grid_key_dx_iterator_hilbert.hpp

/*
 * grid_key_dx_iterator_hilbert.hpp
 *
 *  Created on: Feb 24, 2016
 *      Author: yaroslav
 */
 
#ifndef OPENFPM_DATA_SRC_GRID_GRID_KEY_DX_ITERATOR_HILBERT_HPP_
#define OPENFPM_DATA_SRC_GRID_GRID_KEY_DX_ITERATOR_HILBERT_HPP_
 
extern "C"
{
#include "hilbertKey.h"
}
 
 
/*
 *
 * Grid key class iterator, iterate through the grid elements following an
 * hilbert space filling curve
 *
 * \param dim dimensionality of the grid
 *
 * ### Grid iterator declaration and usage
 * \snippet grid_unit_tests.hpp Grid iterator test usage
 *
 */
 
template<unsigned int dim>
class grid_key_dx_iterator_hilbert
{
#ifdef SE_CLASS1
    bool initialized = false;
#endif
 
    uint64_t hkey = 0;
 
    size_t m;
 
    grid_sm<dim,void> grid_base;
 
protected:
 
    grid_key_dx<dim> gk;
 
public:
 
    grid_key_dx_iterator_hilbert(int32_t m)
    :m(m)
    {
        // create from m the correct grid_sm
 
        size_t dims[dim];
 
        //Set the 2^m value to the each elements of dims[]
        for (size_t i = 0 ; i < dim ; i++)
            dims[i] = 1 << m;
 
        //Set grid_sm dimensions
        grid_base.setDimensions(dims);
 
        reset();
 
#ifdef SE_CLASS1
        initialized = true;
#endif
    }
 
    grid_key_dx_iterator_hilbert<dim> & operator++()
    {
        //An integer to handle errors
        int err;
 
        hkey++;
 
        //Array to handle output
        uint64_t nextCoord[dim];
 
        //Get the coordinates of the next cell
        getIntCoordFromHKey(nextCoord, m, dim, hkey, &err);
 
        //Set the new coordinates
        for (size_t i = 0; i < dim; i++)
            gk.set_d(i, nextCoord[i]);
 
        return *this;
    }
 
    bool isNext()
    {
        if ( hkey < (size_t)1 << (m*dim))
        {
 
            return true;
        }
 
        return false;
    }
 
    const grid_key_dx<dim> & get()
    {
        return gk;
    }
 
 
    void reset()
    {
        for (size_t i = 0 ; i < dim ; i++)
            gk.set_d(i,0);
    }
};
 
 
#endif /* OPENFPM_DATA_SRC_GRID_GRID_KEY_DX_ITERATOR_HILBERT_HPP_ */