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The key you just pressed is not recognized by SDL
Jethro Beekman
Guest
Post Posted: Sat Nov 09, 2013 2:21 am
Quote:
Anyway, as long as we get an event for every keypress it's a huge
improvement.

Completely agreed.

Quote:
My little test program

This is on US International with dead keys:

SDL_KEYDOWN: Keycode: Right Shift Scancode: Right Shift
SDL_KEYDOWN: Keycode: 6 Scancode: 6
SDL_KEYUP: Keycode: 6 Scancode: 6
SDL_KEYUP: Keycode: Right Shift Scancode: Right Shift
SDL_KEYDOWN: Keycode: A Scancode: A
SDL_KEYUP: Keycode: A Scancode: A
SDL_EventState(SDL_TEXTINPUT, SDL_ENABLE)
SDL_KEYDOWN: Keycode: Right Shift Scancode: Right Shift
SDL_KEYDOWN: Keycode: 6 Scancode: 6
SDL_KEYUP: Keycode: 6 Scancode: 6
SDL_KEYUP: Keycode: Right Shift Scancode: Right Shift
SDL_KEYDOWN: Keycode: A Scancode: A
SDL_TEXTINPUT: â
SDL_KEYUP: Keycode: A Scancode: A

I think this is the way it should be. All dead keys on my keyboard generate the
correct Keycode/Scancode AFAICT.

I still get "The key you just pressed is not recognized by SDL." but I applied
your patch to 2.0.0 - I assume this is a non-issue.

Quote:
I'd be glad about feedback regarding the patch.

Looks good to me. Maintainers: please merge.

Jethro

On 24-08-13 18:15, Daniel Gibson wrote:> Hi,
Quote:

I think I have fixed the X11 backend now to produce SDL_KEYDOWN/UP
events for dead keys as well, just like SDL2 does on Windows.

My little test program[1] yields the following output on my machine
(german layout with sundeadkeys), when pressing ^ and a, then clicking
into the window and pressing ^ and a again:
* Unpatched SDL2 release version:
The key you just pressed is not recognized by SDL. To help get this
fixed, please report this to the SDL mailing list <sdl at libsdl.org> X11
KeyCode 0 (-Cool, X11 KeySym 0x0 ((null)).
SDL_TEXTINPUT: â
SDL_EventState(SDL_TEXTINPUT, SDL_DISABLE)
The key you just pressed is not recognized by SDL. To help get this
fixed, please report this to the SDL mailing list <sdl at libsdl.org> X11
KeyCode 0 (-Cool, X11 KeySym 0x0 ((null)).
^CReceived SDL_QUIT - bye!

* SDL2 latest hg with my patch[2]:
SDL_KEYDOWN: Keycode: ` Scancode: `
SDL_KEYUP: Keycode: ` Scancode: `
SDL_KEYDOWN: Keycode: A Scancode: A
SDL_TEXTINPUT: â
SDL_KEYUP: Keycode: A Scancode: A
SDL_EventState(SDL_TEXTINPUT, SDL_DISABLE)
SDL_KEYDOWN: Keycode: ` Scancode: `
SDL_KEYUP: Keycode: ` Scancode: `
SDL_KEYDOWN: Keycode: A Scancode: A
SDL_KEYUP: Keycode: A Scancode: A
^CReceived SDL_QUIT - bye!

OK, it's still strange that the Keycode is ` there instead of ^ (some
fuckup in X11KeyCodeToUcs4()?). With the same keyboard layout but
without dead keys (de nodeadkeys instead of de sundeadkeys) I get
Keycode ^ Scancode `...
Anyway, as long as we get an event for every keypress it's a huge
improvement.
Otherwise this is equivalent to the output Boolsheet from IRC got on
Windows with a swiss german layout:
SDL_KEYDOWN: Keycode: ^ Scancode: =
SDL_KEYUP: Keycode: ^ Scancode: =
SDL_KEYDOWN: Keycode: A Scancode: A
SDL_TEXTINPUT: â
SDL_KEYUP: Keycode: A Scancode: A
SDL_EventState(SDL_TEXTINPUT, SDL_DISABLE)
SDL_KEYDOWN: Keycode: ^ Scancode: =
SDL_KEYUP: Keycode: ^ Scancode: =
SDL_KEYDOWN: Keycode: A Scancode: A
SDL_KEYUP: Keycode: A Scancode: A
Received SDL_QUIT - bye!

