win32: Add keycode_to_key method for getting logical keys from physical

[Aceeri]

#2678

Looking for thoughts on this, maybe it makes more sense to have a KeyboardLayout struct that you can query, but the main usecase I (and other game devs) have for this is giving correct mappings in games.

• Tested on all platforms changed
• Added an entry to the changelog module if knowledge of this change could be valuable to users
• Updated documentation to reflect any user-facing changes, including notes of platform-specific behavior
• Created or updated an example program if it would help users understand this functionality

[kchibisov]

The problem is that on platforms like linux we'd need to have a running event loop. I'm also not sure if the function is MT safe, so implementing via global state like that won't generally work, and the function should be a method on a theoretical Keymap struct.

[Aceeri]

The problem is that on platforms like linux we'd need to have a running event loop. I'm also not sure if the function is MT safe, so implementing via global state like that won't generally work, and the function should be a method on a theoretical Keymap struct.

Gotcha, makes sense. Is the LayoutCache still usable if we were able to move this into the event loop + copy mappings over to a separate Keymap struct (stored on the Window?)? I'm not super familiar with how the main thread safeness works here tbh.

Also do you know if that applies to the appkit/macos version too (#4455)? Just trying to figure out which parts to try to salvage if I try to get this into the event loop.

[kchibisov]

Can not speak for windows here, for linux caching is useless.

[Aceeri]

Can not speak for windows here, for linux caching is useless.

As in you can't cache across frames at all? I'll take a bit of a look into the linux code, I haven't really touched it before so I'm pretty blind.

[kchibisov]

In a sense that there's no point to cache anything, you have access to the entire keymap and thus you get things from it. It could have cache internally...

[NeuralModder]

Looking for thoughts on this, maybe it makes more sense to have a KeyboardLayout struct that you can query, but the main usecase I (and other game devs) have for this is giving correct mappings in games.

Interesting that you would say this. I'm also looking to use this in a game, but according to my co-contributors the displayed key labels changing when the keyboard layout changes would be "disorienting", so we want to store the keyboard layout information (inside of RON) instead of just querying the currently active layout. So a KeyboardLayout struct seems like it'd make more sense for that, though we'd still probably have to distill it into something serializable and with only the information we need.