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  3. TBitArray

TBitArray

A dynamically sized bit array.

API > API/Runtime > API/Runtime/Core

A dynamically sized bit array. An array of Booleans. They stored in one bit/Boolean. There are iterators that efficiently iterate over only set bits.

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

Syntax

template<typename Allocator>  
class TBitArray

Derived Classes

Constructors

Name Remarks Include Path Unreal Specifiers

TBitArray ( const TBitArray< OtherAllocator >& Copy
)

   Containers/BitArray.h  

constexpr TBitArray ()

   Containers/BitArray.h  

consteval TBitArray ( EConstEval
)

   Containers/BitArray.h  

TBitArray ( TBitArray&& Other
)

 Move constructor. Containers/BitArray.h  

TBitArray ( const TBitArray& Copy
)

 Copy constructor. Containers/BitArray.h  

TBitArray ( bool bValue,
int32 InNumBits
)

 Minimal initialization constructor. Containers/BitArray.h  

Classes

Name Remarks
FConstIterator Const BitArray iterator.
FConstReverseIterator Const reverse iterator.
FIterator BitArray iterator.
FReverseIterator Reverse iterator.

Structs

Name Remarks
FConstWordIterator  
FWordIterator  
TSupportsFreezeMemoryImageHelper  
TWordIteratorBase  

Typedefs

Name Type Remarks Include Path
AllocatorType Allocator::template ForElementType< uint32 >   Containers/BitArray.h
WordType uint32   Containers/BitArray.h

Constants

Name Type Remarks Include Path
FullWordMask WordType   Containers/BitArray.h

Variables

Protected

Name Type Remarks Include Path Unreal Specifiers
AllocatorInstance AllocatorType   Containers/BitArray.h  
MaxBits int32   Containers/BitArray.h  
NumBits int32   Containers/BitArray.h  

Functions

Public

Name Remarks Include Path Unreal Specifiers
  Containers/BitArray.h  

const FConstBitReference AccessCorrespondingBit ( const FRelativeBitReference& RelativeReference
) const

   Containers/BitArray.h  

int32 Add ( const bool Value
)

 Adds a bit to the array with the given value. Containers/BitArray.h  

int32 Add ( const bool Value,
int32 NumBitsToAdd
)

 Adds multiple bits to the array with the given value. Containers/BitArray.h  

int32 AddRange ( const InWordType* ReadBits,
int32 NumBitsToAdd,
int32 ReadOffsetBits
)

 Adds multiple bits read from the given pointer. Containers/BitArray.h  

int32 AddRange ( const TBitArray< OtherAllocator >& ReadBits,
int32 NumBitsToAdd,
int32 ReadOffsetBits
)

 Adds multiple bits read from the given BitArray. Containers/BitArray.h  

int32 AddUninitialized ( int32 NumBitsToAdd
)

 Inserts space for multiple bits at the end of the array. Containers/BitArray.h  
  Containers/BitArray.h  
Enables range-based for loops, DO NOT USE DIRECTLY. Containers/BitArray.h  

void BitwiseNOT()

 Perform a bitwise NOT on all the bits in this array Containers/BitArray.h  

void CheckInvariants()

 Checks the invariants of this class Containers/BitArray.h  

TBitArray & CombineWithBinaryOp ( const TBitArray< OtherAllocator >& InOther,
EBitwiseOperatorFlags InFlags,
BinaryOpType&& InBinaryOp
)

 Perform a custom bitwise operation on this bit array with another. Containers/BitArray.h  

TBitArray & CombineWithBitwiseAND ( const TBitArray< OtherAllocator >& InOther,
EBitwiseOperatorFlags InFlags
)

 Perform a bitwise AND on this bit array with another. Containers/BitArray.h  

TBitArray & CombineWithBitwiseOR ( const TBitArray< OtherAllocator >& InOther,
EBitwiseOperatorFlags InFlags
)

