main.cu

#include "Grid/grid_dist_id.hpp"
#include "data_type/aggregate.hpp"
#include "timer.hpp"

#ifdef __NVCC__

constexpr int U = 0;
constexpr int V = 1;

constexpr int U_next = 2;
constexpr int V_next = 3;

constexpr int x = 0;
constexpr int y = 1;
constexpr int z = 2;


typedef sgrid_dist_id_gpu<3,float,aggregate<float,float,float,float> > SparseGridType;


void init(SparseGridType & grid, Box<3,float> & domain)
{

    typedef typename GetAddBlockType<SparseGridType>::type InsertBlockT;

    grid.addPoints([] __device__ (int i, int j, int k)
                    {
                        return true;
                    },
                    [] __device__ (InsertBlockT & data, int i, int j, int k)
                    {
                        data.template get<U>() = 1.0;
                        data.template get<V>() = 0.0;
                    }
                    );


    grid.template flush<smax_<U>,smax_<V>>(flush_type::FLUSH_ON_DEVICE);


    long int x_start = grid.size(0)*1.55f/domain.getHigh(0);
    long int y_start = grid.size(1)*1.55f/domain.getHigh(1);
    long int z_start = grid.size(1)*1.55f/domain.getHigh(2);

    long int x_stop = grid.size(0)*1.85f/domain.getHigh(0);
    long int y_stop = grid.size(1)*1.85f/domain.getHigh(1);
    long int z_stop = grid.size(1)*1.85f/domain.getHigh(2);


    grid_key_dx<3> start({x_start,y_start,z_start});
    grid_key_dx<3> stop ({x_stop,y_stop,z_stop});

        grid.addPoints(start,stop,[] __device__ (int i, int j, int k)
                                {
                                                return true;
                                },
                                [] __device__ (InsertBlockT & data, int i, int j, int k)
                                {
                                        data.template get<U>() = 0.5;
                                        data.template get<V>() = 0.24;
                                }
                                );

    grid.template flush<smax_<U>,smax_<V>>(flush_type::FLUSH_ON_DEVICE);

}


int main(int argc, char* argv[])
{
    openfpm_init(&argc,&argv);

    // domain
    Box<3,float> domain({0.0,0.0,0.0},{2.5,2.5,2.5});
    
    // grid size
        size_t sz[3] = {256,256,256};

    // Define periodicity of the grid
    periodicity<3> bc = {PERIODIC,PERIODIC,PERIODIC};
    
    // Ghost in grid unit
    Ghost<3,long int> g(1);
    
    // deltaT
    float deltaT = 0.25;

    // Diffusion constant for specie U
    float du = 2*1e-5;

    // Diffusion constant for specie V
    float dv = 1*1e-5;

    // Number of timesteps
#ifdef TEST_RUN
    size_t timeSteps = 300;
#else
        size_t timeSteps = 15000;
#endif

    // K and F (Physical constant in the equation)
    float K = 0.053;
    float F = 0.014;

    sgrid_dist_id_gpu<3, float, aggregate<float,float,float,float>> grid(sz,domain,g,bc);

    // spacing of the grid on x and y
    float spacing[3] = {grid.spacing(0),grid.spacing(1),grid.spacing(2)};

    init(grid,domain);

    // sync the ghost
    grid.template ghost_get<U,V>(RUN_ON_DEVICE);

    // because we assume that spacing[x] == spacing[y] we use formula 2
    // and we calculate the prefactor of Eq 2
    float uFactor = deltaT * du/(spacing[x]*spacing[x]);
    float vFactor = deltaT * dv/(spacing[x]*spacing[x]);

    auto & v_cl = create_vcluster();

    timer tot_sim;
    tot_sim.start();

    for (size_t i = 0; i < timeSteps ; ++i)
    {
        if (v_cl.rank() == 0)
        {std::cout << "STEP: " << i << std::endl;}
/*      if (i % 300 == 0)
        {
            std::cout << "STEP: " << i << std::endl;
            grid.write_frame("out",i,VTK_WRITER);
        }*/


        typedef typename GetCpBlockType<decltype(grid),0,1>::type CpBlockType;


        auto func = [uFactor,vFactor,deltaT,F,K] __device__ (float & u_out, float & v_out,
                                                   CpBlockType & u, CpBlockType & v,
                                                   int i, int j, int k){

                float uc = u(i,j,k);
                float vc = v(i,j,k);

                u_out = uc + uFactor *(u(i-1,j,k) + u(i+1,j,k) +
                                                       u(i,j-1,k) + u(i,j+1,k) +
                                                       u(i,j,k-1) + u(i,j,k+1) - 6.0*uc) - deltaT * uc*vc*vc
                                                       - deltaT * F * (uc - 1.0);


                v_out = vc + vFactor *(v(i-1,j,k) + v(i+1,j,k) +
                                                       v(i,j+1,k) + v(i,j-1,k) +
                                                       v(i,j,k-1) + v(i,j,k+1) - 6.0*vc) + deltaT * uc*vc*vc
                                   - deltaT * (F+K) * vc;
                };



        if (i % 2 == 0)
        {
            grid.conv2<U,V,U_next,V_next,1>({0,0,0},{(long int)sz[0]-1,(long int)sz[1]-1,(long int)sz[2]-1},func);

            // After copy we synchronize again the ghost part U and V

            grid.ghost_get<U_next,V_next>(RUN_ON_DEVICE | SKIP_LABELLING);
        }
        else
        {
            grid.conv2<U_next,V_next,U,V,1>({0,0,0},{(long int)sz[0]-1,(long int)sz[1]-1,(long int)sz[2]-1},func);

            // After copy we synchronize again the ghost part U and V
            grid.ghost_get<U,V>(RUN_ON_DEVICE | SKIP_LABELLING);
        }


        // Every 500 time step we output the configuration for
        // visualization
//      if (i % 500 == 0)
//      {
//          grid.save("output_" + std::to_string(count));
//          count++;
//      }
    }
    
    tot_sim.stop();
    std::cout << "Total simulation: " << tot_sim.getwct() << std::endl;

    grid.deviceToHost<U,V,U_next,V_next>();
    grid.write("final");



    openfpm_finalize();


}

#else

int main(int argc, char* argv[])
{
        return 0;
}

#endif