Add Control+Shift+U (rebindable) action for Unicode input, show hex as it is entered.

[bruvzg]

Implements and closes godotengine/godot-proposals#10654

• Adds ui_unicode_start action (set to Control+Shift+U by default) start Unicode hex input (code submitted/canceled by ui_text_submit/ui_cancel actions).
• Adds hex code display (for both Alt+ and new action).

Screen.Recording.2024-09-05.at.18.18.48.mov

[Calinou]

Tested locally on Fedora 40 KDE X11, there are some issues when you use Shift + home row keys to enter numbers on a French AZERTY (fr-oss) keyboard layout. It remains stuck after you press other keys such as arrow keys:

unicode_input.mp4

Using screenkey to show pressed keys.

This does not occur when using the numpad to enter numbers, as seen at the end of the video above.

[bruvzg]

It remains stuck after you press other keys such as arrow keys:

Is it supposed to do something until you press Enter/Esc to commit/cancel it? (Video seems to only show static frame with Ctrl+R visible, not sure if it's an issue with recording or Firefox, and downloaded video refuse to open at all).

[akien-mga]

It remains stuck after you press other keys such as arrow keys:

Is it supposed to do something until you press Enter/Esc to commit/cancel it? (Video seems to only show static frame with Ctrl+R visible, not sure if it's an issue with recording or Firefox, and downloaded video refuse to open at all).

For the record, I tested the same feature in Firefox, and it seems to accept the following keys to end the edit mode and process the character:

• Enter/Return
• Space
• Ctrl
• Shift

Ctrl and Shift are maybe a bit far fetched, but in our implementation I'd feel natural for Space to work too. Or we could support the same keys as Firefox for convenience. That being said I see merit in using ui_text_submit over ui_accept, so maybe it's fine as is.

[akien-mga]

Tested locally on Fedora 40 KDE X11, there are some issues when you use Shift + home row keys to enter numbers on a French AZERTY (fr-oss) keyboard layout. It remains stuck after you press other keys such as arrow keys:

I confirm that with a French keyboard the main number keys can't be used.

After pressing Ctrl+Shift+U:

• Pressing é à & " (first-level keys on the 2 0 1 3 key positions) inputs only 20
• Pressing Shift+é (2) Shift+à (0) Shift+& (1) Shift+" (3) also only inputs 20

[KoBeWi]

The behavior is weird when you move the caret:

GR9HB1XCsV.mp4

[bruvzg]

The behavior is weird when you move the caret

This is a side effect of #87479 (this change seems fine, but I have not accounted for this behavior, the same change probably should be done for LineEdit), should be fixed now.

Pressing é à & " (first-level keys on the 2 0 1 3 key positions) inputs only 20
Pressing Shift+é (2) Shift+à (0) Shift+& (1) Shift+" (3) also only inputs 20

Should work now, both with and w/o Shift (tested on macOS), I forgot there are keyboard layouts with non-primary level numbers.

That being said I see merit in using ui_text_submit over ui_accept, so maybe it's fine as is.

Changed it to use both ui_accept and ui_text_submit, not sure about Shift and Ctrl.

[bruvzg]

this change seems fine, but I have not accounted for this behavior, the same change probably should be done for LineEdit

Updated LineEdit to handle IME and this in the same way TextEdit do.

[akien-mga]

Needs rebase, and should be good to merge.

[akien-mga]

Thanks!