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> Unreal Engine API Reference > Plugins > Niagara > UNiagaraComponent

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UNiagaraComponent

[UNiagaraComponent](API\Plugins\Niagara\UNiagaraComponent) is the primitive component for a Niagara System.

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Inheritance Hierarchy

UObjectBase

UObjectBaseUtility

UObject

UActorComponent

USceneComponent

UPrimitiveComponent

UFXSystemComponent

UNiagaraComponent

UNiagaraCullProxyComponent

References

Module	Niagara
Header	/Engine/Plugins/FX/Niagara/Source/Niagara/Public/NiagaraComponent.h
Include	#include "NiagaraComponent.h"

Syntax

UCLASS(ClassGroup=(Rendering, Common), HideCategories=Object, HideCategories=Physics,
HideCategories=Collision, ShowCategories=Trigger, EditInlineNew,
Meta=(BlueprintSpawnableComponent, DisplayName="Niagara Particle System Component"))
class UNiagaraComponent : public UFXSystemComponent

Remarks

UNiagaraComponent is the primitive component for a Niagara System.

Variables

	Name	Description
EAttachmentRule	AutoAttachLocationRule	Options for how we handle our location when we attach to the AutoAttachParent, if bAutoManageAttachment is true.
TWeakObjectPtr<...	AutoAttachParent	Component we automatically attach to when activated, if bAutoManageAttachment is true.
EAttachmentRule	AutoAttachRotationRule	Options for how we handle our rotation when we attach to the AutoAttachParent, if bAutoManageAttachment is true.
EAttachmentRule	AutoAttachScaleRule	Options for how we handle our scale when we attach to the AutoAttachParent, if bAutoManageAttachment is true.
FName	AutoAttachSocketName	Socket we automatically attach to on the AutoAttachParent, if bAutoManageAttachment is true.
uint32: 1	bAutoAttachWeldSimulatedBodies	Option for how we handle bWeldSimulatedBodies when we attach to the AutoAttachParent, if bAutoManageAttachment is true.
uint32: 1	bAutoManageAttachment	True if we should automatically attach to AutoAttachParent when activated, and detach from our parent when completed.
uint32: 1	bEnablePreviewLODDistance
uint32: 1	bWaitForCompilationOnActivate
FNiagaraScalabi...	DebugCachedScalabilityState	Cache our scalability state in the component so we have access to it easily and also after it has been removed from the scalability manager.
float	MaxTimeBeforeForceUpdateTransform	Time between forced UpdateTransforms for systems that use dynamically calculated bounds, Which is effectively how often the bounds are shrunk.
FOnNiagaraSyste...	OnSystemFinished	Called when the particle system is done.
ENCPoolMethod	PoolingMethod	How to handle pooling for this component instance.
float	PreviewLODDistance
float	PreviewMaxDistance

Constructors

	Name	Description
	UNiagaraComponent ( const FObjectInitializer& ObjectIn... )

