Unreal Engine

Unreal Engine

Developer(s)	Epic Games
Initial release	UE1: 1996 (1996) UE2: 2001 (2001) UE3: 2004 (2004) UE4: 2012 (2012)
Stable release	UE1: Build 613 / Dec 2000 UE2: Build 3369 / Nov 2005 UE3: Build 10907 / July 2013
Written in	UE1: C++ , UnrealScript, Assembly UE2: C++, UnrealScript UE3: C++, C#, UnrealScript, HLSL, GLSL, Cg, CUDA UE4: C++, HLSL, GLSL, Cg, CUDA
Operating system	Cross-platform
Available in	English
Type	Game engine
License	Proprietary; UDK free for noncommercial use[1][2]
Website	www.unrealengine.com

The Unreal Engine is a game engine developed by Epic Games, first illustrated 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.

The current release is Unreal Engine 3, designed for Microsoft's DirectX 9 (for Windows and Xbox 360), DirectX 10 (for Windows Vista) and DirectX 11 (for Windows 7 and later); OpenGL (for OS X, Linux, PlayStation 3, Wii U, and iOS), Android; Stage 3D (for Adobe Flash Player 11 and later); and JavaScript/WebGL (for HTML5).

Versions

Unreal Engine 1

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^[3] and a hardware-accelerated rendering path using the Glide API, specifically developed for 3dfx GPUs,^[4] and was updated for OpenGL and Direct3D. Large parts of the game were implemented in a custom scripting language called UnrealScript. The initial network performance was also very poor when compared to its biggest competitor, Quake II. Epic used this engine for both Unreal and Unreal Tournament. The release of Unreal Tournament marked great strides in both network performance and Direct3D and OpenGL support.^[5]

The engine became very popular due to the modular engine architecture and the inclusion of a scripting language, which made it easy to mod, including total conversions like Tactical Ops.^[6][7] For instance, a developer was able to replace the original renderer from UE1 with a DirectX 10 renderer in 2009.^[8]

Unreal Engine 2

Killing Floor is built on Unreal Engine 2

The second version made its debut in 2002 with America's Army. This generation saw the core code and rendering engine completely re-written. In addition, it featured UnrealEd 2, 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 said builds were stale and left behind, the last "official" build PS2 and GC saw was build 927 dated April 2002; last official UE2.5 build was build 3369. 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.^{[citation needed]}

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 featured optimizations specific to that console. EAX 3.0 is also supported for sound. Unreal Engine 2.X was build 2227, dated March 2004.

On March 24, 2011, Ubisoft Montreal revealed that UE2.5 was successfully running on the Nintendo 3DS.^[9]

Unreal Engine 3

The Ball is built on Unreal Engine 3.

The third and current generation of the Unreal Engine (UE3) is designed for DirectX (versions 9-11 for Windows and Xbox 360), as well as systems using OpenGL, including the PlayStation 3, OS X, iOS, Android, Stage 3D for Adobe Flash Player 11, JavaScript/WebGL for HTML5,^[10] PlayStation Vita, and Wii U.^[11] Its renderer supports many advanced techniques including HDRR, per-pixel lighting, and dynamic shadows. It also builds on the tools available in previous versions. 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.^[12]

In addition to the game industry, UE3 has also seen adoption by many non-gaming projects, for instance:

• 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.^[13]
• The animation software "Muvizu Play", which was released in April 2013, uses the UE3.^[14]
• In March 2012, the FBI licensed Epic's Unreal Development Kit to use in a simulator for training.

Unreal Engine 4

On August 18, 2005, Mark Rein, the vice-president of Epic Games, revealed that Unreal Engine 4 had been in development since 2003.^[15] Until mid-2008, development was exclusively done by Tim Sweeney, founder and technical director of Epic Games.^[16] The engine targets the eighth generation of PC hardware, consoles and NVIDIA Tegra K1-based Android devices announced in CES 2014.

In February 2012, Mark Rein said "people are going to be shocked later this year when they see Unreal Engine 4".^[17] Unreal Engine 4 was unveiled to limited attendees at the 2012 Game Developers Conference,^[18] and video of the engine being demonstrated by developer Alan "Talisman" Willard was released to the public on June 7, 2012 via GameTrailers TV.^[19][20] 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.^[21]

One of the major features of UE4 is real-time global illumination using voxel cone tracing, eliminating pre-computed lighting.^[22] UE4 also features new developer features to reduce iteration time and allow direct updating of C++ code. New features of the debugger for "Kismet" (a visual scripting engine that debuted in UE3) allow developers to directly visualize code while testing. The developer can then jump to the source code and edit it.^[23] Elements in the game can be clicked on directly to more easily change the game world. This also ultimately results in less of a divide between technical artist, a designer, and a programmer. The result is a reduced time to compile code and allows game creators to tweak settings in real time.^[24]

"[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."^[24]

Development

Unreal Engine 3

A comparison of Unreal Engine 1, 2, and 3's rendering capabilities using the Malcolm model from Unreal Tournament, Unreal Tournament 2004, and Unreal Tournament 3 side-by-side.

