UNiagaraSystem Class Reference

A Niagara System contains multiple Niagara Emitters to create various effects. Niagara Systems can be placed in the world, unlike Emitters, and expose User Parameters to configure an effect at runtime. More...

Public Member Functions
Functions
void	SetbOverrideTranslucencySortPriority (bool Value)
void	SetbBakeOutRapidIterationOnCook (bool Value)
	When enabled constant values are baked into scripts to improve performance.
void	SetbCompressAttributes (bool Value)
	Toggles whether or not emitters within this system will try and compress their particle attributes. In some cases, this precision change can lead to perceivable differences, but memory costs and or performance (especially true for GPU emitters) can improve.
void	SetbTrimAttributes (bool Value)
	When enabled we trim particle attributes while editing the system.
void	SetbTrimAttributesOnCook (bool Value)
	If true Particle attributes will be removed from the DataSet if they are unnecessary (are never read by ParameterMap).
void	SetbIgnoreParticleReadsForAttributeTrim (bool Value)
	If true ParticleReads will not absolutely prevent attribute trimming - User must ensure that the appropriate attributes are preserved on the source emitter!
void	SetbDisableDebugSwitches (bool Value)
	When enable debug switches are disabled while editing the system.
void	SetbDisableDebugSwitchesOnCook (bool Value)
	When enabled debug switches are disabled when compiling the system.
void	SetbSupportLargeWorldCoordinates (bool Value)
	If true then position type values will be rebased on system activation to fit into a float precision vector. This needs to be turned off when using a custom data interface or renderer that does not support the rebasing.
void	SetbOverrideCastShadow (bool Value)
	Various optional overrides for component properties when spawning a system.
void	SetbOverrideReceivesDecals (bool Value)
void	SetbOverrideRenderCustomDepth (bool Value)
void	SetbOverrideCustomDepthStencilValue (bool Value)
void	SetbOverrideCustomDepthStencilWriteMask (bool Value)
void	SetbBakeOutRapidIteration (bool Value)
	When enable constant values are baked into the scripts while editing the system, this will increase iteration times but improve performance.
void	SetbOverrideTranslucencySortDistanceOffset (bool Value)
bool	GetbCastShadow () const
	When enabled this is the default value set on the component. Controls whether the primitive component should cast a shadow or not.
void	SetbCastShadow (bool Value)
	When enabled this is the default value set on the component. Controls whether the primitive component should cast a shadow or not.
bool	GetbReceivesDecals () const
	When enabled this is the default value set on the component. Whether the primitive receives decals.
void	SetbReceivesDecals (bool Value)
	When enabled this is the default value set on the component. Whether the primitive receives decals.
bool	GetbRenderCustomDepth () const
	When enabled this is the default value set on the component. This primitive has bRenderCustomDepth enabled.
void	SetbRenderCustomDepth (bool Value)
	When enabled this is the default value set on the component. This primitive has bRenderCustomDepth enabled.
void	SetbDisableExperimentalVM (bool Value)
	If true, disables optimized VM, if available.
void	SetbInitialOwnerVelocityFromActor (bool Value)
	When enabled we use the owner actor's velocity for the first frame. If we do not have an owner actor, or this is disable then the first frame's velocity will be zero.
void	SetbFixedBounds (bool Value)
	Whether or not fixed bounds are enabled.
void	SetbOverrideAllowCullingForLocalPlayers (bool Value)
	Controls whether we should override the Effect Type value for bAllowCullingForLocalPlayers.
void	SetbAllowCullingForLocalPlayersOverride (bool Value)
	The override value for bAllowCullingForLocalPlayers from the Effect Type.
void	SetbAllowSystemStateFastPath (bool Value)
	When enabled if all emitters don't require script execution and the system script is empty / constant we can invoke a faster CPU path.
Public Member Functions inherited from UObject
bool	MarkPackageDirty () const
void	RemoveFromRoot ()
bool	GetIsRooted () const
bool	IsTransient () const
bool	Modify (bool bAlwaysMarkDirty=true)
void	SetTransactional (bool bTransactional)
bool	IsSupportedForNetworking () const
UClass	GetClass () const
UObject	GetOuter () const
UObject	GetTypedOuter (TSubclassOf< UObject > Target) const
	Traverses the outer chain searching for the next object of a certain type.
UPackage	GetOutermost () const
UPackage	GetPackage () const
void	AddToRoot ()
UWorld	GetWorld () const
FName	GetName () const
FString	GetFullName (const UObject StopOuter=nullptr) const
FString	GetPathName (const UObject StopOuter=nullptr) const
bool	IsA (const UClass Class) const
	Returns true if this object is of the specified type, or a child of that type.
void	SaveConfig ()
void	LoadConfig ()
void	ReloadConfig ()
void	CopyScriptPropertiesFrom (const UObject OtherObject)
void	opCast (?&Address) const
FString	ToString () const

