[u/mrichter/AliRoot.git] / ITS / AliITSsegmentationSPD.cxx

/**************************************************************************
 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
 *                                                                        *
 * Author: The ALICE Off-line Project.                                    *
 * Contributors are mentioned in the code where appropriate.              *
 *                                                                        *
 * Permission to use, copy, modify and distribute this software and its   *
 * documentation strictly for non-commercial purposes is hereby granted   *
 * without fee, provided that the above copyright notice appears in all   *
 * copies and that both the copyright notice and this permission notice   *
 * appear in the supporting documentation. The authors make no claims     *
 * about the suitability of this software for any purpose. It is          *
 * provided "as is" without express or implied warranty.                  *
 **************************************************************************/

#include <TMath.h>
#include <TF1.h>

#include "AliITSsegmentationSPD.h"
#include "AliITSgeom.h"

ClassImp(AliITSsegmentationSPD)


Float_t ColFromZ300(Float_t z) {
// Get column number for each z-coordinate taking into account the 
// extra pixels in z direction assuming 300 micron sized pixels.
     Float_t col = 0.0;
     Float_t pitchz = 300.0;
     col = Float_t (z/pitchz);
     return col;
}
//_____________________________________________________________________________
Float_t ZFromCol300(Int_t col) {
// same comments as above
// Get z-coordinate for each colunm number
  Float_t pitchz = 300.0;
  Float_t z = 0.0;
  z = (col+0.5)*pitchz;
  return z;
}
//_____________________________________________________________________________
Float_t ZpitchFromCol300(Int_t col) {
  // returns Z pixel pitch for 300 micron pixels.
  return 300.0;
}
//_____________________________________________________________________________
Float_t ColFromZ(Float_t z) {
// hard-wired - keep it like this till we can parametrise 
// and get rid of AliITSgeomSPD425
// Get column number for each z-coordinate taking into account the 
// extra pixels in z direction 

  Float_t col = 0;
  Float_t pitchz = 425;
  if( z < 13175) {
    col = Float_t(z/pitchz);
  } else if( z < 14425) {  
    pitchz = 625;
    col = 31 + (z - 13175)/pitchz;
  } else if( z < 27175) {  
    col = 33 + (z - 14425)/pitchz;
  } else if( z < 28425) {  
    pitchz = 625;
    col = 63 + (z - 27175)/pitchz;
  } else if( z < 41175) {  
    col = 65 + (z - 28425)/pitchz;
  } else if( z < 42425) {  
    pitchz = 625;
    col = 95 + (z - 41175)/pitchz;
  } else if( z < 55175) {  
    col = 97 + (z - 42425)/pitchz;
  } else if( z < 56425) {  
    pitchz = 625;
    col = 127 + (z - 55175)/pitchz;
  } else if( z < 69175) {  
    col = 129 + (z - 56425)/pitchz;
  } else if( z < 70425) {  
    pitchz = 625;
    col = 159 + (z - 69175)/pitchz;
  } else if( z < 83600) {  
    col = 161 + (z - 70425)/pitchz;
  }   
  return TMath::Abs(col);
}

//_____________________________________________________________________________
Float_t ZFromCol(Int_t col) {
// same comments as above
// Get z-coordinate for each colunm number

