Two retail divergences fixed from the 2026-05-16 faithfulness audit
(Commit A of the plan at docs/superpowers/plans/2026-05-16-retail-faithfulness-fixes.md).
1. Rotation rate ignored HoldKey.Run. Retail's CMotionInterp::
apply_run_to_command (decomp 0x00527be0 line 305098) multiplies
turn_speed by run_turn_factor (1.5, PDB-named symbol at 0x007c8914)
when input is TurnRight/TurnLeft under HoldKey.Run. Effective
running rotation is 50% faster (~135°/s vs walking ~90°/s).
Our keyboard A/D and ApplyAutoWalkOverlay used a fixed walking
rate.
New: RemoteMoveToDriver.TurnRateFor(running) helper. Keyboard
path passes input.Run; auto-walk overlay passes
_autoWalkInitiallyRunning. The walking-rate base
(BaseTurnRateRadPerSec = π/2) is unchanged; TurnRateRadPerSec
constant is preserved as the walking-rate alias for callers
that don't have run/walk state (NPC remotes).
2. IsUseableTarget gated on `useability & USEABLE_REMOTE (0x20)`,
which was stricter than retail. Per ItemUses::IsUseable
(acclient_2013_pseudo_c.txt:256455) cross-referenced with 4
call sites, retail's IsUseable() semantic is `_useability != 0`.
But visually retail's USEABLE_NO (1) entities don't approach
either, because ACE never broadcasts MovementType=6 for them.
Our client installs a speculative auto-walk BEFORE the server
responds, so we'd visibly approach + face signs before the
wire packet was rejected.
Pragmatic fix: block USEABLE_UNDEF (0) AND USEABLE_NO (1) in
IsUseableTarget — slightly stricter than retail's
IsUseable but matches retail's user-visible behaviour
("R on sign does nothing"). Documented in the doc-comment so
a future implementer knows the gap.
3. New IsPickupableTarget gate for F-key path — requires
USEABLE_REMOTE (0x20) bit. Null-useability fallback for
BF_CORPSE + small-item ItemTypes (preserves M1 ground-item
pickup flow when ACE seed DB doesn't publish useability).
4. R-key (UseCurrentSelection) upfront gate now ALWAYS uses
IsUseableTarget. R is conceptually "use" with smart-routing
to pickup as a downstream optimization. F-key (SendPickUp)
uses IsPickupableTarget directly.
5. Retail toast strings on block, centralised in new
src/AcDream.Core/Ui/RetailMessages.cs:
- "The X cannot be used" (data 0x007e2a70, sprintf 0x00588ea4)
fires on UseCurrentSelection / SendUse gate block.
- "The X can't be picked up!" (sprintf 0x00587353) fires on
SendPickUp non-pickupable block.
- "You cannot pick up creatures!" (data 0x007e22b4) fires on
SendPickUp creature block (was previously silent).
- Plus 4 inactive retail strings ready for future call sites:
CannotBeUsedWith (two-target Use), CannotBePickedUp (formal
pickup variant), CannotBeUsedWhileOnHook_HooksOff +
CannotBeUsedWhileOnHook_NotOwner (housing). All cite their
retail data addresses + runtime sprintf addresses.
6. ProbeUseabilityFallbackEnabled diagnostic (env var
ACDREAM_PROBE_USEABILITY_FALLBACK=1) logs every time the
null-useability fallback fires. Settles whether the
fallback for creature + BF_DOOR/LIFESTONE/PORTAL/CORPSE
entries in ACE's seed DB without useability is hot code
or theoretical defense.
Test coverage:
- +3 RemoteMoveToDriverTests cover TurnRateFor walking/running/back-compat.
- +7 RetailMessagesTests cover each retail string with retail anchor.
- +1 CreateObjectTests TryParse_WeenieFlagsUsable_ReadsUseableNoValue
pins parser correctness for USEABLE_NO=1.
- 294/294 Core.Net pass; 24/24 new+touched Core tests pass.
- Pre-existing baseline of 8 Physics test failures unchanged
(BSPStepUp + MotionInterpreter regression noise from prior
sessions; out of scope here).
Deferred to a separate session per user direction:
- Click area = indicator-rect retail fidelity. Retail's picker
uses per-part CGfxObj.drawing_sphere + polygon refine
(0x0054c740); ours uses single Setup.SelectionSphere ray-
intersect. The rect corners are dead zones today. Three fix
options analyzed: screen-space rectangle hit-test, sqrt(2)
sphere inflation, polygon refine Stage B.
Plan: docs/superpowers/plans/2026-05-16-retail-faithfulness-fixes.md
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Per the B.6 design spec (now retail-grounded on Option A), slice 1 is
pure-additive logging so the next session has a clean trace of what
ACE actually sends to the local player during a server-initiated
auto-walk.
New PhysicsDiagnostics.ProbeAutoWalkEnabled static flag, env-var-
initialized from ACDREAM_PROBE_AUTOWALK=1. Probe sites:
[autowalk-out] on SendUse + SendPickUp — the packets that trigger
ACE's CreateMoveToChain when the target is out of WithinUseRadius.
[autowalk-mt] on OnLiveMotionUpdated for _playerServerGuid only —
captures MovementType + MoveToPath origin/min-dist/obj-dist +
moveTowards + speed/runRate. Lets us see exactly the wire data
retail's PerformMovement case 6 (0x00524440) was acting on.
