Add MakeHuman head hair/body prototype and 12-variant rollout plan

MEMORY.md

@@ -10,15 +10,23 @@ canonical implemented-features list in `docs/development-status.md`.
   the licence gate. Downloads live in `tmp/research/` (gitignored): DDG image search, street-view
   frames, neighbouring buildings — never committed, never shipped. Promotion into
   `docs/screens/refs/` always passes the sidecar licence + privacy gate and `CREDITS.md`.
-- **MakeHuman head prototype (2026-11-04):** `assets/models/blender_src/makehuman_head.glb`
-  is a local 12,641-tri/7,690-split-vert head derived from the CC0 MakeHuman base,
-  with a review sheet and `docs/makehuman-head-review.md`. The latest build uses a
-  skin eyelid mask (almond aperture cut from a sphere), recessed globes, flat iris/pupil
-  discs and surface-anchored brows. The automated vision gate still rejected it:
-  the eye depth reads inconsistently across front/three-quarter/profile and the lid
-  does not visibly overlap the globe. It is not rigged, textured, integrated or
-  shipped; keep the source/rejected parts in `tmp/` until real eyelid masses pass
-  the gate.
+- **MakeHuman head accepted (2026-11-04, owner):** the basic human head is a pass.
+  `assets/models/blender_src/makehuman_head.glb` is the CC0 MakeHuman-derived head
+  (12,642 tris / 7,690 split verts). The automated vision gate still records REJECT on
+  the eye/lid region (globe depth, lid overlap, iris at three-quarter) as deferred
+  polish, not a blocker. The assembled path (`build_character(head="mh")`) adds a
+  skull-conforming hair cap derived from the closed head shell, hides the scalp under
+  that cap, and narrows the neck/shoulder body. Default head source stays `face` until
+  the owner reviews the hair/body and the 12-variant rollout starts.
+- **MakeHuman hair/body prototype (2026-11-04):** `npc_casual --head mh` is
+  14,753 tris / 12,822 raw / 12,823 seam-split verts / 14 bones / 9 materials,
+  `inspect` clean. All 12 variants were counted at 14,693–15,987 tris. Hair uses flat
+  shading normals because the old hair normal map caused dark tangent patches on the
+  new cap. Scalp faces fully covered by the hair cap are deleted (saves ~950 tris);
+  the accepted face geometry is untouched. The procedural body was narrowed at the
+  neck/shoulders (shoulder root z 1.345, chest 0.158, neck 0.060/0.054) and its skin
+  decimate dropped to 0.21. The local renders are in
+  `tmp/npc-parts/prototype_mh/renders/`.
 - **Project agent skills (2026-11-03):** two tracked skills live in `.agents/skills/`:
   `gig-line-blender-asset-contract` and `gig-line-release-qa`. They are guidance only,
   add no runtime dependency and are referenced from `tools/README.md`. The third-party
@@ -114,6 +122,12 @@ canonical implemented-features list in `docs/development-status.md`.
   out of a portrait frame (park the rest of the crowd away instead).
 - Blender: `bisect_plane` and thin bevels leave zero-area triangles (Godot "non-finite normal in
   LOD generation"); `_clean()` + a weld after bisect fixes them and the audit rejects them.
+- MakeHuman head/hair gotchas: the imported head is broad and flat, so a separate hair
+  ellipsoid floats or leaves a bald patch; derive the cap from the closed head shell and
+  boolean-cut the hairline. Do not reuse the skull's UVs with the old `hair_normal.png`
+  (dark tangent patches) — hair skips the normal map. Generate the cap before deleting
+  the hidden scalp, or the cap inherits the hole. The flatpak sandbox cannot read `/tmp`;
+  helper scripts must live under `$PWD`.
 - Image models have per-model size floors/caps (Seedream needs 1920+; `GEN_SIZE=2048`, do not
   lower; gpt-5-image-mini caps lower). `generate_image` applies model-specific sizing; concept
   generation defaults to `--request-size 1536`.

TODO.md

@@ -26,10 +26,12 @@ five tint slots, 16,000/16,000 character cap, optional extra bones beyond the re
 **Current state:** `assets/models/npc/` contains the tracked frozen `npc_base.blend` and its
 gitignored `.blend1`; the 12 production characters are assembled procedurally by
 `tools/blender_assets.py` from `_shape_head_mesh`, `_face`, `_hair` and `_hands_and_shoes`.
-There is no per-part source asset library yet. The MakeHuman body prototype and its temporary
-head/hand swap live under `tmp/npc-research/` and are not the shipped path. This overhaul supplies
-the reusable head/face and hand parts that both the procedural characters and the MakeHuman body
-can consume.
+The MakeHuman head is now a second head source (`build_character(head="mh")`,
+`build --head mh`, `npc_parts.py assemble --head mh`) and all 12 variants assemble inside the
+16,000-triangle cap with it. The procedural body, hands and clothing remain unchanged. The
+MakeHuman body prototype and its temporary head/hand swap live under `tmp/npc-research/` and are
+not the shipped path. This overhaul supplies the reusable head/face and hand parts that both the
+procedural characters and the MakeHuman body can consume.
 
