vide_public/external/healpix/cxxsupport/trafos.h
2012-10-30 13:56:48 -04:00

103 lines
3.6 KiB
C++

/*
* This file is part of libcxxsupport.
*
* libcxxsupport is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* libcxxsupport is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with libcxxsupport; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
/*
* libcxxsupport is being developed at the Max-Planck-Institut fuer Astrophysik
* and financially supported by the Deutsches Zentrum fuer Luft- und Raumfahrt
* (DLR).
*/
/*! \file trafos.h
* Celestial coordinate transformations.
*
* Copyright (C) 2005 Max-Planck-Society
* \author Martin Reinecke
*/
#ifndef PLANCK_TRAFOS_H
#define PLANCK_TRAFOS_H
#include "vec3.h"
#include "pointing.h"
#include "rotmatrix.h"
#include "cxxutils.h"
#include "geom_utils.h"
enum coordsys { Ecliptic, Equatorial, Galactic };
/*! Class for celestial coordinate transformations. */
class Trafo
{
private:
rotmatrix mat;
static vec3 xcc_dp_precess (const vec3 &iv, double iepoch, double oepoch);
static double get_epsilon (double epoch);
static vec3 xcc_dp_e_to_q (const vec3 &iv, double epoch);
static vec3 xcc_dp_q_to_e (const vec3 &iv, double epoch);
static vec3 xcc_dp_g_to_e (const vec3 &iv, double epoch);
static vec3 xcc_dp_e_to_g (const vec3 &iv, double epoch);
static vec3 xcc_v_convert(const vec3 &iv, double iepoch, double oepoch,
coordsys isys,coordsys osys);
static void coordsys2matrix (double iepoch, double oepoch, coordsys isys,
coordsys osys, rotmatrix &matrix);
public:
/*! Creates a \a Trafo for transformation from \a iepoch and \a isys
to \a oepoch and \a osys. */
Trafo (double iepoch, double oepoch, coordsys isys, coordsys osys)
{ coordsys2matrix (iepoch, oepoch, isys, osys, mat); }
/*! Transforms the vector \a vec and returns the result. */
vec3 operator() (const vec3 &vec) const
{ return mat.Transform(vec); }
/*! Transforms the pointing \a ptg and returns the result. */
pointing operator() (const pointing &ptg) const
{ return pointing(operator()(vec3(ptg))); }
/*! Transforms the pointing \a ptg and returns it in \a newptg.
On exit, \a delta_psi holds the change in orientation. */
void rotatefull (const pointing &ptg, pointing &newptg,
double &delta_psi) const
{
const double halfpi_=1.570796326794896619231321691639751442099;
vec3 vec (ptg);
vec3 east (-vec.y,vec.x,0.);
vec3 newvec = operator()(vec);
vec3 neweast = operator()(east);
delta_psi = orientation(newvec,neweast)+halfpi_;
newptg = newvec;
}
/*! Transforms the vector \a vec and returns it in \a newvec.
On exit, \a delta_psi holds the change in orientation. */
void rotatefull (const vec3 &vec, vec3 &newvec, double &delta_psi) const
{
const double halfpi_=1.570796326794896619231321691639751442099;
vec3 east (-vec.y,vec.x,0.);
newvec = operator()(vec);
vec3 neweast = operator()(east);
delta_psi = orientation(newvec,neweast)+halfpi_;
}
/*! Returns the internally used rotation matrix. */
const rotmatrix &Matrix() const
{ return mat; }
};
#endif