lcsim/src/org/lcsim/recon/cluster/mipfinder
diff -u -r1.10 -r1.11
--- ShowerPointFinder.java 8 Mar 2010 19:35:53 -0000 1.10
+++ ShowerPointFinder.java 30 Jun 2010 16:59:36 -0000 1.11
@@ -1,6 +1,6 @@
package org.lcsim.recon.cluster.mipfinder;
-import java.util.*;
+import java.util.*;
import org.lcsim.event.*;
import hep.physics.vec.*;
@@ -10,219 +10,299 @@
import org.lcsim.recon.util.CalorimeterInformation;
import org.lcsim.geometry.Calorimeter.CalorimeterType;
- public class ShowerPointFinder{
+public class ShowerPointFinder
+{
+
protected HelixExtrapolator m_extrap;
- protected Map<Track,Cluster> m_tracksMatchedToClusters;
+ protected Map<Track, Cluster> m_tracksMatchedToClusters;
protected Set<CalorimeterHit> m_allhits;
protected int exam = 0; //to test neighbour hits
protected boolean debug = false;
protected boolean init;
protected CalorimeterInformation ci;
+ Set<Long> allHitIDs;
- public ShowerPointFinder(HelixExtrapolator extrap, Set<CalorimeterHit> allHits, Map<Track,Cluster> tracksMatchedToClusters ) {
- m_extrap = extrap;
- m_allhits = allHits;
- m_tracksMatchedToClusters = tracksMatchedToClusters;
- init = false;
+ public ShowerPointFinder(HelixExtrapolator extrap, Set<CalorimeterHit> allHits, Map<Track, Cluster> tracksMatchedToClusters)
+ {
+ m_extrap = extrap;
+ m_allhits = allHits;
+ m_tracksMatchedToClusters = tracksMatchedToClusters;
+ init = false;
+ allHitIDs = new HashSet<Long>();
+ for (CalorimeterHit allhit : m_allhits)
+ {
+ allHitIDs.add(allhit.getCellID());
+ }
}
-
- public Map<Track, BasicCluster> findMips() {
- if(!init)
+ public Map<Track, BasicCluster> findMips()
+ {
+ if (!init)
{
ci = CalorimeterInformation.instance();
init = true;
}
- Map<Track, BasicCluster> MapTrkToMIP = new HashMap<Track, BasicCluster>();
- for(Track tr : m_tracksMatchedToClusters.keySet()){
+ Map<Track, BasicCluster> MapTrkToMIP = new HashMap<Track, BasicCluster>();
+ for (Track tr : m_tracksMatchedToClusters.keySet())
+ {
BasicCluster mipclus = new BasicCluster(); //for new mip cluster
- HelixExtrapolationResult result = m_extrap.performExtrapolation(tr);
- Hep3Vector interceptPoint = null; // for debugging
- if (result != null) {
- interceptPoint = result.getInterceptPoint();
- }
- Cluster seed = m_tracksMatchedToClusters.get(tr);
-
- if(debug){
- Hep3Vector v = new BasicHep3Vector(tr.getMomentum());
- System.out.println("Given track");
- System.out.println("Debug: trk momentum= " + v.magnitude());
- if(interceptPoint != null) System.out.println("Debug: extra trk: pos= " + interceptPoint.magnitude() + " ("+ interceptPoint.x() + " " + interceptPoint.y() + " " + interceptPoint.z() + ")" );
- }
-
- //It might be needed to use intecept point instead of using first hit of seed
- //so that we can find the exact first hit corresponding to track
-
- // first hit of seed
- mipclus.addHit(seed.getCalorimeterHits().get(0));
- //test for neighbour hits
- examPosition(seed.getCalorimeterHits().get(0));
-
- int lastIterationWithFoundHit = -1;
- int maxSkippedLayers = 3;
- for( int iIteration = 0 ; iIteration < 70 ; iIteration++){ // 70~layers ECAL+HCAL until finding shower starting point
- // Get the information from last hit
- CalorimeterHit hit = mipclus.getCalorimeterHits().get( mipclus.getCalorimeterHits().size()-1);
- IDDecoder id = hit.getIDDecoder();
- id.setID(hit.getCellID());
- double x = id.getPosition()[0];
- double y = id.getPosition()[1];
- double z = id.getPosition()[2];
- double p = Math.sqrt(x*x+y*y+z*z);
- double r = Math.sqrt(x*x+y*y);
- double lastlayer = id.getVLayer();
- String lastsubdetName = hit.getSubdetector().getName();
- // Check for neighbouring hits in a 5x5x(2n+1) grid
- // where n is the number of iterations since we last saw a hit.
