test(physics): pin issue 270 animation fixes

src/AcDream.App/Net/LiveSessionRuntimeFactory.cs

@@ -98,6 +98,7 @@ internal sealed class LiveSessionRuntimeFactory
     private readonly LiveSessionWorldRuntime _world;
     private readonly LiveSessionCommandSurface _commands;
     private readonly Action<string> _log;
+    private readonly StaminaExhaustionEdgeTracker _staminaExhaustion = new();
 
     public LiveSessionRuntimeFactory(
         LiveSessionPlayerRuntime player,
@@ -189,6 +190,7 @@ internal sealed class LiveSessionRuntimeFactory
 
     private void ResetPlayerPresentation()
     {
+        _staminaExhaustion.Reset();
         _interaction.PlayerMode.ResetSession();
         _world.SpawnClaims.Reset();
     }
@@ -289,13 +291,6 @@ internal sealed class LiveSessionRuntimeFactory
             OnMovementStatsUpdated: () => ApplyMovementStats("stats"));
     }
 
-    /// <summary>
-    /// Tracks the previous "stamina exhausted" state so
-    /// <see cref="ApplyMovementStats"/> can fire retail's exhaustion
-    /// notification on the EDGE only. Null = no stamina reading applied yet.
-    /// </summary>
-    private bool? _lastStaminaExhausted;
-
     /// <summary>
     /// Re-applies the current <see cref="RuntimeMovementSkillState"/>
     /// snapshot (skills/burden/stamina) to the live player controller.
@@ -328,14 +323,8 @@ internal sealed class LiveSessionRuntimeFactory
         }
 
         RuntimeMovementSkillSnapshot snapshot = _domain.Character.MovementSkills.Snapshot;
-        bool exhausted = snapshot.CurrentStamina == 0;
-        if (_lastStaminaExhausted != exhausted)
-        {
-            bool isEdge = _lastStaminaExhausted is not null;
-            _lastStaminaExhausted = exhausted;
-            if (isEdge)
-                controller!.Motion.ReportExhaustion();
-        }
+        if (_staminaExhaustion.Observe(snapshot.CurrentStamina))
+            controller!.Motion.ReportExhaustion();
 
         _log(
             $"player: applied server movement {reason} "

src/AcDream.App/Net/StaminaExhaustionEdgeTracker.cs

@@ -0,0 +1,32 @@
+namespace AcDream.App.Net;
+
+/// <summary>
+/// Tracks retail's stamina-exhaustion notification edge for one live-session
+/// generation.
+/// </summary>
+internal sealed class StaminaExhaustionEdgeTracker
+{
+    private bool? _wasExhausted;
+
+    /// <summary>
+    /// Observes the current stamina value and returns <see langword="true"/>
+    /// only when a previously initialized state changes between exhausted and
+    /// non-exhausted.
+    /// </summary>
+    public bool Observe(int currentStamina)
+    {
+        bool exhausted = currentStamina == 0;
+        if (_wasExhausted == exhausted)
+            return false;
+
+        bool isEdge = _wasExhausted.HasValue;
+        _wasExhausted = exhausted;
+        return isEdge;
+    }
+
+    /// <summary>
+    /// Forgets the retiring character/session sample. The first sample in the
+    /// next generation establishes a baseline and must not synthesize an edge.
+    /// </summary>
+    public void Reset() => _wasExhausted = null;
+}

src/AcDream.App/Physics/LiveEntityNetworkUpdateController.cs

@@ -168,9 +168,6 @@ internal sealed class LiveEntityNetworkUpdateController
         System.Numerics.Vector3 worldPos,
         uint cellId)
     {
-        if (cellId == 0)
-            return;
-
         var (radius, height) = _motionRuntime.GetSetupCylinder(serverGuid, entity);
         if (radius < 0.05f)
         {
@@ -193,33 +190,20 @@ internal sealed class LiveEntityNetworkUpdateController
         // retail's first frame would (position snapped onto the floor,
         // contact plane + CONTACT/ON_WALKABLE committed below). A sweep that
         // finds no floor (true airborne spawn) leaves the body airborne.
-        AcDream.Core.Physics.ResolveResult settle = _physicsEngine.ResolveWithTransition(
-            worldPos,
-            worldPos + new System.Numerics.Vector3(0f, 0f, -0.5f),
-            cellId,
-            sphereRadius: radius,
-            sphereHeight: height,
-            stepUpHeight: 0.4f,
-            stepDownHeight: 0.4f,
-            isOnGround: false,
-            body: remote.Body,
-            moverFlags: moverFlags,
-            movingEntityId: entity.Id);
-        if (!settle.Ok || !settle.InContact)
-            return; // no floor within reach — stays airborne like retail's fall
-
-        remote.Body.Position = settle.Position;
-
-        AcDream.Core.Physics.PhysicsObjUpdate.CommitSetPositionTransition(
+        if (!RemoteSpawnPlacementSettler.TrySettle(
+            _physicsEngine,
             remote.Body,
-            settle.InContact,
-            settle.OnWalkable,
-            settle.CollisionNormalValid,
-            settle.CollisionNormal,
-            previousContact: false,
-            previousOnWalkable: false,
+            worldPos,
+            cellId,
+            radius,
+            height,
+            moverFlags,
+            entity.Id,
             remote.Movement.HitGround,
-            remote.Motion.LeaveGround);
+            remote.Motion.LeaveGround))
+        {
+            return; // no floor within reach — stays airborne like retail's fall
+        }
         remote.Airborne = !remote.Body.OnWalkable;
     }
 

src/AcDream.App/Physics/RemoteSpawnPlacementSettler.cs

@@ -0,0 +1,62 @@
+using System.Numerics;
+using AcDream.Core.Physics;
+
+namespace AcDream.App.Physics;
+
+/// <summary>
+/// Performs the compressed first-gravity-frame settle used to establish
+/// retail Contact/OnWalkable state for a newly materialized remote body.
+/// </summary>
+internal static class RemoteSpawnPlacementSettler
+{
+    internal const float SettleDistance = 0.5f;
+
+    public static bool TrySettle(
+        PhysicsEngine physicsEngine,
+        PhysicsBody body,
+        Vector3 worldPosition,
+        uint cellId,
+        float sphereRadius,
+        float sphereHeight,
+        ObjectInfoState moverFlags,
+        uint movingEntityId,
+        Action hitGround,
+        Action leaveGround)
+    {
+        ArgumentNullException.ThrowIfNull(physicsEngine);
+        ArgumentNullException.ThrowIfNull(body);
+        ArgumentNullException.ThrowIfNull(hitGround);
+        ArgumentNullException.ThrowIfNull(leaveGround);
+
+        if (cellId == 0)
+            return false;
+
+        ResolveResult settle = physicsEngine.ResolveWithTransition(
+            worldPosition,
+            worldPosition - new Vector3(0f, 0f, SettleDistance),
+            cellId,
+            sphereRadius,
+            sphereHeight,
+            stepUpHeight: 0.4f,
+            stepDownHeight: 0.4f,
+            isOnGround: false,
+            body,
+            moverFlags,
+            movingEntityId);
+        if (!settle.Ok || !settle.InContact)
+            return false;
+
+        body.Position = settle.Position;
+        PhysicsObjUpdate.CommitSetPositionTransition(
+            body,
+            settle.InContact,
+            settle.OnWalkable,
+            settle.CollisionNormalValid,
+            settle.CollisionNormal,
+            previousContact: false,
+            previousOnWalkable: false,
+            hitGround,
+            leaveGround);
+        return true;
+    }
+}