Functions

	Name	Description
void	AdvanceSimulation ( int32 TickCount, float TickDeltaSeconds )	Advances this system's simulation by the specified number of ticks and delta time.
void	AdvanceSimulationByTime ( float SimulateTime, float TickDeltaSeconds )	Advances this system's simulation by the specified time in seconds and delta time.
void	BeginUpdateContextReset()
void	ClearEmitterFixedBounds ( FName EmitterName )	Clear any previously set fixed bounds for the emitter instance.
void	ClearSystemFixedBounds()	Clear any previously set fixed bounds for the system instance.
void	DestroyInstance()
void	EndUpdateContextReset()
void	EnsureOverrideParametersConsistent()
FNiagaraVari...	FindParameterOverride ( const FNiagaraVariableBase& InKey )	Find the value of an overridden parameter.
ENiagaraAgeU...	GetAgeUpdateMode()
bool	GetAllowScalability()
UNiagaraSyst...	GetAsset()
FNiagaraVari...	GetCurrentParameterValue ( const FNiagaraVariableBase& InKey )	Gets the current value of a parameter which is being used by the simulation.
float	GetCustomTimeDilation()
float	GetDesiredAge()	Gets the desired age of the System instance.
FBox	GetEmitterFixedBounds ( FName EmitterName )	Gets the fixed bounds for an emitter instance.
ENiagaraExec...	GetExecutionState()
bool	GetForceLocalPlayerEffect()
bool	GetForceSolo()
bool	GetLockDesiredAgeDeltaTimeToSeekDelta()	Gets whether or not the delta time used to tick the system instance when using desired age is locked to the seek delta.
float	GetMaxSimTime()	Get the maximum CPU time in seconds we will simulate to the desired age, when we go beyond this limit ticks will be processed in the next frame.
TArray< FVec...	GetNiagaraParticlePositions_DebugOnly ( const FString& InEmitterName )	Debug accessors for getting positions in blueprints.
TArray< floa...	GetNiagaraParticleValues_DebugOnly ( const FString& InEmitterName, const FString& InValueName )	Debug accessors for getting a float attribute array in blueprints.
TArray< FVec...	GetNiagaraParticleValueVec3_DebugOnly ( const FString& InEmitterName, const FString& InValueName )	Debug accessors for getting a FVector attribute array in blueprints.
FNiagaraUser...	GetOverrideParameters()
const FNiaga...	GetOverrideParameters()
FParticlePer...	GetPerfStatsContext()
float	GetPreviewLODDistance()
bool	GetPreviewLODDistanceEnabled()
int32	GetRandomSeedOffset()
bool	GetRenderingEnabled()	Gets whether or not rendering is enabled for this component.
ENiagaraExec...	GetRequestedExecutionState()
float	GetSafeTimeSinceRendered ( float WorldTime )
int32	GetScalabilityManagerHandle()
float	GetSeekDelta()	Gets the delta value which is used when seeking from the current age, to the desired age.
FBox	GetSystemFixedBounds()	Gets the fixed bounds for the system instance.
FNiagaraSyst...	GetSystemInstanceController()
FNiagaraSyst...	GetSystemInstanceController()
ENiagaraTick...	GetTickBehavior()
bool	HasParameterOverride ( const FNiagaraVariableBase& InKey )
void	InitForPerformanceBaseline()	Initializes this component for capturing a performance baseline.
bool	InitializeSystem()
bool	IsComplete()
bool	IsLocalPlayerEffect()	Is this an effect on or linked to the local player.
bool	IsPaused()
bool	IsRegisteredWithScalabilityManager()
bool	IsUsingCullProxy()
bool	IsWorldReadyToRun()
void	OnPooledReuse ( UWorld* NewWorld )
FOnSynchroni...	OnSynchronizedWithAssetParameters()
FOnSystemIns...	OnSystemInstanceChanged()
void	PostLoadNormalizeOverrideNames()
void	ReinitializeSystem()	Called on when an external object wishes to force this System to reinitialize itself from the System data.
void	RemoveParameterOverride ( const FNiagaraVariableBase& InKey )	Remove an override for a given parameter if one exists.
void	ResetSystem()	Resets the System to it's initial pre-simulated state.
bool	ResolveOwnerAllowsScalability ( bool bRegister )
void	SeekToDesiredAge ( float InDesiredAge )	Sets the desired age of the System instance and designates that this change is a seek.
void	SetAgeUpdateMode ( ENiagaraAgeUpdateMode InAgeUpdateMo... )	Sets the age update mode for the System instance.
void	SetAllowScalability ( bool bAllow )	Set whether this component is allowed to perform scalability checks and potentially be culled etc.
void	SetAsset ( UNiagaraSystem* InAsset, bool bResetExistingOverrideParamete... )	Switch which asset the component is using.
void	SetAutoDestroy ( bool bInAutoDestroy )
void	SetCanRenderWhileSeeking ( bool bInCanRenderWhileSeeking )	Sets whether or not the system can render while seeking.
void	SetCustomTimeDilation ( float Dilation )	Sets the custom time dilation value for the component.
void	SetDesiredAge ( float InDesiredAge )	Sets the desired age of the System instance.
void	SetEmitterFixedBounds ( FName EmitterName, FBox LocalBounds )	Sets the fixed bounds for an emitter instance, this overrides all other bounds.
