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  3. UNiagaraEmitter

UNiagaraEmitter

Niagara Emitters are particle spawners that can be reused for different effects by putting them into Niagara systems.

API > API/Plugins > API/Plugins/Niagara

Niagara Emitters are particle spawners that can be reused for different effects by putting them into Niagara systems. Emitters render their particles using different renderers, such as Sprite Renderers or Mesh Renderers to produce different effects.

Emitter assets cannot be spawned or used in a level directly, but need to be placed in a Niagara system. Emitters support inheritance, so that changes to the base asset are automatically picked up by child emitter assets and emitters in system assets.

   
Name UNiagaraEmitter
Type class
Header File /Engine/Plugins/FX/Niagara/Source/Niagara/Classes/NiagaraEmitter.h
Include Path #include "NiagaraEmitter.h"

Syntax

UCLASS (MinimalAPI)  
class UNiagaraEmitter :  
    public UNiagaraEmitterBase ,  
    public INiagaraParameterDefinitionsSubscriber ,  
    public FNiagaraVersionedObject

Inheritance Hierarchy

Implements Interfaces

Constructors

Name Remarks Include Path Unreal Specifiers

UNiagaraEmitter ( const FObjectInitializer& ObjectInitializer
)

   NiagaraEmitter.h  

Structs

Name Remarks
PrivateMemberNames  

Typedefs

Name Type Remarks Include Path
FOnEmitterCompiled TMulticastDelegate_OneParam< void, FVersionedNiagaraEmitter >   NiagaraEmitter.h
FOnEventHandlersChanged TMulticastDelegate_NoParams< void >   NiagaraEmitter.h
FOnPropertiesChanged TMulticastDelegate_NoParams< void >   NiagaraEmitter.h
FOnSimStagesChanged TMulticastDelegate_NoParams< void >   NiagaraEmitter.h

Constants

Name Type Remarks Include Path
EmitterMergeMessageId const FGuid   NiagaraEmitter.h

Variables

Public

Name Type Remarks Include Path Unreal Specifiers
bIsInheritable bool If an emitter is inheritable, new emitters based on an inheritable emitter, or Niagara Systems using an inheritable emitter, will automatically inherit changes made to the original emitter. NiagaraEmitter.h
  • EditAnywhere
  • Category="Asset Options"
  • AssetRegistrySearchable
Category FText Category to collate this emitter into for "add new emitter" dialogs. NiagaraEmitter.h
  • AssetRegistrySearchable
LibraryVisibility ENiagaraScriptLibraryVisibility The thumbnail image used for the asset. NiagaraEmitter.h
  • AssetRegistrySearchable
PreviewMoviePath FSoftObjectPath   NiagaraEmitter.h
  • EditAnywhere
  • AdvancedDisplay
  • Category="Asset Options"
  • AssetRegistrySearchable
  • Meta=(SkipSystemResetOnChange="true", AllowedClasses="/Script/MediaAssets.FileMediaSource")
TemplateAssetDescription FText   NiagaraEmitter.h
  • EditAnywhere
  • AdvancedDisplay
  • Category="Asset Options"
  • AssetRegistrySearchable
  • DisplayName="Asset Description"
VersionToOpenInEditor FGuid This is used as a transient value to open a specific version in the editor NiagaraEmitter.h
  • Transient

Protected

Name Type Remarks Include Path Unreal Specifiers
bFullyLoaded bool   NiagaraEmitter.h  
bVersioningEnabled bool If true then this emitter asset uses active version control to track changes. NiagaraEmitter.h  
ChangeId FGuid Adjusted every time that we compile this emitter. NiagaraEmitter.h  
ExposedVersion FGuid The exposed version is the version that is used by default when a user adds this emitter somewhere. NiagaraEmitter.h  
MessageStore FNiagaraMessageStore   NiagaraEmitter.h  
OnEventHandlersChangedDelegate FOnEventHandlersChanged   NiagaraEmitter.h  
OnGPUScriptCompiledDelegate FOnEmitterCompiled A multicast delegate which is called whenever all the scripts for this emitter have been compiled (successfully or not). NiagaraEmitter.h  
OnPropertiesChangedDelegate FOnPropertiesChanged   NiagaraEmitter.h  
OnSimStagesChangedDelegate FOnSimStagesChanged   NiagaraEmitter.h  
OnVMScriptCompiledDelegate FOnEmitterCompiled A multicast delegate which is called whenever all the scripts for this emitter have been compiled (successfully or not). NiagaraEmitter.h  
ParameterDefinitionsSubscriptions TArray< FParameterDefinitionsSubscription > Subscriptions to definitions of parameters. NiagaraEmitter.h  
VersionData TArray< FVersionedNiagaraEmitterData > Contains all of the versioned emitter data. NiagaraEmitter.h  

