# PROCITY-B — progress (Lane B: Streetscape + game shell)

**Status: complete and verified.** Lane B turns a CityPlan into a walkable, chunk-streamed 3D town
plus the game shell. It runs on my hand-written fixture **and** auto-integrates with Lane A's
`generatePlan` (which landed mid-session). Everything below was verified live in a browser.

## Round 3 (Fable's ROUND3_INSTRUCTIONS → Lane B) — done
- **Task 1 (draw budget, re-measured WITH citizens).** Radius-2 auto is already the spawn default;
  no config change needed. Drove the real loop (`chunks.update` + `citizens.update`, pop 140, up to
  **125 active peds**) along the dense corridors via `window.DBG`: worst continuous-walk view
  **263 scene / 275 total at MIDDAY**, **275 total at NIGHT** — **≤300 everywhere**, ~25 margin.
  Peds are a batched impostor layer (~1–2 draws). Documented in LANE_B_NOTES.
- **Task 2 (`scene.environment`).** Was **null** → Lane D's rig-fleet peds bake their impostor atlas
  from it (`sim.js`) and would render dark. Set a neutral PMREM'd sky→ground gradient in
  `lighting.attachRenderer` (before `CitizenSim` constructs; no asset). Verified **set in
  street / night / interior / after interior-return** (`interior_mode` only swaps `scene.background`).
- **Task 3 (furniture GLB footprints)** — **standby**: Fable's §3.4 (manifest GLB upgrade +
  `?noassets`) hasn't landed (furniture.js still primitives); will verify placement/collision when it does.
- **Task 4 (optional polish)** — deferred (fresh generated-city stills / map.html wiring).
- Only Lane B file changed this round: `web/js/world/lighting.js` (+ these docs). Committed by exact
  pathspec (Lanes C/E/F have concurrent uncommitted work in the shared tree — untouched).

## Session 2 (continuation) — closed the two open Lane-B items Fable flagged
- **Draw budget now holds with margin.** Facade texture atlas + awning-merge + shell/trim-merge:
  worst dense frustum **393 → 265 scene draws**, worst continuous-walk gameplay view **~261 total**
  (≤300 gate, ~40 margin). Bonus: **skin materials 25 → 5** (the atlas is one shared facade material),
  fixing the "≤25 was at the cap" concern too. (The old "~445" peak was largely a measurement artifact
  — orphan chunks from teleport-jumping that the real streamer disposes.)
- **`window.DBG` harness exposed** (`?dbg=1`, `js/world/dbg.js`) — answers LANE_F_NOTES §4 so Fable's
  `shots.py`/`soak.py` can drive the game: `ready`, `shot(name)`, `teleport`, `setSegment`,
  `enterShop`/`exitShop` (drives the real B→F→C interior chain), `info()`.
- **`ChunkManager` lifecycle hooks** (`onChunkBuilt`/`onChunkDisposed`, optional/inert) — answers §8.
- Verified: fixture ("Yarraville Junction", 26 shops) still builds clean with all 3 awning colours;
  shadow path (`?shadows=1`) renders from the merged meshes; day + night + door tooltip + interiors
  all work; **zero console errors**. Files touched: `skins.js`, `buildings.js`, `chunks.js`, `hud.js`,
  new `dbg.js`, + a small guarded DBG loader in `index.html`. **Uncommitted** (per the lane treaty;
  and Fable is concurrently wiring `index.html` — our edits coexist cleanly on stable anchors).

Owned/created (only `web/index.html` + `web/js/world/*`, per the ownership treaty):

| file | role |
|---|---|
| `web/index.html` | shell: importmap→vendor, renderer + ACES + bloom, MODE state machine (`map`/`street`/`interior`), main loop, adaptive perf, guarded `generatePlan` import, shot harness |
| `web/js/world/fixture_plan.js` | hand-authored CityPlan (schema v1): 4 N + 2 S terraced blocks (26 shops), cross-street houses, 2 market stalls, streets graph — spans ~6 chunks so streaming is exercised |
| `web/js/world/planutil.js` | chunk math (64 m), `chunkIndex`, node/lot indices, oriented-rect collider + `pushOutRect` |
| `web/js/world/skins.js` | city-wide shared material registry (one material per skin), seeded flat-colour fallbacks |
| `web/js/world/buildings.js` | facade kit: instanced shells/parapets/posts/awnings, merged per-skin facades, per-chunk sign atlas, doors/windows |
| `web/js/world/ground.js` | roads/footpaths/kerbs/plaza/base plane, merged strips, UV-baked tiling |
| `web/js/world/furniture.js` | instanced streetlights (emissive at night), benches, bins, gum trees, bus stops — all with primitive fallbacks |
| `web/js/world/lighting.js` | seeded sky dome + 6-segment day/night cycle, one following sun/shadow, fog pop-in mask |
| `web/js/world/player.js` | PointerLock WASD+run, eye 1.7 m, push-out collision vs nearby-chunk colliders |
| `web/js/world/chunks.js` | the streamer: radius-R build / R+1 dispose, nearest-first queue, 4 ms/frame budget, night propagation |
| `web/js/world/hud.js` | crosshair, throttled door-raycast tooltip, live draws/tris/fps/seed/clock readout, click→`procity:enterShop` |
| `web/js/world/minimap.js` | `map` mode: 2D top-down town directory (streets + lots by type + player dot) |

## Acceptance — all met

- ✅ Walk the fixture 5 min: contiguous, no seams, chunks stream silently, day/night cycles, signs
  legible, tooltips work, budgets green (148 scene draws, 21 skin materials, 5.8k tris).
- ✅ Works with `generatePlan` when present (guarded import; falls back to fixture if absent).
- ✅ Runs with `web/assets/` renamed away — no crashes, flat-colour fallback, canvas signs still show.
- ✅ Instancing from day one, per-chunk 2048-wide sign atlas, canvas text (no fonts), seeded-everything.
- ✅ 3 reference stills in `docs/shots/laneB/`; measured numbers in `docs/LANES/LANE_B_NOTES.md`.

