X11 has a so-called primary selection, which you can use by marking text and middle-clicking elsewhere to copy the marked text.
There are 3 new API functions in `SDL_clipboard.h`, which work exactly like their clipboard equivalents.
## Test Instructions
* Run the tests (just a copy of the clipboard tests): `$ ./test/testautomation --filter Clipboard`
* Build and run this small application:
<details>
```C
#include <SDL.h>
#include <unistd.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
void print_error(const char *where)
{
const char *errstr = SDL_GetError();
if (errstr == NULL || errstr[0] == '\0')
return;
fprintf(stderr, "SDL Error after '%s': %s\n", where, errstr);
SDL_ClearError();
}
int main()
{
char text_buf[256];
srand(time(NULL));
SDL_Init(SDL_INIT_VIDEO);
print_error("SDL_INIT()");
SDL_Window *window = SDL_CreateWindow("Primary Selection Test", SDL_WINDOWPOS_UNDEFINED,
SDL_WINDOWPOS_UNDEFINED, 400, 400, SDL_WINDOW_SHOWN);
print_error("SDL_CreateWindow()");
SDL_Renderer *renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED);
print_error("SDL_CreateRenderer()");
bool quit = false;
unsigned int do_render = 0;
while (!quit) {
SDL_Event event;
while (SDL_PollEvent(&event)) {
print_error("SDL_PollEvent()");
switch (event.type) {
case SDL_QUIT: {
quit = true;
break;
} case SDL_KEYDOWN: {
switch (event.key.keysym.sym) {
case SDLK_ESCAPE:
case SDLK_q:
quit = true;
break;
case SDLK_c:
snprintf(text_buf, sizeof(text_buf), "foo%d", rand());
SDL_SetClipboardText(text_buf);
print_error("SDL_SetClipboardText()");
printf("clipboard: set_to=\"%s\"\n", text_buf);
break;
case SDLK_v: {
printf("clipboard: has=%d, ", SDL_HasClipboardText());
print_error("SDL_HasClipboardText()");
char *text = SDL_GetClipboardText();
print_error("SDL_GetClipboardText()");
printf("text=\"%s\"\n", text);
SDL_free(text);
break;
} case SDLK_d:
snprintf(text_buf, sizeof(text_buf), "bar%d", rand());
SDL_SetPrimarySelectionText(text_buf);
print_error("SDL_SetPrimarySelectionText()");
printf("primselec: set_to=\"%s\"\n", text_buf);
break;
case SDLK_f: {
printf("primselec: has=%d, ", SDL_HasPrimarySelectionText());
print_error("SDL_HasPrimarySelectionText()");
char *text = SDL_GetPrimarySelectionText();
print_error("SDL_GetPrimarySelectionText()");
printf("text=\"%s\"\n", text);
SDL_free(text);
break;
} default:
break;
}
break;
} default: {
break;
}}
}
// create less noise with WAYLAND_DEBUG=1
if (do_render == 0) {
SDL_RenderPresent(renderer);
print_error("SDL_RenderPresent()");
}
do_render += 1;
usleep(12000);
}
SDL_DestroyRenderer(renderer);
SDL_DestroyWindow(window);
SDL_Quit();
print_error("quit");
return 0;
}
```
</details>
* Use c,v,d,f to get and set the clipboard and primary selection.
* Mark text and middle-click also in other applications.
* For wayland under x:
* `$ mutter --wayland --no-x11 --nested`
* `$ XDG_SESSION_TYPE=wayland SDL_VIDEODRIVER=wayland ./<path_to_test_appl_binary>`
Update the Wayland core protocol spec file and add support for the new axis_value120 event to handle high resolution scroll wheels.
The axis_value120 replaces the axis_discrete event, which is no longer sent as of version 8 of the protocol. Note that unlike the axis_discrete event, no mention in the spec is made regarding how many axis_value120 events may occur per-axis per-frame, so the values are accumulated and committed when the pointer frame event occurs.
Wayland works like SDL's "auto capture" feature already, tracking the mouse
globally only while a drag is occuring, and this is the only way to get mouse
input outside the window.
Setting this flag ourselves lets SDL_CaptureMouse() work in the most common
use case without actually implementing CaptureMouse for the backend, including
SDL's auto capture feature.
Fixes#6010.
We might want to use ssize_t as @Guldoman suggested, but that's a larger internal API change, and still requires casting of the SDL_utf8strnlen() result.
Fixes https://github.com/libsdl-org/SDL/pull/5821
Because we were sending multiple chunks of preedit strings,
`SDL_SendEditingText` was using the old `SDL_TEXTEDITING` event only.
Now if `SDL_HINT_IME_SUPPORT_EXTENDED_TEXT` is enabled, we send the full
string and correctly set the cursor position and selection size.
As of #5703, we call libdecor_dispatch() in Wayland_WaitEventTimeout(),
but this will crash if we don't load libdecor, as
SDL_VideoData::shell.libdecor will be NULL.
Since we don't load libdecor if we don't intend to use it (i.e., if
should_use_libdecor returns false), this results in a crash under KDE in
almost all circumstances.
Don't be fooled by the diff size - this ended up being a big refactor of the
shell surface management, masked only by some helper macros I wrote for the
popup support.
This change makes it so when xdg_decoration is supported, but CSD is requested,
the system bails on xdg support entirely and resets all the windows to use
libdecor instead. This transition isn't pretty, but once it's done it will be
smooth if decorations are an OS toggle since libdecor will take things from
there.
In hindsight, we really should have designed libdecor to be passed a toplevel,
having it manage that for us keeps causing major refactors for _every_ change.
Expose as many emulated display modes as possible. They will currently display stretched to the display's native desktop aspect, but if an application requires a hardcoded resolution, it will work at minimum.
Aside from the change in the emulated display mode list, the Wayland event handling code had to be updated to support separate scaling for the x and y axes, as square pixels are no longer guaranteed.
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