1019 lines
30 KiB
Python
1019 lines
30 KiB
Python
# ***** BEGIN GPL LICENSE BLOCK *****
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#
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# This program is free software; you can redistribute it and/or
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# modify it under the terms of the GNU General Public License
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# as published by the Free Software Foundation; either version 2
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# of the License, or (at your option) any later version.
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#
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License
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# along with this program; if not, write to the Free Software Foundation,
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# Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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#
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# ***** END GPL LICENCE BLOCK *****
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#
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# (c) 2009, At Mind B.V. - Jeroen Bakker
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# (c) 2014, Blender Foundation - Campbell Barton
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import gzip
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import logging
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import os
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import struct
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import tempfile
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log = logging.getLogger("blendfile")
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FILE_BUFFER_SIZE = 1024 * 1024
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# -----------------------------------------------------------------------------
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# module global routines
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#
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# read routines
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# open a filename
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# determine if the file is compressed
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# and returns a handle
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def open_blend(filename, access="rb"):
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"""Opens a blend file for reading or writing pending on the access
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supports 2 kind of blend files. Uncompressed and compressed.
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Known issue: does not support packaged blend files
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"""
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handle = open(filename, access)
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magic_test = b"BLENDER"
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magic = handle.read(len(magic_test))
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if magic == magic_test:
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log.debug("normal blendfile detected")
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handle.seek(0, os.SEEK_SET)
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bfile = BlendFile(handle)
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bfile.is_compressed = False
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bfile.filepath_orig = filename
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return bfile
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elif magic[:2] == b"\x1f\x8b":
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log.debug("gzip blendfile detected")
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handle.close()
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log.debug("decompressing started")
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fs = gzip.open(filename, "rb")
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data = fs.read(FILE_BUFFER_SIZE)
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magic = data[: len(magic_test)]
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if magic == magic_test:
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handle = tempfile.TemporaryFile()
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while data:
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handle.write(data)
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data = fs.read(FILE_BUFFER_SIZE)
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log.debug("decompressing finished")
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fs.close()
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log.debug("resetting decompressed file")
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handle.seek(os.SEEK_SET, 0)
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bfile = BlendFile(handle)
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bfile.is_compressed = True
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bfile.filepath_orig = filename
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return bfile
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else:
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raise Exception("filetype inside gzip not a blend")
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else:
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raise Exception("filetype not a blend or a gzip blend")
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def pad_up_4(offset):
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return (offset + 3) & ~3
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# -----------------------------------------------------------------------------
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# module classes
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class BlendFile:
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"""
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Blend file.
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"""
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__slots__ = (
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# file (result of open())
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"handle",
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# str (original name of the file path)
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"filepath_orig",
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# BlendFileHeader
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"header",
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# struct.Struct
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"block_header_struct",
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# BlendFileBlock
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"blocks",
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# [DNAStruct, ...]
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"structs",
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# dict {b'StructName': sdna_index}
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# (where the index is an index into 'structs')
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"sdna_index_from_id",
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# dict {addr_old: block}
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"block_from_offset",
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# int
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"code_index",
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# bool (did we make a change)
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"is_modified",
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# bool (is file gzipped)
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"is_compressed",
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)
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def __init__(self, handle):
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log.debug("initializing reading blend-file")
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self.handle = handle
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self.header = BlendFileHeader(handle)
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self.block_header_struct = self.header.create_block_header_struct()
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self.blocks = []
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self.code_index = {}
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block = BlendFileBlock(handle, self)
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while block.code != b"ENDB":
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if block.code == b"DNA1":
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(
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self.structs,
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self.sdna_index_from_id,
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) = BlendFile.decode_structs(self.header, block, handle)
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else:
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handle.seek(block.size, os.SEEK_CUR)
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self.blocks.append(block)
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self.code_index.setdefault(block.code, []).append(block)
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block = BlendFileBlock(handle, self)
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self.is_modified = False
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self.blocks.append(block)
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# cache (could lazy init, incase we never use?)
