IW (game engine)

IW engine

The lighting, shadow, and texture streaming of the engine can be seen in this screenshot, taken from the multiplayer mode of Call of Duty: Modern Warfare 2.
Developer(s)	Infinity Ward Treyarch Sledgehammer Games
Stable release	Black Ops III engine
Platform	Microsoft Windows, OS X, PlayStation 4, PlayStation 3, Xbox One, Xbox 360, Wii U, Wii
Type	Game engine
License	Proprietary

The IW engine is a game engine developed by Infinity Ward, Treyarch, and Sledgehammer Games for the Call of Duty series. The engine was originally based on id Tech 3 as its core, since the engine itself is proprietary with inclusion of GtkRadiant by id Software. It has been used by Infinity Ward, Treyarch, Raven Software, and Sledgehammer Games.

History

The engine has been distinct from the id Tech 3 engine on which it is based since Call of Duty 2 in 2005. The engine's name was not publicized until IGN was told at the E3 2009 by the studio that Call of Duty: Modern Warfare 2 would run on the "IW 4.0 engine". Development of the engine and the Call of Duty games has resulted in inclusion of advanced graphical features while maintaining an average of 60 frames per second on the consoles and PC.

Call of Duty 4: Modern Warfare was released using version 3.0 of the engine. This game included features such as bullet penetration, improved AI, lighting engine upgrades, particle system enhancements and many more improvements. Treyarch began using an enhanced version of the IW 3.0 engine for Call of Duty: World at War. Improvements were made to the physics model and dismemberment was added. Environments also featured more destructibility and could be set alight using the flamethrower. The flamethrower featured propagating fire and it was able to burn skin and clothes realistically. Treyarch modified the engine for their James Bond title, 007: Quantum of Solace.

Call of Duty: Modern Warfare 2 was released using the IW 4.0 engine, the only game to do so. The IW 4.0 engine featured texture streaming technology to create much higher environmental detail without sacrificing performance. Call of Duty: Black Ops was not based on IW 4.0; rather, Treyarch further enhanced the version of IW 3.0 they had used in their previous game. This version of the engine also featured streaming technology, lighting enhancements, and support for 3D imaging. Call of Duty: Modern Warfare 3 utilizes an improved version of the IW 4.0 engine. Improvements on the engine allow better streaming technology which allows larger regions for the game while running at a minimum of 60 frames per second. Further improvements to the audio and lighting engines have been made in this version.

Call of Duty: Black Ops II was developed using a further iteration of the IW engine. Texture blending has been improved due to a new technology called "reveal mapping" which compares tones between two textures and then blends them together. Also, there have been upgrades to the lighting engine which include HDR lighting, bounce lighting, self-shadowing, intersecting shadows and various other improvements. Call of Duty: Black Ops II takes advantage of DirectX 11 video cards on the Windows version of the game. The "zombie" mode has been moved to the multiplayer portion of the engine which will allow for much more variety within this part of the game. Black Ops II was released on November 13, 2012.

Call of Duty: Ghosts features an upgraded version of the IW 5.0 seen in Call of Duty: Modern Warfare 3. It is unknown at this time whether or not any engine features have been taken from Call of Duty: Black Ops II. Since the main developer is Infinity Ward they have returned to their original engine naming system and called this iteration IW6. IW6 is compatible with next-gen systems such as Xbox One and PlayStation 4 so polygon counts, texture detail and overall graphical fidelity has been increased. IW6 is also compatible with Microsoft Windows, Wii U, PS3 and Xbox 360. The IW6 engine features technology from Pixar, SubD, which increases the level of detail of models as one gets closer to them. Mark Rubin has said about the HDR lighting "We used to paint it in and cover up the cracks, but now it's all real-time". Ghosts uses Iris Adjust tech which allows the player to experience from a person's point of view how their eyes would react to changes in lighting conditions realistically. Other features include new animation systems, fluid dynamics, interactive smoke, displacement mapping and dynamic multiplayer maps. Ghosts was released on November 5, 2013. Call of Duty: Advanced Warfare features an unknown version of the IW engine, as the majority of it has been re-written. Advanced Warfare features a new audio engine built from the ground up. Developer Sledgehammer said they have incorporated brand new animation, physics, rendering, lighting, motion capture and facial animation systems.

Call of Duty: Black Ops III features an overhauled version of the Black Ops II engine, with the majority of the coding being re-written. New features include a completely new renderer and graphics engine, and the unification of Campaign, Multiplayer, and Zombies; which allows players to seamlessly swap between the three components of the game.

Games

	Engine name	Release year	Upgraded from	Change summary
Call of Duty	id Tech 3	2003	Modified version of id Tech 3 from Quake III Arena	DirectX 9 driven renderer (base id Tech 3 engine was OpenGL driven)
Call of Duty 2	IW 2.0	2005	Modified version of id Tech 3 from Call of Duty	Normal mapping Light bloom Heat haze Unified shadowing system Game console support.
Call of Duty 4: Modern Warfare	IW 3.0	2007	Call of Duty 2's IW 2.0 engine	Bullet penetration Improved AI Lighting engine upgrades Particle system enhancements Ragdoll physics integrated into character death animations. Self-shadow every frame
Call of Duty: World at War	IW 3.0	2008	Call of Duty 4: Modern Warfare's IW 3.0 engine	Audio occlusion Improved physics Ragdoll physics after death animations Dismemberment More destructible environments Realistic burning of skin and clothing Propagating fire
007: Quantum of Solace	IW 3.0	2008	Call of Duty 4: Modern Warfare's IW 3.0 engine	Cover system
Call of Duty: Modern Warfare 2	IW 4.0	2009	Call of Duty 4: Modern Warfare's IW 3.0 engine	Texture streaming technology Improved AI
Call of Duty: Black Ops	IW 3.0	2010	Call of Duty: World at War's IW 3.0 engine	Texture streaming technology Stereoscopic 3D support Deferred lighting
Call of Duty: Modern Warfare 3	IW 5.0 (MW3 engine)	2011	Call of Duty: Modern Warfare 2's IW 4.0 engine	Improvements to texture streaming technology to allow for larger regions Lighting engine enhancements to show reflections of some objects on tile floors Improvements to the audio engine
Call of Duty: Black Ops II	Black Ops II engine	2012	Call of Duty: Black Ops's IW 3.0 engine heavily modified	Reveal mapping (improved texture blending) Improved water effects Improved lighting effects Lens flare effects HDR lighting Bounce lighting Self-shadowing Intersecting shadows DirectX 11 for Windows version Improvements to the audio engine
Call of Duty: Ghosts	IW 6.0	2013	Call of Duty: Modern Warfare 3's MW3 engine updated (IW 5.0)	Pixar's SubD (models sub-divide the closer the player gets to them) New animation systems for movement (sliding, leaning etc.) Fluid dynamics Interactive smoke Improved AI Dynamic multiplayer maps Displacement mapping True real-time HDR lighting Iris Adjust tech Graphics Tessellation for Windows, PlayStation 4 and Xbox One PhysX support for Windows version Specular mapping on particle effects Using Umbra's advanced rendering technology
Call of Duty: Black Ops III	Black Ops III engine	2015	Call of Duty: Black Ops II's Black Ops II engine updated	Renderer Animation systems Lightning Dynamic water simulation system