BP_NarrativeTriggerVolume — Actor (with BoxComponent as root)

Blueprint Spec — UE 5.5–5.7

Parent Class

Actor (with BoxComponent as root)

Dependencies

Purpose

A level-placed trigger volume that detects player overlap and fires narrative actions. Supports one-shot / reusable / conditional modes, with optional prerequisite flags and cooldown timers. The primary way for level designers to trigger narrative events without blueprint logic.

Responsibilities

Detect player BeginOverlap / EndOverlap
Check prerequisite flags (required and exclusive)
Execute configured actions on trigger (fire-and-forget)
Support trigger types: Once, Reusable, Conditional, TimedAutoReset
Broadcast onset / offset variants if configured
Prevent re-trigger during cooldown

Does NOT Handle

Playing dialogue or cutscenes directly (calls the relevant system)
Setting flags on the NarrativeState (that is what the actions do)
UI display (that is UI layer)

Variables

Name	Type	Description
`TriggerTag`	GameplayTag	Unique identifier for this trigger
`TriggerType`	ETriggerType	How the trigger behaves
`TriggerActions`	Array of FTriggerActionEntry	Actions to fire when triggered
`bAlsoFireOnExit`	Bool	Fire separate actions when player exits
`ExitActions`	Array of FTriggerActionEntry	Actions fired on exit (if enabled)
`RequiredFlags`	Array of GameplayTag	All must be set to enable
`ExclusiveFlags`	Array of GameplayTag	If any are set, trigger is disabled
`CooldownSeconds`	Float	Time before reusable triggers can re-fire
`bHasTriggered`	Bool	Has fired at least once
`bIsEnabled`	Bool	Can be toggled on/off by external systems
`LastTriggerTime`	Float	World time of last trigger
`CollisionBox`	BoxComponent	The overlap volume
`TriggerDisplayName`	FText	Editor-friendly name
`bDebugMode`	Bool	Print trigger events to screen

Enums

Enum	Values	Description
`ETriggerType`	Once, Reusable, ConditionalOnce, ConditionalReusable, TimedAutoReset	Once: fires first time only. Reusable: fires every time with cooldown. Conditional*: checks flags each time. TimedAutoReset: resets after cooldown.
`ENarrativeActionType`	SetFlag, ClearFlag, PlayDialogue, StartCutscene, BeginScenario, UnlockLore, UpdateObjective, PlaySound, ExecuteConsoleCommand, ToggleActorEnabled, CustomEvent	Types of actions a trigger can perform

Structs

Struct	Fields	Description
`FTriggerActionEntry`	ActionType: ENarrativeActionType, TargetTag: GameplayTag, FloatParam: Float (delay), StringParam: FString (for console commands), bBlocking: Bool (wait for completion), DelayBeforeFire: Float	One action entry in the trigger action list
`FTriggerConditionState`	bMetRequirements: Bool, bBlockedByExclusive: Bool, bOnCooldown: Bool, bAlreadyTriggered: Bool	Debug state of trigger conditions

Functions / Events

Name	Inputs	Outputs	Description
`OnPlayerEntered`	OverlappedComp: PrimitiveComponent, OtherActor: Actor	—	BeginOverlap event
`OnPlayerExited`	OverlappedComp: PrimitiveComponent, OtherActor: Actor	—	EndOverlap event (if bAlsoFireOnExit)
`EvaluateTriggerConditions`	—	Bool (can fire)	Check all conditions
`FireTrigger`	—	—	Execute all trigger actions
`ExecuteActionEntry`	Entry: FTriggerActionEntry	—	Perform one action
`ResetTrigger`	—	—	Reset bHasTriggered (for TimedAutoReset)
`SetTriggerEnabled`	bEnabled: Bool	—	External toggle
`GetTriggerState`	—	FTriggerConditionState	Debug info
`ManualTrigger`	—	—	Force trigger from external BP
`PreviewActions`	—	—	Editor preview of what this trigger does

