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> Unreal Engine API Reference > Plugins > Niagara > UNiagaraEmitter

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UNiagaraEmitter

[UNiagaraEmitter](API\Plugins\Niagara\UNiagaraEmitter) stores the attributes of an [FNiagaraEmitterInstance](API\Plugins\Niagara\FNiagaraEmitterInstance) that need to be serialized and are used for its initialization

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MacOS

Linux

Inheritance Hierarchy

UObjectBase

UObjectBaseUtility

UObject

UNiagaraEmitter

References

Module	Niagara
Header	/Engine/Plugins/FX/Niagara/Source/Niagara/Classes/NiagaraEmitter.h
Include	#include "NiagaraEmitter.h"

Syntax

[UCLASS](Programming/UnrealArchitecture/Reference/Classes#classdeclaration)(MinimalAPI)
class UNiagaraEmitter :
public UObject,
public INiagaraParameterDefinitionsSubscriber

Remarks

UNiagaraEmitter stores the attributes of an FNiagaraEmitterInstance that need to be serialized and are used for its initialization

Variables

	Name	Description
EParticleAlloca...	AllocationMode	The emitter needs to allocate memory for the particles each tick.
TArray< FString...	AttributesToPreserve	A whitelist of Particle attributes (e.g. "Particle.Position" or "Particle.Age") that will not be removed from the DataSet even if they aren't read by the VM.
uint32: 1	bBakeOutRapidIteration	Should we enable rapid iteration removal if the system is also set to remove rapid iteration parameters on compile? This value defaults to true.
uint32: 1	bCombineEventSpawn	Performance option to allow event based spawning to be combined into a single spawn.
uint32: 1	bDeprecatedShaderStagesEnabled	Get whether or not to use shader stages.
bool	bDeterminism	Toggles whether to globally make the random number generator be deterministic or non-deterministic.
bool	bExposeToLibrary	If this emitter is exposed to the library.
uint32: 1	bFixedBounds	Whether or not fixed bounds are enabled.
uint32: 1	bInterpolatedSpawning	When enabled, this will spawn using interpolated parameter values and perform a partial update at spawn time.
uint32: 1	bLimitDeltaTime	Whether to limit the max tick delta time or not.
bool	bLocalSpace	Toggles whether or not the particles within this emitter are relative to the emitter origin or in global space.
uint32: 1	bRequiresPersistentIDs	Do particles in this emitter require a persistent ID?
uint32: 1	bSimulationStagesEnabled	Get whether or not to use simulation stages.
FText	Category	Category to collate this emitter into for "add new emitter" dialogs.
uint32	DefaultShaderStageIndex	Get the default shader stage index.
FNiagaraEmitter...	EmitterSpawnScriptProps
FNiagaraEmitter...	EmitterUpdateScriptProps
FBox	FixedBounds	The fixed bounding box value. bFixedBounds is the condition whether the fixed bounds can be edited.
UNiagaraScriptS...	GraphSource	'Source' data/graphs for the scripts used by this emitter.
float	MaxDeltaTimePerTick	Limits the delta time per tick to prevent simulation spikes due to frame lags.
uint32	MaxUpdateIterations	Get the number of shader stages that we fire off.
TArray< UNiagar...	ParentScratchPadScripts
FNiagaraPlatfor...	Platforms
int32	PreAllocationCount	The emitter will allocate at least this many particles on it's first tick.
int32	RandomSeed	An emitter-based seed for the deterministic random number generator.
FNiagaraEmitter...	ScalabilityOverrides
TArray< UNiagar...	ScratchPadScripts
ENiagaraSimTarg...	SimTarget
FNiagaraEmitter...	SpawnScriptProps
TSet< uint32 >	SpawnStages	Get whether or not shaderstages spwn.
FText	TemplateAssetDescription
ENiagaraScriptT...	TemplateSpecification
UTexture2D *...	ThumbnailImage	Internal: The thumbnail image.
uint32: 1	ThumbnailImageOutOfDate	Internal: Indicates the thumbnail image is out of date.
FNiagaraEmitter...	UpdateScriptProps

