Overloading Grid::FloatGrid with Z-Curve Order for elements of the LeafNode

gistfile1.cpp

#ifdef OPENVDB_USE_ZORDER
namespace openvdb {
namespace v3_0_0 {
namespace tree {
inline uint32_t splitBy3(uint32_t x)
{
  return (x & 0x1) | ((x & 0x2) << 2) | ((x & 0x4) << 4);
}

template<>
inline openvdb::Index
LeafNode<float, 3>::coordToOffset(const openvdb::Coord& xyz)
{
  assert ((xyz[0] & (DIM-1u)) < DIM && (xyz[1] & (DIM-1u)) < DIM && (xyz[2] & (DIM-1u)) < DIM);
  return splitBy3(xyz[0]) | (splitBy3(xyz[1]) << 1) | (splitBy3(xyz[2]) << 2);
}

template<>
inline openvdb::Coord
LeafNode<float, 3>::offsetToLocalCoord(openvdb::Index n)
{
  return Coord(
    /*x=*/(n & 0x001) | (n & 0x008) | (n & 0x080),
    /*y=*/(n & 0x002) | (n & 0x010) | (n & 0x100),
    /*z=*/(n & 0x004) | (n & 0x020) | (n & 0x200)
  );
}
}
}
}
#endif