Static Public Member Functions
Static Functions
static UClass	StaticClass ()
Static Public Member Functions inherited from UFXSystemAsset
static UClass	StaticClass ()
Static Public Member Functions inherited from UObject
static UClass	StaticClass ()

Public Attributes
Asset Options
FText	TemplateAssetDescription
Debug
bool	bDumpDebugEmitterInfo
bool	bDumpDebugSystemInfo
Performance
bool	bRequireCurrentFrameData
	When enabled, we follow the settings on the UNiagaraComponent for tick order. When this option is disabled, we ignore any dependencies from data interfaces or other variables and instead fire off the simulation as early in the frame as possible. This greatly reduces overhead and allows the game thread to run faster, but comes at a tradeoff if the dependencies might leave gaps or other visual artifacts.
Rendering
bool	bReceivesDecals
	When enabled this is the default value set on the component. Whether the primitive receives decals.
int	TranslucencySortPriority
	When enabled this is the default value set on the component. Adjusts the translucent object sorting priority, see PrimitiveComponent description for more details.
bool	bCastShadow
	When enabled this is the default value set on the component. Controls whether the primitive component should cast a shadow or not.
int	CustomDepthStencilValue
	When enabled this is the default value set on the component. Optionally write this 0-255 value to the stencil buffer in CustomDepth pass (Requires project setting or r.CustomDepth == 3).
float32	TranslucencySortDistanceOffset
	When enabled this is the default value set on the component. Modifies the sort distance for translucent objects, see PrimitiveComponent description for more details.
bool	bRenderCustomDepth
	When enabled this is the default value set on the component. This primitive has bRenderCustomDepth enabled.
ERendererStencilMask	CustomDepthStencilWriteMask
	When enabled this is the default value set on the component. Mask used for stencil buffer writes.
Scalability
FNiagaraSystemScalabilityOverrides	SystemScalabilityOverrides
bool	bOverrideScalabilitySettings
FNiagaraPlatformSet	Platforms
System
float32	WarmupTickDelta
	Delta time to use for warmup ticks.
int	RandomSeed
	Seed used for system script random number generator.
float32	WarmupTime
	Warm up time in seconds. Used to calculate WarmupTickCount. Rounds down to the nearest multiple of WarmupTickDelta.
int	WarmupTickCount
	Number of ticks to process for warmup. You can set by this or by time via WarmupTime.
bool	bDeterminism
	When disabled we will generate a RandomSeed per instance on reset which is not deterministic. When enabled we will always use the RandomSeed from the system plus the components RandomSeedOffset, this allows for determinism but variance between components.
bool	bFixedTickDelta
float32	FixedTickDeltaTime
	If activated, the system ticks with a fixed delta time instead of the varying game thread delta time. This leads to much more stable simulations. When the fixed tick delta is smaller than the game thread tick time the simulation is substepping by executing multiple ticks per frame. Note that activating this feature forces the system to tick on the game thread instead of an async task in parallel.
FBox	FixedBounds
	The fixed bounding box value for the whole system. When placed in the level and the bounding box is not visible to the camera, the effect is culled from rendering.
UNiagaraEffectType	EffectType
	An effect types defines settings shared between systems, for example scalability and validation rules. Things like environment fx usually have a different effect type than gameplay relevant fx such as weapon impacts. This way whole classes of effects can be adjusted at once.
TArray< TObjectPtr< UNiagaraParameterCollectionInstance > >	ParameterCollectionOverrides
Public Attributes inherited from UFXSystemAsset
uint	PoolPrimeSize
	How many instances we should use to initially prime the pool. This can amortize runtime activation cost by moving it to load time. Use with care as this could cause large hitches for systems loaded/unloaded during play rather than at level load.
uint	MaxPoolSize
	Max number of components of this system to keep resident in the world component pool.
Public Attributes inherited from UObject
const UClass	Class
const UObject	Outer
const UPackage	Outermost
const UPackage	Package
const UWorld	World
const FName	Name
const bool	IsRooted

Detailed Description

A Niagara System contains multiple Niagara Emitters to create various effects. Niagara Systems can be placed in the world, unlike Emitters, and expose User Parameters to configure an effect at runtime.

