Inside Unreal: Animating with the Control Rig Sample Project

The A-Pose is much closer to a natural state that the arms will animate around, being more central to the shoulder’s most commonly used range of motion. It’s not that often to have animations where the arms go straight out like a T-Pose gives you, or even reaching upwards. The benefit is that when skin weighting a character, you get much less deformation on top of the shoulders and less crunch in the armpits to deal with, and it’s easier to skin the upper arm twist influence in there too. Also, you could argue that setting up the elbow targets in an arm IK solution (or a pole vector in the control rig lingo), is much more straight forward from an A-Pose than a T-Pose. (These are two benefits in my opinion). You can still use T-Pose models without problems … just be sure to get them into an A position before attempting to retarget animations from the default UE4 mannequin.