Rewrite _traverse_xcaf → _author_xcaf_to_usd that recursively authors
USD prims mirroring the XCAF assembly tree:
- Assembly nodes become UsdGeom.Xform prims with local transforms from
each component label's Location (not composed with parents)
- Leaf shapes get definition-space vertices (face_loc only, no instance
placement) — the USD scene graph composes transforms hierarchically
- Coordinate swap (X,-Z,Y) now authored once as a root Xform on
/Root/Assembly instead of per-vertex transformation
- Sharp/seam edges extracted per-part from definition shape (not global)
This fixes misplaced geometry for sub-assembly parts (e.g. KOMP-EIN
roller cages with -45° Z rotation) that were previously lost by the
flat traversal.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Hartmut
3dcfa7c0bd