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UNiagaraScript

Scripts are function graphs that define the runtime execution for a Niagara system (similar to a Blueprint).

API > API/Plugins > API/Plugins/Niagara

Inheritance Hierarchy

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

Scripts are function graphs that define the runtime execution for a Niagara system (similar to a Blueprint).

There are three types of scripts: 1) Module: can be added as a standalone part to the emitter stack and encapsulates a single behavior, for example "Add Velocity" 2) Dynamic input: has a single output value and can be added to any input in the stack to compute such a value, for example "Random Vector" 3) Function: usually reserved for helper functions; can only be called from within modules or dynamic inputs

Variables

  Type Name Description
Public variable UProperty FNiagaraParameterStore RapidIterationParameters Contains all of the top-level values that are iterated on in the UI.
Public variable UProperty FNiagaraParameterStore RapidIterationParametersCookedEditorCache  
Public variable UProperty assetregistrysearchable ENiagaraScriptUsage Usage How this script is to be used. cannot be private due to use of GET_MEMBER_NAME_CHECKED
Public variable UProperty Category, EditAnywhere instanced TArray< TObjectPtr< UNiagaraValidationRule > > ValidationRules A set of rules to apply when this script is used in the stack.
Public variable UProperty Transient FGuid VersionToOpenInEditor This is used as a transient value to open a specific version in the graph editor

Constructors

  Type Name Description
Public function    
Public function  

UNiagaraScript ( const FObjectInitializer& ObjectInitializer
)

  

Functions

  Type Name Description
Public function bool

ApplyRapidIterationParameters ( TConstArrayView< FNiagaraVariable > InParameters,
bool bAllowRemoval
)

 Updates the RI parameter store based on the provided variables (missing entries will be added and stale entries will be removed. Returns true if the parameter store was modified.
Public function Static bool Infrastructure for GPU compute Shaders.
Public function Const bool

AreScriptAndSourceSynchronized ( const FGuid& VersionGuid
)

 Determine if the Script and its source graph are in sync.
Public function void  
Public function Static bool

BinaryToExecData ( const UNiagaraScript* Script,
const TArray< uint8 >& InBinaryData,
FNiagaraVMExecutableData& OutExecData
)

 Helper to convert the struct from its binary data out of the DDC to it's actual in-memory version.
Public function Static void Called from UNiagaraSystem::AppendToClassSchema() to collect the Script specific details for iterative cooking
Public function Static FString

BuildNiagaraDDCKeyString ( const FNiagaraVMExecutableDataId& CompileId,
const FString& ScriptPath
)

 Builds the DDC string for the derived data cache using the supplied CompiledId and ScriptPath
Public function void

CacheResourceShadersForCooking ( EShaderPlatform ShaderPlatform,
TArray< TUniquePtr< FNiagaraShaderScript > >& InOutCachedResources,
const ITargetPlatform* TargetPlatform
)

  
Public function void

CacheResourceShadersForRendering ( bool bRegenerateId,
bool bForceRecompile
)

  
Public function void

CacheShadersForResources ( FNiagaraShaderScript* ResourceToCache,
bool bApplyCompletedShaderMapForRendering,
bool bForceRecompile,
bool bCooking,
const ITargetPlatform* TargetPlatform
)

  
Public function Const bool  
Public function void Makes sure that the default version data is available and fixes old script assets.
Public function void Clears out resolved runtime data.
Public function Const void  
Public function Static bool  
Public function Const bool  
Public function Static bool  
Public function UNiagaraScript * Creates a shallow transient copy of this script for compilation purposes.
Public function Const bool

DidScriptCompilationSucceed ( bool bGPUScript
)

  
Public function Static bool

ExecToBinaryData ( const UNiagaraScript* Script,
TArray< uint8 >& OutBinaryData,
FNiagaraVMExecutableData& InExecData
)

 Reverse of the BinaryToExecData() function
Public function Const TArray< FName >

FindShaderFormatsForCooking ( const ITargetPlatform* TargetPlatform
)

  
Public function Const void Use of this function differs from the above in that the data is being pulled from the RapidIterationParameters rather than the compiled data
Public function void  
Public function Const FGuid

GetBaseChangeID ( const FGuid& VersionGuid
)

