|Stable release||4.11 / March 31, 2016|
|Preview release||4.12 / April 27, 2016|
|Available in||English, Korean, Chinese, Japanese|
The Unreal Engine is a game engine developed by Epic Games, first showcased in the 1998 first-person shooter game Unreal. Although primarily developed for first-person shooters, it has been successfully used in a variety of other genres, including stealth, MMORPGs, and other RPGs. With its code written in C++, the Unreal Engine features a high degree of portability and is a tool used by many game developers today.
Unreal Engine 1
|Initial release||Unreal build 100 / May 1998|
|Stable release||Unreal Tournament build 436 / November 2000|
|Written in||C++ , UnrealScript, Assembly|
|Platform||Microsoft Windows, Linux, Mac OS and OS X, Dreamcast, PlayStation 2|
Making its debut in 1998 with Unreal, the first generation Unreal Engine integrated rendering, collision detection, AI, visibility, networking, scripting, and file system management into one complete engine. Unreal Engine 1 provided an advanced software rasterizer and a hardware-accelerated rendering path using the Glide API, specifically developed for 3dfx GPUs, and was updated for OpenGL and Direct3D. The release of Unreal Tournament marked great strides in both network performance and Direct3D and OpenGL support.
The engine became popular due to the modular engine architecture and the inclusion of a scripting language called UnrealScript, which made it easy to mod, including total conversions like Tactical Ops.
From the start, the engine was designed in a way to be extensible and improved over multiple generations of games, as creator and founder of Epic Games Tim Sweeney stated in a 1998 interview with magazine Maximum PC.
Unreal Engine 2
|Initial release||Unreal Warfare build 633 / January 2001|
|Stable release||Unreal Engine 2.5 build 3369 / November 2005|
|Written in||C++ , UnrealScript|
|Platform||Microsoft Windows, Linux, OS X, Xbox, PlayStation 2, GameCube|
The second version was released in 2002 with America's Army, a free multiplayer shooter created by the US Army and financed by the U.S. government. This generation saw the core code and rendering engine completely re-written. In addition, it featured UnrealEd 2, a level editor, which debuted with the previous generation of the engine and was shortly followed later by UnrealEd 3, along with the Karma physics SDK. This physics engine powered the ragdoll physics in Unreal Tournament 2003 and Unreal Championship. Other engine elements were also updated, with improved assets as well as adding support for the GameCube and the Xbox. Support for the PlayStation 2 console was previously added in UE1. Taking Xbox aside, both GameCube and PS2 were never supported directly by Epic, support being instead farmed out to Secret Level. As such, third parties looking to use further Unreal Engine revisions had to do their own builds throughout the generation, as they had to in more recent years with the Wii, X360, PS3, PSP, and 3DS.
UE2.5, an update to the original version of UE2, improved rendering performance and added vehicles physics, a particle system editor for UnrealEd, and 64-bit support in Unreal Tournament 2004. A specialized version of UE2.5 called UE2X was used for Unreal Championship 2: The Liandri Conflict on the original Xbox platform. It features optimizations specific to that console. EAX 3.0 is also supported for sound.
Unreal Engine 3
|Initial release||Unreal Engine 3 build 100 / March 2004|
|Stable release||Unreal Engine 3 build 12791.2424394 / February 2015|
|Written in||C++, C#, UnrealScript, GLSL, Cg, HLSL|
|Platform||Microsoft Windows, Linux, OS X, Xbox 360, PlayStation 3, Wii U, Android, iOS, Windows RT, and PlayStation Vita, Adobe Flash Player, HTML5|
The first screenshots of Unreal Engine 3 were presented in 2004, at which point the engine had already been in development for 18 months. Unlike Unreal Engine 2, which still supported fixed-function pipeline, Unreal Engine 3 was designed to take advantage of fully programmable shader hardware (in DirectX 9 terms, it required shader model 3.0). All lighting calculations were done per-pixel, instead of per-vertex. Unreal Engine 3 supports a gamma-correct high-dynamic range renderer.
