void extractTree(const char *file, int event_num) {
TFile *f = new TFile(file);
TTree *tree = (TTree*) f->Get("T");
RAT::DS::Root *rds = new RAT::DS::Root();
tree->SetBranchAddress("ds", &rds);
tree->GetEntry(event_num);
RAT::DS::MC *mc = rds->GetMC();
int nTracks = mc->GetMCTrackCount();
Particle *trackmap = new Particle[nTracks+1];
for (int j = 0; j < nTracks; j++) {
RAT::DS::MCTrack *track = mc->GetMCTrack(j);
int tid = track->GetID();
int pid = track->GetParentID();
Particle *cur = &trackmap[tid];
trackmap[pid].addChild(cur);
RAT::DS::MCTrackStep *first = track->GetMCTrackStep(0);
RAT::DS::MCTrackStep *last = track->GetLastMCTrackStep();
int nSteps = track->GetMCTrackStepCount();
TVector3 *steps = new TVector3[nSteps];
for (int k = 0; k < nSteps; k++) {
steps[k] = track->GetMCTrackStep(k)->GetEndpoint();
}
cur->setProperties(track->GetParticleName(),first->GetProcess(),last->GetProcess(),steps,nSteps);
}
trackmap[1].dumpList(cout);
}
TTree* GrowJoinedPhotonTree( RAT::DSReader& theDS )
{
//Now we build the fundamental blocks of our operation. The TrackedOpticalPhoton is static to avoid
//building many copies of the object on the stack, which is unnecessary. We reset the photon at the
//end of each track for this reason.
RAT::DS::Root* theDSEvent = NULL;
RAT::DS::MC* theDSMC = NULL;
static TrackedOpticalPhoton thePhoton;
TTree* theResultingTree = new TTree("T",
"Data From Tracked Optical Photons");
//For ROOT compatibility. For versions 5.22 and up, it's legal to omit the
//name of the class in this call. Before then, we need to call it by name.
#ifdef __ROOTVERLT522
TBranch* theBranch = theResultingTree->Branch("TrackedOpticalPhotons",
"TrackedOpticalPhoton",&thePhoton);
#else
TBranch* theBranch = theResultingTree->Branch("TrackedOpticalPhotons",
&thePhoton);
#endif
//This is just to keep the compiler from complaining about the use of the
//TBranch.
theBranch->UpdateAddress();
//All we are going to do, for starters, is get the tracks, print out the
//steps, join the tracks, and print them out again. Easy stuff. This will
//also give an easy way to track where the code is going wrong (or right).
for ( int eventIndex = 0; eventIndex < theDS.GetTotal(); eventIndex++ )
{
//Move to the next event.
theDSEvent = theDS.GetEvent(eventIndex);
theDSMC = theDSEvent->GetMC();
#ifndef CLUSTER_RUN
//Spit out Event Info...
std::cout << std::endl << "Analyzing event " << eventIndex << std::endl;
#endif
//The container will be a map, where the key is the trackID and the
//value is the track itself. This structure is _very_ useful for
//track reconstruction, where you want to be able to get a track by
//referring to its id.
IDtoTrackMap tracks;
//We also want to have a container that can tell us if a given track
//caused a hit in the simulation. We use a vector<bool>, where the
//index is equal to the trackID.
std::vector<bool> hit_list( theDSMC->GetMCTrackCount(), false );
//Now fill the map with the tracks.
for ( int track = 0; track < theDSMC->GetMCTrackCount(); track++ )
{
//Check if the track is an optical photon.
if ( theDSMC->GetMCTrack(track)->GetParticleName() == "opticalphoton" )
{
//Grab the track out of the monte carlo and push it into the map
//with its ID.
RAT::DS::MCTrack newTrack = *theDSMC->GetMCTrack(track);
tracks.insert( IDwithTrack(newTrack.GetTrackID(), newTrack) );
}
}
//And now for every hit in the monte carlo, flip the appropriate bit.
for ( int mc_pmt_hit = 0; mc_pmt_hit < theDSMC->GetMCPMTCount(); mc_pmt_hit++ )
{
//Iterate through all MCPhotons, flipping the TrackID'th bit in the vector<bool>
//to indicate a hit.
for ( int mc_phot = 0; mc_phot < theDSMC->GetMCPMT(mc_pmt_hit)->GetMCPhotonCount(); mc_phot++ )
{
hit_list[ theDSMC->GetMCPMT(mc_pmt_hit)->GetMCPhoton(mc_phot)->GetTrackID() - 1 ].flip();
}
}
#ifndef CLUSTER_RUN
#ifdef PRINT_TRACK_DEBUG
//Now that our map is full of tracks, let's iterate over them and
//print out their information. This is, of course, pre-joining.
