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  3. FMassEntityManager

FMassEntityManager

The type responsible for hosting Entities managing Archetypes.

API > API/Runtime > API/Runtime/MassEntity

Inheritance Hierarchy

  • TSharedFromThis< FMassEntityManager >
  • FGCObject
  • FMassEntityManager

References

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

Syntax

struct FMassEntityManager :  
    public TSharedFromThis< FMassEntityManager >,  
    public FGCObject

Remarks

The type responsible for hosting Entities managing Archetypes. Entities are stored as FEntityData entries in a chunked array. Each valid entity is assigned to an Archetype that stored fragments associated with a given entity at the moment.

FMassEntityManager supplies API for entity creation (that can result in archetype creation) and entity manipulation. Even though synchronized manipulation methods are available in most cases the entity operations are performed via a command buffer. The default command buffer can be obtained with a Defer() call. FMassEntityManager are meant to be stored with a TSharedPtr or TSharedRef. Some of Mass API pass around FMassEntityManager& but programmers can always use AsShared() call to obtain a shared ref for a given manager instance (as supplied by deriving from TSharedFromThis). IMPORTANT: if you create your own FMassEntityManager instance remember to call Initialize() before using it.

Variables

  Type Name Description
Public variable friend FMassDebugger  
Public variable friend FMassEntityQuery  

Constructors

  Type Name Description
Public function  

FMassEntityManager ( UObject* InOwner
)

  
Public function    

Destructors

  Type Name Description
Public function Virtual    

Functions

  Type Name Description
Public function void Adds fragments and tags indicated by InOutDescriptor to the Entity.
Public function bool

AddConstSharedFragmentToEntity ( const FMassEntityHandle Entity,
const FConstSharedStruct& InConstSharedFragment
)

 Adds a new const shared fragment to the given entity.
Public function void

AddFragmentInstanceListToEntity ( FMassEntityHandle Entity,
TConstArrayView< FInstancedStruct > FragmentInstanceList
)

  
Public function void

AddFragmentListToEntity ( FMassEntityHandle Entity,
TConstArrayView< const UScriptStruct* > FragmentList
)

 Ensures that only unique fragments are added.
Public function void

AddFragmentToEntity ( FMassEntityHandle Entity,
const UScriptStruct* FragmentType
)

  
Public function void

AddFragmentToEntity ( FMassEntityHandle Entity,
const UScriptStruct* FragmentType,
const FStructInitializationCallback& Initializer
)

  
Public function Virtual void

AddReferencedObjects ( FReferenceCollector& Collector
)

  
Public function void

AddTagToEntity ( FMassEntityHandle Entity,
const UScriptStruct* TagType
)

  
Public function void

AppendCommands ( TSharedPtr< FMassCommandBuffer >& InOutCommandBuffer
)

 Depending on the current state of Manager's command buffer the function will either move all the commands out of InOutCommandBuffer into the main command buffer or append it to the list of command buffers waiting to be flushed.
Public function void

BatchAddFragmentInstancesForEntities ( TConstArrayView< FMassArchetypeEntityCollectionWithPayload > EntityCollections,
const FMassFragmentBitSet& FragmentsAffected
)

  
Public function void

BatchAddSharedFragmentsForEntities ( TConstArrayView< FMassArchetypeEntityCollection > EntityCollections,
const FMassArchetypeSharedFragmentValues& AddedFragmentValues
)

 Adds a new const and non-const shared fragments to all entities provided via EntityCollections
Public function TSharedRef< FEntityCreationContext >

BatchBuildEntities ( const FMassArchetypeEntityCollectionWithPayload& EncodedEntitiesWithPayload,
FMassArchetypeCompositionDescriptor&& Composition,
const FMassArchetypeSharedFragmentValues& SharedFragmentValues,
const FMassArchetypeCreationParams& CreationParams
)

  
Public function TSharedRef< FEntityCreationContext >

BatchBuildEntities ( const FMassArchetypeEntityCollectionWithPayload& EncodedEntitiesWithPayload,
const FMassFragmentBitSet& FragmentsAffected,
const FMassArchetypeSharedFragmentValues& SharedFragmentValues,
const FMassArchetypeCreationParams& CreationParams
)

  
Public function void

BatchChangeFragmentCompositionForEntities ( TConstArrayView< FMassArchetypeEntityCollection > EntityCollections,
const FMassFragmentBitSet& FragmentsToAdd,
const FMassFragmentBitSet& FragmentsToRemove
)

  
Public function void

BatchChangeTagsForEntities ( TConstArrayView< FMassArchetypeEntityCollection > EntityCollections,
const FMassTagBitSet& TagsToAdd,
const FMassTagBitSet& TagsToRemove
)