Initially, Unreal Engine 3 only supported Windows, Xbox 360, and PlayStation 3 platforms, while Android and iOS were added later in 2010 (with Infinity Blade being the first iOS title and Dungeon Defenders the first Android title). OS X support was added in 2011. Its renderer supports techniques including HDRR, per-pixel lighting, and dynamic shadows. In October 2011, the engine was ported to support Adobe Flash Player 11 through the Stage 3D hardware-accelerated APIs. Epic has used this version of the engine for their in-house games. Aggressive licensing of this iteration has garnered a great deal of support from many prominent licensees. Epic has announced that Unreal Engine 3 runs on both Windows 8 and Windows RT. The first released console game using Unreal Engine 3 was Gears of War and the first released PC game was RoboBlitz.
Throughout the lifetime of UE3, significant updates have been incorporated, including a global illumination solver, improved destructible environments, soft body dynamics, large crowd simulation, iPod Touch functionality, Steamworks integration, a real-time global illumination solution, and stereoscopic 3D on Xbox 360 via TriOviz for Games Technology. DirectX 11 support was demonstrated with the Samaritan demo, which was built by Epic Games in a close partnership with NVIDIA, with engineers working around the country to push real-time graphics to a new high point.
In addition to the game industry, UE3 has also seen adoption by many non-gaming projects. The popular children's TV show LazyTown used UE3 during filming to generate virtual sets for real-time integration with footage of actors and puppets performing in front of green screens. In March 2012, the FBI licensed Epic's Unreal Engine 3 to use in a simulator for training. The animation software "Muvizu Play", which was released in April 2013, uses UE3.
Unreal Development Kit
|Initial release||v5860 / November 2009|
|Stable release||v12791.2424394 / February 2015|
|Written in||C++, C#, UnrealScript, GLSL, Cg, HLSL|
|Operating system||Microsoft Windows|
|Platform||Microsoft Windows, OS X, iOS|
|Type||Level editor / Software development kit|
|License||Free for noncommercial use|
UDN for UDK
While Unreal Engine 3 has been quite open for modders to work with, the ability to publish and sell games made using UE3 was restricted to licensees of the engine. However, in November 2009, Epic released a free version of UE3's SDK, called the Unreal Development Kit (UDK), that is available to the general public.
Unreal Engine 4
|Initial release||Unreal Engine 4 build 8967 / May 2012|
|Stable release||Unreal Engine 4.11 / March 31, 2016|
|Written in||C++, C#, GLSL, Cg, HLSL; UnrealScript removed|
|Platform||Microsoft Windows, Linux, OS X, Xbox One, PlayStation 4, HTML5, iOS, Android,|
|License||Free to use, with access to source code; 5% of gross revenue after the first US$3,000 per product per quarter|
On August 17, 2005, Mark Rein, the vice-president of Epic Games, revealed that Unreal Engine 4 had been in development since 2003. Until mid-2008, development was exclusively done by Tim Sweeney, CEO and founder of Epic Games. The engine targets the eighth generation of consoles, PCs and Tegra K1-based devices running Android announced in January 2014 at CES.
In February 2012, Mark Rein said "people are going to be shocked later this year when they see Unreal Engine 4". Unreal Engine 4 was unveiled to limited attendees at the 2012 Game Developers Conference, and video of the engine being demonstrated by technical artist Alan "Talisman" Willard was released to the public on June 7, 2012 via GameTrailers TV. This demo was created on a PC with triple GeForce GTX 580 (tri SLI) and can be run on a PC with a GeForce GTX 680.
One of the major features planned for UE4 was real-time global illumination using voxel cone tracing, eliminating pre-computed lighting. However, this feature has been replaced with a similar but less computationally-expensive algorithm prior to release for all platforms including the PC because of performance concerns on next-generation consoles. UE4 also includes new developer features to reduce iteration time, and allows updating of C++ code while the engine is running. The new "Blueprint" visual scripting system (a successor to UE3's "Kismet") allows for rapid development of game logic without using C++, and includes live debugging. The result is reduced iteration time, and less of a divide between technical artists, designers, and programmers.
[In older engines], if you wanted to change the relationship between your weapon damage and how long it'll take to kill a creature, you may spend a couple of days iterating, but if you have to spend a lot of time waiting for a build every time, you're talking one change, waiting 15 minutes for the compile to complete, and then play the game, get to the point where you can test it, test it, exit the game, change, compile... Now, since all of that can be done very quickly within the tools, it's 'Make the change, play, when it compiles, finish, shoot the guy, and then escape, make the change, play'. The iteration time is down to 30 seconds instead of 15 minutes. Our ability to kind of roll through and see how the game is playing out is much faster.
