NPCPreTickSystem

Package: com.hypixel.hytale.server.npc.systems

public class NPCPreTickSystem extends SteppableTickingSystem

Runs at the beginning of the NPC tick pipeline. Stores the tick-start position (used later by ComputeVelocitySystem), and manages the NPC despawn lifecycle including despawn timers, despawn animations, and despawn checks.

Execution Order

Dependency	Direction
DeathSystems.CorpseRemoval	BEFORE

Constructor

public NPCPreTickSystem(@Nonnull ComponentType<EntityStore, NPCEntity> npcComponentType)

Query

Matches entities with NPCEntity and TransformComponent.

Tick Logic

@Override
public void steppedTick(
    float dt,
    int index,
    @Nonnull ArchetypeChunk<EntityStore> archetypeChunk,
    @Nonnull Store<EntityStore> store,
    @Nonnull CommandBuffer<EntityStore> commandBuffer
)

1. Stores the current position as the tick-start position via npcComponent.storeTickStartPosition(position).
2. Despawn animation phase: If playing a despawn animation, ticks the animation timer. On expiry, removes the entity.
3. Despawn timer phase: If despawning, ticks the despawn timer. On expiry, checks for a “Despawn” animation. If present, transitions to the animation phase. Otherwise, removes the entity immediately.
4. Despawn check phase: Every 30 seconds (DEFAULT_DESPAWN_CHECK_DELAY), queries SpawningPlugin.shouldNPCDespawn(). If the NPC should despawn and is not in a busy state, initiates the despawn timer.

Constants

Constant	Value	Description
DEFAULT_DESPAWN_CHECK_DELAY	30.0F	Seconds between despawn eligibility checks.

Parallelism

Returns EntityTickingSystem.maybeUseParallel(archetypeChunkSize, taskCount).

Related Types

• ComputeVelocitySystem — uses the tick-start position stored by this system
• SpawnReferenceSystems — spawn marker/beacon despawn logic