def readChunkCompressed(self, cx, cz):
"""
Read a chunk and return its compression type and the compressed data as a (data, fmt) tuple
"""
cx &= 0x1f
cz &= 0x1f
offset = self._getOffset(cx, cz)
if offset == 0:
raise ChunkNotPresent((cx, cz))
sectorStart = offset >> 8
numSectors = offset & 0xff
if numSectors == 0:
raise ChunkNotPresent((cx, cz))
if sectorStart + numSectors > len(self.freeSectors):
raise ChunkNotPresent((cx, cz))
with file(self.path, "rb") as f:
f.seek(sectorStart * self.SECTOR_BYTES)
data = f.read(numSectors * self.SECTOR_BYTES)
if len(data) < 5:
raise RegionFormatError(
"Chunk %s data is only %d bytes long (expected 5)" %
((cx, cz), len(data)))
# region_debug("REGION LOAD {0},{1} sector {2}".format(cx, cz, sectorStart))
length = struct.unpack_from(">I", data)[0]
fmt = struct.unpack_from("B", data, 4)[0]
data = data[5:length + 5]
return data, fmt
def readChunk(self, cx, cz, dimName, create=False):
"""
Creates a FakeChunkData object representing the chunk at the given
position. Subclasses may choose to override
fakeBlocksForChunk and fakeDataForChunk to provide block and blockdata arrays.
They may instead override getChunk and return a ChunkBase subclass.
By default, returns a chunk whose ``Blocks`` is made from slices of self.Blocks (and
``Data`` from self.Data if present)
"""
if not self.bounds.containsChunk(cx, cz):
raise ChunkNotPresent((cx, cz))
chunk = self.ChunkDataClass()
chunk.dimension = self
chunk.cx = cx
chunk.cz = cz
chunk.dimName = dimName
chunk.Blocks = self.fakeBlocksForChunk(cx, cz)
chunk.Data = self.fakeDataForChunk(cx, cz)
whiteLight = zeros_like(chunk.Blocks)
whiteLight[:] = 15
chunk.BlockLight = whiteLight
chunk.SkyLight = whiteLight
chunk.Entities, chunk.TileEntities = self.fakeEntitiesForChunk(cx, cz)
chunk.rootTag = nbt.TAG_Compound()
return chunk
def loadChunk(self, cx, cz, world):
data = self._readChunk(cx, cz)
if data is None:
raise ChunkNotPresent((cx, cz, self))
chunk = PocketChunk(cx, cz, data[4:], world)
return chunk
def readChunkBytes(self, cx, cz, dimName):
if self.invalid:
raise RuntimeError("Accessing invalid node: %r" % self)
node = self
while node:
# Ask RevisionHistory for most recent node containing this chunk?
if (cx, cz, dimName) in node.deadChunks:
raise ChunkNotPresent((cx, cz), "Chunk was deleted")
if node.worldFolder.containsChunk(cx, cz, dimName):
data = node.worldFolder.readChunkBytes(cx, cz, dimName)
return data
if node is self.history.rootNode:
break
node = node.parentNode
raise ChunkNotPresent((cx, cz))
def getChunk(self, cx, cz, create=False):
for p in cx, cz:
if not 0 <= p <= 31:
raise ChunkNotPresent((cx, cz, self))
c = self._loadedChunks.get((cx, cz))
if c is None:
c = self.chunkFile.loadChunk(cx, cz, self)
self._loadedChunks[cx, cz] = c
return c
def readChunkBytes(self, cx, cz, dimName):
if not self.containsChunk(cx, cz, dimName):
raise ChunkNotPresent((cx, cz))
return self.getRegionForChunk(cx, cz, dimName).readChunkBytes(cx, cz)
