[u/mrichter/AliRoot.git] / STEER / AliLego.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.                  *
 **************************************************************************/

/*
$Log$
Revision 1.10  2000/02/23 16:25:22  fca
AliVMC and AliGeant3 classes introduced
ReadEuclid moved from AliRun to AliModule

Revision 1.9  1999/12/03 10:54:01  fca
Fix lego summary

Revision 1.8  1999/10/01 09:54:33  fca
Correct logics for Lego StepManager

Revision 1.7  1999/09/29 09:24:29  fca
Introduction of the Copyright and cvs Log

*/

//////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////
//                            
//  Utility class to evaluate the material budget from
//  a given radius to the surface of an arbitrary cylinder
//  along radial directions from the centre:
// 
//   - radiation length
//   - Interaction length
//   - g/cm2
// 
//  Geantinos are shot in the bins in the fNtheta bins in theta
//  and fNphi bins in phi with specified rectangular limits.
//  The statistics are accumulated per
//    fRadMin < r < fRadMax    and  <0 < z < fZMax
//
//  To activate this option, you can do:
//      Root > gAlice.RunLego();
//  or  Root > .x menu.C  then select menu item "RunLego"
//  Note that when calling gAlice->RunLego, an optional list
//  of arguments may be specified.
//
//Begin_Html
/*
<img src="picts/alilego.gif">
*/
//End_Html
//
//////////////////////////////////////////////////////////////

#include "TMath.h"
#include "AliLego.h"
#include "AliRun.h"
#include "AliConst.h"
#include "AliVMC.h"

ClassImp(AliLego)


//___________________________________________
AliLego::AliLego()
{
   fHistRadl = 0;
   fHistAbso = 0;
   fHistGcm2 = 0;
   fHistReta = 0;
}

//___________________________________________
AliLego::AliLego(const char *title, Int_t ntheta, Float_t themin, Float_t themax,
		 Int_t nphi, Float_t phimin, Float_t phimax,
		 Float_t rmin, Float_t rmax, Float_t zmax)
  : TNamed("Lego Generator",title)
{
// specify the angular limits and the size of the rectangular box
   
   fGener = new AliLegoGenerator(ntheta, themin, themax,
		       nphi, phimin, phimax, rmin, rmax, zmax);
   
   gAlice->ResetGenerator(fGener);

   Float_t etamin = -TMath::Log(TMath::Tan(TMath::Min((Double_t)themax*kDegrad/2,TMath::Pi()/2-1.e-10)));
   Float_t etamax = -TMath::Log(TMath::Tan(TMath::Max((Double_t)themin*kDegrad/2,              1.e-10)));

   fHistRadl = new TH2F("hradl","Radiation length map",    
			nphi,phimin,phimax,ntheta,themin,themax);
   fHistAbso = new TH2F("habso","Interaction length map",  
			nphi,phimin,phimax,ntheta,themin,themax);
   fHistGcm2 = new TH2F("hgcm2","g/cm2 length map",        
			nphi,phimin,phimax,ntheta,themin,themax);
   fHistReta = new TH2F("hetar","Radiation length vs. eta",
			nphi,phimin,phimax,ntheta,etamin,etamax);

}

//___________________________________________
AliLego::~AliLego()
{
   delete fHistRadl;
   delete fHistAbso;
   delete fHistGcm2;
   delete fHistReta;
}


//___________________________________________
void AliLego::Run()
{
   // loop on phi,theta bins
   gMC->InitLego();
   Float_t thed, phid, eta;
   for (Int_t i=0; i<=fGener->Nphi()*fGener->Ntheta(); ++i) {
// --- Set to 0 radiation length, absorption length and g/cm2 ---
     fTotRadl = 0;
     fTotAbso = 0;
     fTotGcm2 = 0;
     
     gVMC->ProcessEvent();
     