void	SetForceLocalPlayerEffect ( bool bIsPlayerEffect )
void	SetForceSolo ( bool bInForceSolo )
void	SetGpuComputeDebug ( bool bEnableDebug )
void	SetLockDesiredAgeDeltaTimeToSeekDelta ( bool bLock )	Sets whether or not the delta time used to tick the system instance when using desired age is locked to the seek delta.
void	SetLODDistance ( float InLODDistance, float InMaxLODDistance )
void	SetMaxSimTime ( float InMaxTime )	Sets the maximum CPU time in seconds we will simulate to the desired age, when we go beyond this limit ticks will be processed in the next frame.
void	SetNiagaraVariableActor ( const FString& InVariableName, AActor* Actor )
void	SetNiagaraVariableBool ( const FString& InVariableName, bool InValue )	Sets a Niagara float parameter by name, overriding locally if necessary.
void	SetNiagaraVariableFloat ( const FString& InVariableName, float InValue )	Sets a Niagara float parameter by name, overriding locally if necessary.
void	SetNiagaraVariableInt ( const FString& InVariableName, int32 InValue )	Sets a Niagara int parameter by name, overriding locally if necessary.
void	SetNiagaraVariableLinearColor ( const FString& InVariableName, const FLinearColor& InValue )	Sets a Niagara FLinearColor parameter by name, overriding locally if necessary.
void	SetNiagaraVariableObject ( const FString& InVariableName, UObject* Object )
void	SetNiagaraVariablePosition ( const FString& InVariableName, FVector InValue )	Sets a Niagara Position parameter by name, overriding locally if necessary.
void	SetNiagaraVariableQuat ( const FString& InVariableName, const FQuat& InValue )	Sets a Niagara Vector3 parameter by name, overriding locally if necessary.
void	SetNiagaraVariableVec2 ( const FString& InVariableName, FVector2D InValue )	Sets a Niagara Vector3 parameter by name, overriding locally if necessary.
void	SetNiagaraVariableVec3 ( const FString& InVariableName, FVector InValue )	Sets a Niagara Vector3 parameter by name, overriding locally if necessary.
void	SetNiagaraVariableVec4 ( const FString& InVariableName, const FVector4& InValue )	Sets a Niagara Vector4 parameter by name, overriding locally if necessary.
void	SetParameterOverride ( const FNiagaraVariableBase& InKey, const FNiagaraVariant& InValue )
void	SetPaused ( bool bInPaused )
void	SetPreviewLODDistance ( bool bEnablePreviewLODDistance, float PreviewLODDistance, float PreviewMaxDistance )
void	SetRandomSeedOffset ( int32 NewRandomSeedOffset )
void	SetRenderingEnabled ( bool bInRenderingEnabled )	Sets whether or not rendering is enabled for this component.
void	SetSeekDelta ( float InSeekDelta )	Sets the delta value which is used when seeking from the current age, to the desired age.
void	SetSystemFixedBounds ( FBox LocalBounds )	Sets the fixed bounds for the system instance, this overrides all other bounds.
void	SetSystemSignificanceIndex ( int32 InIndex )	The significant index for this component.
void	SetTickBehavior ( ENiagaraTickBehavior NewTickBehavio... )
void	SetUserParametersToDefaultValues()	Removes all local overrides and replaces them with the values from the source System -
void	SetVariableActor ( FName InVariableName, AActor* Actor )
void	SetVariableBool ( FName InVariableName, bool InValue )	Sets a Niagara float parameter by name, overriding locally if necessary.
void	SetVariableFloat ( FName InVariableName, float InValue )	Sets a Niagara float parameter by name, overriding locally if necessary.
void	SetVariableInt ( FName InVariableName, int32 InValue )	Sets a Niagara int parameter by name, overriding locally if necessary.
void	SetVariableLinearColor ( FName InVariableName, const FLinearColor& InValue )	Sets a Niagara FLinearColor parameter by name, overriding locally if necessary.
void	SetVariableMaterial ( FName InVariableName, UMaterialInterface* Object )
void	SetVariableObject ( FName InVariableName, UObject* Object )
void	SetVariablePosition ( FName InVariableName, FVector InValue )	Sets a Niagara Position parameter by name, overriding locally if necessary.
void	SetVariableQuat ( FName InVariableName, const FQuat& InValue )	Sets a Niagara Vector3 parameter by name, overriding locally if necessary.
void	SetVariableStaticMesh ( FName InVariableName, UStaticMesh* InValue )
void	SetVariableTexture ( FName InVariableName, UTexture* Texture )
void	SetVariableTextureRenderTarget ( FName InVariableName, UTextureRenderTarget* TextureR... )
void	SetVariableVec2 ( FName InVariableName, FVector2D InValue )	Sets a Niagara Vector3 parameter by name, overriding locally if necessary.
void	SetVariableVec3 ( FName InVariableName, FVector InValue )	Sets a Niagara Vector3 parameter by name, overriding locally if necessary.
void	SetVariableVec4 ( FName InVariableName, const FVector4& InValue )	Sets a Niagara Vector4 parameter by name, overriding locally if necessary.
void	UpgradeDeprecatedParameterOverrides()

