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> Unreal Engine API Reference > Plugins > Niagara > UNiagaraScript

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UNiagaraScript

Runtime script for a Niagara system

Inheritance Hierarchy

UObjectBase

UObjectBaseUtility

UObject

UNiagaraScriptBase

UNiagaraScript

References

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

Syntax

UCLASS(MinimalAPI)
class UNiagaraScript :
public UNiagaraScriptBase,
public FNiagaraVersionedObject

Remarks

Runtime script for a Niagara system

Variables

	Name	Description
FNiagaraParamet...	RapidIterationParameters	Contains all of the top-level values that are iterated on in the UI.
FNiagaraParamet...	RapidIterationParametersCookedEditorCache
ENiagaraScriptU...	Usage	How this script is to be used. cannot be private due to use of GET_MEMBER_NAME_CHECKED
TArray< TObject...	ValidationRules	A set of rules to apply when this script is used in the stack.
FGuid	VersionToOpenInEditor	This is used as a transient value to open a specific version in the graph editor

Constructors

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

Functions

	Name	Description
FNiagaraShad...	AllocateResource()
bool	AreScriptAndSourceSynchronized ( const FGuid& VersionGuid )	Determine if the Script and its source graph are in sync.
bool	BinaryToExecData ( const UNiagaraScript* Script, const TArray< uint8 >& InBinaryDat..., FNiagaraVMExecutableData& OutExecD... )	Helper to convert the struct from its binary data out of the DDC to it's actual in-memory version.
FString	BuildNiagaraDDCKeyString ( const FNiagaraVMExecutableDataId& ..., const FString& ScriptPath )	Builds the DDC string for the derived data cache using the supplied CompiledId and ScriptPath
void	CacheResourceShadersForCooking ( EShaderPlatform ShaderPlatform, TArray< FNiagaraShaderScript* ..., const ITargetPlatform* TargetP... )	Infrastructure for GPU compute Shaders.
void	CacheResourceShadersForRendering ( bool bRegenerateId, bool bForceRecompile )
void	CacheShadersForResources ( FNiagaraShaderScript* Resource..., bool bApplyCompletedShaderMapForRen..., bool bForceRecompile, bool bCooking, const ITargetPlatform* TargetP... )
bool	CanBeRunOnGpu()
void	CheckVersionDataAvailable()	Makes sure that the default version data is available and fixes old script assets.
void	ComputeVMCompilationId ( FNiagaraVMExecutableDataId& Id, FGuid VersionGuid )
bool	ContainsEquivilentUsage ( const TArray< ENiagaraScriptUsage >..., ENiagaraScriptUsage InUsage )
bool	ContainsUsage ( ENiagaraScriptUsage InUsage )
bool	ConvertUsageToGroup ( ENiagaraScriptUsage InUsage, ENiagaraScriptGroup& OutGroup )
UNiagaraScri...	CreateCompilationCopy()	Creates a shallow transient copy of this script for compilation purposes.
bool	DidScriptCompilationSucceed ( bool bGPUScript )
bool	ExecToBinaryData ( const UNiagaraScript* Script, TArray< uint8 >& OutBinaryData, FNiagaraVMExecutableData& InExecDa... )	Reverse of the BinaryToExecData() function
TArray< FNam...	FindShaderFormatsForCooking ( const ITargetPlatform* TargetP... )
void	GenerateStatIDs()
FGuid	GetBaseChangeID ( const FGuid& VersionGuid )
TConstArrayV...	GetCachedDefaultDataInterfaces()
TArray< FNia...	GetCachedDefaultDataInterfaces()
TArray< UNia...	GetCachedParameterCollectionReferences()
TOptional< F...	GetCompilerTag ( const FNiagaraVariableBase& InVar, const FNiagaraParameterStore* ... )
TOptional< T...	GetCompilerTag ( const FNiagaraVariableBase& InVar, const FNiagaraParameterStore* ... )
const FNiaga...	GetComputedVMCompilationId()
TConstArrayV...	GetDataInterfaceGPUParamInfos()
FText	GetDescription ( const FGuid& VersionGuid )
const FNiaga...	GetExecutionReadyParameterStore ( ENiagaraSimTarget SimTarget )
FString	GetFriendlyName()
ENiagaraScri...	GetLastCompileStatus()
const FVersi...	GetLatestScriptData()	Returns the script data for latest exposed version.
FVersionedNi...	GetLatestScriptData()	Returns the script data for latest exposed version.
UNiagaraScri...	GetLatestSource()
const UNiaga...	GetLatestSource()
FString	GetNiagaraDDCKeyString ( const FGuid& ScriptVersion, const FString& ScriptPath )	Creates a string key for the derived data cache
FVersionedNi...	GetOuterEmitter()	Workaround for emitter versioning because we used a lot of Script->GetOuter() previously.
FNiagaraShad...	GetRenderThreadScript()
const FNiaga...	GetRenderThreadScript()
FVersionedNi...	GetScriptData ( const FGuid& VersionGuid )	Returns the script data for a specific version or nullptr if no such version is found.
const FVersi...	GetScriptData ( const FGuid& VersionGuid )	Returns the script data for a specific version or nullptr if no such version is found.
const UNiaga...	GetSource ( const FGuid& VersionGuid )
UNiagaraScri...	GetSource ( const FGuid& VersionGuid )
