Name

bitfieldReverse - return the reversed bitfield.

Synopsis

int  bitfieldReverse(int  x)
int2 bitfieldReverse(int2 x)
int3 bitfieldReverse(int3 x)
int4 bitfieldReverse(int4 x)

uint  bitfieldReverse(uint  x)
uint2 bitfieldReverse(uint2 x)
uint3 bitfieldReverse(uint3 x)
uint4 bitfieldReverse(uint4 x)

Parameters

x

Bitfield to reverse.

Description

Returns the reverse of the bitfield x.

Reference Implementation

bitfieldReverse for an int bitfield can be implemented like this:

int bitfieldReverse(int x)
{
  int res = 0;
  int i, shift, mask;

  for(i = 0; i < 32; i++) {
    mask = 1 << i;
    shift = 32 - 2*i - 1;
    mask &= x;
    mask = (shift > 0) ? mask << shift : mask >> -shift;
    res |= mask;
  }

  return res;
}

Profile Support

bitfieldReverse is supported in gp5 and hlsl11 profiles.

See Also

  http://www.opengl.org/registry/specs/ARB/gpu_shader5.txt

bitfieldInsert, bitfieldExtract, bitCount, findLSB and findMSB