Constructors

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

Functions

	Name	Description
void	AddEventHandler ( FNiagaraEventScriptProperties Event... )
void	AddMessage ( const FGuid& MessageKey, UNiagaraMessageDataBase* NewMe... )
void	AddRenderer ( UNiagaraRendererProperties* Re... )
int32	AddRuntimeAllocation ( uint64 ReporterHandle, int32 AllocationCount )	This is used by the emitter instances to report runtime allocations to reduce reallocation in future simulation runs.
void	AddSimulationStage ( UNiagaraSimulationStageBase* S... )
bool	AreAllScriptAndSourcesSynchronized()
void	BindNotifications()	Helper method for binding the notifications needed for proper editor integration.
void	CacheFromCompiledData ( const FNiagaraDataSetCompiledData&... )
void	CacheFromShaderCompiled()
bool	CanObtainEmitterAttribute ( const FNiagaraVariableBase& InVarW... )
bool	CanObtainParticleAttribute ( const FNiagaraVariableBase& InVar )
bool	CanObtainSystemAttribute ( const FNiagaraVariableBase& InVar )
bool	CanObtainUserVariable ( const FNiagaraVariableBase& InVar )
void	ClearRuntimeAllocationEstimate ( uint64 ReportHandle )
UNiagaraEmit...	CreateAsDuplicate ( const UNiagaraEmitter& InEmitterTo..., FName InDuplicateName, UNiagaraSystem& InDuplicateOwnerSy... )	Creates a new emitter by duplicating an existing emitter.
UNiagaraEmit...	CreateWithParentAndOwner ( UNiagaraEmitter& InParentEmitter, UObject* InOwner, FName InName, EObjectFlags FlagMask )	Creates a new emitter with the supplied emitter as a parent emitter and the supplied system as its owner.
UNiagaraEmit...	DuplicateWithoutMerging ( UObject* InOuter )	Duplicates this emitter, but prevents the duplicate from merging in changes from the parent emitter.
void	ForEachEnabledRenderer ( TAction Func )
void	ForEachScript ( TAction Func )
TConstArrayV...	GetBoundsCalculators()
FGuid	GetChangeId()	Gets a Guid which is updated any time data in this emitter is changed.
const TCHAR ...	GetDebugSimName()
UNiagaraEdit...	GetEditorData()
UNiagaraEdit...	GetEditorParameters()
FNiagaraEven...	GetEventHandlerByIdUnsafe ( FGuid ScriptUsageId )	Gets a pointer to an event handler by script usage id.
const TArray...	GetEventHandlers()
bool	GetForceCompileOnLoad()
const UNiaga...	GetGPUComputeScript()
UNiagaraScri...	GetGPUComputeScript()
uint32	GetMaxInstanceCount()
int32	GetMaxParticleCountEstimate()	Returns the number of max expected particles for memory allocations.
const TMap< ...	GetMessages()
UNiagaraEmit...	GetParent()
UNiagaraEmit...	GetParentAtLastMerge()
const TArray...	GetRenderers()
const FNiaga...	GetScalabilitySettings()
UNiagaraScri...	GetScript ( ENiagaraScriptUsage Usage, FGuid UsageId )
void	GetScripts ( TArray< UNiagaraScript* >& Ou..., bool bCompilableOnly, bool bEnabledOnly )
UNiagaraSimu...	GetSimulationStageById ( FGuid ScriptUsageId )
const TArray...	GetSimulationStages()
TStatId	GetStatID ( bool bGameThread, bool bConcurrent )
FString	GetUniqueEmitterName()
void	HandleVariableRemoved ( const FNiagaraVariable& InOldVaria..., bool bUpdateContexts )	Helper method for when a rename has been detected within the graph.
void	HandleVariableRenamed ( const FNiagaraVariable& InOldVaria..., const FNiagaraVariable& InNewVaria..., bool bUpdateContexts )	Helper method for when a rename has been detected within the graph.
void	InvalidateCompileResults()
bool	IsAllowedByScalability()	Returns true if this emitter's platform filter allows it on this platform and quality level.
bool	IsEnabledOnPlatform ( const FString& PlatformName )
bool	IsEventGeneratorShared ( FName EventGeneratorId )	Gets whether or not the supplied event generator id matches an event generator which is shared between the particle spawn and update scrips.
bool	IsReadyToRun()
bool	IsSynchronizedWithParent()	Whether or not this emitter is synchronized with its parent emitter.
bool	IsValid()
INiagaraMerg...	MergeChangesFromParent()	Merges in any changes from the parent emitter into this emitter.
void	MoveSimulationStageToIndex ( UNiagaraSimulationStageBase* S..., int32 TargetIndex )
bool	NeedsLoadForTargetPlatform ( const ITargetPlatform* TargetP... )
void	NotifyScratchPadScriptsChanged()
FOnEmitterCo...	OnEmitterGPUCompiled()	Callback issued whenever a VM compilation successfully happened (even if the results are a script that cannot be executed due to errors)
FOnEmitterCo...	OnEmitterVMCompiled()	Callback issued whenever a VM compilation successfully happened (even if the results are a script that cannot be executed due to errors)
FOnEmitterCo...	OnGPUCompilationComplete()	Callback issued whenever a GPU compilation successfully happened (even if the results are a script that cannot be executed due to errors)
void	OnPostCompile()
FOnPropertie...	OnPropertiesChanged()
FOnRenderers...	OnRenderersChanged()
void	OnScalabilityCVarChanged()
void	RemoveEventHandlerByUsageId ( FGuid EventHandlerUsageId )
void	RemoveMessage ( const FGuid& MessageKey )
void	RemoveMessageDelegateable ( const FGuid MessageKey )
void	RemoveParent()
void	RemoveRenderer ( UNiagaraRendererProperties* Re... )
void	RemoveSimulationStage ( UNiagaraSimulationStageBase* S... )
NIAGARA_API ...	Reparent ( UNiagaraEmitter& InParent )
bool	RequiresPersistentIDs()
bool	RequiresViewUniformBuffer()
void	ResolveScalabilitySettings()
void	SetEditorData ( UNiagaraEditorDataBase* InEdit... )
void	SetParent ( UNiagaraEmitter& InParent )
bool	SetUniqueEmitterName ( const FString& InName )
void	UpdateEmitterAfterLoad()
bool	UsesCollection ( const UNiagaraParameterCollection&... )	Bool UsesDataInterface(UNiagaraDataInterface* Interface);
bool	UsesEmitter ( const UNiagaraEmitter& InEmitter )	Whether or not this emitter uses the supplied emitter
bool	UsesScript ( const UNiagaraScript* Script )

