Unitl now the video menu showed all known renderer libs (gl1, gl3, vk
and soft), regardless if the lib was available or not. Rework the
renderer selection logic to skip over non existent renderer libs:
Generate an array combining the menu string and cvar string of all
available renderer libs, use this array instead of the hardcoded array.
While at it simplify the code a little bit.
So far I haven't seen a restart loop, but at least in theory they'e
possible. Because its hard to break out of such loop, especially on
Windows were interaction with the taskmanager is required, play save
and restart max. 3 times in a row.
The timeout specifies how long Vulkan waits for the next frame becoming
available. On the one hand we need to take the vsync or the possibility
that we get scheduled away for longer times into account. On the other
hand we don't want to wait for too long, the game may run into the
timeout after its windows was minimized, etc. 500 milliseconds sounds
like a good compromise.
Some GPU drivers set a maximal extent size of 0x0 when the window gets
minimized. One example is Intel on Windows. A swapchain with extent
size of 0x0 is invalid, so we cannot reinitialize the renderer... Work
around that by postponing the restart as long as the maxmimal extent
size stays 0x0.
This could should be done in the client (don't call into th renderer
when the window is minimized), but it would need a lot of changes
to the client <-> renderer interactions. So take the easy route.
The client might call into the renderer after it was shut down by
`VID_ShutdownRenderer()` or initialized `VID_LoadRenderer()`. This
is arguably a client bug, but hard to fix on client side and not
a problem for all other renderers. Work around it by marking the
current frame as 'not started' at Vulkan shutdown and init.
This is more in line with the rest of the code. Reinitializing the
internal state when building a new context is saver than relying on
Vulkan telling us that something is wrong an reacting to that.
Just calling `QVk_Shutdown()` is wrong. It doesn't wait for Vulkan to
finish, which can cause crashes. And it leaks some ressources which
makes the GPU driver unhappy.
The ref_vk renderer was written for vkQ2 which has differend renderer
<-> client semantics. In YQ2 we can end up initializing or shutting the
renderer down several times. Not by the client, but by the client not
knowing of the renderer has already initialized / shutdown it's internal
state. This is fatal, leading to ressource leaks, crashes and other fun.
Introduce a new global variable `vk_initialize` and use it to track if
we're initialized or not.
Since `vid_fullscreen` isn't special anymore, it's completely handled by
`Vid_Restart_f()`, which in turn simplifies the spaghetti code in the vk
renderer. If I understand that glibberish correctly the only we need to
handle is the partial restart in `QVk_Restart()`.
This function will be used to replace the vid_fullscreen->modified
mechanism used the communicate renderer configuration restarts to the
client with a proper proper API. The implementation is backward
compatible, existing renderers are still working.
