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  3. TPreAnimatedStateStorage

TPreAnimatedStateStorage

Storage container for a specific type of pre-animated state as defined by the specified traits.

API > API/Runtime > API/Runtime/MovieScene > API/Runtime/MovieScene/Evaluation > API/Runtime/MovieScene/Evaluation/PreAnimatedState

Inheritance Hierarchy

References

   
Module MovieScene
Header /Engine/Source/Runtime/MovieScene/Public/Evaluation/PreAnimatedState/MovieScenePreAnimatedStateStorage.h
Include #include "Evaluation/PreAnimatedState/MovieScenePreAnimatedStateStorage.h"

Syntax

template<typename StorageTraits>  
struct TPreAnimatedStateStorage : public UE::MovieScene::IPreAnimatedStorage

Remarks

Storage container for a specific type of pre-animated state as defined by the specified traits.

Reference collection for KeyType and StorageType is automatically provided by way of an optional AddReferencedObjectForComponent override

Traits must include a type definition or using alias for its KeyType and StorageType, defining the type of key to use for associating the pre-animated value and the storage value type respectively.

Additionally, traits must define a RestorePreAnimatedValue function that will be used by the storage container to restore data back to its previous value.

An example trait that maps an object and a name identifier to a string would look like this: struct FExampleTraits { using KeyType = TTuple; using StorageType = FString;

static void RestorePreAnimatedValue(const KeyType& InKey, const FString& PreviousString, const FRestoreStateParams& Params) { if (UMyObjectType* Object = Cast(InKey.Get<0>().ResolveObjectPtr())) { Object->SetStringValue(InKey.Get<1>(), PreviousString); } } }

Furthermore, if the CachePreAnimatedValuesTask is used, traits must implement a CachePreAnimatedValue function that receives the contributor component types, and returns the cached value:

static FString CachePreAnimatedValue(UObject* InObject, const FName& StringName) { UMyObjectType* Object = CastChecked(InObject); return Object->GetStringValue(StringName); }

Traits may be stateful if desired. Stateful traits must be provided to the constructor in order to be valid.

Variables

  Type Name Description
Protected variable TMap< KeyType, FPreAnimatedStorageIndex > KeyToStorageIndex Map that associates a storage index with a key.
Protected variable FPreAnimatedStateExtension * ParentExtension Pointer to our parent extension
Protected variable TSparseArray< FCachedData > PreAnimatedStorage Sparse array of cached data that represents persistent, or both persistent and transient storage (but never exclusively transient storage).
Protected variable const IRestoreMask * RestoreMask Temporary restoration mask
Protected variable FPreAnimatedStorageID StorageID Our storage ID
Protected variable StorageTraits Traits Traits instance - normally not required but some traits require state
Protected variable TSortedMap< FPreAnimatedStorageIndex, StorageType > TransientPreAnimatedStorage Storage that holds values that need to be kept transiently (for evaluation).

Constructors

  Type Name Description
Public function    
Public function  

TPreAnimatedStateStorage ( StorageTraits&& InTraits
)

  
Public function   Pre-Animated storage is not copyable

Functions

  Type Name Description
Public function void Assign the value for a specific storage index. It is an error to re-assign an already cached value.
Public function void

BeginTrackingAndCachePreAnimatedValues ( UMovieSceneEntitySystemLinker* Linker,
TComponentTypeID< ContributorTypes >... InComponentTypes
)

 Look at any entity with the specified component types, and set up new associations with storage indices for those entities, whilst also caching pre-animated values at the same time.
Public function void

BeginTrackingAndCachePreAnimatedValuesTask ( UMovieSceneEntitySystemLinker* Linker,
const TaskType& InParams,
TComponentTypeID< ContributorTypes >... InComponentTypes
)

 Look at any entity with the specified component types, and set up new associations with storage indices for those entities, whilst also caching pre-animated values at the same time.
Public function void

BeginTrackingEntities ( UMovieSceneEntitySystemLinker* Linker,
TComponentTypeID< ContributorTypes >... InComponentTypes
)

 Look at any entity with the specified component types, and set up new associations with storage indices for those entities The provided component values are put together to make up the storage key WARNING: Does not cache actual pre-animated values
Public function void

BeginTrackingEntitiesTask ( UMovieSceneEntitySystemLinker* Linker,
const TaskType& InParams,
TComponentTypeID< ContributorTypes >... InComponentTypes
)

 Look at any entity with the specified component types, and set up new associations with storage indices for those entities The provided component values are put together to make up the storage key WARNING: Does not cache actual pre-animated values
Public function void

BeginTrackingEntity ( FMovieSceneEntityID EntityID,
const bool bWantsRestoreState,
FRootInstanceHandle RootInstanceHandle,
ContributorTypes... InComponents
)

