diff -u -r1.10 -r1.11
--- CalorimeterHit.java	23 May 2008 06:53:35 -0000	1.10
+++ CalorimeterHit.java	17 Mar 2009 22:45:44 -0000	1.11
@@ -1,17 +1,17 @@

 package org.lcsim.event;
 

-import org.lcsim.geometry.IDDecoder;
-import org.lcsim.geometry.Subdetector;

+import hep.physics.vec.Hep3Vector;

 
 /**
  * A hit in a calorimeter.
  * The super-interface gives access to subdetector, identifiers, iddecoder, etc.
  * @see org.lcsim.event.Hit
  * @author tonyj

- * @version $Id: CalorimeterHit.java,v 1.10 2008/05/23 06:53:35 jeremy Exp $

+ * @author Jeremy McCormick <[log in to unmask]>
+ * @version $Id: CalorimeterHit.java,v 1.11 2009/03/17 22:45:44 jeremy Exp $

  */
 public interface CalorimeterHit

-extends Hit

+extends HitWithPosition

 {
    /**
     * Raw energy deposited in calorimeter cell.

@@ -42,4 +42,4 @@

     * the hit position from the hit ID.
     */
    public double[] getPosition();

-}

+}

\ No newline at end of file

diff -u -r1.6 -r1.7
--- BaseCalorimeterHit.java	10 Sep 2008 21:24:41 -0000	1.6
+++ BaseCalorimeterHit.java	17 Mar 2009 22:45:44 -0000	1.7
@@ -1,25 +1,29 @@

 package org.lcsim.event.base;
 

+import hep.physics.vec.Hep3Vector;
+

 import org.lcsim.detector.identifier.IIdentifier;

-import org.lcsim.detector.identifier.IIdentifierHelper;

 import org.lcsim.detector.identifier.Identifier;
 import org.lcsim.event.CalorimeterHit;
 import org.lcsim.event.util.SamplingFractionManager;
 import org.lcsim.geometry.IDDecoder;
 
 /**

+ * Base implementation of CalorimeterHit.

  * @author tonyj

+ * @author Jeremy McCormick <[log in to unmask]>

  */

-public abstract class BaseCalorimeterHit 
-extends BaseHit 
-implements CalorimeterHit 
-{       
-    protected double rawEnergy;
-    protected double corrEnergy = -1;

+public abstract class BaseCalorimeterHit extends BaseHitWithPosition implements CalorimeterHit 
+{   	
+    protected double rawEnergy;    
+    protected double corrEnergy = UNSET_CORRECTED_ENERGY;

     protected double[] position;

+    protected Hep3Vector positionVec;

     protected double time;
     protected long id;
     

+    private static final double UNSET_CORRECTED_ENERGY = -1;
+    

     public double getTime() 
     {
         return time;

@@ -41,7 +45,7 @@

 
     public double getCorrectedEnergy() 
     {

-        if (corrEnergy == -1)

+        if (corrEnergy == UNSET_CORRECTED_ENERGY)

         {
             calculateCorrectedEnergy();
         }

@@ -79,13 +83,8 @@

     
     public IIdentifier getIdentifier()
     {

-    	if (this.compactId == null)
-    		this.compactId = new Identifier(this.id);
-    	return this.compactId;
-    }
-    
-    public IIdentifierHelper getIdentifierHelper() 
-    {
-        return getSubdetector().getDetectorElement().getIdentifierHelper();

+    	if (compactId == null)
+    		compactId = new Identifier(id);
+    	return compactId;

     }
 }

\ No newline at end of file

diff -u -r1.5 -r1.6
--- BaseHit.java	20 Aug 2008 01:34:21 -0000	1.5
+++ BaseHit.java	17 Mar 2009 22:45:44 -0000	1.6
@@ -1,5 +1,7 @@

 package org.lcsim.event.base;
 

+import hep.physics.vec.Hep3Vector;
+

 import org.lcsim.detector.DetectorIdentifierHelper;
 import org.lcsim.detector.IDetectorElement;
 import org.lcsim.detector.identifier.IExpandedIdentifier;

@@ -10,6 +12,10 @@

 import org.lcsim.geometry.IDDecoder;
 import org.lcsim.geometry.Subdetector;
 

+/**
+ * A base class for hit-like objects.
+ * @author Jeremy McCormick <[log in to unmask]>
+ */

 public abstract class BaseHit
 implements Hit
 {

@@ -17,34 +23,68 @@

     protected IExpandedIdentifier expId;
     protected IIdentifier compactId;
     protected IDetectorElement de;

+    protected Hep3Vector positionVec;

+    /**
+     * Get the metadata associated with this hit.
+     * @return The hit's metadata.
+     */

     public LCMetaData getMetaData() 
     {
         return meta;
     }
 

+    /**
+     * Set the metadata associated with this hit.
+     * By default, this will not override an
+     * existing value.     
+     */

     public void setMetaData(LCMetaData meta) 
     {

-        // Don't allow meta to be reset!  
-    	// Override in subclass if you want to enable this.
-    	if (this.meta == null) this.meta = meta;

+    	if (this.meta == null)
+    	{
+    		this.meta = meta;
+    	}

     }
 	

+    /**
+     * Get the subdetector that this hit belongs to.
+     * @return The Subdetector of this hit.
+     */

     public Subdetector getSubdetector() 
     {
         return getIDDecoder().getSubdetector();
     }
 

+    /**
+     * Get the deepest {@see org.lcsim.detector.IDetectorElement} associated with this hit.
+     * If this is not set manually using {@see #setDetectorElement(IDetectorElement)}
+     * then the subdetector's DetectorElement is searched using the hit's position
+     * from {@see #getPositionVec()}.
+ 	 * @return The IDetectorElement for this hit.
+     */

     public IDetectorElement getDetectorElement() 
     {
         return de;
     }

-	

+    	
+    /**
+     * Set the @see org.lcsim.detector.IDetectorElement of this hit.
+     * By default, this will not override an existing value.
+     */

     public void setDetectorElement(IDetectorElement de)
     {

-        this.de = de;

+    	if (this.de == null)
+    	{
+    		this.de = de;
+    	}

     }
 

+    /**
+     * Get the {@see org.lcsim.detector.identifier.IExpandedIdentifier}
+     * of this hit.
+     * @return The <code>IExpandedIdentifier</code> of this hit.
+     */

     public IExpandedIdentifier getExpandedIdentifier() 
     {
         if (expId == null) 

@@ -54,23 +94,39 @@

         return expId;
     }
 

+    /**
+     * Get the identifier of this hit.
+     * @return The identifier of this hit.
+     */

     public IIdentifier getIdentifier() 
     {
         return compactId;
     }
 

+    /**
+     * Get the identifier helper of this hit.
+     * @return The hit's identifier helper.
+     */

     public IIdentifierHelper getIdentifierHelper() 
     {

-        return getDetectorElement().getIdentifierHelper();

+        return getSubdetector().getDetectorElement().getIdentifierHelper();

     }
     

+    /**
+     * Get the detector identifier helper of this hit.
+     * @return The hit's detector identifier helper.
+     */

     public DetectorIdentifierHelper getDetectorIdentifierHelper()
     {

-    	return (DetectorIdentifierHelper)getSubdetector().getDetectorElement().getIdentifierHelper();

+    	return (DetectorIdentifierHelper)getIdentifierHelper();

     }
 

-    public IDDecoder getIDDecoder() 

+    /**
+     * Get the {@see org.lcsim.geometryIDDecoder} of this hit.
+     * @return The hit's id decoder.
+     */
+    public IDDecoder getIDDecoder()

     {
         return meta.getIDDecoder();
     }

-}

\ No newline at end of file

+}	

\ No newline at end of file