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> Unreal Engine API Reference > Plugins > HairStrandsCore > UGroomAsset

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UGroomAsset

Implements an asset that can be used to store hair strands

Inheritance Hierarchy

UObjectBase

UObjectBaseUtility

UObject

UGroomAsset

References

Module	HairStrandsCore
Header	/Engine/Plugins/Runtime/HairStrands/Source/HairStrandsCore/Public/GroomAsset.h
Include	#include "GroomAsset.h"

Syntax

UCLASS(BlueprintType, AutoExpandCategories=("HairRendering", "HairPhysics", "HairInterpolation"),
       HideCategories=(Object, "Hidden"))
class UGroomAsset :
    public UObject,
    public IInterface_AssetUserData

Remarks

Implements an asset that can be used to store hair strands

Variables

	Name	Description
TObjectPtr< cla...	AssetImportData	Asset data to be used when re-importing
TArray< TObject...	AssetUserData	Array of user data stored with the asset
TArray< int32 >	DeformedGroupSections	Deformed skeletal mesh mapping from groups to sections
FPerPlatformBoo...	DisableBelowMinLodStripping	When true all LODs below MinLod will still be cooked
TArray< float >	EffectiveLODBias	The LOD bias to use after LOD stripping, regardless of MinLOD. Computed at cook time
bool	EnableGlobalInterpolation	Enable radial basis function interpolation to be used instead of the local skin rigid transform
TArray< FHairGr...	HairGroupsCards	Cards - Source description data
TArray< FHairGr...	HairGroupsData	Store strands/cards/meshes data
TArray< FHairGr...	HairGroupsInfo
TArray< FHairGr...	HairGroupsInterpolation
TArray< FHairGr...	HairGroupsLOD
TArray< FHairGr...	HairGroupsMaterials	Meshes - Source description data
TArray< FHairGr...	HairGroupsMeshes	Meshes - Source description data
TArray< FHairGr...	HairGroupsPhysics
TArray< FHairGr...	HairGroupsRendering
EGroomInterpola...	HairInterpolationType	Type of interpolation used
FPerPlatformInt	MinLOD	Minimum LOD to cook
FOnGroomAssetCh...	OnGroomAssetChanged	Private :
FOnGroomAssetRe...	OnGroomAssetResourcesChanged
FOnGroomAsyncLo...	OnGroomAsyncLoadFinished
TObjectPtr< USk...	RiggedSkeletalMesh	Deformed skeletal mesh that will drive the groom deformation/simulation.

Constructors

	Name	Description
	UGroomAsset ( const FObjectInitializer& ObjectIn... )

