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> Unreal Engine API Reference > Plugins > Niagara > FNiagaraSystemInstance

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FNiagaraSystemInstance

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References

Module	Niagara
Header	/Engine/Plugins/FX/Niagara/Source/Niagara/Public/NiagaraSystemInstance.h
Include	#include "NiagaraSystemInstance.h"

Syntax

class FNiagaraSystemInstance

Variables

	Name	Description
uint32	ActiveGPUEmitterCount
FInstanceParame...	GatheredInstanceParameters
int32	GPUDataInterfaceInstanceDataSize
TArray< TPair< ...	GPUDataInterfaces
bool	GPUParamIncludeInterpolation
ENiagaraSystemI...	SystemInstanceState
uint32	TotalGPUParamSize	Transient data that is accumulated during tick.

Constructors

	Name	Description
	FNiagaraSystemInstance ( UWorld& InWorld, UNiagaraSystem& InAsset, FNiagaraUserRedirectionParameterSto..., USceneComponent* InAttachCompo..., ENiagaraTickBehavior InTickBehavior, bool bInPooled )	Creates a new Niagara system instance.

Destructors

	Name	Description
	~FNiagaraSystemInstance()	Cleanup

Functions

	Name	Description
void	Activate ( EResetMode InResetMode )
void	AdvanceSimulation ( int32 TickCountToSimulate, float TickDeltaSeconds )	Manually advances this system's simulation by the specified number of ticks and tick delta.
bool	AllocateSystemInstance ( TUniquePtr< FNiagaraSystemInstance ..., UWorld& InWorld, UNiagaraSystem& InAsset, FNiagaraUserRedirectionParameterSto..., USceneComponent* InAttachCompo..., ENiagaraTickBehavior InTickBehavior, bool bInPooled )
void	BindParameters()	Void RebindParameterCollection(UNiagaraParameterCollectionInstance* OldInstance, UNiagaraParameterCollectionInstance* NewInstance);
ETickingGrou...	CalculateTickGroup()	Calculates which tick group the instance should be in.
void	Cleanup()
void	ClearEventDataSets()
void	Complete ( bool bExternalCompletion )
FNiagaraData...	CreateEventDataSet ( FName EmitterName, FName EventName )
void	Deactivate ( bool bImmediate )
bool	DeallocateSystemInstance ( TUniquePtr< FNiagaraSystemInstance ... )
void	Dump()	Dumps all of this systems info to the log.
void	DumpTickInfo ( FOutputDevice& Ar )	Dumps information about the instances tick to the log
FNiagaraEmit...	EditEmitterParameters ( int32 EmitterIdx )
void	EvaluateBoundFunction ( FName FunctionName, bool& UsedOnCpu, bool& UsedOnGpu )
void	FinalizeTick_GameThread ( bool bEnqueueGPUTickIfNeeded )	Final phase of system instance tick.
void *	FindDataInterfaceInstanceData ( UNiagaraDataInterface* Interfa... )	Returns the instance data for a particular interface for this System.
void	FinishCapture()	Only call from within the script execution states. Does nothing if not capturing a frame.
void	FlipParameterBuffers()
void	GenerateAndSubmitGPUTick()
TArray< TSha...	GetActiveCaptureResults()	Only call from within the script execution states. Value is null if not capturing a frame.
TSharedPtr< ...	GetActiveCaptureWrite ( const FName& InHandleName, ENiagaraScriptUsage InUsage, const FGuid& InUsageId )	Only call from within the script execution states. Value is nullptr if not capturing a frame.
ENiagaraExec...	GetActualExecutionState()
float	GetAge()
bool	GetAreDataInterfacesInitialized()
USceneCompon...	GetAttachComponent()
NiagaraEmitt...	GetBatcher()
const FStrin...	GetCrashReporterTag()
FNiagaraEmit...	GetEmitterByID ( FGuid InID )
TConstArrayV...	GetEmitterExecutionOrder()
const FNiaga...	GetEmitterParameters ( int32 EmitterIdx, bool PreviousFrame )
TArray< TSha...	GetEmitters()
const TArray...	GetEmitters()
FNiagaraData...	GetEventDataSet ( FName EmitterName, FName EventName )
ERHIFeatureL...	GetFeatureLevel()
const FNiaga...	GetGlobalParameters ( bool PreviousFrame )
FNiagaraSyst...	GetId()
FNiagaraPara...	GetInstanceParameters()
bool	GetIsolateEnabled()
float	GetLastRenderTime()
const FBox &	GetLocalBounds()
float	GetLODDistance()	Calculates the distance to use for distance based LODing / culling.
float	GetMaxLODDistance()
FNiagaraUser...	GetOverrideParameters()
const FNiaga...	GetOverrideParameters()
const FNiaga...	GetOwnerParameters ( bool PreviousFrame )
UNiagaraPara...	GetParameterCollectionInstance ( UNiagaraParameterCollection* C... )
uint32	GetParameterIndex ( bool PreviousFrame )
const FNiaga...	GetPerInstanceDIFunction ( ENiagaraSystemSimulationScript Scri..., int32 FuncIndex )
UActorCompon...	GetPrereqComponent()
int32	GetRandomSeedOffset()
ENiagaraExec...	GetRequestedExecutionState()
TSharedPtr< ...	GetSimulationForHandle ( const FNiagaraEmitterHandle& Emitt... )	Gets the simulation for the supplied emitter handle.
UNiagaraSyst...	GetSystem()
FNiagaraSyst...	GetSystemGpuComputeProxy()
int32	GetSystemInstanceIndex()
const FNiaga...	GetSystemParameters ( bool PreviousFrame )
