The present commit corresponds to an important change in the way the
[u/mrichter/AliRoot.git] / FMD / AliFMD.cxx
index 7e18e88..37a2820 100644 (file)
  * about the suitability of this software for any purpose. It is          *
  * provided "as is" without express or implied warranty.                  *
  **************************************************************************/
-
 /* $Id$ */
-
+/** @file    AliFMD.cxx
+    @author  Christian Holm Christensen <cholm@nbi.dk>
+    @date    Sun Mar 26 17:59:18 2006
+    @brief   Implementation of AliFMD base class 
+*/
 //____________________________________________________________________
 //                                                                          
 // Forward Multiplicity Detector based on Silicon wafers. This class
-// contains the base procedures for the Forward Multiplicity detector
-// Detector consists of 5 Si volumes covered pseudorapidity interval
-// from 1.7 to 5.1.
+// is the driver for especially simulation. 
+//
+// The Forward Multiplicity Detector consists of 3 sub-detectors FMD1,
+// FMD2, and FMD3, each of which has 1 or 2 rings of silicon sensors. 
 //                                                       
 // This is the base class for all FMD manager classes. 
 //                    
 // The actual code is done by various separate classes.   Below is
 // diagram showing the relationship between the various FMD classes
-// that handles the geometry 
+// that handles the simulation
 //
 //
 //       +----------+   +----------+   
-//       | AliFMDv1 |  | AliFMDv1 |   
+//       | AliFMDv1 |  | AliFMDv0 |   
 //       +----------+   +----------+   
-//            |              |
-//       +----+--------------+
-//       |
-//       |           +------------+ 1  +---------------+
-//       |        +- | AliFMDRing |<>--| AliFMDPolygon | 
-//       V     2  |  +------------+    +---------------+   
-//  +--------+<>--+        |
-//  | AliFMD |             ^                       
-//  +--------+<>--+        V 1..2                     
-//            3  | +-------------------+ 
-//               +-| AliFMDSubDetector | 
-//                 +-------------------+
-//                           ^              
-//                           |
-//             +-------------+-------------+
-//             |             |             |         
-//        +---------+   +---------+   +---------+
-//        | AliFMD1 |   | AliFMD2 |   | AliFMD3 |
-//        +---------+   +---------+   +---------+
-//      
+//            |              |                    +-----------------+
+//       +----+--------------+                 +--| AliFMDDigitizer |
+//       |                                     |  +-----------------+
+//       |           +---------------------+   |
+//       |        +--| AliFMDBaseDigitizer |<--+
+//       V     1  |  +---------------------+   |
+//  +--------+<>--+                            |  +------------------+
+//  | AliFMD |                                 +--| AliFMDSDigitizer |    
+//  +--------+<>--+                               +------------------+       
+//            1  |  +---------------------+
+//               +--| AliFMDReconstructor |
+//                  +---------------------+
 //
 // *  AliFMD 
 //    This defines the interface for the various parts of AliROOT that
-//    uses the FMD, like AliFMDDigitizer, AliFMDReconstructor, and so
-//    on. 
+//    uses the FMD, like AliFMDSimulator, AliFMDDigitizer, 
+//    AliFMDReconstructor, and so on. 
+//
+// *  AliFMDv0
+//    This is a concrete implementation of the AliFMD interface. 
+//    It is the responsibility of this class to create the FMD
+//    geometry.
 //
 // *  AliFMDv1 
 //    This is a concrete implementation of the AliFMD interface. 
 //    geometry, process hits in the FMD, and serve hits and digits to
 //    the various clients. 
 //  
-//    It uses the objects of class AliFMDSubDetector to do the various
-//    stuff for FMD1, 2, and 3 
-//
-// *  AliFMDRing 
-//    This class contains all stuff needed to do with a ring.  It's
-//    used by the AliFMDSubDetector objects to instantise inner and
-//    outer rings.  The AliFMDRing objects are shared by the
-//    AliFMDSubDetector objects, and owned by the AliFMDv1 object. 
-//
-// *  AliFMDPolygon 
-//    The code I lifted from TGeoPolygon to help with the geometry of
-//    the modules, as well as to decide wether a hit is actually with
-//    in the real module shape.  The point is, that the shape of the
-//    various ring modules are really polygons (much like the lid of a
-//    coffin), but it's segmented at constant radius.  That is very
-//    hard to implement using GEANT 3.21 shapes, so instead the
-//    modules are implemented as TUBS (tube sections), and in the step
-//    procedure we do the test whether the track was inside the real
-//    shape of the module.  
-//
-// *  AliFMD1, AliFMD2, and AliFMD3 
-//    These are specialisation of AliFMDSubDetector, that contains the
-//    particularities of each of the sub-detector system.  It is
-//    envisioned that the classes should also define the support
-//    volumes and material for each of the detectors.                          
+// *  AliFMDSimulator
+//    This is the base class for the FMD simulation tasks.   The
+//    simulator tasks are responsible to implment the geoemtry, and
+//    process hits. 
 //                                                                          
-// The responsible person for this module is Alla Maevskaia
-// <Alla.Maevskaia@cern.ch>.
+// *  AliFMDReconstructor
+//    This is a concrete implementation of the AliReconstructor that
+//    reconstructs pseudo-inclusive-multiplicities from digits (raw or
+//    from simulation)
 //
-// Many modifications by Christian Holm Christensen <cholm@nbi.dk>
+// Calibration and geometry parameters are managed by separate
+// singleton managers.  These are AliFMDGeometry and
+// AliFMDParameters.  Please refer to these classes for more
+// information on these.
 //
 
 // These files are not in the same directory, so there's no reason to
 // ask the preprocessor to search in the current directory for these
 // files by including them with `#include "..."' 
+#include <TBrowser.h>          // ROOT_TBrowser
 #include <TClonesArray.h>      // ROOT_TClonesArray
-#include <TGeometry.h>         // ROOT_TGeomtry
-#include <TNode.h>             // ROOT_TNode
-#include <TTUBE.h>             // ROOT_TTUBE
+#include <TGeoGlobalMagField.h> // ROOT_TGeoGlobalMagField
+#include <TGeoManager.h>        // ROOT_TGeoManager
+#include <TRotMatrix.h>                // ROOT_TRotMatrix
 #include <TTree.h>             // ROOT_TTree
-#include <TVirtualMC.h>                // ROOT_TVirtualMC
-#include <TBrowser.h>          // ROOT_TBrowser
-#include <TMath.h>             // ROOT_TMath
+#include <TVector2.h>           // ROOT_TVector2 
+#include <TVirtualMC.h>                // ROOT_TVirtualMC
+#include <cmath>                // __CMATH__
 
