diff -N RawTrackerHitConverter.java
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ RawTrackerHitConverter.java	17 Apr 2012 23:28:37 -0000	1.1
@@ -0,0 +1,111 @@

+package org.lcsim.util.heprep;
+
+import hep.graphics.heprep.HepRepFactory;
+import hep.graphics.heprep.HepRepInstance;
+import hep.graphics.heprep.HepRepInstanceTree;
+import hep.graphics.heprep.HepRepType;
+import hep.graphics.heprep.HepRepTypeTree;
+import hep.physics.vec.Hep3Vector;
+
+import java.awt.Color;
+import java.util.Collection;
+import java.util.List;
+
+import org.lcsim.detector.DetectorElementStore;
+import org.lcsim.detector.IDetectorElement;
+import org.lcsim.detector.ITransform3D;
+import org.lcsim.detector.identifier.IExpandedIdentifier;
+import org.lcsim.detector.identifier.IIdentifier;
+import org.lcsim.detector.identifier.IIdentifierDictionary;
+import org.lcsim.detector.solids.LineSegment3D;
+import org.lcsim.detector.tracker.silicon.SiSensor;
+import org.lcsim.detector.tracker.silicon.SiSensorElectrodes;
+import org.lcsim.detector.tracker.silicon.SiStrips;
+import org.lcsim.event.EventHeader;
+import org.lcsim.event.EventHeader.LCMetaData;
+import org.lcsim.event.RawTrackerHit;
+
+/**
+ * Convert RawTrackerHit objects into HepRep line segments.
+ * @author Jeremy McCormick <[log in to unmask]>
+ * @version $Id: RawTrackerHitConverter.java,v 1.1 2012/04/17 23:28:37 jeremy Exp $
+ */
+class RawTrackerHitConverter implements HepRepCollectionConverter
+{
+   public boolean canHandle(Class k) {
+      return RawTrackerHit.class.isAssignableFrom(k);
+   }
+   
+   public void convert(EventHeader event, List collection, HepRepFactory factory, HepRepTypeTree typeTree, HepRepInstanceTree instanceTree) {      
+      LCMetaData meta = event.getMetaData(collection);
+      String name = meta.getName();           
+
+      HepRepType typeX = factory.createHepRepType(typeTree, name);
+      typeX.addAttValue("layer", LCSimHepRepConverter.HITS_LAYER);
+      typeX.addAttValue("drawAs", "Line");
+      typeX.addAttValue("color", Color.GREEN);
+      
+      // Setup links to SiSensor objects in detector geometry.
+      setSensors(meta, (List<RawTrackerHit>)collection);
+            
+      // Loop over hits and draw them as lines.
+      for (RawTrackerHit hit : (List<RawTrackerHit>)collection) {
+          try {
+              SiSensor sensor = (SiSensor)hit.getDetectorElement();
+              Collection<SiSensorElectrodes> trodes = sensor.getReadoutElectrodes();
+              SiStrips strips = (SiStrips)trodes.toArray()[0];
+              LineSegment3D line = strips.getStrip(hit.getIdentifierFieldValue("strip"));
+              ITransform3D transform = strips.getLocalToGlobal();
+              Hep3Vector startPoint = transform.transformed(line.getStartPoint());
+              Hep3Vector endPoint = transform.transformed(line.getEndPoint());
+              HepRepInstance instance = factory.createHepRepInstance(instanceTree, typeX);
+              factory.createHepRepPoint(instance, startPoint.x(), startPoint.y(), startPoint.z());
+              factory.createHepRepPoint(instance, endPoint.x(), endPoint.y(), endPoint.z());
+          }
+          catch (Exception e) {
+              e.printStackTrace();
+              continue;
+          }
+      }
+   }
+   
+   private void setSensors(LCMetaData meta, List<RawTrackerHit> hits) {
+
+       // Get the ID dictionary and field information.
+       IIdentifierDictionary dict = meta.getIDDecoder().getSubdetector().getDetectorElement().getIdentifierHelper().getIdentifierDictionary();
+       int fieldIdx = dict.getFieldIndex("side");
+       int sideIdx = dict.getFieldIndex("strip");
+       
+       for (RawTrackerHit hit : hits) {
+              
+           // The "side" and "strip" fields needs to be stripped from the ID for sensor lookup.
+           IExpandedIdentifier expId = dict.unpack(hit.getIdentifier());
+           expId.setValue(fieldIdx, 0);
+           expId.setValue(sideIdx, 0);
+           IIdentifier strippedId = dict.pack(expId);
+       
+           // Find the sensor DetectorElement.
+           List<IDetectorElement> des = DetectorElementStore.getInstance().find(strippedId);
+           if (des == null || des.size() == 0) {
+               throw new RuntimeException("Failed to find any DetectorElements with stripped ID <0x" + Long.toHexString(strippedId.getValue()) + ">.");
+           }
+           else if (des.size() == 1) {
+               hit.setDetectorElement((SiSensor)des.get(0));
+           }
+           else {
+               // Use first sensor found, which should work unless there are sensors with duplicate IDs.
+               for (IDetectorElement de : des) {
+                   if (de instanceof SiSensor) {
+                       hit.setDetectorElement((SiSensor)de);
+                       break;
+                   }
+               }
+           }   
+           
+           // No sensor was found.
+           if (hit.getDetectorElement() == null) {
+               throw new RuntimeException("No sensor was found for hit with stripped ID <0x" + Long.toHexString(strippedId.getValue()) + ">.");
+           }
+       }
+   }
+}