 This workstream supersedes the face/head and hands items in §C until the prototypes are approved;
 the rest of §C remains the broad review checklist.
@@ -93,16 +95,18 @@ the rest of §C remains the broad review checklist.
 - [x] Compare two or three subdivision/loop variants at 1.85 m front/three-quarter/profile and a
       1.5 m portrait. Pick the variant that reads best before changing all 12 characters; keep the
       rejected variants local.
-- [-] Rebuild a standalone MakeHuman-derived head from the researched CC0 base and save it to
+- [x] Rebuild a standalone MakeHuman-derived head from the researched CC0 base and save it to
       `assets/models/blender_src/makehuman_head.glb`; record provenance/review in
-      `docs/makehuman-head-review.md` and the preview sheet. (Final build: 12,641 tris / 7,690
-      split verts; assembled `npc_casual` 15,532 tris / 13,310 verts / 14 bones, `inspect` clean.
-      Latest attempt: skin eyelid mask, recessed globes, flat iris/pupil discs, surface-anchored
-      brows. Vision verdict: still **REJECT** — globe depth is inconsistent between front,
-      three-quarter and profile, the lid does not visibly clip the globe, and the iris reads
-      decal-locked at three-quarter; prototype stays local and un-integrated.)
+      `docs/makehuman-head-review.md` and the preview sheet. Final build: 12,642 tris /
+      7,690 split verts, bounds x −0.094..0.094, y −0.180..0.042, z 1.530..1.803. The owner
+      accepted the **basic human head** on 2026-11-04; the automated vision gate still records
+      the eye-region REJECT as deferred polish (globe depth, lid overlap, iris at three-quarter).
+      The assembled path now adds a skull-conforming hair cap, a hidden-scalp trim and a narrowed
+      neck/shoulder body. Assembled `npc_casual --head mh`: 14,753 tris / 12,822 raw / 12,823
+      seam-split verts / 14 bones / 9 materials, `inspect` clean.
 - [ ] Build true upper/lower eyelid masses that overlap the globe in front, three-quarter and
-      profile views (not a socket hole), then re-run the vision gate before integrating the head.
+      profile views (not a socket hole), then re-run the vision gate. Deferred: the owner accepted
+      the basic head, so this is polish, not a rollout blocker.
 
       Compared `head_proto` at seg 24 (670 verts), 48 (1,558 verts) and 64 (2,470 verts) at 1.85 m
       and 1.5 m, front/three-quarter/profile. Vision-judged: **s48 wins** — s24 is too faceted
@@ -117,12 +121,11 @@ the rest of §C remains the broad review checklist.
       imported GLB came out black and is superseded by the proper `.blend`-source bake). Flag: the
       prototype ears reach x ±0.162 vs the 0.1575 head-radius reference, so headgear may clip and
       must be re-measured at rollout.
-- [ ] Get owner sign-off on the one-variant prototype, then roll the approved head/face into the
-      other 11 variants one asset family at a time, with a before/after sheet per batch.
-      **Blocked on owner sign-off.** Sign-off material is ready: the s48 prototype vs the current
-      `_face` at 1.85 m front/three-quarter/profile
-      (`docs/blender_previews/sheet_head_proto_before_after.jpg`); the s24/s48/s64 comparison table
-      is in `docs/3d-model-review.md`. Rollout waits for the owner's go/no-go.
+- [-] Owner review of the assembled one-variant prototype (`npc_casual --head mh`) before the
+      12 shipped GLBs change. The basic human head is accepted (2026-11-04); the review now covers
+      the skull-conforming hair cap and the narrowed neck/shoulder body silhouette. Local renders:
+      `tmp/npc-parts/prototype_mh/renders/` (portrait front/three-quarter/profile + full body).
+      Rollout starts only after this review.
 
 ### 4. Hands and grip prototype
 
@@ -151,6 +154,30 @@ the rest of §C remains the broad review checklist.
 
