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+# BLOBBO Workshop — custom assets + in-game editor (plan, 2026-07-18)
+
+**Goal:** John designs/builds models (Blender, or farm-generated GLB) and drops
+them into the live game without touching code — plus an in-browser editor to
+preview, fit, and export the mapping.
+
+## Why this is easy here
+Physics and visuals are fully decoupled: every collider is a primitive; every
+mesh is cosmetic. Swapping a mesh can never break gameplay. The ONE special
+case is the blobbo body — the paint system stamps into a canvas texture through
+the mesh's UVs — so a custom blob needs clean, non-overlapping UVs and its
+material's `map` slot handed to `PaintSkin`.
+
+## Reskinnable slots (the inventory)
+| Slot id | Today | Notes |
+|---|---|---|
+| `blob.body` | UV sphere | PAINTABLE — needs clean UVs; SkinnedMesh OK (idle/wobble clip plays via mixer; squash still applies at group level) |
+| `blob.face` | procedural googly eyes | separate from paintable body, by design |
+| `ghost.body` | translucent blob copy | auto-derived from blob.body (desaturated) |
+| `cannon.base` / `cannon.barrel` | cylinders | per-colour tint applied on top |
+| `machine.plate` | box + base | pressure plate |
+| `machine.boot` | boot+spring primitive | farm GLB already exists (`assets/meshes/prop-spring-boot.glb`) |
+| `machine.bucket` | cylinder shell + fill | farm GLB exists (`prop-paint-bucket.glb`) |
+| `machine.arch` | frame + bubbles | bubble cleanser |
+| `machine.belt` | striped box | conveyor |
+| `course.scenery.*` | giant boxes (cereal box etc.) | free-place decorative slots; toaster GLB exists |
+| `course.tramp` | orange pad | gap launcher |
+| `course.tunnel` | slab + posts | MINI tunnel |
+| `course.finish` | pink podium | finish pad |
+| `fx.puddle` | flat glossy slab | material/decal upgrade slot |
+| UI: title wordmark, HUD | CSS/DOM | swap via CSS/vars, out of scope for v1 |
+
+## Architecture (two lanes + integration)
+
+### Lane I — Asset runtime (`src/assets/`)
+`assets/manifest.json` maps slot → `{url, offset, rotation, scale, options}`.
+`AssetRegistry` (GLTFLoader + cache) resolves slots; **every construction site
+falls back to today's procedural primitive when a slot is empty or fails to
+load** — an empty manifest must produce today's game, byte-for-byte behavior.
+Construction sites (createBlob, cannon barrel, machine parts, greybox scenery)
+ask the registry instead of building directly, via a tiny `slotMesh(world,
+'machine.boot', buildProcedural)` hook. Blob slot additionally: UV sanity check
+(warn if overlapping/absent), PaintSkin adoption of the delivered material, and
+optional AnimationMixer for a named idle clip. Local override layer:
+manifest + GLB blobs can live in IndexedDB (set by the editor) and take
+precedence — so custom assets are playtestable on the LIVE site with zero deploys.
+
+### Lane J — Workshop editor (`/editor.html`, `src/editor/`)
+A separate page sharing the game's modules. Three panels:
+1. **Slots** — every slot with live thumbnail; click to select.
+2. **Stage** — the actual game world (greybox + machines idling) rendering the
+   current assets; orbit camera; selected slot highlighted.
+3. **Fit** — drag-drop a `.glb` from disk onto a slot → instant swap in the
+   stage; sliders/inputs for offset/rotation/scale; paintability report for
+   blob.body (UV coverage, tri count, material count); "Test drive" button
+   boots the REAL game in-page with overrides active.
+Export: ⬇ `manifest.json` download + "Save locally" (IndexedDB override, with a
+persistent "custom assets active — clear?" pill in the game). No server writes:
+committing an asset pack = John drops the GLB in `assets/live/` + manifest in
+the repo (documented in the panel's "ship it" help text).
+
+### Integration (main session)
+Wire registry into game.ts construction, ship `/blobbo/editor.html`, verify
+(empty-manifest parity, toaster GLB in a scenery slot, blob swap with the farm
+mesh incl. paint), deploy. Ship the 4 existing farm GLBs as the first pack.
+
+## Blender/authoring conventions (put in the editor's help panel too)
+- Y-up, -Z forward, meters; blob body ≈ 1.0u diameter, origin at CENTER;
+  props origin at ground-contact center. Single material preferred.