 #include <AliRunDigitizer.h>   // ALIRUNDIGITIZER_H
 #include <AliLoader.h>         // ALILOADER_H
 #include <AliRun.h>            // ALIRUN_H
 #include <AliMC.h>             // ALIMC_H
-#include <AliLog.h>            // ALILOG_H
 #include <AliMagF.h>           // ALIMAGF_H
+// #include <AliLog.h>         // ALILOG_H
+#include "AliFMDDebug.h" // Better debug macros
 #include "AliFMD.h"            // ALIFMD_H
-#include "AliFMDDigit.h"       // ALIFMDDIGIG_H
+#include "AliFMDDigit.h"       // ALIFMDDIGIT_H
+#include "AliFMDSDigit.h"      // ALIFMDSDIGIT_H
 #include "AliFMDHit.h"         // ALIFMDHIT_H
+#include "AliFMDGeometry.h"    // ALIFMDGEOMETRY_H
+#include "AliFMDDetector.h"    // ALIFMDDETECTOR_H
+#include "AliFMDRing.h"                // ALIFMDRING_H
 #include "AliFMDDigitizer.h"   // ALIFMDDIGITIZER_H
-#include "AliFMD1.h"           // ALIFMD1_H
-#include "AliFMD2.h"           // ALIFMD2_H
-#include "AliFMD3.h"           // ALIFMD3_H
+#include "AliFMDHitDigitizer.h"        // ALIFMDSDIGITIZER_H
+// #define USE_SSDIGITIZER 
+//#ifdef USE_SSDIGITIZER
+//# include "AliFMDSSDigitizer.h"      // ALIFMDSDIGITIZER_H
+//#endif
+// #include "AliFMDGeometryBuilder.h"
 #include "AliFMDRawWriter.h"   // ALIFMDRAWWRITER_H
+#include "AliFMDRawReader.h"   // ALIFMDRAWREADER_H
+#include "AliTrackReference.h" 
+#include "AliFMDStripIndex.h"
+#include "AliFMDParameters.h"
+#include "AliFMDReconstructor.h"
 
 //____________________________________________________________________
 ClassImp(AliFMD)
-
-//____________________________________________________________________
-const Char_t* AliFMD::fgkShortLegName = "FSSL";
-const Char_t* AliFMD::fgkLongLegName  = "FSLL";
+#if 0
+  ; // This is to keep Emacs from indenting the next line 
+#endif 
 
 //____________________________________________________________________
 AliFMD::AliFMD()
-  : fInner(0), 
-    fOuter(0),
-    fFMD1(0),
-    fFMD2(0), 
-    fFMD3(0), 
+  : AliDetector(),
     fSDigits(0), 
     fNsdigits(0),
-    fPrintboardRotationId(0),
-    fIdentityRotationId(0),
-    fShortLegId(0),
-    fLongLegId(0),
-    fLegLength(0),
-    fLegRadius(0),
-    fModuleSpacing(0), 
-    fSiDensity(0),
-    fSiThickness(0),
-    fSiDeDxMip(1.664),
-    fVA1MipRange(0),
-    fAltroChannelSize(0),
-    fSampleRate(0)
+    fDetailed(kTRUE),
+    fUseOld(kFALSE),
+    fUseAssembly(kTRUE),
+    fBad(0) 
 {
   //
   // Default constructor for class AliFMD
   //
-  AliDebug(0, "\tDefault CTOR");
-  fHits     = 0;
-  fDigits   = 0;
-  fIshunt   = 0;
-}
-
-//____________________________________________________________________
-AliFMD::AliFMD(const AliFMD& other)
-  : AliDetector(other),
-    fInner(other.fInner), 
-    fOuter(other.fOuter),
-    fFMD1(other.fFMD1),
-    fFMD2(other.fFMD2), 
-    fFMD3(other.fFMD3), 
-    fSDigits(other.fSDigits), 
-    fNsdigits(other.fNsdigits),
-    fPrintboardRotationId(other.fPrintboardRotationId),
-    fIdentityRotationId(other.fIdentityRotationId),
-    fShortLegId(other.fShortLegId),
-    fLongLegId(other.fLongLegId),
-    fLegLength(other.fLegLength),
-    fLegRadius(other.fLegRadius),
-    fModuleSpacing(other.fModuleSpacing), 
-    fSiDensity(other.fSiDensity),
-    fSiThickness(other.fSiThickness),
-    fSiDeDxMip(other.fSiDeDxMip),
-    fVA1MipRange(other.fVA1MipRange),
-    fAltroChannelSize(other.fAltroChannelSize),
-    fSampleRate(other.fSampleRate)
-{
-  // Copy constructor 
+  AliFMDDebug(10, ("\tDefault CTOR"));
+  fHits        = 0;
+  fDigits      = 0;
+  fIshunt      = 0;
+  fBad         = new TClonesArray("AliFMDHit");
 }
 
 //____________________________________________________________________
-AliFMD::AliFMD(const char *name, const char *title, bool detailed)
+AliFMD::AliFMD(const char *name, const char *title)
   : AliDetector (name, title),
-    fInner(0), 
-    fOuter(0),
-    fFMD1(0),
-    fFMD2(0), 
-    fFMD3(0),
     fSDigits(0),
     fNsdigits(0),
-    fPrintboardRotationId(0),
-    fIdentityRotationId(0),
-    fShortLegId(0),
-    fLongLegId(0),
-    fLegLength(0),
-    fLegRadius(0),
-    fModuleSpacing(0), 
-    fSiDensity(0),
-    fSiThickness(0),
-    fSiDeDxMip(1.664),
-    fVA1MipRange(0),
-    fAltroChannelSize(0),
-    fSampleRate(0)
+    fDetailed(kTRUE),
+    fUseOld(kFALSE),
+    fUseAssembly(kFALSE),
+    fBad(0)
 {
   //
   // Standard constructor for Forward Multiplicity Detector
   //
-  AliDebug(0, "\tStandard CTOR");
-
+  AliFMDDebug(10, ("\tStandard CTOR"));
+  fBad         = new TClonesArray("AliFMDHit");
+  
   // Initialise Hit array
   HitsArray();
   gAlice->GetMCApp()->AddHitList(fHits);
@@ -228,66 +174,8 @@ AliFMD::AliFMD(const char *name, const char *title, bool detailed)
   