On March 19, 2014, at the Game Developers Conference, Epic Games released Unreal Engine 4, and all of its tools, features and complete C++ source code, to the development community through a new subscription model. Anyone can sign up for UE4 for Windows, OS X, iOS and Android by paying $19 per month, plus 5% of gross revenue resulting from any commercial products built using UE4. CEO and founder of Epic Games, Tim Sweeney, said that the new business model is a reflection of changes in the industry. Epic Games has traditionally made its Unreal Engine available to large AAA game development teams at a cost of millions of dollars but as the industry has evolved, Epic has had to "really rethink our whole business as to how we make the engine available to teams." "Looking at the new shape of the industry now, we realize that's an outdated tool," Sweeney said. "Looking at the possibilities for the engine, we started from scratch and thought 'How can we make the engine available to more people?'". According to the Unreal Engine website, subscribers to the engine will be able to cancel and renew their subscription at any time. They will be able to retain access to UE4 tools, but will not receive access to future releases of Unreal Engine 4.
On September 3, 2014, Epic Games launched the Unreal Engine Marketplace, allowing UE4 subscribers to buy and sell community-created content of all shapes and sizes. In addition to all of the previously released free content, the new marketplace came with a variety of asset packs including full-scale environments, props, characters, sounds, materials, animated meshes, prefab C++ code and a number of other asset types as well as free demos and tutorials.
On September 4, 2014, Epic released Unreal Engine 4 to schools and universities for free, including personal copies for students enrolled in accredited video game development, computer science, art, architecture, simulation, and visualization programs.
|Typing discipline||Static, strong, safe|
|Filename extensions||.uc .uci .upkg|
UnrealScript (often abbreviated to UScript) is Unreal Engine's native scripting language used for authoring game code and gameplay events before the release of Unreal Engine 4. The language was designed for simple, high-level game programming. The UnrealScript interpreter was programmed by Tim Sweeney, who also created an earlier game scripting language, ZZT-oop.
Similar to Java, UnrealScript is object-oriented without multiple inheritance (classes all inherit from a common Object class), and classes are defined in individual files named for the class they define. Unlike Java, UnrealScript does not have object wrappers for primitive types. Interfaces are only supported in Unreal Engine generation 3 and a few Unreal Engine 2 games. UnrealScript supports operator overloading, but not method overloading, except for optional parameters.
In March 2014 Epic announced that the Unreal Engine 4 would no longer be supporting UnrealScript, but instead support game scripting in C++. Visual scripting would be supported by the Blueprints Visual Scripting system, a replacement for the earlier Kismet visual scripting system.
The Unreal engine technology is licensed to many notable entities in the fields of education, training simulation, construction simulation, virtual reality, and CG animation. Licensees include many universities, corporations, the U.S. Army the U.S. Air Force, NASA the Federal Bureau of Investigation (FBI), the Michigan Department of Transportation (MDOT), and the U.S Department of Homeland Security (DHS).
Awards and accolades
Unreal Engine 3 received the Game Developer Magazine Front Line Awards for "Best Game Engine" (2004, 2005, 2006, 2007, Hall of Fame, 2009, 2010, 2011, 2012). It received IGN's Best of E3 2005: "Best Graphics Technology (Xbox 360)" and "Technological Excellence". It received North Carolina Technology Association 21 Awards' for "Top Industry Driven Technology of the Year" (2008, 2011) and "Best Product or Service" (2012). It received the Develop Industry Excellence Awards "Best Game Engine" (2009, 2010, 2011).
Unreal Engine 4 received GamesRadar's E3 2012 Important Stuff Awards for "Best Taste of Next-Gen". It received IGN's Best of E3 2012 for "Coolest Tech", Game Informer's Best of E3 2012 Awards for "Best Tech", Develop Industry Excellence Awards 2013 for "Best Game Engine", and Develop 100: The Tech List 2014 for "Best Game Engine"
Games using the Unreal Engine
- Horvath, Stu (May 17, 2012). "The Imagination Engine: Why Next-Gen Videogames Will Rock Your World". Wired. Condé Nast. Archived from the original on May 30, 2015. Retrieved February 6, 2015.