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self.block_from_offset = {
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block.addr_old: block for block in self.blocks if block.code != b"ENDB"
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}
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def __enter__(self):
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return self
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def __exit__(self, type, value, traceback):
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self.close()
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def find_blocks_from_code(self, code):
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assert type(code) == bytes
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if code not in self.code_index:
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return []
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return self.code_index[code]
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def find_block_from_offset(self, offset):
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# same as looking looping over all blocks,
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# then checking ``block.addr_old == offset``
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assert type(offset) is int
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return self.block_from_offset.get(offset)
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def close(self):
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"""
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Close the blend file
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writes the blend file to disk if changes has happened
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"""
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handle = self.handle
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if self.is_modified:
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if self.is_compressed:
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log.debug("close compressed blend file")
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handle.seek(os.SEEK_SET, 0)
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log.debug("compressing started")
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fs = gzip.open(self.filepath_orig, "wb")
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data = handle.read(FILE_BUFFER_SIZE)
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while data:
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fs.write(data)
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data = handle.read(FILE_BUFFER_SIZE)
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fs.close()
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log.debug("compressing finished")
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handle.close()
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def ensure_subtype_smaller(self, sdna_index_curr, sdna_index_next):
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# never refine to a smaller type
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if self.structs[sdna_index_curr].size > self.structs[sdna_index_next].size:
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raise RuntimeError(
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"cant refine to smaller type (%s -> %s)"
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% (
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self.structs[sdna_index_curr].dna_type_id.decode("ascii"),
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self.structs[sdna_index_next].dna_type_id.decode("ascii"),
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)
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)
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@staticmethod
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def decode_structs(header, block, handle):
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"""
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DNACatalog is a catalog of all information in the DNA1 file-block
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"""
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log.debug("building DNA catalog")
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shortstruct = DNA_IO.USHORT[header.endian_index]
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shortstruct2 = struct.Struct(header.endian_str + b"HH")
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intstruct = DNA_IO.UINT[header.endian_index]
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data = handle.read(block.size)
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types = []
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names = []
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structs = []
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sdna_index_from_id = {}
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offset = 8
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names_len = intstruct.unpack_from(data, offset)[0]
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offset += 4
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log.debug("building #%d names" % names_len)
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for i in range(names_len):
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tName = DNA_IO.read_data0_offset(data, offset)
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offset = offset + len(tName) + 1
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names.append(DNAName(tName))
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del names_len
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offset = pad_up_4(offset)
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offset += 4
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types_len = intstruct.unpack_from(data, offset)[0]
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offset += 4
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log.debug("building #%d types" % types_len)
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for i in range(types_len):
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dna_type_id = DNA_IO.read_data0_offset(data, offset)
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# None will be replaced by the DNAStruct, below
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types.append(DNAStruct(dna_type_id))
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offset += len(dna_type_id) + 1
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offset = pad_up_4(offset)
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offset += 4
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log.debug("building #%d type-lengths" % types_len)
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for i in range(types_len):
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tLen = shortstruct.unpack_from(data, offset)[0]
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offset = offset + 2
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types[i].size = tLen
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del types_len
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offset = pad_up_4(offset)
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offset += 4
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structs_len = intstruct.unpack_from(data, offset)[0]
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offset += 4
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log.debug("building #%d structures" % structs_len)
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for sdna_index in range(structs_len):
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d = shortstruct2.unpack_from(data, offset)
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struct_type_index = d[0]
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offset += 4
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dna_struct = types[struct_type_index]
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sdna_index_from_id[dna_struct.dna_type_id] = sdna_index
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structs.append(dna_struct)
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fields_len = d[1]
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dna_offset = 0
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for field_index in range(fields_len):
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d2 = shortstruct2.unpack_from(data, offset)
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field_type_index = d2[0]
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field_name_index = d2[1]
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offset += 4
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dna_type = types[field_type_index]
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dna_name = names[field_name_index]
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if dna_name.is_pointer or dna_name.is_method_pointer:
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dna_size = header.pointer_size * dna_name.array_size
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else:
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dna_size = dna_type.size * dna_name.array_size
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field = DNAField(dna_type, dna_name, dna_size, dna_offset)
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dna_struct.fields.append(field)
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dna_struct.field_from_name[dna_name.name_only] = field
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dna_offset += dna_size
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return structs, sdna_index_from_id
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class BlendFileBlock:
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"""
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Instance of a struct.