+- Paintable blob: one UV island set, no overlaps, no mirrored UVs.
+- Rigged: single armature, clips named `idle` (loop) and optionally `roll`;
+  keep ≤ ~40 bones (mobile later). GLB embedded textures ≤2048².
+- Licensing per asset-pipeline skill: 🟢 web-ok only (farm-generated = ok).
+
+## Out of scope v1 (candidate wave 4)
+Course layout editing (move/add machines, puddles, boxes → course JSON),
+animation retarget beyond idle clips, multi-pack management, shared packs.
diff --git a/lanes/LANE-I-asset-runtime.md b/lanes/LANE-I-asset-runtime.md
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+# Lane I — Asset runtime (manifest, registry, slot hooks)
+
+**Owns:** `src/assets/`, `assets/manifest.json`, `demos/lane-i.html`,
+`src/demo/lane-i.ts`, PLUS surgical slot-hook edits inside `src/blob/createBlob.ts`,
+`src/paint/cannon.ts` (barrel build only), `src/machine/parts.ts` (mesh builds
+only), `src/course/greybox.ts` (scenery only). Those four are OTHER lanes' files:
+your edits there must be strictly additive-visual — replace direct mesh
+construction with a registry hook that DEFAULTS to the existing construction.
+Never touch physics/colliders/logic in them, and never edit contracts/world/
+game/main/package.json.
+
+## Mission
+Custom GLB assets drop into named slots without code changes; an empty manifest
+produces today's game exactly. See docs/WORKSHOP-PLAN.md for the slot table —
+implement every slot listed there except the UI rows.
+
+## Deliverables
+1. `src/assets/manifest.ts` — schema + loader:
+   ```ts
+   interface SlotEntry { url: string; offset?: [n,n,n]; rotationDeg?: [n,n,n];
+     scale?: number | [n,n,n]; idleClip?: string }
+   type Manifest = Record<SlotId, SlotEntry>
+   ```
+   Load order (later wins): `assets/manifest.json` (fetch, may 404 → {}) →
+   IndexedDB override (`blobbo-workshop` db: `manifest` + `blobs` stores; GLB
+   entries may be `idb:<key>` urls resolved to object URLs).
+2. `src/assets/registry.ts` — `AssetRegistry`:
+   - `slotObject(slot, buildFallback: () => THREE.Object3D): THREE.Object3D` —
+     synchronous placeholder pattern: returns a Group immediately containing the
+     fallback; if the manifest has the slot, async-load the GLB (GLTFLoader from
+     `three/examples/jsm` — already in the three package, no new deps), then
+     swap the group's child in place, applying offset/rotation/scale.
+   - Cache by url (clone via `SkeletonUtils.clone` for skinned, `.clone()` else).
+   - Load failure → keep fallback + one console.warn (never throw).
+   - `paintableInfo(object)` — for blob.body: find first Mesh/SkinnedMesh,
+     report { uvOk (uv attr exists & 0..1 bounded), triCount, materialCount }.
+3. Blob slot specifics (in your createBlob hook):
+   - The delivered mesh's material `map` is replaced by PaintSkin's canvas
+     texture at integration (skin binds to whatever mesh is present); ensure
+     the hook exposes the swapped-in paintable mesh as `blob.mesh` (the skin
+     and buffs read it). If the GLB is a SkinnedMesh with `idleClip`, drive an
+     AnimationMixer in a fixed-step System (NOT onFrame — hidden-tab rule, see
+     telegraph.ts docstring for why).
+   - UV warning: if `paintableInfo.uvOk` is false, console.warn and keep the
+     procedural sphere instead (paint must never silently break).
+4. `assets/manifest.json` — ship EMPTY `{}` (packs come later via integration).
+5. Demo `demos/lane-i.html` + `src/demo/lane-i.ts`: a stage that builds every
+   slot twice — fallback vs a test manifest pointing at the four existing farm
+   GLBs (`assets/meshes/*.glb`) — side by side, with per-slot load status text
+   and the paintability report for blob.body.
+
+## Acceptance
+- `npm run build` green. With `{}` manifest: pixel-identical construction paths
+  (verify: no registry code path alters any existing geometry parameters —
+  the fallback builders are the ORIGINAL code moved, not rewritten).
