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Public Types | Public Member Functions | Static Public Member Functions | List of all members
BitArray Class Reference

A dynamic array with an unlimited number of bits. More...

#include "bitArray.h"

Public Types

enum  { num_bits_per_word = MaskType::num_bits }
 
typedef BitMaskNative MaskType
 
typedef MaskType::WordType WordType
 

Public Member Functions

 BitArray (WordType init_value)
 
 BitArray (const SparseArray &from)
 
void clear ()
 Sets all the bits in the BitArray off. More...
 
void clear_bit (int index)
 Sets the nth bit off. More...
 
void clear_range (int low_bit, int size)
 Sets the indicated range of bits off. More...
 
int compare_to (const BitArray &other) const
 Returns a number less than zero if this BitArray sorts before the indicated other BitArray, greater than zero if it sorts after, or 0 if they are equivalent. More...
 
WordType extract (int low_bit, int size) const
 Returns a word that represents only the indicated range of bits within this BitArray, shifted to the least-significant position. More...
 
void generate_hash (ChecksumHashGenerator &hashgen) const
 Adds the bitmask to the indicated hash generator. More...
 
bool get_bit (int index) const
 Returns true if the nth bit is set, false if it is cleared. More...
 
bool get_highest_bits () const
 Returns true if the infinite set of bits beyond get_num_bits() are all on, or false of they are all off. More...
 
int get_highest_off_bit () const
 Returns the index of the highest 0 bit in the array. More...
 
int get_highest_on_bit () const
 Returns the index of the highest 1 bit in the array. More...
 
int get_lowest_off_bit () const
 Returns the index of the lowest 0 bit in the array. More...
 
int get_lowest_on_bit () const
 Returns the index of the lowest 1 bit in the array. More...
 
int get_next_higher_different_bit (int low_bit) const
 Returns the index of the next bit in the array, above low_bit, whose value is different that the value of low_bit. More...
 
size_t get_num_bits () const
 Returns the current number of possibly different bits in this array. More...
 
int get_num_off_bits () const
 Returns the number of bits that are set to 0 in the array. More...
 
int get_num_on_bits () const
 Returns the number of bits that are set to 1 in the array. More...
 
size_t get_num_words () const
 Returns the number of possibly-unique words stored in the array. More...
 
MaskType get_word (size_t n) const
 Returns the nth word in the array. More...
 
bool has_all_of (int low_bit, int size) const
 Returns true if all bits in the indicated range are set, false otherwise. More...
 
bool has_any_of (int low_bit, int size) const
 Returns true if any bit in the indicated range is set, false otherwise. More...
 
bool has_bits_in_common (const BitArray &other) const
 Returns true if this BitArray has any "one" bits in common with the other one, false otherwise. More...
 
void invert_in_place ()
 Inverts all the bits in the BitArray. More...
 
bool is_all_on () const
 Returns true if the entire bitmask is one, false otherwise. More...
 
bool is_zero () const
 Returns true if the entire bitmask is zero, false otherwise. More...
 
bool operator != (const BitArray &other) const
 
BitArray operator & (const BitArray &other) const
 
void operator &= (const BitArray &other)
 
BitArray operator >> (int shift) const
 
void operator >>= (int shift)
 Logical right shift. More...
 
BitArray operator ^ (const BitArray &other) const
 
void operator ^= (const BitArray &other)
 
BitArray operator ~ () const
 
bool operator< (const BitArray &other) const
 Returns true if the unsigned integer which is represented by this BitArray is less than that of the other one, false otherwise. More...
 
BitArray operator<< (int shift) const
 
void operator<<= (int shift)
 Logical left shift. More...
 
bool operator== (const BitArray &other) const
 
BitArray operator| (const BitArray &other) const
 
void operator|= (const BitArray &other)
 
void output (std::ostream &out) const
 Writes the BitArray out as a hex number. More...
 
void output_binary (std::ostream &out, int spaces_every=4) const
 Writes the BitArray out as a binary number, with spaces every four bits. More...
 
void output_hex (std::ostream &out, int spaces_every=4) const
 Writes the BitArray out as a hexadecimal number, with spaces every four digits. More...
 
void read_datagram (DatagramIterator &scan, BamReader *manager)
 Reads the object that was previously written to a Bam file. More...
 
void set_bit (int index)
 Sets the nth bit on. More...
 
void set_bit_to (int index, bool value)
 Sets the nth bit either on or off, according to the indicated bool value. More...
 
