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Game.Events.AddHealthProblemSystem

Assembly: Game
Namespace: Game.Events

Type: class

Base: GameSystemBase

Summary:
AddHealthProblemSystem listens for event components that indicate citizens should receive health problems (AddHealthProblem), and also responds to building-related events such as Ignite and Destroy. It schedules two primary burst jobs: - FindCitizensInBuildingJob: scans citizens inside a building (for ignite/destroy) and enqueues AddHealthProblem requests for matching citizens. - AddHealthProblemJob: collects AddHealthProblem requests (from entities and the queue), merges multiple problems per citizen, applies or updates HealthProblem components, stops transport/pathing for citizens who require transport, removes/updates notification icons, adds event journal entries, and enqueues TriggerAction entries for further game logic (sick/injured/trapped/in danger).

The system coordinates with: - IconCommandSystem for notifications, - TriggerSystem for triggers, - CityStatisticsSystem for statistics events, - ModificationBarrier4 for safe structural changes.

It uses ECS queries for citizens and healthcare settings and performs work across jobs and main thread command buffers to apply component changes.

Fields

  • private IconCommandSystem m_IconCommandSystem
    This is a reference to the IconCommandSystem used to add/remove notification icons (e.g., ambulance notifications) when health problems require transport or when they clear.

  • private ModificationBarrier4 m_ModificationBarrier
    Barrier system used to create an EntityCommandBuffer for making structural changes (adding HealthProblem components, creating journal entries, etc.) safely from jobs.

  • private EntityQuery m_AddHealthProblemQuery
    Query that finds event entities relevant to adding health problems. It targets Game.Common.Event entities that also have AddHealthProblem, Ignite or Destroy components.

  • private EntityQuery m_HealthcareSettingsQuery
    Query that reads HealthcareParameterData (game settings for healthcare) used to determine death probabilities (e.g., building destroy death rate).

  • private EntityQuery m_CitizenQuery
    Query for Citizen entities with CurrentBuilding (and excluding Deleted) used by the FindCitizensInBuildingJob to iterate citizens.

  • private EntityArchetype m_JournalDataArchetype
    Archetype used to create AddEventJournalData entities when a casualty-related health problem should be logged in the event journal.

  • private TriggerSystem m_TriggerSystem
    Reference to TriggerSystem used to create and enqueue TriggerAction entries (e.g., CitizenGotSick, CitizenGotInjured).

  • private CityStatisticsSystem m_CityStatisticsSystem
    Reference to statistics system used to enqueue statistics events when deaths occur.

  • private TypeHandle __TypeHandle
    Internal struct holding component/lookup handles used to access component data in jobs and to assign handles during system initialization.

Properties

  • None declared on this system.
    This system relies on internal fields and job structs rather than public properties.

Constructors

  • public AddHealthProblemSystem()
    Default constructor. The system's important initialization is done in OnCreate (queries, barriers and child system lookups). The constructor itself is empty/preserved.

Methods

  • protected override void OnCreate() : System.Void
    Initializes queries, gets or creates dependent systems (ModificationBarrier4, IconCommandSystem, TriggerSystem, CityStatisticsSystem), creates m_JournalDataArchetype, and registers required queries for update. This sets up the system so it will run only when relevant event/query data is present.

  • protected override void OnUpdate() : System.Void
    Main update method. Steps performed:

  • Collects event chunks (ignite/destroy/AddHealthProblem).
  • For each Ignite/Destroy that targets a Building, it schedules FindCitizensInBuildingJob to scan citizens whose CurrentBuilding matches and enqueue AddHealthProblem entries (also handling death probability on Destroy).
  • Constructs and schedules AddHealthProblemJob that:
    • Aggregates AddHealthProblem requests from both existing components and the parallel queue.
    • Merges multiple requests per citizen, respecting flags (Dead, RequireTransport, etc.).
    • Updates or adds HealthProblem components, stops transport/pathing where necessary, manipulates icons, writes journal entries, and enqueues TriggerAction events for other systems.

  • Registers and wires job dependencies with ModificationBarrier4, IconCommandSystem, TriggerSystem, and CityStatisticsSystem.

  • protected override void OnCreateForCompiler() : System.Void
    Internal helper used by generated/compiled code to assign queries and TypeHandle component handles. Calls __AssignQueries and assigns component/lookup handles.

  • private void __AssignQueries(ref SystemState state) : System.Void
    Internal method (used during compiler-time setup) prepared for assigning or validating queries. This implementation in the generated code is minimal but required for the compiled system boilerplate.

Notes about nested types: - FindCitizensInBuildingJob (IJobChunk, burst-compiled): iterates citizen archetype chunks, enqueues AddHealthProblem entries for citizens in a specified building and can perform death checks that enqueue statistics/trigger actions. - AddHealthProblemJob (IJob, burst-compiled): merges and applies health problems, manipulates path/transport state for affected citizens, updates icons, creates journal entries and trigger actions. - TypeHandle: holds component type handles and buffer/component lookups passed into jobs.

Usage Example

// Example: Raise an AddHealthProblem request for a citizen entity so AddHealthProblemSystem will process it.
// EntityManager em = ... (get from World or SystemBase)
// Entity eventEntity = em.CreateEntity();
// em.AddComponentData(eventEntity, new Game.Common.Event { /* fill event data if required */ });
// em.AddComponentData(eventEntity, new AddHealthProblem {
//     m_Event = eventEntity,
//     m_Target = targetCitizenEntity,
//     m_Flags = HealthProblemFlags.Sick
// });
// // After this, the AddHealthProblemSystem will pick up the event on its next update and apply a HealthProblem to the target citizen.