diff --git a/MapManager.java b/MapManager.java
index e5720003..0155dde9 100644
--- a/MapManager.java
+++ b/MapManager.java
@@ -52,6 +52,8 @@ public class MapManager extends Thread {
 
 	/* a list of MapTiles to be updated */
 	private LinkedList<MapTile> staleTiles;
+	/* a list of MapTiles for which the cave tile is to be updated */
+	private LinkedList<MapTile> staleCaveTiles;
 
 	/* whether the worker thread should be running now */
 	private boolean running = false;
@@ -84,6 +86,8 @@ public class MapManager extends Thread {
 
 	/* this list stores the tile updates */
 	public LinkedList<TileUpdate> tileUpdates = null;
+	/* this list stores the cave tile updates */
+	public LinkedList<TileUpdate> caveTileUpdates = null;
 
 	/* map debugging mode (send debugging messages to this player) */
 	public String debugPlayer = null;
@@ -138,7 +142,9 @@ public class MapManager extends Thread {
 
 		tileStore = new HashMap<Long, MapTile>();
 		staleTiles = new LinkedList<MapTile>();
+		staleCaveTiles = new LinkedList<MapTile>();
 		tileUpdates = new LinkedList<TileUpdate>();
+		caveTileUpdates = new LinkedList<TileUpdate>();
 		zoomCache = new Cache<String, BufferedImage>(zoomCacheSize);
 		
 		signs = new HashMap<String, Warp>();
@@ -254,37 +260,62 @@ public class MapManager extends Thread {
 		}
 	}
 
+	/* update tile update list */
+	private void updateUpdates(MapTile t, LinkedList<TileUpdate> lst)
+	{
+		long now = System.currentTimeMillis();
+		long deadline = now - maxTileAge;
+
+		synchronized(lock) {
+			ListIterator<TileUpdate> it = lst.listIterator(0);
+			while(it.hasNext()) {
+				TileUpdate tu = it.next();
+				if(tu.at < deadline || tu.tile == t)
+					it.remove();
+			}
+			lst.addLast(new TileUpdate(now, t));
+		}
+	}
+
 	/* the worker/renderer thread */
 	public void run()
 	{
 		log.info("Map renderer has started.");
 
 		while(running) {
+			boolean found = false;
+
 			MapTile t = this.popStaleTile();
 			if(t != null) {
 				t.render(this);
 
-				long now = System.currentTimeMillis();
-				long deadline = now - maxTileAge;
-
-				/* update the tileupdate list */
-				synchronized(lock) {
-					ListIterator<TileUpdate> it = tileUpdates.listIterator(0);
-					while(it.hasNext()) {
-						TileUpdate tu = it.next();
-						if(tu.at < deadline || tu.tile == t)
-							it.remove();
-					}
-					tileUpdates.addLast(new TileUpdate(now, t));
-				}
+				updateUpdates(t, tileUpdates);
 
 				try {
 					this.sleep(renderWait);
 				} catch(InterruptedException e) {
 				}
-			} else {
+
+				found = true;
+			}
+
+			MapTile ct = this.popStaleCaveTile();
+			if(ct != null) {
+				ct.renderCave(this);
+
+				updateUpdates(ct, caveTileUpdates);
+
 				try {
-					this.sleep(1000);
+					this.sleep(renderWait);
+				} catch(InterruptedException e) {
+				}
+
+				found = true;
+			}
+
+			if(!found) {
+				try {
+					this.sleep(500);
 				} catch(InterruptedException e) {
 				}
 			}
@@ -350,18 +381,47 @@ public class MapManager extends Thread {
 		}
 	}
 
+	/* get next MapTile for which the cave map needs to be
+	 * regenerated, or null
+	 * the mapTile is removed from the list of stale cave tiles */
+	public MapTile popStaleCaveTile()
+	{
+		synchronized(lock) {
+			try {
+				MapTile t = staleCaveTiles.removeFirst();
+				t.staleCave = false;
+				return t;
+			} catch(NoSuchElementException e) {
+				return null;
+			}
+		}
+	}
+
 	/* put a MapTile that needs to be regenerated on the list of stale tiles */
 	public boolean pushStaleTile(MapTile m)
 	{
 		synchronized(lock) {
-			if(m.stale) return false;
+			boolean ret = false;
 
-			m.stale = true;
-			staleTiles.addLast(m);
+			if(!m.stale) {
+				m.stale = true;
+				staleTiles.addLast(m);
 
-			debug(m.toString() + " is now stale");
+				debug(m.toString() + " is now stale");
 