     thed = fGener->CurTheta()*kRaddeg;
     phid = fGener->CurPhi()*kRaddeg;
     eta  = -TMath::Log(TMath::Tan(TMath::Max(
	     TMath::Min((Double_t)(fGener->CurTheta())/2,
			TMath::Pi()/2-1.e-10),1.e-10)));

     fHistRadl->Fill(phid,thed,fTotRadl);
     fHistAbso->Fill(phid,thed,fTotAbso);
     fHistGcm2->Fill(phid,thed,fTotGcm2);
     fHistReta->Fill(phid,eta,fTotRadl);
     gAlice->FinishEvent();
   }
   // store histograms in current Root file
   fHistRadl->Write();
   fHistAbso->Write();
   fHistGcm2->Write();
   fHistReta->Write();
}

//___________________________________________
void AliLego::StepManager()
{
// called from AliRun::Stepmanager from gustep.
// Accumulate the 3 parameters step by step
  
   static Float_t t;
   Float_t a,z,dens,radl,absl;
   Int_t i;
   
   Float_t step  = gMC->TrackStep();
       
   Float_t vect[3], dir[3];
   TLorentzVector pos, mom;

   gMC->TrackPosition(pos);  
   gMC->TrackMomentum(mom);
   gMC->CurrentMaterial(a,z,dens,radl,absl);
   
   if (z < 1) return;
   
// --- See if we have to stop now
   if (TMath::Abs(pos[2]) > fGener->ZMax()  || 
       pos[0]*pos[0] +pos[1]*pos[1] > fGener->RadMax()*fGener->RadMax()) {
     if (gMC->TrackLength()) {
       // Not the first step, add past contribution
       fTotAbso += t/absl;
       fTotRadl += t/radl;
       fTotGcm2 += t*dens;
     }
     gMC->StopTrack();
     return;
   }

// --- See how long we have to go
   for(i=0;i<3;++i) {
     vect[i]=pos[i];
     dir[i]=mom[i];
   }

   t  = fGener->PropagateCylinder(vect,dir,fGener->RadMax(),fGener->ZMax());

   if(step) {
     fTotAbso += step/absl;
     fTotRadl += step/radl;
     fTotGcm2 += step*dens;
   }
}

ClassImp(AliLegoGenerator)

//___________________________________________
AliLegoGenerator::AliLegoGenerator(Int_t ntheta, Float_t themin,
				   Float_t themax, Int_t nphi, 
				   Float_t phimin, Float_t phimax,
				   Float_t rmin, Float_t rmax, Float_t zmax) :
  AliGenerator(0), fRadMin(rmin), fRadMax(rmax), fZMax(zmax), fNtheta(ntheta),
  fNphi(nphi), fThetaBin(ntheta), fPhiBin(-1), fCurTheta(0), fCurPhi(0)
  
{
  SetPhiRange(phimin,phimax);
  SetThetaRange(themin,themax);
  SetName("Lego");
}


//___________________________________________
void AliLegoGenerator::Generate()
{
// Create a geantino with kinematics corresponding to the current
// bins in theta and phi.
   
  //
  // Rootinos are 0
   const Int_t mpart = 0;
   Float_t orig[3], pmom[3];
   Float_t t, cost, sint, cosp, sinp;
   
   // Prepare for next step
   if(fThetaBin>=fNtheta-1)
     if(fPhiBin>=fNphi-1) {
       Warning("Generate","End of Lego Generation");
       return;
     } else { 
       fPhiBin++;
       printf("Generating rays in phi bin:%d\n",fPhiBin);
       fThetaBin=0;
     } else fThetaBin++;

   fCurTheta = (fThetaMin+(fThetaBin+0.5)*(fThetaMax-fThetaMin)/fNtheta);
   fCurPhi   = (fPhiMin+(fPhiBin+0.5)*(fPhiMax-fPhiMin)/fNphi);
   cost      = TMath::Cos(fCurTheta);
   sint      = TMath::Sin(fCurTheta);
   cosp      = TMath::Cos(fCurPhi);
   sinp      = TMath::Sin(fCurPhi);
   
   pmom[0] = cosp*sint;
   pmom[1] = sinp*sint;
   pmom[2] = cost;
   
