This adds a debugging utility for developers that makes it easier to what's
stored in a .blend file. Some possible use cases:
* Figure out if some specific data has been written to the .blend file.
* Check the order of data in the .blend file.
* Work towards having less runtime dependent changes in .blend files (it's
easier to diff the textual output).
It is **not** a goal to provide a general human and machine readable form of
.blend files (like xml/json files). That would be way more involved.
The way to use this is to set `GENERATE_DEBUG_BLEND_FILE` to `1` at the top of
`writefile.cc`. Then, whenever Blender saves a .blend file, it will generate a
`.debug.txt` file next to it.
There is already `blend2json.py` which serves a similar purpose but is a
separate program that can be executed on the .blend file afterwards. With the
`--full-data` flag it outputs comparable data, but the output is a bit more
verbose and it needs an extra step that can be avoided by generating the
`.debug.txt` file immediately. For certain use cases,
`GENERATE_DEBUG_BLEND_FILE` can be more convenient. It's also much simpler to
add log additional data in that file that is produced during the blend-write
process.
Pull Request: https://projects.blender.org/blender/blender/pulls/133063