TArray< ENia...	GetSupportedUsageContextsForBitmask ( int32 InModuleUsageBitmask, bool bIncludeHiddenUsages )
ENiagaraScri...	GetUsage()
FGuid	GetUsageId()
FNiagaraVMEx...	GetVMExecutableData()
const FNiaga...	GetVMExecutableData()
const FNiaga...	GetVMExecutableDataCompilationId()
FGraphEventR...	HandleByteCodeOptimization ( bool bShouldForceNow )	Kicks off an async job to convert the ByteCode into an optimized version for the platform we are running on.
bool	HandleVariableRenames ( const TMap< FNiagaraVariable, FNiag..., const FString& UniqueEmitterName )
void	InvalidateCompileResults ( const FString& Reason )
void	InvalidateExecutionReadyParameterStores()
bool	IsCompilable()
bool	IsCompilable ( ENiagaraScriptUsage Usage )
bool	IsDynamicInputScript ( ENiagaraScriptUsage Usage )
bool	IsDynamicInputScript()
bool	IsEmitterScript ( ENiagaraScriptUsage Usage )
bool	IsEmitterSpawnScript ( ENiagaraScriptUsage Usage )
bool	IsEmitterSpawnScript()
bool	IsEmitterUpdateScript()
bool	IsEmitterUpdateScript ( ENiagaraScriptUsage Usage )
bool	IsEquivalentUsage ( ENiagaraScriptUsage InUsage )
bool	IsEquivalentUsage ( ENiagaraScriptUsage InUsageA, ENiagaraScriptUsage InUsageB )
bool	IsFunctionScript()
bool	IsFunctionScript ( ENiagaraScriptUsage Usage )
bool	IsGPUScript ( ENiagaraScriptUsage Usage )
bool	IsInterpolatedParticleSpawnScript ( ENiagaraScriptUsage Usage )
bool	IsInterpolatedParticleSpawnScript()
bool	IsModuleScript()
bool	IsModuleScript ( ENiagaraScriptUsage Usage )
bool	IsNonParticleScript()
bool	IsNonParticleScript ( ENiagaraScriptUsage Usage )
bool	IsParticleEventScript()
bool	IsParticleEventScript ( ENiagaraScriptUsage Usage )
bool	IsParticleScript()
bool	IsParticleScript ( ENiagaraScriptUsage Usage )
bool	IsParticleSpawnScript()
bool	IsParticleSpawnScript ( ENiagaraScriptUsage Usage )
bool	IsParticleStageScript ( ENiagaraScriptUsage Usage )
bool	IsParticleUpdateScript()
bool	IsParticleUpdateScript ( ENiagaraScriptUsage Usage )
bool	IsReadyToRun ( ENiagaraSimTarget SimTarget )
bool	IsScriptCompilationPending ( bool bGPUScript )
bool	IsScriptCooked()
bool	IsSpawnScript ( ENiagaraScriptUsage Usage )
bool	IsSpawnScript()
bool	IsStandaloneScript()
bool	IsStandaloneScript ( ENiagaraScriptUsage Usage )
bool	IsSupportedUsageContextForBitmask ( int32 InModuleUsageBitmask, ENiagaraScriptUsage InUsageContext, bool bIncludeHiddenUsages )
bool	IsSystemScript ( ENiagaraScriptUsage Usage )
bool	IsSystemSpawnScript ( ENiagaraScriptUsage Usage )
bool	IsSystemSpawnScript()
bool	IsSystemUpdateScript ( ENiagaraScriptUsage Usage )
bool	IsSystemUpdateScript()
bool	IsUsageDependentOn ( ENiagaraScriptUsage InUsageA, ENiagaraScriptUsage InUsageB )	Is usage A dependent on Usage B?
void	MarkScriptAndSourceDesynchronized ( FString Reason, const FGuid& VersionGuid )	Ensure that the Script and its source graph are marked out of sync.
FOnScriptCom...	OnGPUScriptCompiled()	Callback issued whenever a GPU script compilation successfully happened (even if the results are a script that cannot be executed due to errors)
FOnPropertyC...	OnPropertyChanged()	Callback issues whenever post edit changed is called on this script.
FOnScriptCom...	OnVMScriptCompiled()	Callback issued whenever a VM script compilation successfully happened (even if the results are a script that cannot be executed due to errors)
void	PostEditChangeVersionedProperty ( FPropertyChangedEvent& PropertyCha..., const FGuid& Version )
void	RaiseOnGPUCompilationComplete()
void	RequestCompile ( const FGuid& ScriptVersion, bool bForceCompile )	Request a synchronous compile for the script, possibly forcing it to compile.
bool	RequestExternallyManagedAsyncCompile ( const TSharedPtr< FNiagaraCompileRe..., const TSharedPtr< FNiagaraCompileRe..., FNiagaraVMExecutableDataId& OutCom..., uint32& OutAsyncHandle )	Request an asynchronous compile for the script, possibly forcing it to compile.
void	SaveShaderStableKeys ( const ITargetPlatform* TP )
void	SetLatestSource ( UNiagaraScriptSourceBase* InSo... )
void	SetPreviewFeatureLevel ( ERHIFeatureLevel::Type PreviewFeatu... )
void	SetSource ( UNiagaraScriptSourceBase* InSo..., const FGuid& VersionGuid )
void	SetUsage ( ENiagaraScriptUsage InUsage )
void	SetUsageId ( const FGuid& InUsageId )
void	SetVMCompilationResults ( const FNiagaraVMExecutableDataId& ..., FNiagaraVMExecutableData& InScript..., FString EmitterUniqueName, const TMap< FName, UNiagaraDataInte..., bool ApplyRapidIterationParameters )	External call used to identify the values for a successful VM script compilation.
void	SyncAliases ( const FNiagaraAliasContext& Resolv... )
bool	SynchronizeExecutablesWithCompilation ( const UNiagaraScript* Script, const TMap< FString, FString >& Re... )	In the event where we "merge" we duplicate the changes of the source script onto the newly cloned copy.
bool	UsesCollection ( const UNiagaraParameterCollection&... )

