NiagaraDynamicParametersListenerComponent Documentation

Core Concept

The fundamental principle of this system is simple: The component maintains a set of active gameplay tags accessible via GetActiveGameplayTags() that returns the ActiveGameplayTags property, and these tags determine which parameter overrides are applied to registered Niagara effects.

Everything else is optional utility functionality. You can implement your own custom logic and simply call UpdateGameplayTags(NewTags) to replace the active tags whenever your game state changes. The component will automatically apply the appropriate parameter overrides based on the new tags.

Essential Methods

GetActiveGameplayTags() - Returns the current active tags that drive parameter overrides
UpdateGameplayTags(NewTags) - Replaces all active tags with your custom set

Optional Utility Methods

All other methods are convenience utilities for the built-in tag management and effect registration system:

AddGameplayTags() / RemoveGameplayTags() - Incremental tag modifications
RegisterNiagaraEffect() / UnregisterNiagaraEffect() - Built-in effect registration system
RefreshAllEffects() / CleanupInactiveEffects() - Maintenance utilities
Query methods and events - Information and debugging support

You can ignore the built-in utilities and create your own system that calls UpdateGameplayTags() based on any custom logic (AI states, player actions, environmental conditions, etc.).

Overview

The UDNAListenerComponent is the core component of the Dynamic Niagara for Animation (DNA) system. It manages gameplay tag-based parameter overrides for Niagara effects, enabling dynamic visual effects that respond to game state changes in real-time.

Component Setup

Adding to an Actor

// C++ - Add to actor constructor
ListenerComponent = CreateDefaultSubobject<UDNAListenerComponent>(TEXT("DNAListener"));

// Blueprint - Add Component in the Components panel
Add Component -> DNA - Listener Component

Basic Configuration

Property	Type	Default	Description
bEnabled	`bool`	`true`	Master enable/disable switch for the entire component
bAutoCleanupInactiveEffects	`bool`	`true`	Whether to automatically clean up inactive effects using a timer
CleanupInterval	`float`	`1.0`	How often to check for and clean up inactive effects (seconds)
bLogParameterChanges	`bool`	`false`	Whether to log parameter changes for debugging

Blueprint API Reference

Network Authority

HasNetworkAuthority

HasNetworkAuthority() -> bool

Category: Niagara Dynamic Parameters|Network
Type: BlueprintPure

Checks if this component has network authority to modify gameplay tags.

Returns:

bool: True if component has authority (server in multiplayer, always true in standalone)

Usage Example:

if (DNAListener.HasNetworkAuthority())
{
    // Safe to modify tags
    DNAListener.AddGameplayTags(NewTags);
}

Gameplay Tag Management

AddGameplayTags

AddGameplayTags(TagsToAdd: GameplayTagContainer)

Category: Niagara Dynamic Parameters|Gameplay Tags
Type: BlueprintCallable, BlueprintNativeEvent

Adds new gameplay tags to the active tag container. Triggers parameter updates on all registered effects.

Parameters:

TagsToAdd (FGameplayTagContainer): Container of gameplay tags to add to the active set

Authority: Requires network authority. Will log warning and return early if called without authority.

Usage Example:

// Add combat-related tags
TagContainer CombatTags;
CombatTags.AddTag("Combat.Active");
CombatTags.AddTag("Combat.Melee");
DNAListener.AddGameplayTags(CombatTags);

UpdateGameplayTags

UpdateGameplayTags(NewTags: GameplayTagContainer)

Category: Niagara Dynamic Parameters|Gameplay Tags
Type: BlueprintCallable

Replaces the entire active gameplay tag container with new tags.

Parameters:

NewTags (FGameplayTagContainer): New set of gameplay tags to replace current active tags

Authority: Requires network authority.