Functions

Public

Name Remarks Include Path Unreal Specifiers

void AddEventHandler ( FNiagaraEventScriptProperties EventHandler,
FGuid EmitterVersion
)

   NiagaraEmitter.h  

void AddRenderer ( UNiagaraRendererProperties* Renderer,
FGuid EmitterVersion
)

   NiagaraEmitter.h  

void AddSimulationStage ( UNiagaraSimulationStageBase* SimulationStage,
FGuid EmitterVersion
)

   NiagaraEmitter.h  

void ChangeParentVersion ( const FGuid& NewParentVersion,
const FGuid& EmitterVersion
)

   NiagaraEmitter.h  

void CheckVersionDataAvailable()

 Makes sure that the default version data is available and fixes old emitter assets. NiagaraEmitter.h  
Duplicates this emitter, but prevents the duplicate from merging in changes from the parent emitter. NiagaraEmitter.h  

void ForEachVersionData ( TAction Func
) const

   NiagaraEmitter.h  

void ForEachVersionData ( TAction Func
)

   NiagaraEmitter.h  

const TSharedPtr< FNiagaraGraphCachedDataBase, ESPMode::ThreadSafe > & GetCachedTraversalData ( const FGuid& EmitterVersion
) const

 Get the cached parameter map traversal for this emitter. NiagaraEmitter.h  

FGuid GetChangeId()

 Gets a Guid which is updated any time data in this emitter is changed. NiagaraEmitter.h  

const FVersionedNiagaraEmitterData * GetEmitterData ( const FGuid& VersionGuid
) const

   NiagaraEmitter.h  
Returns the emitter data for a specific version or nullptr if no such version is found. NiagaraEmitter.h  
  NiagaraEmitter.h  
Returns the emitter data for latest exposed version. NiagaraEmitter.h  

FNiagaraMessageStore & GetMessageStore()

   NiagaraEmitter.h  

TStatId GetStatID ( bool bGameThread,
bool bConcurrent
) const

   NiagaraEmitter.h  

void InvalidateCachedTraversalData ( const FGuid& EmitterVersion
)

   NiagaraEmitter.h  

bool IsEnabledOnPlatform ( const FString& PlatformName
) const

   NiagaraEmitter.h  

bool IsSynchronizedWithParent()

 Whether or not this emitter is synchronized with its parent emitter. NiagaraEmitter.h  
Merges in any changes from the parent emitter into this emitter. NiagaraEmitter.h  

void MoveRenderer ( UNiagaraRendererProperties* Renderer,
int32 NewIndex,
FGuid EmitterVersion
)

   NiagaraEmitter.h  

void MoveSimulationStageToIndex ( UNiagaraSimulationStageBase* SimulationStage,
int32 TargetIndex,
FGuid EmitterVersion
)

   NiagaraEmitter.h  

virtual bool NeedsLoadForTargetPlatform ( const ITargetPlatform* TargetPlatform
) const

   NiagaraEmitter.h  

void NotifyScratchPadScriptsChanged()

   NiagaraEmitter.h  

FOnEmitterCompiled & OnEmitterGPUCompiled()

 Callback issued whenever a VM compilation successfully happened (even if the results are a script that cannot be executed due to errors) NiagaraEmitter.h  

FOnEmitterCompiled & OnEmitterVMCompiled()

 Callback issued whenever a VM compilation successfully happened (even if the results are a script that cannot be executed due to errors) NiagaraEmitter.h  

FOnSimStagesChanged & OnEventHandlersChanged()

   NiagaraEmitter.h  

FOnEmitterCompiled & OnGPUCompilationComplete()

 Callback issued whenever a GPU compilation successfully happened (even if the results are a script that cannot be executed due to errors) NiagaraEmitter.h  

void OnPostCompile ( const FGuid& EmitterVersion
)

