Unreal Engine 5.5: discover 10 key features for CG artists
Epic Games has released Unreal Engine 5.5, the latest major version of the game engine and real-time renderer.
Even by Epic Games’ standards, it’s a major update, with the release notes divided up into over 100 sections, many covering multiple individual features.
The changes span every major toolset, including level design, coding and audio, but below, you can read our pick of the 10 key features for CG artists, as opposed to programmers.
They range from headline changes like the MegaLights toolset to new character rigging and animation tools, by way of hidden gems like the Day Sequence plugin and Color Grading Panel.
1. MegaLights: use hundreds of dynamic lights in real-time scenes (Experimental)
Undoubtedly the most talked-about feature in Unreal Engine 5.5 – although one still some way off being production-ready – is the new MegaLights system.
Billed as the ‘Nanite of lights’, it aims to do for lighting what the virtualized geometry system did for asset creation, enabling artists to work without having to think about in-engine performance.
According to Epic, MegaLights makes it possible to use “orders of magnitudes” more lights than before and still maintain real-time performance: the demo above shows a scene with over a thousand shadow-casting lights running on a PlayStation 5.
It provides an alternate direct lighting path, replacing shadow maps and ray traced shadows.
Unlike standard deferred shading, in which lighting quality remains constant but processing cost increases with the number of lights, MegaLights have constant performance, but visual quality decreases with light count.
The system uses ray tracing by default, and supports area lights as well as point and spot lights.
2. Light Function Atlas: bake expensive animated light functions to 2D textures
Another performance-enhancing lighting feature in Unreal Engine 5 is the Light Function Atlas.
It bakes computationally expensive animated Light Functions into 2D textures that are projected onto the scene at runtime, reducing processing overhead.
Although it has some limitations, particularly with Directional and Rect lights, it makes it feasible to use chromatic light functions in production.
And while it has had less attention than the MegaLights system, the Light Function Atlas can be used with it, making it possible to use light functions with MegaLights.
3. Control Rig: author animatable deformers and assign them to characters in Sequencer
Unreal Engine 5.5 also features some major updates to rigging and animation workflow, including the option to author animatable animation deformers inside Control Rig.
The deformers can then be applied to characters inside the Sequencer animation editor.
An accompanying Animator Kit plugin provides a library of readymade Control Rigs with built-in deformers – including Lattice and Sculpt – that can be used as a base for custom rigs.
Suggested uses include contact deformation and squash-and-stretch effects, as shown above.
4. Modular Control Rig and Chaos Modular Vehicles (Beta/Experimental)
The Modular Control Rig introduced in Unreal Engine 5.4 moves into beta in the latest release, and gets a number of feature and workflow improvements.
They include new sets of modules for creating rigs for quadruped characters and vehicles as well as bipeds.
We’re focusing on the latter here, since Unreal Engine 5.5 includes another related new feature, the Chaos Modular Vehicles system, an experimental new vehicle simulation plugin.
It enables vehicles, including cars, trucks and planes, to be built – or destroyed – at runtime.
Unlike the existing Chaos Vehicle plugin, which requires a single, fixed skeletal mesh topology, vehicles can be built from sets of components, each with its own simulation set-up.
5. Sequencer: control animations with non-destructive animation layers
Sequencer gets a lot of usability improvements in Unreal Engine 5.5, but arguably the most important change is support for animation layers.
The new workflow provides a level of control over animations typically only found in offline animation tools, dividing motion into independent layers that can be edited non-destructively.
As well as adding, removing or muting layers, animators can set layers to have an additive or override effect, merge multiple layers into one, or assign animatable weights to individual layers.
6. MetaHuman Animator: generate facial animation from audio files (Experimental)
Another new animation feature – albeit one outside the core application – is support for audio-driven facial animation in MetaHuman Animator.
Part of Epic Games’ free MetaHuman plugin, it streamlines the process of transferring facial motion from video footage to a MetaHuman character inside Unreal Engine.
The new Audio Driven Animation feature provides an alternative workflow, using an audio file instead of video to generate facial animation.
As well as automatically lip-sycing a character to recorded dialogue, MetaHuman Animator infers the movement of the upper face, resulting in more believable facial animation.
It works with “various voices and languages”, and runs entirely on the user’s local machine.
7. Mutable: generate character variations and runtime (Beta)
Another interesting plugin that gets an update in Unreal Engine 5.5 is Mutable.
Although the tool, created by third-party developer Anticto, has shipped with Unreal Engine since version 5.1, it moves into beta in the current release.
It enables users to generate variants of assets – primarily characters, but also creatures, props or weapons – procedurally, varying their skeletal meshes, materials and textures.
For characters, a key benefit is Mutable’s ability to handle layered clothing, using hidden surface removal and mesh and texture merging to prevent intersections and improve performance.
8. Day Sequence: automatically generate in-game lighting cycles (Experimental)
Lighting artists also get an experimental new plugin, Day Sequence, which automatically generates an in-game 24-hour lighting cycle.
Its individual components – the sun, moon, stars, atmosphere and clouds – can be adjusted inside Sequencer.
As well as automating most of the work needed to create a basic day/night cycle, the plugin handles network synchronization, providing multiplayer support and POI creation out of the box.
9. NFOR Denoiser: temporally stable denoising in the Path Tracer (Experimental)
Although the Path Tracer, Unreal Engine’s hardware-accelerated ray tracing render mode, officially becomes production-ready in Unreal Engine 5.5, it also gets experimental new features.
One is the NFOR (Nonlinearly Weighted First Order Regression) Denoiser – or more prosaically, the Spatio-Temporal Denoiser – for denoising rendered animations.
It denoises each pixel in a frame based on surrounding patches in both time and space to produce more temporally stable results.
It’s intended for high-quality offline rendering via the Movie Render Queue, such as architectural visualization, and isn’t suited for shots with fast-moving objects.
10. Color Grading Panel: better grading for all offline renders, not just virtual production
For offline rendering, another small-but-significant change in Unreal Engine 5.5 is that the Color Grading Panel is now available for general use, not just for virtual production.
Originally part of the In-Camera VFX Editor (ICVFX Editor), it provides a “rich, artist-friendly interface for creative color manipulation”.
It is now available in the general Unreal Editor, and now also supports post-process volumes and color correction regions.
Just some of 100+ new features in Unreal Engine 5.5
The 10 features listed here only scratch the surface of the changes in Unreal Engine 5.
Among the artist tools, there are particularly extensive changes to the new motion design toolset introduced in Unreal Engine 5.4, and to the virtual production tools.
There are also significant updates to in-editor modeling and texturing, to simulation and VFX, and to procedural content generation. You can find a full changelog via the links below.
System requirements and availability
Unreal Engine 5.5 is available for 64-bit Windows, macOS and Linux.
For non-interactive content, the software is free to users with revenue under $1 million/year. For larger studios, subscriptions cost $1,850/seat/year, including Twinmotion and RealityCapture.
For games developed with the engine, Epic takes 5% of the gross royalties after the first $1 million generated.
Read an overview of the new features in Unreal Engine 5.5 on Epic Games’ blog
Read a full list of new features in Unreal Engine 5.5 in the online release notes
Have your say on this story by following CG Channel on Facebook, Instagram and X (formerly Twitter). As well as being able to comment on stories, followers of our social media accounts can see videos we don’t post on the site itself, including making-ofs for the latest VFX movies, animations, games cinematics and motion graphics projects.