Overridden from UFXSystemComponent

	Name	Description
void	ActivateSystem ( bool bFlagAsJustAttached )
void	DeactivateImmediate()	Forces component to deactivate immediately.
uint32	GetApproxMemoryUsage()	Returns an approximate memory usage value for this component.
UFXSystemAss...	GetFXSystemAsset()	Get the referenced FXSystem asset.
void	ReleaseToPool()	Deactivates this system and releases it to the pool on completion.
void	SetActorParameter ( FName ParameterName, AActor* Param )	Set a named actor instance parameter on this ParticleSystemComponent.
void	SetAutoAttachmentParameters ( USceneComponent* Parent, FName SocketName, EAttachmentRule LocationRule, EAttachmentRule RotationRule, EAttachmentRule ScaleRule )	Set AutoAttachParent, AutoAttachSocketName, AutoAttachLocationRule, AutoAttachRotationRule, AutoAttachScaleRule to the specified parameters.
void	SetBoolParameter ( FName ParameterName, bool Param )	Change a named boolean parameter, ParticleSystemComponent converts to float.
void	SetColorParameter ( FName ParameterName, FLinearColor Param )	Set a named color instance parameter on this ParticleSystemComponent.
void	SetEmitterEnable ( FName EmitterName, bool bNewEnableState )	Enables/Disables a sub-emitter
void	SetFloatParameter ( FName ParameterName, float Param )	Change a named float parameter
void	SetIntParameter ( FName ParameterName, int Param )	Change a named int parameter
void	SetUseAutoManageAttachment ( bool bAutoManage )	Sets whether we should automatically attach to AutoAttachParent when activated, and detach from our parent when completed.
void	SetVectorParameter ( FName ParameterName, FVector Param )	Set a named vector instance parameter on this ParticleSystemComponent.

Overridden from UPrimitiveComponent

	Name	Description
FPrimitiveSc...	CreateSceneProxy()	Creates a proxy to represent the primitive to the scene manager in the rendering thread.
int32	GetNumMaterials()	Return number of material elements in this primitive
void	GetUsedMaterials ( TArray< UMaterialInterface* > ..., bool bGetDebugMaterials )	Retrieves the materials used in this component

Overridden from USceneComponent

	Name	Description
FBoxSphereBo...	CalcBounds ( const FTransform& LocalToWorld )	Calculate the bounds of the component. Default behavior is a bounding box/sphere of zero size.
bool	IsVisible()	Returns true if this component is visible in the current context
void	OnAttachmentChanged()	Called when AttachParent changes, to allow the scene to update its attachment state.
void	OnChildAttached ( USceneComponent* ChildComponen... )	Called after a child scene component is attached to this component.
void	OnChildDetached ( USceneComponent* ChildComponen... )	Called after a child scene component is detached from this component.

Overridden from UActorComponent

	Name	Description
void	Activate ( bool bReset )	Activates the SceneComponent, should be overridden by native child classes.
const UObjec...	AdditionalStatObject()	Give a readable name for this component, including asset name if applicable
void	CreateRenderState_Concurrent ( FRegisterComponentContext* Con... )	Used to create any rendering thread information for this component
void	Deactivate()	Deactivates the SceneComponent.
void	DestroyRenderState_Concurrent()	Used to shut down any rendering thread structure for this component
bool	IsReadyForOwnerToAutoDestroy()	Overridable check for a component to indicate to its Owner that it should prevent the Actor from auto destroying when finished
void	OnComponentCreated()	Called when a component is created (not loaded). This can happen in the editor or during gameplay
void	OnComponentDestroyed ( bool bDestroyingHierarchy )	Called when a component is destroyed
void	OnEndOfFrameUpdateDuringTick()	Allows components to handle an EOF update happening mid tick.
void	OnRegister()	Called when a component is registered, after Scene is set, but before CreateRenderState_Concurrent or OnCreatePhysicsState are called.
void	OnUnregister()	Called when a component is unregistered.
void	PostApplyToComponent()	Called after ApplyToComponent has run.
void	SendRenderDynamicData_Concurrent()	Called to send dynamic data for this component to the rendering thread
void	TickComponent ( float DeltaTime, enum ELevelTick TickType, FActorComponentTickFunction* T... )	Function called every frame on this ActorComponent.

Overridden from UObject

	Name	Description
void	BeginDestroy()	Called before destroying the object.
void	PostEditChangeProperty ( FPropertyChangedEvent& PropertyCha... )	Called when a property on this object has been modified externally
void	PostLoad()	Do any object-specific cleanup required immediately after loading an object.
void	PreEditChange ( FProperty* PropertyAboutToChan... )	This is called when a property is about to be modified externally
void	Serialize ( FStructuredArchive::FRecord Record )	Handles reading, writing, and reference collecting using FArchive.

Typedefs

Name	Description
FOnSynchronizedWithAssetParameters
FOnSystemInstanceChanged

Deprecated Functions

	Name	Description
UNiagaraData...	GetDataInterface ( const FString& Name )	This method will be removed in a future release. Use the method provided by the Niagara Function Library instead.
FNiagaraSyst...	GetSystemInstance()	This interface is no longer safe to access directly. Use the interface provided by GetSystemInstanceController instead.
TSharedPtr< ...	GetSystemSimulation()	This interface is no longer safe to access directly. Use the interface provided by GetSystemInstanceController instead.