[autowalk-up] on OnLivePositionUpdated for _playerServerGuid only —
cadence + payload of ACE's position broadcasts during auto-walk.
No behavior change. All flags off by default; opt in with the env var
during a focused reproduction. Designed to be mirrored into DebugVM
checkbox state later (parallel to ProbeResolve / ProbeCell / ProbeBuilding)
but not wired yet — env-var-only for the first trace session.
Adds ACDREAM_PROBE_BUILDING — a read-only per-shadow-entry probe that
captures full BSP collision evidence whenever TransitionTypes.FindObjCollisions
attributes a hit (via the existing L.2a slice 3 chain). One multi-line
[resolve-bldg] entry per attributed hit: partIdx, hasPhys, bspR vs
vAabbR, world-space entOrigin_lb, and the actual hit polygon's vertices
in both object-local and world space.
Paired with a one-time [entity-source] line at every ShadowObjects.Register
call site in GameWindow so entityId from a probe line is greppable to its
WorldEntity source within a single log file.
Plumbing: BSPQuery writes the resolved hit polygon to a new
PhysicsDiagnostics.LastBspHitPoly side-channel at the 5 SetCollisionNormal
sites in Paths 5/6 + CollideWithPt. TransitionTypes clears that field
before each shadow-entry dispatch and reads it back at the L.2a slice 3
attribution site to emit the probe line.
Spec component 4 originally described an out ResolvedPolygon? parameter
on BSPQuery.FindCollisions; the static side-channel achieves the same
observable behavior without plumbing through BSPQuery's recursive private
methods. Deviation noted in PhysicsDiagnostics.LastBspHitPoly's XML doc.
Reframes the plan-of-record's L.2d sub-direction paragraph: the 2026-05-12
handoff proposed porting CBuildingObj + per-cell walkability, but ACE
BuildingObj.cs:39-52 + named-retail acclient_2013_pseudo_c.txt:701260
show find_building_collisions is one BSP test on Parts[0]. Per-cell
walkability belongs to L.2e, not L.2d. L.2d slice 1 is the diagnostic;
slice 2 is the actual fix scoped from slice 1's evidence (one of three
hypotheses: wrong BSP loaded / over-registered parts / BSPQuery flaw).
Tests: 2 synthetic unit tests in PhysicsDiagnosticsTests.cs pin the
static API contract that the BSPQuery → side-channel → TransitionTypes
emission chain depends on. The multi-line line format itself is verified
by acceptance criterion 2 (live Holtburg-doorway capture) — covering it
here would require a heavy PhysicsEngine + Transition fixture for a
diagnostic-only emission.
Verified: dotnet build green; the 2 new tests pass; the 8 pre-existing
test failures listed in the L.2a handoff (MotionInterpreter GetMaxSpeed_*,
PositionManager.ComputeOffset_BothActive_Combined,
PlayerMovementController.Update_ForwardInput_*, Dispatcher.W_held_*,
BSPStepUpTests.{D4,C3}) remain failing — none introduced by this slice.
Spec: docs/superpowers/specs/2026-05-13-l2d-cbuildingobj-collision-design.md
Conformance anchors:
- acclient_2013_pseudo_c.txt:701260 (CBuildingObj::find_building_collisions)
- acclient_2013_pseudo_c.txt:323725 (BSPTREE::find_collisions)
- ACE references/ACE/Source/ACE.Server/Physics/Common/BuildingObj.cs:39-52
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
New static `AcDream.Core.Physics.PhysicsDiagnostics` holds two
runtime-toggleable flags initialized from env vars:
- ACDREAM_PROBE_RESOLVE=1 — emit one [resolve] line per
PhysicsEngine.ResolveWithTransition call: input/target/output
position+cell, ok-vs-partial, grounded-in, contact-plane status,
wall normal if hit, walkable-polygon valid, moving entity id.
- ACDREAM_PROBE_CELL=1 — emit one [cell-transit] line per
PlayerMovementController.CellId change: old → new cell, current
world position, reason tag (resolver / teleport).
Both also exposed as runtime-toggleable checkboxes in the DebugPanel
"Diagnostics" section. Unlike the existing four Dump-* checkboxes
(which only mirror sticky-at-startup env vars), the two new ones
forward directly to PhysicsDiagnostics — toggling on/off takes
effect on the next physics resolve, no relaunch.
Why now: L.2's plan-of-record (docs/plans/2026-04-29-movement-collision-
conformance.md) explicitly says "Land L.2a diagnostics first. Do not
make another physics change blind." This slice closes the most-load-
bearing gap in L.2a — a general-purpose probe on the resolver outcome
and a cell-transit log — so that later L.2b/c/d/e physics changes can
be evidence-driven instead of guessed. Foundation for the indoor /
dungeon walking trajectory (G.3 unblock).
Pure additive: when both flags are off (default), the probes collapse
to a single static-bool read per resolve, zero log cost. PlayerMovement
Controller's two CellId-mutation sites are now routed through a
private UpdateCellId(reason) helper for diag chokepoint.
Build green, 1032/1040 unit tests pass. The 8 failing tests are
pre-existing on the branch base (verified by stash-and-rerun);
none touch resolver or cell-transit code; all fail identically with
this slice stashed. Investigation deferred to a follow-up.
Refs: docs/plans/2026-04-29-movement-collision-conformance.md (L.2a
shipped-slice note added in same commit).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Erik