   // --- Where to start
   orig[0] = orig[1] = orig[2] = 0;
   Float_t dalicz = 3000;
   if (fRadMin > 0) {
     t = PropagateCylinder(orig,pmom,fRadMin,dalicz);
     orig[0] = pmom[0]*t;
     orig[1] = pmom[1]*t;
     orig[2] = pmom[2]*t;
     if (TMath::Abs(orig[2]) > fZMax) return;
   }
   
   Float_t polar[3]={0.,0.,0.};
   Int_t ntr;
   gAlice->SetTrack(1, 0, mpart, pmom, orig, polar, 0, "LEGO ray", ntr);

}

//___________________________________________
Float_t AliLegoGenerator::PropagateCylinder(Float_t *x, Float_t *v, Float_t r, Float_t z)
{
// Propagate to cylinder from inside

   Double_t hnorm, sz, t, t1, t2, t3, sr;
   Double_t d[3];
   const Float_t kSmall  = 1e-8;
   const Float_t kSmall2 = kSmall*kSmall;

// ---> Find intesection with Z planes
   d[0]  = v[0];
   d[1]  = v[1];
   d[2]  = v[2];
   hnorm = TMath::Sqrt(1/(d[0]*d[0]+d[1]*d[1]+d[2]*d[2]));
   d[0] *= hnorm;
   d[1] *= hnorm;
   d[2] *= hnorm;
   if (d[2] > kSmall)       sz = (z-x[2])/d[2];
   else if (d[2] < -kSmall) sz = -(z+x[2])/d[2];
   else                     sz = 1.e10;  // ---> Direction parallel to X-Y, no intersection

