forked from 1b-agent/fieldcraft-upstream
`fieldcraft_mesh::octree::octree_hex_mesh` meshes any closed part with hex8 only: - an adaptive 3-refinement grid (27-tree) with strong balance and closure, filled with conforming node-marking transition templates (Schneiders; checked over all 48 symmetries); - a core of grid cells kept clear of the boundary (the HybridOctree buffer rule), with non-manifold cleanup and a genus check against the part; - a feature graph from the B-rep (corners, curves, patches) and a partition-first map of the core's boundary onto it, then two boundary layers: a padding layer and a pillow per patch, so every face boundary and sharp edge is captured by element edges; - a Garanzha-type untangling and fitting energy (shape term |J|^3/chi, a volume term and a soft fitting term, deterministic across platforms), a compass search on the worst elements and a certified repair; failures refine the grid near them and rebuild, within bounded attempts and growth. The output passes the certified Jacobian check of every element and a gate that the boundary encloses the elements' volume; boundary quads carry their B-rep faces. Quality is reported with the same scaled Jacobian as mesh.quality. Literature notes for each step are in docs/meshing/literature.md (B1.6-B1.10). Co-Authored-By: Claude Opus 5.5 <[email protected]> Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm