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TSparseArray

Forward declarations.

API > API/Runtime > API/Runtime/Core

A dynamically sized array where element indices aren't necessarily contiguous. Memory is allocated for all elements in the array's index range, so it doesn't save memory; but it does allow O(1) element removal that doesn't invalidate the indices of subsequent elements. It uses TArray to store the elements, and a TBitArray to store whether each element index is allocated (for fast iteration over allocated elements).

   
Name TSparseArray
Type class
Header File /Engine/Source/Runtime/Core/Public/Containers/SparseArray.h
Include Path #include "Containers/SparseArray.h"

Syntax

template<typename InElementType, typename Allocator>  
class TSparseArray : public TSparseArrayBase< sizeof, alignof, Allocator >

Inheritance Hierarchy

Constructors

Name Remarks Include Path Unreal Specifiers

TSparseArray ( TSparseArray&& InCopy
)

 Move constructor. Containers/SparseArray.h  

consteval TSparseArray ( EConstEval
)

   Containers/SparseArray.h  

TSparseArray ( std::initializer_list< ElementType > InList
)

 Initializer list constructor. Containers/SparseArray.h  

constexpr TSparseArray ()

 Default constructor. Containers/SparseArray.h  

TSparseArray ( const TSparseArray& InCopy
)

 Copy constructor. Containers/SparseArray.h  
  Containers/SparseArray.h  

Destructors

Name Remarks Include Path Unreal Specifiers

~TSparseArray()

 Destructor. Containers/SparseArray.h  

Classes

Name Remarks
FElementCompareClass Extracts the element value from the array's element structure and passes it to the user provided comparison class.
TBaseIterator The base class of sparse array iterators.
TConstIterator Iterates over all allocated elements in a const sparse array.
TConstSubsetIterator An iterator which only iterates over the elements of the array which correspond to set bits in a separate bit array.
TIterator Iterates over all allocated elements in a sparse array.
TRangedForConstIterator  
TRangedForIterator  

Typedefs

Name Type Remarks Include Path
ElementType InElementType   Containers/SparseArray.h
FElementOrFreeListLink typename SuperType::FElementOrFreeListLink   Containers/SparseArray.h
IntrusiveUnsetOptionalStateType TSparseArray   Containers/SparseArray.h
SuperType TSparseArrayBase< sizeof(InElementType), alignof(InElementType), Allocator >   Containers/SparseArray.h

Constants

Name Type Remarks Include Path
bHasIntrusiveUnsetOptionalState bool Start - intrusive TOptional state //. Containers/SparseArray.h

Functions

Public

Name Remarks Include Path Unreal Specifiers

int32 Add ( const ElementType& Element
)

 Adds an element to the array. Containers/SparseArray.h  

int32 Add ( ElementType&& Element
)

 Adds an element to the array. Containers/SparseArray.h  
  Containers/SparseArray.h  
DO NOT USE DIRECTLY STL-like iterators to enable range-based for loop support. Containers/SparseArray.h  

void CheckAddress ( const ElementType* Addr
) const

 Checks that the specified address is not part of an element within the container. Containers/SparseArray.h  

bool CompactStable ()

 Compacts the allocated elements into a contiguous index range. Containers/SparseArray.h  

void CopyUnfrozen ( const FMemoryUnfreezeContent& Context,
void* Dst
) const

   Containers/SparseArray.h  

void CountBytes ( FArchive& Ar
) const

 Tracks the container's memory use through an archive. Containers/SparseArray.h  

TConstIterator CreateConstIterator()

 Creates a const iterator for the contents of this array Containers/SparseArray.h  

TIterator CreateIterator()

 Creates an iterator for the contents of this array Containers/SparseArray.h  

int32 Emplace ( ArgsType&&... Args
)

 Constructs a new item at the last freed index of the array. Containers/SparseArray.h  

int32 EmplaceAt ( int32 Index,
ArgsType&&... Args
)

 Constructs a new item at a given index of the array. Containers/SparseArray.h  

int32 EmplaceAtLowestFreeIndex ( int32& LowestFreeIndexSearchStart,
ArgsType&&... Args
)

 Constructs a new item at the lowest free index of the array. Containers/SparseArray.h  

void Empty ( int32 ExpectedNumElements
)

 Removes all elements from the array, potentially leaving space allocated for an expected number of elements about to be added. Containers/SparseArray.h  
  Containers/SparseArray.h  
  Containers/SparseArray.h  
Finds the index of an arbitrary element. Containers/SparseArray.h  

SIZE_T GetAllocatedSize()

 Helper function to return the amount of memory allocated by this container Only returns the size of allocations made directly by the container, not the elements themselves. Containers/SparseArray.h  

int32 IndexOfByPredicate ( Predicate Pred
) const

 Finds an item by predicate. Containers/SparseArray.h  

void Insert ( int32 Index,
typename TTypeTraits< ElementType >::ConstInitType Element
)

 Inserts an element to the array. Containers/SparseArray.h  

bool IsCompact()

   Containers/SparseArray.h  

int32 PointerToIndex ( const ElementType* Ptr
) const

   Containers/SparseArray.h  

void RemoveAt ( int32 Index,
int32 Count
)

 Removes Count elements from the array, starting from Index. Containers/SparseArray.h  

void Reset()

 Empties the array, but keep its allocated memory as slack. Containers/SparseArray.h  

void Sort ()

 Sorts the elements assuming < operator is defined for ElementType. Containers/SparseArray.h  

void Sort ( const PREDICATE_CLASS& Predicate
)

 Sorts the elements using the provided comparison class. Containers/SparseArray.h  

void StableSort ()

 Stable sorts the elements assuming < operator is defined for ElementType. Containers/SparseArray.h  

void StableSort ( const PREDICATE_CLASS& Predicate
)

 Stable sorts the elements using the provided comparison class. Containers/SparseArray.h  

void WriteMemoryImage ( FMemoryImageWriter& Writer
) const

   Containers/SparseArray.h  

Static

Name Remarks Include Path Unreal Specifiers

static void AppendHash ( const FPlatformTypeLayoutParameters& LayoutParams,
FSHA1& Hasher
)

   Containers/SparseArray.h  

static void Move ( SparseArrayType& ToArray,
SparseArrayType& FromArray
)

   Containers/SparseArray.h  

Operators

Name Remarks Include Path Unreal Specifiers

bool operator!= ( const TSparseArray& B
) const

 Inequality comparison operator. Containers/SparseArray.h  

ElementType & operator[] ( int32 Index
)

 Accessors. Containers/SparseArray.h  

const ElementType & operator[] ( int32 Index
) const

   Containers/SparseArray.h  

TSparseArray & operator+= ( const TSparseArray& OtherArray
)

 Concatenation operators Containers/SparseArray.h  

TSparseArray & operator+= ( const TArray< ElementType >& OtherArray
)

   Containers/SparseArray.h  
Move assignment operator. Containers/SparseArray.h  

TSparseArray & operator= ( const TSparseArray& InCopy
)

 Copy assignment operator. Containers/SparseArray.h  

TSparseArray & operator= ( std::initializer_list< ElementType > InList
)

 Initializer list assignment operator. Containers/SparseArray.h  

bool operator== ( const TSparseArray& B
) const

 Equality comparison operator. Containers/SparseArray.h  
  Containers/SparseArray.h  

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