Usage Example:

// Switch from combat to stealth mode
TagContainer StealthTags;
StealthTags.AddTag("Stealth.Active");
StealthTags.AddTag("Movement.Crouched");
DNAListener.UpdateGameplayTags(StealthTags);

RemoveGameplayTags

RemoveGameplayTags(TagsToRemove: GameplayTagContainer, RemovalMode: EGameplayTagRemovalMode)

Category: Niagara Dynamic Parameters|Gameplay Tags
Type: BlueprintCallable, BlueprintNativeEvent

Removes gameplay tags from the active tag container.

Parameters:

TagsToRemove (FGameplayTagContainer): Container of gameplay tags to remove
RemovalMode (EGameplayTagRemovalMode): How to handle tag removal

Removal Modes:

ExactMatch: Remove only exact matching tags
WithDescendants: Remove the tag and all its descendant tags (e.g., "Combat.Melee" removes "Combat.Melee.Sword")

Authority: Requires network authority.

Usage Example:

// Remove all combat-related tags and their children
TagContainer CombatTags;
CombatTags.AddTag("Combat");
DNAListener.RemoveGameplayTags(CombatTags, EGameplayTagRemovalMode::WithDescendants);

GetTagsWithDescendants

GetTagsWithDescendants(Tags: GameplayTagContainer) -> GameplayTagContainer

Category: Niagara Dynamic Parameters|Gameplay Tags
Type: BlueprintCallable, Static

Utility function to get a tag container that includes specified tags and all their descendants.

Parameters:

Tags (FGameplayTagContainer): Input tags to expand with descendants

Returns:

FGameplayTagContainer: Container with original tags plus all descendant tags

Usage Example:

// Get all combat-related tags including children
TagContainer CombatBase;
CombatBase.AddTag("Combat");
GameplayTagContainer AllCombatTags = GetTagsWithDescendants(CombatBase);
// Result might include: Combat, Combat.Melee, Combat.Ranged, Combat.Melee.Sword, etc.

Effect Management

RegisterNiagaraEffect

RegisterNiagaraEffect(NiagaraComponent: NiagaraComponent, Configuration: NiagaraSystemConfiguration, SourceNotifyName: string = "")

Category: Niagara Dynamic Parameters|Effect Management
Type: BlueprintCallable

Registers a Niagara component with this listener to receive dynamic parameter updates.

Parameters:

NiagaraComponent (UNiagaraComponent*): The Niagara component to register
Configuration (FNiagaraSystemConfiguration): System configuration containing parameter override rules
SourceNotifyName (FString): Optional name of the animation notify that spawned this effect (for debugging)

Usage Example:

// Register an effect spawned by an animation notify
NiagaraComponent SpawnedEffect = SpawnNiagaraSystem(...);
DNAListener.RegisterNiagaraEffect(SpawnedEffect, EffectConfiguration, "Attack_Slash_Notify");

UnregisterNiagaraEffect

UnregisterNiagaraEffect(NiagaraComponent: NiagaraComponent)

Category: Niagara Dynamic Parameters|Effect Management
Type: BlueprintCallable

Unregisters a Niagara component from this listener, stopping dynamic parameter updates.

Parameters:

NiagaraComponent (UNiagaraComponent*): The Niagara component to unregister

Usage Example:

// Manually unregister an effect
DNAListener.UnregisterNiagaraEffect(MyNiagaraEffect);

RefreshAllEffects

RefreshAllEffects()

Category: Niagara Dynamic Parameters|Effect Management
Type: BlueprintCallable

Forces a refresh of parameter overrides on all registered Niagara effects. Automatically called when gameplay tags change.

Usage Example:

// Force refresh after manual parameter changes
DNAListener.RefreshAllEffects();

CleanupInactiveEffects

CleanupInactiveEffects()

Category: Niagara Dynamic Parameters|Effect Management
Type: BlueprintCallable

Manually removes inactive effects from the registration list. Automatically done based on cleanup settings.