   // CHC: What is this?
   fIshunt = 0;
-  SetMarkerColor(kRed);
-  SetLineColor(kYellow);
-  SetSiDensity();
-
-  // Create sub-volume managers 
-  fInner = new AliFMDRing('I', detailed);
-  fOuter = new AliFMDRing('O', detailed);
-  fFMD1  = new AliFMD1();
-  fFMD2  = new AliFMD2();
-  fFMD3  = new AliFMD3();
-
-  // Specify parameters of sub-volume managers 
-  fFMD1->SetInner(fInner);
-  fFMD1->SetOuter(0);
-
-  fFMD2->SetInner(fInner);
-  fFMD2->SetOuter(fOuter);
-  
-  fFMD3->SetInner(fInner);
-  fFMD3->SetOuter(fOuter);
-
-  SetLegLength();
-  SetLegRadius();
-  SetLegOffset();
-  SetModuleSpacing();
-  SetSiThickness();
-  SetSiDensity();
-  SetVA1MipRange();
-  SetAltroChannelSize();
-  SetSampleRate();
-  
-  fInner->SetLowR(4.3);
-  fInner->SetHighR(17.2);
-  fInner->SetWaferRadius(13.4/2);
-  fInner->SetTheta(36/2);
-  fInner->SetNStrips(512);
-  fInner->SetSiThickness(fSiThickness);
-  fInner->SetPrintboardThickness(.11);
-  fInner->SetBondingWidth(.5);
-
-  fOuter->SetLowR(15.6);
-  fOuter->SetHighR(28.0);
-  fOuter->SetWaferRadius(13.4/2);
-  fOuter->SetTheta(18/2);
-  fOuter->SetNStrips(256);
-  fOuter->SetSiThickness(fSiThickness);
-  fOuter->SetPrintboardThickness(.1);
-  fOuter->SetBondingWidth(.5);
-  
-  
-  fFMD1->SetHoneycombThickness(1);
-  fFMD1->SetInnerZ(340.0);
-  
-  fFMD2->SetHoneycombThickness(1);
-  fFMD2->SetInnerZ(83.4);
-  fFMD2->SetOuterZ(75.2);
-
-  fFMD3->SetHoneycombThickness(1);
-  fFMD3->SetInnerZ(-62.8);
-  fFMD3->SetOuterZ(-75.2);
+  //PH  SetMarkerColor(kRed);
+  //PH  SetLineColor(kYellow);
 }
 
 //____________________________________________________________________
@@ -309,36 +197,13 @@ AliFMD::~AliFMD ()
     delete fSDigits;
     fSDigits = 0;
   }
+  if (fBad) {
+    fBad->Delete();
+    delete fBad;
+    fBad = 0;
+  }
 }
 
-//____________________________________________________________________
-AliFMD&
-AliFMD::operator=(const AliFMD& other)
-{
-  AliDetector::operator=(other);
-  fInner               = other.fInner; 
-  fOuter               = other.fOuter;
-  fFMD1                        = other.fFMD1;
-  fFMD2                        = other.fFMD2; 
-  fFMD3                        = other.fFMD3; 
-  fSDigits             = other.fSDigits; 
-  fNsdigits            = other.fNsdigits;
-  fSiDensity           = other.fSiDensity;
-  fPrintboardRotationId        = other.fPrintboardRotationId;
-  fIdentityRotationId  = other.fIdentityRotationId;
-  fShortLegId          = other.fShortLegId;
-  fLongLegId           = other.fLongLegId;
-  fLegLength           = other.fLegLength;
-  fLegRadius           = other.fLegRadius;
-  fModuleSpacing       = other.fModuleSpacing; 
-  fSiDensity           = other.fSiDensity;
-  fSiThickness         = other.fSiThickness;
-  fVA1MipRange         = other.fVA1MipRange;
-  fAltroChannelSize    = other.fAltroChannelSize;
-  fSampleRate          = other.fSampleRate;
-
-  return *this;
-}
 
 //====================================================================
 //
@@ -350,94 +215,58 @@ AliFMD::CreateGeometry()
 {
   //
   // Create the geometry of Forward Multiplicity Detector.  The actual
-  // construction of the geometry is delegated to the class AliFMDRing
-  // and AliFMDSubDetector and the relevant derived classes. 
-  //
-  // The flow of this member function is:
-  //
-  //   FOR rings fInner and fOuter DO  
-  //     AliFMDRing::Init();
-  //   END FOR
-  // 
-  //   Set up hybrud card support (leg) volume shapes  
-  // 
-  //   FOR rings fInner and fOuter DO  
-  //     AliFMDRing::SetupGeometry();
-  //   END FOR
-  // 
-  //   FOR subdetectors fFMD1, fFMD2, and fFMD3 DO 
-  //     AliFMDSubDetector::SetupGeomtry();
-  //   END FOR
-  // 
-  //   FOR subdetectors fFMD1, fFMD2, and fFMD3 DO 
-  //     AliFMDSubDetector::Geomtry();
-  //   END FOR
-  //   
-
-  // DebugGuard guard("AliFMD::CreateGeometry");
-  AliDebug(10, "\tCreating geometry");
-
-  fInner->Init();
-  fOuter->Init();
-
-  Double_t par[3];
-
-  Int_t airId = (*fIdtmed)[kAirId];
-  Int_t alId  = (*fIdtmed)[kAlId];
-  Int_t cId   = (*fIdtmed)[kCarbonId];
-  Int_t siId  = (*fIdtmed)[kSiId];
-  Int_t pcbId = (*fIdtmed)[kPcbId];
-  Int_t plaId = (*fIdtmed)[kPlasticId];
-  Int_t pbId  = fPrintboardRotationId;
-  Int_t idId  = fIdentityRotationId;
-  
-  par[0]      =  fLegRadius - .1;
-  par[1]      =  fLegRadius;
-  par[2]      =  fLegLength / 2;
-  fShortLegId =  gMC->Gsvolu(fgkShortLegName,"TUBE", plaId, par, 3);
-  
-  par[2]      += fModuleSpacing / 2;
-  fLongLegId  =  gMC->Gsvolu(fgkLongLegName,"TUBE", plaId, par, 3);
-
-  fInner->SetupGeometry(airId, siId, pcbId, pbId, idId);
-  fOuter->SetupGeometry(airId, siId, pcbId, pbId, idId);
-
-  fFMD1->SetupGeometry(airId, alId, cId);
-  fFMD2->SetupGeometry(airId, alId, cId);
-  fFMD3->SetupGeometry(airId, alId, cId);
-  
-  fFMD1->Geometry("ALIC", pbId, idId);
-  fFMD2->Geometry("ALIC", pbId, idId);
-  fFMD3->Geometry("ALIC", pbId, idId);    
+  // construction of the geometry is delegated to the class
+  // AliFMDGeometryBuilder, invoked by the singleton manager
+  // AliFMDGeometry. 
+  //
+  AliFMDGeometry*  fmd = AliFMDGeometry::Instance();
+  fmd->SetDetailed(fDetailed);
+  fmd->UseAssembly(fUseAssembly);
+  fmd->Build();
 }    
 
