Unreal Engine 5 (draft)

Draft. Not yet verified in Unreal. Unreal 5 is spike 1's secondary target; this page is the procedure to run and record, written before anyone has run it (reports/spike-1.md).

Why it should be easy

The skeleton uses UE mannequin names as Quaternius' Universal Animation Library spells them (root, pelvis, spine_01..03, neck_01, Head, clavicle_l, upperarm_l, ...). That is the UE4 mannequin's layout. UE5's Manny has two more spine joints (spine_04, spine_05) and different proportions, so UE5 animations still go through the IK Retargeter, but its auto-mapping recognises the names.

Import (UE 5.3 or later, Interchange)

  1. Drag the .glb into the Content Browser. Unreal's Interchange glTF importer opens.
  2. Mesh: Skeletal Mesh on; Import Morph Targets on; Create new skeleton (the first time; later Dramatis characters can share it, since every export has the same 65 joints).
  3. Leave scale at 1: glTF is in metres and Interchange converts to centimetres and to Z-up.
  4. Import. Check:
    • the Skeleton has 65 bones, root at the top, with the names above;
    • the Skeletal Mesh has all the parts as sections or as separate skeletal meshes, depending on the import's Combine setting;
    • Morph Targets lists the 59 face units (JawDrop, ...);
    • the character stands on the floor, facing +X (Unreal's forward) or +Y; record which.

A third-party animation

UAL directly. Import UAL1.glb (Quaternius, CC0) the same way, choosing the Dramatis skeleton as its skeleton (or importing its own and marking the two Compatible Skeletons in the Skeleton editor). The joints and their rest frames are the same, so its clips should play on the character with no retargeting. Record whether the root's -90° X rotation (UAL's, which the export copies) comes through without a turn.

UE5 Manny clips. Make an IK Rig for the Dramatis skeleton (Auto Create Retarget Chains, then Auto Create IK, in 5.4+), and an IK Retargeter from IK_Mannequin to it. Export a few Manny animations (walk, idle) and check the feet stay on the floor.

What to record

For the report, per step: what ran, what had to be changed by hand (that is a failure of "no manual fixes"), and a screenshot of the walk at mid stride with clothing.