about which least is known as no games have yet shipped using the technology.
The first to do so will be id's Rage, a vehicle combat game involving large, exterior areas. In this respect, one of the most important features of idTech 5 is the MegaTexture system -- a high-quality streaming technology which treats environments as one very large texture rather than breaking it down into tiled components.
Another element highlighted is the collision system which id claims prevents the typical geometric interpenetrations and collision errors currently seen in games.
Linked into the game engine is the real-time idStudio, which interfaces with the system's development tools and editors, ensuring data consistency and integration with source control solutions. IdStudio also allows you to run game content practically instantaneous on all supported target platforms.
In keeping with other id engines from Quake onwards, IdTech5 supports the OpenGL graphics standard, ensuring core cross-platform support across Mac, PC as well as Xbox 360 and PlayStation 3.
iDTech 4 (iDTech 5 available on a select basis)
Features: HDR rendering; soft shadows; integrated physics, animation, AI and audio engines; MegaTexture system; idStudio development suite
Platforms: Mac, PC, PlayStation 3, Xbox 360
Integration with Other Technologies: interfaces for Alienbrain and DevTrack, plus plug-ins for 3ds Max, LightWave 3D and Maya
Cost: idTech 4, $250,000 guarantee against a 5 percent royalty; idTech 5, available on request
Released Games Include: idTech 4: Doom 3 (id), Quake 4 (Raven), Prey (Human Head), Enemy Territory: Quake Wars (Splash Damage) idTech 5: none
Games in Development Include: idTech 5: Rage (id)
Human Head's Prey
Q Engine is the result of a decade-long development process carried out by DirectX alumni Servan Keondjian and Doug Rabson following their departure from Microsoft. Setting up Qubesoft in North London, they decided to create a from-the-ground-up piece of middleware with particular attention placed on the flexibility of the technology.
To that extent, Q is built as a cross-platform extensible plug-in framework that enables you to customize and add game-specific technologies as you see fit, without modifying existing source code. Features include a texture manager capable of handling large amounts of data, n-dimensional animation blending and data streaming.
The engine also links into the real-time QStudio editing system that lets you run custom plug-ins live while you are developing and testing your game.
It's still an early stage for Q, although it is being used internally by Qubesoft as well as by a number of smaller game developers and virtual world builders.
Ongoing work includes broader integration with other middleware providers, improved debugging for massively multi-threaded script applications, enhanced animation tools and an expanded library of ready-to-use shaders.
Features: Arbitrary scene rendering algorithms, programmable shaders; background data streaming, texture manager; cross-platform data format; n-dimensional animation blending; background work queue; integrated QStudio development environment
Platforms: Linux, Mac, PC, PlayStation 3, Wii
Integration with Other Technologies: Visual Studio 2008
Cost: An annual support fee plus shipping fee per SKU
Released Games Include: Earthsim (Earthsim), LEGO Digital Designer (Qube)
Games in Development Include: Near (Near)
Qube's LEGO Digital Designer
Built on the back of experience stretching into the days of text-based online games, U.S.-based Simutronics' HeroEngine takes a different approach when it comes to the creation and deployment of massively multiplayer online games.
Hero Engine was launched in 2006, and after five years of work, it provides an integrated server-client engine and development system, both of which support a dynamic plug-in architecture that enables a collaborative and 'always live' environment for the fast prototyping, building, and testing of games.
This toolset, called HeroBlade, features components such as a world builder, particle and special effects editors, a character and animation system, an audio engine, and an internal scripting language.
This is linked into a live asset repository for intelligent objects and the DreamManager project management system and quality assurance tools. Further improving the ability for collaboration is a real-time whiteboard tool so you can make notes directly onto in-game levels.
Finally, the server architecture itself is designed to handle seamless environments, instanced worlds, or variants between the two. Performance and player behavior metrics tools are also provided.
Indeed, the only thing missing is a finished game as the length of time to make MMOGs means that no commercial products have yet been shipped using HeroEngine - although the recently announced Star Wars: The Old Republic uses the engine, according to earlier press releases.
Features: HeroBlade development tool; 'always live' client-server; world editor; intelligent objects; character animation system; HeroScript; DreamManager process management system
Platforms: Linux (server), PC (client)
Integration with Other Technologies: AIseek, FMOD, PhysX, RTView, Scaleform, SpeedTree, StreamBase, Wwise and Vivox, plus plug-ins for 3ds Max and Maya
Cost: Evaluation, prototype, basic and source licenses available, price available on request
Released Games Include: none to date
Games in Development Include: Star Wars: The Old Republic (BioWare), TBA (IT Territory), TBA (ZeniMax)
German middleware company Trinigy may not be a household name when it comes to game technology, but over the years it has steadily built up its presence from its central European heartland to pick up clients in Asia, the U.K. and the U.S.
The engine features advanced lighting and shadowing features, with particular attention recently being paid to stream processing and multi-threading.
