mclevel.py

# -*- coding: utf-8 -*-
"""
MCLevel interfaces

Sample usage:

import mclevel

# Call mclevel.fromFile to identify and open any of these four file formats:
#
# Classic levels - gzipped serialized java objects.  Returns an instance of MCJavalevel
# Indev levels - gzipped NBT data in a single file.  Returns an MCIndevLevel
# Schematics - gzipped NBT data in a single file.  Returns an MCSchematic.  
#   MCSchematics have the special method rotateLeft which will reorient torches, stairs, and other tiles appropriately.
# Alpha levels - world folder structure containing level.dat and chunk folders.  Single or Multiplayer.
#   Can accept a path to the world folder or a path to the level.dat.  Returns an MCInfdevOldLevel

# Load a Classic level.
level = mclevel.fromFile("server_level.dat"); 

# fromFile identified the file type and returned a MCJavaLevel.  MCJavaLevel doesn't actually know any java. It guessed the
# location of the Blocks array by starting at the end of the file and moving backwards until it only finds valid blocks.
# It also doesn't know the dimensions of the level.  This is why you have to tell them to MCEdit via the filename.
# This works here too:  If the file were 512 wide, 512 long, and 128 high, I'd have to name it "server_level_512_512_128.dat"
#
# This is one area for improvement.

# Classic and Indev levels have all of their blocks in one place.
blocks = level.Blocks

# Sand to glass.
blocks[blocks == level.materials.Sand.ID] = level.materials.Glass.ID

# Save the file with another name.  This only works for non-Alpha levels.
level.saveToFile("server_level_glassy.dat");

# Load an Alpha world
# Loading an Alpha world immediately scans the folder for chunk files.  This takes longer for large worlds.
ourworld = mclevel.fromFile("C:\\Minecraft\\OurWorld");

# Convenience method to load a numbered world from the saves folder.
world1 = mclevel.loadWorldNumber(1);

# Find out which chunks are present. Doing this will scan the chunk folders the
# first time it is used. If you already know where you want to be, skip to 
# world1.getChunk(xPos, zPos)

chunkPositions = list(world1.allChunks)

# allChunks returns an iterator that yields a (xPos, zPos) tuple for each chunk
xPos, zPos = chunkPositions[0];

# retrieve an InfdevChunk object. this object will load and decompress 
# the chunk as needed, and remember whether it needs to be saved or relighted

chunk = world1.getChunk(xPos, zPos)

### Access the data arrays of the chunk like so:
# Take note that the array is indexed x, z, y.  The last index corresponds to 
# height or altitude.

blockType = chunk.Blocks[0,0,64]
chunk.Blocks[0,0,64] = 1

# Access the chunk's Entities and TileEntities as arrays of TAG_Compound as 
# they appear in the save format. 

# Entities usually have Pos, Health, and id
# TileEntities usually have tileX, tileY, tileZ, and id
# For more information, google "Chunk File Format"

for entity in chunk.Entities:
    if entity["id"].value == "Spider":
        entity["Health"].value = 50


# Accessing one byte at a time from the Blocks array is very slow in Python. 
# To get around this, we have methods to access multiple bytes at once.
# The first technique is slicing. You can use slicing to restrict your access
# to certain depth levels, or to extract a column or a larger section from the
# array. Standard python slice notation is used.

# Set the top half of the array to 0. The : says to use the entire array along
# that dimension. The syntax []= indicates we are overwriting part of the array
chunk.Blocks[:,:,64:] = 0

# Using [] without =  creates a 'view' on part of the array.  This is not a 
# copy, it is a reference to a portion of the original array.
midBlocks = chunk.Blocks[:,:,32:64]

# Here's a gotcha:  You can't just write 'midBlocks = 0' since it will replace
# the 'midBlocks' reference itself instead of accessing the array. Instead, do
# this to access and overwrite the array using []= syntax.
midBlocks[:] = 0
 

# The second is masking.  Using a comparison operator ( <, >, ==, etc ) 
# against the Blocks array will return a 'mask' that we can use to specify
# positions in the array.
 
# Create the mask from the result of the equality test.
fireBlocks = ( chunk.Blocks==world.materials.Fire.ID )

# Access Blocks using the mask to set elements. The syntax is the same as 
# using []= with slices
chunk.Blocks[fireBlocks] = world.materials.Leaves.ID

# You can also combine mask arrays using logical operations (&, |, ^) and use
# the mask to access any other array of the same shape.
# Here we turn all trees into birch trees.

# Extract a mask from the Blocks array to find the locations of tree trunks.
# Or | it with another mask to find the locations of leaves.
# Use the combined mask to access the Data array and set those locations to birch

# Note that the Data, BlockLight, and SkyLight arrays have been 
# unpacked from 4-bit arrays to numpy uint8 arrays. This makes them much easier
# to work with.

treeBlocks = ( chunk.Blocks == world.materials.Wood.ID )
treeBlocks |= ( chunk.Blocks == world.materials.Leaves.ID )
chunk.Data[treeBlocks] = 2 # birch


# The chunk doesn't know you've changed any of that data.  Call chunkChanged()
# to let it know. This will mark the chunk for lighting calculation, 
# recompression, and writing to disk. It will also immediately recalculate the 
# chunk's HeightMap and fill the SkyLight only with light falling straight down. 
# These are relatively fast and were added here to aid MCEdit.