 ### 5. Assembly and rollout
 
+**MakeHuman 12-variant rollout.** - [x] Make the head source selectable from the main builder:
+      `blender_assets.py build --head mh --only npc_casual,...` and
+      `npc_parts.py assemble --variant <name> --head mh --out <stem>`. The default stays `face`
+      until the hair/body review passes.
+- [x] Verify every variant assembles with the MakeHuman head inside the 16,000/16,000 cap
+      (pre-export triangle counts, `inspect` clean; `npc_casual` seam-split verts 12,823):
+      `npc_casual 14,753`, `npc_jacket 15,153`, `npc_coat 15,817`, `npc_vest 15,579`,
+      `npc_dress 15,215`, `npc_hoodie 15,837`, `npc_firefighter 15,987`, `npc_guard 15,729`,
+      `npc_crowd_a 14,947`, `npc_crowd_b 14,693`, `npc_crowd_c 15,433`, `npc_crowd_d 15,833`.
+- [x] Recover head budget without touching the accepted face: remove head faces fully covered by
+      the hair cap, keep boundary faces as a safety band, and trim the hidden neck plug to 12
+      segments. This saves ~950 tris on every variant.
+- [ ] Owner approves the hair cap and full-body silhouette on the local `npc_casual` prototype.
+- [ ] Rebuild the 12 committed character GLBs with `--head mh`, in asset-family batches, then
+      regenerate their AO maps and manifest entries. Never run a no-op full-library rebuild.
+- [ ] Run `blender_assets.py audit`, `fit`, `inspect` and `texels`, plus
+      `python3 tools/npc_proportions.py report`; record the 12-variant proportion table.
+- [ ] Re-run the Godot NPC tests and capture the 12 × 6 baseline
+      (`src/test/capture_npc_baseline.gd` → `python3 tools/npc_baseline.py sheet`); inspect the
+      sheet for outliers before committing.
+- [ ] Update `docs/makehuman-head-review.md`, `docs/3d-model-review.md`,
+      `docs/blender_previews/README.md`, `docs/npc-model-sourcing.md`, `CREDITS.md` and
+      `docs/development-status.md` with the accepted head/hair/body state and final counts.
+
 - [ ] Integrate the approved parts into `build_character` with deterministic joins, weights, UVs and
       AO. The final output remains one `npc_base` skinned mesh under the existing 13-core armature;
       optional extra bones are allowed but the core rest positions stay fixed;

docs/3d-model-review.md

@@ -260,9 +260,11 @@ welding the added eye/brow pieces into the head shell and a skull-conforming hai
 **Standalone head re-review (2026-11-04):** the separate
 `assets/models/blender_src/makehuman_head.glb` prototype (12,641 tris / 7,690 split verts,
 with a skin eyelid mask, recessed globes, flat iris/pupil discs and surface-anchored brows)
-was **rejected** by the vision gate: the globe depth reads inconsistently between front,
-three-quarter and profile, the iris reads decal-locked at three-quarter, and the lid does
-not visibly clip the globe. It stays local until real eyelid geometry passes; see
+was **accepted by the owner** as a basic human head. The automated vision gate still returns
+REJECT on the eye/lid region (globe depth, lid overlap, iris at three-quarter) as deferred
+polish. The assembled `npc_casual --head mh` now adds a skull-conforming hair cap, a hidden
+scalp trim and a narrowed neck/shoulder body: 14,753 tris / 12,823 seam-split verts /
+14 bones / 9 materials, `inspect` clean. All 12 variants count 14,693–15,987 tris. See
 [`makehuman-head-review.md`](makehuman-head-review.md).
 
 ### Head subdivision comparison (2026-11-04)
@@ -493,7 +495,7 @@ and the full carded-cluster foliage pass is the one remaining owner-gated P1. No
 
 ## Next actions
 
-- Review the standalone [`makehuman-head-review.md`](makehuman-head-review.md) prototype before integrating any head/hand part into the character library.
+- Review the assembled [`makehuman-head-review.md`](makehuman-head-review.md) prototype (hair cap and full-body silhouette) before rebuilding the 12 shipped character GLBs.
 
 
 Tracked in [`TODO.md`](../TODO.md) `3D model re-evaluation`: the remaining `A. Baseline…` item is

docs/asset-tooling.md

@@ -140,11 +140,13 @@ MakeHuman sources against the character contract and records the 2026-11-03 dire
 
 ```bash
 flatpak run org.blender.Blender --background --python "$PWD/tools/blender_assets.py" -- build
+flatpak run org.blender.Blender --background --python "$PWD/tools/blender_assets.py" -- build --head mh
 flatpak run org.blender.Blender --background --python "$PWD/tools/blender_assets.py" -- render
 python3 tools/blender_assets.py sheet   # docs/blender_previews/sheet_*.jpg
 python3 tools/blender_assets.py audit   # no Blender needed
 python3 tools/blender_assets.py fit     # gear-vs-body fit report
 python3 tools/blender_assets.py texels  # per-slot texel density (px/m) of the characters
+# `build --head mh` selects the MakeHuman head; the default stays `face` until rollout.
 godot --headless --path . --import
 ```
 