The first screenshots of Unreal Engine 3 were presented in 2004,^[25] at which point the engine was in development for 18 months already.^[26] 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. On the rendering side, Unreal Engine 3 also provided support for a gamma-correct high-dynamic range renderer. UE3 expected that content was authored in both high- and low-resolution version and baked normal maps for run-time; a major difference to previous generations where the game content was modeled directly (since normal mapping is a per-pixel operation and almost all the dynamic lighting in UE1 and 2 was calculated per-vertex using a Gouraud Shading technique)

The first released console game using Unreal Engine 3 was Gears of War. The first released PC game was RoboBlitz. 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.^[27]

Throughout the lifetime of the UE3, significant updates have been incorporated:

• Epic Games announced at Game Developers Conference (GDC) 2009 some improvements made to Unreal Engine 3. These included:^[28]
  • Unreal Lightmass: a global illumination solver. Provides high-quality static lighting with next-generation effects, such as soft shadows with accurate penumbrae, diffuse, specular inter-reflection, and color bleeding.
  • The ability to add fracture effects to static meshes to simulate destructible environments
  • Soft body dynamics (physics)
  • Large crowd simulation
• In December 2009, Epic demoed UE3 running on Apple's 3rd generation iPod Touch. They said that this will also support iPhone 3GS, and also an unknown mobile platform which has been revealed to be webOS at CES 2010.^[29] It has been revealed so far to be something on Nvidia's Tegra platform, and also Palm's webOS running PowerVR's SGX chip.
• In March 2010, Steamworks was integrated into the software, and is offered to licensees.^[30]
• In June 2010, Epic Games revealed Epic Citadel, a tech demo to showcase Unreal Engine 3 on iOS devices (iPhone, iPod touch, and iPad devices).
• In June 2010 during the Electronic Entertainment Expo 2010, Mark Rein (vice president of Epic Games) showcased a tech demo of Gears of War 2 in stereoscopic 3D running on an Xbox 360 thanks to the TriOviz for Games Technology. "This technology's great because it works on normal HD TVs, as well as the very high end 3DTVs," Rein commented to Computer and Video Games.^[31] "We're not planning to re-release this in 3D – unless Microsoft want us to – but I'm sure it's technology may be keen to put in the games developed by our partners."
• In October 2010, TriOviz for Games Technology has been officially integrated in Unreal Engine 3,^[32][33] allowing to easily convert in stereoscopic 3D, numerous past and upcoming games developed on Xbox 360 and PS3 with this engine.
• As of March 2011, the Unreal 3 Engine supports DirectX 11. Epic Games showcased it with a real-time demonstration video, entitled "Samaritan".^[34] Additions include tessellation and displacement mapping, advanced hair rendering with MSAA, deferred shading with MSAA, screen space subsurface scattering, image-based lighting, billboard reflections, glossy reflections, reflection shadows, point light reflections, and bokeh depth of field.^[35]
• In July 2011, Geomerics announced that their real-time global illumination solution^[36] Enlighten is now integrated with Unreal Engine 3 and available to licensees.^[37]
• In October 2011, Epic Games announced that a version of the engine would be compatible with Adobe Flash Player.^[38]
• In May 2012, UE3 added support for the RealD 3D stereoscopic technology.^[39]
• In March 2013, Mozilla and Epic Games have demonstrated UE3 running on the browser using HTML5 and JavaScript technologies.^[40]

Unreal Development Kit

Unmechanical was built with the 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. According to the current EULA, game developers can sell their games by paying Epic the cost of $99 USD, and 25% royalty on UDK related revenue above US$50,000 from all UDK-based games or commercial applications.^[41] The December 2010 UDK release added support for creating iOS games. As of the September 2011 release, iOS, OS X, and Windows platforms all support UDK-created games.

Games using the Unreal Engine

Other licensees

Unreal Engine 2

• Licensees of Education – The Art Institute of Pittsburgh
• Licensees of Construction Simulations and Interior Designs – Bentheim Interior Design

Unreal Engine 2 Runtime Custom License is used in many non-gaming projects including construction simulations and designs, training simulations, driving simulations, educations, virtual reality shopping malls, movie storyboards, continuities, pre-visuals, etc.

Until October 2007, more than 500 companies had Unreal Engine 2 Runtime Licenses.^{[citation needed]}

Unreal Engine 3

Licenses for education

Licenses for CG animation

See also

• Unreal, the original game featuring the engine
• UnrealScript, the scripting language used in Unreal Engine
• UnrealEd, the Unreal level editor
• Game engine
• List of game engines
• Video game development
• TriOviz for Games Technology

References

External links

Wikimedia Commons has media related to Unreal Engine 3.