  
Public function TSharedRef< FEntityCreationContext >

BatchCreateEntities ( const FMassArchetypeHandle& ArchetypeHandle,
const int32 Count,
TArray< FMassEntityHandle >& InOutEntities
)

  
Public function TSharedRef< FEntityCreationContext >

BatchCreateEntities ( const FMassArchetypeHandle& ArchetypeHandle,
const FMassArchetypeSharedFragmentValues& SharedFragmentValues,
const int32 Count,
TArray< FMassEntityHandle >& InOutEntities
)

 A version of CreateEntity that's creating a number of entities (Count) in one go
Public function TSharedRef< FEntityCreationContext >

BatchCreateReservedEntities ( const FMassArchetypeHandle& ArchetypeHandle,
const FMassArchetypeSharedFragmentValues& SharedFragmentValues,
TConstArrayView< FMassEntityHandle > ReservedEntities
)

 A version of CreateEntity that's creating a number of entities (Count) in one go
Public function TSharedRef< FEntityCreationContext >

BatchCreateReservedEntities ( const FMassArchetypeHandle& ArchetypeHandle,
TConstArrayView< FMassEntityHandle > OutEntities
)

  
Public function void

BatchDestroyEntities ( TConstArrayView< FMassEntityHandle > InEntities
)

 Destroys all the entities in the provided array of entities.
Public function void

BatchDestroyEntityChunks ( TConstArrayView< FMassArchetypeEntityCollection > Collections
)

  
Public function void Destroys all the entities provided via the Collection.
Public function TConstArrayView< FMassEntityHandle >

BatchReserveEntities ( const int32 Count,
TArray< FMassEntityHandle >& InOutEntities
)

 Reserves Count number of entities and appends them to InOutEntities
Public function int32 Reserves number of entities corresponding to number of entries in the provided array view InOutEntities.
Public function Static void

BatchSetEntityFragmentsValues ( TConstArrayView< FMassArchetypeEntityCollection > EntityCollections,
TArrayView< const FInstancedStruct > FragmentInstanceList
)

  
Public function Static void

BatchSetEntityFragmentsValues ( const FMassArchetypeEntityCollection& SparseEntities,
TArrayView< const FInstancedStruct > FragmentInstanceList
)

 Copies values from FragmentInstanceList over to fragments of given entities collection.
Public function void

BuildEntity ( FMassEntityHandle Entity,
TConstArrayView< FInstancedStruct > FragmentInstanceList,
const FMassArchetypeSharedFragmentValues& SharedFragmentValues
)

 Builds an entity for it to be ready to be used by the subsystem
Public function void

BuildEntity ( FMassEntityHandle Entity,
const FMassArchetypeHandle& ArchetypeHandle,
const FMassArchetypeSharedFragmentValues& SharedFragmentValues
)

 Builds an entity for it to be ready to be used by the subsystem
Public function Const void Asserts that IsEntityBuilt.
Public function Const void Asserts that IsEntityValid.
Public function FMassArchetypeHandle CreateArchetype from a composition descriptor and initial values
Public function FMassArchetypeHandle

CreateArchetype ( FMassArchetypeHandle SourceArchetype,
TConstArrayView< const UScriptStruct* > FragmentsAndTagsList
)

 A special, relaxed but slower version of CreateArchetype functions that allows FragmentAngTagsList to contain both fragments and tags.
Public function FMassArchetypeHandle

CreateArchetype ( const TSharedPtr< FMassArchetypeData >& SourceArchetype,
const FMassFragmentBitSet& InFragments
)

 Creates an archetype like SourceArchetype + InFragments.
Public function FMassArchetypeHandle

CreateArchetype ( FMassArchetypeHandle SourceArchetype,
TConstArrayView< const UScriptStruct* > FragmentsAndTagsList,
const FMassArchetypeCreationParams& CreationParams
)

 A special, relaxed but slower version of CreateArchetype functions that allows FragmentAngTagsList to contain both fragments and tags.
Public function FMassArchetypeHandle

CreateArchetype ( const TSharedPtr< FMassArchetypeData >& SourceArchetype,
const FMassFragmentBitSet& InFragments,
const FMassArchetypeCreationParams& CreationParams
)

 Creates an archetype like SourceArchetype + InFragments.
Public function FMassArchetypeHandle

CreateArchetype ( TConstArrayView< const UScriptStruct* > FragmentsAndTagsList,
const FMassArchetypeCreationParams& CreationParams
)

 A special, relaxed but slower version of CreateArchetype functions that allows FragmentAngTagsList to contain both fragments and tags.
Public function FMassEntityHandle

CreateEntity ( const FMassArchetypeHandle& ArchetypeHandle,
const FMassArchetypeSharedFragmentValues& SharedFragmentValues
)