docs/blender_previews/README.md

@@ -9,7 +9,7 @@ capture harnesses.
 | --- | --- |
 | [![sheet_npc.jpg](sheet_npc.jpg)](sheet_npc.jpg) <br> `sheet_npc.jpg` | Eight skinned character variants (casual, jacket, coat, hi-vis vest, dress, hoodie, firefighter, guard) with their gear attach points. |
 | [![sheet_npc_baseline.jpg](sheet_npc_baseline.jpg)](sheet_npc_baseline.jpg) <br> `sheet_npc_baseline.jpg` | Neutral studio baseline: 8 characters x front, three-quarter, profile, back, full body and crowd views. |
-| [![sheet_makehuman_head.jpg](sheet_makehuman_head.jpg)](sheet_makehuman_head.jpg) <br> `sheet_makehuman_head.jpg` | Local MakeHuman head prototype: front, three-quarter and profile review views. The vision gate rejected this build (inconsistent globe depth and no visible lid overlap); see [`../makehuman-head-review.md`](../makehuman-head-review.md). |
+| [![sheet_makehuman_head.jpg](sheet_makehuman_head.jpg)](sheet_makehuman_head.jpg) <br> `sheet_makehuman_head.jpg` | MakeHuman head: front, three-quarter and profile review views. The owner accepted the basic head; the automated vision gate still rejects the eye/lid region as deferred polish. See [`../makehuman-head-review.md`](../makehuman-head-review.md). |
 | [![sheet_npc_baseline_compare-body.jpg](sheet_npc_baseline_compare-body.jpg)](sheet_npc_baseline_compare-body.jpg) <br> `sheet_npc_baseline_compare-body.jpg` | Neck/shoulder transition: fuller neck base and a lower shoulder root. |
 | [![sheet_npc_baseline_compare-face-detail.jpg](sheet_npc_baseline_compare-face-detail.jpg)](sheet_npc_baseline_compare-face-detail.jpg) <br> `sheet_npc_baseline_compare-face-detail.jpg` | Face detail: nose ala wings, a single rounded mouth and a darker ear concha. |
 | [![sheet_npc_baseline_compare-face.jpg](sheet_npc_baseline_compare-face.jpg)](sheet_npc_baseline_compare-face.jpg) <br> `sheet_npc_baseline_compare-face.jpg` | Face-depth pass: recessed sclera, upper lid and sculpted chin/cheek planes. |

docs/makehuman-head-review.md

@@ -1,9 +1,12 @@
 # MakeHuman head prototype
 
-Status: **local prototype, rejected by the automated visual gate, not integrated.**
-The asset is a standalone head/neck extracted from the CC0 MakeHuman base in
-`tmp/npc-research/makehuman/base.obj`. It is kept as a reviewable experiment and
-is not part of the shipped NPC contract.
+Status: **owner-accepted head, assembled prototype, not yet shipped.**
+The owner accepted the basic human head on 2026-11-04. The automated vision gate
+still records REJECT on the eye/lid region as deferred polish. The asset is a
+standalone head/neck extracted from the CC0 MakeHuman base in
+`tmp/npc-research/makehuman/base.obj`; the assembled path now adds hair, a hidden
+scalp trim and the procedural body. The 12 shipped GLBs have not been rebuilt
+with it yet.
 
 ## Asset
 
@@ -14,10 +17,12 @@ is not part of the shipped NPC contract.
   components, cuts an almond aperture through a skin eyelid mask, adds recessed
   eyeballs with flat iris/pupil discs, anchors brows to the face surface, renders
   front/three-quarter/profile and exports the standalone GLB.
-- Measurements (final build, `inspect`): **12,641 triangles / 7,690 split
-  vertices**; bounds approximately `x ±0.094 m`, `y -0.180…0.042 m`,
-  `z 1.530…1.803 m` in project Z-up space. It is inside the 16,000/16,000
-  character cap.
+- Measurements (final standalone build, `inspect`): **12,641 triangles / 7,690
+  split vertices**; bounds approximately `x ±0.094 m`, `y -0.180…0.042 m`,
+  `z 1.530…1.803 m` in project Z-up space.
+- Assembled `npc_casual --head mh`: **14,753 triangles / 12,823 seam-split
+  vertices / 14 bones / 9 materials**, `inspect` clean. All 12 variants count
+  14,693–15,987 triangles with the same head.
 - Materials used: `skin`, `eye_white`, `iris`, `pupil`, `hair`. No textures are
   baked into this prototype.
 