Other components include integrated physics, animation, particle effects and audio. The next major release of the Vision Engine (version 7) will see significant improvement in areas such as visibility and occlusion processing, instance scripting and support for third-party tools.
In term of game development, the Vision Engine links into the vForge editing framework -- something that's designed to be extended and customized using the C# programming language so gameplay features can be exposed for artists and level editors.
An important part of the system is the vLux light-mapping tool that enables you to pre-process and bake static lighting information into your textures.
Interactive shader editing, the addition of dynamic effects, volumetric effects and camera paths can be carried out within vForge too, while future releases of the tech will include enhancements between the art pipeline and tools such as 3ds Max and Maya.
Features: HDR renderer supporting radiosity-based, normal-mapped illumination; integrated physics, particle, animation, cinematic playback and audio components, vForce development environment including vLux light mapping tool
Platforms: PC, PlayStation 3, Xbox 360 (Wii in development)
Integration with Other Technologies: Bullet Physics, FMOD, Kynapse, ODE Physics, PhysX, ProFX, ScaleForm and SpeedTree, plus plug-ins for 3ds Max and Maya
Cost: per-title/per-platform fee without royalties. Details available on request
Released Games Include: Alarm for Cobra 11 (Exozet), Back to Gaya (4Head), Helldorado (Spellbound), The Show (16Tons), Undercover (Sproing)
Games in Development Include: Dungeon Hero (Firefly), Gothic 4 (Spellbound), Warlord (Neowiz)
Spellbound's Airline Tycoon 2
The Source Engine was developed in the years following Valve's initial licensing of the Quake engine for Half-Life in the mid-1990s.
The strengths of the Source engine reflect the focus the Seattle developer has placed on its own games: high-end graphical effects, facial and character animation, the integration of in-game physics, effective networking code and support for a wide range of PC hardware.
Unlike other middleware companies, Valve seems to have taken a measured approach since it started licensing the engine in 2004, working with a small group of developers rather than the large publishers.
This may be because of Source's PC-centric nature. Wii and PlayStation 3 are supported but licensees are warned such ports will require additional custom work.
Yet, for PC and Xbox 360 development, Source offers a fully featured solution. The renderer supports dynamic shadows and HDR, the latter even on DirectX 9-class hardware, while indirect radiosity is supported using a distributed solver and then baked into textures.
Other engine components include a unified material system covering textures, physical behavior and fracture properties; network-enabled physics; and a squad-based AI system. Development tools include the Hammer level editor, the Faceposer character animator and an audio suite.
Features: DirectX 10 HDR renderer with advanced shaders; material systems; particle engine; networked physics engine; pathfinding and navigation system; Hammer level editor; facial and character animation tool; Faceposer
Platforms: PC, Xbox 360 (PlayStation 3 and Wii available but not officially supported)
Integration with Other Technologies: plug-ins for 3ds Max, Blender, Cinema 4D, FragMOTION, LightWave 3D, Maya, Milkshape 3D and Softimage XSI
Cost: Available on request
Released Games Include: Counter-Strike: Source (Valve), Dark Messiah of Might and Magic (Arkane), Half-Life 2 (Valve), Portal (Valve), Team Fortress 2 (Valve)
Games in Development Include: Left 4 Dead (Turtle Rock Studios), Mabinogi Heroes (Nexon), Postal III (Akella), Salvation (Black Wing), The Crossing (Arkane)
Valve's Half-Life 2
Chapel Hill-based Vicious Cycle launched its Vicious Engine in 2005 as the first technology to offer dedicated support for PSP. In part this arose from its own work on the PSP title, Dead Head Fred, but since then, the first version of the engine has been extended for other platforms such as PC and Wii and is one of the newcomers to the middleware arena.
The forthcoming Vicious Engine 2 will further expand support to include Xbox 360 and PlayStation 3. In order to handle these, new features have been added such as a dynamic lighting system, including the ability to bake lightmaps, an animation blending system, a shader-based material editor, occlusion culling, and better pathfinding and AI functionality.
More generally, one of the main features of the Vicious Engine is its data-driven point-and-click scripting, which the company claims makes it much easier for non-programmers to work with -- something that is particularly important in terms of the fast turnaround projects for which it's typically used.
Working in conjunction with this is a script editor, which enables you to debug gameplay using breakpoints and analyzing object variables and agent AI states. A built-in user interface development tool and an intelligent memory management system are also included.
Vicious Engine (Ver. 2 due "soon")
Features: Dynamic lighting system; animation system; material editor; AI engine, scripting system and debugger
Platforms: PC, PlayStation 3, PSP, Xbox 360, Wii
Integration with Other Technologies: 3ds Max, Maya
Cost: A combination of license fee and support fee on a per-platform basis. Price available on request
Released Games Include: Elements of Destruction (Frozen Codebase), 300: March to Glory (Collision), Alien Syndrome (Totally Games), Dead Head Fred (Vicious Cycle)
Games in Development Include:
Totally Games' Alien Syndrome