MetaHuman Facial Mesh Topology & Vertex Index Consistency Issue

[winter_NaN]

I’ve noticed a discrepancy in the vertex count and topology across different MetaHumans, which is causing problems with vertex index mapping for facial landmark applications.

Specifically, the MetaHuman Keiji (shown in Fig. 1) has a total of 34,617 vertices, while other characters like Cooper (Fig. 2) and Bernice (Fig. 3) both have 34,615 vertices—a vertex count that matches most other MetaHumans I’ve tested.

This difference has led to a critical issue: the vertex indices that correspond to the corner of the mouth for Cooper and other standard-count MetaHumans do not map to the same facial landmark on Keiji. From this, I infer that different MetaHuman characters have distinct mesh topology and vertex semantics.

However, I assumed that all MetaHumans would adhere to a unified template standard for facial mesh structure. This leads me to my questions:

1. Does Epic Games provide official standardized specifications for MetaHuman facial mesh topology? Are there any official documentation or resources detailing these standards?

2. What methods can I use to inspect and verify the spatial location of each vertex index across different MetaHuman facial meshes?（I hope can visualize all vertex index labels on the mesh.）

Any insights, solutions, or links to relevant resources would be greatly appreciated. Thanks in advance!

[amir_hm]

I got exact same problem. And likely it’s bug on the Metahuman generator itself. And it’s always plus two verts. The problem is here inside right lips 3 loops from the inner mouth mesh edge. The vertices are duplicated twice. Combining these will offset many other vertices on the face mesh. So need to remap vertex id after combined outside UE, but then bring it back to UE as Metahuman mesh are another problem.

Edit: I remove the rig > create joint only rig > assembly fix the problem using same Metahuman Character