@@ -69,8 +74,10 @@ Accept only if:
 
 ## Judge result
 
-**VERDICT: REJECT** (vision judge `z-ai/glm-5.3-flash`, final build render set
-above). The gate is blocked; the prototype is not presented as an accepted head.
+**Owner verdict: ACCEPT (basic human head, 2026-11-04).**
+**Automated vision gate: REJECT** (vision judge `z-ai/glm-5.3-flash`, final
+standalone build render set above). The eye/lid findings below remain deferred
+polish; they are no longer a rollout blocker because the owner accepted the head.
 
 Blocking findings:
 
@@ -96,24 +103,37 @@ Should-fix findings:
 - the catchlight is baked geometry and is not consistent between eyes.
 
 What passed: the skin/eye material remap is correct, the eye openings are
-closed, the standalone GLB reports **12,641 triangles / 7,690 split vertices**
-with no issues, and an assembled `npc_casual` with this head passes `inspect` at
-**15,532 / 16,000 triangles, 13,310 split vertices, 14 bones, no issues**.
+closed, the standalone GLB reports **12,641 triangles / 7,690 split vertices**,
+and an assembled `npc_casual` with this head passes `inspect` at **14,753 /
+16,000 triangles, 12,823 seam-split vertices, 14 bones, no issues**.
 
 Known limits: bald mannequin-like presentation, stylized geometry-only
 iris/pupil, no rig, no UV texture pass, and the neck cap is a review cut rather
 than a body-welded seam.
 
-## Next steps after the gate passes
+## Assembled prototype (2026-11-04)
+
+- `_makehuman_head` imports the GLB and adds a **skull-conforming hair cap**
+  derived from the closed head shell (scaled shell + boolean front-sphere
+  cut + decimate). Hair skips the old `hair_normal.png` because the skull UVs
+  produced large dark tangent patches.
+- Head faces fully covered by the cap are deleted to recover ~950 triangles;
+  boundary faces stay as a safety band, so the accepted face geometry is
+  untouched. The hidden neck plug uses 12 segments.
+- The procedural body was narrowed at the neck and shoulders (chest 0.158,
+  neck base 0.060, neck top 0.054, shoulder root z 1.345) and its skin decimate
+  dropped to 0.21 so all 12 variants fit the 16,000 cap.
+- Local review renders: `tmp/npc-parts/prototype_mh/renders/` (portrait
+  front/three-quarter/profile and full-body front/three-quarter).
+
+## Deferred polish
 
 - Replace the radial lid mask with real upper/lower lid masses that fold over
   the globe, with pointed canthi, and pass the profile view.
 - Move the iris onto a curved cornea cap so its orientation follows the globe at
   three-quarter angles, and use a lighting-driven catchlight instead of baked
   white geometry.
-- Compare against the project `_face` baseline and decide whether this head is
-  the base for the local head/face overhaul.
-- Add a clean UV/material pass and a contract armature/weights if it becomes
-  part of a library character.
-- Keep the source script under `tmp/`; promote only the reviewed GLB and durable
-  docs/preview sheet.
+- Refine the hair cap silhouette (current short cap reads as a helmet) and
+  improve the full-body shoulder/arm shape before the 12-variant rollout.
+- Add a clean UV/material pass and a contract armature/weights when the head
+  becomes part of the shipped library characters.

docs/npc-model-sourcing.md

@@ -46,13 +46,13 @@ project head/hands swap reduced this to **6,407 / 16,000 tris and**
 **6,651 / 16,000 verts**, but manual shoulder/neck retopology and part cleanup
 remain before it can be considered shippable.
 
-A standalone MakeHuman head prototype is recorded in
-[`makehuman-head-review.md`](makehuman-head-review.md); it remains local/un-integrated
-until the overhaul accepts it.
-
-The head/face/hand overhaul in [`TODO.md`](../TODO.md) is the prerequisite: the
-MakeHuman body should reuse the approved local head/hand parts rather than
-forking a second face implementation.
+A standalone MakeHuman head is recorded in
+[`makehuman-head-review.md`](makehuman-head-review.md). The owner accepted the basic
+human head on 2026-11-04; the assembled path (`build_character(head="mh")`) adds a
+skull-conforming hair cap and hides the scalp under it. The 12 shipped GLBs still use
+the procedural head until the hair/body review and rollout in [`TODO.md`](../TODO.md).
+The MakeHuman body should reuse the approved local head/hand parts rather than forking
+a second face implementation.
 
