Cleanup and unify keyboard input.

[bruvzg]

• Unify keycode values (secondary label printed on a key), remove unused hard-coded Latin-1 codes.
• Unify IME behavior, add inline composition string display on Windows and X11.
• Add key_label (primary label printed on a key) value to the key events, and allow mapping actions to the key_label events.
• Add support for physical keyboard (Bluetooth, USB or Sidecar) handling on iOS.
• Remove LineEdit/TextEdit selected text when IME input begin.
• Add support for media key handling on macOS.

• Physical keyboard should always have keycode, key_label and physical_keycode set, and unicode set on key press only when it's relevant.
• IME only sends unicode key down evens, all other keys are ignored while it's active.
• Virtual keyboards send everything physical do, except physical_keycode.

Supported input modes:

	Android	iOS	Linux/X11	macOS	Windows	Web
Physical Keyboard	Yes 1	Yes 2	Yes	Yes	Yes	Yes 3
Virtual Keyboard	Yes	Yes	No 4	No 4	No 4	No
IME	5	5	Yes (inline)	Yes (inline)	Yes (inline)	No

Fixes #69830
Fixes #54797
Supersede #53682

Footnotes

1. Tested with Bluetooth and USB-OTG keyboards. ↩

2. Tested with Bluetooth and USB-OTG keyboards, Smart Connector case keyboard and Sidecar. ↩

3. key_label values aren't supported (generated from unicode and keycode as fallback). ↩

4. OS on-screen keyboards emulate physical keyboard. ↩ ↩² ↩³

5. Using custom virtual keyboard layout. ↩ ↩²

[Zireael07]

Can that picture go into official Godot docs?

[bruvzg]

Can that picture go into official Godot docs?

In some form, I definitely plan to add it (#69751).

[bruvzg]

This might also be needed for NixOS which puts its includes in non-standard directories:

Added. I guess I should do #71263 for the X11 libs to avoid this kind of issues.

[akien-mga]

Tested on Linux with en_US, fr_FR and da_DK keyboard layouts, seems to work great! Some tests with event.as_text_key_label():

French AZERTY, pressing all keys from top to bottom (remapping, on a physical US QWERTY):

²
Ampersand
É
QuoteDbl
Apostrophe
ParenLeft
Minus
È
UnderScore
Ç
À
ParenRight
Equal
A
Z
E
R
T
Y
U
I
O
P
BraceLeft
Dollar
Asterisk
Q
S
D
F
G
H
J
K
L
M
Ù
W
X
C
V
B
N
Comma
Semicolon
Colon
Exclam

The same on Danish keyboard layout:

½
1
2
3
4
5
6
7
8
9
0
Plus
Equal
Q
W
E
R
T
Y
U
I
O
P
Å
BraceRight
Apostrophe
A
S
D
F
G
H
J
K
L
Æ
Ø
Z
X
C
V
B
N
M
Comma
Period
Minus

I noticed a difference in the way modifiers are handled, but this may be intentional. Testing on French AZERTY, where:

• Physical key "2" has key label "É", and "2" is the "shifted" key.
• Physical key "E" has key label "E", and "€" is accessible via Alt Gr + E (on Linux with the default fr mapping).

Pressing Shift+É to get "2" prints:

Shift
Shift+É

Pressing Alt Gr+E to get "€" prints:

Alt
€

"€" is actually a key label on that layout: https://en.wikipedia.org/wiki/AZERTY

But the same also happens with extended mappings from the Linux keyboard layout which are not printed on the keys, e.g. Alt Gr+W gives "«" and Alt Gr+X gives "»". Those key combinations print:

Alt
«
Alt
»

It's probably different on Windows as these extended mappings are a Linux feature, so this can well be considered working as intended.

[akien-mga]

Thanks!

[vmedea]

I'm sorry but I think the change in of SUPER_* and HYPER_* constants is a bit weird here.

From a X11/Wayland perspective the old situation makes more sense? Like, at least the left and right SUPER ("windows") key are really separate keys. I'm not sure about HYPER.

Also there's a stale SUPER_R/SUPER_L in core/keyboard.h, if you really intend to remove them.

[bruvzg]

I'm sorry but I think the change in of SUPER_* and HYPER_* constants is a bit weird here.

None of the other platforms distinguish L/R Super, all use META, and no other key have Left/Right variant. It is possible to get L/R variants on other platforms, but if it's done it should be done for all keys (Ctrl, Alt, etc.) not just for Super/Meta and essentially nonexistent Hyper. There was PR to do it, but it was rejected.

Also there's a stale SUPER_R/SUPER_L in core/keyboard.h, if you really intend to remove them.

Indeed, missed them, should be removed.

[vmedea]

Ok, thanks, it wasn't clear to me that META was the same thing. I thought the key was entirely removed. Makes more sense then.

[Vivalzar]

I noticed a difference in the way modifiers are handled, but this may be intentional. Testing on French AZERTY, where:

• Physical key "2" has key label "É", and "2" is the "shifted" key.

Yes, this is intentional. All numbers on French keyboards are accessed using shift.

[h0lley]

InputEventKey does not necessarily have the key_label set, such as when it has been retrieved from InputMap.action_get_events(). In that case, how do we obtain the localized key label of an unicode char that has no keycode representation (if it had, we could use DisplayServer.keyboard_get_keycode_from_physical()). Example: umlauts.

apologies if that is not within the scope of this PR. didn't find any other place related to key_label.