-			return true;
+				ret = true;
+			}
+
+			if(!m.staleCave) {
+				m.staleCave = true;
+				staleCaveTiles.addLast(m);
+
+				debug(m.toString() + " cave is now stale");
+
+				ret = true;
+			}
+
+			return ret;
 		}
 	}
 
@@ -393,7 +453,7 @@ public class MapManager extends Thread {
 	public int getStaleCount()
 	{
 		synchronized(lock) {
-			return staleTiles.size();
+			return staleTiles.size() + staleCaveTiles.size();
 		}
 	}
 
@@ -401,7 +461,7 @@ public class MapManager extends Thread {
 	public int getRecentUpdateCount()
 	{
 		synchronized(lock) {
-			return tileUpdates.size();
+			return tileUpdates.size() + caveTileUpdates.size();
 		}
 	}
 
diff --git a/MapTile.java b/MapTile.java
index a7ca15e5..804edf2a 100644
--- a/MapTile.java
+++ b/MapTile.java
@@ -24,6 +24,9 @@ public class MapTile {
 	/* whether this tile needs to be updated */
 	boolean stale = false;
 
+	/* whether the cave map of this tile needs to be updated */
+	boolean staleCave = false;
+
 	/* create new MapTile */
 	public MapTile(int px, int py, int zpx, int zpy)
 	{
@@ -37,6 +40,57 @@ public class MapTile {
 		mz = MapManager.anchorz + px / 2 - py / 2;
 	}
 
+	/* try to get the server to load the relevant chunks */
+	public void loadChunks()
+	{
+		int x1 = mx - 64;
+		int x2 = mx + MapManager.tileWidth / 2 + MapManager.tileHeight / 2;
+
+		int z1 = mz - MapManager.tileHeight / 2;
+		int z2 = mz + MapManager.tileWidth / 2 + 64;
+
+		int x, z;
+		Server s = etc.getServer();
+
+		for(x=x1; x<x2; x+=16) {
+			for(z=z1; z<z2; z+=16) {
+				if(!s.isChunkLoaded(x, 0, z)) {
+					log.info("map render loading chunk: " + x + ", 0, " + z);
+
+					try {
+						s.loadChunk(x, 0, z);
+					} catch(Exception e) {
+						log.log(Level.SEVERE, "Caught exception from loadChunk!", e);
+					}
+				}
+			}
+		}
+	}
+
+	/* check if all relevant chunks are loaded */
+	public boolean isMapLoaded()
+	{
+		int x1 = mx - 64;
+		int x2 = mx + MapManager.tileWidth / 2 + MapManager.tileHeight / 2;
+
+		int z1 = mz - MapManager.tileHeight / 2;
+		int z2 = mz + MapManager.tileWidth / 2 + 64;
+
+		int x, z;
+		Server s = etc.getServer();
+
+		for(x=x1; x<x2; x+=16) {
+			for(z=z1; z<z2; z+=16) {
+				if(!s.isChunkLoaded(x, 0, z)) {
+					log.info("chunk not loaded: " + x + ", " + z + " for tile " + this.toString());
+					return false;
+				}
+			}
+		}
+
+		return true;
+	}
+
 	/* get key by projection position */
 	public static long key(int px, int py)
 	{
@@ -69,6 +123,10 @@ public class MapTile {
 	{
 		mgr.debug("Rendering tile: " + this.toString());
 
+		//loadChunks();
+		if(!isMapLoaded())
+			return;
+
 		BufferedImage im = new BufferedImage(MapManager.tileWidth, MapManager.tileHeight, BufferedImage.TYPE_INT_RGB);
 
 		WritableRaster r = im.getRaster();
@@ -118,45 +176,110 @@ public class MapTile {
 			iz --;
 		}
 
