UNiagaraDataInterfaceDataChannelRead Class Reference

Static Public Member Functions
Static Functions
static UClass	StaticClass ()
Static Public Member Functions inherited from UNiagaraDataInterfaceRWBase
static UClass	StaticClass ()
Static Public Member Functions inherited from UNiagaraDataInterface
static UClass	StaticClass ()

Public Attributes
Data Channel
bool	bReadCurrentFrame
	True if this reader will read the current frame's data. If false, we read the previous frame. Reading the current frame introduces a tick order dependency but allows for zero latency reads. Any data channel elements that are generated after this reader is used are missed. Reading the previous frame's data introduces a frame of latency but ensures we never miss any data as we have access to the whole frame.
bool	bUpdateSourceDataEveryTick
	Whether this DI should request updated source data from the Data Channel each tick. Some Data Channels have multiple separate source data elements for things such as spatial subdivision. Each DI will request the correct one for it's owning system instance from the data channel. Depending on the data channel this could be an expensive search so we should avoid doing this every tick if possible.
UNiagaraDataChannelAsset	Channel
	The data channel to access and read from.
Spawning
bool	bOverrideSpawnGroupToDataChannelIndex
	When true, Emitter.Spawn group for any spawned particles will be overridden to the index of the data channel element that generated that spawn. Doing this will submit all NDC spawns individually and will be less performant. However it will allow particles to access the NDC data that generated then via the SpawnGroup value. It will also mean that Exec Index will be correct on a per NDC Entry level. Without this settings ExecIndex will be 0...TotalSpawnCount-1. With this it will be 0...SpawnCount for each NDC item individually. Unless absolutely needed this is discouraged as it comes at significant performance cost when spawning and GPU emitters can currently only handle 8 individual spawns per frame. Calling GetNDCSpawnInfo() in the particle spawn script to get the spawning NDC Index is prefered.

Member Function Documentation

StaticClass()

UClass StaticClass ( )

static

Member Data Documentation

bOverrideSpawnGroupToDataChannelIndex

bool bOverrideSpawnGroupToDataChannelIndex

When true, Emitter.Spawn group for any spawned particles will be overridden to the index of the data channel element that generated that spawn. Doing this will submit all NDC spawns individually and will be less performant. However it will allow particles to access the NDC data that generated then via the SpawnGroup value. It will also mean that Exec Index will be correct on a per NDC Entry level. Without this settings ExecIndex will be 0...TotalSpawnCount-1. With this it will be 0...SpawnCount for each NDC item individually. Unless absolutely needed this is discouraged as it comes at significant performance cost when spawning and GPU emitters can currently only handle 8 individual spawns per frame. Calling GetNDCSpawnInfo() in the particle spawn script to get the spawning NDC Index is prefered.

bReadCurrentFrame

bool bReadCurrentFrame

True if this reader will read the current frame's data. If false, we read the previous frame. Reading the current frame introduces a tick order dependency but allows for zero latency reads. Any data channel elements that are generated after this reader is used are missed. Reading the previous frame's data introduces a frame of latency but ensures we never miss any data as we have access to the whole frame.

bUpdateSourceDataEveryTick

bool bUpdateSourceDataEveryTick

Whether this DI should request updated source data from the Data Channel each tick. Some Data Channels have multiple separate source data elements for things such as spatial subdivision. Each DI will request the correct one for it's owning system instance from the data channel. Depending on the data channel this could be an expensive search so we should avoid doing this every tick if possible.

Channel

UNiagaraDataChannelAsset Channel

The data channel to access and read from.