   NiagaraEmitter.h  

FOnPropertiesChanged & OnPropertiesChanged()

   NiagaraEmitter.h  

FOnSimStagesChanged & OnSimStagesChanged()

   NiagaraEmitter.h  

virtual void PostEditChangeVersionedProperty ( FPropertyChangedEvent& PropertyChangedEvent,
const FGuid& Version
)

   NiagaraEmitter.h  

void RebindNotifications()

 Helper method for binding the notifications needed for proper editor integration. NiagaraEmitter.h  

void RemoveEventHandlerByUsageId ( FGuid EventHandlerUsageId,
FGuid EmitterVersion
)

   NiagaraEmitter.h  

void RemoveRenderer ( UNiagaraRendererProperties* Renderer,
FGuid EmitterVersion
)

   NiagaraEmitter.h  

void RemoveSimulationStage ( UNiagaraSimulationStageBase* SimulationStage,
FGuid EmitterVersion
)

   NiagaraEmitter.h  

void SetEditorData ( UNiagaraEditorDataBase* InEditorData,
const FGuid& VersionGuid
)

   NiagaraEmitter.h  

void SetParent ( const FVersionedNiagaraEmitter& InParent
)

   NiagaraEmitter.h  

void UpdateEmitterAfterLoad()

   NiagaraEmitter.h  

void UpdateScalability()

   NiagaraEmitter.h  

void UpdateStatID()

   NiagaraEmitter.h  

Overridden from UNiagaraEmitterBase

Name Remarks Include Path Unreal Specifiers

virtual bool CanObtainEmitterAttribute ( const FNiagaraVariableBase& InVarWithUniqueNameNamespace,
FNiagaraTypeDefinition& OutBoundType
) const

   NiagaraEmitter.h  

virtual bool CanObtainParticleAttribute ( const FNiagaraVariableBase& InVar,
const FGuid& EmitterVersion,
FNiagaraTypeDefinition& OutBoundType
) const

   NiagaraEmitter.h  

virtual FNiagaraVariableBase GetResolvedDIBinding ( const FNiagaraVariableBase& InVariable
) const

   NiagaraEmitter.h  

virtual void HandleVariableRemoved ( const FNiagaraVariable& InOldVariable,
bool bUpdateContexts,
FGuid EmitterVersion
)

   NiagaraEmitter.h  

virtual void HandleVariableRenamed ( const FNiagaraVariable& InOldVariable,
const FNiagaraVariable& InNewVariable,
bool bUpdateContexts,
FGuid EmitterVersion
)

   NiagaraEmitter.h  

Overridden from UObject

Name Remarks Include Path Unreal Specifiers

virtual void GetAssetRegistryTags ( TArray< FAssetRegistryTag >& OutTags
) const

   NiagaraEmitter.h  

virtual void GetAssetRegistryTags ( FAssetRegistryTagsContext Context
) const

   NiagaraEmitter.h  

virtual bool IsEditorOnly()

   NiagaraEmitter.h  

virtual void PostDuplicate ( EDuplicateMode::Type DuplicateMode
)

   NiagaraEmitter.h  

virtual void PostEditChangeProperty ( FPropertyChangedEvent& PropertyChangedEvent
)

   NiagaraEmitter.h  

virtual void PostInitProperties()

   NiagaraEmitter.h  

virtual void PostLoad()

   NiagaraEmitter.h  

virtual void PostRename ( UObject* OldOuter,
const FName OldName
)

   NiagaraEmitter.h  

virtual PRAGMA_DISABLE_DEPRECATION_WARNINGS void PreSave ( FObjectPreSaveContext ObjectSaveContext
)

   NiagaraEmitter.h  

virtual void Serialize ( FArchive& Ar
)

   NiagaraEmitter.h  

Overridden from INiagaraParameterDefinitionsSubscriber

Name Remarks Include Path Unreal Specifiers

virtual TArray< UNiagaraScriptSourceBase * > GetAllSourceScripts()

 Get all UNiagaraScriptSourceBase of this subscriber. NiagaraEmitter.h  

virtual TArray< UNiagaraEditorParametersAdapterBase * > GetEditorOnlyParametersAdapters()

 Get All adapters to editor only script vars owned directly by this subscriber. NiagaraEmitter.h  
  NiagaraEmitter.h  
  NiagaraEmitter.h  

virtual FString GetSourceObjectPathName()