  Float_t pitchz = 425;
  Float_t z = 0;
  if( col >=0 && col <= 30 ) {  
    z = (col + 0.5)*pitchz;    
  } else if( col >= 31 && col <= 32) {  
    pitchz = 625;
    z = 13175 + (col -31 + 0.5)*pitchz;    
  } else if( col >= 33 && col <= 62) {  
    z = 14425 + (col -33 + 0.5)*pitchz;    
  } else if( col >= 63 && col <= 64) {  
    pitchz = 625;
    z = 27175 + (col -63 + 0.5)*pitchz;    
  } else if( col >= 65 && col <= 94) {  
    z = 28425 + (col -65 + 0.5)*pitchz;    
  } else if( col >= 95 && col <= 96) {  
    pitchz = 625;
    z = 41175 + (col -95 + 0.5)*pitchz;    
  } else if( col >= 97 && col <= 126) {  
    z = 42425 + (col -97 + 0.5)*pitchz;    
  } else if( col >= 127 && col <= 128) {  
    pitchz = 625;
    z = 55175 + (col -127 + 0.5)*pitchz;    
  } else if( col >= 129 && col <= 158) {  
    z = 56425 + (col -129 + 0.5)*pitchz;    
  } else if( col >= 159 && col <= 160) {  
    pitchz = 625;
    z = 69175 + (col -159 + 0.5)*pitchz;    
  } else if( col >= 161 && col <= 191) {  
    z = 70425 + (col -161 + 0.5)*pitchz;    
  }   

  return z;
}

Float_t ZpitchFromCol(Int_t col) {
// Get pitch size in z direction for each colunm

  Float_t pitchz = 425;
  if( col >=32 && col <= 33 ) {  
    pitchz = 625;
  } else if( col >= 64 && col <= 65) {  
    pitchz = 625;
  } else if( col >= 96 && col <= 97) {  
    pitchz = 625;
  } else if( col >= 128 && col <= 129) {  
    pitchz = 625;
  } else if( col >= 160 && col <= 161) {  
    pitchz = 625;
  }   
  return pitchz;
}

AliITSsegmentationSPD::AliITSsegmentationSPD(){
  // Default constructor
   fNpx = 0;
   fNpz = 0;
   fCorr=0;
   fGeom = 0;

}
//____________________________________________________________________________
AliITSsegmentationSPD::AliITSsegmentationSPD(AliITSgeom *gm){
  // Constructor
   fCorr=0;
   fNpx = 0;
   fNpz = 0;
   Init(); 
   fGeom = gm;

}
//____________________________________________________________________________
AliITSsegmentationSPD& AliITSsegmentationSPD::operator=(AliITSsegmentationSPD &source){
   // = operator
   if(this==&source) return *this;
   this->fNpx  = source.fNpx;
   this->fNpz  = source.fNpz;
   this->fDx   = source.fDx;
   this->fDy   = source.fDy;
   Int_t i;
   for(i=0;i<256;i++) this->fCellSizeX[i] = source.fCellSizeX[i];
   for(i=0;i<280;i++) this->fCellSizeZ[i] = source.fCellSizeZ[i];
   this->fCorr = new TF1(*(source.fCorr));// make a proper copy of the function
   this->fGeom = source.fGeom; // copy only the pointers.
   return *this;
}
//____________________________________________________________________________
AliITSsegmentationSPD::AliITSsegmentationSPD(AliITSsegmentationSPD &source){
  // copy constructor
   *this = source;
}
//------------------------------
void AliITSsegmentationSPD::Init300(){
// Initialize infromation for 6 read out chip 300X50 micron pixel SPD 
// detectors. This chip is 150 microns thick by 1.28 cm in x by 8.37 cm
// long. It has 256  50 micron pixels in x and 279 300 micron size
// pixels in z.

    //const Float_t kconv=10000.;
    Int_t i;
    fNpx = 256; // The number of X pixel Cell same as in fCellSizeX array size
    fNpz = 279; // The number of Z pixel Cell same as in fCellSizeZ array size
    for(i=0;i<fNpx;i++) fCellSizeX[i] = 50.0; // microns all the same
    for(i=0;i<fNpz;i++) fCellSizeZ[i] = ZpitchFromCol300(i); // microns
    for(i=fNpz;i<280;i++) fCellSizeZ[i] = 0.0; // zero out rest of array
    fDx = 0;
    for(i=0;i<fNpx;i++) fDx += fCellSizeX[i];
    fDz = 0;
    for(i=0;i<fNpz;i++) fDz += fCellSizeZ[i];
    fDy = 300.0; //microns  SPD sensitive layer thickness
}

//------------------------------
void AliITSsegmentationSPD::Init(){
// Initialize infromation for 6 read out chip 425X50 micron pixel SPD 
// detectors. This chip is 150 microns thick by 1.28 cm in x by 8.375 cm
// long. It has 256  50 micron pixels in x and 197 mostly 425 micron size
// pixels in z. The two pixels between each readout chip are 625 microns long.

