vec_rotate()

void vec_rotate	(	struct vector *	v,
		DOUBLE	phi,
		DOUBLE	theta,
		DOUBLE	psi
	)

Rotates a vector with three angles. The original vector is overwritten.

Parameters

[in,out]	v
[in]	phi
[in]	theta
[in]	psi

                                                                      {

  DOUBLE m11,m12,m13;
  DOUBLE m21,m22,m23;
  DOUBLE m31,m32,m33;
  struct vector vtmp;

  m11 = COS(theta)*COS(psi);
  m12 = -COS(phi)*SIN(psi) + SIN(phi)*SIN(theta)*COS(psi);
  m13 = SIN(phi)*SIN(psi) + COS(phi)* SIN(theta)*COS(psi);

  m21 = COS(theta)*SIN(psi);
  m22 = COS(phi)*COS(psi) + SIN(phi)*SIN(theta)*SIN(psi);
  m23 = -SIN(phi)*COS(psi) + COS(phi)*SIN(theta)*SIN(psi);

  m31 = -SIN(theta);
  m32 = SIN(phi) * COS(theta);
  m33 = COS(phi) * COS(theta);

  vtmp.x = m11* v->x +  m12*v->y + m13*v->z;
  vtmp.y = m21* v->x +  m22*v->y + m23*v->z;
  vtmp.z = m31* v->x +  m32*v->y + m33*v->z;

  v->x = vtmp.x;
  v->y = vtmp.y;
  v->z = vtmp.z;
}