 Creates fully built entity ready to be used by the subsystem
Public function FMassEntityHandle

CreateEntity ( TConstArrayView< FInstancedStruct > FragmentInstanceList,
const FMassArchetypeSharedFragmentValues& SharedFragmentValues,
const FMassArchetypeCreationParams& CreationParams
)

 Creates fully built entity ready to be used by the subsystem
Public function FMassExecutionContext

CreateExecutionContext ( const float DeltaSeconds
)

 Creates and initializes a FMassExecutionContext instance.
Public function Const FMassCommandBuffer &

Defer ()

  
Public function void  
Public function void Destroys a fully built entity, use ReleaseReservedEntity if entity was not yet built.
Public function void

DoEntityCompaction ( const double TimeAllowed
)

 Go through all archetypes and compact entities
Public function void  
Public function void

FlushCommands ( TSharedPtr< FMassCommandBuffer >& InCommandBuffer
)

  
Public function Static void

ForEachArchetypeFragmentType ( const FMassArchetypeHandle& ArchetypeHandle,
TFunction< void(const UScriptStruct*)> Function
)

 Method to iterate on all the fragment types of an archetype
Public function void

ForEachSharedFragment ( TFunctionRef< void(T&) > ExecuteFunction
)

  
Public function void

ForEachSharedFragmentConditional ( TFunctionRef< bool(T&) > ConditionFunction,
TFunctionRef< void(T&) > ExecuteFunction
)

  
Public function Const const FMassArchetypeCompositionDescriptor &

GetArchetypeComposition ( const FMassArchetypeHandle& ArchetypeHandle
)

  
Public function Const uint32  
Public function Const FMassArchetypeHandle Fetches the archetype for a given Entity.
Public function Const FMassArchetypeHandle Fetches the archetype for a given Entity.
Public function Const ConstSharedFragmentType &  
Public function Const ConstSharedFragmentType *  
Public function Const FConstStructView

GetConstSharedFragmentDataStruct ( FMassEntityHandle Entity,
const UScriptStruct* ConstSharedFragmentType
)

  
Public function Const FragmentType &  
Public function Const FragmentType *  
Public function Const FStructView

GetFragmentDataStruct ( FMassEntityHandle Entity,
const UScriptStruct* FragmentType
)

  
Protected function Const void

GetMatchingArchetypes ( const FMassFragmentRequirements& Requirements,
TArray< FMassArchetypeHandle >& OutValidArchetypes,
const uint32 FromArchetypeDataVersion
)

  
Public function FMassObserverManager &  
Public function FOnNewArchetypeDelegate &  
Public function const FConstSharedStruct &

GetOrCreateConstSharedFragment ( const T& Fragment
)

 Returns or creates a shared struct associated to a given shared fragment set of values identified internally by a CRC.
Public function const FConstSharedStruct &

GetOrCreateConstSharedFragment ( const UScriptStruct& InScriptStruct,
const uint8* InStructMemory
)

 Returns or creates a shared struct associated to a given shared fragment set of values identified internally by a CRC.
Public function const FConstSharedStruct &

GetOrCreateConstSharedFragment ( const FConstStructView HashingHelperStruct,
TArgs&&... InArgs
)

 Returns or creates a shared struct associated to a given shared fragment set of values identified internally by a CRC.
Public function const FConstSharedStruct &

GetOrCreateConstSharedFragment ( TArgs&&... InArgs
)

 Returns or creates a shared struct associated to a given shared fragment set of values identified internally by a CRC.
Public function const FConstSharedStruct &

GetOrCreateConstSharedFragmentByHash ( const uint32 Hash,
const T& Fragment
)

  
Public function const FSharedStruct &

GetOrCreateSharedFragment ( const UScriptStruct& InScriptStruct,
const uint8* InStructMemory
)

 Returns or creates a shared struct associated to a given shared fragment set of values identified internally by a CRC.
Public function const FSharedStruct &

GetOrCreateSharedFragment ( const T& Fragment
)

 Returns or creates a shared struct associated to a given shared fragment set of values identified internally by a CRC.
Public function const FSharedStruct &

GetOrCreateSharedFragment ( TArgs&&... InArgs
)

 Returns or creates a shared struct associated to a given shared fragment set of values identified internally by a CRC.
Public function const FSharedStruct &

GetOrCreateSharedFragment ( const FConstStructView HashingHelperStruct,
TArgs&&... InArgs
)

 Returns or creates a shared struct associated to a given shared fragment set of values identified internally by a CRC.
Public function const FSharedStruct &

GetOrCreateSharedFragmentByHash ( const uint32 Hash,
TArgs&&... InArgs
)