 Get the path to the UObject of this subscriber. NiagaraEmitter.h  

Overridden from FNiagaraVersionedObject

Name Remarks Include Path Unreal Specifiers

virtual FGuid AddNewVersion ( int32 MajorVersion,
int32 MinorVersion
)

 Creates a new data entry for the given version number. NiagaraEmitter.h  

virtual void DeleteVersion ( const FGuid& VersionGuid
)

 Deletes the version data for an existing version. NiagaraEmitter.h  

virtual void DisableVersioning ( const FGuid& VersionGuidToUse
)

 Disables versioning and keeps only the data from the given version guid. NiagaraEmitter.h  

virtual void EnableVersioning()

 Enables versioning for this emitter asset. NiagaraEmitter.h  

virtual void ExposeVersion ( const FGuid& VersionGuid
)

 Changes the exposed version. Does nothing if the guid does not exist in the version data. NiagaraEmitter.h  

virtual FNiagaraAssetVersion const * FindVersionData ( const FGuid& VersionGuid
) const

 Returns the version data for the given guid, if it exists. Otherwise returns nullptr. NiagaraEmitter.h  

virtual TArray< FNiagaraAssetVersion > GetAllAvailableVersions()

 Returns all available versions for this emitter. NiagaraEmitter.h  

virtual FNiagaraAssetVersion GetExposedVersion()

 Returns the version of the exposed version data (i.e. the version used when adding an emitter to a system) NiagaraEmitter.h  

virtual TSharedPtr< FNiagaraVersionDataAccessor > GetVersionDataAccessor ( const FGuid& Version
)

   NiagaraEmitter.h  

virtual bool IsVersioningEnabled()

 If true then this script asset uses active version control to track changes. NiagaraEmitter.h  

Protected

Overridden from UNiagaraEmitterBase

Name Remarks Include Path Unreal Specifiers

virtual void OnUniqueEmitterNameChanged ( const FString& OldName
)

 Called if the emitter name was successfully changed. NiagaraEmitter.h  

Overridden from UObject

Name Remarks Include Path Unreal Specifiers

virtual void BeginDestroy()

   NiagaraEmitter.h  

Static

Name Remarks Include Path Unreal Specifiers

static UNiagaraEmitter * CreateAsDuplicate ( const UNiagaraEmitter& InEmitterToDuplicate,
FName InDuplicateName,
UNiagaraSystem& InDuplicateOwnerSystem
)

 Creates a new emitter by duplicating an existing emitter. NiagaraEmitter.h  

static UNiagaraEmitter * CreateWithParentAndOwner ( FVersionedNiagaraEmitter 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. NiagaraEmitter.h  

static void DeclareConstructClasses ( TArray< FTopLevelAssetPath >& OutConstructClasses,
const UClass* SpecificSubclass
)

   NiagaraEmitter.h  

static bool GetForceCompileOnLoad()

