Imported healpix tree

external/healpix/cxxsupport/trafos.h

@@ -0,0 +1,103 @@
+/*
+ *  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