- Steiner, Brian (June 24, 2013). "How the Unreal Engine Became a Real Gaming Powerhouse". Popular Mechanics. Hearst Corporation. Archived from the original on May 30, 2015. Retrieved October 6, 2014.
- Handrahan, Matthew (March 12, 2014). "Microsoft: DX12 will improve Xbox One performance". Game Industry. Retrieved 2014-09-04.
- The OUYA team (January 26, 2015). "Unreal Engine On The Ouya". Unreal Engine Blog. Epic Games. Retrieved January 28, 2015.
- Shadden, Ian (June 4, 2014). "Unreal Engine 4.2 Release". Unreal Engine. Epic Games. Retrieved 2014-09-04.
- Mozilla (March 12, 2014). "Mozilla and Epic Preview Unreal Engine 4 Running in Firefox". The Mozilla Blog. Retrieved October 4, 2014.
- Anderson, Steve (March 17, 2014). "HTML5 Gaming Just Got Faster with Unreal Engine 4". HTML5 Report. Retrieved October 4, 2014.
- McWhertor, Michael (April 1, 2014). "Epic Games' Sweeney on the future of Unreal, VR and democratic game development". Polygon. Retrieved October 4, 2014.
- "First videogame created with the Unreal Engine". Guinness World Records. January 1, 1998. Retrieved November 22, 2015.
- Edwards, Benj (May 25, 2009). "From The Past To The Future: Tim Sweeney Talks". Gamasutra. UBM plc. Retrieved February 8, 2015.
- "Unreal Engine 1". Retrieved 2012-06-17.
- Paul Lily (July 21, 2009). "Doom to Dunia: A Visual History of 3D Game Engines". Maximum PC. Retrieved 2009-07-05.
- "History of Unreal - Part 1". beyondunreal.com. May 31, 2005. Retrieved 2009-07-05.
- "History of Unreal - Part 1". beyondunreal.com. May 31, 2005. Retrieved 2009-07-05.
Probably the biggest draw to Unreal was the ability to mod it. Tim Sweeney (Founder of Epic) wrote a simple scripting engine into the game called UnrealScript.
- Jason Busby, Zak Parrish, Jeff Wilson (July 21, 2009). "Introduction to Unreal Technology". InformIT. Retrieved 2009-08-08.
- McDonald, T. Liam (November 1998). "Maximum PC" 3 (10): 43. ISSN 1522-4279.
- Parrish, Kevin (25 March 2011). "Ubisoft: 3DS Can Handle Unreal Engine 2. Ubisoft is reportedly using Epic's Unreal Engine 2 for Splinter Cell 3DS". Tom's Guide. Retrieved 28 January 2016.
- Ivan, Tom (March 24, 2011). "Ubisoft: We have Unreal Engine running on 3DS. Splinter Cell publisher seemingly succeeds where Epic has failed". Computer and Video Games. Future plc. Archived from the original on 9 February 2015. Retrieved February 9, 2015.
- "UDK - CodingStandard". Retrieved April 17, 2015.
- "UDK - ColorGrading". Epic Games.
- Epic Games. "Epic Games Releases "Epic Citadel" for Android - News - Epic Games". Retrieved April 17, 2015.
- "Unreal Engine 3 Debuts on Windows 8". Retrieved April 17, 2015.
- "Epic Games Announces Unreal Engine 3 Support for Adobe Flash Player". Retrieved April 17, 2015.
- "Tappy Chicken". Retrieved April 17, 2015.
- Thorsen, Tor (May 13, 2004). "First Look: Unreal Engine 3.0". GameSpot.
- Reed, Kristan (July 1, 2004). "Unreal Engine 3 Interview". Eurogamer.
- Grant, Christopher (September 19, 2011). "Unreal Engine 3 comes to Mac OS X, courtesy of September UDK release". Joystiq.
- Mitchell, Richard (2012). "Unreal Engine 3 now on Windows 8 and Windows RT". Joystiq.
- Callaham, John (March 19, 2009). "Epic Games to show off new Unreal Engine 3 features at GDC". Big Download.
- Shimpi, Anand Lal (December 29, 2009). "Epic Demonstrates Unreal Engine 3 for the iPod Touch, iPhone 3GS". AnandTech.
