Fix documentation on how to get the keycode string from a physical_keycode

[jitspoe]

• Fixes Documentation on physical_keycode is incorrect #82091

Bugsquad edit: Linked issue.

[akien-mga]

Added @YuriSizov's suggestion, and further reworked it to be valid code, with a C# example. It's now a full _input function example as C# needs @event to be properly defined in that context.

I tested both GDScript and C# snippets successfully.

[akien-mga]

Thanks!

[stephanbogner]

Are we sure the code is working correctly?
(If not I'd open an issue for get_keycode_string)

I am on German QWERTZ keyboard on a Mac where the following happens:

• Press Z → Z ✅
• Press Q → Q ✅
• Press + → Plus ✅ (even though I'd prefer +)
• Press - → Minus ✅ (even though I'd prefer -)
• Press Ü → BracketLeft ❌
• Press Ä → Apostrophe ❌
• Press Ö → Semicolon ❌

It's really weird, because it seems the Umlauts (ÄÖÜ) fall back to an US keyboard layout but everything else works as expected.

Also it doesn't put it out in the user's language but that's probably a different issue/topic (which would be important when showing it to the actual user).

[AThousandShips]

If you're using physical_keycode that's how it works, see the documentaiton:

Represents the physical location of a key on the 101/102-key US QWERTY keyboard, which corresponds to one of the Key constants.

The instruction is for how to convert that physical keycode into a human readable string of that keycode, not of the layout specific keycode, for that use keycode

However if it does return Z for the Y key on the QWERTY keyboard that is a bug or an OS side issue, that should be investigated, but the umlauts (assuming they are the keys near the enter key, next to P) are correct

It does however seem like you're using keycode not physical_keycode as you are getting Z mapped to Z, the event should have keycode=Z, physical_keycode=Y a QWERTZ layout, and use the bracket keys for the umlauts AFAIK as they don't have keycodes (you need to use the unicode instead for those)

[stephanbogner]

@AThousandShips

Ah ok, I understood it as physical refers to the physical keyboard I have in front of me (my bad) ... but there still seems to be a bug somewhere (gosh, how much I hate cross-platform issues).

I used the code from the docs:

func _input(event):
	if event is InputEventKey:
		var keycode = DisplayServer.keyboard_get_keycode_from_physical(event.physical_keycode)
		print(OS.get_keycode_string(keycode))

It seems to mix layouts in a weird manner:
As you can see from the video when typing the keyboard works as normal (not a different layout applied), but the output from the log is like a mix of the US and the German QWERTY layout, e.g.:

Ü = BracketLeft (US)
# = NumberSign (German)
- = Minus (German)
ß = Minus (US)
´ = Equal (US)

Tested on a MacBook Pro with 14.6.1 (Sonoma) and Godot v4.2.2

IMG_0383.mp4

[AThousandShips]

Please open an issue to investigate this, could be many different issues, also please provide a clear log of the results (I'd suggest making sure it prints both the keycode and the physical keycode, both in human readable forms, to evaluate), and an MRP

[stephanbogner]

@AThousandShips

Will do!

Would the following be a good setup to test it in your opinion:

func _input(event):
	if event is InputEventKey and event.is_released():
		print("")
		print("Keycode: ", event.keycode, " -> ", OS.get_keycode_string(event.keycode))
		print("Physical keycode: ", event.physical_keycode, " -> ", OS.get_keycode_string(event.physical_keycode))
		var keycode_from_physical = DisplayServer.keyboard_get_keycode_from_physical(event.physical_keycode)
		print("Keycode (from physical): ", keycode_from_physical, " -> ", OS.get_keycode_string(keycode_from_physical))

Which might already have the conclusion:
✅ Pressing - prints:

Keycode: 45 -> Minus
Physical keycode: 47 -> Slash
Keycode (from physical): 45 -> Minus

❌ Pressing ß prints:

Keycode: 45 -> Minus
Physical keycode: 45 -> Minus
Keycode (from physical): 45 -> Minus

❌ Pressing Ä prints:

Keycode: 39 -> Apostrophe
Physical keycode: 39 -> Apostrophe
Keycode (from physical): 39 -> Apostrophe

[AThousandShips]

That doesn't look incorrect, remember that there aren't keycodes for symbols not on the US keyboard, they are mapped to the one most relevant, so ß should be correct, as it is where - is in the US keyboard, same for Ä, which is where ' is on a US keyboard

Compare with the correct layout here

[bruvzg]

Pressing ß prints:

Both keycode and physical_keycode are limited to the set of codes on the 101/102-key US QWERTY keyboard, and there's no ß on it. If you want what's to get what's printed on the key, use key_label instead.

[AThousandShips]

Forgot about key_label

For more info see here

[stephanbogner]

Ahhhh! Thanks @bruvzg ❤️ That does the trick! I didn't expect you have to plug something else into OS.get_keycode_string

I will post an example here for the people that also get confused:

Press Ä on a QWERTZ keyboard will result in:

• event.key_label = 196
• OS.get_keycode_string(event.key_label) = Ä
• OS.get_keycode_string(event.keycode) = Apostrophe
• OS.get_keycode_string(event.physical_keycode) = Apostrophe

[bruvzg]

• physical_keycode → position of the key, e.g., WASD for movement.
• keycode → basic Latin shortcut available on most layouts (but might be in different places), e.g., Ctrl+C/Ctrl+V for copy/paste.
• key_label → what's printed on the key.
• unicode → text input (with modifiers, and not necessarily associated with a real key press, since can be emitted by IME/virtual keyboard, etc.).

More examples (I should add this image and some info to the docs):

[Zireael07]

More examples (I should add this image and some info to the docs):

Yes PLEASE!