[BUILD] Can't import pyopenvdb in Windows 10

[diegogangl]

Environment

Operating System: Windows 10 / Python 3.9
Version / Commit SHA: VDB 8.0.1
CMake Version: 3.20.4
Compiler: msvc 2019

Describe the problem

The Python module builds but can't be imported, as it fails to load some DLL

To Reproduce

1. Build OpenVDB with the Python module option.
2. Open a powershell or regular prompt at the folder where the pyd file is
3. Try to import pyopenvdb

Tried

• Copying DLLs into the folder (Half-2_5.dll, libzstd.dll, openvdb.dll and boost_python39-vc142-mt-gd-x64-1_76.dll). I got these from the Dependencies tool.
• Also tried adding snappy_64.dll
• Appending the path to sys.path
• Adding the path with os.add_dll_directory()
• Look around the source code to figure out which dll is trying to find

No matter what I try I always get

>>> import pyopenvdb
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: DLL load failed while importing pyopenvdb: The specified module could not be found.

I need to distribute the python module along with a project, so it needs to be portable (at least not require users to compile things). Is it possible to at least know which DLL is missing or where it's looking for it?

[diiigle]

Hi Diego,

There is the new discussions forum for questions right here on github.

To answer your question:
I would start with dependencywalker as this lists you all the recursively missing DLLs. I would suspect boost_python might also depend on other boost libraries.

[diegogangl]

Thanks @diiigle , I'll open a discussion over there.

[Idclip]

Hi @diegogangl,

How are you installing VDB dependencies (boost, tbb etc), are you using vcpkg? Can you also double check that the version of python you're launching is exactly the same as the version VDB has been compiled against (i.e. 3.9)?

edit: Here's how I'm testing on Windows: #946 (comment)

[Idclip]

Closing, but please re-open if this is still an issue