Panda3D
Public Types | Public Member Functions | Static Public Member Functions
BitMask< WType, nbits > Class Template Reference

A general bitmask class. More...

#include "bitMask.h"

List of all members.

Public Types

enum  { num_bits = nbits }
typedef WType WordType

Public Member Functions

 BitMask (WordType init_value)
 BitMask (const BitMask< WType, nbits > &copy)
void clear ()
 Sets all the bits in the BitMask off.
void clear_bit (int index)
 Sets the nth bit off.
void clear_range (int low_bit, int size)
 Sets the indicated range of bits off.
int compare_to (const BitMask< WType, nbits > &other) const
 Returns a number less than zero if this BitMask sorts before the indicated other BitMask, greater than zero if it sorts after, or 0 if they are equivalent.
WordType extract (int low_bit, int size) const
 Returns a word that represents only the indicated range of bits within this BitMask, shifted to the least-significant position.
BitMask< WType, nbits > flood_bits_down () const
 Returns a BitMask with the bits flooded down.
BitMask< WType, nbits > flood_bits_up () const
 Returns a BitMask with the bits flooded upwards.
void flood_down_in_place ()
 Floods this bitmask's bits downwards.
void flood_up_in_place ()
 Floods this bitmask's bits upwards.
void generate_hash (ChecksumHashGenerator &hashgen) const
 Adds the bitmask to the indicated hash generator.
bool get_bit (int index) const
 Returns true if the nth bit is set, false if it is cleared.
int get_highest_off_bit () const
 Returns the index of the highest 0 bit in the mask.
int get_highest_on_bit () const
 Returns the index of the highest 1 bit in the mask.
int get_key () const
 Returns a mostly unique integer key per unique bitmask, suitable for using in a hash table.
int get_lowest_off_bit () const
 Returns the index of the lowest 0 bit in the mask.
int get_lowest_on_bit () const
 Returns the index of the lowest 1 bit in the mask.
int get_next_higher_different_bit (int low_bit) const
 Returns the index of the next bit in the mask, above low_bit, whose value is different that the value of low_bit.
int get_num_off_bits () const
 Returns the number of bits that are set to 0 in the mask.
int get_num_on_bits () const
 Returns the number of bits that are set to 1 in the mask.
WordType get_word () const
 Returns the entire BitMask as a single word.
bool has_all_of (int low_bit, int size) const
 Returns true if all bits in the indicated range are set, false otherwise.
bool has_any_of (int low_bit, int size) const
 Returns true if any bit in the indicated range is set, false otherwise.
bool has_bits_in_common (const BitMask< WType, nbits > &other) const
 Returns true if this BitMask has any "one" bits in common with the other one, false otherwise.
void invert_in_place ()
 Inverts all the bits in the BitMask.
bool is_all_on () const
 Returns true if the entire bitmask is one, false otherwise.
bool is_zero () const
 Returns true if the entire bitmask is zero, false otherwise.
BitMask< WType, nbits > keep_next_highest_bit () const
 Returns a BitMask with only the next highest bit above the indicated bit on, or all_off.
BitMask< WType, nbits > keep_next_highest_bit (int index) const
 Returns a BitMask with only the next highest bit above the indicated bit on, or all.
BitMask< WType, nbits > keep_next_highest_bit (const BitMask< WType, nbits > &other) const
 Returns a BitMask with only the next highest "on" bit above all "on" bits in the passed in bitmask, or all_off.
BitMask< WType, nbits > keep_next_lowest_bit () const
 Returns a BitMask with only the next lower bit below the indicated bit on, or all_off.
BitMask< WType, nbits > keep_next_lowest_bit (int index) const
 Returns a BitMask with only the next lower bit below the indicated bit on, or all_off.
BitMask< WType, nbits > keep_next_lowest_bit (const BitMask< WType, nbits > &other) const
 Returns a BitMask with only the next lowest "on" bit below all "on" bits in the passed in bitmask, or all_off.
bool operator!= (const BitMask< WType, nbits > &other) const
BitMask< WType, nbits > operator& (const BitMask< WType, nbits > &other) const
void operator&= (const BitMask< WType, nbits > &other)
bool operator< (const BitMask< WType, nbits > &other) const
 The ordering operator is of limited usefulness with a BitMask, however, it has a definition which places all unique BitMasks into a unique ordering.
BitMask< WType, nbits > operator<< (int shift) const
void operator<<= (int shift)
BitMask< WType, nbits > & operator= (const BitMask< WType, nbits > &copy)
bool operator== (const BitMask< WType, nbits > &other) const
BitMask< WType, nbits > operator>> (int shift) const
void operator>>= (int shift)
BitMask< WType, nbits > operator^ (const BitMask< WType, nbits > &other) const
void operator^= (const BitMask< WType, nbits > &other)
BitMask< WType, nbits > operator| (const BitMask< WType, nbits > &other) const
void operator|= (const BitMask< WType, nbits > &other)
BitMask< WType, nbits > operator~ () const
void output (ostream &out) const
 Writes the BitMask out as a binary or a hex number, according to the number of bits.
void output_binary (ostream &out, int spaces_every=4) const
 Writes the BitMask out as a binary number, with spaces every four bits.
void output_hex (ostream &out, int spaces_every=4) const
 Writes the BitMask out as a hexadecimal number, with spaces every four digits.
void set_bit (int index)
 Sets the nth bit on.
void set_bit_to (int index, bool value)
 Sets the nth bit either on or off, according to the indicated bool value.
void set_range (int low_bit, int size)
 Sets the indicated range of bits on.
void set_range_to (bool value, int low_bit, int size)
 Sets the indicated range of bits to either on or off.
void set_word (WordType value)
 Sets the entire BitMask to the value indicated by the given word.
void store (WordType value, int low_bit, int size)
 Stores the indicated word into the indicated range of bits with this BitMask.
void write (ostream &out, int indent_level=0) const
 Writes the BitMask out as a binary or a hex number, according to the number of bits.

