# SIDE B — Lane S: dust bunnies, portal FX, HUD stamp tray

Read `docs/briefs/SIDEB.md` + `src/core/worlds.ts` first. You own
**`src/fx/**` and `src/ui/**`** — NOT `src/net/Avatars.ts` (the SOCIAL_RESET
phase owns avatars/emotes now; `docs/briefs/SOCIAL_RESET.md` is required
reading so you don't duplicate its FX). Consume bus events only — never
import Lane M/W code.

## S1. Dust bunnies (fx critters, purely cosmetic)

3–4 fist-sized fluff-balls (procedural: a tiny THREE group of 8–12 grey
dust-tone quads, jittered) drifting around the under-table PCB floor (y≈3).
Keep-out zones: the three portal rings (`WORLD_DEFS[k].portalStand` ±6) and
the parts-bin/fuse quest spots. Wander slowly; flee 8 voxels when the player
comes within 5 (ease out, never through walls — sample `world.isSolid` ahead);
settle again. No colliders, no game effect. Emit
`machine:interact {action:'bunny_flee'}` at most 1/s when spooked (Lane E2
squeaks). Budget: zero steady-state allocations, no fps regression.

## S2. Portal + stamp FX

- `world:enter`: 400 ms vinyl-warp iris — full-screen overlay of concentric
  groove rings collapsing to black, accent-tinted per world
  (`WORLD_DEFS[k].accent`); release on arrival. `world:exit`: reversed.
  (Coexist with the first-visit flythrough's cine override — never fight the
  camera; you're a screen overlay only.)
- `stamp:got`: confetti burst (reuse the FxSystem burst pattern) + HUD toast
  via the tray (S3).
- `stamp:all`: golden shimmer — a brief booth-wide emissive pulse via the
  existing `setEmissiveBoost` path, plus gold confetti at the crate.

## S3. HUD stamp tray

Small tray top-right under the signal lamps: three record-stamp dots
(accent-coloured when got, dim ring when not), scale-pulse on `stamp:got`,
gold ring on `stamp:all`. Initial state comes from replayed `stamp:got`
events on join (Lane M re-emits from the join snapshot — coordinate exact
timing via handoffs).

## Verify + handoff

Typecheck clean; exercise in the real game (`turncraft-laneE-verify` launch
config) — bunnies wander/flee with zero console errors and measured fps
unchanged; portal iris and tray driven by hand-emitted bus events. Handoff:
`docs/SIDEB_S_handoff.md`.