Root Motion in Unreal

Author: Landon Henry

In the recent iterations of Luddite, we have been using Mixamo models and animations for the game. This is convenient but it does come with its own set of challenges. Our combat animations will be using root motion, but here's the issue. The animations we have don't have a designated root bone. Instead, they use the hip bone as the root, which seems to be causing problems with the root motion. After the root motion animations end, the player will be facing the wrong direction and will be slightly tilted to the side. This obviously is a big problem because it interrupts the flow of the game, and as you fight, the character will eventually be parallel to the ground and there is a bunch of glitchy nonsense. 

After messing around with the animations for a while, Adam told me that it looked like it was the capsule collider that was moving incorrectly after the animation played. Sure enough, after turning "show collision" on, you could clearly see the player's capsule component wobbling like crazy throughout the animation. When the animation finished playing you could see the capsule ended tilted to the side and facing the wrong direction. My temporary fix for this was to set the player's rotation after the animation finishes, but this has a big pitfall as if the player keeps attacking the animation will never "finish" and the character will tilt more and more and more. This is still an issue and will need to be fixed as soon as possible. I've been doing some research and as far as I can tell, the only way to fix it will be to edit the rig itself. Not looking forward to that...