#include "structs.h"
#include "mymath.h"

void shift_psf (struct image psf, struct image *tpsf, float dx, float dy);
double **fftpsf (struct image psf, long model_naxes[], int add0pad,
    long complex_naxes[]);

double **get_fftpsf (struct fitpars *fpar, struct image model, struct image psf,
    long complex_naxes[])
{
    extern struct image tpsf;
    extern struct inpars input;

    int os;
    float xos, yos, dx, dy;
    double **psfft;

    os = input.sampfac;

    xos = fpar->a[1] * os - 0.5*(os-1);
    yos = fpar->a[2] * os - 0.5*(os-1);
    dx = xos - NINT(xos);
    dy = yos - NINT(yos);

    shift_psf (psf, &tpsf, dx, dy);
    psfft = fftpsf (tpsf, model.naxes, 0, complex_naxes);

    return (psfft);
};