chunk.chunkChanged();

# To recalculate all of the dirty lights in the world, call generateLights
world.generateLights();


# Move the player and his spawn
world.setPlayerPosition( (0, 67, 0) ) # add 3 to make sure his head isn't in the ground.
world.setPlayerSpawnPosition( (0, 64, 0) )


# Save the level.dat and any chunks that have been marked for writing to disk
# This also compresses any chunks marked for recompression.
world.saveInPlace();


# Advanced use:
# The getChunkSlices method returns an iterator that returns slices of chunks within the specified range.
# the slices are returned as tuples of (chunk, slices, point)

# chunk:  The InfdevChunk object we're interested in.
# slices:  A 3-tuple of slice objects that can be used to index chunk's data arrays
# point:  A 3-tuple of floats representing the relative position of this subslice within the larger slice.
# 
# Take caution:
# the point tuple is ordered (x,y,z) in accordance with the tuples used to initialize a bounding box
# however, the slices tuple is ordered (x,z,y) for easy indexing into the arrays.

# Here is an old version of MCInfdevOldLevel.fillBlocks in its entirety:

def fillBlocks(self, box, blockType, blockData = 0):
    chunkIterator = self.getChunkSlices(box)
    
    for (chunk, slices, point) in chunkIterator:
        chunk.Blocks[slices] = blockType
        chunk.Data[slices] = blockData
        chunk.chunkChanged();


Copyright 2010 David Rio Vierra
"""
import os
import logging
from numpy import fromstring
import nbt

from mclevelbase import *
from indev import *
from infiniteworld import *
from java import *
from level import *
from schematic import *
from pocket import *

import sys

log = logging.getLogger(__name__)
warn, error, info, debug = log.warn, log.error, log.info, log.debug


 

    

class LoadingError(RuntimeError): pass

def fromFile(filename, loadInfinite=True):
    ''' The preferred method for loading Minecraft levels of any type.
    pass False to loadInfinite if you'd rather not load infdev levels.
    '''
    info(u"Identifying " + filename)

    if not filename:
        raise IOError, "File not found: " + filename
    if not os.path.exists(filename):
        raise IOError, "File not found: " + filename

    if ZipSchematic._isLevel(filename):
        info("Zipfile found, attempting zipped infinite level")
        lev = ZipSchematic(filename)
        info("Detected zipped Infdev level")
        return lev

    if PocketWorld._isLevel(filename):
        return PocketWorld(filename)

    if MCInfdevOldLevel._isLevel(filename):
        info(u"Detected Infdev level.dat")
        if loadInfinite:
            return MCInfdevOldLevel(filename=filename)
        else:
            raise ValueError, "Asked to load {0} which is an infinite level, loadInfinite was False".format(os.path.basename(filename))

    if os.path.isdir(filename):
        raise ValueError, "Folder {0} was not identified as a Minecraft level.".format(os.path.basename(filename))

    f = file(filename, 'rb')
    rawdata = f.read()
    f.close()
    if len(rawdata) < 4:
        raise ValueError, "{0} is too small! ({1}) ".format(filename, len(rawdata))




    data = fromstring(rawdata, dtype='uint8')
    if not data.any():
        raise ValueError, "{0} contains only zeroes. This file is damaged beyond repair."


    if MCJavaLevel._isDataLevel(data):
        info(u"Detected Java-style level")
        lev = MCJavaLevel(filename, data)
        lev.compressed = False
        return lev

    #ungzdata = None
    compressed = True
    unzippedData = None
    try:
        unzippedData = gunzip(rawdata)
    except Exception, e:
        info(u"Exception during Gzip operation, assuming {0} uncompressed: {1!r}".format(filename, e))
        if unzippedData is None:
            compressed = False
            unzippedData = rawdata

    #data = 
    data = unzippedData
    if MCJavaLevel._isDataLevel(data):
        info(u"Detected compressed Java-style level")
        lev = MCJavaLevel(filename, data)
        lev.compressed = compressed
        return lev

    try:
        root_tag = nbt.load(buf=data)

    except Exception, e:
        info(u"Error during NBT load: {0!r}".format(e))
        info(traceback.format_exc())
        info(u"Fallback: Detected compressed flat block array, yzx ordered ")
        try:
            lev = MCJavaLevel(filename, data)
            lev.compressed = compressed
            return lev
        except Exception, e2:
            raise LoadingError, ("Multiple errors encountered", e, e2), sys.exc_info()[2]

    else:
        if MCIndevLevel._isTagLevel(root_tag):
            info(u"Detected Indev .mclevel")
            return MCIndevLevel(root_tag, filename)
        if MCSchematic._isTagLevel(root_tag):
            info(u"Detected Schematic.")
            return MCSchematic(root_tag=root_tag, filename=filename)

        if INVEditChest._isTagLevel(root_tag):
            info(u"Detected INVEdit inventory file")
            return INVEditChest(root_tag=root_tag, filename=filename)

    raise IOError, "Cannot detect file type."


def loadWorld(name):
    filename = os.path.join(saveFileDir, name)
    return fromFile(filename)

def loadWorldNumber(i):
    #deprecated
    filename = u"{0}{1}{2}{3}{1}".format(saveFileDir, os.sep, u"World", i)
    return fromFile(filename)