// ---> Intersection with cylinders
//      Intersection point (x,y,z)
//      (x,y,z) is on track :    x=X(1)+t*D(1)
//                               y=X(2)+t*D(2)
//                               z=X(3)+t*D(3)
//      (x,y,z) is on cylinder : x**2 + y**2 = R**2
//
//      (D(1)**2+D(2)**2)*t**2
//      +2.*(X(1)*D(1)+X(2)*D(2))*t
//      +X(1)**2+X(2)**2-R**2=0
// ---> Solve second degree equation
   t1 = d[0]*d[0] + d[1]*d[1];
   if (t1 <= kSmall2) {
      t = sz;  // ---> Track parallel to the z-axis, take distance to planes
   } else {
      t2 = x[0]*d[0] + x[1]*d[1];
      t3 = x[0]*x[0] + x[1]*x[1];
      // ---> It should be positive, but there may be numerical problems
      sr = (t2 +TMath::Sqrt(TMath::Max(t2*t2-(t3-r*r)*t1,0.)))/t1;
      // ---> Find minimum distance between planes and cylinder
      t  = TMath::Min(sz,sr);
   }
   return t;
}
Commit	Line	Data
4c039060	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	/*
	17	$Log$
ee1dd322	18	Revision 1.10 2000/02/23 16:25:22 fca
	19	AliVMC and AliGeant3 classes introduced
	20	ReadEuclid moved from AliRun to AliModule
	21
b13db077	22	Revision 1.9 1999/12/03 10:54:01 fca
	23	Fix lego summary
	24
00719c1b	25	Revision 1.8 1999/10/01 09:54:33 fca
	26	Correct logics for Lego StepManager
	27
f059c84a	28	Revision 1.7 1999/09/29 09:24:29 fca
	29	Introduction of the Copyright and cvs Log
	30
4c039060	31	*/
4c039060	32
fe4da5cc	33	//////////////////////////////////////////////////////////////
	34	//////////////////////////////////////////////////////////////
	35	//
	36	// Utility class to evaluate the material budget from
	37	// a given radius to the surface of an arbitrary cylinder
	38	// along radial directions from the centre:
	39	//
	40	// - radiation length
	41	// - Interaction length
	42	// - g/cm2
	43	//
	44	// Geantinos are shot in the bins in the fNtheta bins in theta
	45	// and fNphi bins in phi with specified rectangular limits.
	46	// The statistics are accumulated per
	47	// fRadMin < r < fRadMax and <0 < z < fZMax
	48	//
	49	// To activate this option, you can do:
	50	// Root > gAlice.RunLego();
	51	// or Root > .x menu.C then select menu item "RunLego"
	52	// Note that when calling gAlice->RunLego, an optional list
	53	// of arguments may be specified.
	54	//
	55	//Begin_Html
	56	/*
1439f98e	57	<img src="picts/alilego.gif">
fe4da5cc	58	*/
	59	//End_Html
	60	//
	61	//////////////////////////////////////////////////////////////
	62
	63	#include "TMath.h"
1578254f	64	#include "AliLego.h"
fe4da5cc	65	#include "AliRun.h"
fe4da5cc	66	#include "AliConst.h"
b13db077	67	#include "AliVMC.h"
fe4da5cc	68
	69	ClassImp(AliLego)
	70
	71
	72	//___________________________________________
	73	AliLego::AliLego()
	74	{
	75	fHistRadl = 0;
	76	fHistAbso = 0;
	77	fHistGcm2 = 0;
	78	fHistReta = 0;
	79	}
	80
	81	//___________________________________________
b13db077	82	AliLego::AliLego(const char *title, Int_t ntheta, Float_t themin, Float_t themax,
	83	Int_t nphi, Float_t phimin, Float_t phimax,
	84	Float_t rmin, Float_t rmax, Float_t zmax)
	85	: TNamed("Lego Generator",title)
fe4da5cc	86	{
b13db077	87	// specify the angular limits and the size of the rectangular box
	88
	89	fGener = new AliLegoGenerator(ntheta, themin, themax,
	90	nphi, phimin, phimax, rmin, rmax, zmax);
	91
ee1dd322	92	gAlice->ResetGenerator(fGener);
b13db077	93