- // For example, if we saw a hit in the previous layer/iteration
- // it'll be a 5x5x3 grid.
- Set<Long> nearIDs = new HashSet<Long>();
- int countIterationsSinceLastHit = (iIteration - lastIterationWithFoundHit);
- if (countIterationsSinceLastHit <= 0) { throw new AssertionError("Book-keeping error"); }
- if (countIterationsSinceLastHit > maxSkippedLayers+1) { throw new AssertionError("Book-keeping error"); }
- long[] nearbyHitArray = id.getNeighbourIDs(countIterationsSinceLastHit, 2, 2);
- for (long lastnearID : nearbyHitArray ) { nearIDs.add(lastnearID); }
-
- Hep3Vector last0 = hitPosition(hit);
- Hep3Vector last1 = new BasicHep3Vector();
- if( mipclus.getCalorimeterHits().size() > 1){
- CalorimeterHit hit1 = mipclus.getCalorimeterHits().get( mipclus.getCalorimeterHits().size()-2);
- last1 = hitPosition(hit1);
- }
-
- //Search current hit in current layer and arrange in angular order
- SortedMap<Double, CalorimeterHit> sortedHitbyPosInside = new TreeMap();
- SortedMap<Double, CalorimeterHit> sortedHitbyPosCrossing = new TreeMap();
- SortedMap<Double, CalorimeterHit> sortedHitbyPos= new TreeMap();
- for (CalorimeterHit curhit : m_allhits){
- IDDecoder curid = curhit.getIDDecoder();
- curid.setID(curhit.getCellID());
- double curx = curid.getPosition()[0];
- double cury = curid.getPosition()[1];
- double curz = curid.getPosition()[2];
- double curp = Math.sqrt(curx*curx+cury*cury+curz*curz);
- double curr = Math.sqrt(curx*curx+cury*cury);
- Hep3Vector curpos = new BasicHep3Vector(curx,cury,curz);
- double curlayer = curid.getVLayer();
- String cursubdetName = curhit.getSubdetector().getName();
- //use geometric information and layer number to find cur hit
- // Inside Sub detector -> 0)
- // ECal Barrel -> 1) HCal Barrel or 2) HCal Endcap
- // ECal Endcap -> 3) HCal Endcap or 4) Ecal Barrel
- // HCal Endcap -> 5) HCal Barrel
- boolean InSide = (curlayer > lastlayer) && cursubdetName.contains(lastsubdetName) && nearIDs.contains(curhit.getCellID()); // 0)
- boolean EcalToHcalBarrel= (curid.getVLayer()==0 && cursubdetName.contains(ci.getName(CalorimeterType.HAD_BARREL))) && lastsubdetName.contains(ci.getName(CalorimeterType.EM_BARREL)); // 1) ECal Barrel -> HCal Barrel
- boolean BarrelEcalToEndHcal = (curid.getVLayer()==0 && cursubdetName.contains(ci.getName(CalorimeterType.HAD_ENDCAP))) && lastsubdetName.contains(ci.getName(CalorimeterType.EM_BARREL)); //2) ECal Barrel -> HCal Endcap (There is no way to HCal Barrel directly from ECal Endcap
- boolean EcalToHcalEndcap= (curid.getVLayer()==0 && cursubdetName.contains(ci.getName(CalorimeterType.HAD_ENDCAP))) && lastsubdetName.contains(ci.getName(CalorimeterType.EM_ENDCAP)); // 3) ECal Endcap -> HCal Endcap
- boolean EndToBarrelEcal = (curid.getVLayer()==0 && cursubdetName.contains(ci.getName(CalorimeterType.EM_BARREL))) && lastsubdetName.contains(ci.getName(CalorimeterType.EM_ENDCAP)); // 4) ECal Endcap -> ECal Barrel
- boolean EndToBarrelHcal = (curid.getVLayer()==0 && cursubdetName.contains(ci.getName(CalorimeterType.HAD_BARREL))) && lastsubdetName.contains(ci.getName(CalorimeterType.HAD_ENDCAP)); // 5) HCal Endcap -> HCal Barrel
-
- if(InSide || EcalToHcalBarrel || BarrelEcalToEndHcal || EcalToHcalEndcap || EndToBarrelEcal || EndToBarrelHcal){
- Hep3Vector cur = VecOp.sub(curpos, last0);
- Hep3Vector curUnit = VecOp.unit(cur);
- Hep3Vector last = null;
- if (mipclus.getCalorimeterHits().size() > 1) {
- last = VecOp.sub(last0, last1);
- } else {
- //Since there is only one hit we have at first, we use a extrapolated tangent vector
- if (result != null) {
- last = result.getTangent();
- }
- if (last == null) {
- // No extrapolation info and only one hit -- fall back to using
- // a straight line from the origin.
