Modified THcDriftChamberPlane.cxx and THcDriftChamberPlane.h

Main purpose was to have option for per wire tzero offsets

Modified THcDriftChamberPlane.h
------------------------------
1) added fUsingTzeroPerWire as parameter flag to switch on per wire tzero offsets when parameter equals 1
2) fTzeroWire is array of tzero offsets for each wire in plane

Modified THcDriftChamberPlane.cxx
------------------------------
1) THcDriftChamberPlane::ReadDatabase
    a)set a default value of fUsingTzeroPerWire=0
    b)added to DBRequest list option to read in fUsingTzeroPerWire
    c) if fUsingTzeroPerWire=1 then separate DBRequest to read in fTzeroWire
   d) if fUsingTzeroPerWire=0 then all fTzeroWire=0

2) THcDriftChamberPlane::ProcessHits
------------------------------------
   a) Modify calcualation of drift time to subtract fTzeroWire
Double_t time = -StartTime- rawtdc*fNSperChan + fPlaneTimeZero - fTzeroWire[wireNum-1];

src/THcDriftChamberPlane.cxx

@@ -92,13 +92,14 @@ Int_t THcDriftChamberPlane::ReadDatabase( const TDatime& date )
   UInt_t NumDriftMapBins;
   Double_t DriftMapFirstBin;
   Double_t DriftMapBinSize;
-
+  fUsingTzeroPerWire=0;
   prefix[0]=tolower(GetParent()->GetPrefix()[0]);
   prefix[1]='\0';
   DBRequest list[]={
     {"driftbins", &NumDriftMapBins, kInt},
     {"drift1stbin", &DriftMapFirstBin, kDouble},
     {"driftbinsz", &DriftMapBinSize, kDouble},
+    {"_using_tzero_per_wire", &fUsingTzeroPerWire, kInt,0,1},
     {0}
   };
   gHcParms->LoadParmValues((DBRequest*)&list,prefix);
@@ -110,6 +111,7 @@ Int_t THcDriftChamberPlane::ReadDatabase( const TDatime& date )
   };
   gHcParms->LoadParmValues((DBRequest*)&list2,prefix);
 
+
   // Retrieve parameters we need from parent class
   THcDC* fParent;
 
@@ -130,6 +132,25 @@ Int_t THcDriftChamberPlane::ReadDatabase( const TDatime& date )
 
   fNSperChan = fParent->GetNSperChan();
 
+  if (fUsingTzeroPerWire==1) {
+  fTzeroWire = new Double_t [fNWires];
+  DBRequest list3[]={
+    {Form("tzero%s",GetName()),fTzeroWire,kDouble,fNWires},
+    {0}
+  };
+  gHcParms->LoadParmValues((DBRequest*)&list3,prefix);
+  printf(" using tzero per wire plane = %s  nwires = %d  \n",GetName(),fNWires);
+      for (Int_t iw=0;iw < fNWires;iw++) {
+	printf("%d  %f ",iw+1,fTzeroWire[iw]) ;
+ 	if ( iw!=0 && iw%8 == 0) printf("\n") ;
+	}
+  } else {
+  fTzeroWire = new Double_t [fNWires];
+  for (Int_t iw=0;iw < fNWires;iw++) {
+    fTzeroWire[iw]=0.0;
+    } 
+  }
+
   // Calculate Geometry Constants
   // Do we want to move all this to the Chamber of DC Package leve
   // as that is where these things will be needed?
@@ -322,7 +343,8 @@ Int_t THcDriftChamberPlane::ProcessHits(TClonesArray* rawhits, Int_t nexthit)
 	// Increment late count
       } else {
 	Double_t time = -StartTime   // (comes from h_trans_scin
-	  - rawtdc*fNSperChan + fPlaneTimeZero; // fNSperChan > 0 for 1877
+	  - rawtdc*fNSperChan + fPlaneTimeZero - fTzeroWire[wireNum-1]; // fNSperChan > 0 for 1877
+	// (cout << " Plane = " << GetName() << " wire = " << wireNum << " " <<  fPlaneTimeZero << " "  << fTzeroWire[wireNum-1] << endl;
 	// < 0 for Caen1190.
 	//	  - (rawtdc-reftime)*fNSperChan + fPlaneTimeZero;
 	// How do we get this start time from the hodoscope to here

src/THcDriftChamberPlane.h

@@ -79,6 +79,7 @@ protected:
   Int_t fPlaneNum;
   Int_t fPlaneIndex;		/* Index of this plane within it's chamber */
   Int_t fChamberNum;
+  Int_t fUsingTzeroPerWire;
   Int_t fNRawhits;
   Int_t fNWires;
   Int_t fWireOrder;
@@ -104,6 +105,8 @@ protected:
 
   Double_t fNSperChan;		/* TDC bin size */
 
+  Double_t* fTzeroWire;
+
   virtual Int_t  ReadDatabase( const TDatime& date );
   virtual Int_t  DefineVariables( EMode mode = kDefine );