    //const Float_t kconv=10000.;
    Int_t i;
    fNpx = 256; // The number of X pixel Cell same as in fCellSizeX array size
    fNpz = 192; // The number of Z pixel Cell same as in fCellSizeZ array size
    for(i=0;i<fNpx;i++) fCellSizeX[i] = 50.0; // microns all the same
    for(i=0;i<fNpz;i++) fCellSizeZ[i] = ZpitchFromCol(i); // microns
    for(i=fNpz;i<280;i++) fCellSizeZ[i] = 0.0; // zero out rest of array
    fDx = 0;
    for(i=0;i<fNpx;i++) fDx += fCellSizeX[i];
    fDz = 0;
    for(i=0;i<fNpz;i++) fDz += fCellSizeZ[i];
    fDy = 300.0; //microns  SPD sensitive layer thickness
    //printf(" AliITSsegmentationSPD - Init: fNpx fNpz fDx fDz %d %d %f %f\n",fNpx, fNpz, fDx, fDz);

}
//------------------------------
void AliITSsegmentationSPD::SetNPads(Int_t p1, Int_t p2){
  // for SPD this function should be used ONLY when a beam test setup 
  // configuration is studied

    fNpx=p1;
    fNpz=p2;

}
//------------------------------
void AliITSsegmentationSPD::SetDetSize(Float_t p1, Float_t p2, Float_t p3){
  // for SPD this function should be used ONLY when a beam test setup 
  // configuration is studied

    fDx=p1;
    fDz=p2;
    fDy=p3;

}
//------------------------------
Float_t AliITSsegmentationSPD::Dpx(Int_t i){
   //returs x pixel pitch for a give pixel
   return fCellSizeX[i];
}
//------------------------------
Float_t AliITSsegmentationSPD::Dpz(Int_t i){
  // returns z pixel pitch for a give pixel
   return ZpitchFromCol(i);
}
//------------------------------
void AliITSsegmentationSPD::GetPadIxz(Float_t x,Float_t z,Int_t &ix,Int_t &iz){
//  Returns pixel coordinates (ix,iz) for given real local coordinates (x,z)
//

    // expects x, z in microns

    // same segmentation on x
    Float_t dpx=Dpx(0);
    ix = (Int_t)(x/dpx + 1);
    // different segmentation on z
    iz = (Int_t)(ColFromZ(z) + 1);


    if (iz >  fNpz) iz= fNpz;
    if (ix >  fNpx) ix= fNpx;
    /*
    if (iz < -fNpz) iz= -fNpz;
    if (ix < -fNpx) ix=-fNpx;
    */
}

//------------------------------
void AliITSsegmentationSPD::GetPadTxz(Float_t &x,Float_t &z){
//  local transformation of real local coordinates (x,z)
//

    // expects x, z in microns

    // same segmentation on x
    Float_t dpx=Dpx(0);

    x /= dpx;
    z = ColFromZ(z);

}
//------------------------------
void AliITSsegmentationSPD::GetPadCxz(Int_t ix,Int_t iz,Float_t &x,Float_t&z){
    // Transform from pixel to real local coordinates

    // returns x, z in microns

    Float_t dpx=Dpx(0);

    x = (ix>0) ? Float_t(ix*dpx)-dpx/2. : Float_t(ix*dpx)+dpx/2.;
    z = ZFromCol(iz);


}
//------------------------------
void AliITSsegmentationSPD::
Neighbours(Int_t iX, Int_t iZ, Int_t* Nlist, Int_t Xlist[8], Int_t Zlist[8]){
  // returns the neighbouring pixels for use in Cluster Finders and the like.
  /*
    *Nlist=4;Xlist[0]=Xlist[1]=iX;Xlist[2]=iX-1;Xlist[3]=iX+1;
    Zlist[0]=iZ-1;Zlist[1]=iZ+1;Zlist[2]=Zlist[3]=iZ;
  */


