In the Unreal docs it is noted that both IK Rig and Control Rig can be procedurally affected in animation blueprints. What are the ideal use cases for using one over the other to achieve Full Body IK adjustments to animations at runtime, if I am not intending to ever manually animate on the Control Rig? Can IK Rig be used for things like the Valley of the Ancients slope warping just as well as Control Rig was?
Thanks!
IK Rig is a simplified “rig” that specializes in IK. It uses a stack of solvers and an array of input goal transforms to generates a pose. The IK Rig also acts as a home for retargeting characterization data.
Control Rig is a much broader rigging system that can do procedural modifications at runtime, or be used for keyframe animation in Sequencer.
In the future, IK Rigs will be able to be embedded in Control Rigs providing a convenient way to create and tune IK setups for use in larger, more sophisticated runtime or keyframe rigs.
For now, IK Rigs are primarily useful as a way to interactively create and tune IK setups for use in an animation blueprint, or to transfer animation between different skeletal meshes using the IK Retargeter asset.
IK Rigs can be used anywhere you would otherwise use one of the many different IK nodes in the anim graph. Regarding Full Body IK, the solver is identical between IK Rig and Control Rig, so it’s really a matter of which suites your particular use case better when deciding which to use. For retargeting, you will need an IK Rig. For simple IK tasks at runtime, I would probably opt for an IK Rig anim node. For sophisticated procedural modifications or keyframe animation, go with Control Rig!