  
Public function Const TConstArrayView< FNiagaraScriptDataInterfaceInfo >  
Public function TArray< FNiagaraScriptDataInterfaceInfo > &  
Public function Const TConstArrayView< FNiagaraScriptUObjectCompileInfo >  
Public function TArrayView< FNiagaraScriptUObjectCompileInfo >  
Public function TArray< TObjectPtr< UNiagaraParameterCollection > > &  
Public function Const TOptional< T >  
Public function Const TOptional< FVector3d >

GetCompilerTag ( const FNiagaraVariableBase& InVar,
const FNiagaraParameterStore* FallbackParameterStore
)

  
Public function Const TOptional< T >

GetCompilerTag ( const FNiagaraVariableBase& InVar,
const FNiagaraParameterStore* FallbackParameterStore
)

  
Public function Const const FNiagaraVMExecutableDataId &  
Public function Const TConstArrayView< FNiagaraDataInterfaceGPUParamInfo >  
Public function FText

GetDescription ( const FGuid& VersionGuid
)

  
Public function const FNiagaraScriptExecutionParameterStore *  
Public function Const FString  
Public function Const ENiagaraScriptCompileStatus  
Public function Const const FVersionedNiagaraScriptData *  
Public function FVersionedNiagaraScriptData * Returns the script data for latest exposed version.
Public function Const const UNiagaraScriptSourceBase *  
Public function UNiagaraScriptSourceBase *  
Public function FString

GetNiagaraDDCKeyString ( const FGuid& ScriptVersion,
const FString& ScriptPath
)

 Creates a string key for the derived data cache
Public function Const FVersionedNiagaraEmitter Workaround for emitter versioning because we used a lot of Script->GetOuter() previously.
Public function Static ERHIFeatureLevel::Type  
Public function Const const FNiagaraShaderScript *  
Public function FNiagaraShaderScript *  
Public function Const TConstArrayView< FNiagaraScriptResolvedDataInterfaceInfo >  
Public function Const TConstArrayView< FNiagaraResolvedUObjectInfo >  
Public function Const TConstArrayView< FNiagaraResolvedUserDataInterfaceBinding >  
Public function Const const FVersionedNiagaraScriptData *

GetScriptData ( const FGuid& VersionGuid
)

  
Public function FVersionedNiagaraScriptData *

GetScriptData ( const FGuid& VersionGuid
)

 Returns the script data for a specific version or nullptr if no such version is found.
Public function UNiagaraScriptSourceBase *

GetSource ( const FGuid& VersionGuid
)

  
Public function Const const UNiagaraScriptSourceBase *

GetSource ( const FGuid& VersionGuid
)

  
Public function Static TArray< ENiagaraScriptUsage >

GetSupportedUsageContextsForBitmask ( int32 InModuleUsageBitmask,
bool bIncludeHiddenUsages
)

  
Public function Const ENiagaraScriptUsage  
Public function Const FGuid  
Public function Const const FNiagaraVMExecutableData &  
Public function FNiagaraVMExecutableData &  
Public function Const const FNiagaraVMExecutableDataId &  
Public function FGraphEventRef

HandleByteCodeOptimization ( bool bShouldForceNow
)

 Kicks off an async job to convert the ByteCode into an optimized version for the platform we are running on.
Public function bool

HandleVariableRenames ( const TMap< FNiagaraVariable, FNiagaraVariable >& OldToNewVars,
const FString& UniqueEmitterName
)

  
Public function Const bool  
Public function void

InvalidateCompileResults ( const FString& Reason
)

  
Public function void  
Public function Static bool  
Public function Const bool  
Public function Static bool  
Public function Const bool  
Public function Static bool  
Public function Const bool  
Public function Static bool  
Public function Static bool  
Public function Const bool  
Public function Const bool  
Public function Static bool  
Public function Const bool  
Public function Static bool  
Public function Static bool  
Public function Const bool  
Public function Static bool  
Public function Const bool  
Public function Static bool  
Public function Const bool  
Public function Static bool  
Public function Const bool  
Public function Const bool  
Public function Static bool  
Public function Const bool  
Public function Static bool  
Public function Static bool  
Public function Const bool  
Public function Static bool  
Public function Const bool  
Public function Static bool  
Public function Const bool  
Public function Const bool

IsScriptCompilationPending ( bool bGPUScript
)

