diff options
Diffstat (limited to 'release/scripts/modules/blend_render_info.py')
-rwxr-xr-x | release/scripts/modules/blend_render_info.py | 114 |
1 files changed, 80 insertions, 34 deletions
diff --git a/release/scripts/modules/blend_render_info.py b/release/scripts/modules/blend_render_info.py index 461ea877383..4ba818a19e5 100755 --- a/release/scripts/modules/blend_render_info.py +++ b/release/scripts/modules/blend_render_info.py @@ -12,24 +12,65 @@ # int SDNAnr, nr; # } BHead; +__all__ = ( + "read_blend_rend_chunk", +) + + +class RawBlendFileReader: + """ + Return a file handle to the raw blend file data (abstracting compressed formats). + """ + __slots__ = ( + # The path to load. + "_filepath", + # The file base file handler or None (only set for compressed formats). + "_blendfile_base", + # The file handler to return to the caller (always uncompressed data). + "_blendfile", + ) + + def __init__(self, filepath): + self._filepath = filepath + self._blendfile_base = None + self._blendfile = None + + def __enter__(self): + blendfile = open(self._filepath, "rb") + blendfile_base = None + head = blendfile.read(4) + blendfile.seek(0) + if head[0:2] == b'\x1f\x8b': # GZIP magic. + import gzip + blendfile_base = blendfile + blendfile = gzip.open(blendfile, "rb") + elif head[0:4] == b'\x28\xb5\x2f\xfd': # Z-standard magic. + import zstandard + blendfile_base = blendfile + blendfile = zstandard.open(blendfile, "rb") -def read_blend_rend_chunk(path): + self._blendfile_base = blendfile_base + self._blendfile = blendfile - import struct + return self._blendfile - blendfile = open(path, "rb") + def __exit__(self, exc_type, exc_value, exc_traceback): + self._blendfile.close() + if self._blendfile_base is not None: + self._blendfile_base.close() - head = blendfile.read(7) + return False - if head[0:2] == b'\x1f\x8b': # gzip magic - import gzip - blendfile.seek(0) - blendfile = gzip.open(blendfile, "rb") - head = blendfile.read(7) +def _read_blend_rend_chunk_from_file(blendfile, filepath): + import struct + import sys + + from os import SEEK_CUR + + head = blendfile.read(7) if head != b'BLENDER': - print("not a blend file:", path) - blendfile.close() + sys.stderr.write("Not a blend file: %s\n" % filepath) return [] is_64_bit = (blendfile.read(1) == b'-') @@ -37,47 +78,52 @@ def read_blend_rend_chunk(path): # true for PPC, false for X86 is_big_endian = (blendfile.read(1) == b'V') - # Now read the bhead chunk!!! - blendfile.read(3) # skip the version + # Now read the bhead chunk! + blendfile.seek(3, SEEK_CUR) # Skip the version. scenes = [] sizeof_bhead = 24 if is_64_bit else 20 - while blendfile.read(4) == b'REND': - sizeof_bhead_left = sizeof_bhead - 4 + while len(bhead_id := blendfile.read(4)) == 4: + sizeof_data_left = struct.unpack('>i' if is_big_endian else '<i', blendfile.read(4))[0] + # 4 from the `head_id`, another 4 for the size of the BHEAD. + sizeof_bhead_left = sizeof_bhead - 8 - struct.unpack('>i' if is_big_endian else '<i', blendfile.read(4))[0] - sizeof_bhead_left -= 4 + # The remainder of the BHEAD struct is not used. + blendfile.seek(sizeof_bhead_left, SEEK_CUR) - # We don't care about the rest of the bhead struct - blendfile.read(sizeof_bhead_left) + if bhead_id == b'REND': + # Now we want the scene name, start and end frame. this is 32bits long. + start_frame, end_frame = struct.unpack('>2i' if is_big_endian else '<2i', blendfile.read(8)) + sizeof_data_left -= 8 - # Now we want the scene name, start and end frame. this is 32bites long - start_frame, end_frame = struct.unpack('>2i' if is_big_endian else '<2i', blendfile.read(8)) + scene_name = blendfile.read(64) + sizeof_data_left -= 64 - scene_name = blendfile.read(64) + scene_name = scene_name[:scene_name.index(b'\0')] + # It's possible old blend files are not UTF8 compliant, use `surrogateescape`. + scene_name = scene_name.decode("utf8", errors='surrogateescape') - scene_name = scene_name[:scene_name.index(b'\0')] + scenes.append((start_frame, end_frame, scene_name)) - try: - scene_name = str(scene_name, "utf8") - except TypeError: - pass + if sizeof_data_left != 0: + blendfile.seek(sizeof_data_left, SEEK_CUR) - scenes.append((start_frame, end_frame, scene_name)) + return scenes - blendfile.close() - return scenes +def read_blend_rend_chunk(filepath): + with RawBlendFileReader(filepath) as blendfile: + return _read_blend_rend_chunk_from_file(blendfile, filepath) def main(): import sys - for arg in sys.argv[1:]: - if arg.lower().endswith('.blend'): - for value in read_blend_rend_chunk(arg): - print("%d %d %s" % value) + + for filepath in sys.argv[1:]: + for value in read_blend_rend_chunk(filepath): + print("%d %d %s" % value) if __name__ == '__main__': |