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"""
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__slots__ = (
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# BlendFile
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"file",
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"code",
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"size",
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"addr_old",
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"sdna_index",
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"count",
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"file_offset",
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"user_data",
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)
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def __str__(self):
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return (
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"<%s.%s (%s), size=%d at %s>"
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%
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# fields=[%s]
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(
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self.__class__.__name__,
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self.dna_type.dna_type_id.decode("ascii"),
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self.code.decode(),
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self.size,
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# b", ".join(f.dna_name.name_only for f in self.dna_type.fields).decode('ascii'),
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hex(self.addr_old),
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)
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)
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def __init__(self, handle, bfile):
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OLDBLOCK = struct.Struct(b"4sI")
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self.file = bfile
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self.user_data = None
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data = handle.read(bfile.block_header_struct.size)
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# header size can be 8, 20, or 24 bytes long
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# 8: old blend files ENDB block (exception)
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# 20: normal headers 32 bit platform
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# 24: normal headers 64 bit platform
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if len(data) > 15:
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blockheader = bfile.block_header_struct.unpack(data)
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self.code = blockheader[0].partition(b"\0")[0]
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if self.code != b"ENDB":
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self.size = blockheader[1]
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self.addr_old = blockheader[2]
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self.sdna_index = blockheader[3]
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self.count = blockheader[4]
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self.file_offset = handle.tell()
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else:
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self.size = 0
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self.addr_old = 0
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self.sdna_index = 0
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self.count = 0
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self.file_offset = 0
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else:
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blockheader = OLDBLOCK.unpack(data)
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self.code = blockheader[0].partition(b"\0")[0]
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self.code = DNA_IO.read_data0(blockheader[0])
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self.size = 0
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self.addr_old = 0
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self.sdna_index = 0
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self.count = 0
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self.file_offset = 0
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@property
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def dna_type(self):
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return self.file.structs[self.sdna_index]
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def refine_type_from_index(self, sdna_index_next):
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assert type(sdna_index_next) is int
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sdna_index_curr = self.sdna_index
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self.file.ensure_subtype_smaller(sdna_index_curr, sdna_index_next)
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self.sdna_index = sdna_index_next
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def refine_type(self, dna_type_id):
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assert type(dna_type_id) is bytes
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self.refine_type_from_index(self.file.sdna_index_from_id[dna_type_id])
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def get_file_offset(
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self,
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path,
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default=...,
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sdna_index_refine=None,
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base_index=0,
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):
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"""
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Return (offset, length)
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"""
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assert type(path) is bytes
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ofs = self.file_offset
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if base_index != 0:
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assert base_index < self.count
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ofs += (self.size // self.count) * base_index
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self.file.handle.seek(ofs, os.SEEK_SET)
