GLM Version 0.9.0
Functions

glm::core::function::integer Namespace Reference

Define integer functions from Section 8.8 of GLSL 4.00.8 specification. More...

Functions

template<typename T , template< typename > class C>
C< T >::signed_type bitCount (C< T > const &Value)
 Returns the number of bits set to 1 in the binary representation of value.
template<typename genIUType >
genIUType bitfieldExtract (genIUType const &Value, int const &Offset, int const &Bits)
 Extracts bits [offset, offset + bits - 1] from value, returning them in the least significant bits of the result.
template<typename genIUType >
genIUType bitfieldInsert (genIUType const &Base, genIUType const &Insert, int const &Offset, int const &Bits)
 Returns the insertion the bits least-significant bits of insert into base.
template<typename genIUType >
genIUType bitfieldReverse (genIUType const &value)
 Returns the reversal of the bits of value.
template<typename T , template< typename > class C>
C< T >::signed_type findLSB (C< T > const &Value)
 Returns the bit number of the least significant bit set to 1 in the binary representation of value.
template<typename T , template< typename > class C>
C< T >::signed_type findMSB (C< T > const &Value)
 Returns the bit number of the most significant bit in the binary representation of value.
template<typename genIType >
void imulExtended (genIType const &x, genIType const &y, genIType &msb, genIType &lsb)
 Multiplies 32-bit integers x and y, producing a 64-bit result.
template<typename genUType >
genUType uaddCarry (genUType const &x, genUType const &y, genUType &carry)
 Adds 32-bit unsigned integer x and y, returning the sum modulo pow(2, 32).
template<typename genUType >
void umulExtended (genUType const &x, genUType const &y, genUType &msb, genUType &lsb)
 Multiplies 32-bit integers x and y, producing a 64-bit result.
template<typename genUType >
genUType usubBorrow (genUType const &x, genUType const &y, genUType &borrow)
 Subtracts the 32-bit unsigned integer y from x, returning the difference if non-negative, or pow(2, 32) plus the difference otherwise.

Detailed Description

Define integer functions from Section 8.8 of GLSL 4.00.8 specification.


Function Documentation

C<T>::signed_type glm::core::function::integer::bitCount ( C< T > const &  Value)

Returns the number of bits set to 1 in the binary representation of value.

(From GLSL 4.00.08 specification, section 8.8)

genIUType glm::core::function::integer::bitfieldExtract ( genIUType const &  Value,
int const &  Offset,
int const &  Bits 
)

Extracts bits [offset, offset + bits - 1] from value, returning them in the least significant bits of the result.

For unsigned data types, the most significant bits of the result will be set to zero. For signed data types, the most significant bits will be set to the value of bit offset + base – 1.

If bits is zero, the result will be zero. The result will be undefined if offset or bits is negative, or if the sum of offset and bits is greater than the number of bits used to store the operand.

(From GLSL 4.00.08 specification, section 8.8)

genIUType glm::core::function::integer::bitfieldInsert ( genIUType const &  Base,
genIUType const &  Insert,
int const &  Offset,
int const &  Bits 
)

Returns the insertion the bits least-significant bits of insert into base.

The result will have bits [offset, offset + bits - 1] taken from bits [0, bits – 1] of insert, and all other bits taken directly from the corresponding bits of base. If bits is zero, the result will simply be base. The result will be undefined if offset or bits is negative, or if the sum of offset and bits is greater than the number of bits used to store the operand.

(From GLSL 4.00.08 specification, section 8.8)

genIUType glm::core::function::integer::bitfieldReverse ( genIUType const &  value)

Returns the reversal of the bits of value.

The bit numbered n of the result will be taken from bit (bits - 1) - n of value, where bits is the total number of bits used to represent value. (From GLSL 4.00.08 specification, section 8.8)

C<T>::signed_type glm::core::function::integer::findLSB ( C< T > const &  Value)

Returns the bit number of the least significant bit set to 1 in the binary representation of value.

If value is zero, -1 will be returned. (From GLSL 4.00.08 specification, section 8.8)

C<T>::signed_type glm::core::function::integer::findMSB ( C< T > const &  Value)

Returns the bit number of the most significant bit in the binary representation of value.

For positive integers, the result will be the bit number of the most significant bit set to 1. For negative integers, the result will be the bit number of the most significant bit set to 0. For a value of zero or negative one, -1 will be returned. (From GLSL 4.00.08 specification, section 8.8)

void glm::core::function::integer::imulExtended ( genIType const &  x,
genIType const &  y,
genIType &  msb,
genIType &  lsb 
)

Multiplies 32-bit integers x and y, producing a 64-bit result.

The 32 least-significant bits are returned in lsb. The 32 most-significant bits are returned in msb. (From GLSL 4.00.08 specification, section 8.8)

genUType glm::core::function::integer::uaddCarry ( genUType const &  x,
genUType const &  y,
genUType &  carry 
)

Adds 32-bit unsigned integer x and y, returning the sum modulo pow(2, 32).

The value carry is set to 0 if the sum was less than pow(2, 32), or to 1 otherwise.

(From GLSL 4.00.08 specification, section 8.8)

void glm::core::function::integer::umulExtended ( genUType const &  x,
genUType const &  y,
genUType &  msb,
genUType &  lsb 
)

Multiplies 32-bit integers x and y, producing a 64-bit result.

The 32 least-significant bits are returned in lsb. The 32 most-significant bits are returned in msb. (From GLSL 4.00.08 specification, section 8.8)

genUType glm::core::function::integer::usubBorrow ( genUType const &  x,
genUType const &  y,
genUType &  borrow 
)

Subtracts the 32-bit unsigned integer y from x, returning the difference if non-negative, or pow(2, 32) plus the difference otherwise.

The value borrow is set to 0 if x >= y, or to 1 otherwise.

(From GLSL 4.00.08 specification, section 8.8)