New findSigns.py contrib script

This can be used to create an complete overviewer.dat file without
having to re-render your entire world.  See the top of the script for
usage details

contrib/findSigns.py

@@ -0,0 +1,64 @@
+#!/usr/bin/python
+
+'''
+This script will scan through every chunk looking for signs and write out an
+updated overviewer.dat file.  This can be useful if your overviewer.dat file
+is either out-of-date or non-existant.  
+
+To run, simply give a path to your world directory, for example:
+
+    python contrib/findSigns.py ../world.test/
+
+Once that is done, simply re-run the overviewer to generate markers.js:
+
+    python gmap.py ../world.test/ output_dir/
+
+Note: if your cachedir is not the same as your world-dir, you'll need to manually
+move overviewer.dat into the correct location.
+
+'''
+import sys
+import re
+import os
+import cPickle
+
+sys.path.append(".")
+import nbt
+
+from pprint import pprint
+
+worlddir = sys.argv[1]
+if os.path.exists(worlddir):
+    print "Scanning chunks in ", worlddir
+else:
+    sys.exit("Bad WorldDir")
+
+matcher = re.compile(r"^c\..*\.dat$")
+
+POI = []
+
+for dirpath, dirnames, filenames in os.walk(worlddir):
+    for f in filenames:
+        if matcher.match(f):
+            full = os.path.join(dirpath, f)
+            #print "inspecting %s" % full
+            data = nbt.load(full)[1]['Level']['TileEntities']
+            for entity in data:
+                if entity['id'] == 'Sign':
+                    newPOI = dict(type="sign",
+                                    x= entity['x'],
+                                    y= entity['y'],
+                                    z= entity['z'],
+                                    msg="%s\n%s\n%s\n%s" %
+                                       (entity['Text1'], entity['Text2'], entity['Text3'], entity['Text4']),
+                                    chunk= (entity['x']/16, entity['z']/16),
+                                   )
+                    POI.append(newPOI)
+                    print "Found sign at (%d, %d, %d): %r" % (newPOI['x'], newPOI['y'], newPOI['z'], newPOI['msg'])
+
+
+
+pickleFile = os.path.join(worlddir,"overviewer.dat")
+with open(pickleFile,"wb") as f:
+    cPickle.dump(dict(POI=POI), f)
+