View source for StarCitizen:Star Engine

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[[File:Star Engine Logo.png|thumb|Star Engine Logo]]'''Star Engine''' is the video game engine used by [[StarCitizen:Star Citizen|''Star Citizen'']] and [[StarCitizen:Squadron 42|''Squadron 42'']].

Star Engine aims among others to be seamless without any loading screens or invisible walls despite being massively multiplayer.<ref name=":0">[https://www.youtube.com/watch?v=xKWa4WoTkV4 CitizenCon 2953: Shaping the ‘Verse - The Future of StarEngine], Star Citizen, YouTube, 24 oct. 2023</ref>

== Development ==
Star Engine is a heavily refactored version of [https://www.cryengine.com/ CryEngine 3] from [[StarCitizen:Crytek]] used since the first [https://www.youtube.com/watch?v=WpgUuGunU0o in-engine video] released at the start of the [[StarCitizen:Crowdfunding campaign]]. More specifically, the last CryEngine update integrated into Star Citizen's code was patch 3.8.<ref name="GN-20160930-ST_64bitEngine">[http://www.gamersnexus.net/gg/2622-star-citizen-sean-tracy-64bit-engine-tech-edge-blending Gamers Nexus - Interview with Sean Tracy, summary]</ref> This heavily modified version has been internally named Star Engine since September 2016 at the latest, before moving to [[StarCitizen:Amazon Lumberyard]].<ref name="GN-20160924-CR CitCon16">[https://web.archive.org/web/20160925135611/https://gamersnexus.net/gg/2613-chris-roberts-on-star-citizen-procedural-planets-alpha3-citizencon Gamers Nexus - Interview with Chris Roberts, summary, gamersnexus.net, September 24, 2016, archived.]</ref> 

On 2016-12-23, CIG announced with the release of [[Update:Star Citizen Alpha 2.6.0|Star Citizen Alpha 2.6.0]] its move to Amazon Lumberyard game-engine, which is also based on CryEngine 3.8,<ref>[[StarCitizen:Erin Roberts]]: "Lumberyard is completely based on Cryengine", wccftech, [https://wccftech.com/star-citizen-switches-engines/ Star Citizen Switches Engines: Move Along Folks, Nothing to See Here], Dec 24, 2016</ref> in order to utilize the integrated Amazon Web Services (AWS) and Cloud-Computing features "to support next generation online gaming"<ref>[https://us5.campaign-archive.com/?u=32d8ef31243db6075c45571bd&id=d92114e762&e=440f62ae8a Star Citizen Newsletter - Alpha 2.6 with Star Marine!], December 23rd, 2016</ref>{{RSIForumDiscussion|ref=yes|discnum=364217|text=Clarification by Chris Roberts on the switch to Lumberyard}}. It is not known which version of Lumberyard is currently integrated in Star Engine and how CIG will handle future iterations (as of November 2016, the current version of Lumberyard is ''Beta 1.6'').

The StarEngine development and support is driven internally within [[StarCitizen:Cloud Imperium|Cloud Imperium Games]] with some of former Crytek employees supervising the project.<ref name="GN-20160930-ST_64bitEngine" /> A lot of the work on it is done in the Frankfurt studio.<ref>[https://www.lebetatesteur.ca/cloud-imperium-games-dans-les-coulisses-de-star-citizen/ Cloud Imperium Games – Behind the Scenes of Star Citizen], lebetatesteur.ca, September 5, 2025</ref>

== Features ==
{{Editorial Note|Although CIG is very open about their development process, not all details on internal processes and work on the engine are released to the public. The following list contains features that are described in interviews, Monthly Reports or dev comments. The names can differ from the actual name internally used and the feature funtionality should always be considered as not fully accurate. Additionally, some are already integrated CryEngine 3.8 and/or Lumberyard features - for a list see {{WP|ref=no|CryEngine}}}}
Here's a list of features added by CIG since CryEngine 3.8.