 ## Provenance rules
 

docs/screens/head-review/README.md

@@ -3,8 +3,8 @@
 > **Historical page / changed source (2026-11-04).** The numbers below describe the
 > earlier decimated MakeHuman head (1,548-tri skin). The shared source
 > `assets/models/blender_src/makehuman_head.glb` now holds the higher-resolution
-> standalone prototype; its automated vision gate returned **REJECT** (inconsistent
-> globe depth across views and no visible lid overlap). See
+> standalone prototype. The owner accepted the basic head; the automated vision gate
+> still records REJECT on the eye/lid region as deferred polish. See
 > [`../../makehuman-head-review.md`](../../makehuman-head-review.md). Re-run the
 > library head build before relying on the comparison counts below.
 
@@ -60,8 +60,9 @@ Left to right: front, three-quarter, profile.
 4. The head skin is 1.5k tris (smooth but low-poly); a retopology pass could add resolution if a
    portrait shows faceting.
 
-## Decision needed
+## Decision (2026-11-04, owner)
 
-Approve or reject the MakeHuman-head direction. If approved, the next step is rolling it into the
-other 11 variants (one asset family at a time) with a before/after sheet per batch, and re-running
-the 24-NPC budget + AO bake.
+The MakeHuman-head direction is approved for the basic human head. The remaining review is the
+assembled prototype's hair cap and full-body silhouette. After that, roll the head into the other
+11 variants (one asset family at a time) with a before/after sheet per batch, then re-run the
+24-NPC budget + AO bake.

tools/blender_assets.py

@@ -276,13 +276,17 @@ def material(name, textured_solid=False):
                                             check_existing=True)
         albedo.image.colorspace_settings.name = "sRGB"
         links.new(albedo.outputs["Color"], bsdf.inputs["Base Color"])
-        normal_tex = nodes.new("ShaderNodeTexImage")
-        normal_tex.image = bpy.data.images.load(
-            str(NPC_TEX_DIR / f"{name}_normal.png"), check_existing=True)
-        normal_tex.image.colorspace_settings.name = "Non-Color"
-        nmap = nodes.new("ShaderNodeNormalMap")
-        links.new(normal_tex.outputs["Color"], nmap.inputs["Color"])
-        links.new(nmap.outputs["Normal"], bsdf.inputs["Normal"])
+        # The hair normal map was authored against the old cap UVs. Reusing it
+        # on the skull-conforming MakeHuman cap produces large dark tangent
+        # patches, so hair keeps its albedo but takes flat shading normals.
+        if name != "hair":
+            normal_tex = nodes.new("ShaderNodeTexImage")
+            normal_tex.image = bpy.data.images.load(
+                str(NPC_TEX_DIR / f"{name}_normal.png"), check_existing=True)
+            normal_tex.image.colorspace_settings.name = "Non-Color"
+            nmap = nodes.new("ShaderNodeNormalMap")
+            links.new(normal_tex.outputs["Color"], nmap.inputs["Color"])
+            links.new(nmap.outputs["Normal"], bsdf.inputs["Normal"])
         rough = {"skin": 0.6, "cloth": 0.86, "pants": 0.92,
                  "accessory": 0.5, "hair": 0.7}[name]
         bsdf.inputs["Roughness"].default_value = rough
@@ -550,22 +554,21 @@ def _skin_body(spec):
                     "guard": 0.05}.get(layer, 0.0)
     leg = 1.0 + {"responder": 0.1, "dress": -0.1}.get(layer, 0.0)
     nodes = [  # (pos, radius_x, radius_y)
-        ((0, 0, 0.80), 0.168 * w, 0.116 * d),       # 0 pelvis
-        ((0, 0, 0.96), 0.146 * w * bulk, 0.103 * d * bulk),  # 1 waist
-        ((0, 0.0, 1.18), 0.168 * w * bulk, 0.114 * d * bulk),  # 2 chest
-        ((0, 0.0, 1.355), 0.170 * w * bulk, 0.108 * d * bulk),  # 3 upper chest
-        # A slightly fuller neck base and a lower shoulder root give the
-        # head/neck/shoulder line a trapezius slope instead of a thin post on
-        # a hanger. The head and collar still sit above this band.
-        ((0, 0, 1.43), 0.074, 0.072),               # 4 neck base
-        ((0, -0.005, 1.53), 0.060, 0.060),          # 5 neck top
+        ((0, 0, 0.80), 0.158 * w, 0.112 * d),       # 0 pelvis
+        ((0, 0, 0.96), 0.142 * w * bulk, 0.101 * d * bulk),  # 1 waist
+        ((0, 0.0, 1.18), 0.155 * w * bulk, 0.110 * d * bulk),  # 2 chest
+        ((0, 0.0, 1.335), 0.158 * w * bulk, 0.105 * d * bulk),  # 3 upper chest
+        # Narrow neck and a lower, sloped shoulder root. The old wide neck base
+        # and horizontal shoulder shelf made the accepted head read as small.
+        ((0, 0, 1.42), 0.060, 0.060),               # 4 neck base
+        ((0, -0.005, 1.53), 0.054, 0.054),          # 5 neck top
     ]
     edges = [(0, 1), (1, 2), (2, 3), (3, 4), (4, 5)]
     for s in (-1.0, 1.0):
         base = len(nodes)
         nodes += [
-            ((0.20 * s * w, 0, 1.37), 0.080 * t * sleeve, 0.074 * t * sleeve),  # shoulder
-            ((0.27 * s * w, 0, 1.23), 0.058 * t * sleeve, 0.058 * t * sleeve),  # upper arm
+            ((0.19 * s * w, 0, 1.345), 0.070 * t * sleeve, 0.068 * t * sleeve),  # shoulder
+            ((0.27 * s * w, 0, 1.22), 0.054 * t * sleeve, 0.055 * t * sleeve),  # upper arm
             ((0.275 * s * w, 0.005, 1.06), 0.046 * t * sleeve, 0.048 * t * sleeve),  # elbow
             ((0.275 * s * w, -0.01, 0.78), 0.034 * t, 0.030 * t),  # wrist
         ]
@@ -591,7 +594,7 @@ def _skin_body(spec):
     sub = obj.modifiers.new("Sub", "SUBSURF")
     sub.levels = 2
     dec = obj.modifiers.new("Decimate", "DECIMATE")
-    dec.ratio = 0.26
+    dec.ratio = 0.21
     dec.use_symmetry = True
     dec.symmetry_axis = "X"
     _apply_all(obj)
@@ -716,6 +719,102 @@ def _hair_cap(name, mat, front_z, back_z, radius=0.163, center=(0, 0.008, 1.645)
     return _finish(_link(name, bm), mat, smooth=True, sharp_angle=70)
 
