FUnifTensorialKernel.hpp 12.7 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
// ===================================================================================
// Copyright ScalFmm 2011 INRIA, Olivier Coulaud, Bérenger Bramas, Matthias Messner
// olivier.coulaud@inria.fr, berenger.bramas@inria.fr
// This software is a computer program whose purpose is to compute the FMM.
//
// This software is governed by the CeCILL-C and LGPL licenses and
// abiding by the rules of distribution of free software.
//
// This program 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 and CeCILL-C Licenses for more details.
// "http://www.cecill.info".
// "http://www.gnu.org/licenses".
// ===================================================================================
16 17 18
// Keep in private GIT
// @SCALFMM_PRIVATE

19 20 21 22
#ifndef FUNIFTENSORIALKERNEL_HPP
#define FUNIFTENSORIALKERNEL_HPP

#include "../../Utils/FGlobal.hpp"
23

24 25 26
#include "../../Utils/FSmartPointer.hpp"

#include "./FAbstractUnifKernel.hpp"
27 28
#include "./FUnifM2LHandler.hpp"
#include "./FUnifTensorialM2LHandler.hpp" //PB: temporary version
29 30 31 32 33 34 35 36 37 38 39 40 41 42 43

class FTreeCoordinate;

/**
 * @author Pierre Blanchard (pierre.blanchard@inria.fr)
 * @class FUnifTensorialKernel
 * @brief
 * Please read the license
 *
 * This kernels implement the Lagrange interpolation based FMM operators. It
 * implements all interfaces (P2P,P2M,M2M,M2L,L2L,L2P) which are required by
 * the FFmmAlgorithm and FFmmAlgorithmThread.
 *
 * PB: 3 IMPORTANT remarks !!!
 *
44 45
 * 1) Handling tensorial kernels (DIM,NRHS,NLHS) and having multiple rhs 
 * (NVALS) are considered 2 distinct features and are currently combined.
46
 *
47 48 49 50 51 52
 * 2) When it comes to applying M2L it is NOT much faster to loop over 
 * NRHSxNLHS inside applyM2L (at least for the Lagrange case).
 * 2-bis) During precomputation the tensorial matrix kernels are evaluated 
 * blockwise, but this is not always possible. 
 * In fact, in the ChebyshevSym variant the matrix kernel needs to be 
 * evaluated compo-by-compo since we currently use a scalar ACA.
53
 *
54 55 56
 * 3) We currently use multiple 1D FFT instead of multidim FFT since embedding
 * is circulant. Multidim FFT could be used if embedding were block circulant.
 * TODO investigate possibility of block circulant embedding
57 58 59 60 61 62
 *
 * @tparam CellClass Type of cell
 * @tparam ContainerClass Type of container to store particles
 * @tparam MatrixKernelClass Type of matrix kernel function
 * @tparam ORDER Lagrange interpolation order
 */
63
template < class FReal, class CellClass, class ContainerClass,   class MatrixKernelClass, int ORDER, int NVALS = 1>
64
class FUnifTensorialKernel
65
    : public FAbstractUnifKernel<FReal, CellClass, ContainerClass, MatrixKernelClass, ORDER, NVALS>
66
{
67 68 69 70
    enum {nRhs = MatrixKernelClass::NRHS,
          nLhs = MatrixKernelClass::NLHS,
          nPot = MatrixKernelClass::NPOT,
          nPV = MatrixKernelClass::NPV};
71 72 73

protected://PB: for OptiDis

74
    // private types
75
    typedef FUnifTensorialM2LHandler<FReal, ORDER,MatrixKernelClass,MatrixKernelClass::Type> M2LHandlerClass;
76

77
    // using from
78
    typedef FAbstractUnifKernel< FReal, CellClass, ContainerClass, MatrixKernelClass, ORDER, NVALS>
79
    AbstractBaseClass;
80

81 82
    /// Needed for P2P and M2L operators
    const MatrixKernelClass *const MatrixKernel;
83

84 85
    /// Needed for M2L operator
    const M2LHandlerClass M2LHandler;
86

87 88 89
    /// Leaf level separation criterion
    const int LeafLevelSeparationCriterion;