Overridden from UNiagaraScriptBase

		Name	Description
	TConstArrayV...	GetSimulationStageMetaData()
	void	ModifyCompilationEnvironment ( EShaderPlatform Platform, FShaderCompilerEnvironment& OutEnv... )
	bool	ShouldCompile ( EShaderPlatform Platform )

Overridden from UObject

	Name	Description
void	BeginCacheForCookedPlatformData ( const ITargetPlatform* TargetP... )	Starts caching of platform specific data for the target platform Called when cooking before serialization so that object can prepare platform specific data Not called during normal loading of objects
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	IsCachedCookedPlatformDataLoaded ( const ITargetPlatform* TargetP... )	Have we finished loading all the cooked platform data for the target platforms requested in BeginCacheForCookedPlatformData
bool	IsEditorOnly()	Called during saving to determine if the object is forced to be editor only or not
bool	IsReadyForFinishDestroy()	Called to check if the object is ready for FinishDestroy.
void	PostEditChangeProperty ( FPropertyChangedEvent& PropertyCha... )	Called when a property on this object has been modified externally
void	PostEditUndo()	Called after applying a transaction to the object.
void	PostLoad()	Do any object-specific cleanup required immediately after loading an object.
void	PreSave ( FObjectPreSaveContext SaveContext )	Presave function.
void	Serialize ( FArchive& Ar )	Handles reading, writing, and reference collecting using FArchive.

