Retail CPhysicsObj::FindObjCollisions (0x0050f050) only instant-skips when
BOTH ETHEREAL_PS (0x4) AND IGNORE_COLLISIONS_PS (0x10) are set (pc:276782).
ETHEREAL-alone sets sphere_path.obstruction_ethereal=1 (pc:276806) and
continues to the shape dispatch. BSPTREE::find_collisions (0x0053a496) routes
Path 1 (sphere_intersects_solid) when the flag is set (pc:323742): the open
door has no solid leaf at the doorway, so the test returns OK → player passes
through. CEnvCell::find_env_collisions (0x0052c144) clears the flag first so
ENV walls are never weakened (pc:309580, "D5 clear").
Changes:
- CollisionExemption.ShouldSkip: require BOTH bits for Gate-1 early-out
(previously ETHEREAL alone returned true — the AD-7 shim). Divergence
register row AD-7 deleted.
- SpherePath: add ObstructionEthereal field (mirrors retail
SPHEREPATH.obstruction_ethereal).
- FindObjCollisionsInternal loop: set sp.ObstructionEthereal=(target&0x4)!=0
before shape dispatch; clear it after (per-object clear pc:276989).
Also clear at the null-BSP continue site to keep flag clean.
- FindEnvCollisions: clear sp.ObstructionEthereal=false at top (D5 clear
pc:309580) — ENV cell walls are always solid.
- BSPQuery.FindCollisions Path 1: change `obj.Ethereal` (ObjectInfo.Ethereal,
always false — dead code) to `path.ObstructionEthereal`. Gate now correctly
mirrors retail pc:323742: PLACEMENT_INSERT || obstruction_ethereal.
Consume site change (BSPQuery.cs before/after):
BEFORE: if (path.InsertType == InsertType.Placement || obj.Ethereal)
AFTER: if (path.InsertType == InsertType.Placement || path.ObstructionEthereal)
Mirrors retail pc:323742 exactly. obj.Ethereal was dead code (ObjectInfo.Ethereal
is never set true anywhere); the correct flag is SpherePath.ObstructionEthereal.
Tests: 1580 pass / 0 fail / 2 skip (was 1576/0/2 + 4 new in ObstructionEtherealTests.
CellarUp, CornerFlood, DoorCollision, HouseExitWalk all green — no wall regressions.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
B.4b visual test confirmed the L.2g slice 1 handoff's open question:
ACE's Door.Open() broadcasts state=0x0001000C (HasPhysicsBSP |
Ethereal | ReportCollisions), NOT the state=0x14+ that retail servers
send (Ethereal | IgnoreCollisions). The L.2g pipeline correctly
mutates ShadowObjectRegistry with the new state, but
CollisionExemption.ShouldSkip required both bits and the door stayed
solid.
Retail (acclient_2013_pseudo_c.txt:276782) wraps FindObjCollisions in
`if NOT (state & ETHEREAL && state & IGNORE_COLLISIONS)`. ETHEREAL
alone takes a different retail path at line 276795 that sets
sphere_path.obstruction_ethereal = 1 and lets downstream movement
allow passage despite the contact. We haven't ported that downstream
path yet.
Pragmatic shortcut: widen the early-out to ETHEREAL alone so doors
become passable when ACE flips the bit. Retail-server broadcasts
still hit the same branch correctly (both bits set implies ETHEREAL).
Compatible with both server styles.
Renames test EtherealOnly_NotSkipped -> EtherealOnly_Skipped and
flips its assertion. 13 CollisionExemption tests pass; full suite
1046 pass / 8 pre-existing baseline fail (unchanged).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
The retail-faithful exemption block at the top of
CPhysicsObj::FindObjCollisions
(acclient_2013_pseudo_c.txt:276782-276839,276971), ported line-for-
line as a small static helper.
Behaviour now matches retail:
- Two non-PK players walk through each other.
- Two PK players collide.
- Two PKLite players collide.
- Mismatched PK status (PK vs non-PK, PK vs PKLite) — exempt.
- Impenetrable target ("Free" PK status) — always collides.
- Player vs creature/NPC — always collides (this is what closes the
user-facing complaint that walking into a Holtburg vendor was
walking through them).
- Mover with IGNORE_CREATURES — walks through creature targets.
- Viewer (camera ray) — walks through creatures.
- Target with ETHEREAL+IGNORE_COLLISIONS — universally exempt.
CollisionExemption.ShouldSkip(targetState, targetFlags, moverState)
- new file src/AcDream.Core/Physics/CollisionExemption.cs.
- 13-test matrix covering every documented case
(CollisionExemptionTests.cs).
- Static + pure → cheap to call from the hot path.
Wiring:
- TransitionTypes.FindObjCollisions: after broadphase distance
reject, call ShouldSkip on the obj and ObjectInfo.State; on true,
`continue`. Static landblock entries (State=0, Flags=None) fall
through cheaply — no behavior change for static collision.
- PhysicsEngine.ResolveWithTransition: new optional moverFlags
parameter (default None for back-compat). PlayerMovementController
passes ObjectInfoState.IsPlayer; remote dead-reckoning leaves it
None (matches non-player movers, no PvP exemption applies).
- PK/PKLite/Impenetrable bits for the LOCAL player are not yet
sourced from PlayerDescription's PlayerKillerStatus property —
that's a follow-up. Default "non-PK player" matches ACE's
character-creation default and the user's +Acdream test
character.
Cross-checked against ACE PhysicsObj.cs:381-405 (line-for-line C# port
of the same retail block). Only intentional divergence: ACE adds
state.HasFlag(IsImpenetrable) (mover-impenetrable) to the collide list;
retail's pseudo-C only checks the target — acdream follows retail.
dotnet build green, dotnet test 1467 passing (+13 new). Live test:
+Acdream walking into Holtburg vendors now stops at their cylinder;
walking through small plants still passes (Commit B's phantom skip).
Closes the live-entity collision arc: A (plumbing) + B (registration)
+ C (exemption).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