    *Nlist=8;
    Xlist[0]=Xlist[1]=iX;
    Xlist[2]=iX-1;
    Xlist[3]=iX+1;
    Zlist[0]=iZ-1;
    Zlist[1]=iZ+1;
    Zlist[2]=Zlist[3]=iZ;

   // Diagonal elements
    Xlist[4]=iX+1;
    Zlist[4]=iZ+1;

    Xlist[5]=iX-1;
    Zlist[5]=iZ-1;

    Xlist[6]=iX-1;
    Zlist[6]=iZ+1;

    Xlist[7]=iX+1;
    Zlist[7]=iZ-1;
}
Commit	Line	Data
b0f5e3fc	1	/**************************************************************************
	2	* Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
	3	* *
	4	* Author: The ALICE Off-line Project. *
	5	* Contributors are mentioned in the code where appropriate. *
	6	* *
	7	* Permission to use, copy, modify and distribute this software and its *
	8	* documentation strictly for non-commercial purposes is hereby granted *
	9	* without fee, provided that the above copyright notice appears in all *
	10	* copies and that both the copyright notice and this permission notice *
	11	* appear in the supporting documentation. The authors make no claims *
	12	* about the suitability of this software for any purpose. It is *
	13	* provided "as is" without express or implied warranty. *
	14	**************************************************************************/
	15
	16	#include <TMath.h>
1ca7869b	17	#include <TF1.h>
b0f5e3fc	18
b0f5e3fc	19	#include "AliITSsegmentationSPD.h"
1ca7869b	20	#include "AliITSgeom.h"
b0f5e3fc	21
	22	ClassImp(AliITSsegmentationSPD)
	23
	24
	25	Float_t ColFromZ300(Float_t z) {
	26	// Get column number for each z-coordinate taking into account the
	27	// extra pixels in z direction assuming 300 micron sized pixels.
	28	Float_t col = 0.0;
	29	Float_t pitchz = 300.0;
	30	col = Float_t (z/pitchz);
	31	return col;
	32	}
	33	//_____________________________________________________________________________
	34	Float_t ZFromCol300(Int_t col) {
	35	// same comments as above
	36	// Get z-coordinate for each colunm number
	37	Float_t pitchz = 300.0;
	38	Float_t z = 0.0;
	39	z = (col+0.5)*pitchz;
	40	return z;
	41	}
	42	//_____________________________________________________________________________
	43	Float_t ZpitchFromCol300(Int_t col) {
	44	// returns Z pixel pitch for 300 micron pixels.
	45	return 300.0;
	46	}
	47	//_____________________________________________________________________________
	48	Float_t ColFromZ(Float_t z) {
	49	// hard-wired - keep it like this till we can parametrise
	50	// and get rid of AliITSgeomSPD425
	51	// Get column number for each z-coordinate taking into account the
	52	// extra pixels in z direction
	53
	54	Float_t col = 0;
	55	Float_t pitchz = 425;
	56	if( z < 13175) {
	57	col = Float_t(z/pitchz);
	58	} else if( z < 14425) {
	59	pitchz = 625;
	60	col = 31 + (z - 13175)/pitchz;
	61	} else if( z < 27175) {
	62	col = 33 + (z - 14425)/pitchz;
	63	} else if( z < 28425) {
	64	pitchz = 625;
	65	col = 63 + (z - 27175)/pitchz;
	66	} else if( z < 41175) {