  
Public function Const bool  
Public function Const bool

IsScriptShaderSynchronized ( const FGuid& VersionGuid
)

  
Public function Const bool

IsShaderMapCached ( const ITargetPlatform* TargetPlatform,
const FNiagaraShaderMapId& ShaderMapId
)

  
Public function Const bool  
Public function Static bool  
Public function Const bool  
Public function Static bool  
Public function Static bool

IsSupportedUsageContextForBitmask ( int32 InModuleUsageBitmask,
ENiagaraScriptUsage InUsageContext,
bool bIncludeHiddenUsages
)

  
Public function Static bool  
Public function Const bool  
Public function Static bool  
Public function Static bool  
Public function Const bool  
Public function Static bool Is usage A dependent on Usage B?
Public function void

MarkScriptAndSourceDesynchronized ( FString Reason,
const FGuid& VersionGuid
)

 Ensure that the Script and its source graph are marked out of sync.
Public function FOnScriptCompiled & Callback issued whenever a GPU script compilation successfully happened (even if the results are a script that cannot be executed due to errors)
Public function FOnPropertyChanged & Callback issues whenever post edit changed is called on this script.
Public function FOnScriptCompiled & Callback issued whenever a VM script compilation successfully happened (even if the results are a script that cannot be executed due to errors)
Public function Virtual void

PostEditChangeVersionedProperty ( FPropertyChangedEvent& PropertyChangedEvent,
const FGuid& Version
)

  
Public function UFunction void  
Public function void

RequestCompile ( const FGuid& ScriptVersion,
bool bForceCompile
)

 Request a synchronous compile for the script, possibly forcing it to compile.
Public function bool Request an asynchronous compile for the script, possibly forcing it to compile.
Public function void  
Public function void

SetComputeCompilationResults ( const ITargetPlatform* TargetPlatform,
EShaderPlatform ShaderPlatform,
ERHIFeatureLevel::Type FeatureLevel,
const FNiagaraShaderScriptParametersMetadata& SharedParameters,
const FNiagaraShaderMapRef& ShaderMap,
TConstArrayView< FShaderCompilerError > CompilationErrors
)

  
Public function void  
Public function Static void  
Public function void  
Public function void

SetResolvedUObjects ( TConstArrayView< FNiagaraResolvedUObjectInfo > InResolvedUObjectInfos
)

  
Public function void  
Public function void

SetSource ( UNiagaraScriptSourceBase* InSource,
const FGuid& VersionGuid
)

  
Public function void  
Public function void

SetUsageId ( const FGuid& InUsageId
)

  
Public function void

SetVMCompilationResults ( const FNiagaraVMExecutableDataId& InCompileId,
FNiagaraVMExecutableData& InScriptVM,
const FString& EmitterUniqueName,
const TMap< FName, UNiagaraDataInterface* >& ObjectNameMap,
bool ApplyRapidIterationParameters
)

 External call used to identify the values for a successful VM script compilation.
Public function Static bool  
Public function void

SyncAliases ( const FNiagaraAliasContext& ResolveAliasesContext
)

  
Public function bool

SynchronizeExecutablesWithCompilation ( const UNiagaraScript* Script,
const TMap< FString, FString >& RenameMap
)

 In the event where we "merge" we duplicate the changes of the source script onto the newly cloned copy.
Public function Const bool  

Overridden from UNiagaraScriptBase

  Type Name Description
Public function Virtual Const TConstArrayView< FSimulationStageMetaData >  
Public function Virtual Const void  
Public function Virtual Const bool  

Overridden from UObject

  Type Name Description
Public function Virtual void 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
Public function Virtual void Called before destroying the object.
Public function Virtual Const void 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
Public function Virtual Const void

GetAssetRegistryTags ( TArray< FAssetRegistryTag >& OutTags
)

  
Public function Virtual bool Have we finished loading all the cooked platform data for the target platforms requested in BeginCacheForCookedPlatformData
Public function Virtual Const bool Called during saving to determine if the object is forced to be editor only or not
Public function Virtual bool Called to check if the object is ready for FinishDestroy.
Public function Virtual void

PostEditChangeProperty ( FPropertyChangedEvent& PropertyChangedEvent
)

 Called when a property on this object has been modified externally
Public function Virtual void Called after applying a transaction to the object.
Public function Virtual void Do any object-specific cleanup required immediately after loading an object.
Public function Virtual void

PreSave ( FObjectPreSaveContext ObjectSaveContext
)

 Presave function.
Public function Virtual void Handles reading, writing, and reference collecting using FArchive.