- last = VecOp.sub(last0, new BasicHep3Vector(0,0,0));
- }
- }
- Hep3Vector lastUnit = VecOp.unit(last);
- double a = Math.acos(VecOp.dot(lastUnit, curUnit));
- double d = VecOp.sub(cur,last).magnitude();
- if(a < 1.05 && d < 100){ //next hit in the range of angle 60 degree and less than 100mm
- if (InSide){
- sortedHitbyPosInside.put(a, curhit);
- }else{
- sortedHitbyPosCrossing.put(a, curhit);
- }
- }
- }
-
- }
- if (sortedHitbyPosInside.size() ==0 )
- sortedHitbyPos = sortedHitbyPosCrossing;
- else
- sortedHitbyPos = sortedHitbyPosInside;
-
- if(sortedHitbyPos.size() == 0) {
- // No hit found in this layer.
- if (countIterationsSinceLastHit <= maxSkippedLayers) {
- continue; // go to next layer
- } else {
- break; // stop -- ran out of hits and haven't seen any for several iterations
- }
- } else {
- // Found one or more hits
- lastIterationWithFoundHit = iIteration;
- }
- CalorimeterHit hitAdd = sortedHitbyPos.get(sortedHitbyPos.firstKey()); //add the hit with a smallest angle
- examPosition(hitAdd);
- mipclus.addHit(hitAdd);
-
- if (exam > 2) {
- if(debug) System.out.println("Debug: showering has already started " + exam + " layers ago" );
- double numRemove = 0;
- if(mipclus.getCalorimeterHits().size() < 4) {
- numRemove = mipclus.getCalorimeterHits().size() - 1 ;
- } else numRemove = 3;
- for(int k=0; k < numRemove ; k++) {
- CalorimeterHit toRemove = mipclus.getCalorimeterHits().get(mipclus.getCalorimeterHits().size()-1);
- mipclus.removeHit(toRemove);
- }
- break;
- }
- } //layer loop after mip
-
- if(debug){
- int k=0;
- if(mipclus.getCalorimeterHits().size() < 4) k = mipclus.getCalorimeterHits().size();
- else k = 4;
- for(int i =0; i < k ;i++){
- CalorimeterHit hit = mipclus.getCalorimeterHits().get( mipclus.getCalorimeterHits().size()-1-i);
- Hep3Vector v = hitPosition(hit);
- System.out.println("Debug: last "+i+" pos= "+v.magnitude()+" (" +v.x() + " " + v.y() + " " + v.z()+ ")" );
- }
- System.out.println("MIP hit size= " + mipclus.getCalorimeterHits().size());
- }
- MapTrkToMIP.put(tr, mipclus);
- } //track loop
+ HelixExtrapolationResult result = m_extrap.performExtrapolation(tr);
+ Cluster seed = m_tracksMatchedToClusters.get(tr);
+
+ // first hit of seed
+ mipclus.addHit(seed.getCalorimeterHits().get(0));
+ CalorimeterType lcalt = null;
+ boolean foundip = false;
+ boolean biggap = false;
+ // Start with the calorimeter of the seed. Follow as far as possible, then
+ // Look for transition to another calorimeter. Could possibly travel through
+ // all 4 calorimeters.
+ for (int ical = 0; ical < 4; ical++)
+ {
+ if(foundip)break;
+ //test the seed for neighbour hits
+ examPosition(mipclus.getCalorimeterHits().get(mipclus.getCalorimeterHits().size() - 1));
+
+ int lastIterationWithFoundHit = -1;
+ int maxSkippedLayers = 3;
+ CalorimeterType calt = ((Calorimeter) mipclus.getCalorimeterHits().get(mipclus.getCalorimeterHits().size() - 1).getSubdetector()).getCalorimeterType();
+ // If we finished a calorimeter and found no transition to another,
+ // we're done.