	67	col = 65 + (z - 28425)/pitchz;
	68	} else if( z < 42425) {
	69	pitchz = 625;
	70	col = 95 + (z - 41175)/pitchz;
	71	} else if( z < 55175) {
	72	col = 97 + (z - 42425)/pitchz;
	73	} else if( z < 56425) {
	74	pitchz = 625;
	75	col = 127 + (z - 55175)/pitchz;
	76	} else if( z < 69175) {
	77	col = 129 + (z - 56425)/pitchz;
	78	} else if( z < 70425) {
	79	pitchz = 625;
	80	col = 159 + (z - 69175)/pitchz;
	81	} else if( z < 83600) {
	82	col = 161 + (z - 70425)/pitchz;
	83	}
e8189707	84	return TMath::Abs(col);
b0f5e3fc	85	}
	86
	87	//_____________________________________________________________________________
	88	Float_t ZFromCol(Int_t col) {
	89	// same comments as above
	90	// Get z-coordinate for each colunm number
	91
	92	Float_t pitchz = 425;
	93	Float_t z = 0;
	94	if( col >=0 && col <= 30 ) {
	95	z = (col + 0.5)*pitchz;
	96	} else if( col >= 31 && col <= 32) {
	97	pitchz = 625;
	98	z = 13175 + (col -31 + 0.5)*pitchz;
	99	} else if( col >= 33 && col <= 62) {
	100	z = 14425 + (col -33 + 0.5)*pitchz;
	101	} else if( col >= 63 && col <= 64) {
	102	pitchz = 625;
	103	z = 27175 + (col -63 + 0.5)*pitchz;
	104	} else if( col >= 65 && col <= 94) {
	105	z = 28425 + (col -65 + 0.5)*pitchz;
	106	} else if( col >= 95 && col <= 96) {
	107	pitchz = 625;
	108	z = 41175 + (col -95 + 0.5)*pitchz;
	109	} else if( col >= 97 && col <= 126) {
	110	z = 42425 + (col -97 + 0.5)*pitchz;
	111	} else if( col >= 127 && col <= 128) {
	112	pitchz = 625;
	113	z = 55175 + (col -127 + 0.5)*pitchz;
	114	} else if( col >= 129 && col <= 158) {
	115	z = 56425 + (col -129 + 0.5)*pitchz;
	116	} else if( col >= 159 && col <= 160) {
	117	pitchz = 625;
	118	z = 69175 + (col -159 + 0.5)*pitchz;
	119	} else if( col >= 161 && col <= 191) {
	120	z = 70425 + (col -161 + 0.5)*pitchz;
	121	}
	122
	123	return z;
	124	}
	125
	126	Float_t ZpitchFromCol(Int_t col) {
	127	// Get pitch size in z direction for each colunm
	128
	129	Float_t pitchz = 425;
	130	if( col >=32 && col <= 33 ) {
	131	pitchz = 625;
	132	} else if( col >= 64 && col <= 65) {
	133	pitchz = 625;
	134	} else if( col >= 96 && col <= 97) {
	135	pitchz = 625;
	136	} else if( col >= 128 && col <= 129) {
	137	pitchz = 625;
	138	} else if( col >= 160 && col <= 161) {
	139	pitchz = 625;
	140	}
	141	return pitchz;
	142	}
	143
	144	AliITSsegmentationSPD::AliITSsegmentationSPD(){
	145	// Default constructor
	146	fNpx = 0;
	147	fNpz = 0;
	148	fCorr=0;
149	fGeom = 0;
150
151	}
152	//____________________________________________________________________________
153	AliITSsegmentationSPD::AliITSsegmentationSPD(AliITSgeom *gm){
154	// Constructor
155	fCorr=0;
156	fNpx = 0;
157	fNpz = 0;
158	Init();
159	fGeom = gm;
160
161	}
162	//____________________________________________________________________________
163	AliITSsegmentationSPD& AliITSsegmentationSPD::operator=(AliITSsegmentationSPD &source){
164	// = operator
b0f5e3fc	165	if(this==&source) return *this;
