BGFX shutdown does not reset properly

[PowerOfNames]

(Have read and confirm :) )

Describe the bug
A clear and concise description of what the bug is.

When calling bgfx::shutdown() but keeping the application alive, it currently seesm to not be possible to create a fresh bgfx context via bgfx::Init again from another thread. (Have an application where a dedicatd thread manages bgfx, and I want to be able to completely close the thread -> shutting bgfx down, and later to create a new thread with a fresh bgfx instance)

The first thing that creates an error is the s_renderFrameCalled field. This is not being reset to false during shutdown.

To Reproduce
Steps to reproduce the behavior:

1. Create a thread
2. Initialize bgfx on it
3. Shut bgfx down
4. join the thread and delete it
5. create a new thread
6. initialize bgfx there -> error occurs (wrong thread context)

Expected behavior
A clear and concise description of what you expected to happen.

If bgfx has been shutted down, it should reset to its original state completely, so its possible to keep the application alive and create bgfx on another thread freshly.

Screenshots
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Additional context
Add any other context about the problem here. OS, drivers, etc.

Should not be necessary, but its Win11, using Vulkan backend.

The fix is simple but I'm not sure if anything else was overlocked.
Besides that: Great framework, its simple and fun to use and expand :)

[mcourteaux]

Related: #3381 #3320 #2154 #1998

[bkaradzic]

Related: #1549

[bkaradzic]

So I understand correctly, you're trying to move bgfx::renderFrame of the thread where it was originally called?

Or you're using bgfx in single threaded mode?

[PowerOfNames]

Yes exactly.
I do an Init, do some rendering stuff and then call bgfx::shutdown after its done and get rid of the thread that owned the rendering.
Later during the same runtime of the application, I create a new thread and want to repeat the process -> Init, bgfx::renderFrame -> rendering -> later shutdown.

I am also using the default allocator rn and it seems to also break down in this process (during second init) but I could not confirm that that is not a me-issue, so I wasn't mentioning it.

[bkaradzic]

So most of platforms want to have that bgfx::renderFrame on thread that's created by OS. And you're unable to freely move it around. It might work fine on some platforms, but it's not flexible everywhere.