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> Unreal Engine API Reference > Runtime > Engine > Particles > UParticleSystemComponent

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UParticleSystemComponent

A particle emitter.

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Inheritance Hierarchy

UObjectBase

UObjectBaseUtility

UObject

UActorComponent

USceneComponent

UPrimitiveComponent

UFXSystemComponent

UParticleSystemComponent

UCascadeParticleSystemComponent

References

Module	Engine
Header	/Engine/Source/Runtime/Engine/Classes/Particles/ParticleSystemComponent.h
Include	#include "Particles/ParticleSystemComponent.h"

Syntax

class UParticleSystemComponent : public UFXSystemComponent

Remarks

A particle emitter.

Variables

	Name	Description
float	AccumLODDistanceCheckTime	LOD updating...
float	AccumTickTime	Used to accumulate total tick time to determine whether system can be skipped ticking if not visible.
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.
uint8: 1	bAllowRecycling	If true, this Particle System will be available for recycling after it has completed.
uint8: 1	bAutoAttachWeldSimulatedBodies	Option for how we handle bWeldSimulatedBodies when we attach to the AutoAttachParent, if bAutoManageAttachment is true.
uint8: 1	bAutoDestroy
uint8: 1	bAutoManageAttachment	True if we should automatically attach to AutoAttachParent when activated, and detach from our parent when completed.
uint8: 1	bDeactivateTriggered	If true, someone has requested this component deactivate.
uint8: 1	bForcedInActive	This is set when any of our "don't tick me" timeout values have fired
uint8: 1	bForceLODUpdateFromRenderer	If true, force an LOD update from the renderer.
uint8: 1	bHasBeenActivated	This flag will be set the first time the PSysComp is activated...
uint8: 1	bIsManagingSignificance	If this component is having it's significance managed by gameplay code.
uint8: 1	bIsViewRelevanceDirty	If true, the ViewRelevanceFlags are dirty and should be recached
uint8: 1	bJustRegistered	Indicates that the component has not been ticked since being registered.
bool	bOldPositionValid
uint8: 1	bOverrideLODMethod	Indicates that the component's LODMethod overrides the Template's
uint8: 1	bResetOnDetach
uint8: 1	bResetTriggered	If true, someone has requested this component reset.
uint8: 1	bSkipUpdateDynamicDataDuringTick	Flag indicating that dynamic updating of render data should NOT occur during Tick.
uint8: 1	bSuppressSpawning
uint8: 1	bUpdateOnDedicatedServer	Whether to update the particle system on dedicated servers
TArray< struct ...	BurstEvents	The Burst events that occurred in this PSysComp.
uint8: 1	bWarmingUp
uint8: 1	bWasActive	True if this was active before being unregistered or otherwise reset, if so reactivate it
uint8: 1	bWasCompleted
uint8: 1	bWasDeactivated
uint8: 1	bWasManagingSignificance	If this component was previously having it's significance managed by gameplay code.
TArray< FMateri...	CachedViewRelevanceFlags	The view relevance flags for each LODLevel.
TArray< struct ...	CollisionEvents	The Collision events that occurred in this PSysComp.
float	CustomTimeDilation	Scales DeltaTime in UParticleSystemComponent::Tick(...)
TArray< struct ...	DeathEvents	The Death events that occurred in this PSysComp.
int32	EditorDetailMode	Used for applying Cascade's detail mode setting to in-level particle systems
int32	EditorLODLevel	Used by the editor to set the LODLevel
float	EmitterDelay	This is created at start up and then added to each emitter
TArray< struct ...	EmitterInstances
TArray< TObject...	EmitterMaterials
FFXSystem *	FXSystem
TArray< struct ...	InstanceParameters	Array holding name instance parameters for this ParticleSystemComponent.
TArray< struct ...	KismetEvents	The Kismet events that occurred for this PSysComp.
float	LastSignificantTime	Time in seconds since we were last considered significant.
TEnumAsByte< en...	LODMethod	The method of LOD level determination to utilize for this particle system
float	MaxTimeBeforeForceUpdateTransform	Time between forced UpdateTransforms for systems that use dynamically calculated bounds, Which is effectively how often the bounds are shrunk.
FVector	OldPosition
FParticleBurstS...	OnParticleBurst
FParticleCollis...	OnParticleCollide
FParticleDeathS...	OnParticleDeath
FParticleSpawnS...	OnParticleSpawn
FOnSystemFinish...	OnSystemFinished	Called when the particle system is done.
FVector	PartSysVelocity
EPSCPoolMethod	PoolingMethod	If this PSC is pooling.
FRandomStream	RandomStream	Stream of random values to use with this component
FRenderCommandF...	ReleaseResourcesFence	Command fence used to shut down properly
int32	ReplayClipIDNumber	Clip ID number we're either playing back or capturing to, depending on the value of ReplayState.
TArray< TObject...	ReplayClips	Array of replay clips for this particle system component.
int32	ReplayFrameIndex	The current replay frame for playback
TEnumAsByte< en...	ReplayState	Current particle 'replay state'.
EParticleSignif...	RequiredSignificance	The significance this component requires of it's emitters for them to be enabled.
float	SecondsBeforeInactive	Number of seconds of emitter not being rendered that need to pass before it no longer gets ticked/ becomes inactive.
TArray< TObject...	SkelMeshComponents	The skeletal mesh components used with the socket location module.
TArray< struct ...	SpawnEvents	The Spawn events that occurred in this PSysComp.
TObjectPtr< cla...	Template
float	WarmupTickRate
float	WarmupTime

