Wayland doesn't support mode switching, however Wayland compositors can support the wp_viewporter protocol, which allows for the mapping of arbitrarily sized buffer regions to output surfaces. Use this functionality, when available, for fullscreen output when using non-native display modes and/or when dealing with scaled desktops, which can incur significant overdraw without this extension.
This also allows for the exposure of arbitrarily sized, emulated display modes, which can be useful for legacy compatability.
1. Mod index values are (mostly) constant, so can be done with xkb_state_new
2. Mods can change without the group changing, avoid remap events if possible
Lastly, as a bonus, I added braces to the locale check, because I was nearby.
Previous to this commit, key repeats events were typically generated when
pumping events, based on the time of when the events are pumped. However,
if an application doesn't call `SDL_PumpEvents` for some seconds, this time
can be multiple seconds in the future compared to the actual key up event time,
and generates key repeats even if a key was pressed only for an instant.
In practice, this can happen when the user presses a key which causes the
application to do something without pumping events (e.g. load a level).
In Crispy Doom & PrBoom+, when the user presses the key bound to "Restart
level/demo", the game doesn't pump events during the "screen melt" effect,
and the level is restarted multiple times due to spurious repeats.
To fix this, if the key up event is among the events to be pumped, we generate
the key repeats there, since in the Wayland callback we receive the time when
the key up event happened. Otherwise, we know no key up event happened and we
can generate as many repeats as necessary after pumping.
Signed-off-by: Joan Bruguera <joanbrugueram@gmail.com>
Refactorization with no functional changes.
Instead of `next_repeat_ms` containing a timestamp based on SDL ticks, we make
it zero-based relative to the key press time, and we store the key press time in
SDL ticks in a new field.
This refactorization is groundwork for future commits which need to use the
key press and release timestamps provided by the Wayland API, which are also
expressed in milliseconds, but whose base does not match the one for SDL ticks.
Signed-off-by: Joan Bruguera <joanbrugueram@gmail.com>
If `repeat_info->next_repeat_ms` overflows, many key presses will be generated.
In the worst case, `now = 0xFFFFFFFFU` and the loop will never terminate.
Rearrange the comparison in order to gracefully handle the overflow case.
Signed-off-by: Joan Bruguera <joanbrugueram@gmail.com>
Add a new flag to avoid suppressing EINTR in SDL_IOReady(). Pass the
flag in WaitEventTimeout() to ensure that a SIGINT will wake up
SDL_WaitEvent() without another event coming in.
We can have spurious wakeups in WaitEventTimeout() due to Wayland events
that don't end up causing us to generate an SDL event. Fortunately for us,
SDL_WaitEventTimeout_Device() handles this situation properly by calling
WaitEventTimeout() again with an adjusted timeout.
Wayland provides the prepare_read()/read_events() family of APIs for
reading from the display fd in a deadlock-free manner across multiple
threads in a multi-threaded application. Let's use those instead of
trying to roll our own solution using a mutex.
This fixes an issue where a call to SDL_GL_SwapWindow() doesn't swap
buffers if it happens to collide with SDL_PumpEvents() in the main
thread. It also allows coexistence with other code or toolkits in
our process that may want read and dispatch events themselves.
wl_display_dispatch() will block if there are no events available, and
while we try to avoid this by using SDL_IOReady() to verify there are
events before calling it, there is a race condition between
SDL_IOReady() and wl_display_dispatch() if multiple threads are
involved.
This is made more likely by the fact that SDL_GL_SwapWindow() calls
wl_display_dispatch() if vsync is enabled, in order to wait for frame
events. Therefore any program which pumps events on a different thread
from SDL_GL_SwapWindow() could end up blocking in one or other of them
until another event arrives.
This change fixes this by wrapping wl_display_dispatch() in a new mutex,
which ensures only one thread can compete for wayland events at a time,
and hence the SDL_IOReady() check should successfully prevent either
from blocking.
