---
The blendfile module within BAT supports reading data from structs, such
as the Count property on an array modifier. However, blendfile only
supports modifying structs with type "char". This patch adds support for
writing structs of more types in blendfile blocks. Now, writing is
supported for ushort, short, uint, int, float, and ulong types.
The use case that inspired this patch was an instance where a file had
several array modifiers that prevented the file from being opened in
Blender on machines without large amounts of RAM. A solution using the
blendfile module may look like:
```
from blender_asset_tracer import blendfile
from pathlib import Path
b = blendfile.open_cached(Path('flag.blend'), mode='rb+')
for block in b.blocks:
if 'ArrayModifierData' in block.__str__():
try:
print('previous:', block.get(b'count'))
block.set(b'count', 1)
print('current:', block.get(b'count'))
except KeyError:
continue
b.close()
```
This would fail with the exception
`blender_asset_tracer.blendfile.exceptions.NoWriterImplemented: Setting
type Struct(b'int') is not supported for ArrayModifierData.count`. With
this patch, the above code succeeds and the count struct can be set to
a lower number that allows the file to be opened.
This solution implements missing functionality without adding any new
interfaces. A few details are:
* When deciding what type to write to the struct, the value is inferred
from what is given by the caller. If the caller gives a Python int, the
exact type is inferred from the DNA type ID. If they give a float, a
float is written. Otherwise, the existing logic is used to determine
whether to write a string or byte sequence.
* A \_write method was added to dna\_io.py that takes a Python struct
object and a value to write a byte sequence to the file object. This
method is used by public methods appropriately named to indicate what
type they will write.
* The check for whether the caller is trying to write an unsupported
type is left in place, but it has been changed to include types which
are now supported.
* Tests have been added that provide a mock file object, call the new
methods, and confirm that the correct bytes were written.
Reviewed By: sybren
Differential Revision: https://developer.blender.org/D14374
Decided to *not* support the Shaman API of Flamenco 3.x in BAT. The
support for that protocol will be implemented in the Flamenco 3.x add-on
for Blender, and not in BAT itself.
A future version of BAT will remove the Shaman API support altogether.
Avoiding late imports helps to isolate Blender add-ons bundling BAT from
each other.
There was one late/lazy import to avoid a dependency cycle. This was
solved by simply copying that one tiny function.
File permissions are no longer copied when packing. This means that
read-only source files can still be packed without errors, even when
they have to be rewritten (due to changed paths).
Reviewed by: sybren
Differential Revision: https://developer.blender.org/D13128
BAT now can take advantage of the `zstandard` module to handle Blender
3.0+ compressed blend files.
If the module is not installed, the blend files cannot be opened but
GZip-compressed and uncompressed files can still be handled.
Add support for linked collections that are used as input in a Geometry
Nodes modifier. This requires iterating over the geometry nodes modifier
settings, which consists of ID properties. If such an ID property is of
type `IDP_ID`, its pointer is followed and the pointed-to datablock +
its library are visited.
This following of pointers happens in the 'expand' phase, which was only
done for linked library blend files. Since this commit, the old
behaviour of simply looping over all non-`DATA` datablocks of the
to-be-packed blend file is not enough, and datablock expansion is done
for all local datablocks as well.
Due to issues with library overrides and unsynced pointers, it's quite
common for the Blender Animation Studio to get crashes of BAT. To avoid
these, Strict Pointer Mode is disabled when using BAT from the CLI.
Blender Cloud add-on will also get a similar update, so that there also
the Strict Pointer Mode is disabled.
Add a 'strict pointer mode' to the `BlendFile` class, which is enabled
by default. This allows users of the `BlendFile` class to decide whether
a bad pointer (i.e. one that points to a non-existing datablock) returns
`None` or raises a `SegmentationFault` exception.
Remove an assertion that would cause BAT to raise and exception and halt
when a library blend file is missing. This assertion was fine for aiding
the coding of the library, but now gets in the way of tracing dependencies
of partially checked-out projects.
This commit fixes a bunch of issues at the same time, as they are all
related to path handling:
- `pathlib.Path.resolve()` or `.absolute()` are replaced by
`bpathlib.make_absolute()`. The latter does NOT follow symlinks and does
NOT network mounts from a drive letter to UNC notation. This also has
advantages on non-Windows sytems, as it allows BAT-packing a directory
structure with symlinked files (such as a Shaman checkout).
- Better handling of drive letters, and of paths that cross drive
boundaries.
- Better testing of Windows-specific cases when running the tests on
Windows, and of POSIX-specific cases on other platforms.
Thanks to @wisaac for starting this patch in D6676.
Thanks to @jbakker for pointing out the drive letter issue. This fixes
T70655.
This may also fix a Windows compatibility issue related to path
normalisation. Untested as it's hard to reproduce, but at least it
shouldn't hurt either.
External files with the same path on different drives are packed as a
single file. In this commit the drive letter is taken into account when
determining the path inside `_outside_project`, so that they are distinct.