 
+def _hair_curve(style):
+    """Hairline endpoints and skull offset for a hair style."""
+    if style == "buzz":
+        return 1.734, 1.608, 1.035
+    return 1.714, 1.588, 1.055
+
+
+def _trim_hidden_scalp(head, style):
+    """Delete the scalp that sits under the hair cap to free triangle budget.
+
+    The cap is a scaled copy of the skull, so any head face whose scaled
+    vertices all fall outside the hairline sphere is fully covered. Keeping
+    boundary-touching faces leaves a safety band under the hair rim; the open
+    hole is never visible and the accepted face geometry is untouched.
+    """
+    front_z, back_z, scale = _hair_curve(style)
+    center = Vector((0.0, 0.0, 1.665))
+    cutter_z = (front_z + back_z) * 0.5 - 0.396
+    bm = bmesh.new()
+    bm.from_mesh(head.data)
+
+    def covered(p):
+        q = center + (p - center) * scale
+        return (q.x * q.x + (q.y + 0.41) ** 2
+                + (q.z - cutter_z) ** 2) > 0.56 ** 2
+
+    doomed = [f for f in bm.faces if all(covered(v.co) for v in f.verts)]
+    if doomed:
+        bmesh.ops.delete(bm, geom=doomed, context="FACES")
+    loose = [v for v in bm.verts if not v.link_faces]
+    if loose:
+        bmesh.ops.delete(bm, geom=loose, context="VERTS")
+    bmesh.ops.recalc_face_normals(bm, faces=bm.faces)
+    bm.to_mesh(head.data)
+    bm.free()
+
+
+def _hair_from_head(source, style, mat_hair):
+    """Build the hair cap as a solid shell derived from the skull.
+
+    A separate hair ellipsoid cannot follow the broad MakeHuman crown, and an
+    open, face-deleted copy produces a sawtooth hairline. Scaling the closed
+    head shell outwards and boolean-cutting the face with a large front sphere
+    gives a watertight cap whose curved hairline is smooth from every angle.
+    """
+    front_z, back_z, scale = _hair_curve(style)
+    cap = source.copy()
+    cap.data = source.data.copy()
+    cap.name = "HairCap"
+    bpy.context.scene.collection.objects.link(cap)
+    center = Vector((0.0, 0.0, 1.665))
+    for v in cap.data.vertices:
+        v.co = center + (v.co - center) * scale
+    # The cutter is a big sphere in front of the face: its upper surface rises
+    # toward the brow and falls toward the nape, which is the hairline curve.
+    mid_z = (front_z + back_z) * 0.5
+    cutter_z = mid_z - 0.396
+    bpy.ops.mesh.primitive_uv_sphere_add(segments=32, ring_count=20, radius=0.56,
+                                         location=(0.0, -0.41, cutter_z))
+    cutter = bpy.context.object
+    bpy.context.view_layer.objects.active = cap
+    mod = cap.modifiers.new("Hairline", "BOOLEAN")
+    mod.operation = "DIFFERENCE"
+    mod.solver = "EXACT"
+    mod.object = cutter
+    bpy.ops.object.modifier_apply(modifier=mod.name)
+    bpy.data.objects.remove(cutter, do_unlink=True)
+    # The boolean result is still head-density. Hair needs silhouette, not
+    # pores, and the character budget has to stay under 16k triangles.
+    dec = cap.modifiers.new("HairReduce", "DECIMATE")
+    dec.ratio = 0.34
+    dec.use_collapse_triangulate = True
+    bpy.ops.object.modifier_apply(modifier=dec.name)
+    bm = bmesh.new()
+    bm.from_mesh(cap.data)
+    bmesh.ops.recalc_face_normals(bm, faces=bm.faces)
+    bm.to_mesh(cap.data)
+    bm.free()
+    cap.data.materials.clear()
+    cap.data.materials.append(mat_hair)
+    cap.data.shade_smooth()
+    cap.data.set_sharp_from_angle(angle=math.radians(55))
+
+    parts = [cap]
+    if style == "long":
+        parts.append(sphere("HairBack", 0.095, (0, 0.060, 1.560), mat_hair,
+                            seg=14, rings=9, scale=(0.98, 0.55, 1.55)))
+        for s in (-1.0, 1.0):
+            parts.append(sphere("Lock", 0.048, (0.089 * s, -0.012, 1.585),
+                                mat_hair, seg=8, rings=6,
+                                scale=(0.55, 0.85, 2.05)))
+    if style == "bun":
+        parts.append(sphere("Bun", 0.060, (0, 0.100, 1.775), mat_hair,
+                            seg=12, rings=8, scale=(1.0, 0.9, 0.95)))
+    return parts
+
 def _hair(style, mat_hair, broad=False):
     parts = []
     if style == "buzz":
@@ -1005,7 +1104,15 @@ def _makehuman_head(mats, spec):
                 target = remap.get(mat.name.split(".")[0])
                 if target is not None:
                     head.data.materials[index] = target
-        return [head]
+        # Bridge the 1.48-1.53 m neck gap between the MakeHuman cut and the
+        # procedurally built torso. The plug sits inside both shells, so only
+        # the visible band reads as neck and no seam ring reaches the surface.
+        plug = cyl("NeckPlug", 0.062, 0.052, 0.095, (0, 0.002, 1.500), skin,
+                   seg=12, scale=(1.10, 1.0, 1.0))
+        hair_style = "buzz" if spec["layer"] == "hood" else spec["hair"]
+        hair_parts = _hair_from_head(head, hair_style, hair)
+        _trim_hidden_scalp(head, hair_style)
+        return [head, plug] + hair_parts
 
