A Deep Dive Into Unreal Engine 5.5's New Animation Tools

Epic Games' Fredrik Nilsson has joined us to discuss Unreal Engine 5.5 and provide a comprehensive overview of the new animation tools the latest release has introduced.

Please share a few words about yourselves and how you joined Epic Games.

My name is Fredrik Nilsson. I’m a Technical Product Management Director focused on Animation Authoring tools inside Unreal Engine.

I joined Epic Games almost three years ago to push the limits of our Unreal Engine animation tools. I’ve been in animation most of my career, but I hadn’t used Unreal Engine as an animation tool until I applied for the job at Epic. I’ve animated with many tools throughout my career, and Unreal is at the point now, for me, that I don’t want to animate anywhere else.

One of my favorite projects that I’ve worked on at Epic was animating this super cool dragon for a UEFN island called Forest Guardian, built by some of Epic’s incredible artists. This was a great testbed for rigging and animating characters directly in UEFN.

I was also asked to help animate a UEFN robot encounter demo that was showcased at GDC, which was a really fun project with an incredible team. This robot was actually rigged and fully animated directly in UEFN.

UEFN was released around the same time we released version 5.2 of Unreal in May of 2023. Since then, I’ve moved fully into product management for our Animation Authoring tools, and work closely with our engineers, our UX design team, other product managers, and of course all of the artists who use the tools.

Does shipping Unreal Engine Previews help Epic Games refine the final releases? How do you work with feedback?

Shipping early preview builds definitely helps us with the product. We try to push on the tools and test them as much as we can with our internal projects and our workflows before they’re released to developers.

After they’re released, the product team always collects feedback from as many people as possible, which helps us prioritize what to work on next. We also have our Forward Looking Public Roadmap, which we monitor and update with what we’re actively working on.

Could you please provide a brief overview of animation tools that were changed and added in Unreal Engine 5.5?

In the past few releases, we’ve been focused on improving all sorts of rigging and animation-related workflows in Unreal. For UE5.5 we worked on improving performance, many Sequencer workflows, proper animation layers, and giving animators access to some pretty cool deformers.

Our tools are rapidly evolving and enabling Unreal Engine to be a toolset where animators can address all of their keyframe animation needs. You can pose in intuitive ways, easily space switch and constrain objects, use various tween tools, temporary pivots, motion trails, pose libraries, and now animation layers to help you animate. You can even add a variety of deformers on demand, whenever you need to push some shapes and extremes.

Can you tell us more about Skeletal Editor in 5.5? What was added to the tool to make it production-ready?

We focused heavily on real world production workflows for the Skeletal Editor in the 5.5 release. Since artists have been comfortable using rigging tools in other software such as Maya for decades now, we knew we had to spend a lot of time making the Skeletal Editor as familiar and functional as possible for artists. We developed a key feature that gives artists the ability to paint skin weights during runtime. This means you can run and play a game or shot in PIE (Play-in-Editor) mode and adjust how your character deforms in real-time. Allowing for direct feedback like this on a rig you are working on is incredibly powerful for riggers and artists alike.

Another feature we added is the ability to edit mesh LOD (level of detail) weights, previously a difficult process that required a lot of back and forth between other software tools. These functional updates for the Skeletal Editor enabled our Fortnite Technical Animation teams to use Unreal Engine as a one-stop-shop for developing game characters without having to migrate between other DCCs like Maya or Blender.

What about 5.5's Sequencer, how was it improved? Could you please tell us more about the novel Timewarp Curves feature?

A big focus for us in 5.5 was to improve Sequencer usability. The team spent a lot of time reviewing areas that could be improved, for example:

Sequencer Details now makes it easier for you to access items that were previously buried deep in right-click menus like HBias.

Our filter system was rewritten making them more accessible and powerful, and we also added a new visibility system where users can isolate or hide items at will. Sequencer can at times be very dense with data but you can now very easily control what data you are looking at while you’re working in it, for example isolating just one character, just a Transform Track, or just a few tracks from a control.

Conditionals – For gameplay cinematics, users can tune parts of their sequence to be active/non-active based on player choice or memory performance. Some examples are playing different subsequences based on player choice, or playing a more performant subsequence on mobile vs. higher-end platforms.
Custom Bindings – For gameplay cinematics, users can author how they want sequences to bind to dynamically created objects at runtime. This can be useful for dynamic objects such as NPCs, where the sequence can choose to animate the nearest NPC to the player.
A new transform origin track was added to our sub-sequences letting you adjust their location and/or orientation in a much simpler way. This is useful for offsetting only parts of a sequence rather than the whole and having to reanimate it.
Our new Timewarp system, developed by Andy Rodham, gives artists all sorts of new abilities like controlling the speed and timing, playing things in reverse, or even playing things in step mode. These can be added globally, on individual animation sequences, or even on an entire subsequence. You can use either a playrate curve or a timewarp curve to adjust the playback. When you mix our timewarp system with our layered control rigs, you can edit motion in ways you can’t do as easily in other systems.

And what about the new Animation Layers, what new workflows do they introduce to make the lives of animators easier?

Animation Layers were a highly requested feature by many animators coming to animate in the engine. They are a non-destructive workflow, letting you more easily control where your keyframes are going and how they influence what you are working on. While we have always had sections in the Sequencer that are very similar, this puts a much friendlier interface on top of them with added functionality like:

Multi-object layers
Ability to add/remove items at will
Additive and/or Override.Merging just selected layers
Muting/Locking
Ability to animate the weights of these layers

Can you tell us more about the other significant animation upgrades in 5.5, like the ability to author animatable animation deformers in Control Rig, the AnimatorKit plugin, and others? Which of the upgrades would you call the highlight of the release?

There were so many amazing teams that contributed to 5.5 and our goal has really been to make each release better than the last.

Deformers have long been an area users have wanted more of in Unreal Engine. I am very excited with 5.5 because we have taken a giant leap forward in how Deformers are authored and also how they’re accessed and used, even on a per-shot basis. You can now easily embed Deformers within the Control Rig itself and/or even add Deformers on the fly in the Sequencer as needed.

There is also a new AnimatorKit plugin, that when enabled gives you access to a few new Deformers and utility rigs that you can use on a shot-by-shot basis to adjust shapes, push and exaggerate motion, amplify collision, or even add things like smear frames.