feat: MobSync

[Liparakis]

Meaningful Changes

Animation & Visual Hits (DamageAnimationEffect.cs)

• Changed:

  • Caches delegate subscriptions for visual damage effects (WillDamageEnemyOptionsDelegate and DamagedEnemyHealthManagerDelegate) to avoid repeated delegate allocations on hit processing paths.
  • Subscribes to UnityEngine.SceneManagement.SceneManager.activeSceneChanged to clear the static RemoteVisualHitHpBefore tracking dictionary between scenes.
  • Reworks FixDamageEnemies so remote attack replicas can trigger visual hit feedback while disabling lethal triggers, non-lethal side effects, and death events. The enemy HP is recorded before the remote hit and restored after the hit event completes.

• Why it matters:

  • Reduces allocation pressure during repeated hit processing.
  • Avoids stale static hit-state leaking across scene transitions.
  • Allows remote player attacks to produce visible hit reactions without applying unauthorized local damage, double damage, or client-side kills.

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Pause & Input Management (PauseManager.cs)

• Changed:

  • Replaces previously commented-out placeholders with active MonoMod.RuntimeDetour.Hook instances targeting UIManager.TogglePauseGame, HeroController.Pause, TransitionPoint.OnTriggerEnter2D, and HeroController.DieFromHazard.
  • Forces Time.timeScale back to 1f while multiplayer pause handling is active so world simulation can continue for other players.
  • Disables input and clears selected button state during forced unpause flows.
  • Forces immediate unpausing on death, hazard death, and scene transitions to reduce the risk of pause-menu softlocks.

• Why it matters:

  • Prevents one player’s pause state from freezing shared world simulation.
  • Reduces softlock risk when pause state overlaps with death, hazard respawn, or scene transition flows.
  • Keeps multiplayer world state moving even when local UI pause behavior is active.

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Player-Player Collisions (PlayerManager.cs)

• Changed:

  • Disables collisions between the local player and remote players inside CreateNewPlayerContainer by calling Physics2D.IgnoreCollision across local and remote colliders.
  • Registers and unregisters remote player root objects through PlayerTargetRegistry.

• Why it matters:

  • Prevents remote player replicas from physically pushing, blocking, or displacing the local player.
  • Centralizes remote player target/collider tracking for systems that need to query valid player targets.

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FSM Performance & Garbage Collection (Entity.cs, EntityFsmActions.cs)

• Changed:

  • Replaces generic delegates and closure-heavy FSM synchronization helpers, such as CondAddData and CondUpdateVars, with direct type-specific loops for floats, ints, bools, strings, Vector2, and Vector3.
  • Replaces PlayMaker/Animator hook setup with explicit MonoMod.RuntimeDetour.Hook fields.
  • Replaces Dictionary<FsmStateAction, Queue<object>> RandomActionValues with ConditionalWeakTable<FsmStateAction, Queue<object>>.

• Why it matters:

  • Reduces frame-by-frame GC allocations in hot FSM synchronization paths.
  • Makes hook lifetime easier to reason about by storing explicit hook references.
  • Allows randomized action data associated with FsmStateAction instances to be collected once the action is no longer strongly referenced elsewhere.

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Registry Generalization & Silksong Port (EntityRegistry.cs, EntityType.cs)

• Changed:

  • Replaces hardcoded type-check structures with generalized metadata-driven registry matching using fields such as FsmNames and parent_name.
  • Uses a deserialized HashSet<string> cache (_fsmNameSet) for faster FSM name lookups in registry entry matching.
  • Ports the entity type enum and registry lookup structure from the Hollow Knight version toward the Silksong Entity V1 system.

• Why it matters:

  • Reduces one-off hardcoded entity handling.
  • Makes new entity support easier to add through registry metadata instead of source-level conditionals.
  • Improves lookup cost for repeated FSM-name matching.

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Component Updates & Centralization (EntityComponent.cs and Components)

• Changed:

  • Replaces decentralized component update subscriptions through MonoBehaviourUtil.Instance.OnUpdateEvent with a centralized update path where Entity.OnUpdate() drives EntityComponent.OnUpdate().
  • Passes sceneHostEpoch into InitializeHost and InitializeClient during component setup.

• Why it matters:

  • Reduces the number of individual update-event subscriptions.
  • Makes component update order and lifecycle easier to reason about from the owning entity.
  • Propagates scene-host epoch context into component initialization.

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Entity Update Lifetime & Buffer Lifecycles (EntityManager.cs, ClientManager.cs)

• Changed:

  • Renames _receivedUpdates to _pendingUpdates.
  • Implements DrainPendingUpdates() and returns processed updates to the object pool with ObjectPool<EntityUpdate>.Return.
  • Retains ownership of queued updates until they are successfully applied or discarded during entity destruction.
  • Hooks FindGameObject.OnEnter so FSM queries can locate entities that the system has deactivated.
  • Replaces full scene traversal inside FindEntitiesInScene with targeted component candidate gathering.

• Why it matters:

  • Fixes a critical lifetime issue where buffered network updates could be returned to the pool before the entity finished consuming them.
  • Reduces the risk of pooled update data being overwritten while still logically active.
  • Helps host-transfer and FSM restoration paths find inactive controller assets.
  • Reduces expensive full-scene traversal during entity discovery.

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Health Synchronization (HealthManagerComponent.cs)

• Changed:

  • Implements epoch/update-id tracking for health synchronization using _currentHealthEpoch and _nextHealthUpdateId.
  • Tracks health update sequencing per sender.
  • Pools EntityNetworkData objects used for HP and invincibility updates.
  • Delays client-side HP increases by 0.4 seconds to verify whether the increase is backed by host authority, rolling back unauthorized local increases when needed.

• Why it matters:

  • Improves protection against duplicate, stale, and out-of-order health packets.
  • Reduces allocation pressure during combat-heavy synchronization.
  • Reduces the risk of unauthorized client-side healing or stale HP restoration.

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Packet Serialization (IPacket.cs, Packet.cs, UpdatePacket.cs, EntityUpdate.cs, PlayerUpdate.cs)

• Changed:

  • Adds ReadPacketView(length) to return a sub-packet view over an existing packet buffer without copying the byte array.
  • Replaces Enum.GetNames(typeof(T)) with EnumCache<T>.Count for enum-size lookup.
  • Reuses the existing AckField array in UpdatePacket when it already has the correct size.

• Why it matters:

  • Reduces allocation pressure in network serialization/deserialization paths.
  • Avoids repeated enum reflection in packet parsing.
  • Avoids allocating a new acknowledgement array for every compatible received update packet.

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Deferred / New Files

These files are intentionally listed separately because they are new or mostly self-contained. They should be reviewed after existing behavior changes.

• SSMP/Game/Client/GamePatcher.EnemyTargeting.cs

  • New enemy target allocation and redirection logic.
  • Uses distance hysteresis and approved target selection for enemy FSM actions.
  • Review after existing synchronization, lifecycle, and hook changes.

• SSMP/Game/Client/GamePatcher.PlayerDetection.cs

  • New player detection/range detour logic.
  • Uses frame-cached bounds and detection helpers.
  • Review after existing synchronization, lifecycle, and hook changes.

• SSMP/Game/Client/PlayerTargetRegistry.cs

  • New static tracking helper for remote player instances and collider components.
  • Review for lifecycle cleanup, scene-change behavior, and disconnect handling.

• SSMP/Util/EnumCache.cs

  • New generic enum-size cache used to avoid repeated enum reflection.
  • Low complexity, but verify it behaves correctly for all enum types used in packet serialization.