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if sdna_index_refine is None:
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sdna_index_refine = self.sdna_index
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else:
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self.file.ensure_subtype_smaller(self.sdna_index, sdna_index_refine)
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dna_struct = self.file.structs[sdna_index_refine]
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field = dna_struct.field_from_path(self.file.header, self.file.handle, path)
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return (self.file.handle.tell(), field.dna_name.array_size)
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def get(
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self,
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path,
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default=...,
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sdna_index_refine=None,
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use_nil=True,
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use_str=True,
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base_index=0,
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):
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ofs = self.file_offset
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if base_index != 0:
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assert base_index < self.count
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ofs += (self.size // self.count) * base_index
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self.file.handle.seek(ofs, os.SEEK_SET)
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if sdna_index_refine is None:
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sdna_index_refine = self.sdna_index
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else:
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self.file.ensure_subtype_smaller(self.sdna_index, sdna_index_refine)
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dna_struct = self.file.structs[sdna_index_refine]
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return dna_struct.field_get(
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self.file.header,
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self.file.handle,
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path,
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default=default,
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use_nil=use_nil,
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use_str=use_str,
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)
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def get_recursive_iter(
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self,
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path,
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path_root=b"",
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default=...,
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sdna_index_refine=None,
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use_nil=True,
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use_str=True,
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base_index=0,
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):
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if path_root:
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path_full = (path_root if type(path_root) is tuple else (path_root,)) + (
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path if type(path) is tuple else (path,)
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)
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else:
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path_full = path
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try:
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yield (
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path_full,
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self.get(
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path_full, default, sdna_index_refine, use_nil, use_str, base_index
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),
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)
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except NotImplementedError as ex:
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msg, dna_name, dna_type = ex.args
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struct_index = self.file.sdna_index_from_id.get(dna_type.dna_type_id, None)
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if struct_index is None:
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yield (path_full, "<%s>" % dna_type.dna_type_id.decode("ascii"))
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else:
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struct = self.file.structs[struct_index]
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for f in struct.fields:
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yield from self.get_recursive_iter(
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f.dna_name.name_only,
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path_full,
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default,
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None,
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use_nil,
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use_str,
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0,
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)
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def items_recursive_iter(self):
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for k in self.keys():
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yield from self.get_recursive_iter(k, use_str=False)
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def get_data_hash(self):
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"""
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Generates a 'hash' that can be used instead of addr_old as block id, and that should be 'stable' across .blend
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file load & save (i.e. it does not changes due to pointer addresses variations).
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"""
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# TODO This implementation is most likely far from optimal... and CRC32 is not renown as the best hashing
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# algo either. But for now does the job!