Static Public Member Functions

static BitMask< WType, nbits > all_off ()
 Returns a BitMask whose bits are all off.
static BitMask< WType, nbits > all_on ()
 Returns a BitMask whose bits are all on.
static BitMask< WType, nbits > bit (int index)
 Returns a BitMask with only the indicated bit on.
static TypeHandle get_class_type ()
static int get_max_num_bits ()
 If get_max_num_bits() returned true, this method may be called to return the maximum number of bits that may be stored in this structure.
static int get_num_bits ()
 Returns the number of bits available to set in the bitmask.
static bool has_max_num_bits ()
 Returns true if there is a maximum number of bits that may be stored in this structure, false otherwise.
static void init_type ()
static BitMask< WType, nbits > lower_on (int on_bits)
 Returns a BitMask whose lower on_bits bits are on.
static BitMask< WType, nbits > range (int low_bit, int size)
 Returns a BitMask whose size bits, beginning at low_bit, are on.

Detailed Description

template<class WType, int nbits>
class BitMask< WType, nbits >

A general bitmask class.

This stores an array of bits of some length that must fit within a given word of the indicated type. See also BitArray.

Definition at line 35 of file bitMask.h.


Member Function Documentation

template<class WType , int nbits>
BitMask< WType, nbits > BitMask< WType, nbits >::all_off ( ) [inline, static]
template<class WType , int nbits>
BitMask< WType, nbits > BitMask< WType, nbits >::all_on ( ) [inline, static]
template<class WType , int nbits>
BitMask< WType, nbits > BitMask< WType, nbits >::bit ( int  index) [inline, static]

Returns a BitMask with only the indicated bit on.

Definition at line 117 of file bitMask.I.

References BitMask< WType, nbits >::set_bit().

Referenced by BitMask< WType, nbits >::keep_next_highest_bit(), and BitMask< WType, nbits >::keep_next_lowest_bit().

template<class WType , int nbits>
void BitMask< WType, nbits >::clear ( ) [inline]
template<class WType , int nbits>
void BitMask< WType, nbits >::clear_bit ( int  index) [inline]
template<class WType , int nbits>
void BitMask< WType, nbits >::clear_range ( int  low_bit,
int  size 
) [inline]

Sets the indicated range of bits off.

Definition at line 356 of file bitMask.I.