So the problem was, that dead keys are filtered out with XFilterEvent()
(in X11_DispatchEvent in SDL_x11events.c). Furthermore XFilterEvent()
modifies the event (sets keycode to 0 for the key combined with the dead
key).
My fix[2] is to save the keycode and the type (KeyPress/KeyRelease)
before calling XFilterEvent() for KeyPress/KeyRelease() events and to
call SDL_SendKeyboardKey() accordingly if XFilterEvent() returned True.

I'd be glad about feedback regarding the patch.

Cheers,
Daniel

[1] Test program: http://pastebin.com/sqxtTNzS
[2] The patch: http://pastebin.com/6VWH3m6s

Am 19.08.2013 00:49, schrieb Sik the hedgehog:
Quote:
Personally, I'd consider any key not producing SDL_KEYUP/DOWN to be a
bug, since they're supposed to represent the key and not the
character. The only two exceptions I can think are Pause (keyboard
sends release as soon as it sends press) and stuff like macro keys
(intercepted by the keyboard and never sent to the computer).

2013/8/18, Daniel Gibson <metalcaedes at gmail.com>:
Quote:
I have thought a bit more about it and IMHO it would be nice if dead
keys at least produced SDL_KEYUP/DOWN events when SDL_TEXTINPUT is
disabled.

Attached are a patch which implements that for X11 and a small
test-program that prints current SDL_KEYUP/DOWN and SDL_TEXTINPUT events
and toggles SDL_TEXTINPUT when clicking into the window.

What's the behavior for dead keys on other platforms (Windows, OSX, ..)
(with SDL_TEXTINPUT enabled/disabled?)?
Do they produce SDL_KEY* events or not?

BTW, I find it strange that SDL_TEXTINPUT is enabled by default on some
platforms (those without a screen keyboard?) and not on others, that
feels inconsistent (code in SDL_VideoInit()). There's even a comment
which questions this behavior: "Actually, come to think of it, you
needed to call SDL_EnableUNICODE(1) in SDL 1.2 before you got text input
events." ...

Cheers,
Daniel

Am 17.08.2013 03:47, schrieb Daniel Gibson:
Quote:
Hi,

I found out some things.. basically XFilterEvent() returns True if the
event is the first keypress of a dead key, thus X11_DispatchEvent()
returns (about line 276 and following).

When calling XFilterEvent() on new events:
The first KeyPress event then contains:
- X11 KeyCode 49 (which seems to belong to my ^ key, => ok).
- X11 KeySym 0xFE52 (dead_circumflex)
The second KeyPress event (after ^ pressing again) contains:
- X11 KeyCode 0
- X11 KeySym 0
- Text "^"
- the keysym returned from Xutf8LookupString() is 0x5E (asciicircum)
- the keysym is also asciicircum when typing ^ a for ā btw
- and here you also get this "The key you just pressed is not
recognized..." message

The KeyRelease event is "X11 KeyCode 49, X11 KeySym 0xFE52
(dead_circumflex)" both times.

When *not* calling XFilterEvent() on new KeyPress/Release events and
pressing ^ twice:
Both KeyPress and KeyRelease events contain:
- X11 KeyCode 49
- X11 KeySym 0xFE52 (dead_circumflex).
Both KeyPress events contain:
- Text: "^"
- the keysym returned from Xutf8LookupString() is 0x5E
(dead_circumflex)


So it first looks like not calling XFilterEvent() on KeyPress/Release
events could do the trick.. however that would certainly screw up dead
keys in textinput (e.g. ^+a for ā) and I don't know what other
implications it may have.

I'm not very familiar with the SDL2 textediting stuff, in the
documentation it kinda looks like one should call SDL_StartTextInput()
before expecting SDL_TEXTINPUT events, but it looks like those events
are fired all the time (when a keypress event has a non-empty text from
Xutf8LookupString).
If one is really expected to call SDL_StartTextInput() then that (and
SDL_StopTextInput()) could be used to disable/re-enable calling
XFilterEvent().
If SDL_TEXTINPUT events should be coming in without calling
SDL_StartTextInput() first this probably is no option.