Usage Example:

// Manual cleanup trigger
DNAListener.CleanupInactiveEffects();

Queries and Getters

GetActiveGameplayTags

GetActiveGameplayTags() -> GameplayTagContainer

Category: Niagara Dynamic Parameters|Queries
Type: BlueprintCallable, BlueprintNativeEvent

Gets the currently active gameplay tags.

Returns:

FGameplayTagContainer: Container with all currently active gameplay tags

Usage Example:

GameplayTagContainer CurrentTags = DNAListener.GetActiveGameplayTags();
if (CurrentTags.HasTag("Combat.Active"))
{
    // Player is in combat
}

GetActiveNiagaraComponents

GetActiveNiagaraComponents() -> Array<NiagaraComponent>

Category: Niagara Dynamic Parameters|Queries
Type: BlueprintPure

Gets all currently registered and active Niagara components.

Returns:

TArray<UNiagaraComponent*>: Array of active Niagara components

Usage Example:

Array<NiagaraComponent> ActiveEffects = DNAListener.GetActiveNiagaraComponents();
PrintString("Active effects count: " + string(ActiveEffects.Length));

GetActiveEffectCount

GetActiveEffectCount() -> int32

Category: Niagara Dynamic Parameters|Queries
Type: BlueprintPure

Gets the number of currently registered effects.

Returns:

int32: Number of effects currently registered with this listener

Usage Example:

int32 EffectCount = DNAListener.GetActiveEffectCount();
if (EffectCount > 10)
{
    // Too many effects, maybe cleanup needed
}

GetActiveEffects

GetActiveEffects() -> Array<ActiveNiagaraEffectInfo>

Category: Debug
Type: BlueprintPure

Gets detailed information about all active effects (primarily for debugging).

Returns:

TArray<FActiveNiagaraEffectInfo>: Array of effect info structures

Usage Example:

Array<ActiveNiagaraEffectInfo> EffectInfos = DNAListener.GetActiveEffects();
ForEach EffectInfo in EffectInfos
{
    PrintString("Effect: " + EffectInfo.SourceNotifyName + " - Spawn Time: " + string(EffectInfo.SpawnTime));
}

Events

OnParametersUpdated

OnParametersUpdated(ActiveTags: GameplayTagContainer, AppliedOverrides: Array<NiagaraParameterOverride>)

Category: Events
Type: BlueprintAssignable (Multicast Delegate)

Event fired whenever parameters are updated on registered effects.

Parameters:

ActiveTags (FGameplayTagContainer): The currently active gameplay tags
AppliedOverrides (TArray<FNiagaraParameterOverride>): Array of parameter overrides that were applied

Usage Example:

// Bind to the event
DNAListener.OnParametersUpdated.AddDynamic(this, HandleParametersUpdated);

// Event handler function
function HandleParametersUpdated(ActiveTags: GameplayTagContainer, AppliedOverrides: Array<NiagaraParameterOverride>)
{
    PrintString("Parameters updated! Active tags: " + ActiveTags.ToString());
    PrintString("Applied " + string(AppliedOverrides.Length) + " overrides");
}

Data Types

EGameplayTagRemovalMode

Enumeration defining how gameplay tags should be removed from the active tag container.

Value	Description
`ExactMatch`	Remove only exact matching tags
`WithDescendants`	Remove the tag and all its descendant tags

FActiveNiagaraEffectInfo

Structure containing information about an active Niagara effect registered with the listener component.

