stencil_type.hpp

/*
 * stencil_type.hpp
 *
 *  Created on: Jun 25, 2017
 *      Author: i-bird
 */

#ifndef OPENFPM_DATA_SRC_GRID_ITERATORS_STENCIL_TYPE_HPP_
#define OPENFPM_DATA_SRC_GRID_ITERATORS_STENCIL_TYPE_HPP_

template<unsigned int dim, unsigned int Np>
struct stencil_offset_compute
{
    static const unsigned int nsp = Np;

    long int stencil_offset[Np];

    grid_key_dx<dim> stencil_pnt[Np];


    template<unsigned int dim2> void set_stencil(const grid_key_dx<dim2> (& stencil_pnt)[Np])
    {
        for (size_t i = 0 ; i < Np ; i++)
        {this->stencil_pnt[i] = stencil_pnt[i];}
    }

    template<unsigned int id> size_t getStencil() const
    {
        return stencil_offset[id];
    }

    template<unsigned int dim2, typename ginfo>
    inline void calc_offsets(const ginfo & g,
                             const grid_key_dx<dim2> & start_p)
    {
        for (size_t i = 0 ; i < Np ; i++)
        {
            grid_key_dx<dim2> zero;
            zero = start_p + stencil_pnt[i];

            stencil_offset[i] = g.LinId(zero);
        }
    }

    template<unsigned int dim2,typename ginfo>
    inline void calc_offsets(const ginfo & g,
                             const grid_key_dx<dim2> & start_p,
                             const grid_key_dx<dim2> (& stencil_pnt)[Np])
    {
        for (size_t i = 0 ; i < Np ; i++)
        {
            grid_key_dx<dim2> offset_point;
            this->stencil_pnt[i] = stencil_pnt[i];
            offset_point = start_p + stencil_pnt[i];
            stencil_offset[i] = g.LinId(offset_point);
        }
    }

    inline void increment()
    {
        // update the offsets
        for (size_t i = 0 ; i < Np ; i++)
            stencil_offset[i] += 1;
    }

    template<typename ginfo> inline void adjust_offset(size_t i, size_t idr, const ginfo & grid_base)
    {
        size_t str_dw = (i == 0)?1:grid_base.size_s(i-1);

        // update the offsets
        for (size_t k = 0 ; k < Np ; k++)
        {stencil_offset[k] += -str_dw*idr + grid_base.size_s(i);}
    }

    template<unsigned int tot_add>
    inline void private_sum()
    {
        for (size_t i = 0 ; i < Np ; i++)
        {stencil_offset[i] += tot_add;}
    }

    inline void private_adjust(size_t tot_add)
    {
        for (size_t i = 0 ; i < Np ; i++)
        {stencil_offset[i] += tot_add;}
    }

};

struct no_stencil
{
    static const unsigned int nsp = 1;

    template<unsigned int id> size_t getStencil() const
    {return 0;}


    template<unsigned int dim2, typename ginfo>
    inline void calc_offsets(const ginfo & g,
                             const grid_key_dx<dim2> & start_p)
    {}

    inline void increment()
    {}

    template<unsigned int dim2> void set_stencil(const grid_key_dx<dim2> (& stencil_pnt)[1])
    {
    }

    template<typename ginfo> inline void adjust_offset(size_t i, size_t idr, const ginfo & grid_base)
    {}
};



#endif /* OPENFPM_DATA_SRC_GRID_ITERATORS_STENCIL_TYPE_HPP_ */