Maybe there are other clever tricks, maybe with XPeekEvent() or
something?

Cheers,
Daniel


Am 17.08.2013 02:53, schrieb Sam Lantinga:
Quote:
It looks like the X server eats the first keypress for composition and
then outputs a 0 keysym for the second press. We can never do anything
useful with that, so I disabled the message. If you find out more
information and/or a smarter way to deal with that, then by all means,
let me know! :)



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The key you just pressed is not recognized by SDL
Sam Lantinga


Joined: 10 Sep 2009
Posts: 1765
Post Posted: Sun Nov 10, 2013 10:49 pm
This looks good.  I wrote a patch using this approach here:https://hg.libsdl.org/SDL/rev/713c6a333c33



Thanks!



On Sat, Aug 24, 2013 at 6:15 PM, Daniel Gibson wrote:
Quote:
Hi,

I think I have fixed the X11 backend now to produce SDL_KEYDOWN/UP events for dead keys as well, just like SDL2 does on Windows.

My little test program[1] yields the following output on my machine (german layout with sundeadkeys), when pressing ^ and a, then clicking into the window and pressing ^ and a again:
* Unpatched SDL2 release version:
The key you just pressed is not recognized by SDL. To help get this fixed, please report this to the SDL mailing list X11 KeyCode 0 (-Cool, X11 KeySym 0x0 ((null)).
SDL_TEXTINPUT: â
SDL_EventState(SDL_TEXTINPUT, SDL_DISABLE)
The key you just pressed is not recognized by SDL. To help get this fixed, please report this to the SDL mailing list X11 KeyCode 0 (-Cool, X11 KeySym 0x0 ((null)).
^CReceived SDL_QUIT - bye!

* SDL2 latest hg with my patch[2]:
SDL_KEYDOWN: Keycode: ` Scancode: `
SDL_KEYUP: Keycode: ` Scancode: `
SDL_KEYDOWN: Keycode: A Scancode: A
SDL_TEXTINPUT: â
SDL_KEYUP: Keycode: A Scancode: A
SDL_EventState(SDL_TEXTINPUT, SDL_DISABLE)
SDL_KEYDOWN: Keycode: ` Scancode: `
SDL_KEYUP: Keycode: ` Scancode: `
SDL_KEYDOWN: Keycode: A Scancode: A
SDL_KEYUP: Keycode: A Scancode: A
^CReceived SDL_QUIT - bye!

OK, it's still strange that the Keycode is ` there instead of ^ (some fuckup in X11KeyCodeToUcs4()?). With the same keyboard layout but without dead keys (de nodeadkeys instead of de sundeadkeys) I get Keycode ^ Scancode `...
Anyway, as long as we get an event for every keypress it's a huge improvement.
Otherwise this is equivalent to the output Boolsheet from IRC got on Windows with a swiss german layout:
SDL_KEYDOWN: Keycode: ^ Scancode: =
SDL_KEYUP: Keycode: ^ Scancode: =
SDL_KEYDOWN: Keycode: A Scancode: A
SDL_TEXTINPUT: â
SDL_KEYUP: Keycode: A Scancode: A
SDL_EventState(SDL_TEXTINPUT, SDL_DISABLE)
SDL_KEYDOWN: Keycode: ^ Scancode: =
SDL_KEYUP: Keycode: ^ Scancode: =
SDL_KEYDOWN: Keycode: A Scancode: A
SDL_KEYUP: Keycode: A Scancode: A
Received SDL_QUIT - bye!

So the problem was, that dead keys are filtered out with XFilterEvent() (in X11_DispatchEvent in SDL_x11events.c). Furthermore XFilterEvent() modifies the event (sets keycode to 0 for the key combined with the dead key).
My fix[2] is to save the keycode and the type (KeyPress/KeyRelease) before calling XFilterEvent() for KeyPress/KeyRelease() events and to call SDL_SendKeyboardKey() accordingly if XFilterEvent() returned True.

I'd be glad about feedback regarding the patch.