There were a few places throughout the SDL code where values were
clamped using SDL_min() and SDL_max(). Now that we have an SDL_clamp()
macro, use this instead.
This fixes a crash on pressing keyboard button when compositor sends
zero as repeat rate, indicating that key repeat should be disabled.
From Wayland protocol spec:
> Negative values for either rate or delay are illegal. A rate of zero
> will disable any repeating (regardless of the value of delay).
As of [1], SDL now compiles with a warning in SDL_waylandevents.c on
32-bit systems under gcc 10.3.0:
/tmp/SDL/src/video/wayland/SDL_waylandevents.c: In function 'seat_handle_capabilities':
/tmp/SDL/src/video/wayland/SDL_waylandevents.c:958:22: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
958 | SDL_AddTouch((SDL_TouchID)seat, SDL_TOUCH_DEVICE_DIRECT, "wayland_touch");
| ^
/tmp/SDL/src/video/wayland/SDL_waylandevents.c:964:22: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
964 | SDL_DelTouch((SDL_TouchID)seat);
| ^
This is due to SDL_TouchID always being 32-bit, but seat being a pointer
which is (obviously) only 32-bit on 32-bit systems. The conversion is
therefore harmless, so silence it with an extra cast via intptr_t.
This is what the cocoa backend does (and is similar to what the Win32
backend does, except with size_t).
Fixes: 03c19efbd1 ("Added support for multiple seats with touch input on Wayland")
[1]: 03c19efbd1
Wayland video subsystem uses a mix of libc and SDL function.
This patch switches libc functions to SDL ones and fixes a mismatch in memory
allocation/dealoccation of SDL_Cursor in SDL_waylandmouse.c (calloc on line 201
and SDL_free on line 313) which caused memory corruption if custom memory
allocator where provided to SDL.
There is no guarantee on what order the Wayland interfaces will come in, but the
callbacks were assuming that wl_data_device_manager would could before wl_seat.
This would cause certain desktops to not have any data_device to work with,
meaning certain features like the clipboard would silently no-op.
Note that this is purely to make it possible to enter text that requires
composition - for example, before this commit Kanji input didn't work at all.
The big problem this still has is that we need the window position, and this is
still not implemented. Once we have this information we can do the equivalent
of XTranslateCoordinates to put the rectangle where we want it.
Unlike Mutter and Sway, KWin actually checks the serial passed in
wl_pointer_set_cursor(). The serial provided is supposed to be the
serial of the pointer enter event, but We were always passing 0.
This caused KWin to drop our requests to hide the cursor.
Thanks to the KDE folks for spotting this in my debug logs.
Fixes#3576
SDL_SetKeyboardFocus(NULL) will lift any keys still pressed when keyboard focus
leaves the window, but then key repeat comes behind our backs and presses the
key down again. This results in an infinite stream of SDL_KEYDOWN events when
focus leaves the window with a key down (particularly noticeable with Alt+Tab).
Wayland compositors seem to have standardized on 10 units per "wheel tick" for
continuous scroll events, so we need to convert these axis values to ticks by
dividing by 10 before reporting them in SDL_MOUSEWHEEL events.
Hiding the cursor doesn't appear to work reliably on GNOME when another window
steals mouse focus right as we call SDL_ShowCursor(SDL_DISABLE). This can happen
when the keyboard shortcut inhibition permission prompt appears in response to a
call to SDL_SetRelativeMouseMode() with SDL_HINT_GRAB_KEYBOARD=1. The result is
that the default cursor is stuck locked in position and visible on screen
indefinitely.
By redrawing the cursor on pointer focus enter, the cursor now disappears upon
the first mouse motion event. It's not perfect but it's way better than the
current behavior.
Use zwp_keyboard_shortcuts_inhibit_manager_v1 to allow SDL applications
to capture system keyboard shortcuts like Alt+Tab when keyboard grab is
enabled via SDL_HINT_GRAB_KEYBOARD.