Member Function Documentation

GetbCastShadow()

bool GetbCastShadow

(

)

const

When enabled this is the default value set on the component. Controls whether the primitive component should cast a shadow or not.

GetbReceivesDecals()

bool GetbReceivesDecals

(

)

const

When enabled this is the default value set on the component. Whether the primitive receives decals.

GetbRenderCustomDepth()

bool GetbRenderCustomDepth

(

)

const

When enabled this is the default value set on the component. This primitive has bRenderCustomDepth enabled.

SetbAllowCullingForLocalPlayersOverride()

void SetbAllowCullingForLocalPlayersOverride

(

bool

Value

)

The override value for bAllowCullingForLocalPlayers from the Effect Type.

SetbAllowSystemStateFastPath()

void SetbAllowSystemStateFastPath

(

bool

Value

)

When enabled if all emitters don't require script execution and the system script is empty / constant we can invoke a faster CPU path.

SetbBakeOutRapidIteration()

void SetbBakeOutRapidIteration

(

bool

Value

)

When enable constant values are baked into the scripts while editing the system, this will increase iteration times but improve performance.

SetbBakeOutRapidIterationOnCook()

void SetbBakeOutRapidIterationOnCook

(

bool

Value

)

When enabled constant values are baked into scripts to improve performance.

SetbCastShadow()

void SetbCastShadow

(

bool

Value

)

When enabled this is the default value set on the component. Controls whether the primitive component should cast a shadow or not.

SetbCompressAttributes()

void SetbCompressAttributes

(

bool

Value

)

Toggles whether or not emitters within this system will try and compress their particle attributes. In some cases, this precision change can lead to perceivable differences, but memory costs and or performance (especially true for GPU emitters) can improve.

SetbDisableDebugSwitches()

void SetbDisableDebugSwitches

(

bool

Value

)

When enable debug switches are disabled while editing the system.

SetbDisableDebugSwitchesOnCook()

void SetbDisableDebugSwitchesOnCook

(

bool

Value

)

When enabled debug switches are disabled when compiling the system.

SetbDisableExperimentalVM()

void SetbDisableExperimentalVM

(

bool

Value

)

If true, disables optimized VM, if available.

SetbFixedBounds()

void SetbFixedBounds

(

bool

Value

)

Whether or not fixed bounds are enabled.

SetbIgnoreParticleReadsForAttributeTrim()

void SetbIgnoreParticleReadsForAttributeTrim

(

bool

Value

)

If true ParticleReads will not absolutely prevent attribute trimming - User must ensure that the appropriate attributes are preserved on the source emitter!

SetbInitialOwnerVelocityFromActor()

void SetbInitialOwnerVelocityFromActor

(

bool

Value

)

When enabled we use the owner actor's velocity for the first frame. If we do not have an owner actor, or this is disable then the first frame's velocity will be zero.

SetbOverrideAllowCullingForLocalPlayers()

void SetbOverrideAllowCullingForLocalPlayers

(

bool

Value

)

Controls whether we should override the Effect Type value for bAllowCullingForLocalPlayers.

SetbOverrideCastShadow()

void SetbOverrideCastShadow

(

bool

Value

)

Various optional overrides for component properties when spawning a system.

SetbOverrideCustomDepthStencilValue()

void SetbOverrideCustomDepthStencilValue

(

bool

Value

)

SetbOverrideCustomDepthStencilWriteMask()

void SetbOverrideCustomDepthStencilWriteMask

(

bool

Value

)

SetbOverrideReceivesDecals()

void SetbOverrideReceivesDecals

(

bool

Value

)

SetbOverrideRenderCustomDepth()

void SetbOverrideRenderCustomDepth

(

bool

Value

)

SetbOverrideTranslucencySortDistanceOffset()

void SetbOverrideTranslucencySortDistanceOffset

(

bool

Value

)

SetbOverrideTranslucencySortPriority()

void SetbOverrideTranslucencySortPriority

(

bool

Value

)

SetbReceivesDecals()

void SetbReceivesDecals

(

bool

Value

)

When enabled this is the default value set on the component. Whether the primitive receives decals.

SetbRenderCustomDepth()

void SetbRenderCustomDepth

(

bool

Value

)

When enabled this is the default value set on the component. This primitive has bRenderCustomDepth enabled.