	94	Float_t etamin = -TMath::Log(TMath::Tan(TMath::Min((Double_t)themax*kDegrad/2,TMath::Pi()/2-1.e-10)));
	95	Float_t etamax = -TMath::Log(TMath::Tan(TMath::Max((Double_t)themin*kDegrad/2, 1.e-10)));
	96
	97	fHistRadl = new TH2F("hradl","Radiation length map",
	98	nphi,phimin,phimax,ntheta,themin,themax);
	99	fHistAbso = new TH2F("habso","Interaction length map",
	100	nphi,phimin,phimax,ntheta,themin,themax);
	101	fHistGcm2 = new TH2F("hgcm2","g/cm2 length map",
	102	nphi,phimin,phimax,ntheta,themin,themax);
	103	fHistReta = new TH2F("hetar","Radiation length vs. eta",
	104	nphi,phimin,phimax,ntheta,etamin,etamax);
	105
fe4da5cc	106	}
	107
	108	//___________________________________________
	109	AliLego::~AliLego()
	110	{
	111	delete fHistRadl;
	112	delete fHistAbso;
	113	delete fHistGcm2;
	114	delete fHistReta;
	115	}
	116
b13db077	117
	118	//___________________________________________
	119	void AliLego::Run()
	120	{
	121	// loop on phi,theta bins
	122	gMC->InitLego();
	123	Float_t thed, phid, eta;
	124	for (Int_t i=0; i<=fGener->Nphi()*fGener->Ntheta(); ++i) {
	125	// --- Set to 0 radiation length, absorption length and g/cm2 ---
	126	fTotRadl = 0;
	127	fTotAbso = 0;
	128	fTotGcm2 = 0;
	129
	130	gVMC->ProcessEvent();
	131
	132	thed = fGener->CurTheta()*kRaddeg;
	133	phid = fGener->CurPhi()*kRaddeg;
	134	eta = -TMath::Log(TMath::Tan(TMath::Max(
	135	TMath::Min((Double_t)(fGener->CurTheta())/2,
	136	TMath::Pi()/2-1.e-10),1.e-10)));
	137
	138	fHistRadl->Fill(phid,thed,fTotRadl);
	139	fHistAbso->Fill(phid,thed,fTotAbso);
	140	fHistGcm2->Fill(phid,thed,fTotGcm2);
	141	fHistReta->Fill(phid,eta,fTotRadl);
	142	gAlice->FinishEvent();
	143	}
	144	// store histograms in current Root file
	145	fHistRadl->Write();
	146	fHistAbso->Write();
	147	fHistGcm2->Write();
	148	fHistReta->Write();
	149	}
	150
	151	//___________________________________________
	152	void AliLego::StepManager()
	153	{
	154	// called from AliRun::Stepmanager from gustep.
	155	// Accumulate the 3 parameters step by step
	156
	157	static Float_t t;
	158	Float_t a,z,dens,radl,absl;
	159	Int_t i;
	160
	161	Float_t step = gMC->TrackStep();
	162
	163	Float_t vect[3], dir[3];
	164	TLorentzVector pos, mom;
	165
	166	gMC->TrackPosition(pos);
	167	gMC->TrackMomentum(mom);
	168	gMC->CurrentMaterial(a,z,dens,radl,absl);
	169
	170	if (z < 1) return;
	171
	172	// --- See if we have to stop now
	173	if (TMath::Abs(pos[2]) > fGener->ZMax() \|\|
	174	pos[0]pos[0] +pos[1]pos[1] > fGener->RadMax()*fGener->RadMax()) {
	175	if (gMC->TrackLength()) {
	176	// Not the first step, add past contribution
	177	fTotAbso += t/absl;
	178	fTotRadl += t/radl;
	179	fTotGcm2 += t*dens;
	180	}
181	gMC->StopTrack();
182	return;
183	}
184
185	// --- See how long we have to go
186	for(i=0;i<3;++i) {
187	vect[i]=pos[i];
188	dir[i]=mom[i];
189	}
190
191	t = fGener->PropagateCylinder(vect,dir,fGener->RadMax(),fGener->ZMax());
192
193	if(step) {
194	fTotAbso += step/absl;
195	fTotRadl += step/radl;
196	fTotGcm2 += step*dens;
197	}
198	}
199
200	ClassImp(AliLegoGenerator)
201
202	//___________________________________________
203	AliLegoGenerator::AliLegoGenerator(Int_t ntheta, Float_t themin,
204	Float_t themax, Int_t nphi,
205	Float_t phimin, Float_t phimax,
206	Float_t rmin, Float_t rmax, Float_t zmax) :
207	AliGenerator(0), fRadMin(rmin), fRadMax(rmax), fZMax(zmax), fNtheta(ntheta),