=== Notable Tech ===
*[[StarCitizen:Large World]] (64bit world space coordinates)
*[[StarCitizen:Object Container Streaming]]
*[[StarCitizen:Mega Map]]
*[[StarCitizen:Zone System]]
*[[StarCitizen:Local Physics Grids]]
*[[StarCitizen:Room System]]
*[[StarCitizen:Camera Relative Rendering]]<ref name="MR-201409" />
*[[StarCitizen:Prodecural Planets|Procedurally Generated Planets]]
*[[StarCitizen:PBR]] (Physically Based Rendering)
*The Sun as a physical object (possibility of Binary Star Systems or exploding ships in orbit casting light to the planet surface)<ref name="GN-20160924-CR_CitCon16">[https://web.archive.org/web/20230827094414/http://www.gamersnexus.net/gg/2613-chris-roberts-on-star-citizen-procedural-planets-alpha3-citizencon Chris Roberts on Star Citizen's Procedural Planets, Alpha 3.0, & CitizenCon] on gamersnexus.net (2016-09-24), archived on web.archive.org (2023-08-27)</ref>
*[[StarCitizen:StarScript]]<ref>[https://youtu.be/lPaDb5rh0tE Star Citizen Live | Tech Talk w/ Benoit Beausejour], YouTube, retrieved 2025-09-12.</ref> (formerly Subsumption AI<ref name="Mr-201410">[https://robertsspaceindustries.com/comm-link/transmission/14191-Monthly-Report-September-2014 Monthly Report Sept 2014]</ref>)
*[[StarCitizen:Unified First- & Third-Person animations]]
*[[StarCitizen:Unique Global Entity ID]]<ref name="MR-201411">[https://robertsspaceindustries.com/comm-link/transmission/14345-Monthly-Report-November Monthly Report Nov 2014]</ref>
*Generic Instance Manager<ref name="MR-201504">[https://robertsspaceindustries.com/comm-link/transmission/14690-Monthly-Report Monthly Report April 2015]</ref>
*Universe Simulator<ref name="MR-201504" />
*Persistence (Player Info Server, Presence Server, HUB Server and Player Persistence)<ref name="MR-201504" />
*[[StarCitizen:Item Port System]]<ref name="MR-201505">[https://robertsspaceindustries.com/comm-link/transmission/14758-Monthly-Report Monthly Report May 2015]</ref>
*[[StarCitizen:StarNetwork]]
*GOST (Game Object State) (reworked to newer system<ref name="MR-201409">[https://robertsspaceindustries.com/comm-link/transmission/14278-Monthly-Report-October-2014 Monthly Report Oct 2014]</ref>)
*"Grabby Hands" - now integrated into the Cargo system and Loot system,<ref name="MR-201504" /><ref>[http://imperialnews.network/2016/09/september-subscriber-town-hall-summary/ Subscriber's Town Hall with Austin Developers]</ref> initial system for grabbing and moving objects (e.g. cargo) and initially set to be released in the (later delayed) [[StarCitizen:Astro Arena]] or [[StarCitizen:SATABall]] FPS game mode
*Multi-LayerBlend - character shader tech<ref name="Mr-201406">[https://robertsspaceindustries.com/comm-link/transmission/14814-Monthly-Report Monthly Report June 2015]</ref>
*iPredictor (movement prediction) system<ref name="MR-201504" />
*Diffusion (cloud-oriented back-end service architecture)

=== Rendering ===
{{List item
|Object space shader damage
|Allows 4 different types of damage to be permanently inflicted on ships, including cutting holes, and blended seamlessly into the base shading.
}}
{{List item
|Real time environment-probe capture and compression
|Avoids needing to bake probes in space and on planets.
}}
{{List item
|Image based lens flares 
|Use entire source image to simulate 4 different physically based lens distortions per color channel on up to 20 individual elements
}}
{{List item
|Physically based bloom
|Wide exponential kernel based purely on light intensity.
}}
{{List item
|Human eye exposure simulation 
|Capture histogram of light intensity from both screen and surroundings, isolate range of light we intend to focus on, simulate both pupil and photo-pigment reactions for quick and slow reactions.
}}
{{List item
|Major improvements to planar lights
|Far more physical basis now which results in major quality improvements.
}}
{{List item
|Intelligent mesh-merging system
|Repeatedly searches for best bang-for-buck mesh merge opportunity in a scene until we hit a memory limit.
}}
{{List item
|Upgraded volumetric fog
|E.g.: support for planar lights, light-boxes, enviroment-probe priority sorting.
}}
{{List item
|Major upgrade to shadow pool system
|All lights share one giant pool for better dynamic resolution scaling, shadows can be cached between frames for better performance.
}}
{{List item
|Render target pooling
|Shares memory between internal textures used in the renderer to vastly reduce VRAM usage.
}}
{{List item
|Render to texture pipeline
|Ability to render secondary viewports with full or limited feature set to then be used as textures in the primary scene, e.g.: video comms or holograms.
}}
{{List item
|Tiled lighting upgrades
|Use rasterization light culling for greater efficiency, particle support.
}}
{{List item
|Density based LOD algorithm
|LODs change based on polygon density to ensure consistent appearance, less artist intervention, and promote more optimal art assets with fewer sub-pixel polygons.
}}
{{List item
|GGX normal map filtering 
|gloss adjusted in mip-chain to best fit of our GGX lighting model to give the same results as super sampled normals.
}}
{{List item
|Camera relative rendering 
|Allows 64-bit world without incurring any rendering performance hit by maintaining 32-bit precision for rendering.
}}
{{List item
|GPU Particle System
|Built from the ground up for efficiency, distinct from Lumberyards and CryEngine's GPU particle systems.
}}
{{List item
|Various improvements to transparency sorting
|Generalized system, allow depth of field and motion blur to not effect nearby in-focus objects, order independent transparency for specific shaders such as hair.
}}
{{List item
|Artist friendly profiler
|Captures statistics per art-team, and per area of the level allowing accurate breakdowns and quick diagnosing of performance issues.
}}
{{List item
|Physically based atmospheric scattering
|
}}
{{List item
|Hierarchical object management
|Efficient searches and culling, local coordinate frames for things like ships inside ships on planets which are rotating etc.<ref>{{Cite RSI|url=spectrum/community/SC/forum/50259/thread/engine-question/250379|text=Ali Brown comments on Star Engine renderer on Spectrum}}</ref>
}}
{{List item
|[[StarCitizen:HDR support|High Dynamic Range]]
|
}}