References BitMask< WType, nbits >::range().

template<class WType, int nbits>
int BitMask< WType, nbits >::compare_to ( const BitMask< WType, nbits > &  other) const [inline]

Returns a number less than zero if this BitMask sorts before the indicated other BitMask, 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 683 of file bitMask.I.

template<class WType , int nbits>
BitMask< WType, nbits >::WordType BitMask< WType, nbits >::extract ( int  low_bit,
int  size 
) const [inline]

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

Definition at line 293 of file bitMask.I.

References BitMask< WType, nbits >::lower_on().

template<class WType , int nbits>
BitMask< WType, nbits > BitMask< WType, nbits >::flood_bits_down ( ) const [inline]

Returns a BitMask with the bits flooded down.

Definition at line 901 of file bitMask.I.

template<class WType , int nbits>
BitMask< WType, nbits > BitMask< WType, nbits >::flood_bits_up ( ) const [inline]

Returns a BitMask with the bits flooded upwards.

Definition at line 889 of file bitMask.I.

template<class WType , int nbits>
void BitMask< WType, nbits >::flood_down_in_place ( ) [inline]

Floods this bitmask's bits downwards.

Definition at line 878 of file bitMask.I.

Referenced by BitMask< WType, nbits >::keep_next_highest_bit(), and BitMask< WType, nbits >::keep_next_lowest_bit().

template<class WType , int nbits>
void BitMask< WType, nbits >::flood_up_in_place ( ) [inline]

Floods this bitmask's bits upwards.

Definition at line 867 of file bitMask.I.

Referenced by BitMask< WType, nbits >::keep_next_highest_bit(), and BitMask< WType, nbits >::keep_next_lowest_bit().

template<class WType , int nbits>
void BitMask< WType, nbits >::generate_hash ( ChecksumHashGenerator hashgen) const [inline]

Adds the bitmask to the indicated hash generator.

Definition at line 843 of file bitMask.I.

References ChecksumHashGenerator::add_int().

template<class WType , int nbits>
bool BitMask< WType, nbits >::get_bit ( int  index) const [inline]
template<class WType , int nbits>
int BitMask< WType, nbits >::get_highest_off_bit ( ) const [inline]

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

Returns -1 if there are no 0 bits.

Definition at line 467 of file bitMask.I.

template<class WType , int nbits>
int BitMask< WType, nbits >::get_highest_on_bit ( ) const [inline]

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

Returns -1 if there are no 1 bits.

Definition at line 455 of file bitMask.I.

Referenced by BitMask< WType, nbits >::keep_next_highest_bit().

template<class WType , int nbits>
int BitMask< WType, nbits >::get_key ( ) const [inline]

Returns a mostly unique integer key per unique bitmask, suitable for using in a hash table.

Definition at line 832 of file bitMask.I.

template<class WType , int nbits>
int BitMask< WType, nbits >::get_lowest_off_bit ( ) const [inline]

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

Returns -1 if there are no 0 bits.

Definition at line 443 of file bitMask.I.

template<class WType , int nbits>
int BitMask< WType, nbits >::get_lowest_on_bit ( ) const [inline]

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

Returns -1 if there are no 1 bits.

Definition at line 431 of file bitMask.I.

Referenced by RenderState::compare_to(), RenderState::cull_callback(), BitMask< WType, nbits >::keep_next_lowest_bit(), and RenderState::write_datagram().

template<class WType , int nbits>
int BitMask< WType, nbits >::get_max_num_bits ( ) [inline, static]

If get_max_num_bits() returned true, this method may be called to return the maximum number of bits that may be stored in this structure.

It is an error to call this if get_max_num_bits() return false.

It is never an error to call this method. This returns the same thing as get_num_bits(). This method is defined so generic programming algorithms can use BitMask or BitArray interchangeably.

Definition at line 187 of file bitMask.I.

template<class WType , int nbits>
int BitMask< WType, nbits >::get_next_higher_different_bit ( int  low_bit) const [inline]

Returns the index of the next bit in the mask, 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 mask.

Definition at line 484 of file bitMask.I.

template<class WType , int nbits>
int BitMask< WType, nbits >::get_num_bits ( ) [inline, static]

Returns the number of bits available to set in the bitmask.