208	fNphi(nphi), fThetaBin(ntheta), fPhiBin(-1), fCurTheta(0), fCurPhi(0)
209
210	{
211	SetPhiRange(phimin,phimax);
212	SetThetaRange(themin,themax);
213	SetName("Lego");
214	}
215
216
fe4da5cc	217	//___________________________________________
b13db077	218	void AliLegoGenerator::Generate()
fe4da5cc	219	{
	220	// Create a geantino with kinematics corresponding to the current
	221	// bins in theta and phi.
	222
1578254f	223	//
	224	// Rootinos are 0
	225	const Int_t mpart = 0;
fe4da5cc	226	Float_t orig[3], pmom[3];
	227	Float_t t, cost, sint, cosp, sinp;
	228
b13db077	229	// Prepare for next step
	230	if(fThetaBin>=fNtheta-1)
	231	if(fPhiBin>=fNphi-1) {
	232	Warning("Generate","End of Lego Generation");
	233	return;
	234	} else {
	235	fPhiBin++;
	236	printf("Generating rays in phi bin:%d\n",fPhiBin);
	237	fThetaBin=0;
	238	} else fThetaBin++;
fe4da5cc	239
b13db077	240	fCurTheta = (fThetaMin+(fThetaBin+0.5)*(fThetaMax-fThetaMin)/fNtheta);
b13db077	241	fCurPhi = (fPhiMin+(fPhiBin+0.5)*(fPhiMax-fPhiMin)/fNphi);
fe4da5cc	242	cost = TMath::Cos(fCurTheta);
	243	sint = TMath::Sin(fCurTheta);
	244	cosp = TMath::Cos(fCurPhi);
	245	sinp = TMath::Sin(fCurPhi);
b13db077	246
fe4da5cc	247	pmom[0] = cosp*sint;
	248	pmom[1] = sinp*sint;
	249	pmom[2] = cost;
b13db077	250
b13db077	251	// --- Where to start
fe4da5cc	252	orig[0] = orig[1] = orig[2] = 0;
	253	Float_t dalicz = 3000;
	254	if (fRadMin > 0) {
b13db077	255	t = PropagateCylinder(orig,pmom,fRadMin,dalicz);
	256	orig[0] = pmom[0]*t;
	257	orig[1] = pmom[1]*t;
	258	orig[2] = pmom[2]*t;
	259	if (TMath::Abs(orig[2]) > fZMax) return;
fe4da5cc	260	}
b13db077	261
fe4da5cc	262	Float_t polar[3]={0.,0.,0.};
	263	Int_t ntr;
	264	gAlice->SetTrack(1, 0, mpart, pmom, orig, polar, 0, "LEGO ray", ntr);
fe4da5cc	265
	266	}
	267
	268	//___________________________________________
b13db077	269	Float_t AliLegoGenerator::PropagateCylinder(Float_t x, Float_t v, Float_t r, Float_t z)
fe4da5cc	270	{
	271	// Propagate to cylinder from inside
	272
	273	Double_t hnorm, sz, t, t1, t2, t3, sr;
	274	Double_t d[3];
	275	const Float_t kSmall = 1e-8;
	276	const Float_t kSmall2 = kSmall*kSmall;
	277
	278	// ---> Find intesection with Z planes
	279	d[0] = v[0];
	280	d[1] = v[1];
	281	d[2] = v[2];
	282	hnorm = TMath::Sqrt(1/(d[0]d[0]+d[1]d[1]+d[2]*d[2]));
	283	d[0] *= hnorm;
	284	d[1] *= hnorm;
	285	d[2] *= hnorm;
	286	if (d[2] > kSmall) sz = (z-x[2])/d[2];
	287	else if (d[2] < -kSmall) sz = -(z+x[2])/d[2];
	288	else sz = 1.e10; // ---> Direction parallel to X-Y, no intersection
	289
	290	// ---> Intersection with cylinders
	291	// Intersection point (x,y,z)
	292	// (x,y,z) is on track : x=X(1)+t*D(1)
	293	// y=X(2)+t*D(2)
	294	// z=X(3)+t*D(3)
	295	// (x,y,z) is on cylinder : x2 + y2 = R**2
	296	//
	297	// (D(1)2+D(2)2)t*2
	298	// +2.(X(1)D(1)+X(2)D(2))t
	299	// +X(1)2+X(2)2-R**2=0
	300	// ---> Solve second degree equation
	301	t1 = d[0]d[0] + d[1]d[1];
	302	if (t1 <= kSmall2) {
	303	t = sz; // ---> Track parallel to the z-axis, take distance to planes
	304	} else {
	305	t2 = x[0]d[0] + x[1]d[1];
	306	t3 = x[0]x[0] + x[1]x[1];
	307	// ---> It should be positive, but there may be numerical problems
	308	sr = (t2 +TMath::Sqrt(TMath::Max(t2t2-(t3-rr)*t1,0.)))/t1;
	309	// ---> Find minimum distance between planes and cylinder
	310	t = TMath::Min(sz,sr);
	311	}
	312	return t;
	313	}
	314