==== Tech included in [[StarCitizen:Star Citizen Alpha 3.0.0]]<ref name="CitizenCon 2017">CitizenCon 2017 Graphics Engineering Panel "Beyond the Cutting Edge"</ref> ====

*P4K System - improved data handling system
*Planetary Rotation
*Temporal Supersampling (TSAA) - previously rendered frames are used to improve the anti-aliasing results on the new frame
*Improved Screen Space Directional Occlusion (SSDO)
*New Filmic Tone Mapping Curve (ACES)
*PBR Glass - Glass (e.g. cockpits) can be rendered with phyiscs-based distortions, cracks, reflections and chromatic effects

=== Planned features (as of October 2017)<ref name="CitizenCon 2017" /> ===

'''Short term'''

*Terrain Occlusion & Shadowing
* Gameplay Driven Material Shaders
*"Space Fog" (Gas Clouds in e.g. asteroid fields)
*Improved Hair
*New Shield Effect
*Depth of Field Improvements
*Colour Processing Improvements
*New Motion Blur Implementation
*Support for Complex Shading Models

'''Mid/Long term goals'''

* Object Container Streaming support on the low level/system side
*Improved Planet Effects (shadows, clouds, etc.)
*Improved Space Effects (stars, sun, rings, etc.)
*Dynamic [[StarCitizen:Global Illumination]]
*Batching of physics-thread
*Batching of render-thread
*Vulcan backend support

=== Planned features (as of October 2023) ===

*Cloud light shafts - 3D volumetric shadows from clouds as opposed to post effect<ref name=":0" />
*Ground fog - follows the terrain, fully integrated into the atmosphere, reduces the scattered light<ref name=":0" />
*New water - constantly in motion, reactive to wind and objects, be it fottprints in puddles, rivers, lakes, oceans or hot tubs<ref name=":0" />
*Fully dynamic blood, sweat and tears<ref name=":0" />
*Temporal Upscaling<ref name=":0" />
*Virtual Terrain Texturing<ref name=":0" />
*Improved Scattering System<ref name=":0" />
*Ray Traced Global Ilumination<ref name=":0" />
*[[StarCitizen:Starcloth]]<ref name=":0" />
*[[StarCitizen:Starhair]]<ref name=":0" />
*[[StarCitizen:Maelstrom (destruction system)|Maelstrom]] - physically based destruction system.