- "Steamworks Integration Now Available to Unreal Engine 3 Licensees". Epic Games. March 11, 2010.
- "Geomerics Enlighten".
- "Geomerics Announces New Enlighten Integration with Unreal Engine 3".
- Ingham, Tim (June 17, 2010). "E3 2010: Epic makes 3D Gears Of War 2 - We've seen it. It's mega. But retail release not planned". Computer and Video Games.
- "TriOviz for Games Technology Brings 3D Capabilities to Unreal Engine 3". Epic Games. October 6, 2010.
- Fletcher, JC (October 11, 2010). "Epic's Mark Rein goes in-depth with Unreal Engine 3's TriOviz 3D". Joystiq.
- "UDK March 2011 Release".
- "Slide 1" (PDF). Retrieved 2011-08-02.
- Hamilton, Kirk (February 8, 2013). "Apparently, The Story Behind Epic's Dazzling 2011 Tech Demo Is A 'Doozy'". Kotaku. Retrieved October 4, 2014.
- Gies, Arthur (March 18, 2014). "Epic Games working on new, unannounced IP (UPDATE)". Polygon. Retrieved October 4, 2014.
- Gaudiosi, John (September 21, 2011). "Epic Games Founder Tim Sweeney Pushes Unreal Engine 3 Technology Forward". Forbes. Retrieved October 4, 2014.
- "Unreal Engine 3 Powers Critical and Commercial Success LazyTown". Epic Games. Retrieved 2011-02-08.
- BBC News (March 28, 2012). "Unreal games engine licensed to FBI and other US agencies". BBC News. BBC. Retrieved February 6, 2015.
- "Muvizu 3D web site". Movizu.
- Palomino, Sean (January 30, 2015). "February 2015 Unreal Development Kit (UDK) Available for Download". Epic Games Forums. Epic Games. Retrieved February 9, 2015.
- IGN Staff (November 5, 2009). "Epic Games Announces Unreal Development Kit, Powered By Unreal Engine 3". IGN. Retrieved 2014-09-14.
- Wilde, Tyler (March 19, 2014). "Unreal Engine 4 tools and source code now available for a $19 monthly subscription". PC Gamer. Future plc. Retrieved February 9, 2015.
- IGN Staff (December 16, 2010). "Epic Games Releases Unreal Development Kit With iOS Support". IGN. Ziff Davis. Retrieved September 14, 2014.
- Epic Games (December 16, 2010). "Epic Games releases December 2010 Unreal Development Kit Beta with iOS Support". Epic Games. Retrieved February 9, 2015.
- Nutt, Christian (March 21, 2014). "Epic's Tim Sweeney lays out the case for Unreal Engine 4". Gamasutra. UBM plc. Retrieved February 6, 2015.
- Schultz, Warren (2012). "Unreal Engine 4 - First Look. Epic is making some major development philosophy changes in UE4". About.com. IAC/InterActiveCorp. Retrieved February 6, 2015.
- Cifaldi, Frank (March 29, 2013). "Interview: Epic goes all-in on HTML5 with UE4 support". Gamasutra.
- Watts, Steve (March 29, 2013). "Unreal Engine 4 to support HTML 5, will be 'end of drivers'". Shacknews.
- "Unreal Engine 4 Leads on Next-Gen Mobile at SIGGRAPH". Nvidia. July 24, 2013.
- cinderboy (January 6, 2014). "Unreal Engine 4 – Next-gen running on Nvidia’s new mobile processor". MMO Culture.
- Chapple, Craig (March 29, 2013). "GDC 13: Unreal Engine 4 supports mobile and HTML5". develop-online.
- Takahashi, Dean (March 29, 2013). "Epic Games extends Unreal Engine 4 to mobile games, creates an eye-popping next-gen demo". VentureBeat.
- Sweeney, Tim (March 2, 2015). "If You Love Something Set It Free". Unreal Engine. Epic Games. Retrieved March 2, 2015.
- Houlihan, John (August 17, 2005). "Rein: "We've been working on Unreal Engine 4 for two years"". ComputerAndVideoGames.com. Future Publishing Limited. Archived from the original on January 10, 2014. Retrieved 2005-08-19.
- Valich, Theo (March 12, 2008). "Tim Sweeney, Part 3: Unreal Engine 4.0 aims at next-gen console war". TG Daily. Tigervision Media. Retrieved 2008-03-13.