Constructors

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

Functions

	Name	Description
void	AutoPopulateInstanceProperties()	Auto-populate the instance parameters based on contained modules.
void	BeginTrails ( FName InFirstSocketName, FName InSecondSocketName, ETrailWidthMode InWidthMode, float InWidth )	Begins all trail emitters in this component.
bool	CanBeOccluded()	True if this component can be occluded.
bool	CanConsiderInvisible()	True if this component can be considered invisible and potentially culled.
bool	CanSkipTickDueToVisibility()
bool	CanTickInAnyThread()	Return true if this psys can tick in any thread
void	ClearDynamicData()	Clears dynamic data on the rendering thread.
void	ClearParameter ( FName ParameterName, enum EParticleSysParamType Paramete... )	Clears the specified parameter, returning it to the default value set in the template
void	Complete()
void	ComputeCanTickInAnyThread()	Decide if this psys can tick in any thread, and set bIsElligibleForAsyncTick
void	ComputeTickComponent_Concurrent()	Possibly parallel phase of TickComponent
void	ConditionalCacheViewRelevanceFlags ( UParticleSystem* NewTemplate )	Cache the view-relevance for each emitter at each LOD level if needed.
FParticleDyn...	CreateDynamicData ( ERHIFeatureLevel::Type InFeatureLev... )	Creates dynamic particle data for rendering the particle system this frame.
FDynamicEmit...	CreateDynamicDataFromReplay ( FParticleEmitterInstance* Emit..., const FDynamicEmitterReplayDataBase..., bool bSelected, ERHIFeatureLevel::Type InFeatureLev... )	Static: Supplied with a chunk of replay data, this method will create dynamic emitter data that can be used to render the particle system
UMaterialIns...	CreateNamedDynamicMaterialInstance ( FName InName, UMaterialInterface* SourceMate... )	Creates a Dynamic Material Instance for the specified named material override, optionally from the supplied material.
void	DeactivaateNextTick()
void	DeactivateSystem()	Deactivate the system
int32	DetermineLODLevelForLocation ( const FVector& EffectLocation )	This will determine which LOD to use based off the specific ParticleSystem passed in and the distance to where that PS is being displayed.
bool	Editor_CanBeTickManaged()
void	EndTrails()	Ends all trail emitters in this component.
void	FinalizeTickComponent()	After the possibly parallel phase of TickComponent, we fire events, etc
UParticleSys...	FindReplayClipForIDNumber ( const int32 InClipIDNumber )	Finds the replay clip of the specified ID number
void	ForceAsyncWorkCompletion ( EForceAsyncWorkCompletion Behavior, bool bDefinitelyGameThread )	If there is async work outstanding, force it to be completed now
void	ForceAsyncWorkCompletion ( EForceAsyncWorkCompletion Behavior, bool bDefinitelyGameThread, bool InSkipUpdateDynamicDataDuringT... )	If there is async work outstanding, force it to be completed now
void	ForceReset()
void	ForceUpdateBounds()	Force the component to update its bounding box.
void	GenerateParticleEvent ( const FName InEventName, const float InEmitterTime, const FVector InLocation, const FVector InDirection, const FVector InVelocity )	Record a kismet event.
bool	GetActorParameter ( const FName InName, AActor*& OutActor )	Retrieve the Actor parameter value for the given name.
bool	GetAnyVectorParameter ( const FName InName, FVector& OutVector )	Retrieve the Vector parameter value for the given name...also looks for colors and floats and returns those
float	GetApproxDistanceSquared ( FVector Point )	Returns the approximate distance squared from this component to the passed location.
const FBoxSp...	GetAsyncBounds()
const FTrans...	GetAsyncComponentToWorld()
