Unreal Engine 5

Unreal Engine 5 (UE5) is the latest version of Unreal Engine developed by Epic Games. It was revealed in May 2020 and officially released in April 2022. Major features of Unreal Engine 5 include Nanite, a virtualized geometry system that allows game developers to use arbitrarily high quality meshes with automatically generated Level of detail, and Lumen, a dynamic global illumination and reflections system that uses software and hardware ray tracing.

History


Unreal Engine 5 was revealed on May 13, 2020, supporting all existing systems supported by Unreal Engine 4, including the next-generation consoles PlayStation 5 and Xbox Series X/S. Work on the engine started about two years prior to its announcement. It was released in early access on May 26, 2021, and formally launched for developers on April 5, 2022.

Epic had worked closely with Sony in optimizing Unreal Engine 5 for the PlayStation 5, with Epic collaborating with Sony on the console's storage architecture. To demonstrate the ease of creating a detailed world with minimal effort, the May 2020 reveal of the engine showcased a demo called "Lumen in the Land of Nanite" running on a PlayStation 5 that was built mostly by pulling assets from the Quixel library and using the Nanite, Lumen, and other Unreal Engine 5 components to create a photorealistic cave setting that could be explored. Epic affirmed that Unreal Engine 5 would be fully supported on the Xbox Series X as well, but had been focused on the PlayStation 5 during the announcement as a result of their work with Sony in the years prior.

Epic has used its game Fortnite as a testbed for Unreal Engine 5 to showcase what the engine can do to the industry, with the game brought to use Unreal Engine 5 in December 2021. Fortnite's Battle Royale mode received visual improvements via Unreal Engine 5.1 with the launch of Chapter 4 on December 4, 2022. The Matrix Awakens, a tie-in experience ahead of the release of The Matrix Resurrections, was developed by Epic to be a further demonstration of Unreal Engine 5 along with other technology that they had acquired over 2020 and 2021, including their MetaHuman Creator developed and integrated into Unreal Engine 5 with technology from 3Lateral, Cubic Motion, and Quixel.

In March 2024, Epic Games launched Project Titan, a collaborative art jam to create a free open world sample project for Unreal Engine.

Nanite
One of UE5's major features is Nanite, an engine that allows for high-detailed photographic source material to be imported into games. The goal of Unreal Engine 5 was to make it as easy as possible for developers to create detailed game worlds without having to spend excessive time on creating new detailed assets. Nanite can import nearly any other pre-existing three-dimension representation of objects and environments, including ZBrush and CAD models, enabling the use of film-quality assets. Nanite automatically handles the levels of detail (LODs) of these imported objects appropriate to the target platform and draw distance, a task that an artist would have had to perform manually otherwise by creating a new model for each LoD and creating normal maps for details. Unlike traditional LoD, Nanite can use different levels of detail within a single asset. According to a talk by Epic Games' Brian Karis at SIGGRAPH 2021, Part of the research done to create Nanite was to find a method that could stitch the edges of different levels of detail together such that there are no "cracks" between them at the boundaries when they are of the same asset. In its initial release, Nanite could only be used for static meshes.

With potentially tens of billions of polygons present on a single screen at 4K resolution, Epic also developed the Unreal Engine 5 to take advantage of the upcoming high-speed storage solutions with the next-generation console hardware that will use a mix of RAM and custom solid-state drives. According to Epic Games founder Tim Sweeney, With UE5's new loading system "you can bring in [a game's] geometry and display it despite it not all fitting in memory." UE5 scales the amount of detail in the geometry used to the speed of the device's storage if the device's storage is too slow to load the ideal amount.

Lumen
Lumen is another component described as a "fully dynamic global illumination solution that immediately reacts to scene and light changes". Lumen eliminates the need for artists and developers to craft a lightmap for a given scene, but instead calculates light reflections and shadows on the fly, thus allowing for real-time behavior of light sources. It also allows for faster development cycles for game designers as they do not need to wait for the lightmaps to be computed. Lumen can use either software or hardware ray tracing, with the software version being more widely supported by devices at the expense of lower fidelity such as in reflections or water. It can be turned off with a fallback to Singed Distance Field Ambient Occlusion.

Additional Features
Virtual Shadow Maps is another component added in Unreal Engine 5 described as "a new shadow mapping method used to deliver consistent, high-resolution shadowing that works with film-quality assets and large, dynamically lit open worlds". Virtual Shadow Maps differs from the common shadow map implementation in its extremely high resolution, more detailed shadows, and the lack of shadows popping in and out which can be found in the more common shadow maps technique due to shadow cascades.

UE5 uses Niagara for fluid and particle dynamics and it's own Chaos physics engine in place of PhysX.

Additional features planned for Unreal Engine 5 come from Epic's acquisitions and partnerships. The Nanite virtualized geometry technology allows Epic to take advantage of its past acquisition of Quixel, the world's largest photogrammetry library as of 2019. The MetaHuman Creator is a project based on technology from three companies acquired by Epic—3Lateral, Cubic Motion, and Quixel—to allow developers to quickly create realistic human characters that can then be exported for use within Unreal. Through partnership with Cesium, Epic plans to offer a free plugin to provide 3D geospatial data for Unreal users, allowing them to recreate any part of the mapped surface of Earth. Epic will include RealityCapture, a product it acquired with its acquisition of Capturing Reality that can generate 3D models of any object from a collection of photographs taken of it from multiple angles, and the various middleware tools offered by Epic Games Tools.

Licensing
Unreal Engine 5 retains the royalty model started with Unreal Engine 4, with developers returning 5% of gross revenues to Epic Games, although this fee is waived for sales made through the Epic Games Store. Further, Epic announced alongside Unreal Engine 5 that they will not take any fee from games using any version of Unreal Engine for the first US$1 million in gross revenue, retroactive to January 1, 2020. Epic unveiled per-seat licensing of the Unreal Engine, starting in April 2024, for its runtime use with non-gaming applications such as in film and television production if their revenues exceed $1 million, with each seat costing $1850/year.