Bug with Layered Blend Per Bone nodes not working until reconnected

Development Character & Animation
, ,
1

Since the launch of UE 5.7.4 i have been having a issue with the “Layered Blend Per Bone” nodes, they stop working without any reason and only works when i reconnect something and recompile the asset. Im using them for my characters with Blend Mask option, and it seems they become disabled with this bug. Since the beginning of the development of the project i have the issue that, if i needed to change any bone influence of the masks in my Skeleton asset, to see the changes i needed to do this reconnect and compile thing, even if the changes where in a different assets, the mask changes didnt apply until then.

But right now with the recent update they just stop working without any reason. If i reconnect and compile eveything works fine until it breaks again.

The workflow:

  • Masks stops working
  • Reconnect anything

WJ0M8YH
WJ0M8YH761×361 48.8 KB

  • Compile

j0FuzfF
j0FuzfF339×101 6.71 KB

  • Everything works properly

[Attachment Removed]

2

Hi, we haven’t had any other reports like this related to the layered blend per bone node as far as I’m aware so this is going to take a bit of work to track down the problem. But the behaviour that you describe - even just the original issue you were running into - shouldn’t happen, so something is going wrong.

Do you have any steps that can reproduce this issue in a vanilla version of the engine? And related to that, do you have any engine code changes in your project?

Also, when you say that the node stops working, can you give me more information on that - does this affect the anim bp editor viewport, or meshes in PIE (or both)? And do you end up with the mesh just not animating, or is it that the transforms from the Base Pose pin are being passed through the node without the transforms from the Blend Poses 0 pin not being blended on top?

[Attachment Removed]