# Anatomy model attribution & licences

The 3D assets in `public/models/anatomy/` are derivative works built for this
website. Each source has its own licence — they are **not** all the same.

| Asset | Source(s) | Licence |
| --- | --- | --- |
| `body-shell.glb` | Blender Studio — Human Base Meshes | CC0 1.0 (public domain) |
| `muscular-system.glb` | Z-Anatomy (← BodyParts3D) | CC BY-SA 4.0 |
| `skeletal-reference.glb` | Z-Anatomy (← BodyParts3D) | CC BY-SA 4.0 |

Because `muscular-system.glb` and `skeletal-reference.glb` derive from
Z-Anatomy, **they inherit CC BY-SA 4.0**: they may be reused and modified, but
must keep attribution and be shared under the same licence (ShareAlike).
`body-shell.glb` derives from a CC0 source and carries no such obligation.

See the per-source files in this folder for the full text and required
acknowledgements:

- `z-anatomy.txt` — Z-Anatomy + BodyParts3D (muscles, bones)
- `human-base-meshes.txt` — Blender Studio Human Base Meshes (body shell)
- `open3dmodel.txt` — note on the Open3DModel upper/lower-limb archives

## What was retained vs removed

**Retained** from Z-Anatomy (musculoskeletal only): selected superficial and
key clinical muscles of the neck, shoulder/rotator cuff, arm/forearm, trunk,
hip, thigh and leg; and whole bones of the spine, thorax, pelvis, shoulder
girdle, arm, hand, femur/patella/tibia/fibula, foot, and a minimal cranium.

**Removed** (not present in the published assets): all viscera, blood vessels,
nerves, lymphatic and glandular structures, brain and sense organs, facial
mimetic muscles, fascia/aponeuroses/bursae/tendon-sheaths, cartilage, discs,
Z-Anatomy label/annotation meshes (`.i`/`.j`/`.g`), cameras, lights and helpers.

## Modifications made

- Extracted a musculoskeletal subset from `Startup.blend`; removed all
  non-musculoskeletal systems and annotation meshes.
- Rebuilt the left side of the skeleton by mirroring the right across the
  midline (the source left bones are a collapsed mirror).
- Merged the kept meshes into one object per clinical region per layer.
- Decimated geometry (silhouette-preserving) and applied Draco compression.
- Normalised all three layers to a shared frame (1.70 m, feet at origin, Y-up).
- The body shell is the CC0 "female realistic" base mesh with the facial
  features smoothed to remove identity and the eyeballs removed.

Runtime materials, colours and opacity are applied in the website code and are
not baked into the GLB files.