Overridden from FNiagaraVersionedObject

	Name	Description
FGuid	AddNewVersion ( int32 MajorVersion, int32 MinorVersion )	Creates a new data entry for the given version number.
void	DeleteVersion ( const FGuid& VersionGuid )	Deletes the version data for an existing version.
void	DisableVersioning ( const FGuid& VersionGuidToUse )	Disables versioning and keeps only the data from the given version guid.
void	EnableVersioning()	Enables versioning for this script asset.
void	ExposeVersion ( const FGuid& VersionGuid )	Changes the exposed version. Does nothing if the guid does not exist in the script's version data.
FNiagaraAsse...	FindVersionData ( const FGuid& VersionGuid )	Returns the version data for the given guid, if it exists. Otherwise returns nullptr.
TArray< FNia...	GetAllAvailableVersions()	Returns all available versions for this script.
FNiagaraAsse...	GetExposedVersion()	Returns the version of the exposed version data (i.e. the version used when adding a module to the stack)
TSharedPtr< ...	GetVersionDataAccessor ( const FGuid& Version )
bool	IsVersioningEnabled()	If true then this script asset uses active version control to track changes.

Typedefs

Name	Description
FOnPropertyChanged
FOnScriptCompiled

Constants

Name	Description
LogCompileStaticVars
NiagaraCustomVersionTagName

Deprecated Variables

	Name	Description
uint32: 1	bDeprecated_DEPRECATED	Use property in struct returned from GetScriptData() instead
uint32: 1	bExperimental_DEPRECATED	Use property in struct returned from GetScriptData() instead
uint32: 1	bExposeToLibrary_DEPRECATED	Deprecated, use LibraryVisibility instead.
FText	Category_DEPRECATED	Use property in struct returned from GetScriptData() instead
FText	CollapsedViewFormat_DEPRECATED	Deprecated, use LibraryVisibility instead.
TSubclassOf< UN...	ConversionUtility_DEPRECATED	Use property in struct returned from GetScriptData() instead
FText	DeprecationMessage_DEPRECATED	Use property in struct returned from GetScriptData() instead
TObjectPtr< UNi...	DeprecationRecommendation_DEPRECATED	Use property in struct returned from GetScriptData() instead
FText	Description_DEPRECATED	Use property in struct returned from GetScriptData() instead
FText	ExperimentalMessage_DEPRECATED	Use property in struct returned from GetScriptData() instead
FText	Keywords_DEPRECATED	Use property in struct returned from GetScriptData() instead
ENiagaraScriptL...	LibraryVisibility_DEPRECATED	Use property in struct returned from GetScriptData() instead
int32	ModuleUsageBitmask_DEPRECATED	Use property in struct returned from GetScriptData() instead
FText	NoteMessage_DEPRECATED	Use property in struct returned from GetScriptData() instead
ENiagaraNumeric...	NumericOutputTypeSelectionMode_DEPRECATED	Use property in struct returned from GetScriptData() instead
TArray< FName >	ProvidedDependencies_DEPRECATED	Use property in struct returned from GetScriptData() instead
TArray< FNiagar...	RequiredDependencies_DEPRECATED	Use property in struct returned from GetScriptData() instead
TMap< FName, FS...	ScriptMetaData_DEPRECATED	Deprecated, use LibraryVisibility instead.
TObjectPtr< cla...	Source_DEPRECATED	'Source' data/graphs for this script
int32	UsageIndex_DEPRECATED	Which instance of the usage in the graph to use. This is now deprecated and is handled by UsageId.

Deprecated Functions

		Name	Description
	PRAGMA_DISAB...	PreSave ( const ITargetPlatform* TargetP... )	Use version that takes FObjectPreSaveContext instead.

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