+		/* save the generated tile */
+		saveTile(getPath(mgr), im, getZoomPath(mgr), mgr);
+	}
+
+	/* render cave map for this tile */
+	public void renderCave(MapManager mgr)
+	{
+		mgr.debug("Rendering cave map: " + this.toString());
+
+		//loadChunks();
+		if(!isMapLoaded())
+			return;
+
+		BufferedImage im = new BufferedImage(MapManager.tileWidth, MapManager.tileHeight, BufferedImage.TYPE_INT_RGB);
+
+		WritableRaster r = im.getRaster();
+
+		int ix = mx;
+		int iy = my;
+		int iz = mz;
+		int jx, jz;
+
+		int x, y;
+
+		/* draw the map */
+		for(y=0; y<MapManager.tileHeight;) {
+			jx = ix;
+			jz = iz;
+
+			for(x=MapManager.tileWidth-1; x>=0; x-=2) {
+				Color c1 = caveScan(mgr, jx, iy, jz, 0);
+				Color c2 = caveScan(mgr, jx, iy, jz, 2);
+
+				r.setPixel(x, y, new int[] { c1.getRed(), c1.getGreen(), c1.getBlue() });
+				r.setPixel(x-1, y, new int[] { c2.getRed(), c2.getGreen(), c2.getBlue() });
+
+				jx++;
+				jz++;
+
+			}
+
+			y ++;
+
+			jx = ix;
+			jz = iz - 1;
+
+			for(x=MapManager.tileWidth-1; x>=0; x-=2) {
+				Color c1 = caveScan(mgr, jx, iy, jz, 2);
+				jx++;
+				jz++;
+				Color c2 = caveScan(mgr, jx, iy, jz, 0);
+
+				r.setPixel(x, y, new int[] { c1.getRed(), c1.getGreen(), c1.getBlue() });
+				r.setPixel(x-1, y, new int[] { c2.getRed(), c2.getGreen(), c2.getBlue() });
+			}
+
+			y ++;
+
+			ix ++;
+			iz --;
+		}
+
+		/* save the generated tile */
+		saveTile(getCavePath(mgr), im, getZoomCavePath(mgr), mgr);
+	}
+
+	/* save rendered tile, update zoom-out tile */
+	public void saveTile(String tilePath, BufferedImage im, String zoomPath, MapManager mgr)
+	{
 		/* save image */
 		try {
-			String path = getPath(mgr);
-			File file = new File(path);
+			File file = new File(tilePath);
 			ImageIO.write(im, "png", file);
 		} catch(IOException e) {
-			log.log(Level.SEVERE, "Failed to save tile: " + getPath(mgr), e);
+			log.log(Level.SEVERE, "Failed to save tile: " + tilePath, e);
 		} catch(java.lang.NullPointerException e) {
-			log.log(Level.SEVERE, "Failed to save tile (NullPointerException): " + getPath(mgr), e);
+			log.log(Level.SEVERE, "Failed to save tile (NullPointerException): " + tilePath, e);
 		}
 
 		/* now update zoom-out tile */
-		String zPath = getZoomPath(mgr);
-		BufferedImage zIm = mgr.zoomCache.get(zPath);
+		BufferedImage zIm = mgr.zoomCache.get(zoomPath);
 
 		if(zIm == null) {
 			/* zoom-out tile doesn't exist - try to load it from disk */
 
-			mgr.debug("Trying to load zoom-out tile: " + zPath);
+			mgr.debug("Trying to load zoom-out tile: " + zoomPath);
 
 			try {
-				File file = new File(zPath);
+				File file = new File(zoomPath);
 				zIm = ImageIO.read(file);
 			} catch(IOException e) {
 			}
 
-
 			if(zIm == null) {
-				mgr.debug("Failed to load zoom-out tile: " + zPath);
-
+				mgr.debug("Failed to load zoom-out tile: " + zoomPath);
 				/* create new one */
 				/* TODO: we might use existing tiles that we could load
 				 * to fill the zoomed out tile in... */
 				zIm = new BufferedImage(MapManager.tileWidth, MapManager.tileHeight, BufferedImage.TYPE_INT_RGB);
 			} else {
-				mgr.debug("Loaded zoom-out tile from " + zPath);
+				mgr.debug("Loaded zoom-out tile from " + zoomPath);
 			}
 		} else {
-			mgr.debug("Using zoom-out tile from cache: " + zPath);
+			mgr.debug("Using zoom-out tile from cache: " + zoomPath);
 		}
 
 		/* update zoom-out tile */
@@ -179,22 +302,22 @@ public class MapTile {
 		g2.drawImage(im, ox, oy, scw, sch, null);
 
 		/* update zoom-out tile cache */
-		BufferedImage oldIm = mgr.zoomCache.put(zPath, zIm);
+		BufferedImage oldIm = mgr.zoomCache.put(zoomPath, zIm);
 		if(oldIm != null && oldIm != zIm) {
 			oldIm.flush();
 		}
 
 		/* save zoom-out tile */
 		try {
-			File file = new File(zPath);
+			File file = new File(zoomPath);
 			ImageIO.write(zIm, "png", file);
-			mgr.debug("saved zoom-out tile at " + zPath);
+			mgr.debug("saved zoom-out tile at " + zoomPath);
 
 			//log.info("Saved tile: " + path);
 		} catch(IOException e) {
-			log.log(Level.SEVERE, "Failed to save zoom-out tile: " + zPath, e);
+			log.log(Level.SEVERE, "Failed to save zoom-out tile: " + zoomPath, e);
 		} catch(java.lang.NullPointerException e) {
-			log.log(Level.SEVERE, "Failed to save zoom-out tile (NullPointerException): " + zPath, e);
+			log.log(Level.SEVERE, "Failed to save zoom-out tile (NullPointerException): " + zoomPath, e);
 		}
 	}
 