void set_range (int low_bit, int size)
 Sets the indicated range of bits on. More...
 
void set_range_to (bool value, int low_bit, int size)
 Sets the indicated range of bits to either on or off. More...
 
void set_word (size_t n, WordType value)
 Replaces the nth word in the array. More...
 
void store (WordType value, int low_bit, int size)
 Stores the indicated word into the indicated range of bits with this BitArray. More...
 
void write (std::ostream &out, int indent_level=0) const
 Writes the BitArray out as a binary or a hex number, according to the number of bits. More...
 
void write_datagram (BamWriter *manager, Datagram &dg) const
 Writes the contents of this object to the datagram for shipping out to a Bam file. More...
 

Static Public Member Functions

static BitArray all_off ()
 Returns a BitArray whose bits are all off. More...
 
static BitArray all_on ()
 Returns a BitArray with an infinite array of bits, all on. More...
 
static BitArray bit (int index)
 Returns a BitArray with only the indicated bit on. More...
 
static TypeHandle get_class_type ()
 
static constexpr int get_max_num_bits ()
 
static constexpr int get_num_bits_per_word ()
 
static constexpr bool has_max_num_bits ()
 
static void init_type ()
 
static BitArray lower_on (int on_bits)
 Returns a BitArray whose lower on_bits bits are on. More...
 
static BitArray range (int low_bit, int size)
 Returns a BitArray whose size bits, beginning at low_bit, are on. More...
 

Detailed Description

A dynamic array with an unlimited number of bits.

This is similar to a BitMask, except it appears to contain an infinite number of bits. You can use it very much as you would use a BitMask.

Definition at line 39 of file bitArray.h.

Member Function Documentation

◆ all_off()

BitArray BitArray::all_off ( )
inlinestatic

Returns a BitArray whose bits are all off.

Definition at line 47 of file bitArray.I.

◆ all_on()

BitArray BitArray::all_on ( )
inlinestatic

Returns a BitArray with an infinite array of bits, all on.

Definition at line 37 of file bitArray.I.

◆ bit()

BitArray BitArray::bit ( int  index)
inlinestatic

Returns a BitArray with only the indicated bit on.

Definition at line 65 of file bitArray.I.

References set_bit().

◆ clear()

void BitArray::clear ( )
inline

Sets all the bits in the BitArray off.

Definition at line 272 of file bitArray.I.

◆ clear_bit()

void BitArray::clear_bit ( int  index)
inline

Sets the nth bit off.

If n >= get_num_bits(), this automatically extends the array.

Definition at line 133 of file bitArray.I.

Referenced by set_bit_to().

◆ clear_range()

void BitArray::clear_range ( int  low_bit,
int  size 
)

Sets the indicated range of bits off.

Definition at line 245 of file bitArray.cxx.

References get_num_words().

Referenced by set_range_to().

◆ compare_to()

int BitArray::compare_to ( const BitArray other) const

Returns a number less than zero if this BitArray sorts before the indicated other BitArray, greater than zero if it sorts after, or 0 if they are equivalent.

This is based on the same ordering defined by operator <.

Definition at line 582 of file bitArray.cxx.

References get_num_words().

Referenced by operator<().

◆ extract()

BitArray::WordType BitArray::extract ( int  low_bit,
int  size 
) const
inline

Returns a word that represents only the indicated range of bits within this BitArray, shifted to the least-significant position.

size must be <= get_num_bits_per_word().

Definition at line 173 of file bitArray.I.

◆ generate_hash()

void BitArray::generate_hash ( ChecksumHashGenerator hashgen) const

Adds the bitmask to the indicated hash generator.

Definition at line 855 of file bitArray.cxx.

References ChecksumHashGenerator::add_int().

◆ get_bit()

bool BitArray::get_bit ( int  index) const
inline

Returns true if the nth bit is set, false if it is cleared.

It is valid for n to increase beyond get_num_bits(), but the return value get_num_bits() will always be the same.

Definition at line 99 of file bitArray.I.

Referenced by get_next_higher_different_bit(), and MouseWatcher::is_button_down().

◆ get_highest_bits()

bool BitArray::get_highest_bits ( ) const
inline

Returns true if the infinite set of bits beyond get_num_bits() are all on, or false of they are all off.

Definition at line 163 of file bitArray.I.

◆ get_highest_off_bit()

int BitArray::get_highest_off_bit ( ) const

Returns the index of the highest 0 bit in the array.

