"cannot connect to X server" while trying to connect to PyBullet in WSL

Question

I am currently using a windows machine, and am busy with some Genetic Algorithm stuff that relies on using a PyBullet virtual environment to test out the locomotive capacity of my "robots". The project I'm working on required me to use multi-threading, so my lecturer recommended that I install WSL to do so because apparently it does not work on Windows.

I installed WSL, and created a python virtual environment to work in. Everything was perfectly fine until I tried to connect to a PyBullet server, which produced the following output:

pybullet build time: Nov 27 2022 13:20:33
startThreads creating 1 threads.
starting thread 0
started thread 0 
argc=2
argv[0] = --unused
argv[1] = --start_demo_name=Physics Server
ExampleBrowserThreadFunc started
X11 functions dynamically loaded using dlopen/dlsym OK!

        cannot connect to X server

What can I do to fix this? Please ask if more information on my setup is needed :)

Answer 1

It looks like your script wants to open some sort of graphical user interface.
You can try to install an X11 server on windows and configure this in WSL. That way you can open a graphical window in WSL. You should be able to find some tutorials online, but it can be a bit tedious. This could help you to get started, but there are multiple ways and tools.
Later versions of WSL should support graphical interfaces out-of-the-box. I think you'll need Windows 11. (However, I have never tried it so far)
This might help.

Answer 2

So I managed to fix the issue. I am not sure exactly why WSL was failing to launch the GUI application, I first thought it had something to do with X11, but I have the lastest version of WSL, which is supposed to have native GUI support. Next, I thought it had something to do with the python packages, because I had a working version of the code in a Virtual environment on my normal windows 11, I just didn't use it because it was unable to do multiprocessing. So to solve this, I copied the libs folder from the venv in my windows to the venv on my WSL. For some reason, it solved the problem. My initial reason for not doing this was because it didn't say I was missing any dependencies.

Thanks for those who tried to help though.