//======================================================================================================================
//
// This file is part of waLBerla. waLBerla is free software: you can
// redistribute it and/or modify it under the terms of the GNU General Public
// License as published by the Free Software Foundation, either version 3 of
// the License, or (at your option) any later version.
//
// waLBerla is distributed in the hope that it will be useful, but WITHOUT
// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
// FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
// for more details.
//
// You should have received a copy of the GNU General Public License along
// with waLBerla (see COPYING.txt). If not, see <http://www.gnu.org/licenses/>.
//
//! \\file D3Q19StorageSpecification.h
//! \\author lbmpy
//======================================================================================================================
#pragma once
#include "core/DataTypes.h"
#include "core/cell/CellInterval.h"
#include "core/mpi/SendBuffer.h"
#include "core/mpi/RecvBuffer.h"
#include "domain_decomposition/IBlock.h"
#include "field/GhostLayerField.h"
#include "stencil/D3Q19.h"
#include "stencil/Directions.h"
#define FUNC_PREFIX
#ifdef __GNUC__
#define RESTRICT __restrict__
#elif _MSC_VER
#define RESTRICT __restrict
#else
#define RESTRICT
#endif
#if defined WALBERLA_CXX_COMPILER_IS_GNU || defined WALBERLA_CXX_COMPILER_IS_CLANG
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wunused-variable"
#pragma GCC diagnostic ignored "-Wunused-parameter"
#endif
namespace walberla
{
namespace lbm{
class D3Q19StorageSpecification
{
public:
// Used lattice stencil
using Stencil = stencil::D3Q19;
// Lattice stencil used for the communication (should be used to define which block directions need to be communicated)
using CommunicationStencil = stencil::D3Q19;
// If false used correction: Lattice Boltzmann Model for the Incompressible Navier–Stokes Equation, He 1997
static const bool compressible = false;
// Cut off for the lattice Boltzmann equilibrium
static const int equilibriumAccuracyOrder = 2;
// If true the equilibrium is computed in regard to "delta_rho" and not the actual density "rho"
static const bool equilibriumDeviationOnly = true;
// If streaming pattern is inplace (esotwist, aa, ...) or not (pull, push)
static const bool inplace = false;
// If true the background deviation (rho_0 = 1) is subtracted for the collision step.
static const bool zeroCenteredPDFs = true;
// Lattice weights
static constexpr double w[19] = { 0.333333333333333,0.0555555555555556,0.0555555555555556,0.0555555555555556,0.0555555555555556,0.0555555555555556,0.0555555555555556,0.0277777777777778,0.0277777777777778,0.0277777777777778,0.0277777777777778,0.0277777777777778,0.0277777777777778,0.0277777777777778,0.0277777777777778,0.0277777777777778,0.0277777777777778,0.0277777777777778,0.0277777777777778 };
// Inverse lattice weights
static constexpr double wInv[19] = { 3.00000000000000,18.0000000000000,18.0000000000000,18.0000000000000,18.0000000000000,18.0000000000000,18.0000000000000,36.0000000000000,36.0000000000000,36.0000000000000,36.0000000000000,36.0000000000000,36.0000000000000,36.0000000000000,36.0000000000000,36.0000000000000,36.0000000000000,36.0000000000000,36.0000000000000 };
// Compute kernels to pack and unpack MPI buffers
class PackKernels {
public:
using PdfField_T = field::GhostLayerField<double, 19>;
using value_type = typename PdfField_T::value_type;
static const bool inplace = false;
/**
* Packs all pdfs from the given cell interval to the send buffer.
* */
void packAll(PdfField_T * pdfs_src, CellInterval & ci, unsigned char * outBuffer) const;
/**
* Unpacks all pdfs from the send buffer to the given cell interval.
* */
void unpackAll(PdfField_T * pdfs_dst, CellInterval & ci, unsigned char * inBuffer) const;
/**
* Copies data between two blocks on the same process.
* All pdfs from the sending interval are copied onto the receiving interval.
* */
void localCopyAll(PdfField_T * pdfs_src, CellInterval & srcInterval, PdfField_T * pdfs_dst, CellInterval & dstInterval) const;
/**
* Packs only those populations streaming in directions aligned with the sending direction dir from the given cell interval.
* For example, in 2D, if dir == N, the pdfs streaming in directions NW, N, NE are packed.
* */
void packDirection(PdfField_T * pdfs_src, CellInterval & ci, unsigned char * outBuffer, stencil::Direction dir) const;
/**
* Unpacks only those populations streaming in directions aligned with the sending direction dir to the given cell interval.
* For example, in 2D, if dir == N, the pdfs streaming in directions NW, N, NE are unpacked.
* */
void unpackDirection(PdfField_T * pdfs_dst, CellInterval & ci, unsigned char * inBuffer, stencil::Direction dir) const;
/** Copies data between two blocks on the same process.
* PDFs streaming aligned with the direction dir are copied from the sending interval onto the receiving interval.
* */
void localCopyDirection(PdfField_T * pdfs_src, CellInterval & srcInterval, PdfField_T * pdfs_dst, CellInterval & dstInterval, stencil::Direction dir) const;
/**
* Returns the number of bytes that will be packed from / unpacked to the cell interval
* when using packDirection / unpackDirection
* @param ci The cell interval
* @param dir The communication direction
* @return The required size of the buffer, in bytes
* */
uint_t size (CellInterval & ci, stencil::Direction dir) const {
return ci.numCells() * sizes[dir] * sizeof(value_type);
}
/**
* Returns the number of bytes that will be packed from / unpacked to the cell interval
* when using packAll / unpackAll
* @param ci The cell interval
* @return The required size of the buffer, in bytes
* */
uint_t size (CellInterval & ci) const {
return ci.numCells() * 19 * sizeof(value_type);
}
private:
const uint_t sizes[27] { 0, 5, 5, 5, 5, 5, 5, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0 };
};
};
}} //lbm/walberla