Returns -1 if there are no 0 bits or if there an infinite number of 1 bits.

Definition at line 391 of file bitArray.cxx.

References get_num_words().

◆ get_highest_on_bit()

int BitArray::get_highest_on_bit ( ) const

Returns the index of the highest 1 bit in the array.

Returns -1 if there are no 1 bits or if there an infinite number of 1 bits.

Definition at line 372 of file bitArray.cxx.

References get_num_words().

◆ get_lowest_off_bit()

int BitArray::get_lowest_off_bit ( ) const

Returns the index of the lowest 0 bit in the array.

Returns -1 if there are no 0 bits.

Definition at line 352 of file bitArray.cxx.

References get_num_words().

◆ get_lowest_on_bit()

int BitArray::get_lowest_on_bit ( ) const

Returns the index of the lowest 1 bit in the array.

Returns -1 if there are no 1 bits.

Definition at line 332 of file bitArray.cxx.

References get_num_words().

◆ get_next_higher_different_bit()

int BitArray::get_next_higher_different_bit ( int  low_bit) const

Returns the index of the next bit in the array, above low_bit, whose value is different that the value of low_bit.

Returns low_bit again if all bits higher than low_bit have the same value.

This can be used to quickly iterate through all of the bits in the array.

Definition at line 413 of file bitArray.cxx.

References get_bit(), and get_num_words().

◆ get_num_bits()

size_t BitArray::get_num_bits ( ) const
inline

Returns the current number of possibly different bits in this array.

There are actually an infinite number of bits, but every bit higher than this bit will have the same value, either 0 or 1 (see get_highest_bits()).

This number may grow and/or shrink automatically as needed.

Definition at line 89 of file bitArray.I.

References get_num_words().

Referenced by has_all_of(), has_any_of(), output_binary(), and output_hex().

◆ get_num_off_bits()

int BitArray::get_num_off_bits ( ) const

Returns the number of bits that are set to 0 in the array.

Returns -1 if there are an infinite number of 0 bits.

Definition at line 314 of file bitArray.cxx.

◆ get_num_on_bits()

int BitArray::get_num_on_bits ( ) const

Returns the number of bits that are set to 1 in the array.

Returns -1 if there are an infinite number of 1 bits.

Definition at line 296 of file bitArray.cxx.

◆ get_num_words()

size_t BitArray::get_num_words ( ) const
inline

Returns the number of possibly-unique words stored in the array.

Definition at line 235 of file bitArray.I.

Referenced by clear_range(), compare_to(), get_highest_off_bit(), get_highest_on_bit(), get_lowest_off_bit(), get_lowest_on_bit(), get_next_higher_different_bit(), get_num_bits(), has_all_of(), has_any_of(), and set_range().

◆ get_word()

BitArray::MaskType BitArray::get_word ( size_t  n) const
inline

Returns the nth word in the array.

It is valid for n to be greater than get_num_words(), but the return value beyond get_num_words() will always be the same.

Definition at line 245 of file bitArray.I.

Referenced by has_all_of(), and has_any_of().

◆ has_all_of()

bool BitArray::has_all_of ( int  low_bit,
int  size 
) const

Returns true if all bits in the indicated range are set, false otherwise.

Definition at line 142 of file bitArray.cxx.

References get_num_bits(), get_num_words(), get_word(), and is_all_on().

◆ has_any_of()

bool BitArray::has_any_of ( int  low_bit,
int  size 
) const

Returns true if any bit in the indicated range is set, false otherwise.

Definition at line 89 of file bitArray.cxx.

References get_num_bits(), get_num_words(), get_word(), and is_zero().

◆ has_bits_in_common()

bool BitArray::has_bits_in_common ( const BitArray other) const

Returns true if this BitArray has any "one" bits in common with the other one, false otherwise.

This is equivalent to (array & other) != 0, but may be faster.

Definition at line 467 of file bitArray.cxx.

◆ invert_in_place()

void BitArray::invert_in_place ( )

Inverts all the bits in the BitArray.

This is equivalent to array = ~array.

Definition at line 451 of file bitArray.cxx.

◆ is_all_on()

bool BitArray::is_all_on ( ) const

Returns true if the entire bitmask is one, false otherwise.

Definition at line 69 of file bitArray.cxx.

Referenced by has_all_of().

◆ is_zero()

bool BitArray::is_zero ( ) const

Returns true if the entire bitmask is zero, false otherwise.