== Tools & 3rd-Party Software ==

*Kythera - AI middleware<ref name="SC kythera">[http://kythera.ai/case-studies/star-citizen ''Kythera'' by Moon Collider]</ref>
*[[StarCitizen:Vulkan|Vulkan API]] - 3D graphics and compute API {{RSIForumComment|ref=yes|comnum=7581676|text=Ali Brown (Director of Graphics Engineering) comment about Vulkan}}
*Wwise - Sound Engine {{WP|Wwise}}
*FMOD - (deprecated) Sound Engine <ref name="MR-201409" />
*DataForge {{fact}} - Data management, Ship & Weapons balancing<ref name="MR-201409" />
*StoryForge - Dialogue and Conversations system, built upon DataForge<ref name="MR-201411" />
*VERS 3D (formerly known as PlanetEd) - Editor for creating planets<ref>[https://youtu.be/fDROliuDczo?t=659 PlanetEd reference]</ref>
*System Layout Tool - Star system layout and design<ref name="Mr-201410" />
*Room Management System - (deprecated) System for players to manage their hangars; now changed and integrated in Item Port System<ref name="MR-201409" />

== Licensing ==
Star Engine is not available for sale nor licensing, in part for legal reasons related to existing agreements.<ref name=":1">[https://www.youtube.com/watch?v=GWFC4TXOOv0 Quantum Vegas 2955: Session 1: "Tech & Tools" with Sean Tracy], Quantum Vegas 2955, Youtube, 21 July 2025</ref><ref>[https://m.twitch.tv/clip/RamshackleObedientPieKAPOW-2rDuBajYtONFEIh0 CitizenCon 2953 interview with Brian Chambers], Hugo Lisoir, Twitch, 22 Oct 2023</ref> [[StarCitizen:Sean Tracy]] who has done that job at [[StarCitizen:Crytek]] for a number of years said that this would require a 100% support a 100% of the timeand he therefore hopes this won't happen at CIG and would oppose it as the game itself would massively suffer.<ref name=":1" />

== Trivia == 

*A typical Star Engine frame update has up to 64 hardware threads, 200 software threads, over 700 000 streamed-in entities on a server, millions of entities overall in the solar system, about 150 000 component updates.<ref name=":0" />
*Any given frame has over 200 vehicles, thousands of actors, including new creatures, over 2 000 000 physical objects, over 100 000 objects generated per frame, many unique locations to explore in a gigantic seamless space.<ref name=":0" />

==List of Videos on the Star Engine==
*[https://www.youtube.com/watch?v=WpgUuGunU0o Squadron 42 Trailer (2012)]
*[https://youtu.be/kGZJP5oVUn8 Gamers Nexus - Video Interview with Chris Roberts on Procedural Generation (2014)]
*[https://youtu.be/kO9dEq3YMWc Gamers Nexus - Video Interview with Chris Roberts on Engine Architecture & Zoning Optimization (2015)]
*[https://youtu.be/j0r6aOasFEQ Gamers Nexus - Video Interview with Chris Roberts on Instancing & Player Counts (2015)]
*[https://youtu.be/XD9_L5o4mhQ Chris Roberts on DX12 & Vulkan support (2015)]
*[https://youtu.be/TbWh5inW7Fw Gamers Nexus - Video Interview with Chris Roberts on Character Tech, Weather System, & Engine Architecture (2016)]
*[https://youtu.be/k_jq_dCW6Jc Gamers Nexus - Video Interview with Sean Tracy on CPU thread management, Jobs System, Character Technology, Lighting, sun/planet movement, Authoring Tools & AI (2016)]
*[https://www.youtube.com/watch?v=_TlLNCyVudc Gamers Nexus - Video Interview with Sean Tracy on Parallax Occlusion Mapping for Biomes edge-blending; Spring Tension and Inverse Kinematics for the Rover & Ships (2016)]
*[https://www.youtube.com/watch?v=fDROliuDczo Gamers Nexus - Video Interview with Chris Roberts on Procedural Planets V2 (2016)]
*[https://youtu.be/OB_AI9ukSp8 Gamers Nexus - Video Interview with Sean Tracy on 64-bit Engine Tech & Procedural Edge Blending (2016)]
*[https://www.youtube.com/watch?v=ahGLguBQBQ8 Gamers Nexus - CitizenCon 2016 PlanetEd tool (2016)]
*[https://www.youtube.com/watch?v=xKWa4WoTkV4 CitizenCon 2953: Shaping the ‘Verse - The Future of StarEngine (2023)]
*[https://https://www.youtube.com/watch?v=y_QE4qig9sw Star Citizen Live: Q&A StarEngine (2024)]

== See also ==
*{{Link RSI|url=https://robertsspaceindustries.com/spectrum/community/SC/forum/50259/thread/cryengine-vs-starengine/3135119|text=Clive Johnson's comment on Star Engine modifications on top of CryEngine/Lumberyard}}

== References ==
<references />

{{Short description|Game engine that powers Star Citizen}}

[[Category:Development]]
[[Category:Video game engines]]
[[Category:StarNamed]]