+ if (calt == lcalt)break;
+ lcalt = calt;
+ double cellsize = 3.5;
+ if((calt == CalorimeterType.HAD_BARREL)||(calt == CalorimeterType.HAD_ENDCAP))cellsize = 10.;
+ // First find all passing hits in initial subdetector
+ for (int iIteration = 0; iIteration < ci.getNLayers(calt); iIteration++)
+ {
+ // Get the information from last hit
+ CalorimeterHit hit = mipclus.getCalorimeterHits().get(mipclus.getCalorimeterHits().size() - 1);
+ IDDecoder id = hit.getIDDecoder();
+ id.setID(hit.getCellID());
+ double lastlayer = id.getVLayer();
+ String lastsubdetName = hit.getSubdetector().getName();
+ // Check for neighbouring hits in a 5x5x(2n+1) grid
+ // where n is the number of iterations since we last saw a hit.
+ // For example, if we saw a hit in the previous layer/iteration
+ // it'll be a 5x5x3 grid.
+ Set<Long> nearIDs = new HashSet<Long>();
+ int countIterationsSinceLastHit = (iIteration - lastIterationWithFoundHit);
+ if (countIterationsSinceLastHit <= 0)throw new AssertionError("Book-keeping error");
+ if (countIterationsSinceLastHit > maxSkippedLayers + 1)throw new AssertionError("Book-keeping error");
+ long[] nearbyHitArray = id.getNeighbourIDs(countIterationsSinceLastHit, 2, 2);
+ for (long lastnearID : nearbyHitArray)
+ {
+ nearIDs.add(lastnearID);
+ }
+
+ Hep3Vector last0 = hitPosition(hit);
+ Hep3Vector last1 = null;
+ if (mipclus.getCalorimeterHits().size() > maxSkippedLayers)
+ {
+ CalorimeterHit hit1 = mipclus.getCalorimeterHits().get(mipclus.getCalorimeterHits().size() - maxSkippedLayers - 1);
+ last1 = hitPosition(hit1);
+ }
+
+ // Initialize Map sorted by angle.
+ SortedMap<Double, CalorimeterHit> sortedHitbyPosInside = new TreeMap();
+ SortedMap<Double, CalorimeterHit> sortedHitbyPos = new TreeMap();
+ // Loop over all the hits. Should probably divide hits into subdetectors, since
+ // we're only looking at 1 at a time here.
+ for (CalorimeterHit curhit : m_allhits)
+ {
+ // Skip hits not in the subdetector of interest.
+ if (!curhit.getSubdetector().getName().contains(lastsubdetName))continue;
+ IDDecoder curid = curhit.getIDDecoder();
+ curid.setID(curhit.getCellID());
+ Hep3Vector curpos = new BasicHep3Vector(curid.getPosition());
+ double curlayer = curid.getVLayer();
+ // Only consder hits with increasing radius that are neighbors
+ if ((curlayer > lastlayer) && (nearIDs.contains(curhit.getCellID())))
+ {
+ Hep3Vector cur = VecOp.sub(curpos, last0);
+ Hep3Vector curUnit = VecOp.unit(cur);
+ Hep3Vector last = null;
+ if (last1 != null)
+ {
+ last = VecOp.sub(last0, last1);
+ }
+ else
+ {
+ //Since there is only one hit we have at first, we use a extrapolated tangent vector
+ if (result != null)
+ {
+ last = result.getTangent();
+ }
+ if (last == null)
+ {
+ // No extrapolation info and only one hit -- fall back to using
+ // a straight line from the origin.
+ last = VecOp.sub(last0, new BasicHep3Vector(0, 0, 0));
+ }
+ }
+ Hep3Vector lastUnit = VecOp.unit(last);
+ double ct = VecOp.dot(lastUnit, curUnit);
+ double st = Math.sqrt(1. - ct*ct);
+ double d = cur.magnitude()*st;
+ if (ct > 0.5 && d < 3.*cellsize)
+ {
+ sortedHitbyPosInside.put(1. - ct, curhit);
+ }
+ }
+
+ }
+ sortedHitbyPos = sortedHitbyPosInside;
+
+ if (sortedHitbyPos.size() == 0)
+ {
+ // No hit found in this layer.
