Regression 11.5: key events not triggered when an IME language is active (windows)

[expikr]

If you have a CJK language active then the corresponding keypressed/keyreleased events are not triggered.

It's the same kind of problem that Minecraft has (which uses glfw), so it might have something to do with naive handling of scancode/virtual-key codes.

tested on 11.5

EDIT: works correctly in 11.4 so it's a regression.

test code:

local vkeycode_count = 0
local scancode_count = 0

function love.keypressed(vkey,scan,isRepeat)
    if vkey=="w" then vkeycode_count = vkeycode_count + 1 end
    if scan=="w" then scancode_count = scancode_count + 1 end
end
function love.keyreleased(vkey,scan)
    if vkey=="w" then vkeycode_count = vkeycode_count - 1 end
    if scan=="w" then scancode_count = scancode_count - 1 end
end
function love.draw()
    love.graphics.print(
        "love.keyboard.isDown('w') = "         .. (love.keyboard.isDown('w')         and "true" or "false") .. "\n" .. 
        "love.keyboard.isScancodeDown('w') = " .. (love.keyboard.isScancodeDown('w') and "true" or "false") .. "\n" .. 
        "vkey w press count = " .. vkeycode_count .. "\n" ..
        "scan w press count = " .. scancode_count
    )
end

[slime73]

Is there a game you know of that does work as you expect on your system?

That being said, since love uses SDL for input handling, if it is even possible for apps to control that behaviour then SDL's code would have to change rather than love's code.

[expikr]

re-tested 11.4 works correctly, so it's a regression.

Is there a game you know of that does work as you expect on your system?

Overwatch for example, and basically pretty much any game that started off with an AAA-ish engine.

[slime73]

Are you able to test directly with the latest SDL and file a bug there if needed? love 11.4 used SDL 2.0.18, and 11.5 uses 2.28.5.

[expikr]

latest SDL.dll fails for both 11.4 and 11.5

11.4's SDL.dll works when copied to 11.5 as well.

So it's upstream.

[slime73]

A couple clarifying questions:

• do you get love.textedited and love.textinput events in that situation?
• is an IME dialog / UI element visible at all?
• if you turn text input off, does the behaviour change?

[expikr]

1. first time I've heard of those events. Will test.
2. no element visible whatsoever. Just like with Minecraft
3. what do you mean by turning it off?

[slime73]

first time I've heard of those events.

If you ever want to have a text box or handle typed text from users, you'll definitely want to use those instead of love.keypressed (whereas the latter is good for other game input unrelated to text). :)

what do you mean by turning it off?

love.keyboard.setTextInput

[expikr]

In both versions, during IME mode no textinput events are generated, and textedited events are only generated when changing the key pressed (repeat presses do not generate new events, nor do key releases).

With love.keyboard.setTextInput(false) the IME toolbar is locked into alphanumeric mode, and the keypresses registers correctly.

So the only difference between 11.4 and 11.5 is whether or not isDown/isScancodeDown/keypressed/keyreleased registers during IME, the textinput/textedit/setTextInput behaviors are identical.

local vkeycode_accu = 0
local scancode_accu = 0
local input_count = 0
local edit_count = 0


function love.mousepressed(x,y,button,istouch,presses)
    if button==3 then love.keyboard.setTextInput( not love.keyboard.hasTextInput() ) end
end

function love.textinput(text)
    input_count = input_count + 1
end

function love.textedited( text, start, length )
    edit_count = edit_count + 1
end

function love.keypressed(vkey,scan,isRepeat)
    if vkey=="w" then vkeycode_accu = vkeycode_accu + 1 end
    if scan=="w" then scancode_accu = scancode_accu + 1 end
end
function love.keyreleased(vkey,scan)
    if vkey=="w" then vkeycode_accu = vkeycode_accu - 1 end
    if scan=="w" then scancode_accu = scancode_accu - 1 end
end
function love.draw()
    love.graphics.print(
        "love.keyboard.isDown('w') = "         .. (love.keyboard.isDown('w')         and "true" or "false") .. "\n" .. 
        "love.keyboard.isScancodeDown('w') = " .. (love.keyboard.isScancodeDown('w') and "true" or "false") .. "\n" .. 
        "vkey w accu = " .. vkeycode_accu .. "\n" ..
        "scan w accu = " .. scancode_accu .. "\n" ..
        "textinput count = " .. input_count .. "\n" .. 
        "textedited count = " .. edit_count
    )
end

[ericoporto]

@expikr can you verify if SDL release 2.24.2 already had this issue or if it still worked? The dll can be found in either the win32 assets (x86 or x64).

[expikr]

2.24.2 fails.

[slime73]

no element visible whatsoever

With love.keyboard.setTextInput(false) the IME toolbar is locked into alphanumeric mode

I'm a bit confused by this - is there IME-related UI visible and active while text input is active, or is there not?

[expikr]

The IME toolbar is a status indicator in the systray, next to the system clock.

The IME character selection overlay element is never visible in Love2D.

[expikr]

is this also fixed by switching to sdl3?

[slime73]

Yes, because text input is opt-in on all platforms now. But Sam still has the SDL issue open so I assume he has more plans for investigating or changing what happens to key presses while text input and an IME are active.