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import zlib
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def _is_pointer(self, k):
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return (
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self.file.structs[self.sdna_index]
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.field_from_path(self.file.header, self.file.handle, k)
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.dna_name.is_pointer
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)
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hsh = 1
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for k, v in self.items_recursive_iter():
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if not _is_pointer(self, k):
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hsh = zlib.adler32(str(v).encode(), hsh)
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return hsh
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|
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def set(
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self,
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path,
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value,
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sdna_index_refine=None,
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):
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if sdna_index_refine is None:
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sdna_index_refine = self.sdna_index
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else:
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self.file.ensure_subtype_smaller(self.sdna_index, sdna_index_refine)
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dna_struct = self.file.structs[sdna_index_refine]
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self.file.handle.seek(self.file_offset, os.SEEK_SET)
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self.file.is_modified = True
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return dna_struct.field_set(self.file.header, self.file.handle, path, value)
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|
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# ---------------
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|
# Utility get/set
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|
#
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|
# avoid inline pointer casting
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|
def get_pointer(
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self,
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path,
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default=...,
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sdna_index_refine=None,
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|
base_index=0,
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):
|
|
if sdna_index_refine is None:
|
|
sdna_index_refine = self.sdna_index
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result = self.get(
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|
path, default, sdna_index_refine=sdna_index_refine, base_index=base_index
|
|
)
|
|
|
|
# default
|
|
if type(result) is not int:
|
|
return result
|
|
|
|
assert (
|
|
self.file.structs[sdna_index_refine]
|
|
.field_from_path(self.file.header, self.file.handle, path)
|
|
.dna_name.is_pointer
|
|
)
|
|
if result != 0:
|
|
# possible (but unlikely)
|
|
# that this fails and returns None
|
|
# maybe we want to raise some exception in this case
|
|
return self.file.find_block_from_offset(result)
|
|
else:
|
|
return None
|
|
|
|
# ----------------------
|
|
# Python convenience API
|
|
|
|
# dict like access
|
|
def __getitem__(self, item):
|
|
return self.get(item, use_str=False)
|
|
|
|
def __setitem__(self, item, value):
|
|
self.set(item, value)
|
|
|
|
def keys(self):
|
|
return (f.dna_name.name_only for f in self.dna_type.fields)
|
|
|
|
def values(self):
|
|
for k in self.keys():
|
|
try:
|
|
yield self[k]
|
|
except NotImplementedError as ex:
|
|
msg, dna_name, dna_type = ex.args
|
|
yield "<%s>" % dna_type.dna_type_id.decode("ascii")
|
|
|
|
def items(self):
|
|
for k in self.keys():
|
|
try:
|
|
yield (k, self[k])
|
|
except NotImplementedError as ex:
|
|
msg, dna_name, dna_type = ex.args
|
|
yield (k, "<%s>" % dna_type.dna_type_id.decode("ascii"))
|
|
|
|
|
|
# -----------------------------------------------------------------------------
|
|
# Read Magic
|
|
#
|
|
# magic = str
|
|
# pointer_size = int
|
|
# is_little_endian = bool
|
|
# version = int
|
|
|
|
|
|
class BlendFileHeader:
|
|
"""
|
|
BlendFileHeader allocates the first 12 bytes of a blend file
|
|
it contains information about the hardware architecture
|
|
"""
|
|
|
|
__slots__ = (
|
|
# str
|
|
"magic",
|
|
# int 4/8
|
|
"pointer_size",
|
|
# bool
|
|
"is_little_endian",
|
|
# int
|
|
"version",
|
|
# str, used to pass to 'struct'
|
|
"endian_str",
|
|
# int, used to index common types
|
|
"endian_index",
|
|
)
|
|
|
|
def __init__(self, handle):
|
|
FILEHEADER = struct.Struct(b"7s1s1s3s")
|
|
|
|
log.debug("reading blend-file-header")
|
|
values = FILEHEADER.unpack(handle.read(FILEHEADER.size))
|
|
self.magic = values[0]
|
|
pointer_size_id = values[1]
|
|
if pointer_size_id == b"-":
|
|
self.pointer_size = 8
|
|
elif pointer_size_id == b"_":
|
|
self.pointer_size = 4
|
|
else:
|
|
assert 0
|
|
endian_id = values[2]
|
|
if endian_id == b"v":
|
|
self.is_little_endian = True
|
|
self.endian_str = b"<"
|
|
self.endian_index = 0
|
|
elif endian_id == b"V":
|
|
self.is_little_endian = False
|
|
self.endian_index = 1
|
|
self.endian_str = b">"
|
|
else:
|
|
assert 0
|
|
|
|
version_id = values[3]
|
|
self.version = int(version_id)
|
|
|
|
def create_block_header_struct(self):
|
|
return struct.Struct(
|
|
b"".join(
|
|
(
|
|
self.endian_str,
|
|
b"4sI",
|
|
b"I" if self.pointer_size == 4 else b"Q",
|
|
b"II",
|
|
)
|
|
)
|
|
)
|
|
|
|
|
|
class DNAName:
|
|
"""
|
|
DNAName is a C-type name stored in the DNA
|
|
"""
|
|
|
|
__slots__ = (
|
|
"name_full",
|
|
"name_only",
|
|
"is_pointer",
|
|
"is_method_pointer",
|
|
"array_size",
|
|
)
|
|
|
|
def __init__(self, name_full):
|
|
self.name_full = name_full
|
|
self.name_only = self.calc_name_only()
|
|
self.is_pointer = self.calc_is_pointer()
|
|
self.is_method_pointer = self.calc_is_method_pointer()
|
|
self.array_size = self.calc_array_size()
|
|
|
|
def __repr__(self):
|
|
return "%s(%r)" % (type(self).__qualname__, self.name_full)
|
|
|
|
def as_reference(self, parent):
|
|
if parent is None:
|
|
result = b""
|
|
else:
|
|
result = parent + b"."
