Loading Python file in SofaUnity

[BinhTran17]

Hi, I have a simulation in SOFA framework, and I want to put it in Unity. I have 2 files, one .scn and one .py, and 2 corresponding .msh files, all put in this GDrive folder. The files work well in SOFA 24.12.00 but I can't get the Python one to work in Unity.

• I have tried a couple of combinations of Unity versions (2022.3 and 6.2) and SofaUnity versions (24.12, 25.06, and from Unity Assets store)
• The Assets store version uses 24.12.00 DLLs.
• My laptop is running Windows 11.
• Python and required packages versions: Python 3.12.1, numpy 2.3.5, scipy 1.16.3, and pybind11 2.12.0.
• I tested on 4 demo scenes: Demo_01_LiverInteraction and Demo_02_LiverInteraction-HD from Interaction folder, and LiverPyhon and LiverPyhonController from Python folder

Following are my findings

Unity Version	24.12.00	25.06.00	Assets store (24.12.00)
2022.3.62f2	Cannot load .py files, only shows DefaultVisualManagerLoop and DefaultAnimationLoop when load. Demo_01 and Demo_02 of interaction don't have lighting. Python demo scenes don't move or interact. [Ref A]	Python demo scenes show nothing by default, SofaContext only include DefaultVisualManagerLoop, DefaultAnimationLoop, and SofaCollisionPipeline. Loading .py files yield same problem as SOFA 24.12.00. [Ref B]	Similar to SOFA 24.12.00, but a texture loading error makes everything pink. Cannot see the animation. [Ref C]
6000.2.6f2	Cannot load either .scn or .py files, the Scene Filename field doesn't change.	Same as above	Same as above

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Screenshot References

• [Ref A] -
• [Ref B] -
• [Ref C] -

[epernod]

Hi,

we are working on bringing back the python support. It should be fixed as soon as the PR #222 and it's dependencies in SOFA are merged.
We will make sure this is part of the next release v25.12 which should be available by the end of the month.

Best regards

[epernod]

Hi @BinhTran17 ,

could you test the last version v25.12: https://github.com/InfinyTech3D/SofaUnity/releases/tag/SofaUnity_v25.12.00-URP
The Python integration has normally been fixed in this last version.

Best regards,

[BinhTran17]

Hi @epernod, thank you for your reply. Unfortunately, there is a new problem.
At first, the SofaPython3.dll wouldn't load, and I found out that it was because v25.12 uses Python 3.13 instead of 3.12 as instructed in the SofaPython3 Install page. Then, I installed Python 3.13, still keeping 3.12, and the whole Unity project just shut down when I tried loading SofaPython3.dll.
My other projects running v25.06 are still fine. Do you know what might have caused this behaviour?
Thank you.

[epernod]

Hi could you check this issue and let us know if it solves your problem:

#255 (comment)

[azizsnd]

Hi @epernod , I'm hitting the exact same issue as @BinhTran17 on v25.12 with Python 3.13.
Applied the flush fix from #255. Also added os.add_dll_directory() for the Native/x64 folder. Disabled SofaImGui/SofaGLFW/Sofa.Gui to avoid OpenGL context conflicts. Unity still shuts down silently when SofaPython3.dll loads — no crash dump, no Python init messages in Editor.log. XML scenes work perfectly.
Is there any known workaround?