Event Dispatchers

Name	Parameters	Fired When
`OnTriggerPrepared`	TriggerTag: GameplayTag	Conditions met, about to fire
`OnTriggerFired`	TriggerTag: GameplayTag, ActionCount: Integer	All actions executed
`OnTriggerBlocked`	TriggerTag: GameplayTag, Reason: FName	Conditions not met
`OnTriggerCooldown`	TriggerTag: GameplayTag, RemainingCooldown: Float	Cooldown active
`OnTriggerReset`	TriggerTag: GameplayTag	Trigger reset for reuse

Blueprint Flow

[OnPlayerEntered]
  └─► If !bIsEnabled → return
  └─► If EvaluateTriggerConditions == false → broadcast OnTriggerBlocked → return
  └─► FireTrigger

[EvaluateTriggerConditions]
  └─► If TriggerType == Once && bHasTriggered → return false (already fired)
  └─► If TriggerType == ConditionalOnce && bHasTriggered → return false
  └─► If TriggerType == TimedAutoReset && !bHasTriggered → skip (but can fire if reset)
  └─► Check RequiredFlags: all must be set in BPC_NarrativeStateSystem
  └─► Check ExclusiveFlags: none must be set
  └─► If TriggerType == Reusable || ConditionalReusable:
      └─► Check LastTriggerTime + CooldownSeconds < CurrentTime
      └─► If on cooldown → broadcast OnTriggerCooldown → return false
  └─► Return true (all conditions pass)

[FireTrigger]
  └─► Broadcast OnTriggerPrepared
  └─► Set bHasTriggered = true
  └─► Set LastTriggerTime = CurrentTime
  └─► For each FTriggerActionEntry in TriggerActions (in order):
      └─► If entry.DelayBeforeFire > 0 → delay via timer
      └─► ExecuteActionEntry(Entry)
  └─► If bAlsoFireOnExit → bind OnPlayerExited to execute ExitActions
  └─► Broadcast OnTriggerFired
  └─► If TriggerType == TimedAutoReset → start timer for ResetTrigger after CooldownSeconds

[ExecuteActionEntry: Entry]
  └─► Switch on Entry.ActionType:
      SetFlag → BPC_NarrativeStateSystem.SetFlag(Entry.TargetTag)
      ClearFlag → BPC_NarrativeStateSystem.ClearFlag(Entry.TargetTag)
      PlayDialogue → Get BPC_DialoguePlaybackSystem → PlaySequence(Entry.TargetTag)
      StartCutscene → Get BPC_CutsceneBridge → PlayCutscene(Entry.TargetTag as DA_CutsceneData)
      BeginScenario → Get BPC_TrialScenarioSystem → BeginScenario(Entry.TargetTag as DA_ScenarioData)
      UnlockLore → Get BPC_LoreUnlockSystem → UnlockLoreByTag(Entry.TargetTag)
      UpdateObjective → Get BPC_ObjectiveSystem → AddOrUpdateObjective(...)
      PlaySound → Play sound at volume location
      ExecuteConsoleCommand → Exec(Entry.StringParam)
      ToggleActorEnabled → Find actor by tag, toggle set actor hidden / disable collision
      CustomEvent → Dispatch custom gameplay event tag (listeners in level blueprint)

Communications With

Target System	Method	Why
`BPC_NarrativeStateSystem`	Direct	Check/set flags for conditions and actions
`BPC_DialoguePlaybackSystem`	Direct	Trigger dialogue sequences
`BPC_CutsceneBridge`	Direct	Start cutscenes
`BPC_TrialScenarioSystem`	Direct	Begin trial scenarios
`BPC_LoreUnlockSystem`	Direct	Unlock lore
`BPC_ObjectiveSystem`	Direct	Update objectives
Level Blueprint	Dispatcher (CustomEvent)	Layer for designer-specific logic

Placement in Level

Drag into level from Content Browser
Scale BoxComponent to desired trigger area
Configure TriggerActions array in Details panel
Tag with TriggerTag for save/load identification
Optional: set PrerequisiteFlags to gate the trigger

Reuse Notes

This is the primary level-design tool for narrative gating. Designers place volumes, configure action lists, and set prerequisite flags — no blueprint editing required. Supports all narrative action types. The CustomEvent action type allows designers to bind custom level blueprint logic when no predefined action fits.

Renamed from 47_BPC_NarrativeTriggerVolume to BP_NarrativeTriggerVolume per Master naming convention.

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