Property	Type	Description
`NiagaraComponent`	`TWeakObjectPtr<UNiagaraComponent>`	Weak reference to the registered Niagara component
`Configuration`	`FNiagaraSystemConfiguration`	Configuration used for this effect including parameter overrides
`SpawnTime`	`float`	Time when this effect was spawned (in seconds since engine start)
`SourceNotifyName`	`FString`	Name of the animation notify that spawned this effect

Methods:

IsValid() -> bool: Returns true if the component is still valid and active

Usage Patterns

Basic Tag-Based Effect Control

// Setup: Register effects through animation notifies with bRegisterWithListener = true

// Game logic: Change tags based on game state
Event OnPlayerEnterCombat()
{
    GameplayTagContainer CombatTags;
    CombatTags.AddTag("Combat.Active");
    CombatTags.AddTag("Player.State.Combat");
    DNAListener.AddGameplayTags(CombatTags);
}

Event OnPlayerExitCombat()
{
    GameplayTagContainer CombatTags;
    CombatTags.AddTag("Combat.Active");
    CombatTags.AddTag("Player.State.Combat");
    DNAListener.RemoveGameplayTags(CombatTags, EGameplayTagRemovalMode::ExactMatch);
}

Monitoring and Debugging

// Enable logging for debugging
DNAListener.bLogParameterChanges = true;

// Monitor effect count
Event Tick()
{
    int32 EffectCount = DNAListener.GetActiveEffectCount();
    if (EffectCount > MaxAllowedEffects)
    {
        DNAListener.CleanupInactiveEffects();
    }
}

// React to parameter updates
function OnParametersUpdated(ActiveTags: GameplayTagContainer, AppliedOverrides: Array<NiagaraParameterOverride>)
{
    // Log or react to parameter changes
    PrintString("Parameter update - Tag count: " + string(ActiveTags.Num()) + 
                ", Override count: " + string(AppliedOverrides.Length));
}

Network Considerations

// Only modify tags on authority
function ChangePlayerState(NewState: GameplayTag)
{
    if (DNAListener.HasNetworkAuthority())
    {
        GameplayTagContainer NewTags;
        NewTags.AddTag(NewState);
        DNAListener.UpdateGameplayTags(NewTags);
    }
    else
    {
        // On clients, tags will be replicated from server
        PrintString("Waiting for server tag update...");
    }
}

Performance Considerations

Cleanup Management

Auto Cleanup: Enable bAutoCleanupInactiveEffects for automatic management
Manual Cleanup: Disable auto cleanup and call CleanupInactiveEffects() during appropriate game moments
Cleanup Interval: Adjust CleanupInterval based on effect spawn frequency

Core Concept​

Essential Methods​

Optional Utility Methods​

Overview​

Component Setup​

Adding to an Actor​

Basic Configuration​

Blueprint API Reference​

Network Authority​

HasNetworkAuthority​

Gameplay Tag Management​

AddGameplayTags​

UpdateGameplayTags​

RemoveGameplayTags​

GetTagsWithDescendants​

Effect Management​

RegisterNiagaraEffect​

UnregisterNiagaraEffect​

RefreshAllEffects​

CleanupInactiveEffects​

Queries and Getters​

GetActiveGameplayTags​

GetActiveNiagaraComponents​

GetActiveEffectCount​

GetActiveEffects​

Events​

OnParametersUpdated​

Data Types​

EGameplayTagRemovalMode​

FActiveNiagaraEffectInfo​

Usage Patterns​

Basic Tag-Based Effect Control​

Monitoring and Debugging​

Network Considerations​

Performance Considerations​

Cleanup Management​

Core Concept

Essential Methods

Optional Utility Methods

Overview

Component Setup

Adding to an Actor

Basic Configuration

Blueprint API Reference

Network Authority

HasNetworkAuthority

Gameplay Tag Management

AddGameplayTags

UpdateGameplayTags

RemoveGameplayTags

GetTagsWithDescendants

Effect Management

RegisterNiagaraEffect

UnregisterNiagaraEffect

RefreshAllEffects

CleanupInactiveEffects

Queries and Getters

GetActiveGameplayTags

GetActiveNiagaraComponents

GetActiveEffectCount

GetActiveEffects

Events

OnParametersUpdated

Data Types

EGameplayTagRemovalMode

FActiveNiagaraEffectInfo

Usage Patterns

Basic Tag-Based Effect Control

Monitoring and Debugging

Network Considerations

Performance Considerations

Cleanup Management