 Return the bitwise OR of two bit arrays. Containers/BitArray.h  

TBitArray & CombineWithBitwiseXOR ( const TBitArray< OtherAllocator >& InOther,
EBitwiseOperatorFlags InFlags
)

 Return the bitwise XOR of two bit arrays. Containers/BitArray.h  

bool CompareSetBits ( const TBitArray< OtherAllocator >& Other,
const bool bMissingBitValue
) const

 Returns true if Other contains all the same set bits as this, accounting for differences in length. Containers/BitArray.h  

bool Contains ( bool bValue
) const

 Checks if the array contains the specified value (true/false). Containers/BitArray.h  

void CountBytes ( FArchive& Ar
) const

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

int32 CountSetBits ( int32 FromIndex,
int32 ToIndex
) const

 Count the number of set bits in this array FromIndex <= bit < ToIndex Containers/BitArray.h  

void Empty ( int32 ExpectedNumBits
)

 Removes all bits from the array, potentially leaving space allocated for an expected number of bits about to be added. Containers/BitArray.h  
  Containers/BitArray.h  
  Containers/BitArray.h  

int32 Find ( bool bValue
) const

 Finds the first occurrence of the specified value (true/false) in the array, and returns the bit index. Containers/BitArray.h  

int32 FindAndSetFirstZeroBit ( int32 StartIndex
)

 Finds the first occurrence of a zero bit in the array and sets it to one, returning the bit index. Containers/BitArray.h  
Finds the last occurrence of a zero bit in the array and sets it to one, returning the bit index. Containers/BitArray.h  

int32 FindFrom ( bool bValue,
IndexType StartIndex,
IndexType EndIndexExclusive
) const

 Finds the first occurrence of the specified value (true/false) in the array, starting from the given bit index, and returns the bit index. Containers/BitArray.h  

int32 FindFrom ( bool bValue,
IndexType StartIndex
) const

 Finds the first occurrence of the specified value (true/false) in the array, starting from the given bit index, and returns the bit index. Containers/BitArray.h  

int32 FindLast ( bool bValue
) const

 Finds the last occurrence of the specified value (true/false) in the array, and returns the bit index. Containers/BitArray.h  

int32 FindLastFrom ( bool bValue,
IndexType EndIndexInclusive
) const

 Finds the last occurrence of the specified value (true/false) in the array starting the (reverse) search from the given bit index, and returns the bit index. Containers/BitArray.h  

uint32 GetAllocatedSize()

 Helper function to return the amount of memory allocated by this container Containers/BitArray.h  

uint32 * GetData ()

   Containers/BitArray.h  

const uint32 * GetData ()

   Containers/BitArray.h  

void GetRange ( int32 Index,
int32 NumBitsToGet,
InWordType* WriteBits,
int32 WriteOffsetBits
) const

 Reads a range of bits within the array and writes them to the given pointer. Containers/BitArray.h  

void Init ( bool bValue,
int32 InNumBits
)

 Resets the array's contents. Containers/BitArray.h  

void Insert ( bool Value,
int32 Index
)

 Adds a bit with the given value at the given index in the array. Containers/BitArray.h  

void Insert ( bool Value,
int32 Index,
int32 NumBitsToAdd
)

 Inserts multiple bits with the given value into the array, starting at the given Index. Containers/BitArray.h  

void InsertRange ( const TBitArray< OtherAllocator >& ReadBits,
int32 Index,
int32 NumBitsToAdd,
int32 ReadOffsetBits
)

 Inserts multiple bits read from the given BitArray into the array, starting at the given index. Containers/BitArray.h  

void InsertRange ( const InWordType* ReadBits,
int32 Index,
int32 NumBitsToAdd,
int32 ReadOffsetBits
)

 Inserts multiple bits read from the given pointer, starting at the given index. Containers/BitArray.h  

void InsertUninitialized ( int32 Index,
int32 NumBitsToAdd
)

 Inserts space for multiple bits into the array, starting at the given index. Containers/BitArray.h  

bool IsEmpty ()

