AI-driven head rework: judge picks the decimated MakeHuman head over the displacement shell

docs/3d-model-review.md

@@ -232,6 +232,24 @@ brow −0.150, chin −0.149, jaw step −0.11, forehead −0.126→−0.078. Th
 forehead, a defined ear helix/lobe, a jawline that steps to the neck) is folded into the §3.2
 variant comparison; the neck is part of `_skin_body`, so the standalone head always lacks it.
 
+### AI-driven head rework (2026-11-04)
+
+The head was reworked against an AI-generated target concept (front + profile, saved under
+`tmp/npc-parts/head_concept_*.png`) and judged with `describe_image.py` across several iterations.
+The displacement-on-sphere approach oscillates between "decorated egg" (too subtle) and
+"spiky wedges" (too aggressive) and settles at ~3/5 — the coarse s48 sphere cannot resolve the
+nose/lip/chin relief cleanly.
+
+The judge then compared the displacement head against the **decimated MakeHuman head**
+(extracted from `makehuman_retargeted.glb`, 2,009 verts / 1,573 tris, saved as
+`tmp/npc-parts/makehuman_head.glb`) and returned a decisive result: **ship the MakeHuman head** —
+it keeps the nose/chin/jaw landmarks at a fraction of the cost, while the procedural head's
+"clean ellipse outline instantly screams procedural sphere".
+
+**Conclusion:** the next head asset is the MakeHuman head shape (1,573 tris) plus the project's
+separate eye/mouth/brow pieces for readability, not the displacement shell. The displacement
+`_head_proto` stays local as a rejected variant.
+
 ### Head subdivision comparison (2026-11-04)
 
 Three `head_proto` variants at UV-sphere segments 24/48/64 were rendered at 1.85 m and 1.5 m in