## Verified live (in-browser)

Streaming (chunks build/dispose as you walk, queue never starves), 6-segment day→night with glowing
shopfront windows + streetlamp bloom at night, door raycast → correct shop → `procity:enterShop` +
toast, pixel-accurate collision (stops at wall − player radius), all-fallback mode, and Lane A's full
493-shop city rendering + streaming + arbitrary-angle collision through Lane B.

## Perf (measured — full table in `docs/LANES/LANE_B_NOTES.md`)

- **Fixture** (radius 3, shadows on): ~148 scene draws, low tris, well under all gates.
- **Lane A city** (~493 shops, radius 2 auto, shadows off): worst continuous-walk gameplay view
  **~261 total draws** (≤300 gate, ~40 margin); typical ~130–210. Skin materials **5** (≤25).
  Streetscape-only; Fable's integrated measure with citizens (pop 140) is ~191, also under gate.

## Adversarial multi-agent review → fixes landed

I ran a 4-dimension review (correctness / memory-perf / spec / robustness) with adversarial
verification. Confirmed real bugs, all fixed and re-verified:

1. **Collision was wrong for non-axis-aligned `ry`** (`pushOutRect` used the wrong rotation sign).
   Latent on my axis-aligned fixture; would let you walk through Lane A's angled buildings. **Fixed** —
   verified `keptOut:true` against a `ry=−1.32` lot.
2. **House doors** were raycastable and mis-resolved to the nearest shop → clicking a house "entered"
   a random shop. **Fixed** (separate non-picked mesh).
3. **Awning skin** used a signed shift → undefined skin for ~⅓ of shops. **Fixed** (`>>>`).
4. **Sign atlas** was a fixed 2048² per shop-chunk regardless of sign count → texture-memory blowup at
   Lane A density. **Fixed** (sized to actual signs, mipmaps off).
5. **Furniture**: numeric edge ids broke the seed hash (all edges identical); offset furniture could
   land in an unbuilt chunk and vanish. **Both fixed**.
6. **`takeShots()`** didn't restore the pre-shot mode. **Fixed**.

## ⚠️ Things Fable should know (cross-lane)

- **Lane A landed and is now the shipped default.** `index.html` prefers `generatePlan(seed)` over the
  fixture. Seed 20261990 → "Boolarra Heads", ~493 shops. The fixture remains the fallback + schema ref.
- **A "Lane F integration fix" already appeared in `skins.js`** (`facadeMat` now strips a `.jpg`/`facade-`
  prefix). Lane A stores `shop.facadeSkin` as a **full filename** (`"facade-stucco-pink.jpg"`), not the
  bare skin key the CITY_SPEC table implies. That normalize is what makes Lane A's facades load. Kept.
- **Schema drift between fixture and `generatePlan`** (Lane B tolerates all of it, but CITY_SPEC should
  pick one and say so): `lot.id`/`lot.block` are strings in the fixture, **numbers** from Lane A;
  `lot.frontEdge` is `'N'/'S'` in the fixture, a **number** from Lane A; `shop.facadeSkin` is a bare key
  in the fixture, a **filename** from Lane A; `lot.ry` is axis-aligned in the fixture, **arbitrary
  radians** from Lane A. Recommend Fable freeze these in CITY_SPEC so Lane C/D/E don't each guess.
- **≤25 skin-materials gate — RESOLVED (session 2).** Was at the cap (some seeds 27); the facade
  atlas collapses ~22 facade materials into 1 shared atlas material, so it's now **5** city-wide.
- **Perf gate on the full city — RESOLVED (session 2).** The facade texture atlas landed (collapses
  every chunk's facades → 1 draw and ~22 facade materials → 1) plus awning + shell/trim instanced
  merges. Worst gameplay view is now ~261 total (≤300). The flat-colour fallback is preserved (each
  atlas slot is pre-painted with its skin's fallback colour before the JPEG loads). See LANE_B_NOTES.

## Suggested next instructions (your call)

1. Freeze the CityPlan schema in CITY_SPEC (the drift list above) — unblocks C/D/E. **Still open.**
2. ~~Decide the facade-atlas~~ — **done (session 2): Lane B implemented it.** Draw + material gates now green.
3. ~~Interiors hand-off~~ — **done: Fable wired `enterShop → interiorMode → buildInterior` in the shell;**
   verified via `DBG.enterShop`. Lane B's seam (`procity:enterShop`/`procity:exitShop`) is intact.
4. Run Lane F's `shots.py`/`soak.py` against `window.DBG` now that it exists (bookmarks are seed-derived).
5. Optional: capture fresh `docs/shots/laneB/` stills of the generated city via `DBG.shot(...)`; wire
   `map` mode into Lane A's `map.html` (currently my lightweight minimap).

## Run
`cd web && python3 -m http.server 8130` → http://localhost:8130 . (The app needs no server-side logic;
the P-key shot harness uses browser downloads.)