+ if (countIterationsSinceLastHit <= maxSkippedLayers)
+ {
+ continue; // go to next layer
+ }
+ else
+ {
+ biggap = true;
+ break;
+ } // stop -- ran out of hits and haven't seen any for several iterations
+ }
+ else
+ {
+ // Found one or more hits
+ lastIterationWithFoundHit = iIteration;
+ }
+ CalorimeterHit hitAdd = sortedHitbyPos.get(sortedHitbyPos.firstKey()); //add the hit with a smallest angle
+ examPosition(hitAdd);
+ mipclus.addHit(hitAdd);
+
+ if (exam > 2)
+ {
+ double numRemove = 0;
+ if (mipclus.getCalorimeterHits().size() < 4)
+ {
+ numRemove = mipclus.getCalorimeterHits().size() - 1;
+ }
+ else
+ {
+ numRemove = 3;
+ }
+ for (int k = 0; k < numRemove; k++)
+ {
+ CalorimeterHit toRemove = mipclus.getCalorimeterHits().get(mipclus.getCalorimeterHits().size() - 1);
+ mipclus.removeHit(toRemove);
+ }
+ foundip = true;
+ break;
+ }
+ } //layer loop after mip
+ //Went as far as we could in 1 calorimeter, now check for crossovers
+ if(foundip)break;
+ CalorimeterHit hit = mipclus.getCalorimeterHits().get(mipclus.getCalorimeterHits().size() - 1);
+ String lastsubdetName = hit.getSubdetector().getName();
+ Hep3Vector last0 = hitPosition(hit);
+ Hep3Vector last1 = null;
+ if (mipclus.getCalorimeterHits().size() > maxSkippedLayers)
+ {
+ CalorimeterHit hit1 = mipclus.getCalorimeterHits().get(mipclus.getCalorimeterHits().size() - maxSkippedLayers - 1);
+ last1 = hitPosition(hit1);
+ }
+ SortedMap<Double, CalorimeterHit> sortedHitbyPosCrossing = new TreeMap();
+ for (CalorimeterHit curhit : m_allhits)
+ {
+ if (curhit.getSubdetector().getName().contains(lastsubdetName))
+ {
+ continue;
+ }
+ IDDecoder curid = curhit.getIDDecoder();
+ curid.setID(curhit.getCellID());
+ Hep3Vector curpos = new BasicHep3Vector(curid.getPosition());
+ String cursubdetName = curhit.getSubdetector().getName();
+ boolean EcalToHcalBarrel = (curid.getVLayer() == 0 && cursubdetName.contains(ci.getName(CalorimeterType.HAD_BARREL))) && lastsubdetName.contains(ci.getName(CalorimeterType.EM_BARREL)); // 1) ECal Barrel -> HCal Barrel
+ boolean BarrelEcalToEndHcal = (curid.getVLayer() == 0 && cursubdetName.contains(ci.getName(CalorimeterType.HAD_ENDCAP))) && lastsubdetName.contains(ci.getName(CalorimeterType.EM_BARREL)); //2) ECal Barrel -> HCal Endcap (There is no way to HCal Barrel directly from ECal Endcap
+ boolean EcalToHcalEndcap = (curid.getVLayer() == 0 && cursubdetName.contains(ci.getName(CalorimeterType.HAD_ENDCAP))) && lastsubdetName.contains(ci.getName(CalorimeterType.EM_ENDCAP)); // 3) ECal Endcap -> HCal Endcap
+ boolean EndToBarrelEcal = (curid.getVLayer() == 0 && cursubdetName.contains(ci.getName(CalorimeterType.EM_BARREL))) && lastsubdetName.contains(ci.getName(CalorimeterType.EM_ENDCAP)); // 4) ECal Endcap -> ECal Barrel
+ boolean EndToBarrelHcal = (curid.getVLayer() == 0 && cursubdetName.contains(ci.getName(CalorimeterType.HAD_BARREL))) && lastsubdetName.contains(ci.getName(CalorimeterType.HAD_ENDCAP)); // 5) HCal Endcap -> HCal Barrel
+
+ if (EcalToHcalBarrel || BarrelEcalToEndHcal || EcalToHcalEndcap || EndToBarrelEcal || EndToBarrelHcal)
+ {
+ if( (biggap)&& (EcalToHcalBarrel||EcalToHcalEndcap))continue;
+ calt = ((Calorimeter) curhit.getSubdetector()).getCalorimeterType();
+ cellsize = 3.5;
+ if((calt == CalorimeterType.HAD_BARREL)||(calt == CalorimeterType.HAD_ENDCAP))cellsize = 10.;
+ Hep3Vector cur = VecOp.sub(curpos, last0);
+ Hep3Vector curUnit = VecOp.unit(cur);
+ Hep3Vector last = null;
+ if (last1 != null)
+ {
+ last = VecOp.sub(last0, last1);
+ } else
+ {
+ //Since there is only one hit we have at first, we use a extrapolated tangent vector
+ if (result != null)
+ {
+ last = result.getTangent();
+ }
+ if (last == null)
+ {
+ // No extrapolation info and only one hit -- fall back to using
+ // a straight line from the origin.