90
public:
91 92 93 94 95 96 97
    /**
     * The constructor initializes all constant attributes and it reads the
     * precomputed and compressed M2L operators from a binary file (an
     * runtime_error is thrown if the required file is not valid).
     */
    FUnifTensorialKernel(const int inTreeHeight,
                         const FReal inBoxWidth,
98
                         const FPoint<FReal>& inBoxCenter,
99
                         const MatrixKernelClass *const inMatrixKernel,
100 101
                         const FReal inBoxWidthExtension,
                         const int inLeafLevelSeparationCriterion = 1)
102
    : FAbstractUnifKernel< FReal, CellClass, ContainerClass, MatrixKernelClass, ORDER, NVALS>(inTreeHeight,inBoxWidth,inBoxCenter,inBoxWidthExtension),
103 104
      MatrixKernel(inMatrixKernel),
      M2LHandler(MatrixKernel,
105
                 inTreeHeight,
106
                 inBoxWidth,
107 108 109
                 inBoxWidthExtension,
                 inLeafLevelSeparationCriterion), 
      LeafLevelSeparationCriterion(inLeafLevelSeparationCriterion)
110 111 112 113 114 115
    { }


    void P2M(CellClass* const LeafCell,
             const ContainerClass* const SourceParticles)
    {
116
        const FPoint<FReal> LeafCellCenter(AbstractBaseClass::getLeafCellCenter(LeafCell->getCoordinate()));
117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132
        const FReal ExtendedLeafCellWidth(AbstractBaseClass::BoxWidthLeaf 
                                          + AbstractBaseClass::BoxWidthExtension);

        for(int idxV = 0 ; idxV < NVALS ; ++idxV){

            // 1) apply Sy
            AbstractBaseClass::Interpolator->applyP2M(LeafCellCenter, ExtendedLeafCellWidth,
                                                      LeafCell->getMultipole(idxV*nRhs), SourceParticles);

            for(int idxRhs = 0 ; idxRhs < nRhs ; ++idxRhs){
                // update multipole index
                int idxMul = idxV*nRhs + idxRhs;

                // 2) apply Discrete Fourier Transform
                M2LHandler.applyZeroPaddingAndDFT(LeafCell->getMultipole(idxMul), 
                                                  LeafCell->getTransformedMultipole(idxMul));
133

134
            }
135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165
        }// NVALS
    }


    void M2M(CellClass* const FRestrict ParentCell,
             const CellClass*const FRestrict *const FRestrict ChildCells,
             const int TreeLevel)
    {
        for(int idxV = 0 ; idxV < NVALS ; ++idxV){
            for(int idxRhs = 0 ; idxRhs < nRhs ; ++idxRhs){
                // update multipole index
                int idxMul = idxV*nRhs + idxRhs;

                // 1) apply Sy
                FBlas::scal(AbstractBaseClass::nnodes, FReal(0.), ParentCell->getMultipole(idxMul));
                for (unsigned int ChildIndex=0; ChildIndex < 8; ++ChildIndex){
                    if (ChildCells[ChildIndex]){
                        AbstractBaseClass::Interpolator->applyM2M(ChildIndex, 
                                                                  ChildCells[ChildIndex]->getMultipole(idxMul),
                                                                  ParentCell->getMultipole(idxMul), 
                                                                  TreeLevel/*Cell width extension specific*/);
                    }
                }
                // 2) Apply Discete Fourier Transform
                M2LHandler.applyZeroPaddingAndDFT(ParentCell->getMultipole(idxMul), 
                                                  ParentCell->getTransformedMultipole(idxMul));
            }
        }// NVALS
    }


166 167
    void M2L(CellClass* const FRestrict TargetCell, const CellClass* SourceCells[],
             const int neighborPositions[], const int inSize, const int TreeLevel)  override {
168 169 170 171 172 173 174 175 176 177 178
        const FReal CellWidth(AbstractBaseClass::BoxWidth / FReal(FMath::pow(2, TreeLevel)));
        const FReal ExtendedCellWidth(CellWidth + AbstractBaseClass::BoxWidthExtension);
        const FReal scale(MatrixKernel->getScaleFactor(ExtendedCellWidth));

        for(int idxV = 0 ; idxV < NVALS ; ++idxV){
            for (int idxLhs=0; idxLhs < nLhs; ++idxLhs){

                // update local index
                const int idxLoc = idxV*nLhs + idxLhs;

                // load transformed local expansion
179
                FComplex<FReal> *const TransformedLocalExpansion = TargetCell->getTransformedLocal(idxLoc);
180 181 182 183 184 185 186 187 188 189

                // update idxRhs
                const int idxRhs = idxLhs % nPV; 

                // update multipole index
                const int idxMul = idxV*nRhs + idxRhs;

                // get index in matrix kernel
                const unsigned int d = MatrixKernel->getPosition(idxLhs);

190 191
                for(int idxExistingNeigh = 0 ; idxExistingNeigh < inSize ; ++idxExistingNeigh){
                    const int idx = neighborPositions[idxExistingNeigh];
192

193 194 195
                    M2LHandler.applyFC(idx, TreeLevel, scale, d,
                                       SourceCells[idxExistingNeigh]->getTransformedMultipole(idxMul),
                                       TransformedLocalExpansion);
196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228

