I know that left-hand IK is for keeping the left hand griping the weapon, because some additive animations, such as aim offset, may make the left hand drift away from where it should grip the weapon.
But what about right-hand IK? What’s the purpose of it?
Hey there,
Apologies for the delay; Epic has been on summer break. The right-hand IK setup is the standard for our skeletons in Unreal and is used for a variety of adjustments. In Lyra, it’s not used directly, but we do have it set up there for retargeting. If you were to apply animations from Lyra to a mesh that doesn’t match, you would want to use that mesh as the visual mesh and then use the ABP_Mannequin_Retarget to ensure the animation transfers appropriately, putting the hands where they need to be.
We talk a bit about it in this live stream. https://www.youtube.com/live/5O-nTNMB19Y?si=m8JKZHkwEUeSWArc
That said, the standard offers many other uses as well outside of this context and Lyra. Having a bone higher in the hierarchy that is animation-driven or procedurally positionally driven, and then having IK reach towards it, can be very powerful for adjusting the hand’s position to anything in the world.
Dustin