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mcexplore.py

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+
+#!/usr/bin/python
+
+# mcexplore.py, by similardilemma
+# Released under the Creative Commons Attribution-ShareAlike license:
+# http://creativecommons.org/licenses/by-sa/3.0/
+
+# This script requires a copy of twoolie's nbt.py, found here: https://github.com/twoolie/NBT
+
+import os
+import sys
+import shutil
+import optparse
+import subprocess
+import math
+
+import nbt
+
+def main():
+    # handle command line options and args
+    version = "%prog 1.0"
+    usage = "usage: %prog [options] xsize zsize"
+    description = "Uses a Minecraft server to generate square land of a specified size, measured in chunks (16x16 blocks) or regions (32x32 chunks). If only xsize is specified, it is used for both xsize and zsize. Either run this from the folder containing your minecraft server, or specify the path to your minecraft folder with the -p option."
+    parser = optparse.OptionParser(version=version, usage=usage, description=description)
+    parser.add_option("-v", "--verbose", action="store_true", dest="verbose", default=False, help="When enabled, the Minecraft server output is shown on the console")
+    parser.add_option("-p", "--path", dest="path", default=".", help="sets the current directory to use when running the server")
+    parser.add_option("-c", "--command", dest="command", default=("java", "-jar", "minecraft_server.jar", "nogui"), help="Specifies the command used to start the server. Defaults to 'java -jar minecraft_server.jar nogui'")
+    parser.add_option("-x", dest="xorigin", type="int", help="Set the X offset to generate land around. Defaults to the server's spawn point")
+    parser.add_option("-z", dest="zorigin", type="int", help="Set the Z offset to generate land around. Defaults to the server's spawn point")
+    parser.add_option("-r", "--regions", action="store_true", dest="regions", default=False, help="When enabled, measure in regions instead of chunks.")
+    (options, args) = parser.parse_args()
+
+    # exit with an error if no arguments were passed
+    if len(args) == 0:
+        print "You must specify a size. Use -h for help."
+        sys.exit(1)
+
+    # if only an xsize was specified, use it for the zsize as well
+    if len(args) == 1:
+        args.append(args[0])
+
+    # exit with an error if a size smaller than the initial spawn was specified
+    if options.regions:
+        multiplier = 512
+        if int(args[0]) < 2 or int(args[1]) < 2:
+            print "When specifying sizes in regions, you must specify an area 2x2 or larger."
+            sys.exit(1)
+    else:
+        multiplier = 16
+        if int(args[0]) <= 25 or int(args[1]) <= 25:
+            print "Minecraft maps start with a 25x25 chunk square. You must specify sizes larger than this."
+            sys.exit(1)
+
+    # parse the server.properties file to get the world name
+    properties = parseConfig(os.path.join(options.path, 'server.properties'))
+    world = os.path.join(options.path, properties['level-name'])
+
+    # make a backup of the level.dat file for later restoration
+    level = os.path.join(options.path, world, "level.dat")
+    levelbak = os.path.join(options.path, world, "level.dat.explorebackup")
+
+    # don't do anything if a backup already exists. Since we always clean up our backups, a leftover backup means something went wrong last time.
+    if os.path.isfile(levelbak):
+        print "A backup of your level.dat file exists. This means that you've run this program before and it failed, was interrupted, or is still running. You will need to restore or delete this backup before trying again."
+        sys.exit(1)
+
+    # make our backup
+    shutil.copyfile(level, levelbak)
+
+    # find the server's original spawn point
+    originalspawn = getSpawn(level)
+
+    # use the spawn point as the origin if none was specified
+    if options.xorigin is None: options.xorigin = originalspawn[0]
+    if options.zorigin is None: options.zorigin = originalspawn[2]
+
+    # move the origin to the nearest valid center point
+    # this will be a region or chunk center, the center of a region or chunk border,
+    # or the corner of a region or chunk, depending on the specified dimensions
+    # this is not strictly necessary when measuring in chunks, but doesn't hurt
+    xoffset = (int(args[0]) % 2) * (multiplier / 2)
+    zoffset = (int(args[1]) % 2) * (multiplier / 2)
+    options.xorigin = int(round(float(options.xorigin + xoffset) / float(multiplier))) * multiplier - xoffset
+    options.zorigin = int(round(float(options.zorigin + zoffset) / float(multiplier))) * multiplier - zoffset
+    print "Snapped origin to %d, %d" % (options.xorigin, options.zorigin)
+
+    # loop through a grid of spawn points within the given range, starting and stopping the server for each one
+    # note that the server generated spawn point is 400x400 meters (25x25 chunks)
+    xsize = int(args[0]) * multiplier - 400
+    zsize = int(args[1]) * multiplier - 400
+    print "Size of area to map in meters: %d, %d" % (xsize + 400, zsize + 400)
+    xiterations = int(math.ceil(xsize / 400.0) + 1)
+    ziterations = int(math.ceil(zsize / 400.0) + 1)
+    for xcount in range(0, xiterations):
+        x = options.xorigin - xsize / 2 + xcount * 400
+        if x > options.xorigin + xsize / 2: x = options.xorigin + xsize / 2
+        for zcount in range(0, ziterations):
+            z = options.zorigin - zsize / 2 + zcount * 400
+            if z > options.zorigin + zsize / 2: z = options.zorigin + zsize / 2
+            print "Setting spawn to %d, %d" % (x, z)
+            setSpawn(level, (x, 64, z))
+            runMinecraft(options.path, options.command, options.verbose)
+
+    # restore the old spawn point
+    print "Restoring original spawn of %d, %d, %d" % originalspawn
+    os.remove(level)
+    os.rename(levelbak, level)
+
+def getSpawn(level):
+    """Gets the spawn point from a given level.dat file"""
+    data = nbt.NBTFile(level,'rb')["Data"]
+    return (data['SpawnX'].value, data['SpawnY'].value, data['SpawnZ'].value)
+
+def setSpawn(level, coords):
+    """Sets the spawn point in a given level.dat file"""
+    f = nbt.NBTFile(level,'rb')
+    (f["Data"]["SpawnX"].value, f["Data"]["SpawnY"].value, f["Data"]["SpawnZ"].value) = coords
+    f.write_file(level)
+
+def runMinecraft(path, command, verbose=False):
+    """Runs a minecraft server, and stops it as soon as possible."""
+    if verbose:
+        outstream = sys.stdout
+    else:
+        outstream = subprocess.PIPE
+    mc = subprocess.Popen(command, stdin=subprocess.PIPE, stdout=outstream, stderr=subprocess.STDOUT, cwd=path)
+    mc.stdin.write("stop\r\n")
+    mc.wait()
+
+def parseConfig(filename):
+    """Parses a server.properties file. Accepts the path to the file as an argument, and returns the key/value pairs."""
+    properties = {}
+    f = open(filename, 'r')
+    for line in f:
+        line = line.strip()
+        if not line.startswith("#"):
+            (key, sep, val) = line.partition("=")
+            properties[key] = val
+    return properties
+
+if __name__ == "__main__":
+    main()