[BUG FIX] ext/pyrender/viewer: resolve macOS crashes when initialising Tk()

[NekoAsakura]

This PR should resolve Issue#91.
On macOS, a Tk instance should be initiated before creating the viewer.

[NekoAsakura]

The purpose of this code is to ensure compatibility with Tkinter, supporting both Python 2 and Python 3. Genesis requires Python 3.9 or higher, such compatibility adjustments are unnecessary.

Genesis/pyproject.toml

Line 12 in 2985aa9

requires-python = ">=3.9"

[NekoAsakura]

Hide root window as we only use filedialog to save image.

[zhouxian]

Thank you for this!!!! Could you test and make sure it doesn't interfere with other os? if not we can merge

[NekoAsakura]

I have tested viewer on macOS 15.2 and Ubuntu 22.04 w/ cu118, and it worked as expected. It should also function correctly on Windows, but I don't have a testing platform to confirm this.

To test it, run any script containing genesis.Scene(...).viewer.start(). When viewer window appears, press "s" to save an image.

The use of root.withdraw() can also be found in CPython:
https://github.com/python/cpython/blob/09d15aa9a87f69867e69f00d0e9671d70a4a49c5/Lib/tkinter/__init__.py#L329-L343

So I assume it works well across multiple platforms.

[zhouxian]

@zhenjia-xu could you take care of this?

[NekoAsakura]

@zhouxian I have made a test on Windows 10 22H2 19045.5247 and it was passed. I believe it's safe to merge, and it shouldn't cause any issues with other supporting os.

[zhouxian]

Thank you:)

[zhouxian]

Hi, it seems this caused issue on linux via SSH, and pyrender will not be able to be imported (works fine in local terminal, but fails when doing this via ssh)

Could you fix this? it seems a bit urgent.
For now, i'll add a simple try except to the two lines you added

[NekoAsakura]

Oops, apologies for any trouble may caused.
I saw #324. This is because tkinter should not be initialised on a headless server unless an X window is configured with a virtual screen.
try-except block should be enough for this, as they are not expected to use a viewer on a headless server.

[Edit]

Here's a ref of how to setup X windows: https://stackoverflow.com/questions/40195740/how-to-run-openai-gym-render-over-a-server/48237220#48237220

Also need:

sudo apt install python3-tk

[zhouxian]

Ok thanks!