Cheers,
Daniel

[1] Test program: http://pastebin.com/sqxtTNzS
[2] The patch: http://pastebin.com/6VWH3m6s

Am 19.08.2013 00:49, schrieb Sik the hedgehog:

Quote:
Personally, I'd consider any key not producing SDL_KEYUP/DOWN to be a
bug, since they're supposed to represent the key and not the
character. The only two exceptions I can think are Pause (keyboard
sends release as soon as it sends press) and stuff like macro keys
(intercepted by the keyboard and never sent to the computer).

2013/8/18, Daniel Gibson:
Quote:
I have thought a bit more about it and IMHO it would be nice if dead
keys at least produced SDL_KEYUP/DOWN events when SDL_TEXTINPUT is
disabled.

Attached are a patch which implements that for X11 and a small
test-program that prints current SDL_KEYUP/DOWN and SDL_TEXTINPUT events
and toggles SDL_TEXTINPUT when clicking into the window.

What's the behavior for dead keys on other platforms (Windows, OSX, ..)
(with SDL_TEXTINPUT enabled/disabled?)?
Do they produce SDL_KEY* events or not?

BTW, I find it strange that SDL_TEXTINPUT is enabled by default on some
platforms (those without a screen keyboard?) and not on others, that
feels inconsistent (code in SDL_VideoInit()). There's even a comment
which questions this behavior: "Actually, come to think of it, you
needed to call SDL_EnableUNICODE(1) in SDL 1.2 before you got text input
events." ...

Cheers,
Daniel

Am 17.08.2013 03:47, schrieb Daniel Gibson:
Quote:
Hi,

I found out some things.. basically XFilterEvent() returns True if the
event is the first keypress of a dead key, thus X11_DispatchEvent()
returns (about line 276 and following).

When calling XFilterEvent() on new events:
   The first KeyPress event then contains:
   - X11 KeyCode 49 (which seems to belong to my ^ key, => ok).
   - X11 KeySym 0xFE52 (dead_circumflex)
   The second KeyPress event (after ^ pressing again) contains:
   - X11 KeyCode 0
   - X11 KeySym 0
   - Text "^"
     - the keysym returned from Xutf8LookupString() is 0x5E (asciicircum)
       - the keysym is also asciicircum when typing ^ a for ā btw
   - and here you also get this "The key you just pressed is not
     recognized..." message

The KeyRelease event is "X11 KeyCode 49, X11 KeySym 0xFE52
(dead_circumflex)" both times.

When *not* calling XFilterEvent() on new KeyPress/Release events and
pressing ^ twice:
   Both KeyPress and KeyRelease events contain:
   - X11 KeyCode 49
   - X11 KeySym 0xFE52 (dead_circumflex).
   Both KeyPress events contain:
   - Text: "^"
     - the keysym returned from Xutf8LookupString() is 0x5E
       (dead_circumflex)


So it first looks like not calling XFilterEvent() on KeyPress/Release
events could do the trick.. however that would certainly screw up dead
keys in textinput (e.g. ^+a for ā) and I don't know what other
implications it may have.

I'm not very familiar with the SDL2 textediting stuff, in the
documentation it kinda looks like one should call SDL_StartTextInput()
before expecting SDL_TEXTINPUT events, but it looks like those events
are fired all the time (when a keypress event has a non-empty text from
Xutf8LookupString).
If one is really expected to call SDL_StartTextInput() then that (and
SDL_StopTextInput()) could be used to disable/re-enable calling
XFilterEvent().
If SDL_TEXTINPUT events should be coming in without calling
SDL_StartTextInput() first this probably is no option.

Maybe there are other clever tricks, maybe with XPeekEvent() or
something?

Cheers,
Daniel


Am 17.08.2013 02:53, schrieb Sam Lantinga:
Quote:
It looks like the X server eats the first keypress for composition and
then outputs a 0 keysym for the second press.  We can never do anything
useful with that, so I disabled the message.  If you find out more
information and/or a smarter way to deal with that, then by all means,
let me know! :)



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SDL mailing list

http://lists.libsdl.org/listinfo.cgi/sdl-libsdl.org

_______________________________________________
SDL mailing list

http://lists.libsdl.org/listinfo.cgi/sdl-libsdl.org