 //____________________________________________________________________
 void AliFMD::CreateMaterials() 
 {
-  // Register various materials and tracking mediums with the
-  // backend.   
-  // 
-  // Currently defined materials and mediums are 
+  // Define the materials and tracking mediums needed by the FMD
+  // simulation.   These mediums are made by sending the messages
+  // AliMaterial, AliMixture, and AliMedium to the passed AliModule
+  // object module.   The defined mediums are 
   // 
-  //    FMD Air                Normal air 
-  //    FMD Si          Active silicon of sensors 
-  //    FMD Carbon      Normal carbon used in support, etc. 
-  //    FMD Kapton      Carbon used in Honeycomb
-  //    FMD PCB         Printed circuit board material 
-  //    FMD Plastic     Material for support legs 
-  // 
-  // Also defined are two rotation matricies. 
-  //
-  // DebugGuard guard("AliFMD::CreateMaterials");
-  AliDebug(10, "\tCreating materials");
+  //   FMD Si$         Silicon (active medium in sensors)
+  //   FMD C$          Carbon fibre (support cone for FMD3 and vacuum pipe)
+  //   FMD Al$         Aluminium (honeycomb support plates)
+  //   FMD PCB$        Printed Circuit Board (FEE board with VA1_3)
+  //   FMD Chip$       Electronics chips (currently not used)
+  //   FMD Air$        Air (Air in the FMD)
+  //   FMD Plastic$    Plastic (Support legs for the hybrid cards)
+  //
+  // The geometry builder should really be the one that creates the
+  // materials, but the architecture of AliROOT makes that design
+  // akward.  What should happen, was that the AliFMDGeometryBuilder
+  // made the mediums, and that this class retrives pointers from the
+  // TGeoManager, and registers the mediums here.  Alas, it's not
+  // really that easy. 
+  //
+  AliFMDDebug(10, ("\tCreating materials"));
+  // Get pointer to geometry singleton object. 
+  AliFMDGeometry* geometry = AliFMDGeometry::Instance();
+  geometry->Init();
+#if 0
+  if (gGeoManager && gGeoManager->GetMedium("FMD Si$")) {
+    // We need to figure out the some stuff about the geometry
+    fmd->ExtractGeomInfo();
+    return;
+  }
+#endif  
   Int_t    id;
   Double_t a                = 0;
   Double_t z                = 0;
   Double_t density          = 0;
   Double_t radiationLength  = 0;
   Double_t absorbtionLength = 999;
-  Int_t    fieldType        = gAlice->Field()->Integ();     // Field type 
-  Double_t maxField         = gAlice->Field()->Max();     // Field max.
+  Int_t    fieldType        = ((AliMagF*)TGeoGlobalMagField::Instance()->GetField())->Integ();     // Field type 
+  Double_t maxField         = ((AliMagF*)TGeoGlobalMagField::Instance()->GetField())->Max();     // Field max.
   Double_t maxBending       = 0;     // Max Angle
   Double_t maxStepSize      = 0.001; // Max step size 
   Double_t maxEnergyLoss    = 1;     // Max Delta E
@@ -447,17 +276,17 @@ void AliFMD::CreateMaterials()
   // Silicon 
   a                = 28.0855;
   z                = 14.;
-  density          = fSiDensity;
+  density          = geometry->GetSiDensity();
   radiationLength  = 9.36;
   maxBending       = 1;
   maxStepSize      = .001;
   precision        = .001;
   minStepSize      = .001;
   id               = kSiId;
-  AliMaterial(id, "FMD Si$", a, z, density, radiationLength, absorbtionLength);
-  AliMedium(kSiId, "FMD Si$",id,1,fieldType,maxField,maxBending,
+  AliMaterial(id, "Si$", a, z, density, radiationLength, absorbtionLength);
+  AliMedium(kSiId, "Si$", id,1,fieldType,maxField,maxBending,
            maxStepSize,maxEnergyLoss,precision,minStepSize);
-
+  
 
   // Carbon 
   a                = 12.011;
@@ -469,10 +298,9 @@ void AliFMD::CreateMaterials()
   precision        = .003;
   minStepSize      = .003;
   id               = kCarbonId;
-  AliMaterial(id, "FMD Carbon$", a, z, density, radiationLength, 
-             absorbtionLength);
-  AliMedium(kCarbonId, "FMD Carbon$",id,0,fieldType,maxField,maxBending,
-           maxStepSize,maxEnergyLoss,precision,minStepSize);
+  AliMaterial(id, "Carbon$", a, z, density, radiationLength, absorbtionLength);
+  AliMedium(kCarbonId, "Carbon$", id,0,fieldType,maxField,maxBending,
+                   maxStepSize,maxEnergyLoss,precision,minStepSize);
 
   // Aluminum
   a                = 26.981539;
@@ -480,32 +308,42 @@ void AliFMD::CreateMaterials()
   density          = 2.7;
   radiationLength  = 8.9;
   id               = kAlId;
-  AliMaterial(id, "FMD Aluminum$", a, z, density, radiationLength, 
-             absorbtionLength);
-  AliMedium(kAlId, "FMD Aluminum$", id, 0, fieldType, maxField, maxBending,
+  AliMaterial(id, "Aluminum$",a,z, density, radiationLength, absorbtionLength);
+  AliMedium(kAlId, "Aluminum$", id, 0, fieldType, maxField, maxBending,
            maxStepSize, maxEnergyLoss, precision, minStepSize);
   
   
+  // Copper 
+  a                = 63.546;
+  z                = 29;
+  density          =  8.96;
+  radiationLength  =  1.43;
+  id               = kCopperId;
+  AliMaterial(id, "Copper$", 
+                     a, z, density, radiationLength, absorbtionLength);
+  AliMedium(kCopperId, "Copper$", id, 0, fieldType, maxField, maxBending,
+           maxStepSize, maxEnergyLoss, precision, minStepSize);
+  
+
   // Silicon chip 
   {
     Float_t as[] = { 12.0107,      14.0067,      15.9994,
-                    1.00794,      28.0855,     107.8682 };
+                     1.00794,     28.0855,     107.8682 };
     Float_t zs[] = {  6.,           7.,           8.,
                      1.,          14.,          47. };
     Float_t ws[] = {  0.039730642,  0.001396798,  0.01169634,
                      0.004367771,  0.844665,     0.09814344903 };
-    density = 2.36436;
+    density          = 2.36436;
     maxBending       = 10;
     maxStepSize      = .01;
     precision        = .003;
     minStepSize      = .003;
-    id = kSiChipId;
-    AliMixture(id, "FMD Si Chip$", as, zs, density, 6, ws);
-    AliMedium(kSiChipId, "FMD Si Chip$", id, 0, fieldType, maxField, 
-             maxBending, maxStepSize, maxEnergyLoss, precision, minStepSize);
+    id               = kSiChipId;
+    AliMixture(id, "Si Chip$", as, zs, density, 6, ws);
+    AliMedium(kSiChipId, "Si Chip$",  id, 0, fieldType, maxField, maxBending, 
+             maxStepSize, maxEnergyLoss, precision, minStepSize);
   }
   
-#if 0
   // Kaption
   {
     Float_t as[] = { 1.00794,  12.0107,  14.010,   15.9994};
@@ -516,12 +354,11 @@ void AliFMD::CreateMaterials()
     maxStepSize      = .001;
     precision        = .001;
     minStepSize      = .001;
-    id               = KaptionId;
-    AliMixture(id, "FMD Kaption$", as, zs, density, 4, ws);
-    AliMedium(kAlId, "FMD Kaption$",id,0,fieldType,maxField,maxBending,
+    id               = kKaptonId;
+    AliMixture(id, "Kaption$", as, zs, density, 4, ws);
+    AliMedium(kKaptonId, "Kaption$", id,0,fieldType,maxField,maxBending,
              maxStepSize,maxEnergyLoss,precision,minStepSize);
   }
-#endif
 
