doesn't work in latest unreal

[hannesdelbeke]

latest unreal uses pyside6, Qt.py doesnt support this yet.
another wrapper qtpy, would work.
but pyside6 released a bug in their latest release, which also breaks with qtpy. no good solution available atm.

more details here plugget/plugget-unreal-plugin#14

there are 2 problems:

• no PySide6 support
  • wait untill Qt.py has PySide 6 support. might be a long time.
  • or swap to qtpy instead of Qt.py
• PySide 6 bug
  • wait for the next PySide6 release. could be months or year (clean but slow)
  • try a workaround by manually importing from PySide6 in specific way. messy and annoying approach, time consumiong dev time

[munkybutt]

I have tried to get this to work with unreal 5.4, using PySide6 6.7.2 and qtpy.
Unreal hangs when trying to run _loadUi. Debugging leads to QUiLoader.__init__(self, baseinstance) in UiLoader.

I will try roll back to earlier versions of PySide6 and see if that works around the issue

[hannesdelbeke]

- Can you also try an older version of unreal? i haven't tried 5.4 yet. Maybe it needs some updates. - I believe pyside 6 released an update to address the bug in their release mentioned in a previous reply. - Qt.py released an update to support Pyside6

…

On Thu, Jul 4, 2024, 10:10 AM Shea Richardson ***@***.***> wrote: I have tried to get this to work with unreal 5.4, using PySide6 6.7.2 and qtpy. Unreal hangs when trying to run _loadUi. Debugging leads to QUiLoader.__init__(self, baseinstance) in UiLoader. I will try roll back to earlier versions of PySide6 and see if that works around the issue — Reply to this email directly, view it on GitHub <#10 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AA4VRZCPY753W5KKU3E25XTZKUGRXAVCNFSM6AAAAABKLD7XZ6VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDEMBYGQ4DONZVGU> . You are receiving this because you authored the thread.Message ID: ***@***.***>

[munkybutt]

We aren't using Qt.py in our code base anymore, they kind of missed the boat with Qt6 support so we moved on, changing back to Qt.py will be a big undertaking.

The crash happens when PySide6 calls QUiLoader.__init__ which is calling the underlying c++ so not something that could be fixed on the python side I don't think :/

I will see if unreal 5.3 works if I get a chance.

For now rolling back to earlier versions of PySide6 to see any work.

Also grumbling a lot about why people use ui files for production tools instead of just writing code 😭

[munkybutt]

6.6 still hangs
6.5 crashes unreal on startup
6.4 same

Installed Qt.py alongside qtpy and hang still occurs with 6.7 + 6.6.
There must be some issue with Unreal 5.4 + Python 3.11 + PySide6 QUiLoader 😖

[hannesdelbeke]

i think there is a similar loadUI issue with Blender and PySide6 techartorg/bqt#124

[hannesdelbeke]

possible related issue from 2017 with PySide and Qt.py mottosso/Qt.py#208

[hannesdelbeke]

tried using qtpy instead of Qt.py, still freezes Unreal

[munkybutt]

Yeah that makes sense - the error happens on the c++ side. Might be worth raising a bug with Qt/Pyside? The only other way I thought to be able to debug it was compile PySide6 myself to be able to follow the call stack into c++. Not had time to fight that battle though

[hannesdelbeke]

i managed to launch it without crashing, when I created py files from the ui file with the command

pyside6-uic "D:\Unreal Projects\blueprint\Content\Python\Lib\site-packages\unreal_script_editor\ui\output_text_widget.ui" -o "D:\Unreal Projects\blueprint\Content\Python\Lib\site-packages\unreal_script_editor\ui\output_text_widget.py"
pyside6-uic "D:\Unreal Projects\blueprint\Content\Python\Lib\site-packages\unreal_script_editor\ui\script_editor.ui" -o "D:\Unreal Projects\blueprint\Content\Python\Lib\site-packages\unreal_script_editor\ui\script_editor.py"

however it seems i need to edit / update some code too, which is still WIP.