SetbSupportLargeWorldCoordinates()

void SetbSupportLargeWorldCoordinates

(

bool

Value

)

If true then position type values will be rebased on system activation to fit into a float precision vector. This needs to be turned off when using a custom data interface or renderer that does not support the rebasing.

SetbTrimAttributes()

void SetbTrimAttributes

(

bool

Value

)

When enabled we trim particle attributes while editing the system.

SetbTrimAttributesOnCook()

void SetbTrimAttributesOnCook

(

bool

Value

)

If true Particle attributes will be removed from the DataSet if they are unnecessary (are never read by ParameterMap).

StaticClass()

UClass StaticClass ( )

static

Member Data Documentation

bCastShadow

bool bCastShadow

When enabled this is the default value set on the component. Controls whether the primitive component should cast a shadow or not.

bDeterminism

bool bDeterminism

When disabled we will generate a RandomSeed per instance on reset which is not deterministic. When enabled we will always use the RandomSeed from the system plus the components RandomSeedOffset, this allows for determinism but variance between components.

bDumpDebugEmitterInfo

bool bDumpDebugEmitterInfo

bDumpDebugSystemInfo

bool bDumpDebugSystemInfo

bFixedTickDelta

bool bFixedTickDelta

bOverrideScalabilitySettings

bool bOverrideScalabilitySettings

bReceivesDecals

bool bReceivesDecals

When enabled this is the default value set on the component. Whether the primitive receives decals.

bRenderCustomDepth

bool bRenderCustomDepth

When enabled this is the default value set on the component. This primitive has bRenderCustomDepth enabled.

bRequireCurrentFrameData

bool bRequireCurrentFrameData

When enabled, we follow the settings on the UNiagaraComponent for tick order. When this option is disabled, we ignore any dependencies from data interfaces or other variables and instead fire off the simulation as early in the frame as possible. This greatly reduces overhead and allows the game thread to run faster, but comes at a tradeoff if the dependencies might leave gaps or other visual artifacts.

CustomDepthStencilValue

int CustomDepthStencilValue

When enabled this is the default value set on the component. Optionally write this 0-255 value to the stencil buffer in CustomDepth pass (Requires project setting or r.CustomDepth == 3).

CustomDepthStencilWriteMask

ERendererStencilMask CustomDepthStencilWriteMask

When enabled this is the default value set on the component. Mask used for stencil buffer writes.

EffectType

UNiagaraEffectType EffectType

An effect types defines settings shared between systems, for example scalability and validation rules. Things like environment fx usually have a different effect type than gameplay relevant fx such as weapon impacts. This way whole classes of effects can be adjusted at once.

FixedBounds

FBox FixedBounds

The fixed bounding box value for the whole system. When placed in the level and the bounding box is not visible to the camera, the effect is culled from rendering.

FixedTickDeltaTime

float32 FixedTickDeltaTime

If activated, the system ticks with a fixed delta time instead of the varying game thread delta time. This leads to much more stable simulations. When the fixed tick delta is smaller than the game thread tick time the simulation is substepping by executing multiple ticks per frame. Note that activating this feature forces the system to tick on the game thread instead of an async task in parallel.

The max number of substeps per frame can be set via fx.Niagara.SystemSimulation.MaxTickSubsteps

ParameterCollectionOverrides

TArray<TObjectPtr<UNiagaraParameterCollectionInstance> > ParameterCollectionOverrides

Platforms

FNiagaraPlatformSet Platforms

RandomSeed

int RandomSeed

Seed used for system script random number generator.

SystemScalabilityOverrides

FNiagaraSystemScalabilityOverrides SystemScalabilityOverrides

TemplateAssetDescription

FText TemplateAssetDescription

TranslucencySortDistanceOffset

float32 TranslucencySortDistanceOffset

When enabled this is the default value set on the component. Modifies the sort distance for translucent objects, see PrimitiveComponent description for more details.

TranslucencySortPriority

int TranslucencySortPriority

When enabled this is the default value set on the component. Adjusts the translucent object sorting priority, see PrimitiveComponent description for more details.

WarmupTickCount

int WarmupTickCount

Number of ticks to process for warmup. You can set by this or by time via WarmupTime.

WarmupTickDelta

float32 WarmupTickDelta

Delta time to use for warmup ticks.

WarmupTime

float32 WarmupTime

Warm up time in seconds. Used to calculate WarmupTickCount. Rounds down to the nearest multiple of WarmupTickDelta.