Look At

The Look At Skeletal Control Node can be used to specify a Bone to trace or follow another Bone in the Skeleton.

LookAtnode.png

Below, our character has two packs on their left side which use the Look At control node and are set to follow a foot bone.

Inside the viewport, a yellow debug line is a visulalization tool to help see which Look at Bone the Bone to Modify is following.

You may need to enlarge the video to see the debug line or try it out in the editor.

Property Description

Skeletal Control

Bone to Modify Name of the Bone to control. This is the main Bone chain to modify from.
Look at Axis Which axis to align to look at point.
Use Look Up Axis Whether or not to use look up axis.
Look Up Axis Look up axis in local space.
Look at Clamp Look at Clamp value in degrees. If your Look at axis is Z, only X, Y degree of clamp will be used.
Interpolation Type The interpolation method to use.
Interpolation Time The time used during interpolation.
Interpolation Trigger Threshold The threshold in which to trigger interpolation.
Enable Debug Whether or not to enable debug display.

Target

Look at Bone Target Bone to look at. You can't use Look At Location as an alternative as you'll get a delay on Bone location if you query directly.
Look at Socket Target Socket to look at.
Look at Location Target location in world space if Look At Bone is empty.
Pin Description

Input Pins

Component Pose The incoming pose.
Alpha The current strength of the control.

Look At nodes are also affected by the LOD Threshold system introduced in 4.11. You can find the setting for this in the Details Panel for the Look At node.

perf.png

Property Description
LOD Threshold This is the max Level of Detail (LOD) that this node is permitted to run on. For example: if you have LOD Threshold set to 2, it will run until LOD 2, but disable itself once the component's LOD becomes 3.