- Brian Klug and Anand Lal Shimpi (January 6, 2014). "NVIDIA Tegra K1 Preview & Architecture Analysis". AnandTech. p. 3. Retrieved 2014-05-02.
- Kevin Parrish (February 11, 2012). "Epic Revealing Unreal Engine 4 Later This Year". Tom's Hardware. Retrieved 2012-03-01.
- Patrick Shaw (February 27, 2012). "Unreal Engine 4 Behind Closed Doors at GDC". Wired. Retrieved 2012-03-06.
- Samit Sarker (June 8, 2012). "Epic Games debuts Unreal Engine 4". Destructoid. Retrieved 2012-06-10.
- Casey Lynch (June 8, 2012). "Epic's Unreal Engine 4 'Elemental' Demo Lights Up the Uncanny Valley". IGN. Retrieved 2012-06-10.
- Woo-cheol, Jeong (July 12, 2012). "The future of game development is in UE4.". Thisisgame(Korea). Retrieved 2013-10-18.
- Andre Burnes (June 8, 2012). "Epic Reveals Stunning Elemental Demo, & Tim Sweeney On Unreal Engine 4". NVIDIA. Retrieved June 12, 2012.
- Samantha Earwood (March 21, 2014). "PS4: Epic Games’ Tim Sweeney Explains Lack Of Global Illumination In Unreal Engine 4". PSGang. Retrieved March 21, 2014.
- "Unreal Engine - Introduction to Blueprints". Retrieved April 17, 2015.
- Evangelho, Jason (May 22, 2014). "Why Is Epic Games Promoting Unreal Engine 4 With A 'Flappy Bird' Clone?". Forbes. Forbes, Inc. Retrieved February 8, 2015.
- Thier, Dave (June 29, 2012). "Epic's Tim Sweeney on How Unreal Engine 4 Will Change The Way Games Are Made, and Why You Care". Forbes. Retrieved October 4, 2014.
- Totilo, Stephen (June 8, 2012). "How Unreal Engine 4 Will Change The Next Games You Play". Kotaku.
- Dyer, Mitch (March 19, 2014). "GDC: Epic Games' Unreal Engine 4 adopts subscription model". IGN. Retrieved 2014-08-12.
- Haywald, Justin (March 19, 2014). "Epic opens up their Unreal development tools to everyone with a $19 subscription service". GameSpot. Retrieved August 12, 2014.
- McWhertor, Michael (March 19, 2014). "Epic Games making Unreal Engine 4 available for $19 per month, starting today". Polygon. Retrieved August 12, 2014.
- Batchelor, James (March 19, 2014). "Why Epic abandoned its 'outdated' model and offered everyone access to Unreal Engine 4. GDC 2014: Epic Games founder Tim Sweeney says even Minecraft players should benefit from the firm’s game-making tech". Polygon. Vox Media. Retrieved February 6, 2015.
- Tach, Dave (March 19, 2014). "Watch Epic's just-released Unreal Engine 4 in action". Polygon. Retrieved August 12, 2014.
- "Unreal Engine FAQ". Unreal Engine. Retrieved August 12, 2014.
- Waters, Deke (September 3, 2014). "Marketplace: Now Open For Business!". Unreal Engine Blog. Epic Games. Retrieved September 5, 2014.
- Connors, Devin (September 4, 2014). "Epic Games Opens Unreal Engine Marketplace to Developers". The Escapist. Retrieved September 5, 2014.
- Sheridan, Connor (September 4, 2014). "Epic launches Unreal Engine Marketplace". Computer and Video Games. Retrieved 2014-09-05.
- Batchelor, James (September 4, 2014). "Putting Unreal Engine in the classroom". Develop. Intent Media. Retrieved September 5, 2014.
- Matulef, Jeffrey (September 4, 2014). "Unreal Engine 4 is now free for educators". Eurogamer. Gamer Network. Retrieved 2014-09-05.
- Nutt, Christian (February 19, 2015). "Epic Games offers up $5 million in Unreal Dev Grants". Gamasutra. UBM plc. Retrieved March 11, 2015.
- Conditt, Jessica (February 19, 2015). "Epic Games is giving away $5 million to Unreal Engine 4 developers". Engadget. AOL. Retrieved March 19, 2015.
