Index: trunk/MagicSoft/Mars/mastro/MAstroSky2Local.cc
===================================================================
--- trunk/MagicSoft/Mars/mastro/MAstroSky2Local.cc	(revision 3533)
+++ trunk/MagicSoft/Mars/mastro/MAstroSky2Local.cc	(revision 3533)
@@ -0,0 +1,133 @@
+/* ======================================================================== *\
+!
+! *
+! * This file is part of MARS, the MAGIC Analysis and Reconstruction
+! * Software. It is distributed to you in the hope that it can be a useful
+! * and timesaving tool in analysing Data of imaging Cerenkov telescopes.
+! * It is distributed WITHOUT ANY WARRANTY.
+! *
+! * Permission to use, copy, modify and distribute this software and its
+! * documentation for any purpose is hereby granted without fee,
+! * provided that the above copyright notice appear in all copies and
+! * that both that copyright notice and this permission notice appear
+! * in supporting documentation. It is provided "as is" without express
+! * or implied warranty.
+! *
+!
+!
+!   Author(s): Thomas Bretz, 11/2003 <mailto:tbretz@astro.uni-wuerzburg.de>
+!
+!   Copyright: MAGIC Software Development, 2000-2004
+!
+!
+\* ======================================================================== */
+
+/////////////////////////////////////////////////////////////////////////////
+//
+// MAstroSky2Local
+// ---------------
+//
+// Rotation Matrix to convert sky coordinates to ideal local coordinates
+// for example:
+//
+//   const Double_t ra  = MAstro::Hms2Rad(5, 34, 31.9);
+//   const Double_t dec = MAstro::Dms2Rad(22, 0, 52.0);
+//
+//   MTime time;
+//   time.Set(2004, 1, 26, 00, 20, 00);
+//
+//   MObservatory obs(MObservatory::kMagic1);
+//
+//   TVector3 v;
+//   v.SetMagThetaPhi(1, TMath::Pi()/2-dec, ra);
+//
+//   v *= MAstroSky2Local(time, obs);
+//
+//   Double_t azimuth   = v.Phi();
+//   Double_t zdistance = v.Theta();
+//
+////////////////////////////////////////////////////////////////////////////
+#include "MAstroSky2Local.h"
+
+#include "MTime.h"
+#include "MObservatory.h"
+
+using namespace std;
+
+ClassImp(MAstroSky2Local);
+
+// --------------------------------------------------------------------------
+//
+// Initialize the rotation matrix R as:
+//
+//   R = A*B*C*D
+//
+// with
+//
+//       |1  0  0|
+//   A = |0 -1  0|    (Change counting direction of rotation angle)
+//       |0  0  1|
+//
+//   B = RotZ(r1)     (Change rotation angle such, that phi=0 is identical
+//                     for both coordinate systems)
+//
+//   C = RotY(r2)     (Make zenith and sky pole the same point)
+//
+//   D = RotZ(180deg) (Align rottaion angle to N=0, E=90)
+//
+// with
+//
+//   r1 = gmst + longitude   with   gmst fraction of day, see MTime::GetGmst
+//                                  logitude of observers location
+//
+//   r2 = latitude-90deg     with   latitude of observers location
+//
+void MAstroSky2Local::Init(Double_t gmst, const MObservatory &obs)
+{
+    RotateZ(gmst + obs.GetElong());
+    RotateY(obs.GetPhi()-TMath::Pi()/2);
+    RotateZ(TMath::Pi());
+}
+
+// --------------------------------------------------------------------------
+//
+// Initialize MAstroSky2Local for a given time an a defined observatory
+// For more information see class description
+// For more information about gmst see MTime::GetGmst()
+//
+MAstroSky2Local::MAstroSky2Local(Double_t gmst, const MObservatory &obs) : TRotation(1, 0, 0, 0, -1, 0, 0, 0, 1)
+{
+    Init(gmst, obs);
+}
+
+// --------------------------------------------------------------------------
+//
+// Initialize MAstroSky2Local for a given time an a defined observatory
+// For more information see class description
+//
+MAstroSky2Local::MAstroSky2Local(const MTime &t, const MObservatory &obs) : TRotation(1, 0, 0, 0, -1, 0, 0, 0, 1)
+{
+    Init(t.GetGmst(), obs);
+}
+
+// --------------------------------------------------------------------------
+//
+// Get the corresponding rotation angle of the sky coordinate system
+// seen with an Alt/Az telescope.
+//
+Double_t MAstroSky2Local::RotationAngle(Double_t ra, Double_t dec) const
+{
+    TVector3 loc;
+    loc.SetMagThetaPhi(1, TMath::Pi()/2-dec, ra);
+    loc *= *this;
+
+    TRotation rot;
+    rot.RotateZ(-loc.Phi());
+    rot.RotateY(-loc.Theta());
+
+    TVector3 v(1, 0, 0);
+    v *= *this;
+    v *= rot;
+
+    return TMath::ATan2(v(1), v(0));
+}
Index: trunk/MagicSoft/Mars/mastro/MAstroSky2Local.h
===================================================================
--- trunk/MagicSoft/Mars/mastro/MAstroSky2Local.h	(revision 3533)
+++ trunk/MagicSoft/Mars/mastro/MAstroSky2Local.h	(revision 3533)
@@ -0,0 +1,25 @@
+#ifndef MARS_MAstroSky2Local
+#define MARS_MAstroSky2Local
+
+#ifndef ROOT_TRotation
+#include <TRotation.h>
+#endif
+
+class MTime;
+class MObservatory;
+
+class MAstroSky2Local : public TRotation
+{
+private:
+    void Init(Double_t gmst, const MObservatory &obs);
+
+public:
+    MAstroSky2Local(Double_t gmst,  const MObservatory &obs);
+    MAstroSky2Local(const MTime &t, const MObservatory &obs);
+
+    Double_t RotationAngle(Double_t ra, Double_t dec) const;
+
+    ClassDef(MAstroSky2Local, 1) // Rotation Matrix to convert sky coordinates to ideal local coordinates
+};
+
+#endif