   // Air
   {
@@ -534,8 +371,8 @@ void AliFMD::CreateMaterials()
     precision    = .001;
     minStepSize  = .001;
     id           = kAirId;
-    AliMixture(id, "FMD Air$", as, zs, density, 4, ws);
-    AliMedium(kAirId, "FMD Air$", id,0,fieldType,maxField,maxBending,
+    AliMixture(id, "Air$", as, zs, density, 4, ws);
+    AliMedium(kAirId, "Air$", id,0,fieldType,maxField,maxBending,
              maxStepSize,maxEnergyLoss,precision,minStepSize);
   }
   
@@ -559,11 +396,22 @@ void AliFMD::CreateMaterials()
     precision    = .001;
     minStepSize  = .001;
     id           = kPcbId;
-    AliMixture(id, "FMD PCB$", as, zs, density, 14, ws);
-    AliMedium(kPcbId, "FMD PCB$", id,0,fieldType,maxField,maxBending,
+    AliMixture(id, "PCB$", as, zs, density, 14, ws);
+    AliMedium(kPcbId, "PCB$", id,0,fieldType,maxField,maxBending,
              maxStepSize,maxEnergyLoss,precision,minStepSize);
   }
   
+  // Stainless steel
+  {
+    Float_t as[] = { 55.847, 51.9961, 58.6934, 28.0855 };
+    Float_t zs[] = { 26.,    24.,     28.,     14.     };
+    Float_t ws[] = { .715,   .18,     .1,      .005    };
+    density      = 7.88;
+    id           = kSteelId;
+    AliMixture(id, "Steel$", as, zs, density, 4, ws);
+    AliMedium(kSteelId, "Steel$", id, 0, fieldType, maxField, maxBending, 
+             maxStepSize, maxEnergyLoss, precision, minStepSize);
+  }
   // Plastic 
   {
     Float_t as[] = { 1.01, 12.01 };
@@ -575,106 +423,56 @@ void AliFMD::CreateMaterials()
     precision    = .003;
     minStepSize  = .003;
     id           = kPlasticId;
-    AliMixture(id, "FMD Plastic$", as, zs, density, -2, ws);
-    AliMedium(kPlasticId, "FMD Plastic$", id,0,fieldType,maxField,maxBending,
-               maxStepSize,maxEnergyLoss,precision,minStepSize);
+    AliMixture(id, "Plastic$", as, zs, density, -2, ws);
+    AliMedium(kPlasticId, "Plastic$", id,0,fieldType,maxField,maxBending,
+             maxStepSize,maxEnergyLoss,precision,minStepSize);
   }
-  AliMatrix(fPrintboardRotationId, 90, 90, 0, 90, 90, 0);
-  AliMatrix(fIdentityRotationId, 90, 0, 90, 90, 0, 0);
+
 }
 
 //____________________________________________________________________
 void  
 AliFMD::Init()
 {
-  //
-  // Initialis the FMD after it has been built
-  Int_t i;
-  //
-  if (fDebug) {
-    cout << "\n" << ClassName() << ": " << flush;
-    for (i = 0; i < 35; i++) cout << "*";
-    cout << " FMD_INIT ";
-    for (i = 0; i < 35; i++) cout << "*";
-    cout << "\n" << ClassName() << ": " << flush;
-    //
-    // Here the FMD initialisation code (if any!)
-    for (i = 0; i < 80; i++) cout << "*";
-    cout << endl;
+  // Initialize the detector 
+  // 
+  AliFMDDebug(1, ("Initialising FMD detector object"));
+  TVirtualMC*      mc     = TVirtualMC::GetMC();
+  AliFMDGeometry*  fmd    = AliFMDGeometry::Instance();
+  const TArrayI&   actGeo = fmd->ActiveIds();
+  TArrayI          actVmc(actGeo.fN);
+  for (Int_t i = 0; i < actGeo.fN; i++) {
+    TGeoVolume *sens = gGeoManager->GetVolume(actGeo[i]);
+    if (!sens) {
+      AliError(Form("No TGeo volume for sensitive volume ID=%d",actGeo[i]));
+      continue;
+    }   
+    actVmc[i] = mc->VolId(sens->GetName());
+    AliFMDDebug(1, ("Active vol id # %d: %d changed to %d", 
+                   i, actGeo[i], actVmc[i]));
   }
-  //
-  //
+  fmd->SetActive(actVmc.fArray, actVmc.fN);
+  // fmd->InitTransformations();
 }
 
-//====================================================================
-//
-// Graphics and event display
-//
 //____________________________________________________________________
-void 
-AliFMD::BuildGeometry()
+void
+AliFMD::FinishEvent()
 {
-  //
-  // Build simple ROOT TNode geometry for event display
-  //
-  // Build a simplified geometry of the FMD used for event display  
+  // Called at the end of the an event in simulations.  If the debug
+  // level is high enough, then the `bad' hits are printed.
   // 
-  // The actual building of the TNodes is done by
-  // AliFMDSubDetector::SimpleGeometry. 
-  AliDebug(10, "\tCreating a simplified geometry");
-
-  TNode* top = gAlice->GetGeometry()->GetNode("alice");
-  
-  fFMD1->SimpleGeometry(fNodes, top, GetLineColor(), 0);
-  fFMD2->SimpleGeometry(fNodes, top, GetLineColor(), 0);
-  fFMD3->SimpleGeometry(fNodes, top, GetLineColor(), 0);
+  if (AliLog::GetDebugLevel("FMD", "AliFMD") < 10) return;
+  if (fBad && fBad->GetEntries() > 0) {
+    AliWarning((Form("EndEvent", "got %d 'bad' hits", fBad->GetEntries())));
+    TIter next(fBad);
+    AliFMDHit* hit;
+    while ((hit = static_cast<AliFMDHit*>(next()))) hit->Print("D");
+    fBad->Clear();
+  }
 }
 
-//____________________________________________________________________
-void 
-AliFMD::DrawDetector()
-{
-  //
-  // Draw a shaded view of the Forward multiplicity detector
-  //
-  // DebugGuard guard("AliFMD::DrawDetector");
-  AliDebug(10, "\tDraw detector");
-  
-  //Set ALIC mother transparent
-  gMC->Gsatt("ALIC","SEEN",0);
-  gMC->Gsatt(fgkShortLegName,"SEEN",1);
-  gMC->Gsatt(fgkLongLegName,"SEEN",1);
-
-  //Set volumes visible
-  fFMD1->Gsatt();
-  fFMD2->Gsatt();
-  fFMD3->Gsatt();
-  fInner->Gsatt();
-  fOuter->Gsatt();
 
-  //
-  gMC->Gdopt("hide", "on");
-  gMC->Gdopt("shad", "on");
-  gMC->Gsatt("*", "fill", 7);
-  gMC->SetClipBox(".");
-  gMC->SetClipBox("*", 0, 1000, -1000, 1000, -1000, 1000);
-  gMC->DefaultRange();
-  gMC->Gdraw("alic", 40, 30, 0, 12, 12, .055, .055);
-  gMC->Gdhead(1111, "Forward Multiplicity Detector");
-  gMC->Gdman(16, 10, "MAN");
-  gMC->Gdopt("hide", "off");
-}
-
-//____________________________________________________________________
-Int_t 
-AliFMD::DistanceToPrimitive(Int_t, Int_t)
-{
-  //
-  // Calculate the distance from the mouse to the FMD on the screen
-  // Dummy routine
-  //
-  return 9999;
-}
 