 Returns true if the bit array is empty and contains no elements. Containers/BitArray.h  

bool IsValidIndex ( int32 InIndex
) const

 Accessors. Containers/BitArray.h  

int32 Max()

   Containers/BitArray.h  

int32 Num()

   Containers/BitArray.h  

int32 PadToNum ( int32 DesiredNum,
bool bPadValue
)

 Pad this bit array with the specified value to ensure that it is at least the specified length. Containers/BitArray.h  
  Containers/BitArray.h  
  Containers/BitArray.h  

void RemoveAt ( int32 BaseIndex,
int32 NumBitsToRemove
)

 Removes bits from the array. Containers/BitArray.h  

void RemoveAtSwap ( int32 BaseIndex,
int32 NumBitsToRemove
)

 Removes bits from the array by swapping them with bits at the end of the array. Containers/BitArray.h  
  Containers/BitArray.h  
  Containers/BitArray.h  

void Reserve ( int32 Number
)

 Reserves memory such that the array can contain at least Number bits. Containers/BitArray.h  

void Reset()

 Removes all bits from the array retaining any space already allocated. Containers/BitArray.h  

void Serialize ( FArchive& Ar
)

 Serializer Containers/BitArray.h  

void SetNum ( int32 InNumBits,
ValueType bValue
)

 Sets the number of bits, initializing any potentially added bits to the given value. Containers/BitArray.h  

void SetNumUninitialized ( int32 InNumBits
)

 Sets number of bits without initializing new bits. Containers/BitArray.h  

void SetRange ( int32 Index,
int32 NumBitsToSet,
bool Value
)

 Sets or unsets a range of bits within the array. Containers/BitArray.h  

void SetRangeFromRange ( int32 Index,
int32 NumBitsToSet,
const InWordType* ReadBits,
int32 ReadOffsetBits
)

 Sets range of bits within the TBitArray to the values read out of a pointer. Containers/BitArray.h  

void SetRangeFromRange ( int32 Index,
int32 NumBitsToSet,
const TBitArray< OtherAllocator >& ReadBits,
int32 ReadOffsetBits
)

 Sets range of bits within this TBitArray to the values read out another TBitArray. Containers/BitArray.h  

void WriteMemoryImage ( FMemoryImageWriter& Writer
) const

   Containers/BitArray.h  

Static

Name Remarks Include Path Unreal Specifiers

static TBitArray BitwiseAND ( const TBitArray< AllocatorA >& A,
const TBitArray< AllocatorB >& B,
EBitwiseOperatorFlags InFlags
)

 Return the bitwise AND of two bit arrays. Containers/BitArray.h  

static TBitArray BitwiseOR ( const TBitArray< AllocatorA >& A,
const TBitArray< AllocatorB >& B,
EBitwiseOperatorFlags InFlags
)

 Return the bitwise OR of two bit arrays. Containers/BitArray.h  

static TBitArray BitwiseXOR ( const TBitArray< AllocatorA >& A,
const TBitArray< AllocatorB >& B,
EBitwiseOperatorFlags InFlags
)

 Return the bitwise XOR of two bit arrays. Containers/BitArray.h  

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

   Containers/BitArray.h  

static void SetWords ( uint32* Words,
int32 NumWords,
bool bValue
)

   Containers/BitArray.h  

Operators

Name Remarks Include Path Unreal Specifiers

bool operator!= ( const TBitArray< Allocator >& Other
) const

   Containers/BitArray.h  

const FConstBitReference operator[] ( int32 Index
) const

   Containers/BitArray.h  

FBitReference operator[] ( int32 Index
)

   Containers/BitArray.h  

TBitArray & operator= ( const TBitArray& Copy
)

 Assignment operator. Containers/BitArray.h  

TBitArray & operator= ( TBitArray&& Other
)

 Move assignment. Containers/BitArray.h  

TBitArray & operator= ( const TBitArray< OtherAllocator >& Copy
)

   Containers/BitArray.h  

bool operator== ( const TBitArray< Allocator >& Other
) const

   Containers/BitArray.h  

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