+ last = VecOp.sub(last0, new BasicHep3Vector(0, 0, 0));
+ }
+ }
+ Hep3Vector lastUnit = VecOp.unit(last);
+ double ct = VecOp.dot(lastUnit, curUnit);
+ double st = Math.sqrt(1. - ct*ct);
+ double d = cur.magnitude()*st;
+ if (ct > 0.5 && d < 3.*cellsize && cur.magnitude() < 100.)
+ {
+ sortedHitbyPosCrossing.put(1. - ct, curhit);
+ }
+ }
+ }
+ if (sortedHitbyPosCrossing.size() > 0)
+ {
+ CalorimeterHit hitAdd = sortedHitbyPosCrossing.get(sortedHitbyPosCrossing.firstKey()); //add the hit with a smallest angle
+ examPosition(hitAdd);
+ mipclus.addHit(hitAdd);
+ }
+ }
+
+ MapTrkToMIP.put(tr, mipclus);
+ } //track loop
- return MapTrkToMIP;
+ return MapTrkToMIP;
}
//examine neighbour hits
- protected void examPosition(CalorimeterHit hit){
- Set<Long> allHitIDs = new HashSet<Long>();
- for (CalorimeterHit allhit : m_allhits) allHitIDs.add(allhit.getCellID());
-
- IDDecoder id = hit.getIDDecoder();
- id.setID(hit.getCellID());
- int count[] = new int[4];
- for (int i =0 ; i < 4 ; i++){
- long[] neighbours = id.getNeighbourIDs(0,i+1,i+1);
- for(long neighbourID : neighbours)
- if (allHitIDs.contains(neighbourID)) count[i]++;
- }
- if ( count[2] >=1 ) exam++ ; // if number of neighbour hits in 5x5 is larger than 1, count 1
- else exam = 0; // if number of neighbour hits is 0, set to zero and start again from 0
-
- if(debug){
- Hep3Vector v = hitPosition(hit);
- int p = (int) (v.magnitude());
- System.out.println(" hit: pos=" + p + " , " + count[0] + " hits in 3x3, " + count[1] + " hits in 5x5 " + count[2] + " hits in 7x7 " + count[3] + " hits in 9x9 " + id.getLayer() + " layer of " + hit.getSubdetector().getName());
- }
+ protected void examPosition(CalorimeterHit hit)
+ {
+
+ IDDecoder id = hit.getIDDecoder();
+ id.setID(hit.getCellID());
+ int count[] = new int[4];
+ for (int i = 0; i < 4; i++)
+ {
+ long[] neighbours = id.getNeighbourIDs(0, i + 1, i + 1);
+ for (long neighbourID : neighbours)
+ {
+ if (allHitIDs.contains(neighbourID))
+ {
+ count[i]++;
+ }
+ }
+ }
+ if (count[2] >= 1)
+ {
+ exam++; // if number of neighbour hits in 5x5 is larger than 1, count 1
+ } else
+ {
+ exam = 0; // if number of neighbour hits is 0, set to zero and start again from 0
+ }
}
//give the vector of hit
- protected Hep3Vector hitPosition(CalorimeterHit hit){
+ protected Hep3Vector hitPosition(CalorimeterHit hit)
+ {
return new BasicHep3Vector(hit.getPosition());
}
}