|
|
|
|
result = result + self.name_only
|
|
return result
|
|
|
|
def calc_name_only(self):
|
|
result = self.name_full.strip(b"*()")
|
|
index = result.find(b"[")
|
|
if index != -1:
|
|
result = result[:index]
|
|
return result
|
|
|
|
def calc_is_pointer(self):
|
|
return b"*" in self.name_full
|
|
|
|
def calc_is_method_pointer(self):
|
|
return b"(*" in self.name_full
|
|
|
|
def calc_array_size(self):
|
|
result = 1
|
|
temp = self.name_full
|
|
index = temp.find(b"[")
|
|
|
|
while index != -1:
|
|
index_2 = temp.find(b"]")
|
|
result *= int(temp[index + 1 : index_2])
|
|
temp = temp[index_2 + 1 :]
|
|
index = temp.find(b"[")
|
|
|
|
return result
|
|
|
|
|
|
class DNAField:
|
|
"""
|
|
DNAField is a coupled DNAStruct and DNAName
|
|
and cache offset for reuse
|
|
"""
|
|
|
|
__slots__ = (
|
|
# DNAName
|
|
"dna_name",
|
|
# tuple of 3 items
|
|
# [bytes (struct name), int (struct size), DNAStruct]
|
|
"dna_type",
|
|
# size on-disk
|
|
"dna_size",
|
|
# cached info (avoid looping over fields each time)
|
|
"dna_offset",
|
|
)
|
|
|
|
def __init__(self, dna_type, dna_name, dna_size, dna_offset):
|
|
self.dna_type = dna_type
|
|
self.dna_name = dna_name
|
|
self.dna_size = dna_size
|
|
self.dna_offset = dna_offset
|
|
|
|
|
|
class DNAStruct:
|
|
"""
|
|
DNAStruct is a C-type structure stored in the DNA
|
|
"""
|
|
|
|
__slots__ = (
|
|
"dna_type_id",
|
|
"size",
|
|
"fields",
|
|
"field_from_name",
|
|
"user_data",
|
|
)
|
|
|
|
def __init__(self, dna_type_id):
|
|
self.dna_type_id = dna_type_id
|
|
self.fields = []
|
|
self.field_from_name = {}
|
|
self.user_data = None
|
|
|
|
def __repr__(self):
|
|
return "%s(%r)" % (type(self).__qualname__, self.dna_type_id)
|
|
|
|
def field_from_path(self, header, handle, path):
|
|
"""
|
|
Support lookups as bytes or a tuple of bytes and optional index.
|
|
|
|
C style 'id.name' --> (b'id', b'name')
|
|
C style 'array[4]' --> ('array', 4)
|
|
"""
|
|
if type(path) is tuple:
|
|
name = path[0]
|
|
if len(path) >= 2 and type(path[1]) is not bytes:
|
|
name_tail = path[2:]
|
|
index = path[1]
|
|
assert type(index) is int
|
|
else:
|
|
name_tail = path[1:]
|
|
index = 0
|
|
else:
|
|
name = path
|
|
name_tail = None
|
|
index = 0
|
|
|
|
assert type(name) is bytes
|
|
|
|
field = self.field_from_name.get(name)
|
|
|
|
if field is not None:
|
|
handle.seek(field.dna_offset, os.SEEK_CUR)
|
|
if index != 0:
|
|
if field.dna_name.is_pointer:
|
|
index_offset = header.pointer_size * index
|
|
else:
|
|
index_offset = field.dna_type.size * index
|
|
assert index_offset < field.dna_size
|
|
handle.seek(index_offset, os.SEEK_CUR)
|
|
if not name_tail: # None or ()
|
|
return field
|
|
else:
|
|
return field.dna_type.field_from_path(header, handle, name_tail)
|
|
|
|
def field_get(
|
|
self,
|
|
header,
|
|
handle,
|
