amrex::Morton Namespace Reference

Functions
__host__ __device__ std::uint32_t	makeSpace (std::uint32_t x) noexcept
	This makes space in the input 32-bit integer by splitting the bits so they can be interleaved.
__host__ __device__ std::uint32_t	toUInt10 (amrex::Real x, amrex::Real xmin, amrex::Real xmax) noexcept
	Convert a Real to a uint32, keeping only 10 significant bits. This puts the first 10 bits of x into retval with the 22 highest bits set to 0. It is assumed that xmin <= x < xmax.
__host__ __device__ std::uint32_t	toUInt16 (amrex::Real x, amrex::Real xmin, amrex::Real xmax) noexcept
	Convert a Real to a uint32, keeping only 16 significant bits. This puts the first 16 bits of x into retval with the 16 highest bits set to 0. It is assumed that xmin <= x < xmax.
__host__ __device__ std::uint32_t	toUInt32 (amrex::Real x, amrex::Real xmin, amrex::Real xmax) noexcept
	Convert a Real to a uint32, keeping all significant bits. It is assumed that xmin <= x < xmax.
__host__ __device__ std::uint32_t	get32BitCode (Real x, Real y, Real z, const GpuArray< amrex::Real, 3 > &plo, const GpuArray< amrex::Real, 3 > &phi) noexcept
	Given a 3D real-space coordinate, returns a Morton code stored in an unsigned 32 bit integer.
__host__ __device__ std::uint32_t	get32BitCode (const XDim3 &p, const GpuArray< amrex::Real, 3 > &plo, const GpuArray< amrex::Real, 3 > &phi) noexcept
	Given a 3D real-space coordinate, returns a Morton code stored in an unsigned 32 bit integer.

Function Documentation

get32BitCode() [1/2]

__host__ __device__ std::uint32_t amrex::Morton::get32BitCode ( const XDim3 &  p, const GpuArray< amrex::Real, 3 > &  plo, const GpuArray< amrex::Real, 3 > &  phi  )

inlinenoexcept

Given a 3D real-space coordinate, returns a Morton code stored in an unsigned 32 bit integer.

Same as the above, except takes an XDim3. Assumes 3D.

Parameters

p	the coordinate to convert.
plo	the low end of the domain.
phi	the high end of the domain.

get32BitCode() [2/2]

__host__ __device__ std::uint32_t amrex::Morton::get32BitCode ( Real  x, Real  y, Real  z, const GpuArray< amrex::Real, 3 > &  plo, const GpuArray< amrex::Real, 3 > &  phi  )

inlinenoexcept

Given a 3D real-space coordinate, returns a Morton code stored in an unsigned 32 bit integer.

In 3D, this works by converting the coordinate to a 10-bit nonnegative integer in each direction and then interleaving the bits.

In 2D, it is same except the lowest 16 bits of of the coordinates are kept.

It is assumed that plo <= p < phi has already been enforced.

Parameters

x	the coordinates to convert.
y	the coordinates to convert.
z	the coordinates to convert.
plo	the low end of the domain.
phi	the high end of the domain.

makeSpace()

__host__ __device__ std::uint32_t amrex::Morton::makeSpace ( std::uint32_t  x )

inlinenoexcept

This makes space in the input 32-bit integer by splitting the bits so they can be interleaved.

In 3D, the lowest 10 bits of x are assumed filled, with the next 22 0. On output, x has been "stretched" to 30 bits, with each input bit followed by two interleaving bits set to 0.

In 2D, it is the same except the lowest 16 bits on x are filled, and there is only one interleaving bit.

In 1D no interleaving is needed and x is just returned.

Parameters

x	unsigned int holding the input to be split

toUInt10()

__host__ __device__ std::uint32_t amrex::Morton::toUInt10 ( amrex::Real  x, amrex::Real  xmin, amrex::Real  xmax  )

inlinenoexcept

Convert a Real to a uint32, keeping only 10 significant bits. This puts the first 10 bits of x into retval with the 22 highest bits set to 0. It is assumed that xmin <= x < xmax.

This is useful in 3D, because you can interleave the bits of 3 10-bit numbers and store the result in one 32-bit integer.

Parameters

x	the coordinate to convert.
xmin	the low end of the domain.
xmax	the high end of the domain.

toUInt16()

__host__ __device__ std::uint32_t amrex::Morton::toUInt16 ( amrex::Real  x, amrex::Real  xmin, amrex::Real  xmax  )

inlinenoexcept

Convert a Real to a uint32, keeping only 16 significant bits. This puts the first 16 bits of x into retval with the 16 highest bits set to 0. It is assumed that xmin <= x < xmax.

This is useful in 2D, because you can interleave the bits of two 16-bit numbers and store the result in one 32-bit integer.

Parameters

x	the coordinate to convert.
xmin	the low end of the domain.
xmax	the high end of the domain.

toUInt32()

__host__ __device__ std::uint32_t amrex::Morton::toUInt32 ( amrex::Real  x, amrex::Real  xmin, amrex::Real  xmax  )

inlinenoexcept

Convert a Real to a uint32, keeping all significant bits. It is assumed that xmin <= x < xmax.

This is useful in 1D, because no interleaving is needed.

Parameters

x	the coordinate to convert.
xmin	the low end of the domain.
xmax	the high end of the domain.