	166	this->fNpx = source.fNpx;
	167	this->fNpz = source.fNpz;
	168	this->fDx = source.fDx;
	169	this->fDy = source.fDy;
e8189707	170	Int_t i;
b0f5e3fc	171	for(i=0;i<256;i++) this->fCellSizeX[i] = source.fCellSizeX[i];
	172	for(i=0;i<280;i++) this->fCellSizeZ[i] = source.fCellSizeZ[i];
	173	this->fCorr = new TF1(*(source.fCorr));// make a proper copy of the function
	174	this->fGeom = source.fGeom; // copy only the pointers.
	175	return *this;
	176	}
	177	//____________________________________________________________________________
	178	AliITSsegmentationSPD::AliITSsegmentationSPD(AliITSsegmentationSPD &source){
	179	// copy constructor
	180	*this = source;
	181	}
	182	//------------------------------
	183	void AliITSsegmentationSPD::Init300(){
	184	// Initialize infromation for 6 read out chip 300X50 micron pixel SPD
	185	// detectors. This chip is 150 microns thick by 1.28 cm in x by 8.37 cm
	186	// long. It has 256 50 micron pixels in x and 279 300 micron size
	187	// pixels in z.
	188
b0f5e3fc	189	//const Float_t kconv=10000.;
e8189707	190	Int_t i;
b0f5e3fc	191	fNpx = 256; // The number of X pixel Cell same as in fCellSizeX array size
	192	fNpz = 279; // The number of Z pixel Cell same as in fCellSizeZ array size
	193	for(i=0;i<fNpx;i++) fCellSizeX[i] = 50.0; // microns all the same
	194	for(i=0;i<fNpz;i++) fCellSizeZ[i] = ZpitchFromCol300(i); // microns
	195	for(i=fNpz;i<280;i++) fCellSizeZ[i] = 0.0; // zero out rest of array
	196	fDx = 0;
	197	for(i=0;i<fNpx;i++) fDx += fCellSizeX[i];
	198	fDz = 0;
	199	for(i=0;i<fNpz;i++) fDz += fCellSizeZ[i];
	200	fDy = 300.0; //microns SPD sensitive layer thickness
	201	}
	202
	203	//------------------------------
	204	void AliITSsegmentationSPD::Init(){
	205	// Initialize infromation for 6 read out chip 425X50 micron pixel SPD
	206	// detectors. This chip is 150 microns thick by 1.28 cm in x by 8.375 cm
	207	// long. It has 256 50 micron pixels in x and 197 mostly 425 micron size
	208	// pixels in z. The two pixels between each readout chip are 625 microns long.
	209
b0f5e3fc	210	//const Float_t kconv=10000.;
e8189707	211	Int_t i;
b0f5e3fc	212	fNpx = 256; // The number of X pixel Cell same as in fCellSizeX array size
	213	fNpz = 192; // The number of Z pixel Cell same as in fCellSizeZ array size
	214	for(i=0;i<fNpx;i++) fCellSizeX[i] = 50.0; // microns all the same
	215	for(i=0;i<fNpz;i++) fCellSizeZ[i] = ZpitchFromCol(i); // microns
	216	for(i=fNpz;i<280;i++) fCellSizeZ[i] = 0.0; // zero out rest of array
	217	fDx = 0;
	218	for(i=0;i<fNpx;i++) fDx += fCellSizeX[i];
	219	fDz = 0;
	220	for(i=0;i<fNpz;i++) fDz += fCellSizeZ[i];
	221	fDy = 300.0; //microns SPD sensitive layer thickness
e8189707	222	//printf(" AliITSsegmentationSPD - Init: fNpx fNpz fDx fDz %d %d %f %f\n",fNpx, fNpz, fDx, fDz);
b0f5e3fc	223
	224	}
	225	//------------------------------