IDtoTrackMap::iterator track_it = tracks.begin();
while ( track_it != tracks.end() )
{
std::cout << "Track ID " << track_it->first << "->Child of track ID " << track_it->second.GetParentID() << "\n";
for ( std::size_t stepcount = 0; stepcount < track_it->second.GetMCTrackStepCount(); stepcount++ )
{
std::cout << "\t Step " << stepcount << "->" << track_it->second.GetMCTrackStep(stepcount)->GetProcess() << "\n"
<< "\t\t X:" << track_it->second.GetMCTrackStep(stepcount)->GetEndpoint().X() << "\n"
<< "\t\t Y:" << track_it->second.GetMCTrackStep(stepcount)->GetEndpoint().Y() << "\n"
<< "\t\t Z:" << track_it->second.GetMCTrackStep(stepcount)->GetEndpoint().Z() << "\n"
<< "\t\t T:" << track_it->second.GetMCTrackStep(stepcount)->GetGlobalTime() << "\n"
<< "\t\t KE:" << track_it->second.GetMCTrackStep(stepcount)->GetKE() << std::endl;
}
//Remember to increment the iterator!
track_it++;
}
#endif
#endif
//OK, now the hard work. We need to join these damn tracks. Use a
//reverse iterator to move back through the tracks and look for child-
//parent relationships. This will simplify the logic of removing tracks
//from the map that 'belong' to some parent.
IDtoTrackMap::reverse_iterator track_rit = tracks.rbegin();
while ( track_rit != tracks.rend() )
{
//Search for the ID of the parent track in the map. If it is found,
//we have work to do.
IDtoTrackMap::iterator mall_guard = tracks.find( track_rit->second.GetParentID() );
if ( mall_guard != tracks.end() )
{
//Create a vector of the tracks that are related, and start looking
//to see if they have parents of their own.
std::vector<RAT::DS::MCTrack> estranged_tracks;
estranged_tracks.push_back( mall_guard->second );
estranged_tracks.push_back( track_rit->second );
mall_guard = tracks.find( mall_guard->second.GetParentID() );
while ( mall_guard != tracks.end() )
{
estranged_tracks.push_back( mall_guard->second );
mall_guard = tracks.find( mall_guard->second.GetParentID() );
}
//Now here's the trick. The original tracks need to be
//__removed__ from the track listing. Otherwise, when we step
//to the next track, we are going to have issues due to the
//fact that they are tracks in the chain. Of course, this is
//fine, because we have retained all of the information they
//had anyhow. While we are doing this, we want to check to see
//if any of the tracks caused hits in the monte carlo. If they
//did, we need to flip the new bit in the hitlist.
std::vector<RAT::DS::MCTrack>::iterator est_it = estranged_tracks.begin();
bool ChildHit(false);
while ( est_it != estranged_tracks.end() )
{
unsigned theChildID = est_it->GetTrackID();
if ( hit_list[theChildID - 1] )
{
//Mark the flag and unset the hitlist for the child.
ChildHit = true;
hit_list[theChildID - 1].flip();
}
tracks.erase( tracks.find(theChildID)->first );
est_it++;
}
//Now we should have all of the parents. Assemble them via
//the JoinMCTracks function. For now, just stick it on the end
//of the tracks we've already made.
RAT::DS::MCTrack joined = JoinMCTracks(estranged_tracks);
tracks.insert( IDwithTrack(joined.GetTrackID(),joined) );
//If the ChildHit bit is flipped, make sure that the trackID of
//the new joined track gets set.
if ( ChildHit ) hit_list[ joined.GetTrackID() - 1 ].flip();
//Now the iterator needs to be reset, because we've deleted elements
//from the map, which _should_ invalidate the pointer, but it
//doesn't because find() returns a forward iterator.
track_rit = tracks.rbegin();
}
else track_rit++;
}
#ifndef CLUSTER_RUN
#ifdef PRINT_TRACK_DEBUG
//Post-joined info.
track_it = tracks.begin();
std::cout << "----------CORRECTED TRACKS FOLLOW----------" << std::endl;
while ( track_it != tracks.end() )
{
std::cout << "Track ID " << track_it->second.GetTrackID() << "->Child of track ID " << track_it->second.GetParentID() << "\n";
for ( std::size_t stepcount = 0; stepcount < track_it->second.GetMCTrackStepCount(); stepcount++ )
{
std::cout << "\t Step " << stepcount << "->" << track_it->second.GetMCTrackStep(stepcount)->GetProcess() << "\n"
<< "\t\t X:" << track_it->second.GetMCTrackStep(stepcount)->GetEndpoint().X() << "\n"
<< "\t\t Y:" << track_it->second.GetMCTrackStep(stepcount)->GetEndpoint().Y() << "\n"
<< "\t\t Z:" << track_it->second.GetMCTrackStep(stepcount)->GetEndpoint().Z() << "\n"
<< "\t\t T:" << track_it->second.GetMCTrackStep(stepcount)->GetGlobalTime() << "\n"
<< "\t\t KE:" << track_it->second.GetMCTrackStep(stepcount)->GetKE() << std::endl;
}
//Remember to increment the iterator!
track_it++;
}
#endif
#endif
//Now the tracks that were split by reemissions etc have been rejoined. We
//are therefore free to do the analysis on them. Using the map iterator to
//jump through the tracks should be easiest and fastest
#ifndef PRINT_TRACK_DEBUG
//If the debug flag wasn't set, this iterator won't be in memory.