const TArray...	GetAsyncInstanceParameters()
const FVecto...	GetAsyncPartSysVelocity()
bool	GetBeamEndPoint ( int32 EmitterIndex, FVector& OutEndPoint )	Get the beam end point
bool	GetBeamSourcePoint ( int32 EmitterIndex, int32 SourceIndex, FVector& OutSourcePoint )	Get the beam source point
bool	GetBeamSourceStrength ( int32 EmitterIndex, int32 SourceIndex, float& OutSourceStrength )	Get the beam source strength
bool	GetBeamSourceTangent ( int32 EmitterIndex, int32 SourceIndex, FVector& OutTangentPoint )	Get the beam source tangent
bool	GetBeamTargetPoint ( int32 EmitterIndex, int32 TargetIndex, FVector& OutTargetPoint )	Get the beam target point
bool	GetBeamTargetStrength ( int32 EmitterIndex, int32 TargetIndex, float& OutTargetStrength )	Get the beam target strength
bool	GetBeamTargetTangent ( int32 EmitterIndex, int32 TargetIndex, FVector& OutTangentPoint )	Get the beam target tangent
bool	GetColorParameter ( const FName InName, FLinearColor& OutColor )	Retrieve the Color parameter value for the given name.
int32	GetCurrentDetailMode()	Decide which detail mode should be applied to this particle system.
int32	GetCurrentLODIndex()
bool	GetFloatParameter ( const FName InName, float& OutFloat )	Retrieve the Float parameter value for the given name.
int32	GetLODLevel()	Get the LOD level of the particle system
const FVecto...	GetLWCTile()
int32	GetManagerHandle()
FPSCTickData...	GetManagerTickData()
bool	GetMaterialParameter ( const FName InName, UMaterialInterface*& OutMateri... )	Retrieve the Material parameter value for the given name.
UMaterialInt...	GetNamedMaterial ( FName InName )	Returns a named material. If this named material is not found, returns NULL.
int32	GetNamedMaterialIndex ( FName InName )	Returns the index into the EmitterMaterials array for this named.
FName	GetNameForMaterial ( UMaterialInterface* InMaterial )	Returns the name associated with the passed in material, returns NAME_None if it is not found
int32	GetNumActiveParticles()	Get the current number of active particles in this system
void	GetOwnedTrailEmitters ( TrailEmitterArray& OutTrailEmitter..., const void* InOwner, bool bSetOwner )	Fills the passed array with all trail emitters associated with a particular object.
FParticlePer...	GetPerfStatsContext()
const TArray...	GetPlayerLocations()
const TArray...	GetPlayerLODDistanceFactor()
bool	GetVectorParameter ( const FName InName, FVector& OutVector )	Retrieve the Vector parameter value for the given name.
FParticleSys...	GetWorldManager()
bool	HasCompleted()
void	InitializeSystem()
void	InitParticles()	If particles have not already been initialised (ie. EmitterInstances created) do it now.
int32	IsPendingManagerAdd()
int32	IsPendingManagerRemove()
bool	IsTickManaged()
void	KillParticlesForced()
void	MarshalParamsForAsyncTick()
void	OnSignificanceChanged ( bool bSignificant, bool bApplyToEmitters, bool bAsync )	When the overall significance for the component is changed.
void	OrientZAxisTowardCamera()	Orients the Z axis of the ParticleSystemComponent toward the camera while preserving the X axis direction
bool	ParticleLineCheck ( FHitResult& Hit, AActor* SourceActor, const FVector& End, const FVector& Start, const FVector& HalfExtent, const FCollisionObjectQueryParams&... )	Collision Handling...
void	ReportEventBurst ( const FName InEventName, const float InEmitterTime, const int32 ParticleCount, const FVector InLocation, const TArray< class UParticleModule... )	Record a bursting event.
