# Session handoff — 2026-08-03

Branch `claude/acdream-physics-divergence-5aa784`. `main` is still at `c7d5fc14`;
nothing here is merged. Complete Release suite green at **10,904 passed /
4 skipped / 0 failed** (session start: 10,844).

## What landed

| Commit | What |
|---|---|
| `9966b531` | **C4 route 2 — ForcePosition** through the canonical placement |
| `69ba9486` | Retail `@pklite` client command (`EnterPkLite` 0x028F) |
| `3ef61eb6` | Route 2 visual gate, rewritten with the real recipe |
| `d980456f` | Route 2 connected gate **user-accepted** |
| `e3b766d9` | Filed #297-#299 |
| `40f57213` | **Route 4 scoping — budget failed, stop and re-plan** |
| `88348f67` | **#299** mover-side `IsImpenetrable` exemption branch |
| `9b1e6fc6` | **#297** keep the PWD bitfield live so PK status reaches the client |
| `bc0077a5` | **#298** admit player targets to melee/missile attack and the camera |

## Needs your eyes (nothing below is user-verified)

Route 2 is accepted. These three are not:

1. **Collision with PKLite players** (#297). Both parties `@pklite`, walk into
   each other — you should now collide instead of phasing through. Then have
   them **equip or unequip something** and try again: that is the case round 1
   got wrong, and the fix is specifically about surviving it.
2. **Melee/bow on a PKLite player** (#298). Select them, attack. Should work
   now. Also confirm auto-target still refuses to acquire a player — pull a
   monster with a PKLite player nearby and check auto-target picks the monster.
3. **The combat camera** (#298). With `ViewCombatTarget` on (default), attacking
   a PKLite opponent should now track them. Retail gates the camera on the same
   predicate as the attack; we were using the narrow one.

Recipe for getting into PK Lite is in
[`2026-08-03-c4-route-2-visual-gate.md`](2026-08-03-c4-route-2-visual-gate.md).
Remember PK Lite is a **one-way** character state.

## The decision waiting for you: route 4

I stopped rather than starting it. After route 2 I pinned a falsifiable budget —
*if route 4 also costs ~900 production lines, the bet is dead* — and scoping came
back at **1,500-2,500 lines** plus ~1,700 lines of test re-modelling.

The seam generalises fine; route 2 just was not a representative unit (1 entity
vs N, 1 disposition vs 4, 1 execution path vs 2, 2 duplicate authorities vs 6).

**Recommendation: split route 4 into 4a and 4b.** 4a = near/interpolate +
airborne no-op — the observable win, no park hazard. 4b = teleport/far/cellless,
where the parks, the service-window guard, N3 and #277 all live.

Full analysis, including four findings that change the campaign plan (route 4's
Create half is already done; AP-131 cannot be retired by route 4; #277's safety
bound breaks; N3 stops being latent) is in
[`2026-08-03-c4-route-4-scoping.md`](2026-08-03-c4-route-4-scoping.md).

## Open follow-ups filed this session

- **#300** — `Properties.Ints[134]` vs `PublicWeenieBitfield` mirror gap.
- **#301** — retail's `OnStatUpdated` also rewrites radar blip colour and radar
  behaviour; acdream ignores both. #297 for the radar.
- **#302** — `PortalProjectionTests.ClipToRegion_FrameOwnedStore_ReusesExactResultArray`
  is flaky, ~1 run in 6, a `GC.GetAllocatedBytesForCurrentThread` assertion.
  **A green suite is not proof this is gone.**
- **#303** — `LiveEntityPvpBitfieldSync` is App-resident but touches only
  Runtime-owned state.
- **#304** — `SelectionInteractionController.GetSelectedOrClosestCombatTarget`
  has no production caller; one of #298's two widened call sites is dead code.
- **#305** — `HeadlessGameplayOperations` has #298's bug unpatched, so the
  graphical and headless hosts now diverge.

Register rows added: **AP-134** (the replicated PWD-bitfield coherence
invariant). **TS-23**'s retirement narrative corrected — it claimed since July
that every mover-flags site read the mover's "real" PK bits; the bits existed but
their source was frozen, so that only became true at #297.

## Process notes worth keeping

- **Four implementation passes and five review rounds on route 2, and every
  intermediate state was green** — 10,848, 10,853, 10,856, 10,858. The suite
  caught none of the four real defects. Two of them were introduced *by* the
  fixes for the other two.
- **Demanded regression tests found root causes that review missed.** #297's
  "assert the flags survive an appearance rebuild" test is what exposed the
  second snapshot store.
- **Three false claims reached documentation and were retracted before
  commit** — a "retail fidelity gain" that was a fixture artifact, an
  acceptance-coverage claim in the cutover plan, and an IA-19 citation covering
  a divergence it does not reach. Each would have become the thing a future
  session trusted.
- **Go to the bytes when the decompiler is ambiguous.** #299 turned on whether
  `if (state_1 < 0)` was a 0x80 or 0x8000 test; decoding the PDB-paired binary
  settled it (`test al,al; js`).