@@ -210,6 +333,18 @@ public class MapTile {
 		return mgr.tilepath + "zt_" + zpx + "_" + zpy + ".png";
 	}
 
+	/* generate a path name for this cave map tile */
+	public String getCavePath(MapManager mgr)
+	{
+		return mgr.tilepath + "ct_" + px + "_" + py + ".png";
+	}
+
+	/* generate a path name for the zoomed-out cave tile */
+	public String getZoomCavePath(MapManager mgr)
+	{
+		return mgr.tilepath + "czt_" + zpx + "_" + zpy + ".png";
+	}
+
 	/* try to load already generated image */
 	public BufferedImage loadTile(MapManager mgr)
 	{
@@ -284,4 +419,87 @@ public class MapTile {
 			}
 		}
 	}
+
+	/* cast a ray into the caves */
+	private Color caveScan(MapManager mgr, int x, int y, int z, int seq)
+	{
+		Server s = etc.getServer();
+		boolean air = true;
+
+		for(;;) {
+			if(y < 0)
+				return Color.BLACK;
+
+			int id = s.getBlockIdAt(x, y, z);
+
+			switch(seq) {
+			case 0:
+				x--;
+				break;
+			case 1:
+				y--;
+				break;
+			case 2:
+				z++;
+				break;
+			case 3:
+				y--;
+				break;
+			}
+
+			seq = (seq + 1) & 3;
+
+			switch(id) {
+			case 20:
+			case 18:
+			case 17:
+			case 78:
+			case 79:
+				id = 0;
+				break;
+			default:
+			}
+
+			if(id != 0) {
+				air = false;
+				continue;
+			}
+
+			if(id == 0 && !air) {
+				int cr, cg, cb;
+				int mult = 256;
+
+				if(y < 64) {
+					cr = 0;
+					cg = 64 + y * 3;
+					cb = 255 - y * 4;
+				} else {
+					cr = (y-64) * 4;
+					cg = 255;
+					cb = 0;
+				}
+
+				switch(seq) {
+				case 0:
+					mult = 224;
+					break;
+				case 1:
+					mult = 256;
+					break;
+				case 2:
+					mult = 192;
+					break;
+				case 3:
+					mult = 160;
+					break;
+				}
+
+				cr = cr * mult / 256;
+				cg = cg * mult / 256;
+				cb = cb * mult / 256;
+
+				return new Color(cr, cg, cb);
+			}
+		}
+	}
 }
diff --git a/WebServerRequest.java b/WebServerRequest.java
index bcf2f6d5..61ba8bad 100644
--- a/WebServerRequest.java
+++ b/WebServerRequest.java
@@ -60,6 +60,7 @@ public class WebServerRequest extends Thread {
 
