Author: [log in to unmask]
Date: Sun Dec 18 15:18:10 2016
New Revision: 4640

Log:
Recalculate the track state at the Ecal and add the track states at SVT layer 1 and 2.

Modified:
    java/trunk/tracking/src/main/java/org/hps/recon/tracking/TrackTweakDriver.java

Modified: java/trunk/tracking/src/main/java/org/hps/recon/tracking/TrackTweakDriver.java
 =============================================================================
--- java/trunk/tracking/src/main/java/org/hps/recon/tracking/TrackTweakDriver.java	(original)
+++ java/trunk/tracking/src/main/java/org/hps/recon/tracking/TrackTweakDriver.java	Sun Dec 18 15:18:10 2016
@@ -2,12 +2,16 @@
 
 import java.util.List;
 
+import org.lcsim.detector.converter.compact.subdetector.HpsTracker2;
+import org.lcsim.detector.converter.compact.subdetector.SvtStereoLayer;
+import org.lcsim.detector.tracker.silicon.HpsSiSensor;
 import org.lcsim.event.EventHeader;
 import org.lcsim.event.Track;
 import org.lcsim.event.TrackState;
 import org.lcsim.event.base.BaseTrack;
 import org.lcsim.fit.helicaltrack.HelicalTrackFit;
 import org.lcsim.geometry.Detector;
+import org.lcsim.geometry.FieldMap;
 import org.lcsim.util.Driver;
 
 /**
@@ -18,18 +22,56 @@
  */
 public final class TrackTweakDriver extends Driver {
 
+    /** 
+     * Name of the constant denoting the position of the Ecal face in the 
+     * compact description.
+     */
+    private static final String ECAL_POSITION_CONSTANT_NAME = "ecal_dface";
+
+    /** Name of the SVT subdetector volume. */
+    private static final String SUBDETECTOR_NAME = "Tracker";
+   
+    /** Layer 1 track state index. */
+    private static final int LAYER1_TS_INDEX = 6;
+
+    /** Layer 2 track state index. */
+    private static final int LAYER2_TS_INDEX = 7;
+    
+    /** The B field map */
+    FieldMap bFieldMap = null;
+    
     /** The magnitude of the B field used.  */
     private double bField = 0.24; // Tesla
     
+    /** Position along the beamline of the Ecal face */
+    private double ecalPosition = 0; // mm
+   
+    /** Z position to start extrapolation from */
+    private double extStartPos = 700; // mm
+
+    /** The extrapolation step size */ 
+    private double stepSize = 5.0; // mm
+    
+    /** Top SVT layer 1 z position */
+    private double topLayer1Z = 0;
+    
+    /** Bot SVT layer 1 z position */
+    private double botLayer1Z = 0;
+
+    /** Top SVT layer 2 z position */
+    private double topLayer2Z = 0;
+    
+    /** Bot SVT layer 2 z position */
+    private double botLayer2Z = 0;
+    
     /** Name of the collection of tracks to apply corrections to. */
     private String trackCollectionName = "GBLTracks";
-   
+
     /** 
      * The track parameter corrections that will be applied to all top 
      * tracks. 
      */
     private double[] topTrackCorrection = {0, 0, 0, 0, 0};
-
     
     /** 
      * The track parameter corrections that will be applied to all bottom 
@@ -39,7 +81,7 @@
    
     /** List of collections to remove from an event. */
     private String[] removeCollections = {};
-    
+   
     /** Default constructor */
     public TrackTweakDriver() {}
    
@@ -113,9 +155,43 @@
    
     @Override
     protected void detectorChanged(Detector detector) {
-       
-        /** Get the B-field from the geometry description */
+      
+        // Get the field map from the detector object
+        bFieldMap = detector.getFieldMap(); 
+        
+        // Get the B-field from the geometry description 
         bField = TrackUtils.getBField(detector).magnitude();
+        
+        // Get the position of the Ecal from the compact description
+        ecalPosition = detector.getConstants().get(ECAL_POSITION_CONSTANT_NAME).getValue();
+    
+        // Get the stereo layers from the geometry and build the stereo
+        // layer maps
+        List<SvtStereoLayer> stereoLayers 
+            = ((HpsTracker2) detector.getSubdetector(SUBDETECTOR_NAME).getDetectorElement()).getStereoPairs();
+
+        // Loop through all of the stereo layers and find the midpoint between
+        // the sensors of layers 1 & 2.  This will be used to set the track 
+        // states at those layers.
+        for (SvtStereoLayer stereoLayer : stereoLayers) { 
+            System.out.println("Layer: " + stereoLayer.getLayerNumber());
+            if (stereoLayer.getLayerNumber() > 2) continue;
+            
+            HpsSiSensor axialSensor = stereoLayer.getAxialSensor();
+            HpsSiSensor stereoSensor = stereoLayer.getStereoSensor();
+            
+            double axialZ = axialSensor.getGeometry().getPosition().z();
+            double stereoZ = stereoSensor.getGeometry().getPosition().z(); 
+            double z = (axialZ + stereoZ)/2;
+            
+            if (stereoLayer.getLayerNumber() == 1) {
+                if (axialSensor.isTopLayer()) topLayer1Z = z; 
+                else botLayer1Z = z;
+            } else if(stereoLayer.getLayerNumber() == 2) {
+                if (axialSensor.isTopLayer()) topLayer2Z = z; 
+                else botLayer2Z = z;
+            }
+        }
     }
     
     @Override
@@ -123,7 +199,7 @@
     
         // If the event doesn't have the specified collection of tracks, throw
         // an exception.
-        if(!event.hasCollection(Track.class, trackCollectionName)) {
+        if (!event.hasCollection(Track.class, trackCollectionName)) {
             throw new RuntimeException("Track collection " + trackCollectionName + " doesn't exist");
         }
         
@@ -145,8 +221,30 @@
            }
            // Override the old track parameters with the tweaked parameters
            ((BaseTrack) track).setTrackParameters(tweakedTrackParameters, bField);
-        }
-       
+        
+           // Extrapolate the tweaked track to the face of the Ecal and get the
+           // track state
+           TrackState stateIP = TrackUtils.getTrackStateAtLocation(track, TrackState.AtIP);
+           if (stateIP == null) { 
+               throw new RuntimeException("IP track state for GBL track was not found");
+           }
+           TrackState stateEcalIP = TrackUtils.extrapolateTrackUsingFieldMap(stateIP, extStartPos, ecalPosition, stepSize, bFieldMap);
+           
+           // Replace the existing track state at the Ecal
+           int ecalTrackStateIndex = track.getTrackStates().indexOf(TrackUtils.getTrackStateAtLocation(track, TrackState.AtCalorimeter));
+           track.getTrackStates().set(ecalTrackStateIndex, stateEcalIP);
+            
+           // Get the track state at the first layer
+           double layer1Z = trackState.getTanLambda() > 0 ? topLayer1Z : botLayer1Z; 
+           TrackState stateLayer1 = TrackUtils.extrapolateTrackUsingFieldMap(stateIP, extStartPos, layer1Z, stepSize, bFieldMap);
+           track.getTrackStates().add(stateLayer1);
+
+           // Get the track state at the first layer
+           double layer2Z = trackState.getTanLambda() > 0 ? topLayer2Z : botLayer2Z; 
+           TrackState stateLayer2 = TrackUtils.extrapolateTrackUsingFieldMap(stateIP, extStartPos, layer2Z, stepSize, bFieldMap);
+           track.getTrackStates().add(stateLayer2);
+        }
+    
         for (String collection : removeCollections) { 
             event.remove(collection);
         }