* Fixes for IME Composition Truncation + Addition of SDL_ClearComposition, SDL_IsTextInputShown
* Fixed: Documentation and code style issues raised during code review.
Based on a patch by Jochen Schäfer <josch1710@live.de> :
On a T420 pressing the ACPI button for volume control, big scancodes
were emitted. This was causing an overflow, because missing guards.
By default, we will minimize the window when we receive Alt+Tab with a
full-screen keyboard grabbed window to allow the user to escape the
full-screen application.
Some applications like remote desktop clients may want to handle Alt+Tab
themselves, so provide an opt-out via SDL_HINT_ALLOW_ALT_TAB_WHILE_GRABBED=0.
Daniel Gibson
AZERTY keyboard layouts (which are the default layouts in France and Belgium) don't have the number keys (1, 2, ..., 9, 0) in the first row of keys, but ?, &, ?", ', (, -, ?_, ??), = (with small differences between the France and Belgian variants). Numbers are reached via shift.
On Linux and OSX, SDL seems to use the corresponding ISO 8859-1 codes (231 for ?232 for ?tc) as SDL_Keycode (but no SDK_* constants exists for those values!), while on Windows SDL seems to map those keys to SDLK_1, SDLK_2 etc, like you'd get on QWERTY.
I don't know how other platforms behave.
So we have two problems:
1. At least on Linux and OSX invalid/undefined SDL_Keycodes are returned
2. Different platforms behave differently (Windows vs Linux/OSX)
It's unclear what behavior is desired: Should SDL_* constants for those keys be introduced (and Windows behavior changed accordingly)?
Or should all platforms behave like Windows here and use the existing SDLK_1, ..., SDLK_0 keycodes?
This bug on the mailing list:
https://forums.libsdl.org/viewtopic.php?t=11555 (my post about Linux/Windows)
https://forums.libsdl.org/viewtopic.php?t=11573 (Tim Walters discovered the same problem on OSX about 1.5 weeks later).
Adam M.
The keysym.mod field does not reflect the state of the modified keys when processing key down events for the modifier keys themselves. The documentation says that it returns the current key modifiers, but they are not current for key down events involving modifier keys. I interpret "current" to mean "equal to SDL_GetModState() at the instant the event is processed/enqueued".
For example, if you depress the Shift key you get a key down event with .mod == 0. However, .mod should not be 0 because a shift key is down. If you then release the Shift key, you get a key up event with .mod == 0. Neither event reports the modifier key.
If you press Shift and then A, .mod is incorrect (== 0) when Shift is pressed, but is correct later when A is pressed (== KMOD_LSHIFT).
You might say this behavior is deliberate, i.e. keysym.mod is the value /before/ the event, not the current value as documented, but that explanation is incorrect because only key down events behave that way. Key up events correctly give the current value, not the value before the event.
Not only is it inconsistent with itself, I think it makes keyboard processing harder.
The problem is near line 740 in SDL_keyboard.c:
if (SDL_KEYDOWN == type) {
modstate = keyboard->modstate; // SHOULD THIS BE MOVED DOWN?
switch (keycode) {
case SDLK_NUMLOCKCLEAR:
keyboard->modstate ^= KMOD_NUM;
break;
case SDLK_CAPSLOCK:
keyboard->modstate ^= KMOD_CAPS;
break;
default:
keyboard->modstate |= modifier;
break;
}
} else {
keyboard->modstate &= ~modifier;
modstate = keyboard->modstate;
}
In the key down path, modstate (and thus keysym.mod) ends up being the modifier state /before/ the event, but in the key up path modstate ends up being the modifier state /after/ the event. Personally I think the "modstate = keyboard->modstate" line should just be moved after the entire if/else statement, so that keysym.mod always reflects the current state.
Holger Schemel
Summary: This patch adds support for key events for the "rewind" and "fast forward" media keys on the Amazon Fire TV remote control.
How to reproduce the problem: Run Android build of SDL2 application on the Amazon Fire TV (tested with "stick" version) and log key events.
Expected behaviour: Every key pressed on the Fire TV remote control should result in a corresponding key event (pressed/released).
Observed behaviour: Of the bottom row of buttons on the Fire TV remote control, only the "play/pause" (middle) button generates a key event, while the "rewind" (left) and "fast forward" (right) buttons to not generate any event at all.
The attached patch adds support for these two missing buttons/keys.
Note 1: Some missing definitions were added for the already existing key codes SDL_SCANCODE_APP1 and SDL_SCANCODE_APP2 (to keep up the correct order of enumerations / array positions when adding the two new key codes).
Note 2: Definitions in "scancodes_linux.h" and "scancodes_xfree86.h" (to also add support for these keys on other platforms) were added without testing. However, I was unable to find corresponding definitions for these two media keys for Windows and Mac OS X.
Note 3: I have also updated the (broken) link to the USB usage page standard PDF document (comment in "include/SDL_scancode.h").
The internal function SDL_EGL_LoadLibrary() did not delete and remove a mostly
uninitialized data structure if loading the library first failed. A later try to
use EGL then skipped initialization and assumed it was previously successful
because the data structure now already existed. This led to at least one crash
in the internal function SDL_EGL_ChooseConfig() because a NULL pointer was
dereferenced to make a call to eglBindAPI().