Definition at line 48 of file bitArray.cxx.

Referenced by has_any_of().

◆ lower_on()

BitArray BitArray::lower_on ( int  on_bits)
inlinestatic

Returns a BitArray whose lower on_bits bits are on.

Definition at line 55 of file bitArray.I.

References set_range().

◆ operator >>=()

void BitArray::operator >>= ( int  shift)

Logical right shift.

The rightmost bits are lost. Since this is an infinite bit array, there is no question of sign extension; there is no need to synthesize bits on the left.

Definition at line 792 of file bitArray.cxx.

References operator<<=().

Referenced by operator<<=().

◆ operator<()

bool BitArray::operator< ( const BitArray other) const
inline

Returns true if the unsigned integer which is represented by this BitArray is less than that of the other one, false otherwise.

Definition at line 298 of file bitArray.I.

References compare_to().

◆ operator<<=()

void BitArray::operator<<= ( int  shift)

Logical left shift.

The rightmost bits are filled in with zeroes. Since this is an infinite bit array, none of the bits on the left are lost.

Definition at line 727 of file bitArray.cxx.

References operator >>=().

Referenced by operator >>=().

◆ output()

void BitArray::output ( std::ostream &  out) const

Writes the BitArray out as a hex number.

For a BitArray, this is always the same as output_hex(); it's too confusing for the output format to change back and forth at runtime.

Definition at line 520 of file bitArray.cxx.

References output_hex().

◆ output_binary()

void BitArray::output_binary ( std::ostream &  out,
int  spaces_every = 4 
) const

Writes the BitArray out as a binary number, with spaces every four bits.

Definition at line 528 of file bitArray.cxx.

References get_num_bits().

◆ output_hex()

void BitArray::output_hex ( std::ostream &  out,
int  spaces_every = 4 
) const

Writes the BitArray out as a hexadecimal number, with spaces every four digits.

Definition at line 546 of file bitArray.cxx.

References get_num_bits().

Referenced by output().

◆ range()

BitArray BitArray::range ( int  low_bit,
int  size 
)
inlinestatic

Returns a BitArray whose size bits, beginning at low_bit, are on.

Definition at line 75 of file bitArray.I.

References set_range().

◆ read_datagram()

void BitArray::read_datagram ( DatagramIterator scan,
BamReader manager 
)

Reads the object that was previously written to a Bam file.

Definition at line 924 of file bitArray.cxx.

References DatagramIterator::get_uint32().

◆ set_bit()

void BitArray::set_bit ( int  index)
inline

Sets the nth bit on.

If n >= get_num_bits(), this automatically extends the array.

Definition at line 115 of file bitArray.I.

Referenced by bit(), and set_bit_to().

◆ set_bit_to()

void BitArray::set_bit_to ( int  index,
bool  value 
)
inline

Sets the nth bit either on or off, according to the indicated bool value.

Definition at line 150 of file bitArray.I.

References clear_bit(), and set_bit().

◆ set_range()

void BitArray::set_range ( int  low_bit,
int  size 
)

Sets the indicated range of bits on.

Definition at line 195 of file bitArray.cxx.

References get_num_words().

Referenced by lower_on(), range(), and set_range_to().

◆ set_range_to()

void BitArray::set_range_to ( bool  value,
int  low_bit,
int  size 
)
inline

Sets the indicated range of bits to either on or off.

Definition at line 223 of file bitArray.I.

References clear_range(), and set_range().

◆ set_word()

void BitArray::set_word ( size_t  n,
WordType  value 
)
inline

Replaces the nth word in the array.

If n >= get_num_words(), this automatically extends the array.

Definition at line 262 of file bitArray.I.

◆ store()

void BitArray::store ( WordType  value,
int  low_bit,
int  size 
)
inline

Stores the indicated word into the indicated range of bits with this BitArray.

Definition at line 197 of file bitArray.I.

◆ write()

void BitArray::write ( std::ostream &  out,
int  indent_level = 0 
) const

Writes the BitArray out as a binary or a hex number, according to the number of bits.

Definition at line 572 of file bitArray.cxx.

References indent().

◆ write_datagram()

void BitArray::write_datagram ( BamWriter manager,
Datagram dg 
) const

Writes the contents of this object to the datagram for shipping out to a Bam file.

Definition at line 911 of file bitArray.cxx.

References Datagram::add_uint32(), and Datagram::add_uint8().


The documentation for this class was generated from the following files: