added javadocs for Tree superclass

src/regions/Tree.java

@@ -1,11 +1,40 @@
 package regions;
 
+/**
+ * This is a superclass for octrees, quadtrees, and any other spatial trees.<p>
+ * 
+ * concept credit to Don Meagher, who first named and described Octrees in his 1980 paper,
+ * "Octree Encoding: A New Technique for the Representation, Manipulation and Display of 
+ * Arbitrary 3-D Objects by Computer."<p>
+ * 
+ * The idea works like this:<p>
+ * 
+ * For some arbitrary shape, you first define the bounding box of the shape (or the 
+ * smallest box your shape will fit inside of). This box outlines the minimum and maximum 
+ * x, y, and z dimensions of the shape.<p>
+ * 
+ * Next, you divide this cube evenly into 8 sections (2 x 2 x 2) and determine which sections 
+ * your shape fills, which ones it leaves empty, and which ones your shape partially 
+ * intersects.<p>
+ * 
+ * Intersected cubes are divided again into 8 subsections, and the process repeats until you 
+ * have divided and subdivided your bounding box into <i>only</i> full (<tt>true</tt>) and
+ * empty (<tt>false</tt>) cubes<p>
+ * 
+ * Then, given any point in space, you can quickly determine whether the point is inside or 
+ * outside your shape by navigating the tree to reach the smallest cube your point is in.
+ * 
+ * @author Kevin Mathewson
+ *
+ */
 public abstract class Tree 
 {
+	/**
+	 * Tree node containing a boolean and an array of sub-nodes
+	 */
 	public static class Node
 	{
 		public boolean 	full;
-		public Node		parent;
 		public Node[] 	children;
 
 		public Node(boolean full)
@@ -23,8 +52,12 @@ public abstract class Tree
 	}
 	
 	
-	
+	/**
-	static class IntReference
+	 * Defines an object containing a single int field. Used by the <tt>parseBytes()</tt> 
+	 * method to track its current <tt>index</tt> in the byte array. <tt>Node parseBytes()</tt> 
+	 * is a nested, self-calling method, and <tt>index</tt> increments with each call.
+	 */
+	static final class IntReference
 	{
 		int ref;
 		
@@ -35,18 +68,51 @@ public abstract class Tree
 	}
 	
 	
-	
+	/**
+	 * An abstract method, implemented slightly differently by octrees and quadtrees because 
+	 * octrees have 8 branches per node and quadtrees only 4.<p>
+	 * 
+	 * Given a byte array, interprets each byte as four 2-bit values, where 00 = partially full,
+	 * 01 = empty (<tt>false</tt>) and 10 = full (<tt>true</tt>). Octree nodes use 2 bytes 
+	 * each, Quadtree nodes use 1 byte each. Assumes a depth-first arrangement.<p>
+	 * 
+	 * @param index			current position in the byte array
+	 * @param bytes 		byte array, presumably read from a binary file
+	 * @param parentByte 	the 2-bit value (00000010, 00000001 or 00000000)
+	 * @return 				a new Node
+	 */
 	abstract Node parseBytes(IntReference index, byte[] bytes, int parentByte);
 	
 	
-	
+	/**
+	 * A simplified public alias for the package-private abstract method 
+	 * <tt>Node parseBytes(IntReference index, byte[] bytes, int parentByte)</tt><p>
+	 * 
+	 * Given a byte array, interprets each byte as four 2-bit values, where 00 = partially full,
+	 * 01 = empty (<tt>false</tt>) and 10 = full (<tt>true</tt>). Octree nodes use 2 bytes 
+	 * each, Quadtree nodes use 1 byte each. Assumes a depth-first arrangement.<p>
+	 * 
+	 * @param startAtIndex	where in the byte[] array to begin
+	 * @param bytes			byte array, presumably read from a binary file
+	 * @return 				a new Node
+	 */
 	public Node parseBytes(int startAtIndex, byte[] bytes)
 	{
 		return parseBytes	(	new IntReference(startAtIndex), 	bytes, 0	);
 	}
 	
 	
-	
+	/**
+	 * A simplified public alias for the package-private abstract method 
+	 * <tt>Node parseBytes(IntReference index, byte[] bytes, int parentByte)</tt><p>
+	 * 
+	 * Given a byte array, interprets each byte as four 2-bit values, where 00 = partially full,
+	 * 01 = empty (<tt>false</tt>) and 10 = full (<tt>true</tt>). Octree nodes use 2 bytes 
+	 * each, Quadtree nodes use 1 byte each. Assumes a depth-first arrangement.<p>
+	 * 
+	 * @param bytes			byte array, presumably read from a binary file
+	 * @return 				a new Node
+	 */
 	public Node parseBytes(byte[] bytes)
 	{
 		return parseBytes	(	new IntReference(0), 				bytes, 0	);

src/regions/World.java

@@ -0,0 +1,6 @@
+package regions;
+
+public class World 
+{
+
+}