- Rad, Chloi (February 19, 2015). "Epic Games Wants To Give $5 Million In Grants To Unreal Engine Devs". IGN. Ziff Davis. Retrieved March 3, 2015.
- Sirani, Jordan (March 2, 2015). "Unreal Engine 4 is Free for Everyone". IGN. Ziff Davis. Retrieved March 12, 2015.
- Nutt, Christian (March 2, 2015). "Unreal Engine 4 is now free-to-download for everyone". Gamasutra. UBM plc. Retrieved March 12, 2015.
- Gaudiosi, John (March 3, 2015). "Why Epic Games is giving away its game technology". Fortune. Time Inc. Retrieved March 13, 2015.
- "UDN - Three - UnrealScriptReference". Udn.epicgames.com. Retrieved 2013-06-26.
- Thomsen, Mike (23 February 2010). "History of the Unreal Engine. The Epic evolution of gaming's most influential engine, from Gears of War to Mass Effect 2". IGN. Ziff Davis. Retrieved 3 January 2016.
- "Epic's Tim Sweeney lays out the case for Unreal Engine 4". Gamasutra. March 21, 2014. Retrieved 29 November 2015.
- "Academic Partners". Retrieved April 17, 2015.
- Batchelor, James (January 23, 2014). "Epic Games Centre opens at Staffordshire University". Develop. Intent Media. Retrieved March 28, 2015.
- "Epic Games and Applied Research associates' virtual heroes division launch Unreal Government network". ARA. March 2012.
- J. Hafer, T. (December 5, 2012). "Developer IPKeys licenses Unreal Engine 3 for military training simulations". PC Gamer. Future plc. Retrieved February 6, 2015.
- Develop magazine (February 14, 2008). "The Epic Diaries: February". Develop. Intent Media. Retrieved February 6, 2015.
- Cowley, Dana (October 16, 2012). "YEI Technology Debuts New Motion Capture and VR Techniques Using UDK". Unreal Engine. Epic Games. Retrieved February 6, 2015.
- Warner Bros (October 29, 2007). "HDFilms Partners With Epic Games To Power Upcoming 3D Animated Series "Chadam" With Unreal® Engine 3 For Studio 2.0, The Digital Production Division Of The Warner Bros. Television Group". Warner Bros. Entertainment Inc. Time Warner. Retrieved March 15, 2015.
- Cowley, Dana (October 25, 2012). "Just Cause Uses Unreal Engine 3 To Create "Persephone" Teaser Trailer". Unreal Engine. Epic Games. Retrieved March 15, 2015.
- Seymour, Mike (January 11, 2013). "House of Moves: in-house transmedia production". Fxguide. Retrieved March 15, 2015.
- Hart, Hugh (July 2, 2010). "Free Muvizu 3D Software Fuels DIY Animation". Wired. Condé Nast. Retrieved March 15, 2015.
- Gaudiosi, John (February 10, 2010). "Unreal Engine 3 Powers Critical And Commercial Success Lazytown". Unreal Engine. Epic Games. Retrieved March 15, 2015.
- Pitcher, Jenna (July 30, 2013). "Epic Games' Unreal Engine 3 licensed for US Army Research". Polygon. Vox Media. Retrieved February 6, 2015.
- Business Wire (July 29, 2013). "Intelligent Decisions Partners with Unreal Government Network. Epic Games’ award-winning Unreal Engine brings realistic, high fidelity environments to government training". Business Wire. Berkshire Hathaway. Retrieved March 17, 2015.
- "Air Force Certifies Use of the ARA Unreal Engine 3 Web Player". ARA. April 2013. Archived from the original on 23 July 2015.
- Gaudiosi, John (April 29, 2013). "Epic Games Powers US Air Force Training With Unreal Engine 3 Web Player From Virtual Heroes". Gamer Hub.
- Gaudiosi, John (26 January 2016). "NASA Is Using Unreal Engine 4 To Make Mars A Virtual Reality". Unreal Engine. Epic Games. Archived from the original on 28 January 2016. Retrieved 28 January 2016.
- "NASA Playing With Unreal Engine For Virtual World". Slashdot. Dice Holdings. November 22, 2006. Retrieved March 15, 2015.