 			int current = (int) (System.currentTimeMillis() / 1000);
 			long cutoff = 0;
+
 			if(path.charAt(0) == '/') {
 				try {
 					cutoff = ((long) Integer.parseInt(path.substring(1))) * 1000;
@@ -114,7 +115,13 @@ public class WebServerRequest extends Thread {
 			synchronized(mgr.lock) {
 				for(TileUpdate tu : mgr.tileUpdates) {
 					if(tu.at >= cutoff) {
-						sb.append(tu.tile.px + "_" + tu.tile.py + " " + tu.tile.zpx + "_" + tu.tile.zpy + "\n");
+						sb.append(tu.tile.px + "_" + tu.tile.py + " " + tu.tile.zpx + "_" + tu.tile.zpy + " t\n");
+					}
+				}
+
+				for(TileUpdate tu : mgr.caveTileUpdates) {
+					if(tu.at >= cutoff) {
+						sb.append(tu.tile.px + "_" + tu.tile.py + " " + tu.tile.zpx + "_" + tu.tile.zpy + " c\n");
 					}
 				}
 			}
diff --git a/dist/DynamicMap.rar b/dist/DynamicMap.rar
index 1e85c2dd..b37895cd 100644
Binary files a/dist/DynamicMap.rar and b/dist/DynamicMap.rar differ
diff --git a/web/book.png b/web/book.png
new file mode 100644
index 00000000..727dcdae
Binary files /dev/null and b/web/book.png differ
diff --git a/web/cave_off.png b/web/cave_off.png
new file mode 100644
index 00000000..500d9872
Binary files /dev/null and b/web/cave_off.png differ
diff --git a/web/cave_on.png b/web/cave_on.png
new file mode 100644
index 00000000..06395767
Binary files /dev/null and b/web/cave_on.png differ
diff --git a/web/index.html b/web/index.html
index 4a579481..f48964f4 100644
--- a/web/index.html
+++ b/web/index.html
@@ -16,7 +16,9 @@
 </head> 
 <body> 
 	<div id="mcmap"></div> 
-	<div id="plist" style="display:none;"><img id="plistbtn" alt="on" src="list_on.png" onclick="plistopen()" title="Player list" /> 
+	<div id="plist" style="display:none;">
+		<img id="plistbtn" alt="on" src="list_on.png" onclick="plistopen()" title="Toggle Player List" />
+		<img id="cavebtn" src="cave_off.png" title="Toggle X-Ray" onclick="caveSwitch()">
 		<div id="lst">[Connecting]</div> 
 	</div> 
 	<div id="controls" style="display:none;"> 
diff --git a/web/map.js b/web/map.js
index 8d7fe489..2d8532ba 100644
--- a/web/map.js
+++ b/web/map.js
@@ -18,10 +18,10 @@ var setup = {
  */
 function MarkerLabel_(marker) {
   this.marker_ = marker;
- 
+
   this.labelDiv_ = document.createElement("div");
   this.labelDiv_.style.cssText = "position: absolute; overflow: hidden;";
- 
+
   // Set up the DIV for handling mouse events in the label. This DIV forms a transparent veil
   // in the "overlayMouseTarget" pane, a veil that covers just the label. This is done so that
   // events can be captured even if the label is in the shadow of a google.maps.InfoWindow.
@@ -29,10 +29,10 @@ function MarkerLabel_(marker) {
   this.eventDiv_ = document.createElement("div");
   this.eventDiv_.style.cssText = this.labelDiv_.style.cssText;
 }
- 
+
 // MarkerLabel_ inherits from OverlayView:
 MarkerLabel_.prototype = new google.maps.OverlayView();
- 
+
 /**
  * Adds the DIV representing the label to the DOM. This method is called
  * automatically when the marker's <code>setMap</code> method is called.
@@ -46,7 +46,7 @@ MarkerLabel_.prototype.onAdd = function () {
   var cSavedZIndex;
   var cLatOffset, cLngOffset;
   var cIgnoreClick;
- 
+
   // Stops all processing of an event.
   //
   var cAbortEvent = function (e) {
@@ -58,10 +58,10 @@ MarkerLabel_.prototype.onAdd = function () {
       e.stopPropagation();
     }
   };
- 
+
   this.getPanes().overlayImage.appendChild(this.labelDiv_);
   this.getPanes().overlayMouseTarget.appendChild(this.eventDiv_);
- 
+
   this.listeners_ = [
     google.maps.event.addDomListener(document, "mouseup", function (mEvent) {
       if (cDraggingInProgress) {
@@ -156,7 +156,7 @@ MarkerLabel_.prototype.onAdd = function () {
     })
   ];
 };
- 
+
 /**
  * Removes the DIV for the label from the DOM. It also removes all event handlers.
  * This method is called automatically when the marker's <code>setMap(null)</code>
@@ -167,13 +167,13 @@ MarkerLabel_.prototype.onRemove = function () {
   var i;
   this.labelDiv_.parentNode.removeChild(this.labelDiv_);
   this.eventDiv_.parentNode.removeChild(this.eventDiv_);
- 
+
   // Remove event listeners:
   for (i = 0; i < this.listeners_.length; i++) {
     google.maps.event.removeListener(this.listeners_[i]);
   }
 };
- 
+
 /**
  * Draws the label on the map.
  * @private
@@ -183,7 +183,7 @@ MarkerLabel_.prototype.draw = function () {
   this.setTitle();
   this.setStyles();
 };
- 
+
 /**
  * Sets the content of the label.
  * The content can be plain text or an HTML DOM node.
@@ -200,7 +200,7 @@ MarkerLabel_.prototype.setContent = function () {
     this.eventDiv_.appendChild(content);
   }
 };
- 
+
 /**
  * Sets the content of the tool tip for the label. It is
  * always set to be the same as for the marker itself.
@@ -209,7 +209,7 @@ MarkerLabel_.prototype.setContent = function () {
 MarkerLabel_.prototype.setTitle = function () {
   this.eventDiv_.title = this.marker_.getTitle() || "";
 };
- 
+
 /**
  * Sets the style of the label by setting the style sheet and applying