+- Demo loads all four farm GLBs into sensible slots (boot, bucket, toaster
+  scenery, blob body) with fit transforms committed in the demo's test manifest.
+- Blob body swap: paint stamps visibly land on the swapped mesh in the demo
+  (drive a scripted splat at a known point).
+- Failure paths: bad url → fallback + single warn; malformed manifest → `{}`.
+- Slot-hook edits to the four foreign files are mesh-construction-only (diff
+  must show no collider/physics/logic lines changed).
+
+## Contract friction
+Report, never edit frozen files. If a slot needs data the hook can't reach,
+document it for integration rather than widening interfaces.
diff --git a/lanes/LANE-J-workshop-editor.md b/lanes/LANE-J-workshop-editor.md
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+# Lane J — Workshop editor (drop-in asset fitting + export)
+
+**Owns:** `src/editor/`, `editor.html` (repo root, sibling of index.html),
+`demos/lane-j.html`, `src/demo/lane-j.ts`.
+**Never touches:** contracts, world, game, main, package.json, other lanes'
+dirs. Depends on Lane I's `src/assets/` API (manifest.ts, registry.ts) — it
+runs in a parallel worktree, so code against the INTERFACES specified in
+lanes/LANE-I-asset-runtime.md §Deliverables 1-2 exactly; integration reconciles.
+No new deps (GLTFLoader ships inside three).
+
+## Mission
+A browser page where John drags his own GLB files onto game-object slots, fits
+them (offset/rotation/scale), sees them ON the real course, saves them locally
+so the LIVE game uses them instantly, and exports a manifest for committing.
+docs/WORKSHOP-PLAN.md is the product spec — read it first.
+
+## Deliverables
+1. `editor.html` + `src/editor/main.ts` — three-panel layout (CSS grid, no framework):
+   - **Slots panel (left):** every slot from the plan's table with status
+     (procedural / custom / override-active). Click selects.
+   - **Stage (center):** the greybox course + idle machine visuals (import the
+     real builders; physics optional — a static scene is fine, but reuse real
+     meshes so fits are truthful). OrbitControls (three/examples/jsm). Selected
+     slot's object gets an outline/pulse. Camera-focus button per slot.
+   - **Fit panel (right):** for the selected slot — drop zone ("drop .glb"),
+     numeric inputs + sliders for offset xyz / rotation xyz / uniform scale,
+     reset-to-procedural button, and for `blob.body` the paintability report
+     (uvOk / tris / materials) with a red warning banner when uvOk=false.
+2. Drag-drop flow: File API → store blob in IndexedDB (`blobbo-workshop`/`blobs`),
+   manifest entry url `idb:<key>` → registry hot-swaps the stage object live.
+3. **Save locally** — writes the working manifest to the IndexedDB override the
+   game reads (Lane I load order). **Export** — downloads `manifest.json`
+   (idb urls flagged with a "commit the .glb files to assets/live/ and change
+   urls" note in the download's `_readme` field). **Clear overrides** button.
+4. **Test drive** — button that opens `/blobbo/` in a new tab (overrides are in
+   IndexedDB, so the live game picks them up — say so in the UI).
+5. Ship-it help card: Blender conventions from the plan doc + "to make it
+   permanent: assets/live/ + manifest.json + redeploy".
+6. Demo `demos/lane-j.html`: the editor booted with a scripted fake-drop of
+   `assets/meshes/prop-spring-boot.glb` onto `machine.boot` (fetch → same code
+   path as a real drop), asserting the stage object swapped and the exported
+   manifest round-trips.
+
+## Acceptance
+- `npm run build` green (editor.html added to YOUR OWN vite input? NO — you
+  can't edit vite.config.ts; note it as friction, integration adds the input).
+- Demo's scripted drop swaps the stage mesh and the export round-trips
+  (parse the downloaded JSON blob in-page and deep-equal it).
+- Fit controls visibly transform the object; values persist through slot
+  switches; reset restores procedural.
+- blob.body drop with the farm blobbo GLB shows the paintability report.
+- Overrides survive reload (IndexedDB), and Clear removes them.
+- Zero console errors on an empty session (no drops, all procedural).
+
+## UX bar
+This is John's tool: label everything in plain words, no dev jargon on screen.
+It should feel like a toy, not an IDE — big drop targets, instant feedback,
+one obvious happy path (pick slot → drop file → nudge sliders → Save locally →
+Test drive).