Two Bone IK updating a frame later?

Development Character & Animation
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1

I’m setting a system when the position of the tool the character is holding depends of the camera (is a first person game), so I configured an interface that ask to the character for the transform of the point (or points if is a two handed tool) and then apply a Two Bone IK and a Transform Bone. I blend the poses from the shoulder or spine (depending if is a one hand or two hand tool) and so far is working, BUT I think is doing it a frame later. In an idle position you can barely see it, but the faster the movement, the large the difference.

This is how is configured in the anim blueprint:

And this is when the anim blueprint call to the interface:

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I tried changing the Tick Group of both the Skeletal Mesh and the child actor form where the IK info is got, but after tried all the combinations I can think of, the issue persist.

Any ideas?

Thank you all.

2

Well… I kinda answer this question to myself… hahahah

The issue was that the Camera and the Tool are childs of the Skeletal Mesh I can not change their tick since they inherit it from the parent.

The solution was to manually set the camera position relative to the skeletal bone every frame. The Skeletal Mesh has Post-Work Tick update and the Camera and their children have During Physics Tick update and now everything looks like is updating at the same frame which is great.

I don’t like having another tick function, but so far doesn’t seem taking any frame from the performance, so I guess is good.

3

The issue is what you calculate and when - not the tick group.

You want the approximate result of the next frame, not the current one.
For any IK system.