  * other specific styles requested.
@@ -217,11 +217,11 @@ MarkerLabel_.prototype.setTitle = function () {
  */
 MarkerLabel_.prototype.setStyles = function () {
   var i, labelStyle;
- 
+
   // Apply style values from the style sheet defined in the labelClass parameter:
   this.labelDiv_.className = this.marker_.get("labelClass");
   this.eventDiv_.className = this.labelDiv_.className;
- 
+
   // Clear existing inline style values:
   this.labelDiv_.style.cssText = "";
   this.eventDiv_.style.cssText = "";
@@ -235,7 +235,7 @@ MarkerLabel_.prototype.setStyles = function () {
   }
   this.setMandatoryStyles();
 };
- 
+
 /**
  * Sets the mandatory styles to the DIV representing the label as well as to the
  * associated event DIV. This includes setting the DIV position, zIndex, and visibility.
@@ -248,7 +248,7 @@ MarkerLabel_.prototype.setMandatoryStyles = function () {
   if (typeof this.labelDiv_.style.opacity !== "undefined") {
     this.labelDiv_.style.filter = "alpha(opacity=" + (this.labelDiv_.style.opacity * 100) + ")";
   }
- 
+
   this.eventDiv_.style.position = this.labelDiv_.style.position;
   this.eventDiv_.style.overflow = this.labelDiv_.style.overflow;
   this.eventDiv_.style.opacity = 0.01; // Don't use 0; DIV won't be clickable on MSIE
@@ -258,7 +258,7 @@ MarkerLabel_.prototype.setMandatoryStyles = function () {
   this.setPosition(); // This also updates zIndex, if necessary.
   this.setVisible();
 };
- 
+
 /**
  * Sets the anchor point of the label.
  * @private
@@ -270,7 +270,7 @@ MarkerLabel_.prototype.setAnchor = function () {
   this.eventDiv_.style.marginLeft = -anchor.x + "px";
   this.eventDiv_.style.marginTop = -anchor.y + "px";
 };
- 
+
 /**
  * Sets the position of the label. The zIndex is also updated, if necessary.
  * @private
@@ -282,10 +282,10 @@ MarkerLabel_.prototype.setPosition = function () {
   this.labelDiv_.style.top = position.y + "px";
   this.eventDiv_.style.left = this.labelDiv_.style.left;
   this.eventDiv_.style.top = this.labelDiv_.style.top;
- 
+
   this.setZIndex();
 };
- 
+
 /**
  * Sets the zIndex of the label. If the marker's zIndex property has not been defined, the zIndex
  * of the label is set to the vertical coordinate of the label. This is in keeping with the default
@@ -302,7 +302,7 @@ MarkerLabel_.prototype.setZIndex = function () {
     this.eventDiv_.style.zIndex = this.labelDiv_.style.zIndex;
   }
 };
- 
+
 /**
  * Sets the visibility of the label. The label is visible only if the marker itself is
  * visible (i.e., its visible property is true) and the labelVisible property is true.
@@ -316,7 +316,7 @@ MarkerLabel_.prototype.setVisible = function () {
   }
   this.eventDiv_.style.display = this.labelDiv_.style.display;
 };
- 
+
 /**
  * @name MarkerWithLabelOptions
  * @class This class represents the optional parameter passed to the {@link MarkerWithLabel} constructor.
@@ -370,27 +370,29 @@ function MarkerWithLabel(opt_options) {
   if (typeof opt_options.labelVisible === "undefined") {
     opt_options.labelVisible = true;
   }
- 
+
   this.label = new MarkerLabel_(this); // Bind the label to the marker
- 
+
   // Call the parent constructor. It calls Marker.setValues to initialize, so all
   // the new parameters are conveniently saved and can be accessed with get/set.
   // Marker.set triggers a property changed event (called "propertyname_changed")
   // that the marker label listens for in order to react to state changes.
   google.maps.Marker.apply(this, arguments);
 }
- 
+
 // MarkerWithLabel inherits from <code>Marker</code>:
 MarkerWithLabel.prototype = new google.maps.Marker();
- 
+
 MarkerWithLabel.prototype.setMap = function (theMap) {
   // Call the inherited function...
   google.maps.Marker.prototype.setMap.apply(this, arguments);
- 
+
   // ... then deal with the label:
   this.label.setMap(theMap);
 };
- 
+
+
+
 /* generic function for making an XMLHttpRequest
  *  url:   request URL
  *  func:  callback function for success
@@ -404,16 +406,16 @@ MarkerWithLabel.prototype.setMap = function (theMap) {
 function makeRequest(url, func, type, fail, post, contenttype)
 {
 	var http_request = false;
- 
+
 	type = typeof(type) != 'undefined' ? type : 'text';
 	fail = typeof(fail) != 'undefined' ? fail : function() { };
- 
+
 	if(window.XMLHttpRequest) {
 		http_request = new XMLHttpRequest();
 	} else if(window.ActiveXObject) {
 		http_request = new ActiveXObject("Microsoft.XMLHTTP");
 	}
- 
+
 	if(type == 'text') {
 		http_request.onreadystatechange = function() {
 			if(http_request.readyState == 4) {
@@ -433,7 +435,7 @@ function makeRequest(url, func, type, fail, post, contenttype)
 			}
 		}
 	}
- 
+
 	if(typeof(post) != 'undefined') {
 		http_request.open('POST', url, true);
 		if(typeof(contenttype) != 'undefined')
@@ -454,9 +456,9 @@ function makeRequest(url, func, type, fail, post, contenttype)
 		updateRate:  setup.updateRate,
 		zoomSize:    [ 128, 128, 256, 512 ]
 	};
- 
+
 	function MCMapProjection() {
-	}
+	  }
 