TSharedPtr< ...	GetSystemSimulation()
ENiagaraTick...	GetTickBehavior()	Get the current tick behavior
int32	GetTickCount()
UWorld *	GetWorld()
FNiagaraWorl...	GetWorldManager()
const FTrans...	GetWorldTransform()	Gets the current world transform of the system
bool	HandleCompletion()	Handles completion of the system and returns true if the system is complete.
bool	HandleNeedsUIResync()
bool	HasGPUEmitters()	Void SetHasGPUEmitters(bool bInHasGPUEmitters) { bHasGPUEmitters = bInHasGPUEmitters; }
bool	HasPendingFinalize()
void	Init ( bool bInForceSolo )	Initializes this System instance to simulate the supplied System.
void	InitGPUTick ( FNiagaraGPUSystemTick& OutTick )
bool	IsComplete()	Int32 GetNumParticles(int32 EmitterIndex) const { return ParameterNumParticleBindings[EmitterIndex].GetValue(); } float GetSpawnCountScale(int32 EmitterIndex) const { return ParameterSpawnCountScaleBindings[EmitterIndex].GetValue(); }
bool	IsDisabled()
bool	IsPaused()
bool	IsPendingSpawn()
bool	IsReadyToRun()
bool	IsSolo()
void	ManualTick ( float DeltaSeconds, const FGraphEventRef& MyCompletion... )
bool	NeedsGPUTick()
FOnDestroyed...	OnDestroyed()
FOnInitializ...	OnInitialized()	Gets a multicast delegate which is called whenever this instance is initialized with an System asset.
void	OnPooledReuse ( UWorld& NewWorld )
FOnReset &	OnReset()	Gets a multicast delegate which is called whenever this instance is reset due to external changes in the source System asset.
void	OnSimulationDestroyed()
bool	QueryCaptureResults ( const FGuid& RequestId, TArray< TSharedPtr< struct FNiagara... )	Poll for previous frame capture requests.
void	RaiseNeedsUIResync()
bool	RequestCapture ( const FGuid& RequestId )	Request that this simulation capture a frame. Cannot capture if disabled or already completed.
bool	RequiresDepthBuffer()
bool	RequiresDistanceFieldData()
bool	RequiresEarlyViewData()
bool	RequiresViewUniformBuffer()
void	Reset ( EResetMode Mode )	Requests the the simulation be reset on the next tick.
void	SetActualExecutionState ( ENiagaraExecutionState InState )
void	SetEmitterEnable ( FName EmitterName, bool bNewEnableState )
void	SetGpuComputeDebug ( bool bEnableDebug )
void	SetLastRenderTime ( float TimeSeconds )
void	SetLODDistance ( float InLODDistance, float InMaxLODDistance )
void	SetOnComplete ( const FOnComplete& InOnCompleteDel... )	Gets a multicast delegate which is called whenever this instance is complete.
void	SetOnPostTick ( const FOnPostTick& InPostTickDeleg... )	Gets a multicast delegate which is called after this instance has finished ticking for the frame on the game thread
void	SetPaused ( bool bInPaused )
void	SetPendingFinalize ( FNiagaraSystemInstanceFinalizeRef I... )
void	SetRandomSeedOffset ( int32 Offset )
void	SetRequestedExecutionState ( ENiagaraExecutionState InState )
void	SetSolo ( bool bInSolo )
void	SetSystemSignificanceIndex ( int32 InIndex )	The significant index for this component.
void	SetTickBehavior ( ENiagaraTickBehavior NewTickBehavio... )	Set a new tick behavior, this will not move the instance straight away and will wait until the next time it is evaluated
void	SetWorldTransform ( const FTransform& InTransform )	Sets the world transform
bool	ShouldCaptureThisFrame()	Only call from within the script execution states. Value is false if not capturing a frame.
void	Tick_Concurrent ( bool bEnqueueGPUTickIfNeeded )	Secondary phase of the system instance tick that can be executed on any thread.
void	Tick_GameThread ( float DeltaSeconds )	Initial phase of system instance tick. Must be executed on the game thread.
void	TickDataInterfaces ( float DeltaSeconds, bool bPostSimulate )	Perform per-tick updates on data interfaces that need it.
void	TickInstanceParameters_Concurrent()
void	TickInstanceParameters_GameThread ( float DeltaSeconds )
void	UnbindParameters ( bool bFromComplete )
bool	UsesCollection ( const UNiagaraParameterCollection&... )	Bool UsesDataInterface(UNiagaraDataInterface* Interface);
bool	UsesEmitter ( const UNiagaraEmitter* Emitter )
bool	UsesScript ( const UNiagaraScript* Script )
void	WaitForConcurrentTickAndFinalize ( bool bEnsureComplete )	Wait for any pending concurrent work to complete, must be called on the GameThread.
void	WaitForConcurrentTickDoNotFinalize ( bool bEnsureComplete )	Wait for any pending concurrent work to complete, must be called on the GameThread.

Classes

	Name	Description
	FInstanceParameters

Enums

	Name	Description
	EResetMode	Defines modes for resetting the System instance.

Typedefs

Name	Description
EmitterEventKey	Registered events for each of the emitters
EventDataSetMap
FOnComplete
FOnDestroyed
FOnInitialized
FOnPostTick
FOnReset

Constants

Name	Description
ParameterBufferCount

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