Definition at line 199 of file bitMask.I.

template<class WType , int nbits>
int BitMask< WType, nbits >::get_num_off_bits ( ) const [inline]

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

Definition at line 419 of file bitMask.I.

template<class WType , int nbits>
int BitMask< WType, nbits >::get_num_on_bits ( ) const [inline]

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

Definition at line 407 of file bitMask.I.

Referenced by RenderState::write_datagram().

template<class WType , int nbits>
BitMask< WType, nbits >::WordType BitMask< WType, nbits >::get_word ( ) const [inline]

Returns the entire BitMask as a single word.

Definition at line 383 of file bitMask.I.

Referenced by CollisionNode::write_datagram(), and Camera::write_datagram().

template<class WType , int nbits>
bool BitMask< WType, nbits >::has_all_of ( int  low_bit,
int  size 
) const [inline]

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

Definition at line 332 of file bitMask.I.

References BitMask< WType, nbits >::range().

template<class WType , int nbits>
bool BitMask< WType, nbits >::has_any_of ( int  low_bit,
int  size 
) const [inline]

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

Definition at line 319 of file bitMask.I.

References BitMask< WType, nbits >::range().

template<class WType, int nbits>
bool BitMask< WType, nbits >::has_bits_in_common ( const BitMask< WType, nbits > &  other) const [inline]

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

This is equivalent to (mask & other) != 0, but may be faster. (Actually, it should only be faster in the BitArray case, but this method is provided for the benefit of generic programming algorithms).

Definition at line 550 of file bitMask.I.

template<class WType , int nbits>
bool BitMask< WType, nbits >::has_max_num_bits ( ) [inline, static]

Returns true if there is a maximum number of bits that may be stored in this structure, false otherwise.

If this returns true, the number may be queried in get_max_num_bits().

This method always returns true. This method is defined so generic programming algorithms can use BitMask or BitArray interchangeably.

Definition at line 168 of file bitMask.I.

template<class WType , int nbits>
void BitMask< WType, nbits >::invert_in_place ( ) [inline]

Inverts all the bits in the BitMask.

This is equivalent to mask = ~mask.

Definition at line 533 of file bitMask.I.

Referenced by BitMask< WType, nbits >::keep_next_highest_bit(), and BitMask< WType, nbits >::keep_next_lowest_bit().

template<class WType , int nbits>
bool BitMask< WType, nbits >::is_all_on ( ) const [inline]

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

Definition at line 280 of file bitMask.I.

template<class WType , int nbits>
bool BitMask< WType, nbits >::is_zero ( ) const [inline]

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

Definition at line 268 of file bitMask.I.

Referenced by PandaNode::adjust_draw_mask(), and RenderState::is_empty().

template<class WType , int nbits>
BitMask< WType, nbits > BitMask< WType, nbits >::keep_next_highest_bit ( ) const [inline]

Returns a BitMask with only the next highest bit above the indicated bit on, or all_off.

Definition at line 915 of file bitMask.I.

References BitMask< WType, nbits >::all_off(), and BitMask< WType, nbits >::bit().

template<class WType , int nbits>
BitMask< WType, nbits > BitMask< WType, nbits >::keep_next_highest_bit ( int  index) const [inline]

Returns a BitMask with only the next highest bit above the indicated bit on, or all.

Definition at line 949 of file bitMask.I.

References BitMask< WType, nbits >::flood_down_in_place(), BitMask< WType, nbits >::flood_up_in_place(), BitMask< WType, nbits >::invert_in_place(), and BitMask< WType, nbits >::set_bit().

template<class WType, int nbits>
BitMask< WType, nbits > BitMask< WType, nbits >::keep_next_highest_bit ( const BitMask< WType, nbits > &  other) const [inline]

Returns a BitMask with only the next highest "on" bit above all "on" bits in the passed in bitmask, or all_off.

If there are no "on" bits in the passed in bitmask, it will return keep_next_highest_bit().

Definition at line 1003 of file bitMask.I.

References BitMask< WType, nbits >::get_highest_on_bit().

template<class WType , int nbits>
BitMask< WType, nbits > BitMask< WType, nbits >::keep_next_lowest_bit ( ) const [inline]

Returns a BitMask with only the next lower bit below the indicated bit on, or all_off.