 //====================================================================
 //
@@ -735,8 +533,6 @@ AliFMD::SetTreeAddress()
   }
 }
 
-
-
 //____________________________________________________________________
 void 
 AliFMD::SetHitsAddressBranch(TBranch *b)
@@ -744,6 +540,13 @@ AliFMD::SetHitsAddressBranch(TBranch *b)
   // Set the TClonesArray to read hits into. 
   b->SetAddress(&fHits);
 }
+//____________________________________________________________________
+void 
+AliFMD::SetSDigitsAddressBranch(TBranch *b)
+{
+  // Set the TClonesArray to read hits into. 
+  b->SetAddress(&fSDigits);
+}
 
 //____________________________________________________________________
 void 
@@ -770,40 +573,41 @@ AliFMD::AddHit(Int_t track, Int_t *vol, Float_t *hits)
   //    hits[9]         [Float_t  ] Time when the track hit
   // 
   // 
-  AddHit(track, 
-        UShort_t(vol[0]),  // Detector # 
-        Char_t(vol[1]),    // Ring ID
-        UShort_t(vol[2]),  // Sector # 
-        UShort_t(vol[3]),  // Strip # 
-        hits[0],           // X
-        hits[1],           // Y
-        hits[2],           // Z
-        hits[3],           // Px
-        hits[4],           // Py
-        hits[5],           // Pz
-        hits[6],           // Energy loss 
-        Int_t(hits[7]),    // PDG 
-        hits[8]);          // Time
+  AddHitByFields(track, 
+                UShort_t(vol[0]),  // Detector # 
+                Char_t(vol[1]),    // Ring ID
+                UShort_t(vol[2]),  // Sector # 
+                UShort_t(vol[3]),  // Strip # 
+                hits[0],           // X
+                hits[1],           // Y
+                hits[2],           // Z
+                hits[3],           // Px
+                hits[4],           // Py
+                hits[5],           // Pz
+                hits[6],           // Energy loss 
+                Int_t(hits[7]),    // PDG 
+                hits[8]);          // Time
 }
 
 //____________________________________________________________________
-void 
-AliFMD::AddHit(Int_t    track, 
-              UShort_t detector, 
-              Char_t   ring, 
-              UShort_t sector, 
-              UShort_t strip, 
-              Float_t  x, 
-              Float_t  y, 
-              Float_t  z,
-              Float_t  px, 
-              Float_t  py, 
-              Float_t  pz,
-              Float_t  edep,
-              Int_t    pdg,
-              Float_t  t)
+AliFMDHit*
+AliFMD::AddHitByFields(Int_t    track, 
+                      UShort_t detector, 
+                      Char_t   ring, 
+                      UShort_t sector, 
+                      UShort_t strip, 
+                      Float_t  x, 
+                      Float_t  y, 
+                      Float_t  z,
+                      Float_t  px, 
+                      Float_t  py, 
+                      Float_t  pz,
+                      Float_t  edep,
+                      Int_t    pdg,
+                      Float_t  t, 
+                      Float_t  l, 
+                      Bool_t   stop)
 {
-  //
   // Add a hit to the list
   //
   // Parameters:
@@ -822,6 +626,8 @@ AliFMD::AddHit(Int_t    track,
   //    edep     Energy deposited by track
   //    pdg      Track's particle Id #
   //    t        Time when the track hit 
+  //    l         Track length through the material. 
+  //    stop      Whether track was stopped or disappeared
   // 
   TClonesArray& a = *(HitsArray());
   // Search through the list of already registered hits, and see if we
@@ -829,31 +635,46 @@ AliFMD::AddHit(Int_t    track,
   // a new hit, but rather update the energy deposited in the hit.
   // This is done, so that a FLUKA based simulation will get the
   // number of hits right, not just the enerrgy deposition. 
+  AliFMDHit* hit = 0;
   for (Int_t i = 0; i < fNhits; i++) {
     if (!a.At(i)) continue;
-    AliFMDHit* hit = static_cast<AliFMDHit*>(a.At(i));
+    hit = static_cast<AliFMDHit*>(a.At(i));
     if (hit->Detector() == detector 
        && hit->Ring() == ring
        && hit->Sector() == sector 
        && hit->Strip() == strip
        && hit->Track() == track) {
-      Warning("AddHit", "already had a hit in FMD%d%c[%2d,%3d] for track # %d,"
-             " adding energy (%f) to that hit (%f) -> %f", 
-             detector, ring, sector, strip, track, edep, hit->Edep(),
-             hit->Edep() + edep);
+      AliFMDDebug(1, ("already had a hit in FMD%d%c[%2d,%3d] for track # %d,"
+                      " adding energy (%f) to that hit (%f) -> %f", 
+                      detector, ring, sector, strip, track, edep, hit->Edep(),
+                      hit->Edep() + edep));
       hit->SetEdep(hit->Edep() + edep);
-      return;
+      return hit;
     }
   }
   // If hit wasn't already registered, do so know. 
-  new (a[fNhits]) AliFMDHit(fIshunt, track, detector, ring, sector, strip, 
-                           x, y, z, px, py, pz, edep, pdg, t);
+  hit = new (a[fNhits]) AliFMDHit(fIshunt, track, detector, ring, sector, 
+                                 strip, x, y, z, px, py, pz, edep, pdg, t, 
+                                 l, stop);
+  // gMC->AddTrackReference(track, 12);
   fNhits++;
+  
+  //Reference track
+
+  AliMC *mcApplication = (AliMC*)gAlice->GetMCApp();
+  
+  AliTrackReference* trackRef = AddTrackReference(mcApplication->GetCurrentTrackNumber(), AliTrackReference::kFMD); 
+  UInt_t stripId = AliFMDStripIndex::Pack(detector,ring,sector,strip);
+  trackRef->SetUserId(stripId);
+  
+  
+  
+  return hit;
 }
 
 //____________________________________________________________________
 void 
-AliFMD::AddDigit(Int_t* digits)
+AliFMD::AddDigit(Int_t* digits, Int_t*)
 {
   // Add a digit to the Digit tree 
   // 
@@ -867,24 +688,27 @@ AliFMD::AddDigit(Int_t* digits)
   //    digits[5]  [Short_t]  ADC Count, -1 if not used
   //    digits[6]  [Short_t]  ADC Count, -1 if not used 
   // 
-  AddDigit(UShort_t(digits[0]),  // Detector #
-          Char_t(digits[1]),    // Ring ID
-          UShort_t(digits[2]),  // Sector #
-          UShort_t(digits[3]),  // Strip #
-          UShort_t(digits[4]),  // ADC Count1 
-          Short_t(digits[5]),   // ADC Count2 
-          Short_t(digits[6]));  // ADC Count3 
+  AddDigitByFields(UShort_t(digits[0]),  // Detector #
+                  Char_t(digits[1]),    // Ring ID
+                  UShort_t(digits[2]),  // Sector #
+                  UShort_t(digits[3]),  // Strip #
+                  UShort_t(digits[4]),  // ADC Count1 
+                  Short_t(digits[5]),   // ADC Count2 
+                  Short_t(digits[6]),   // ADC Count3 
+                  Short_t(digits[7])); 
 }
 
