panda3d.core.SparseArray¶

class SparseArray¶

This class records a set of integers, where each integer is either present or not present in the set.

It is similar in principle and in interface to a BitArray (which can be thought of as a set of integers, one integer corresponding to each different bit position), but the SparseArray is implemented as a list of min/max subrange lists, rather than as a bitmask.

This makes it particularly efficient for storing sets which consist of large sections of consecutively included or consecutively excluded elements, with arbitrarily large integers, but particularly inefficient for doing boolean operations such as & or |.

Also, unlike BitArray, the SparseArray can store negative integers.

Inheritance diagram

__init__() → None¶

__init__(from: BitArray) → None

__init__(param0: SparseArray) → None

static allOff() → SparseArray¶

Returns a SparseArray whose bits are all off.

Return type: SparseArray

static allOn() → SparseArray¶

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

Return type: SparseArray

static bit(index: int) → SparseArray¶

Returns a SparseArray with only the indicated bit on.

Return type: SparseArray

clear() → None¶: Sets all the bits in the SparseArray off.

clearBit(index: int) → None¶: Sets the nth bit off. If n >= getNumBits(), this automatically extends the array.

clearRange(low_bit: int, size: int) → None¶: Sets the indicated range of bits off.

compareTo(other: SparseArray) → int¶: Returns a number less than zero if this SparseArray sorts before the indicated other SparseArray, greater than zero if it sorts after, or 0 if they are equivalent. This is based on the same ordering defined by operator <.

getBit(index: int) → bool¶: Returns true if the nth bit is set, false if it is cleared. It is valid for n to increase beyond getNumBits(), but the return value getNumBits() will always be the same.

static getClassType() → TypeHandle¶

Return type: TypeHandle

getHighestBits() → bool¶: Returns true if the infinite set of bits beyond getNumBits() are all on, or false of they are all off.

getHighestOffBit() → int¶: 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.

getHighestOnBit() → int¶: 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.

getLowestOffBit() → int¶: Returns the index of the lowest 0 bit in the array. Returns -1 if there are no 0 bits or if there are an infinite number of 1 bits.

getLowestOnBit() → int¶: Returns the index of the lowest 1 bit in the array. Returns -1 if there are no 1 bits or if there are an infinite number of 1 bits.

static getMaxNumBits() → int¶

If getMaxNumBits() 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 getMaxNumBits() return false.

It is always an error to call this method. The SparseArray has no maximum number of bits. This method is defined so generic programming algorithms can use BitMask or SparseArray interchangeably.

getNextHigherDifferentBit(low_bit: int) → int¶

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.

getNumBits() → int¶

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 getHighestBits()).

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

getNumOffBits() → int¶: Returns the number of bits that are set to 0 in the array. Returns -1 if there are an infinite number of 0 bits.

getNumOnBits() → int¶: Returns the number of bits that are set to 1 in the array. Returns -1 if there are an infinite number of 1 bits.

getNumSubranges() → size_t¶

Returns the number of separate subranges stored in the SparseArray. You can use this limit to iterate through the subranges, calling getSubrangeBegin() and getSubrangeEnd() for each one.

Also see isInverse().

Return type: size_t

getSubrangeBegin(n: size_t) → int¶

Returns the first numeric element in the nth subrange.

Also see isInverse().

getSubrangeEnd(n: size_t) → int¶

Returns the last numeric element, plus one, in the nth subrange.

Also see isInverse().

hasAllOf(low_bit: int, size: int) → bool¶: Returns true if all bits in the indicated range are set, false otherwise.

hasAnyOf(low_bit: int, size: int) → bool¶: Returns true if any bit in the indicated range is set, false otherwise.

hasBitsInCommon(other: SparseArray) → bool¶

Returns true if this SparseArray has any “one” bits in common with the other one, false otherwise.

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

static hasMaxNumBits() → bool¶

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 getMaxNumBits().

This method always returns false. The SparseArray has no maximum number of bits. This method is defined so generic programming algorithms can use BitMask or SparseArray interchangeably.

invertInPlace() → None¶: Inverts all the bits in the SparseArray. This is equivalent to array = ~array.

isAllOn() → bool¶: Returns true if the entire bitmask is one, false otherwise.

isInverse() → bool¶: If this is true, the SparseArray is actually defined as a list of subranges of integers that are not in the set. If this is false (the default), then the subranges define the integers that are in the set. This affects the interpretation of the values returned by iterating through getNumSubranges().

isZero() → bool¶: Returns true if the entire bitmask is zero, false otherwise.

static lowerOn(on_bits: int) → SparseArray¶

Returns a SparseArray whose lower on_bits bits are on.

Return type: SparseArray

operator(shift: int) → SparseArray¶

Return type: SparseArray

operator(shift: int) → SparseArray¶

Return type: SparseArray

output(out: ostream) → None¶

static range(low_bit: int, size: int) → SparseArray¶

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

Return type: SparseArray

setBit(index: int) → None¶: Sets the nth bit on. If n >= getNumBits(), this automatically extends the array.

setBitTo(index: int, value: bool) → None¶: Sets the nth bit either on or off, according to the indicated bool value.

setRange(low_bit: int, size: int) → None¶: Sets the indicated range of bits on.

setRangeTo(value: bool, low_bit: int, size: int) → None¶: Sets the indicated range of bits to either on or off.