Definition at line 932 of file bitMask.I.

References BitMask< WType, nbits >::all_off(), and BitMask< WType, nbits >::bit().

template<class WType , int nbits>
BitMask< WType, nbits > BitMask< WType, nbits >::keep_next_lowest_bit ( int  index) const [inline]

Returns a BitMask with only the next lower bit below the indicated bit on, or all_off.

Definition at line 975 of file bitMask.I.

References BitMask< WType, nbits >::flood_down_in_place(), BitMask< WType, nbits >::flood_up_in_place(), BitMask< WType, nbits >::invert_in_place(), and BitMask< WType, nbits >::set_bit().

template<class WType, int nbits>
BitMask< WType, nbits > BitMask< WType, nbits >::keep_next_lowest_bit ( const BitMask< WType, nbits > &  other) const [inline]

Returns a BitMask with only the next lowest "on" bit below all "on" bits in the passed in bitmask, or all_off.

If there are no "on" bits in the passed in bitmask, it will return keep_next_lowest_bit().

Definition at line 1022 of file bitMask.I.

References BitMask< WType, nbits >::get_lowest_on_bit().

template<class WType , int nbits>
BitMask< WType, nbits > BitMask< WType, nbits >::lower_on ( int  on_bits) [inline, static]

Returns a BitMask whose lower on_bits bits are on.

Definition at line 99 of file bitMask.I.

Referenced by BitMask< WType, nbits >::extract().

template<class WType, int nbits>
bool BitMask< WType, nbits >::operator< ( const BitMask< WType, nbits > &  other) const [inline]

The ordering operator is of limited usefulness with a BitMask, however, it has a definition which places all unique BitMasks into a unique ordering.

It may be useful when defining ordered STL containers of BitMasks, for instance; and it's required in order to export any STL container (ordered or unordered) of BitMask under Windows.

Definition at line 669 of file bitMask.I.

template<class WType , int nbits>
void BitMask< WType, nbits >::output ( ostream &  out) const

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

Definition at line 573 of file bitMask.I.

template<class WType , int nbits>
void BitMask< WType, nbits >::output_binary ( ostream &  out,
int  spaces_every = 4 
) const

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

Definition at line 589 of file bitMask.I.

template<class WType , int nbits>
void BitMask< WType, nbits >::output_hex ( ostream &  out,
int  spaces_every = 4 
) const

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

Definition at line 606 of file bitMask.I.

Referenced by EggGroup::write_collide_flags().

template<class WType , int nbits>
BitMask< WType, nbits > BitMask< WType, nbits >::range ( int  low_bit,
int  size 
) [inline, static]
template<class WType , int nbits>
void BitMask< WType, nbits >::set_bit ( int  index) [inline]
template<class WType , int nbits>
void BitMask< WType, nbits >::set_bit_to ( int  index,
bool  value 
) [inline]

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

index must be in the range [0, num_bits).

Definition at line 252 of file bitMask.I.

template<class WType , int nbits>
void BitMask< WType, nbits >::set_range ( int  low_bit,
int  size 
) [inline]

Sets the indicated range of bits on.

Definition at line 344 of file bitMask.I.

References BitMask< WType, nbits >::range().

template<class WType , int nbits>
void BitMask< WType, nbits >::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 368 of file bitMask.I.

template<class WType , int nbits>
void BitMask< WType, nbits >::set_word ( WordType  value) [inline]

Sets the entire BitMask to the value indicated by the given word.

Definition at line 395 of file bitMask.I.

Referenced by CollisionNode::fillin(), and Camera::fillin().

template<class WType , int nbits>
void BitMask< WType, nbits >::store ( WordType  value,
int  low_bit,
int  size 
) [inline]

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

Definition at line 306 of file bitMask.I.

References BitMask< WType, nbits >::range().

template<class WType , int nbits>
void BitMask< WType, nbits >::write ( ostream &  out,
int  indent_level = 0 
) const

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

Definition at line 630 of file bitMask.I.


The documentation for this class was generated from the following files:
 All Classes Functions Variables Enumerations