 //____________________________________________________________________
 void 
-AliFMD::AddDigit(UShort_t detector, 
-                Char_t   ring, 
-                UShort_t sector, 
-                UShort_t strip, 
-                UShort_t count1, 
-                Short_t  count2,
-                Short_t  count3)
+AliFMD::AddDigitByFields(UShort_t       detector, 
+                        Char_t         ring, 
+                        UShort_t       sector, 
+                        UShort_t       strip, 
+                        UShort_t       count1, 
+                        Short_t        count2,
+                        Short_t        count3, 
+                        Short_t        count4,
+                        const TArrayI& refs)
 {
   // add a real digit - as coming from data
   // 
@@ -900,7 +724,14 @@ AliFMD::AddDigit(UShort_t detector,
   TClonesArray& a = *(DigitsArray());
   
   new (a[fNdigits++]) 
-    AliFMDDigit(detector, ring, sector, strip, count1, count2, count3);
+    AliFMDDigit(detector, ring, sector, strip, 
+               count1, count2, count3, count4, refs);
+  AliFMDDebug(15, ("Adding digit # %5d/%5d for FMD%d%c[%2d,%3d]"
+                  "=(%d,%d,%d,%d) with %d tracks",
+                  fNdigits-1, a.GetEntriesFast(),
+                  detector, ring, sector, strip, 
+                  count1, count2, count3, count4, refs.fN));
+  
 }
 
 //____________________________________________________________________
@@ -920,26 +751,33 @@ AliFMD::AddSDigit(Int_t* digits)
   //    digits[6]  [Short_t]  ADC Count, -1 if not used
   //    digits[7]  [Short_t]  ADC Count, -1 if not used 
   // 
-  AddSDigit(UShort_t(digits[0]),  // Detector #
-           Char_t(digits[1]),    // Ring ID
-           UShort_t(digits[2]),  // Sector #
-           UShort_t(digits[3]),  // Strip #
-           Float_t(digits[4]),   // Edep
-           UShort_t(digits[5]),  // ADC Count1 
-           Short_t(digits[6]),   // ADC Count2 
-           Short_t(digits[7]));  // ADC Count3 
+  AddSDigitByFields(UShort_t(digits[0]),   // Detector #
+                   Char_t(digits[1]),     // Ring ID
+                   UShort_t(digits[2]),   // Sector #
+                   UShort_t(digits[3]),   // Strip #
+                   Float_t(digits[4]),    // Edep
+                   UShort_t(digits[5]),   // ADC Count1 
+                   Short_t(digits[6]),    // ADC Count2 
+                   Short_t(digits[7]),    // ADC Count3 
+                   Short_t(digits[8]),    // ADC Count4
+                   UShort_t(digits[9]),   // N particles
+                   UShort_t(digits[10])); // N primaries
 }
 
 //____________________________________________________________________
 void 
-AliFMD::AddSDigit(UShort_t detector, 
-                 Char_t   ring, 
-                 UShort_t sector, 
-                 UShort_t strip, 
-                 Float_t  edep,
-                 UShort_t count1, 
-                 Short_t  count2,
-                 Short_t  count3)
+AliFMD::AddSDigitByFields(UShort_t       detector, 
+                         Char_t         ring, 
+                         UShort_t       sector, 
+                         UShort_t       strip, 
+                         Float_t        edep,
+                         UShort_t       count1, 
+                         Short_t        count2,
+                         Short_t        count3, 
+                         Short_t        count4, 
+                         UShort_t       ntot, 
+                         UShort_t       nprim,
+                         const TArrayI& refs)
 {
   // add a summable digit
   // 
@@ -955,17 +793,18 @@ AliFMD::AddSDigit(UShort_t detector,
   //    count3    ADC count (a 10-bit word), or -1 if not used
   //
   TClonesArray& a = *(SDigitsArray());
+  // AliFMDDebug(0, ("Adding sdigit # %d", fNsdigits));
   
   new (a[fNsdigits++]) 
-    AliFMDSDigit(detector, ring, sector, strip, edep, count1, count2, count3);
+    AliFMDSDigit(detector, ring, sector, strip, edep, 
+                count1, count2, count3, count4, ntot, nprim, refs);
 }
 
 //____________________________________________________________________
 void 
 AliFMD::ResetSDigits()
 {
-  //
-  // Reset number of digits and the digits array for this detector
+  // Reset number of digits and the digits array for this detector. 
   //
   fNsdigits   = 0;
   if (fSDigits) fSDigits->Clear();
@@ -1019,12 +858,9 @@ AliFMD::Hits2Digits()
   // Create AliFMDDigit's from AliFMDHit's.  This is done by making a
   // AliFMDDigitizer, and executing that code.
   // 
-  AliRunDigitizer* manager = new AliRunDigitizer(1, 1);
-  manager->SetInputStream(0, "galice.root");
-  manager->SetOutputFile("H2Dfile");
-  
-  /* AliDigitizer* dig =*/ CreateDigitizer(manager);
-  manager->Exec("");
+  AliFMDHitDigitizer digitizer(this, AliFMDHitDigitizer::kDigits);
+  digitizer.Init();
+  digitizer.Exec("");
 }
 
 //____________________________________________________________________
@@ -1034,11 +870,9 @@ AliFMD::Hits2SDigits()
   // Create AliFMDSDigit's from AliFMDHit's.  This is done by creating
   // an AliFMDSDigitizer object, and executing it. 
   // 
-  AliFMDSDigitizer* digitizer = new AliFMDSDigitizer("galice.root");
-  digitizer->SetSampleRate(fSampleRate);
-  digitizer->SetVA1MipRange(fVA1MipRange);
-  digitizer->SetAltroChannelSize(fAltroChannelSize);
-  digitizer->Exec("");
+  AliFMDHitDigitizer digitizer(this, AliFMDHitDigitizer::kSDigits);
+  digitizer.Init();
+  digitizer.Exec("");
 }
 
   
@@ -1047,10 +881,20 @@ AliDigitizer*
 AliFMD::CreateDigitizer(AliRunDigitizer* manager) const
 {
   // Create a digitizer object 
-  AliFMDDigitizer* digitizer = new AliFMDDigitizer(manager);
-  digitizer->SetSampleRate(fSampleRate);
-  digitizer->SetVA1MipRange(fVA1MipRange);
-  digitizer->SetAltroChannelSize(fAltroChannelSize);
+  
+  /* This is what we probably _should_ do */
+  AliFMDBaseDigitizer* digitizer = 0;
+  
+#ifdef USE_SSDIGITIZER
+  digitizer = new AliFMDSSDigitizer(manager);
+#else 
+  /* This is what we actually do, and will work */
+#if 0
+  AliInfo("SDigit->Digit conversion not really supported, "
+         "doing Hit->Digit conversion instead");
+#endif
+  digitizer = new AliFMDDigitizer(manager);
+#endif
   return digitizer;
 }
 