void	ReportEventCollision ( const FName InEventName, const float InEmitterTime, const FVector InLocation, const FVector InDirection, const FVector InVelocity, const TArray< class UParticleModule..., const float InParticleTime, const FVector InNormal, const float InTime, const int32 InItem, const FName InBoneName, UPhysicalMaterial* PhysMat )	Record a collision event.
void	ReportEventDeath ( const FName InEventName, const float InEmitterTime, const FVector InLocation, const FVector InVelocity, const TArray< class UParticleModule..., const float InParticleTime )	Record a death event.
void	ReportEventSpawn ( const FName InEventName, const float InEmitterTime, const FVector InLocation, const FVector InVelocity, const TArray< class UParticleModule... )	Event reporting... Record a spawning event.
void	ResetBurstLists()
void	ResetNextTick()
void	ResetParticles ( bool bEmptyInstances )
void	ResetToDefaults()	Stops the emitter, unregisters the component, and resets the component's properties to the values of its template
void	RewindEmitterInstances()
void	SetAutoAttachParams ( USceneComponent* Parent, FName SocketName, EAttachLocation::Type LocationType )	DEPRECATED: Set AutoAttachParent, AutoAttachSocketName, AutoAttachLocationType to the specified parameters.
void	SetBeamEndPoint ( int32 EmitterIndex, FVector NewEndPoint )	Beam-related script functions. Set the beam end point
void	SetBeamSourcePoint ( int32 EmitterIndex, FVector NewSourcePoint, int32 SourceIndex )	Set the beam source point
void	SetBeamSourceStrength ( int32 EmitterIndex, float NewSourceStrength, int32 SourceIndex )	Set the beam source strength
void	SetBeamSourceTangent ( int32 EmitterIndex, FVector NewTangentPoint, int32 SourceIndex )	Set the beam source tangent
void	SetBeamTargetPoint ( int32 EmitterIndex, FVector NewTargetPoint, int32 TargetIndex )	Set the beam target point
void	SetBeamTargetStrength ( int32 EmitterIndex, float NewTargetStrength, int32 TargetIndex )	Set the beam target strength
void	SetBeamTargetTangent ( int32 EmitterIndex, FVector NewTangentPoint, int32 TargetIndex )	Set the beam target tangent
void	SetFloatRandParameter ( FName ParameterName, float Param, float ParamLow )	Set a named random float instance parameter on this ParticleSystemComponent.
void	SetLODLevel ( int32 InLODLevel )	Set the LOD level of the particle system
void	SetManagerHandle ( int32 InHandle )
void	SetManagingSignificance ( bool bManageSignificance )	Called from game code when the component begins having it's significance managed.
void	SetMaterialParameter ( FName ParameterName, UMaterialInterface* Param )	Set a named material instance parameter on this ParticleSystemComponent.
void	SetPendingManagerAdd ( bool bValue )
void	SetPendingManagerRemove ( bool bValue )
void	SetRequiredSignificance ( EParticleSignificanceLevel NewRequi... )	Called from game code when the significance required for a component changes.
void	SetTemplate ( UParticleSystem* NewTemplate )	Change the ParticleSystem used by this ParticleSystemComponent
void	SetTrailSourceData ( FName InFirstSocketName, FName InSecondSocketName, ETrailWidthMode InWidthMode, float InWidth )	Sets the defining data for all trails in this component.
void	SetVectorRandParameter ( FName ParameterName, const FVector& Param, const FVector& ParamLow )	Set a named random vector instance parameter on this ParticleSystemComponent.
void	SetVectorUnitRandParameter ( FName ParameterName, const FVector& Param, const FVector& ParamLow )	Set a named random unit vector instance parameter on this ParticleSystemComponent.
bool	ShouldBeTickManaged()
bool	ShouldManageSignificance()	Whether this component should have it's significance managed by game code.
void	UpdateDynamicData()
void	UpdateInstances ( bool bEmptyInstances )
void	UpdateLODInformation()