  
Public function FMassArchetypeHandle

GetOrCreateSuitableArchetype ( const FMassArchetypeHandle& ArchetypeHandle,
const FMassSharedFragmentBitSet& SharedFragmentBitSet,
const FMassConstSharedFragmentBitSet& ConstSharedFragmentBitSet,
const FMassArchetypeCreationParams& CreationParams
)

 A helper function to be used when creating entities with shared fragments provided, or when adding shared fragments to existing entities
Public function TSharedRef< FEntityCreationContext > The main use-case for this function is to create a blank FEntityCreationContext and hold on to it while creating a bunch of entities (with multiple calls to BatchCreate* and/or BatchBuild*) and modifying them (with mutating batched API) while not causing multiple Observers to trigger.
Public function Const UObject *  
Public function Virtual Const FString  
Public function void

GetResourceSizeEx ( FResourceSizeEx& CumulativeResourceSize
)

  
Public function Const SharedFragmentType &  
Public function Const SharedFragmentType *  
Public function Const FConstStructView

GetSharedFragmentDataStruct ( FMassEntityHandle Entity,
const UScriptStruct* SharedFragmentType
)

  
Public function TConstArrayView< FSharedStruct >  
Public function Const UWorld * Fetches the world associated with the Owner.
Public function void

Initialize ( const FMassEntityManagerStorageInitParams& InitializationParams
)

  
Public function void Default to use single threaded implementation.
Protected function Const void

InternalAppendFragmentsAndTagsToArchetypeCompositionDescriptor ( FMassArchetypeCompositionDescriptor& InOutComposition,
TConstArrayView< const UScriptStruct* > FragmentsAndTagsList
)

  
Protected function FMassArchetypeHandle

InternalCreateSimilarArchetype ( const TSharedPtr< FMassArchetypeData >& SourceArchetype,
const FMassTagBitSet& OverrideTags
)

 A "similar" archetype is an archetype exactly the same as SourceArchetype except for one composition aspect like Fragments or "Tags"
Protected function FMassArchetypeHandle

InternalCreateSimilarArchetype ( const FMassArchetypeData& SourceArchetypeRef,
FMassArchetypeCompositionDescriptor&& NewComposition
)

  
Protected function FMassArchetypeHandle

InternalCreateSimilarArchetype ( const TSharedPtr< FMassArchetypeData >& SourceArchetype,
const FMassFragmentBitSet& OverrideFragments
)

  
Public function Const bool Return true if it is an valid built entity.
Public function Const bool Returns true if Entity is has been fully built (expecting a valid Entity)
Public function Const bool Returns true if Entity is valid.
Public function Const bool Indicates whether there are processors out there performing operations on this instance of MassEntityManager.
Public function void Moves an entity over to a new archetype by copying over fragments common to both archetypes
Public function FScopedProcessing  
Protected function void

OnPostFork ( EForkProcessRole Role
)

 Called on the child process upon process's forking
Public function void  
Public function void Releases a previously reserved entity that was not yet built, otherwise call DestroyEntity
Public function void  
Public function bool

RemoveConstSharedFragmentFromEntity ( const FMassEntityHandle Entity,
const UScriptStruct& ConstSharedFragmentType
)

 Removes a const shared fragment of the given type from the entity.
Public function void

RemoveFragmentFromEntity ( FMassEntityHandle Entity,
const UScriptStruct* FragmentType
)

  
Public function void

RemoveFragmentListFromEntity ( FMassEntityHandle Entity,
TConstArrayView< const UScriptStruct* > FragmentList
)

  
Public function void

RemoveTagFromEntity ( FMassEntityHandle Entity,
const UScriptStruct* TagType
)

  
Public function FMassEntityHandle Reserves an entity in the subsystem, the entity is still not ready to be used by the subsystem, need to call BuildEntity()
Public function void

SetDebugName ( const FString& NewDebugGame
)

  
Public function void

SetEntityFragmentsValues ( FMassEntityHandle Entity,
TArrayView< const FInstancedStruct > FragmentInstanceList
)

 Copies values from FragmentInstanceList over to Entity's fragment.
Public function void

SwapTagsForEntity ( FMassEntityHandle Entity,
const UScriptStruct* FromFragmentType,
const UScriptStruct* ToFragmentType
)

  

Classes

  Type Name Description
Public struct FEntityCreationContext A dedicated structure for ensuring the "on entities creation" observers get notified only once all other initialization operations are done and this creation context instance gets released.  
Public struct FScopedProcessing    

Typedefs

Name Description
FEntityStorageContainerType  
FOnNewArchetypeDelegate  
FStructInitializationCallback  

Constants

Name Description
InvalidEntity  
NumReservedEntities Index 0 is reserved so we can treat that index as an invalid entity handle.

See Also

FMassCommandBuffer for more details.

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