@@ -1067,66 +911,48 @@ AliFMD::Digits2Raw()
   // This uses the class AliFMDRawWriter to do the job.   Please refer
   // to that class for more information. 
   AliFMDRawWriter writer(this);
-  writer.SetSampleRate(fSampleRate);
   writer.Exec();
 }
 
-//==================================================================
+//====================================================================
 //
-// Various setter functions for the common paramters 
+// Raw data reading 
 //
-
 //__________________________________________________________________
-void 
-AliFMD::SetLegLength(Double_t length) 
+Bool_t
+AliFMD::Raw2SDigits(AliRawReader* reader) 
 {
-  // Set lenght of plastic legs that hold the hybrid (print board and
-  // silicon sensor) onto the honeycomp support
-  //
-  AliDebug(10, Form("\tLeg length set to %lf cm", length));
-  fLegLength = length;
-  fInner->SetLegLength(fLegLength);
-  fOuter->SetLegLength(fLegLength);
-}
+  // Turn digits into raw data. 
+  // 
+  // This uses the class AliFMDRawWriter to do the job.   Please refer
+  // to that class for more information. 
+  AliFMDParameters::Instance()->Init();
+  MakeTree("S");
+  MakeBranch("S");
+  
+  TClonesArray*       sdigits = SDigits();
+  AliFMDReconstructor rec;
+  
+  // The two boolean arguments
+  //   Make sdigits instead of digits 
+  //   Subtract the pedestal off the signal
+  rec.Digitize(reader, sdigits);
+  // 
+  // Bool_t ret = fmdReader.ReadAdcs(sdigits, kTRUE, kTRUE);
+  // sdigits->ls();
+  UShort_t ns = sdigits->GetEntriesFast();
+  for (UShort_t i = 0; i < ns; i++) 
+    sdigits->At(i)->Print("pl");
+  
+  AliFMDDebug(1, ("Got a total of %d SDigits", ns));
 
-//__________________________________________________________________
-void 
-AliFMD::SetLegOffset(Double_t offset) 
-{
-  // Set offset from edge of hybrid to plastic legs that hold the
-  // hybrid (print board and silicon sensor) onto the honeycomp
-  // support 
-  //
-  AliDebug(10, Form("\tLeg offset set to %lf cm", offset));
-  fInner->SetLegOffset(offset);
-  fOuter->SetLegOffset(offset);
-}
+  fLoader->TreeS()->Fill();
+  ResetSDigits();
+  fLoader->WriteSDigits("OVERWRITE");
 
-//__________________________________________________________________
-void 
-AliFMD::SetLegRadius(Double_t radius) 
-{
-  // Set the diameter of the plastic legs that hold the hybrid (print
-  // board and silicon sensor) onto the honeycomp support
-  //
-  AliDebug(10, Form("\tLeg radius set to %lf cm", radius));
-  fLegRadius = radius;
-  fInner->SetLegRadius(fLegRadius);
-  fOuter->SetLegRadius(fLegRadius);
+  return kTRUE;
 }
 
-//__________________________________________________________________
-void 
-AliFMD::SetModuleSpacing(Double_t spacing) 
-{
-  // Set the distance between the front and back sensor modules
-  // (module staggering). 
-  //
-  AliDebug(10, Form("\tModule spacing set to %lf cm", spacing));  
-  fModuleSpacing = spacing;
-  fInner->SetModuleSpacing(fModuleSpacing);
-  fOuter->SetModuleSpacing(fModuleSpacing);
-}
 
 //====================================================================
 //
@@ -1138,16 +964,58 @@ AliFMD::Browse(TBrowser* b)
 {
   // Browse this object. 
   //
-  AliDebug(30, "\tBrowsing the FMD");
+  AliFMDDebug(30, ("\tBrowsing the FMD"));
   AliDetector::Browse(b);
-  if (fInner) b->Add(fInner, "Inner Ring");
-  if (fOuter) b->Add(fOuter, "Outer Ring");
-  if (fFMD1)  b->Add(fFMD1,  "FMD1 SubDetector");
-  if (fFMD2)  b->Add(fFMD2,  "FMD2 SubDetector");
-  if (fFMD3)  b->Add(fFMD3,  "FMD3 SubDetector");
+  b->Add(AliFMDGeometry::Instance());
 }
 
-
+//____________________________________________________________________ 
+void
+AliFMD::AddAlignableVolumes() const
+{
+  //
+  // Create entries for alignable volumes associating the symbolic volume
+  // name with the corresponding volume path. Needs to be syncronized with
+  // eventual changes in the geometry.
+  // 
+  // This code was made by Raffaele Grosso <rgrosso@mail.cern.ch>.  I
+  // (cholm) will probably want to change it.   For one, I think it
+  // should be the job of the geometry manager to deal with this. 
+  AliInfo("Add FMD alignable volumes");
+  AliFMDGeometry::Instance()->SetAlignableVolumes();
+#if 0  
+  for(size_t f = 1; f <= 3; f++){ // Detector 1,2,3
+    for(size_t tb =  0; tb <2 ; tb++){ // Top/Bottom 
+      char     stb = tb == 0 ? 'T' : 'B';
+      unsigned min = tb == 0 ? 0   : 5;
+
+      TString halfVol(Form("/ALIC_1/F%dM%c_%d", f, stb, f));
+      TString halfSym(halfVol);
+      if(!gGeoManager->SetAlignableEntry(halfSym.Data(),halfVol.Data()))
+       AliFatal(Form("Alignable entry %s not created. "
+                     "Volume path %s not valid", 
+                     halfSym.Data(),halfVol.Data()));
+      for(size_t io = 0; io < 2; io++){ // inner, outer 
+       if (f==1 && io==1) continue; // Only one ring in FMD1 
+       if(tb == 1 && io==1) min=10;
+       char     sio = (io == 0 ? 'I' : 'O');
+       unsigned nio = (io == 0 ? 3   : 9);
+       unsigned max = (io == 0 ? 5   : 10) + min;
+       
+       for(size_t i = min; i < max; i++) { // Modules
+         TString modVol(Form("%s/F%c%cV_7%d/F%cSE_%d", halfVol.Data(), 
+                             sio, stb, nio, sio, i));
+         TString modSym(modVol);
+         if(!gGeoManager->SetAlignableEntry(modSym.Data(),modVol.Data()))
+           AliFatal(Form("Alignable entry %s not created. "
+                         "Volume path %s not valid", 
+                         modSym.Data(), modVol.Data()));
+       }
+      }
+    }
+  }
+#endif
+}
 //___________________________________________________________________
 //
 // EOF