The glTF importer cannot currently bring in collision geometry or sockets like the FBX importer. This is a feature request to add that support.
I think there are two approaches that could work: [TABLE=“align: center, border: 1, cellpadding: 2, width: 95%”]
#1 Mimic the FBX importer.
Treats nodes named SOCKET_[RenderMeshName]_## as static mesh sockets and meshes named [UBX | UCP | USP, UCX]_[RenderMeshName]_## as collision geometry. Familiar to content authors who already use the UE4 FBX static mesh importer. Requires no new glTF extensions/specifications. UE4 specific content authoring.
#2 Collaborate on industry standard collision and socket extensions for glTF.
I have [logged a request for a collision specification on the glTF roadmap issue](https://github.com/KhronosGroup/glTF/issues/1051#issuecomment-554547310). UE4 benefits as DCC authoring tools adopt the collision/socket extension specifications. Since authoring tools know what they are generating, they could warn about problems (like convex hulls that are not actually convex). Might be a candidate for inclusion in the [glTF-Blender-IO](https://github.com/KhronosGroup/glTF-Blender-IO) (the glTF importer/exporter add-on that ships with Blender). DCC tools needs to enhance glTF exporters to provide industry standard collision and socket data. More work to coordinate with the glTF community. At the moment, there is no clear direction for defining collision geometry and nothing regarding functionality like mesh sockets.
I think the best solution is to start with #1, since it can actually get done in a reasonable amount of time with few external dependencies and some of the code can be lifted from the FBX importer. At the same time, pursue #2 and adopt it if it looks like it’s going to pan out.