|
path,
|
|
default=...,
|
|
use_nil=True,
|
|
use_str=True,
|
|
):
|
|
field = self.field_from_path(header, handle, path)
|
|
if field is None:
|
|
if default is not ...:
|
|
return default
|
|
else:
|
|
raise KeyError(
|
|
"%r not found in %r (%r)"
|
|
% (
|
|
path,
|
|
[f.dna_name.name_only for f in self.fields],
|
|
self.dna_type_id,
|
|
)
|
|
)
|
|
|
|
dna_type = field.dna_type
|
|
dna_name = field.dna_name
|
|
|
|
if dna_name.is_pointer:
|
|
return DNA_IO.read_pointer(handle, header)
|
|
elif dna_type.dna_type_id == b"int":
|
|
if dna_name.array_size > 1:
|
|
return [
|
|
DNA_IO.read_int(handle, header) for i in range(dna_name.array_size)
|
|
]
|
|
return DNA_IO.read_int(handle, header)
|
|
elif dna_type.dna_type_id == b"short":
|
|
if dna_name.array_size > 1:
|
|
return [
|
|
DNA_IO.read_short(handle, header)
|
|
for i in range(dna_name.array_size)
|
|
]
|
|
return DNA_IO.read_short(handle, header)
|
|
elif dna_type.dna_type_id == b"uint64_t":
|
|
if dna_name.array_size > 1:
|
|
return [
|
|
DNA_IO.read_ulong(handle, header)
|
|
for i in range(dna_name.array_size)
|
|
]
|
|
return DNA_IO.read_ulong(handle, header)
|
|
elif dna_type.dna_type_id == b"float":
|
|
if dna_name.array_size > 1:
|
|
return [
|
|
DNA_IO.read_float(handle, header)
|
|
for i in range(dna_name.array_size)
|
|
]
|
|
return DNA_IO.read_float(handle, header)
|
|
elif dna_type.dna_type_id == b"char":
|
|
if use_str:
|
|
if use_nil:
|
|
return DNA_IO.read_string0(handle, dna_name.array_size)
|
|
else:
|
|
return DNA_IO.read_string(handle, dna_name.array_size)
|
|
else:
|
|
if use_nil:
|
|
return DNA_IO.read_bytes0(handle, dna_name.array_size)
|
|
else:
|
|
return DNA_IO.read_bytes(handle, dna_name.array_size)
|
|
else:
|
|
raise NotImplementedError(
|
|
"%r exists but isn't pointer, can't resolve field %r"
|
|
% (path, dna_name.name_only),
|
|
dna_name,
|
|
dna_type,
|
|
)
|
|
|
|
def field_set(self, header, handle, path, value):
|
|
assert type(path) == bytes
|
|
|
|
field = self.field_from_path(header, handle, path)
|
|
if field is None:
|
|
raise KeyError(
|
|
"%r not found in %r"
|
|
% (path, [f.dna_name.name_only for f in self.fields])
|
|
)
|
|
|
|
dna_type = field.dna_type
|
|
dna_name = field.dna_name
|
|
|
|
if dna_type.dna_type_id == b"char":
|
|
if type(value) is str:
|
|
return DNA_IO.write_string(handle, value, dna_name.array_size)
|
|
else:
|
|
return DNA_IO.write_bytes(handle, value, dna_name.array_size)
|
|
elif dna_type.dna_type_id == b"int":
|
|
DNA_IO.write_int(handle, header, value)
|
|
else:
|
|
raise NotImplementedError(
|
|
"Setting %r is not yet supported for %r" % (dna_type, dna_name),
|
|
dna_name,
|
|
dna_type,
|
|
)
|
|
|
|
|
|
class DNA_IO:
|
|
"""
|
|
Module like class, for read-write utility functions.
|
|
|
|
Only stores static methods & constants.
