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  3. FNiagaraSystemSimulation

FNiagaraSystemSimulation

Simulation performing all system and emitter scripts for a instances of a [UNiagaraSystem](API\Plugins\Niagara\UNiagaraSystem) in a world.

Unreal Engine C++ API Reference > Plugins > Niagara

Inheritance Hierarchy

References

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

Syntax

class FNiagaraSystemSimulation : public TSharedFromThis< FNiagaraSystemSimulation, ESPMode::ThreadSafe >

Remarks

Simulation performing all system and emitter scripts for a instances of a UNiagaraSystem in a world.

Variables

  Type Name Description
Protected variable FGraphEventRef AllWorkCompleteGraphEvent Event to track all work is complete, i.e. System Concurrent, Instance Concurrent, Finalize
Protected variable uint32: 1 bBindingsInitialized  
Protected variable uint32: 1 bCanExecute  
Protected variable uint32: 1 bInSpawnPhase  
Protected variable uint32: 1 bIsSolo  
Protected variable FGraphEventRef ConcurrentTickGraphEvent Event to track the system simulation async tick is complete.
Protected variable FString CrashReporterTag  
Protected variable TArray< TArray< FNiagaraParameterStoreToDataSetBinding > > DataSetToEmitterEventParameters Binding to push system attributes into each emitter event parameters.
Protected variable TArray< FNiagaraParameterStoreToDataSetBinding > DataSetToEmitterGPUParameters Binding to push system attributes into each emitter gpu parameters.
Protected variable TArray< FNiagaraParameterStoreToDataSetBinding > DataSetToEmitterRendererParameters Binding to push system attributes into each emitter renderer parameters.
Protected variable TArray< FNiagaraParameterStoreToDataSetBinding > DataSetToEmitterSpawnParameters Binding to push system attributes into each emitter spawn parameters.
Protected variable TArray< FNiagaraParameterStoreToDataSetBinding > DataSetToEmitterUpdateParameters Binding to push system attributes into each emitter update parameters.
Protected variable FNiagaraGpuComputeDispatchInterface * DispatchInterface  
Protected variable TWeakObjectPtr< UNiagaraEffectType > EffectType We cache off the effect type in the unlikely even that someone GCs the System from under us so that we can keep the effect types instance count etc accurate.
Protected variable float FixedDeltaTickAge  
Protected variable FNiagaraDataSet MainDataSet Data set for the Running instance state.
Protected variable TOptional< float > MaxDeltaTime  
Protected variable FNiagaraDataSet PausedDataSet Data set for the Paused instance state.
Protected variable TArray< FNiagaraSystemInstance * > PendingTickGroupPromotions List of instances that are pending a tick group promotion.
Protected variable TUniquePtr< FNiagaraScriptExecutionContextBase > SpawnExecContext  
Protected variable FNiagaraParameterDirectBinding< float > SpawnGlobalSpawnCountScaleParam  
Protected variable FNiagaraParameterDirectBinding< float > SpawnGlobalSystemCountScaleParam  
Protected variable FNiagaraDataSet SpawningDataSet Data set for the Spawning instance state.
Protected variable FNiagaraDataSet SpawnInstanceParameterDataSet As there's a 1 to 1 relationship between system instance and their execution in this simulation we must pull all that instances parameters into a dataset for simulation.
Protected variable FNiagaraParameterStoreToDataSetBinding SpawnInstanceParameterToDataSetBinding Bindings that pull per component parameters into the spawn parameter dataset.
Protected variable FNiagaraParameterDirectBinding< int32 > SpawnNumSystemInstancesParam Direct bindings for Engine variables in System Spawn and Update scripts.
Protected variable UNiagaraSystem * System System of instances being simulated.
Protected variable TArray< FNiagaraSystemInstance * >[int32(ENiagaraSystemInstanceState::Num)] SystemInstancesPerState System instance per state.
Protected variable ETickingGroup SystemTickGroup Which tick group we are in, only valid when not in Solo mode.
Protected variable FNiagaraSystemTickBatch TickBatch Current tick batch we're filling ready for processing, potentially in an async task.
Protected variable FNiagaraTickInfo TickInfo  
Protected variable TUniquePtr< FNiagaraScriptExecutionContextBase > UpdateExecContext  
Protected variable FNiagaraParameterDirectBinding< float > UpdateGlobalSpawnCountScaleParam  
Protected variable FNiagaraParameterDirectBinding< float > UpdateGlobalSystemCountScaleParam  
Protected variable FNiagaraDataSet UpdateInstanceParameterDataSet  
Protected variable FNiagaraParameterStoreToDataSetBinding UpdateInstanceParameterToDataSetBinding Bindings that pull per component parameters into the update parameter dataset.
Protected variable FNiagaraParameterDirectBinding< int32 > UpdateNumSystemInstancesParam  
Protected variable UWorld * World World this system simulation belongs to.

Constructors

  Type Name Description
Public function    

Destructors

  Type Name Description
Public function    

Functions

  Type Name Description
Public function void  
Protected function void  
Public function void  
Public function void  
Protected function Const void Builds the constant buffer table for a given script execution
Public function void

Destroy ()

  
Public function Const void  
Protected function void  
Public function void Dump information about all instances tick
Protected function void  
Public function Const const FString &  
Public function Const FNiagaraGpuComputeDispatchInterface *  
Public function Const ENiagaraGPUTickHandlingMode  
Public function Const bool  
Public function UNiagaraParameterCollectionInstance *  
Public function FNiagaraScriptExecutionContextBase *  
Public function Const UNiagaraSystem *  
Protected function TArray< FNiagaraSystemInstance * > &  
Public function Const ETickingGroup  
Public function const FNiagaraTickInfo &  
Public function FNiagaraScriptExecutionContextBase *  
Public function Const UWorld *  
Public function bool

Init ( UNiagaraSystem* InSystem,
UWorld* InWorld,
bool bInIsSolo,
ETickingGroup TickGroup
)

  
Protected function void  
Public function Const bool

IsValid ()

  
Public function void  
Protected function void Does any prep work for system simulation such as pulling instance parameters into a dataset.
Public function void  
Public function void  
Public function void  
Protected function void

SetupParameters_GameThread ( float DeltaSeconds
)

 Sets constant parameter values
Public function void

SimCachePostTick_Concurrent ( float DeltaSeconds,
const FGraphEventRef& MyCompletionGraphEvent
)

 Called after the sim cache has been read.
Public function void Spawn any pending instances
Public function void

Spawn_GameThread ( float DeltaSeconds,
bool bPostActorTick
)

 Spawn any pending instances, assumes that you have update tick groups ahead of time.
Protected function void Runs the system spawn script for new system instances.
Public function void Second phase of system sim tick that can run on any thread.
Public function void

Tick_GameThread ( float DeltaSeconds,
const FGraphEventRef& MyCompletionGraphEvent
)

 First phase of system sim tick. Must run on GameThread.
Protected function void

Tick_GameThread_Internal ( float DeltaSeconds,
const FGraphEventRef& MyCompletionGraphEvent
)

  
Public function void Transfers a system instance from the current simulation into this one.
Protected function void Transfers the results of the system simulation into the emitter instances.
Public function void  
Protected function void Runs the system update script.
Public function void Update TickGroups for pending instances and execute tick group promotions.
Public function void

WaitForConcurrentTickComplete ( bool bEnsureComplete
)

 Wait for system simulation concurrent tick to complete.
Public function void

WaitForInstancesTickComplete ( bool bEnsureComplete
)

 Wait for system instances concurrent tick to complete.

Constants

Name Description
bUseLegacyExecContexts  

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