//So we declare it here.
IDtoTrackMap::iterator track_it;
#endif
std::cout << tracks.size() << " reconstructed tracks found." << std::endl;
track_it = tracks.begin();
//A counter so we can build in a progress indicator.
std::size_t track_index(1);
while ( track_it != tracks.end() )
{
#ifndef CLUSTER_RUN
std::cout << track_index << " of " << tracks.size() << " processed.\r" << std::flush;
#endif
//First set the proper event index for this photon.
thePhoton.fEventNo = eventIndex;
//tracks.front() object is the track we are working with! It is in no particular spatial or temporal
//order, but that is immaterial.
RAT::DS::MCTrack curTrack = track_it->second;
thePhoton.fParentID = curTrack.GetParentID();
//Set the birthplace for this track.
thePhoton.fBirthX = curTrack.GetMCTrackStep(0)->GetEndpoint().X();
thePhoton.fBirthY = curTrack.GetMCTrackStep(0)->GetEndpoint().Y();
thePhoton.fBirthZ = curTrack.GetMCTrackStep(0)->GetEndpoint().Z();
thePhoton.totalLength = curTrack.GetLength();
//Now check the trackID against the list of known hits.
if ( hit_list[curTrack.GetTrackID() - 1] == true ) thePhoton.MarkDefiniteHit();
//Boundary and process checking.
static std::string currentProcess("");
static bool LastStepEndedOnBoundary(false);
//Since this is the beginning, we can figure out what process generated this track.
std::string parentProcess = curTrack.GetMCTrackStep(0)->GetProcess();
if ( parentProcess == "Scintillation" ) thePhoton.isScintillation = true;
else if ( parentProcess == "Cerenkov" ) thePhoton.isCerenkov = true;
//Now onto the step checks.
for ( int step_index = 0; step_index < curTrack.GetMCTrackStepCount(); step_index++ )
{
//Get the current step and set the process variable.
RAT::DS::MCTrackStep curStep = *curTrack.GetMCTrackStep(step_index);
currentProcess = curStep.GetProcess();
//If the last step ended on a boundary...
if ( LastStepEndedOnBoundary && step_index != 0 )
{
//This will track the totally internally reflected photons.
//To actually capture the step that reflects, we need to get
//the last photon back!
if ( curStep.GetEndVolume() == curTrack.GetMCTrackStep(step_index-1)->GetVolume() )
{
RAT::DS::MCTrackStep temp_track_step = *curTrack.GetMCTrackStep(step_index-1);
thePhoton.AddReflection( temp_track_step.GetEndpoint().X(),
temp_track_step.GetEndpoint().Y(),
temp_track_step.GetEndpoint().Z(),
temp_track_step.GetGlobalTime() );
}
}
//This will check if the current step is involved in a process that can
//lead to a hit being recorded in the monte carlo. It is no guarantee that
//it is actually a hit (a definite hit), as that is determined probabilistically at
//(simulation) runtime. Therefore this is called an indefinite hit. Not all
//indefinite hits are definite hits, but all definite hits are indefinite hits.
if ( currentProcess.find("G4FastSimulationManagerProcess") != std::string::npos )
{
thePhoton.AddPMTHit( curStep.GetEndpoint().X(),
curStep.GetEndpoint().Y(),
curStep.GetEndpoint().Z(),
curStep.GetGlobalTime() );
}
//This is the process accounting step. If the photon was reemitted, mark it.
if ( currentProcess == "Reemission" )
{
//If we haven't already marked this photon as being reemitted, mark it.
if ( thePhoton.isReemitted == false ) thePhoton.isReemitted = true;
thePhoton.ReemissionCount++;
}
//If this step ended on a boundary, then the StepStatus will mark it as fGeomBoundary.
//During the next step, we can check if this flag was set, and if so, do reflection
//checking. If it didn't, but the flag is set from the previous step, unset it.
if ( curStep.GetStepStatus() == "GeomBoundary" ) LastStepEndedOnBoundary = true;
else if ( LastStepEndedOnBoundary ) LastStepEndedOnBoundary = false;
}
//We've done all of the necessary steps, so on to filling the tree and
//finishing the iteration.
theResultingTree->Fill();
thePhoton.Reset();
//To finish this iteration, just increment the map iterator and
//the track counter.
track_it++;
track_index++;
}
}
//Now just return the tree we built.
#ifndef CLUSTER_RUN
#endif
return theResultingTree;
}