 	MCMapProjection.prototype.fromLatLngToPoint = function(latLng) {
 		var x = (latLng.lng() * config.tileWidth)|0;
@@ -476,7 +478,7 @@ function makeRequest(url, func, type, fail, post, contenttype)
 		var lat = point.y / config.tileHeight;
 		return new google.maps.LatLng(lat, lng);
 	};
- 
+
 	function fromWorldToLatLng(x, y, z)
 	{
 		var dx = +x;
@@ -484,19 +486,19 @@ function makeRequest(url, func, type, fail, post, contenttype)
 		var dz = +z;
 		var px = dx + dz;
 		var py = dx - dz - dy;
- 
+
 		var lng = -px / config.tileWidth / 2 + 0.5;
 		var lat = py / config.tileHeight / 2;
- 
+
 		return new google.maps.LatLng(lat, lng);
 	}
- 
+
 	function mcMapType() {
 	}
- 
+
 	var tileDict = new Array();
 	var lastSeen = new Array();
- 
+
 	function tileUrl(tile, always) {
 		if(always) {
 			var now = new Date();
@@ -507,11 +509,11 @@ function makeRequest(url, func, type, fail, post, contenttype)
 			return config.tileUrl + tile + '.png?0';
 		}
 	}
- 
+
 	function imgSubst(tile) {
 		if(!(tile in tileDict))
 			return;
- 
+
 		var src = tileUrl(tile);
 		var t = tileDict[tile];
 		t.src = src;
@@ -523,40 +525,59 @@ function makeRequest(url, func, type, fail, post, contenttype)
 			t.onerror = '';
 		}
 	}
- 
+
+	var caveMode = false;
+
+	function caveSwitch()
+	{
+		caveMode = !caveMode;
+
+		if(caveMode) {
+			cavebtn.src = 'cave_on.png';
+			map.setMapTypeId('cavemap');
+		} else {
+			cavebtn.src = 'cave_off.png';
+			map.setMapTypeId('mcmap');
+		}
+	}
+
 	mcMapType.prototype.tileSize = new google.maps.Size(config.tileWidth, config.tileHeight);
 	mcMapType.prototype.minZoom = 0;
 	mcMapType.prototype.maxZoom = 3;
 	mcMapType.prototype.getTile = function(coord, zoom, doc) {
 		var img = doc.createElement('IMG');
- 
+
 		img.onerror = function() { img.style.display = 'none'; }
- 
+
 		img.style.width = config.zoomSize[zoom] + 'px';
 		img.style.height = config.zoomSize[zoom] + 'px';
 		img.style.borderStyle = 'none';
- 
+
+		var pfx = caveMode ? "c" : "";
+
 		if(zoom > 0) {
-			var tilename = "t_" + (- coord.x * config.tileWidth) + '_' + coord.y * config.tileHeight;
+			var tilename = pfx + "t_" + (- coord.x * config.tileWidth) + '_' + coord.y * config.tileHeight;
 		} else {
-			var tilename = "zt_" + (- coord.x * config.tileWidth * 2) + '_' + coord.y * config.tileHeight * 2;
+			var tilename = pfx + "zt_" + (- coord.x * config.tileWidth * 2) + '_' + coord.y * config.tileHeight * 2;
 		}
+
 		tileDict[tilename] = img;
- 
+
 		var url = tileUrl(tilename);
 		img.src = url;
 		//img.style.background = 'url(' + url + ')';
 		//img.innerHTML = '<small>' + tilename + '</small>';
- 
+
 		return img;
 	}
- 
+
 	var markers = new Array();
 	var lasttimestamp = 0;
 	var followPlayer = '';
- 
+
 	var lst;
 	var plistbtn;
+	var cavebtn;
 	var lstopen = true;
 	var oldplayerlst = '[Connecting]';
 