   NiagaraEmitter.h  

Deprecated Variables

Name Type Remarks Include Path Unreal Specifiers
AllocationMode_DEPRECATED EParticleAllocationMode Use property in struct returned from GetEmitterData() instead NiagaraEmitter.h
  • Meta=(DeprecatedProperty)
AssetTags_DEPRECATED TArray< FNiagaraAssetTagDefinitionReference >   NiagaraEmitter.h
  • Meta=(DeprecatedProperty)
AttributesToPreserve_DEPRECATED TArray< FString > Use property in struct returned from GetEmitterData() instead NiagaraEmitter.h
  • Meta=(DeprecatedProperty)
bDeterminism_DEPRECATED bool Use property in struct returned from GetEmitterData() instead NiagaraEmitter.h
  • Meta=(DeprecatedProperty)
bExposeToLibrary_DEPRECATED bool Deprecated library exposure bool. NiagaraEmitter.h  
bFixedBounds_DEPRECATED uint32 Use property in struct returned from GetEmitterData() instead NiagaraEmitter.h
  • Meta=(DeprecatedProperty, ScriptNoExport)
bInterpolatedSpawning_DEPRECATED uint32 Use property in struct returned from GetEmitterData() instead NiagaraEmitter.h
  • Meta=(DeprecatedProperty)
bIsTemplateAsset_DEPRECATED bool Deprecated template asset bool. Use the TemplateSpecification enum instead. NiagaraEmitter.h  
bLocalSpace_DEPRECATED bool --------------- Most properties below this point are deprecated and stored in the versioned emitter data instead! --------------------------------------------------------------------------------------------- NiagaraEmitter.h
  • Meta=(DeprecatedProperty)
bOverrideGlobalSpawnCountScale_DEPRECATED uint32 Legacy bool to control overriding the global spawn count scales. NiagaraEmitter.h  
bRequiresPersistentIDs_DEPRECATED uint32 Use property in struct returned from GetEmitterData() instead NiagaraEmitter.h
  • Meta=(DeprecatedProperty)
bUseMaxDetailLevel_DEPRECATED uint32 Whether to use the min detail or not. NiagaraEmitter.h  
bUseMinDetailLevel_DEPRECATED uint32 Whether to use the min detail or not. NiagaraEmitter.h  
EmitterSpawnScriptProps_DEPRECATED FNiagaraEmitterScriptProperties Use property in struct returned from GetEmitterData() instead NiagaraEmitter.h
  • Meta=(DeprecatedProperty)
EmitterUpdateScriptProps_DEPRECATED FNiagaraEmitterScriptProperties Use property in struct returned from GetEmitterData() instead NiagaraEmitter.h
  • Meta=(DeprecatedProperty)
FixedBounds_DEPRECATED FBox Use property in struct returned from GetEmitterData() instead NiagaraEmitter.h
  • Meta=(DeprecatedProperty, ScriptNoExport)
GlobalSpawnCountScaleOverrides_DEPRECATED FNiagaraDetailsLevelScaleOverrides   NiagaraEmitter.h  
GraphSource_DEPRECATED TObjectPtr< UNiagaraScriptSourceBase > Use property in struct returned from GetEmitterData() instead NiagaraEmitter.h
  • Meta=(DeprecatedProperty)
MaxDetailLevel_DEPRECATED int32   NiagaraEmitter.h  
MaxGPUParticlesSpawnPerFrame_DEPRECATED uint32 Use property in struct returned from GetEmitterData() instead NiagaraEmitter.h
  • Meta=(DeprecatedProperty)
MinDetailLevel_DEPRECATED int32   NiagaraEmitter.h  
ParentScratchPadScripts_DEPRECATED TArray< TObjectPtr< UNiagaraScript > > Use property in struct returned from GetEmitterData() instead NiagaraEmitter.h
  • Meta=(DeprecatedProperty)
Platforms_DEPRECATED FNiagaraPlatformSet Use property in struct returned from GetEmitterData() instead NiagaraEmitter.h
  • Meta=(DeprecatedProperty)
PreAllocationCount_DEPRECATED int32 Use property in struct returned from GetEmitterData() instead NiagaraEmitter.h
  • Meta=(DeprecatedProperty)
RandomSeed_DEPRECATED int32 Use property in struct returned from GetEmitterData() instead NiagaraEmitter.h
  • Meta=(DeprecatedProperty)
RendererBindings_DEPRECATED FNiagaraParameterStore   NiagaraEmitter.h
  • Meta=(DeprecatedProperty)
ScalabilityOverrides_DEPRECATED FNiagaraEmitterScalabilityOverrides Use property in struct returned from GetEmitterData() instead NiagaraEmitter.h
  • Meta=(DeprecatedProperty)
ScratchPadScripts_DEPRECATED TArray< TObjectPtr< UNiagaraScript > > Use property in struct returned from GetEmitterData() instead NiagaraEmitter.h
  • Meta=(DeprecatedProperty)
SimTarget_DEPRECATED ENiagaraSimTarget Use property in struct returned from GetEmitterData() instead NiagaraEmitter.h
  • Meta=(DeprecatedProperty)
SpawnScriptProps_DEPRECATED FNiagaraEmitterScriptProperties Use property in struct returned from GetEmitterData() instead NiagaraEmitter.h
  • Meta=(DeprecatedProperty)
TemplateSpecification_DEPRECATED ENiagaraScriptTemplateSpecification   NiagaraEmitter.h
  • Meta=(DeprecatedProperty)
UpdateScriptProps_DEPRECATED FNiagaraEmitterScriptProperties Use property in struct returned from GetEmitterData() instead NiagaraEmitter.h
  • Meta=(DeprecatedProperty)

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