e8189707	226	void AliITSsegmentationSPD::SetNPads(Int_t p1, Int_t p2){
b0f5e3fc	227	// for SPD this function should be used ONLY when a beam test setup
	228	// configuration is studied
	229
	230	fNpx=p1;
	231	fNpz=p2;
	232
	233	}
	234	//------------------------------
	235	void AliITSsegmentationSPD::SetDetSize(Float_t p1, Float_t p2, Float_t p3){
	236	// for SPD this function should be used ONLY when a beam test setup
	237	// configuration is studied
	238
	239	fDx=p1;
	240	fDz=p2;
	241	fDy=p3;
	242
	243	}
	244	//------------------------------
	245	Float_t AliITSsegmentationSPD::Dpx(Int_t i){
	246	//returs x pixel pitch for a give pixel
	247	return fCellSizeX[i];
	248	}
	249	//------------------------------
	250	Float_t AliITSsegmentationSPD::Dpz(Int_t i){
	251	// returns z pixel pitch for a give pixel
	252	return ZpitchFromCol(i);
	253	}
	254	//------------------------------
e8189707	255	void AliITSsegmentationSPD::GetPadIxz(Float_t x,Float_t z,Int_t &ix,Int_t &iz){
b0f5e3fc	256	// Returns pixel coordinates (ix,iz) for given real local coordinates (x,z)
	257	//
	258
	259	// expects x, z in microns
	260
	261	// same segmentation on x
	262	Float_t dpx=Dpx(0);
	263	ix = (Int_t)(x/dpx + 1);
	264	// different segmentation on z
	265	iz = (Int_t)(ColFromZ(z) + 1);
	266
b0f5e3fc	267
	268	if (iz > fNpz) iz= fNpz;
	269	if (ix > fNpx) ix= fNpx;
b0f5e3fc	270	/*
	271	if (iz < -fNpz) iz= -fNpz;
	272	if (ix < -fNpx) ix=-fNpx;
	273	*/
	274	}
	275
	276	//------------------------------
e8189707	277	void AliITSsegmentationSPD::GetPadTxz(Float_t &x,Float_t &z){
	278	// local transformation of real local coordinates (x,z)
	279	//
	280
	281	// expects x, z in microns
	282
	283	// same segmentation on x
	284	Float_t dpx=Dpx(0);
	285
	286	x /= dpx;
	287	z = ColFromZ(z);
	288
	289	}
	290	//------------------------------
	291	void AliITSsegmentationSPD::GetPadCxz(Int_t ix,Int_t iz,Float_t &x,Float_t&z){
b0f5e3fc	292	// Transform from pixel to real local coordinates
	293
	294	// returns x, z in microns
	295
	296	Float_t dpx=Dpx(0);
	297
	298	x = (ix>0) ? Float_t(ixdpx)-dpx/2. : Float_t(ixdpx)+dpx/2.;
	299	z = ZFromCol(iz);
	300
	301
	302	}
	303	//------------------------------
	304	void AliITSsegmentationSPD::
	305	Neighbours(Int_t iX, Int_t iZ, Int_t* Nlist, Int_t Xlist[8], Int_t Zlist[8]){
	306	// returns the neighbouring pixels for use in Cluster Finders and the like.
	307	/*
	308	*Nlist=4;Xlist[0]=Xlist[1]=iX;Xlist[2]=iX-1;Xlist[3]=iX+1;
	309	Zlist[0]=iZ-1;Zlist[1]=iZ+1;Zlist[2]=Zlist[3]=iZ;
	310	*/
	311
	312
	313	*Nlist=8;
	314	Xlist[0]=Xlist[1]=iX;
	315	Xlist[2]=iX-1;
	316	Xlist[3]=iX+1;
	317	Zlist[0]=iZ-1;
	318	Zlist[1]=iZ+1;
	319	Zlist[2]=Zlist[3]=iZ;
	320
	321	// Diagonal elements
	322	Xlist[4]=iX+1;
	323	Zlist[4]=iZ+1;
	324
	325	Xlist[5]=iX-1;
	326	Zlist[5]=iZ-1;
	327
	328	Xlist[6]=iX-1;
	329	Zlist[6]=iZ+1;
	330
	331	Xlist[7]=iX+1;
	332	Zlist[7]=iZ-1;
	333	}