|
|
"""
|
|
|
|
__slots__ = ()
|
|
|
|
def __new__(cls, *args, **kwargs):
|
|
raise RuntimeError("%s should not be instantiated" % cls)
|
|
|
|
@staticmethod
|
|
def write_string(handle, astring, fieldlen):
|
|
assert isinstance(astring, str)
|
|
if len(astring) >= fieldlen:
|
|
stringw = astring[0:fieldlen]
|
|
else:
|
|
stringw = astring + "\0"
|
|
handle.write(stringw.encode("utf-8"))
|
|
|
|
@staticmethod
|
|
def write_bytes(handle, astring, fieldlen):
|
|
assert isinstance(astring, (bytes, bytearray))
|
|
if len(astring) >= fieldlen:
|
|
stringw = astring[0:fieldlen]
|
|
else:
|
|
stringw = astring + b"\0"
|
|
|
|
handle.write(stringw)
|
|
|
|
@staticmethod
|
|
def read_bytes(handle, length):
|
|
data = handle.read(length)
|
|
return data
|
|
|
|
@staticmethod
|
|
def read_bytes0(handle, length):
|
|
data = handle.read(length)
|
|
return DNA_IO.read_data0(data)
|
|
|
|
@staticmethod
|
|
def read_string(handle, length):
|
|
return DNA_IO.read_bytes(handle, length).decode("utf-8")
|
|
|
|
@staticmethod
|
|
def read_string0(handle, length):
|
|
return DNA_IO.read_bytes0(handle, length).decode("utf-8")
|
|
|
|
@staticmethod
|
|
def read_data0_offset(data, offset):
|
|
add = data.find(b"\0", offset) - offset
|
|
return data[offset : offset + add]
|
|
|
|
@staticmethod
|
|
def read_data0(data):
|
|
add = data.find(b"\0")
|
|
return data[:add]
|
|
|
|
USHORT = struct.Struct(b"<H"), struct.Struct(b">H")
|
|
|
|
@staticmethod
|
|
def read_ushort(handle, fileheader):
|
|
st = DNA_IO.USHORT[fileheader.endian_index]
|
|
return st.unpack(handle.read(st.size))[0]
|
|
|
|
SSHORT = struct.Struct(b"<h"), struct.Struct(b">h")
|
|
|
|
@staticmethod
|
|
def read_short(handle, fileheader):
|
|
st = DNA_IO.SSHORT[fileheader.endian_index]
|
|
return st.unpack(handle.read(st.size))[0]
|
|
|
|
UINT = struct.Struct(b"<I"), struct.Struct(b">I")
|
|
|
|
@staticmethod
|
|
def read_uint(handle, fileheader):
|
|
st = DNA_IO.UINT[fileheader.endian_index]
|
|
return st.unpack(handle.read(st.size))[0]
|
|
|
|
SINT = struct.Struct(b"<i"), struct.Struct(b">i")
|
|
|
|
@staticmethod
|
|
def read_int(handle, fileheader):
|
|
st = DNA_IO.SINT[fileheader.endian_index]
|
|
return st.unpack(handle.read(st.size))[0]
|
|
|
|
@staticmethod
|
|
def write_int(handle, fileheader, value):
|
|
assert isinstance(value, int), "value must be int, but is %r: %r" % (
|
|
type(value),
|
|
value,
|
|
)
|
|
st = DNA_IO.SINT[fileheader.endian_index]
|
|
to_write = st.pack(value)
|
|
handle.write(to_write)
|
|
|
|
FLOAT = struct.Struct(b"<f"), struct.Struct(b">f")
|
|
|
|
@staticmethod
|
|
def read_float(handle, fileheader):
|
|
st = DNA_IO.FLOAT[fileheader.endian_index]
|
|
return st.unpack(handle.read(st.size))[0]
|
|
|
|
ULONG = struct.Struct(b"<Q"), struct.Struct(b">Q")
|
|
|
|
@staticmethod
|
|
def read_ulong(handle, fileheader):
|
|
st = DNA_IO.ULONG[fileheader.endian_index]
|
|
return st.unpack(handle.read(st.size))[0]
|
|
|
|
@staticmethod
|
|
def read_pointer(handle, header):
|
|
"""
|
|
reads an pointer from a file handle
|
|
the pointer size is given by the header (BlendFileHeader)
|
|
"""
|
|
if header.pointer_size == 4:
|
|
st = DNA_IO.UINT[header.endian_index]
|
|
return st.unpack(handle.read(st.size))[0]
|
|
if header.pointer_size == 8:
|
|
st = DNA_IO.ULONG[header.endian_index]
|
|
return st.unpack(handle.read(st.size))[0]
|