Functions

	Name	Description
bool	AreGroupsValid()
bool	BuildCardsGeometry()
bool	BuildMeshesGeometry()
bool	CacheCardsGeometry ( uint32 GroupIndex, const FString& StrandsKey )
bool	CacheDerivedData ( uint32 GroupIndex )	Caches the computed (group) groom data with the given build settings from/to the Derived Data Cache, building it if needed.
bool	CacheDerivedDatas()	Caches the computed (group) groom data with the given build settings from/to the Derived Data Cache, building it if needed.
bool	CacheMeshesGeometry ( uint32 GroupIndex )
bool	CacheStrandsData ( uint32 GroupIndex, FString& OutDerivedDataKey )
bool	CanRebuildFromDescription()	Returns true if the asset has the HairDescription needed to recompute its groom data
TArray< FHai...	CollectVertexFactoryTypesPerMaterialData ( EShaderPlatform ShaderPlatform )	Used for PSO precaching of used materials and vertex factories
void	CommitHairDescription ( FHairDescription&& HairDescription, EHairDescriptionType Type )	Commits a HairDescription to buffer for serialization
void	CreateDebugData()
uint8	GenerateClassStripFlags ( FArchive& Ar )
FName	GetAssetPathName ( int32 LODIndex )	Helper function to return the asset path name, optionally joined with the LOD index if LODIndex > -1.
EGroomBindin...	GetBindingType ( int32 GroupIndex, int32 LODIndex )
FString	GetDerivedDataKey()
FString	GetDerivedDataKeyForCards ( uint32 GroupIt, const FString& StrandsKey )
FString	GetDerivedDataKeyForMeshes ( uint32 GroupIndex )
FString	GetDerivedDataKeyForStrands ( uint32 GroupIndex )
EGroomGeomet...	GetGeometryType ( int32 GroupIndex, int32 LODIndex )
bool	GetHairCardsGuidesDatas ( const int32 GroupIndex, const int32 LODIndex, FHairStrandsDatas& OutCardsGuidesD... )
FHairDescrip...	GetHairDescription()
const FHairD...	GetHairDescriptionGroups()
bool	GetHairStrandsDatas ( const int32 GroupIndex, FHairStrandsDatas& OutStrandsData, FHairStrandsDatas& OutGuidesData )	Get/Build render & guides data based on the hair description and interpolation settings
int32	GetLODCount()
int32	GetMaterialIndex ( FName MaterialSlotName )	Return the material slot index corresponding to the material name
TArray< FNam...	GetMaterialSlotNames()
int32	GetNumHairGroups()
FOnGroomAsse...	GetOnGroomAssetChanged()
FOnGroomAsse...	GetOnGroomAssetResourcesChanged()
FOnGroomAsyn...	GetOnGroomAsyncLoadFinished()
bool	HasDebugData()	Debug data for derived asset generation (strands textures, ...).
bool	HasGeometryType ( uint32 GroupIndex, EGroomGeometryType Type )
bool	HasGeometryType ( EGroomGeometryType Type )
void	InitCardsResources()
void	InitGuideResources()
void	InitMeshesResources()
void	InitResources()	Initialize/Update/Release resources.
void	InitStrandsResources()
bool	IsDeformationEnable ( int32 GroupIndex )
bool	IsGlobalInterpolationEnable ( int32 GroupIndex, int32 LODIndex )
bool	IsMaterialSlotNameValid ( FName MaterialSlotName )
bool	IsMaterialUsed ( int32 MaterialIndex )
bool	IsSimulationEnable ( int32 GroupIndex, int32 LODIndex )
bool	IsSimulationEnable()
bool	IsValid()
bool	IsVisible ( int32 GroupIndex, int32 LODIndex )
void	MarkMaterialsHasChanged()
bool	NeedsInterpolationData()
bool	NeedsInterpolationData ( int32 GroupIndex )
void	ReleaseCardsResource ( uint32 GroupIndex )
void	ReleaseGuidesResource ( uint32 GroupIndex )
void	ReleaseMeshesResource ( uint32 GroupIndex )
void	ReleaseResource()
void	ReleaseStrandsResource ( uint32 GroupIndex )
void	SaveProceduralCards ( uint32 CardsGroupIndex )	Save out a static mesh based on generated cards.
void	SetHairWidth ( float Width )
void	SetNumGroup ( uint32 InGroupCount, bool bResetGroupData, bool bResetOtherData )
void	SetScatterSceneLighting ( bool Enable )
void	SetStableRasterization ( bool bEnable )	Helper functions for setting options on all hair groups.
void	StripLODs ( const TArray< int32 >& LODsToKeep, bool bRebuildResources )
void	UpdateCachedSettings()
void	UpdateHairGroupsInfo()
void	UpdateResource()

Overridden from UObject

	Name	Description
void	BeginDestroy()	Called before destroying the object.
void	GetAssetRegistryTags ( TArray< FAssetRegistryTag >& OutTa... )	Retrievde the asset tags
void	GetResourceSizeEx ( FResourceSizeEx& CumulativeResourc... )	Get the size of the object/resource for use in memory tools or to display to artists/LDs in the Editor This is the extended version which separates up the used memory into different memory regions (the actual definition of which may be platform specific).
void	PostEditChangeProperty ( FPropertyChangedEvent& PropertyCha... )	Part of Uobject interface
void	PostInitProperties()	Part of Uobject interface
void	PostLoad()	Do any object-specific cleanup required immediately after loading an object.
void	PreSave ( FObjectPreSaveContext SaveContext )	Presave function.
void	Serialize ( FArchive& Ar )	Handles reading, writing, and reference collecting using FArchive.

Overridden from IInterface_AssetUserData

		Name	Description
	void	AddAssetUserData ( UAssetUserData* InUserData )
	const TArray...	GetAssetUserDataArray()
	UAssetUserDa...	GetAssetUserDataOfClass ( TSubclassOf< UAssetUserData > InUse... )
	void	RemoveUserDataOfClass ( TSubclassOf< UAssetUserData > InUse... )

Enums

	Name	Description
	EClassDataStripFlag
	EHairDescriptionType

Typedefs

Name	Description
FOnGroomAssetChanged	Notification when anything changed
FOnGroomAssetResourcesChanged
FOnGroomAsyncLoadFinished

Deprecated Functions

		Name	Description
	PRAGMA_DISAB...	PreSave ( const ITargetPlatform* TargetP... )	Use version that takes FObjectPreSaveContext instead.

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