- Collins, Hilton (November 22, 2013). "Video Game Puts the ‘Edge’ in First Responder Training". Government Technology. e.Republic. Retrieved February 6, 2015.
- Batchelor, James (July 1, 2014). "Develop 100: Unreal wins the battle of the engines". Develop. Intent Media. Retrieved June 28, 2015.
- "Most successful videogame engine". Guinness World Records.
- Keith Stuart (December 2009). The hidden story of the 3D engine - by the people who write them. How programming masters like Tim Sweeney built the engineering marvels of the 21st century.... The Guardian
- Mike Thomsen (February 2010). History of the Unreal Engine. The Epic evolution of gaming's most influential engine, from Gears Of War to Mass Effect 2. IGN
- John Gaudiosi (September 2011). Epic Games Founder Tim Sweeney Pushes Unreal Engine 3 Technology Forward. Forbes
- Stu Horvath (May 2012). The Imagination Engine: Why Next-Gen Videogames Will Rock Your World. Wired
- Dave Thier (June 2012). Epic's Tim Sweeney on How Unreal Engine 4 Will Change The Way Games Are Made, and Why You Care. Epic’s new engine could halve production costs, lower the prices of games, and spur détente between developers and consumers. Forbes
- Brian Steiner (June 2013). How The Unreal Engine Became A Real Gaming Powerhouse. Popular Mechanics
- GamesTM (September 2014). How Unreal Engine is changing for the new generation. GamesTM
- John Gaudiosi (March 2015). Why Epic Games is giving away its game technology. Fortune.
- Chris Plante (March 2015). Why video game engines may power the future of film and architecture. The original developer of Gears of War has an ambitious plan for the future of everything. The Verge.
- John P. Flynt & Chris Caviness (May 2006). UnrealScript Game Programming All in One. Thomson Course Technology. ISBN 978-1-598-63148-7
- Jason Busby, Zak Parrish & Jeff Wilson (July 2009). Mastering Unreal Technology, Volume I: Introduction to Level Design with Unreal Engine 3. Sams Publishing. ISBN 978-0-672-32991-3
- Jason Busby, Zak Parrish & Jeff Wilson (October 2009). Mastering Unreal Technology, Volume II: Advanced Level Design Concepts with Unreal Engine 3. Sams Publishing. ISBN 978-0-672-32992-0
- Ashish Amresh & Alex Okita (August 2010). Unreal Game Development. CRC Press. ISBN 978-1-568-81459-9
- Jason Busby, Zak Parrish & Jeff Wilson (January 2011). Mastering Unreal Technology, Volume III: Introduction to UnrealScript with Unreal Engine 3. Sams Publishing. ISBN 978-0-672-33082-7
- Richard J. Moore (August 2011). Unreal Development Kit 3: Beginner's Guide : a Fun, Quick, Step-by-step Guide to Level Design and Creating Your Own Game World. Packt Publishing. ISBN 978-1-849-69052-2
- Rachel Cordone (December 2011). Unreal Development Kit Game Programming with Unrealscript: Beginner's Guide. Packt Publishing. ISBN 978-1-849-69192-5
- Alan Thorn (December 2011). UDK Game Development. Cengage Learning, Inc.. ISBN 978-1-435-46018-8
- Thomas Mooney (February 2012). Unreal Development Kit Game Design Cookbook. Packt Publishing. ISBN 978-1-849-69180-2
- Robert Chin (April 2012). Beginning iOS 3D Unreal Games Development. Apress Media LLC. ISBN 978-1-430-24035-8
- Heinrich Hußmann (October 2012). "Realtime Interactive Architectural Visualization using Unreal Engine 3.5" (PDF). Ludwig-Maximilians-Universität München.
- John P. Doran (March 2013). Mastering UDK Game Development Hotshot. Packt Publishing. ISBN 978-1-849-69560-2
- Geof Sholler (August 2013). Build a Game with UDK. Packt Publishing. ISBN 978-1-849-69580-0
- Andrew Finch (March 2014). The Unreal Game Engine: A Comprehensive Guide to Creating Playable Levels. 3DTotal Publishing. ISBN 978-1-909-41404-4
- Ryan Shah (June 2014). Master the Art of Unreal Engine 4 - Blueprints. CreateSpace Independent Publishing. ISBN 978-1-500-21310-7
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