Overridden from FNiagaraVersionedObject

  Type Name Description
Public function Virtual FGuid

AddNewVersion ( int32 MajorVersion,
int32 MinorVersion
)

 Creates a new data entry for the given version number.
Public function Virtual void

DeleteVersion ( const FGuid& VersionGuid
)

 Deletes the version data for an existing version.
Public function Virtual void

DisableVersioning ( const FGuid& VersionGuidToUse
)

 Disables versioning and keeps only the data from the given version guid.
Public function Virtual void Enables versioning for this script asset.
Public function Virtual void

ExposeVersion ( const FGuid& VersionGuid
)

 Changes the exposed version. Does nothing if the guid does not exist in the script's version data.
Public function Virtual Const FNiagaraAssetVersion const *

FindVersionData ( const FGuid& VersionGuid
)

 Returns the version data for the given guid, if it exists. Otherwise returns nullptr.
Public function Virtual Const TArray< FNiagaraAssetVersion > Returns all available versions for this script.
Public function Virtual Const FNiagaraAssetVersion Returns the version of the exposed version data (i.e. the version used when adding a module to the stack)
Public function Virtual TSharedPtr< FNiagaraVersionDataAccessor >

GetVersionDataAccessor ( const FGuid& Version
)

  
Public function Virtual Const bool 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

  Type Name Description
Public variable UProperty Meta uint32: 1 bDeprecated_DEPRECATED Use property in struct returned from GetScriptData() instead
Public variable UProperty Meta uint32: 1 bExperimental_DEPRECATED Use property in struct returned from GetScriptData() instead
Public variable UProperty Meta uint32: 1 bExposeToLibrary_DEPRECATED Deprecated, use LibraryVisibility instead.
Public variable UProperty Meta FText Category_DEPRECATED Use property in struct returned from GetScriptData() instead
Public variable UProperty Meta FText CollapsedViewFormat_DEPRECATED Deprecated, use LibraryVisibility instead.
Public variable UProperty Meta TSubclassOf< UNiagaraConvertInPlaceUtilityBase > ConversionUtility_DEPRECATED Use property in struct returned from GetScriptData() instead
Public variable UProperty Meta FText DeprecationMessage_DEPRECATED Use property in struct returned from GetScriptData() instead
Public variable UProperty Meta TObjectPtr< UNiagaraScript > DeprecationRecommendation_DEPRECATED Use property in struct returned from GetScriptData() instead
Public variable UProperty Meta FText Description_DEPRECATED Use property in struct returned from GetScriptData() instead
Public variable UProperty Meta FText ExperimentalMessage_DEPRECATED Use property in struct returned from GetScriptData() instead
Public variable UProperty Meta FText Keywords_DEPRECATED Use property in struct returned from GetScriptData() instead
Public variable UProperty Meta ENiagaraScriptLibraryVisibility LibraryVisibility_DEPRECATED Use property in struct returned from GetScriptData() instead
Public variable UProperty Meta int32 ModuleUsageBitmask_DEPRECATED Use property in struct returned from GetScriptData() instead
Public variable UProperty Meta FText NoteMessage_DEPRECATED Use property in struct returned from GetScriptData() instead
Public variable UProperty Meta ENiagaraNumericOutputTypeSelectionMode NumericOutputTypeSelectionMode_DEPRECATED Use property in struct returned from GetScriptData() instead
Public variable UProperty Meta TArray< FName > ProvidedDependencies_DEPRECATED Use property in struct returned from GetScriptData() instead
Public variable UProperty Meta TArray< FNiagaraModuleDependency > RequiredDependencies_DEPRECATED Use property in struct returned from GetScriptData() instead
Public variable UProperty Meta TMap< FName, FString > ScriptMetaData_DEPRECATED Deprecated, use LibraryVisibility instead.
Public variable UProperty Meta TObjectPtr< class UNiagaraScriptSourceBase > Source_DEPRECATED 'Source' data/graphs for this script
Public variable UProperty int32 UsageIndex_DEPRECATED Which instance of the usage in the graph to use. This is now deprecated and is handled by UsageId.

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