@@ -650,11 +671,24 @@ function makeRequest(url, func, type, fail, post, contenttype)
 						
 						markers[p[0]] = marker;
 					}
-				} else if(p.length == 2) {
-					lastSeen['t_' + p[0]] = lasttimestamp;
-					lastSeen['zt_' + p[1]] = lasttimestamp;
-					imgSubst('t_' + p[0]);
-					imgSubst('zt_' + p[1]);
+				} else if(p.length == 3) {
+					if(p[2] == 't') {
+						lastSeen['t_' + p[0]] = lasttimestamp;
+						lastSeen['zt_' + p[1]] = lasttimestamp;
+
+						if(!caveMode) {
+							imgSubst('t_' + p[0]);
+							imgSubst('zt_' + p[1]);
+						}
+					} else {
+						lastSeen['ct_' + p[0]] = lasttimestamp;
+						lastSeen['czt_' + p[1]] = lasttimestamp;
+
+						if(caveMode) {
+							imgSubst('ct_' + p[0]);
+							imgSubst('czt_' + p[1]);
+						}
+					}
 				}
 			}
  
@@ -682,6 +716,8 @@ function makeRequest(url, func, type, fail, post, contenttype)
 	window.onload = function initialize() {
 		lst = document.getElementById('lst');
 		plistbtn = document.getElementById('plistbtn');
+		cavebtn = document.getElementById('cavebtn');
+
 		var mapOptions = {
 			zoom: 1,
 			center: new google.maps.LatLng(0, 1),
@@ -698,10 +734,14 @@ function makeRequest(url, func, type, fail, post, contenttype)
 		map = new google.maps.Map(document.getElementById("mcmap"), mapOptions);
 		mapType = new mcMapType();
 		mapType.projection = new MCMapProjection();
+		caveMapType = new mcMapType();
+		caveMapType.projection = new MCMapProjection();
+
 		map.zoom_changed = function() {
 			mapType.tileSize = new google.maps.Size(config.zoomSize[map.zoom], config.zoomSize[map.zoom]);
+			caveMapType.tileSize = mapType.tileSize;
 		};
- 
+
 		google.maps.event.addListener(map, 'dragstart', function(mEvent) {
 				plfollow('');
 			});
@@ -711,13 +751,15 @@ function makeRequest(url, func, type, fail, post, contenttype)
 		google.maps.event.addListener(map, 'center_changed', function() {
 				makeLink();
 			});
- 
 		map.dragstart = plfollow('');
+
 		map.mapTypes.set('mcmap', mapType);
+		map.mapTypes.set('cavemap', caveMapType);
+
 		map.setMapTypeId('mcmap');
 		mapUpdate();
 	}
- 
+
 	function plistopen() {
 		if(lstopen) {
 			lstopen = false;
@@ -731,36 +773,36 @@ function makeRequest(url, func, type, fail, post, contenttype)
 			plistbtn.src = 'list_on.png';
 		}
 	}
- 
+
 	function plclick(name) {
 		if(name in markers) {
 			if(name != followPlayer) plfollow('');
 			map.panTo(markers[name].getPosition());
 		}
 	}
- 
+
 	function plfollow(name) {
 		var icon;
- 
+
 		if(followPlayer == name) {
 			icon = document.getElementById('icon_' + followPlayer);
 			if(icon) icon.src = 'follow_off.png';
 			followPlayer = '';
 			return;
 		}
- 
+
 		if(followPlayer) {
 			icon = document.getElementById('icon_' + followPlayer);
 			if(icon) icon.src = 'follow_off.png';
 			followPlayer = '';
 		}
- 
+
 		if(!name) return;
- 
+
 		icon = document.getElementById('icon_' + name);
 		if(icon) icon.src = 'follow_on.png';
 		followPlayer = name;
- 
+
 		if(name in markers) {
 			map.panTo(markers[name].getPosition());
 		}
diff --git a/web/style.css b/web/style.css
index ae63a021..3d1fff04 100644
--- a/web/style.css
+++ b/web/style.css
@@ -20,6 +20,10 @@ body { height: 100%; margin: 0px; padding: 0px ; background-color: #000; }
 	float:right;
 	cursor:pointer;
 }
+#cavebtn {
+	float:right;
+	cursor:pointer;
+}
 #link {
 	position: absolute;
 	bottom: 4px;
@@ -68,4 +72,5 @@ a, a:visited {
 	display:inline-block;
 	height:14px;width:14px;
 	background-color:#000;
+	border: 0px;
 }