[5.7.1] Intermittent T-Pose on Modular Character during Sequencer Shot Transitions

Development Cinematics & Media
, ,
1

Hello, I am currently developing with Unreal Engine 5.7.1. I am encountering an issue where a modular character intermittently flickers into a T-Pose during shot transitions (scene cuts) in the Sequencer, instead of playing the assigned animation sequence.

To be precise, when I describe it as a “T-Pose,” I mean that the character defaults to the base sequence defined in the Animation Blueprint (which happens to be a T-Pose), completely ignoring the AnimMontage data that should be playing. This happens intermittently during cutscene transitions.

I would appreciate any advice or insights into why this might be happening.

1. Issue Description

  • During Sequencer shot transitions, the character occasionally renders in a T-Pose.
  • The Animation Tracks in the Sequencer are set to “Restore State”.
  • Crucial Observation: When the character renders in T-Pose, debugging confirms that both MontageInstances and ActiveMontagesMap in the character’s AnimInstance contain valid values. The data is there, but it is not being reflected in the final pose.

2. Character Setup

  • Class: Inherits from ACharacter.
  • Structure: Base Mesh (Body) + Attached Skeletal Meshes (Face, Arms, Feet, etc.).
  • Tick Settings (Base Mesh):
    • VisibilityBasedAnimTickOption: AlwaysTickPoseAndRefreshBones
    • TickGroup: PrePhysics
    • TickInterval: Forced to 0.0 when entering the cutscene (may vary outside cutscenes).
  • Character Settings:
    • CharacterEndPhysicsTickFunction.TickGroup = TG_EndPhysics

3. Bounds & Attachment Configuration

  • Base Mesh (Body):
    • bUseAttachParentBound: false
    • bComponentUseFixedSkelBounds: false
    • bSkipBoundsUpdateWhenInterpolating: true
    • bUseBoundsFromLeaderPoseComponent: false
  • Attached Meshes (Arms, Feet, etc. - except Face):
    • bUseBoundsFromLeaderPoseComponent: true
    • bUseAttachParentBound: true
    • bComponentUseFixedSkelBounds: false
    • bSkipBoundsUpdateWhenInterpolating: true
  • Face Mesh (Specific Setup):
    • Uses AnimBP with Copy Pose From Mesh node (copying from Base Mesh).
    • bUseBoundsFromLeaderPoseComponent: false
    • bUseAttachParentBound: false
    • bComponentUseFixedSkelBounds: false
    • bSkipBoundsUpdateWhenInterpolating: true

4. Attempted Solutions

  • I tried changing the TickGroup of the configured meshes to TG_PostUpdateWork before entering the cutscene, but the issue persists.

Could this be related to the evaluation order between “Restore State” and the next shot, or perhaps a Tick dependency issue where the Montage data is valid but the pose evaluation skips the Montage slot for a frame?

Thanks.

[Attachment Removed]

2

[Image Removed]Additional Information

Our AnimBlueprint is currently utilizing multi-threaded animation updates.

[Attachment Removed]

3

Additionally, the test sequence is configured as follows [Image Removed]

[Attachment Removed]

4

[Image Removed]our project, we set up the appearance after BeginPlay. However, for characters used in cutscenes, we bind to actors that are already spawned in the world.

[Attachment Removed]

5

Hey there,

Thanks for the excellent information on this. I’m currently not convinced this is related to the characters themselves, could you share an example of your shot structure within one of those subsequences and the details of the character track? I’m looking to see how the character is bound and how the sequencer animation plays on that character (is it a custom mode)? I’d like to reproduce the setup locally. (If you can share an example repro with content you have, that would be the most helpful)

T-Posing on characters during cuts like this was a bug, but we’ve addressed it. Because you are binding the animation to prespawned characters, I don’t think your modular setup, or any of the properties set, should cause an issue.

Dustin

[Attachment Removed]

6

We actually recently resolved this issue. The problem was occurring while URO (Update Rate Optimization) was enabled, and it disappeared after we disabled it.

My question is:

Since URO adjusts the animation tick interval based on Screen Size, is it expected behavior for this optimization to remain active and apply to characters even during cutscenes (Sequencer)?

[Attachment Removed]

7

Hey there,

That makes sense. Yes, it is expected that URO will continue to run during sequencer. It will run any time a pose is ticked, and you will need to manage when you don’t want it to run. There might be cases where a pose is force-ticked in sequencer, specifically during initialization of a spawnable, but that is it.

Dustin

[Attachment Removed]