How to use a single bone control chain to correct an offset crouch animation

In a crouch, the b_Root bone has to move down towards the ground. In UDK all the character animations are stored in the AnimSet and in this is a property called AnimSet | Anim Rotation Only that forces UDK to read off only rotations from the b_Root bone; this is helpful where you will create cyclic character moves but not so good if you want to create a crouch, where the feet are local to the ground, and the b_Root drops down in the Z axis.

In the AnimTree we can fix this by adding a single bone controller to b_Root called from the character rig. The controller also has a Node Name so we can access it in code.

Getting ready

In this example we'll create an empty AnimTree asset, and start from there. For ease of use later, in the Content Browser filters click All Types and right-click on the Animation Trees filter and choose Add to Favorites. This will allow you to easily locate your AnimTree asset as we go. Remember...