#include <math.h>
#include "transform.h"
#include "Constants.h"

vtr RDirection(double theta, double phi)
{
  double theta_in_rad, phi_in_rad;

  theta_in_rad = theta * Pi / 180.0;
  phi_in_rad = phi * Pi / 180.0;
  
  vtr vv(sin(theta_in_rad) * cos(phi_in_rad),
	 sin(theta_in_rad) * sin(phi_in_rad),
	 cos(theta_in_rad));

  return vv;
}

vtr ThetaDirection(double theta, double phi)
{
  double theta_in_rad, phi_in_rad;

  theta_in_rad = theta * Pi / 180.0;
  phi_in_rad = phi * Pi / 180.0;
  
  vtr vv(cos(theta_in_rad) * cos(phi_in_rad),
	 cos(theta_in_rad) * sin(phi_in_rad),
	 -sin(theta_in_rad));

  return vv;
}

vtr PhiDirection(double theta, double phi)
{
  double theta_in_rad, phi_in_rad;

  phi_in_rad = phi * Pi / 180.0;
  
  vtr vv(-sin(phi_in_rad),
	 cos(phi_in_rad),
	 0.0);

  return vv;
}