Overridden from UFXSystemComponent

	Name	Description
void	ActivateSystem ( bool bFlagAsJustAttached )	Activate the system
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 )	Set a named float instance parameter on this ParticleSystemComponent.
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 )	Set a named float instance parameter on this ParticleSystemComponent.
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.
FBodyInstanc...	GetBodyInstance ( FName BoneName, bool bGetWelded, int32 Index )	Returns BodyInstance of the component.
UMaterialInt...	GetMaterial ( int32 ElementIndex )	Returns the material used by the element at the specified index
int32	GetNumMaterials()	Return number of material elements in this primitive
void	GetStreamingRenderAssetInfo ( FStreamingTextureLevelContext& Lev..., TArray< FStreamingRenderAssetPrimit... )	Enumerates the streaming textures/meshes used by the primitive.
void	GetUsedMaterials ( TArray< UMaterialInterface* > ..., bool bGetDebugMaterials )	Retrieves the materials used in this component
void	SetMaterial ( int32 ElementIndex, UMaterialInterface* Material )	Changes the material applied to an element of the mesh.
void	SetMaterialByName ( FName MaterialSlotName, UMaterialInterface* Material )	Changes the material applied to an element of the mesh.

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	GetMaterialPropertyPath ( int32 ElementIndex, UObject*& OutOwner, FString& OutPropertyPath )	Returns full material property path and UObject owner property object Path examples: Material property path with array element and inner struct Materials[0].InnerStruct.Material Material property path with array element Materials[0] Simple material property path Materials
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.
UObject cons...	AdditionalStatObject()	Give a readable name for this component, including asset name if applicable
void	ApplyWorldOffset ( const FVector& InOffset, bool bWorldShift )	Called by owner actor on position shifting Component should update all relevant data structures to reflect new actor location
void	CheckForErrors()	Function that gets called from within Map_Check to allow this actor component to check itself for any potential errors and register them with map check dialog.
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	IsComponentTickEnabled()	Returns whether this component has tick enabled or not
bool	IsReadyForOwnerToAutoDestroy()	Overridable check for a component to indicate to its Owner that it should prevent the Actor from auto destroying when finished
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	SendRenderDynamicData_Concurrent()	Called to send dynamic data for this component to the rendering thread
void	SendRenderTransform_Concurrent()	Called to send a transform update for this component to the rendering thread
void	SetComponentTickEnabled ( bool bEnabled )	Set this component's tick functions to be enabled or disabled.
bool	ShouldActivate()	Return true if this component is in a state where it can be activated normally.
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	FinishDestroy()	Called to finish destroying the object.
FString	GetDetailedInfoInternal()	This function actually does the work for the GetDetailedInfo() and is virtual.
void	GetResourceSizeEx ( FResourceSizeEx& CumulativeResourc... )	Get the size of the object/resource for use in memory tools or to display to artists/LDs in the Editor This is the extended version which separates up the used memory into different memory regions (the actual definition of which may be platform specific).
void	PostEditChangeChainProperty ( FPropertyChangedChainEvent& Proper... )	This alternate version of PostEditChange is called when properties inside structs are modified.
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 ( FArchive& Ar )	Handles reading, writing, and reference collecting using FArchive.

Enums

	Name	Description
	EForceAsyncWorkCompletion

Typedefs

Name	Description
TrailEmitterArray	Array of trail emitters.

Constants

Name	Description
OnSystemPreActivationChange	Static delegate called for all systems on an activation change.

Deprecated Variables

		Name	Description
	TEnumAsByte< EA...	AutoAttachLocationType_DEPRECATED	DEPRECATED: Options for how we handle our location when we attach to the AutoAttachParent, if bAutoManageAttachment is true.