There is bunch of great assets on the Unreal Marketplace from the Synty Studios called POLYGON. They include plenty of stuff, they are neat, but they all lack animations. If you’re reading this, then you have probably tried to retarget Polygon characters to use Unreal mannequin-based animations (from packs like MCO Mocap Basics or the default ones) and ended up with something like this:
The issue here is that the Polygon skeleton uses a T‑pose, while the Unreal skeleton uses the A‑pose:
Let’s fix this real quick.
1. Open the Unreal Skeleton
It’s called UE4_Mannequin_Skeleton in most cases.
2. Open the Retarget Manager
If you don’t have that tab opened, click the Retarget Manager button on the top toolbar
3. Make sure to select the Humanoid rig
It’s the dropdown option in the Set up Rig section:
4. Modify mannequin pose
Rotate the upperarm_l and upperarm_r up using the green axis, 50 degrees both.
Then the lowerarm_l and lowerarm_r slightly back using the blue axis, -20 degrees both.
Finally, rotate the lowerarm_l and lowerarm_r slightly down using the green axis, -10 degrees both.
You could also rotate the hand_l and hand_r slightly up, 10 degrees both.
Then click Modify Pose and then Use Current Pose:
Save the file. Now the mannequin is ready to be used to retarget Polygon characters animations.
5. Retarget the animation
In the content browser, find the animation you want to retarget, right-click it, hover the Retarget Anim Assets and click Duplicate Anim Assets and Retarget.
In the left side of window that opens select the Polygon skeleton (the name differs from pack to pack, but in the City pack it’s called SK_Character_City_Rig), the preview of the skeleton should appear in the right preview box. You can specify the prefix, the suffix and choose to replace the part of the name of the animation you’re retargeting. You can also specify where the duplicated animation will be stored:
If you prefer the video version on how to retarget Polygon characters, you can always watch the full video this tutorial is based on. There’s also a chance you may want to read on various post-processing settings in Unreal Engine: How to Achieve Cinematic Quality With Post-Process Effects in Unreal Engine 4.