Overridden from UObject

	Name	Description
void	BeginDestroy()	Called before destroying the object.
void	GetAssetRegistryTags ( TArray< FAssetRegistryTag >& OutTa... )	Gathers a list of asset registry searchable tags which are name/value pairs with some type information This only needs to be implemented for asset objects
bool	IsEditorOnly()	Called during saving to determine if the object is forced to be editor only or not
void	PostDuplicate ( EDuplicateMode::Type DuplicateMode )
void	PostEditChangeProperty ( FPropertyChangedEvent& PropertyCha... )	Called when a property on this object has been modified externally
void	PostInitProperties()	Called after the C++ constructor and after the properties have been initialized, including those loaded from config.
void	PostLoad()	Do any object-specific cleanup required immediately after loading an object.
void	PostRename ( UObject* OldOuter, const FName OldName )	Called at the end of Rename(), but only if the rename was actually carried out
void	PreSave ( const ITargetPlatform* TargetP... )	Presave function.
void	Serialize ( FArchive& Ar )	Handles reading, writing, and reference collecting using FArchive.

Overridden from INiagaraParameterDefinitionsSubscriber

	Name	Description
TArray< UNia...	GetAllSourceScripts()	Get all UNiagaraScriptSourceBase of this subscriber.
TArray< UNia...	GetEditorOnlyParametersAdapters()	Get All adapters to editor only script vars owned directly by this subscriber.
const TArray...	GetParameterDefinitionsSubscriptions()
TArray< FPar...	GetParameterDefinitionsSubscriptions()
FString	GetSourceObjectPathName()	Get the path to the UObject of this subscriber.

Classes

	Name	Description
	PrivateMemberNames

Typedefs

Name	Description
FOnEmitterCompiled
FOnPropertiesChanged
FOnRenderersChanged

Deprecated Variables

	Name	Description
bool	bIsTemplateAsset_DEPRECATED
uint32: 1	bOverrideGlobalSpawnCountScale_DEPRECATED	Legacy bool to control overriding the global spawn count scales.
uint32: 1	bUseMaxDetailLevel_DEPRECATED	Whether to use the min detail or not.
uint32: 1	bUseMinDetailLevel_DEPRECATED	Whether to use the min detail or not.
FNiagaraDetails...	GlobalSpawnCountScaleOverrides_DEPRECATED
int32	MaxDetailLevel_DEPRECATED
int32	MinDetailLevel_DEPRECATED

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