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/*
* diffraction.c
*
* Calculate diffraction patterns by Fourier methods
*
* (c) 2007-2009 Thomas White <thomas.white@desy.de>
*
* pattern_sim - Simulate diffraction patterns from small crystals
*
*/
#include <stdlib.h>
#include <math.h>
#include <stdio.h>
#include "image.h"
#include "utils.h"
#include "cell.h"
static void mapping_rotate(double x, double y, double z,
double *ddx, double *ddy, double *ddz,
double omega, double tilt)
{
double nx, ny, nz;
double x_temp, y_temp, z_temp;
/* First: rotate image clockwise until tilt axis is aligned
* horizontally. */
nx = x*cos(omega) + y*sin(omega);
ny = -x*sin(omega) + y*cos(omega);
nz = z;
/* Now, tilt about the x-axis ANTICLOCKWISE around +x, i.e. the
* "wrong" way. This is because the crystal is rotated in the
* experiment, not the Ewald sphere. */
x_temp = nx; y_temp = ny; z_temp = nz;
nx = x_temp;
ny = cos(tilt)*y_temp + sin(tilt)*z_temp;
nz = -sin(tilt)*y_temp + cos(tilt)*z_temp;
/* Finally, reverse the omega rotation to restore the location of the
* image in 3D space */
x_temp = nx; y_temp = ny; z_temp = nz;
nx = x_temp*cos(-omega) + y_temp*sin(-omega);
ny = -x_temp*sin(-omega) + y_temp*cos(-omega);
nz = z_temp;
*ddx = nx;
*ddy = ny;
*ddz = nz;
}
void get_diffraction(struct image *image, UnitCell *cell)
{
}
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