 Set up a new associations with a storage index for the given entity The provided component values are put together to make up the storage key WARNING: Does not cache actual pre-animated values
Public function void

CachePreAnimatedValue ( FPreAnimatedStorageGroupHandle GroupHandle,
const KeyType& InKey,
OnCacheValue&& CacheCallback,
EPreAnimatedCaptureSourceTracking TrackingMode
)

 Save pre-animated state for the specified group and key using a callback.
Public function void

CachePreAnimatedValue ( const KeyType& InKey,
OnCacheValue&& CacheCallback,
EPreAnimatedCaptureSourceTracking TrackingMode
)

 Save pre-animated state for the specified group and key using a callback.
Public function void

CachePreAnimatedValue ( ContributorTypes... Values
)

 Save pre-animated state for the specified values, using CacheIfTracked tracking Requires that the traits class implements CachePreAnimatedValue(ContributorTypes...)
Public function void

CachePreAnimatedValues ( UMovieSceneEntitySystemLinker* Linker,
TComponentTypeID< ContributorTypes >... InComponentTypes
)

 Cache pre-animated values for entities with the specified component types
Public function void

CachePreAnimatedValuesTask ( UMovieSceneEntitySystemLinker* Linker,
const TaskType& InParams,
TComponentTypeID< ContributorTypes >... InComponentTypes
)

 Cache pre-animated values for entities with the specified component types
Public function void

CacheTrackedPreAnimatedValue ( EPreAnimatedCaptureSourceTracking TrackingMode,
ContributorTypes... Values
)

 Save pre-animated state for the specified values Requires that the traits class implements CachePreAnimatedValue(ContributorTypes...)
Public function FPreAnimatedStateEntry

FindEntry ( KeyArgs&&... InKeyArgs
)

 Given a list of arguments suitable for building a storage key, builds that key, and then tries to find an existing pre-animated state entry for that key if it already exists.
Public function Const FPreAnimatedStorageIndex

FindStorageIndex ( const KeyType& InKey
)

 Attempt to find a storage index for the specified key
Public function void Cause a previously cached value to always outlive any actively animating sources.
Public function Const const StorageType & Get the cached value associated with a particular storage index
Public function Const const KeyType &

GetKey ( FPreAnimatedStorageIndex StorageIndex
)

 Get the key associated with a particular storage index
Public function FPreAnimatedStorageIndex

GetOrCreateStorageIndex ( const KeyType& InKey
)

 Attempt to find a storage index for the specified key, creating a new one if it doesn't exist
Public function Const bool Check whether we have ever animated the specified storage index.
Public function Const bool Check whether a piece of cached storage has been initialized yet.
Public function Const bool Check whether the storage for a given index and requirement has already been initialized
Public function FPreAnimatedStateEntry

MakeEntry ( KeyArgs&&... InKeyArgs
)

 Creates a new pre-animated state entry from a list of arguments suitable for building the storage key.
Public function void

ReplaceKey ( FPreAnimatedStorageIndex StorageIndex,
const KeyType& NewKey
)

 Replace the key associated with a particular storage index
Public function void

SetRestoreMask ( const IRestoreMask* InRestoreMask
)

 Called prior to restoring pre-animated state to control whether this storage should restore state or not
Protected function bool

ShouldTrackCaptureSource ( EPreAnimatedCaptureSourceTracking TrackingMode,
KeyArgs&&... InKeyArgs
)

  
Protected function void Begins tracking the current entry with the currently set tracking source, if necessary/desirable.

Overridden from IPreAnimatedStorage

  Type Name Description
Public function Virtual void

AddReferencedObjects ( FReferenceCollector& ReferenceCollector
)

 Called by the owning extension to add reference collection tracking for pre-animated state
Public function Virtual EPreAnimatedStorageRequirement Discard a specified index within this storage container.
Public function Virtual Const FPreAnimatedStorageID Retrieve the ID that uniquely identifies this storage container
Public function Virtual void

Initialize ( FPreAnimatedStorageID InStorageID,
FPreAnimatedStateExtension* InParentExtension
)

 Called when this storage is created inside the pre-animated state extension on a UMovieSceneEntitySystemLinker
Public function Virtual void

OnObjectReplaced ( FPreAnimatedStorageIndex StorageIndex,
const FObjectKey& OldObject,
const FObjectKey& NewObject
)

  
Public function Virtual EPreAnimatedStorageRequirement Restore a specified index within this storage container.

Operators

  Type Name Description
Public function TPreAnimatedStateStorage &  

Classes

  Type Name Description
Protected struct FCachedData    
Public struct IRestoreMask Interface used for restoring pre-animated state that allows an external system to control whether state should be restored or not  

Typedefs

Name Description
KeyType The key type to use as a key in the map that associates pre-animated state values to owners (ie, an object and property name)
StorageType The value type this storage should store (ie, the actual property type)

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