                }
            }// NLHS=NPOT*NPV
        }// NVALS
    }


    void L2L(const CellClass* const FRestrict ParentCell,
             CellClass* FRestrict *const FRestrict ChildCells,
             const int TreeLevel)
    {
        for(int idxV = 0 ; idxV < NVALS ; ++idxV){
            for(int idxLhs = 0 ; idxLhs < nLhs ; ++idxLhs){
                int idxLoc = idxV*nLhs + idxLhs;
                // 1) Apply Inverse Discete Fourier Transform
                M2LHandler.unapplyZeroPaddingAndDFT(ParentCell->getTransformedLocal(idxLoc),
                                                    const_cast<CellClass*>(ParentCell)->getLocal(idxLoc));
                // 2) apply Sx
                for (unsigned int ChildIndex=0; ChildIndex < 8; ++ChildIndex){
                    if (ChildCells[ChildIndex]){
                        AbstractBaseClass::Interpolator->applyL2L(ChildIndex, 
                                                                  ParentCell->getLocal(idxLoc), 
                                                                  ChildCells[ChildIndex]->getLocal(idxLoc),
                                                                  TreeLevel/*Cell width extension specific*/);
                    }
                }
            }
        }// NVALS
    }

    void L2P(const CellClass* const LeafCell,
             ContainerClass* const TargetParticles)
    {
229
        const FPoint<FReal> LeafCellCenter(AbstractBaseClass::getLeafCellCenter(LeafCell->getCoordinate()));
230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252
        const FReal ExtendedLeafCellWidth(AbstractBaseClass::BoxWidthLeaf 
                                          + AbstractBaseClass::BoxWidthExtension);

        for(int idxV = 0 ; idxV < NVALS ; ++idxV){
            for(int idxLhs = 0 ; idxLhs < nLhs ; ++idxLhs){
                int idxLoc = idxV*nLhs + idxLhs;
                // 1)  Apply Inverse Discete Fourier Transform
                M2LHandler.unapplyZeroPaddingAndDFT(LeafCell->getTransformedLocal(idxLoc), 
                                                    const_cast<CellClass*>(LeafCell)->getLocal(idxLoc));

            }

            // 2.a) apply Sx
            AbstractBaseClass::Interpolator->applyL2P(LeafCellCenter, ExtendedLeafCellWidth,
                                                      LeafCell->getLocal(idxV*nLhs), TargetParticles);

            // 2.b) apply Px (grad Sx)
            AbstractBaseClass::Interpolator->applyL2PGradient(LeafCellCenter, ExtendedLeafCellWidth,
                                                              LeafCell->getLocal(idxV*nLhs), TargetParticles);

        }// NVALS
    }

253
    void P2P(const FTreeCoordinate& inPosition,
254
             ContainerClass* const FRestrict inTargets, const ContainerClass* const FRestrict inSources,
255 256
             ContainerClass* const inNeighbors[], const int neighborPositions[],
             const int inSize) override {
257 258 259 260 261 262 263 264 265
        if(inTargets == inSources){
            P2POuter(inPosition, inTargets, inNeighbors, neighborPositions, inSize);
            DirectInteractionComputer<FReal, MatrixKernelClass::NCMP, NVALS>::P2PInner(inTargets,MatrixKernel);
        }
        else{
            const ContainerClass* const srcPtr[1] = {inSources};
            DirectInteractionComputer<FReal, MatrixKernelClass::NCMP, NVALS>::P2PRemote(inTargets,srcPtr,1,MatrixKernel);
            DirectInteractionComputer<FReal, MatrixKernelClass::NCMP, NVALS>::P2PRemote(inTargets,inNeighbors,inSize,MatrixKernel);
        }
266 267 268 269 270 271
    }

    void P2POuter(const FTreeCoordinate& /*inLeafPosition*/,
             ContainerClass* const FRestrict inTargets,
             ContainerClass* const inNeighbors[], const int neighborPositions[],
             const int inSize) override {
272 273 274 275 276 277
        int nbNeighborsToCompute = 0;
        while(nbNeighborsToCompute < inSize
              && neighborPositions[nbNeighborsToCompute] < 14){
            nbNeighborsToCompute += 1;
        }
        DirectInteractionComputer<FReal, MatrixKernelClass::NCMP, NVALS>::P2P(inTargets,inNeighbors,nbNeighborsToCompute,MatrixKernel);
278 279 280 281 282
    }


    void P2PRemote(const FTreeCoordinate& /*inPosition*/,
                   ContainerClass* const FRestrict inTargets, const ContainerClass* const FRestrict /*inSources*/,
283 284 285
                   ContainerClass* const inNeighbors[], const int /*neighborPositions*/[],
                   const int inSize) override {
        DirectInteractionComputer<FReal, MatrixKernelClass::NCMP, NVALS>::P2PRemote(inTargets,inNeighbors,inSize,MatrixKernel);
286
    }
287 288 289 290

};


291
#endif //FUNIFTENSORIALKERNEL_HPP
292 293

// [--END--]