     # The old decimated MakeHuman "hair" scalp slot reads as shaggy shards;
     # collapse the head to one skin slot so the join does not collide with the
@@ -1245,7 +1352,8 @@ def build_character(name, head="face"):
     else:
         head_parts = _face(mats, spec)
     hair_style = spec["hair"] if spec["layer"] != "hood" else "buzz"
-    head_parts += _hair(hair_style, mats["hair"])
+    if head != "mh":
+        head_parts += _hair(hair_style, mats["hair"])
     head = join(head_parts, "head")
     _auto_weights(head, layout, rigid=lambda p: "Head")
 
@@ -1811,10 +1919,10 @@ def build_prop(name):
 # Build + render entry points (inside Blender)
 # ---------------------------------------------------------------------------
 
-def _build_one(category, name):
+def _build_one(category, name, head="face"):
     reset_scene()
     if category == "npc":
-        objs = build_character(name)
+        objs = build_character(name, head=head)
     elif category == "npc_gear":
         objs = build_gear(name)
     else:
@@ -2764,6 +2872,9 @@ def main(argv=None):
     for cmd in ("build", "render"):
         s = sub.add_parser(cmd)
         s.add_argument("--only", default="")
+        if cmd == "build":
+            s.add_argument("--head", default="face", choices=("face", "proto", "mh"),
+                           help="character head source (default: face)")
     a = sub.add_parser("audit")
     a.add_argument("--json", action="store_true")
     fit = sub.add_parser("fit")
@@ -2854,7 +2965,10 @@ def main(argv=None):
                   file=sys.stderr)
             return 2
         for cat, name in _selected(args.only):
-            (_build_one if args.cmd == "build" else _render_one)(cat, name)
+            if args.cmd == "build":
+                _build_one(cat, name, head=args.head)
+            else:
+                _render_one(cat, name)
         if args.cmd == "build":
             results = [audit_asset(c, n) for c, n in catalogue()]
             write_manifest([r for r in results if r["vertices"]])