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> Unreal Engine API Reference > Runtime > Engine > FParticleAnimTrailEmitterInstance

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FParticleAnimTrailEmitterInstance

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Inheritance Hierarchy

FParticleEmitterInstance

FParticleTrailsEmitterInstance_Base

FParticleAnimTrailEmitterInstance

References

Module	Engine
Header	/Engine/Source/Runtime/Engine/Public/ParticleEmitterInstances.h
Include	#include "ParticleEmitterInstances.h"

Syntax

struct FParticleAnimTrailEmitterInstance : public FParticleTrailsEmitterInstance_Base

Variables

	Name	Description
uint32: 1	bRenderGeometry	Editor only variables controlling the debug rendering for trails.
uint32: 1	bRenderSpawnPoints
uint32: 1	bRenderTangents
uint32: 1	bRenderTessellation
bool	bTagTrailAsDead	When set, the current trail will be marked as dead in the next tick.
bool	bTrailEnabled	Whether new particles should be spawned.
FName	FirstSocketName	The name of the socket that supplies the first edge for this emitter.
int32	HeadOnlyParticles	The number of particles in the trail which are either marked
const void *...	Owner	The owner of this trail.
FName	SecondSocketName	The name of the socket that supplies the second edge for this emitter.
UParticleModule...	SpawnPerUnitModule	SpawnPerUnit module (hijacking it for trails here)
UParticleModule...	TrailTypeData	The TypeData module for this trail emitter
float	Width	The width of the trail.
ETrailWidthMode	WidthMode	How the width is applied to the trail.

Constructors

	Name	Description
	FParticleAnimTrailEmitterInstance()	Constructor

Destructors

	Name	Description
	~FParticleAnimTrailEmitterInstance()	Destructor

Functions

	Name	Description
void	DetermineVertexAndTriangleCount()	Determine the number of vertices and triangles in each trail
bool	GetSpawnPerUnitAmount ( float DeltaTime, int32 InTrailIdx, int32& OutCount, float& OutRate )
bool	IsTrailActive()
void	RecalculateTangentAndInterpolationParam ( FBaseParticle* PrevParticle, FAnimTrailTypeDataPayload* Pre..., FBaseParticle* CurrParticle, FAnimTrailTypeDataPayload* Cur..., FBaseParticle* NextParticle, FAnimTrailTypeDataPayload* Nex... )	Helper function for recalculating tangents and the spline interpolation parameter...
void	ResolveSource()
void	SetTrailDebugData ( bool bInRenderGeometry, bool bInRenderSpawnPoints, bool bInRenderTessellation, bool bInRenderTangents )	Sets various debug variables for trails.
void	SpawnParticle ( int32& StartParticleIndex, const FAnimTrailParticleSpawnParams... )	Helper to spawn a trail particle during SpawnParticles().

Overridden from FParticleTrailsEmitterInstance_Base

	Name	Description
void	PrintAllActiveParticles()	Prints out info for all active particles.
void	PrintParticleData ( FBaseParticle* Particle, FTrailsBaseTypeDataPayload* Tr..., int32 CurrentIndex, int32 TrailIndex )	Prints out info for a single particle.
void	PrintTrails()	Traverses all trails and prints out debugging info.
void	SetupTrailModules()
void	Tick_RecalculateTangents ( float DeltaTime, UParticleLODLevel* CurrentLODL... )	Tick sub-function that handles recalculation of tangents
void	UpdateSourceData ( float DeltaTime, bool bFirstTime )

Overridden from FParticleEmitterInstance

	Name	Description
void	BeginTrail()	Begins the trail.
void	EndTrail()	Ends the trail.
bool	FillReplayData ( FDynamicEmitterReplayDataBase& Out... )	Captures dynamic replay data for this particle system.
void	ForceUpdateBoundingBox()	Force the bounding box to be updated.
void	GetAllocatedSize ( int32& OutNum, int32& OutMax )	Retrieve the allocated size of this instance.
FDynamicEmit...	GetDynamicData ( bool bSelected, ERHIFeatureLevel::Type InFeatureLev... )	Retrieves the dynamic data for the emitter
FDynamicEmit...	GetReplayData()	Retrieves replay data for the emitter
void	GetResourceSizeEx ( FResourceSizeEx& CumulativeResourc... )	Returns the size of the object/ resource for display to artists/ LDs in the Editor.
bool	HasCompleted()	Has the instance completed it's run?
void	InitParameters ( UParticleEmitter* InTemplate, UParticleSystemComponent* InCo... )
bool	IsTrailEmitter()
void	SetTrailSourceData ( FName InFirstSocketName, FName InSecondSocketName, ETrailWidthMode InWidthMode, float InWidth )	Sets the date that defines this trail.
float	Spawn ( float DeltaTime )	Spawn particles for this emitter instance
void	UpdateBoundingBox ( float DeltaTime )	Update the bounding box for the emitter