Jan Bujak
I wrote a new driver for my gamepad on Linux. I'd like SDL to support it out-of-box, as currently it just treats it as a generic joystick instead of a gamepad. From what I can see the only way to do that is to either 1) pick one of the already supported controllers' PID, VID and button layouts and have my driver send that (effectively lying that it's something else), or 2) submit a preconfigured, hardcoded mapping to SDL.
Both of those, in my opinion, are silly when we already have the Linux Gamepad Specification which standarizes this:
https://www.kernel.org/doc/html/v4.15/input/gamepad.html
Unfortunately SDL doesn't make use of it currently. So I've took it upon myself to add it; patch is in the attachments.
Basically what the patch does is that if SDL finds no built-it controller mappings for a given joystick it then asks the joystick backend to autodetect it, and that uses the relevant evdev bits to figure out which button/axis is which. (See the specs for more details.)
With this patch applied my own driver for my controller works out-of-box with SDL with no extra configuration and is correctly recognized as a gamepad; this is also going to be the case for any other driver which follows the Linux Gamepad Specification.
Arithmatic operations promote Uint8 to signed int. If the top bit of a
Uint8 is set, and it is left shifted 24 places, then the result is not
representable in a signed 32 bit int. This would be undefined behaviour
on systems where int is 32 bits.
It makes it clearer who owns the memory, and more reasonable to free it on
failure in the creating function.
(and, of course, pacifies static analysis.)
Manuel Alfayate Corchete
On the KMSDRM backend, there is no such thing as a desktop, yet some programs could (and DO) use SDL_GetGlobalMouseState().
So I think its good idea that, in KMSDRM, it returns the same mouse coordinates anyway as SDL_GetMouseState() would return. There is nothing else it could return, as far as I can understand, since there is no desktop anyway.
This small patch does precisely that.
Manuel Alfayate Corchete
The KMSDRM backend was doing things wrong because of some small (but important) misconceptions on how KMS/DRM works: to implement a largely broken non-vsync refresh mechanism, the SwapWindow() function was issuing new pageflips before previous ones had completed, thus causing EBUSY returns, buffer mismanagement, etc... resulting in general breakage on vsync disabling from apps, that would not allow vsync to work again without KMSDRM video re-initialization.
To further clarify, on most DRM drivers async pageflips are NOT working nowadays, so all issued pageflips will complete on next VBLANK, NOT ASAP (calling drmModePageFlip() with the DRM_MODE_PAGE_FLIP_ASYNC flag will return error).
The old code was assuming that can just issue a synchronous (=on VBLANK) pageflip and then pass a 0 timeout to the pull() function so we do not wait for the pageflip event, thinking that this will lead to correct non-vsynced screen updates from the program: That is plain wrong.
Each pageflip has to be waite before issuing a new one, ALWAYS. And if we do not support ASYNC pageflips on the DRM driver level, then we are forced to wait for the next VBLANK. There is no way around it.
I have also added many comments on the KMSDRM code. This is needed for future reference for me or others who may need to look at this code: KMS/DRM terminology regarding what SYNC and ASYNC mean in pageflip terms, and where to do certain things and why, is not trivial. It is not desirable or possible to invest time on researching the same concepts every time there is need to dive into this code. So please leave all these comments in the patch.
1. Comment that SDL_SetThreadPriority will make any necessary system changes when applying priority.
2. Add a hint to override SDL's default behavior for scheduler policy.
3. Modify the pthreads SDL_SetThreadPriority so that instead of just using the current thread scheduler policy it will change it to a policy that should work best for the requested priority.
4. Add hint checks in SDL_SetThreadPriority so that #3 can be overridden if desired.
5. Modify the Linux SDL_SetThreadPriority so that in the case that policy, either by SDL defaults or from the hint, is a realtime policy it uses the realtime rtkit API.
6. Prior to calling rtkit on Linux make the necessary thread state changes that rtkit requires. Currently this is done every time as it isn't expected that SDL_SetThreadPriority will be called repeatedly for a thread.
michaeljosephmaltese
Display ends up taking only 1/4 of the screen area. It needs to call "setWantsBestResolutionOpenGLSurface:highdpi", like when creating a window the normal way.
wengxt
Due to the new major fcitx version is coming close, the existing code need to be ported to use new Fcitx dbus interface.
The new dbus interface is supported by both fcitx 4 and 5, and has a good side effect, which is that it will work with flatpak for free. Also the patch remove the dependency on fcitx header. Instead, it just hardcodes a few enum value in the code so need to handle the different header for fcitx4 or 5.
meyraud705
'SDL_Windows::driverdata' of a Wayland window is allocated by calloc in 'Wayland_CreateWindow' but freed by SDL_free in 'Wayland_DestroyWindow'.
meyraud705
I see how the documentation is confusing. I think that the choice of the axis is an implementation detail. The documentation should state the goal of this value, so I propose this wording:
"Use this value to play an effect on the steering wheel axis. This provides
better compatibility across platforms and devices as SDL will guess the
correct axis."
Value could even be renamed 'SDL_HAPTIC_STEERING_AXIS'.
For Linux, sending an effect on the X axis with a Logitech wheel works. Others brands don't have driver for Linux as far as I know.
This is only supported on PulseAudio. You can set a description when opening
your audio device that will show up in pauvcontrol, which lets you set
per-stream volume levels.
Fixes Bugzilla #4801.
dark_sylinc
Trying to build SDL with VS2019 using CMake will encounter a linking error
More specifically:
1>SDL_string.obj : error LNK2019: unresolved external symbol memset referenced in function SDL_vsnprintf_REAL
* 8BitDo N30 Pro 2
* 8BitDo SN30 Gamepad
* 8BitDo SN30 Pro+
* 8BitDo Zero 2
* SZMY-POWER PC Gamepad
* ThrustMaster eSwap PRO Controller
* ZEROPLUS P4 Wired Gamepad
In additional, all 8BitDo controllers use SDL_HINT_GAMECONTROLLER_USE_BUTTON_LABELS to have the correct mapping based on user preferences.
This patch removes deferred error string formatting: now we do it during
SDL_SetError(), so there's no limit on printf-style arguments used.
Also removes stub for managing error string translations; we don't have the
facilities to maintain that and the way we set arbitrary error strings
doesn't really make this practical anyhow.
Since the final error string is set right away and unique to the thread,
we no longer need a static buffer for legacy SDL_GetError(), and we don't
have to allocate 5x 128-byte argument fields per-thread. Also, since we now
use SDL_vsnprintf instead of parsing the format string ourselves, there's a
lot of code deleted and we have access to more robust formatting powers now.
This does mean the final error strings can't be more than 128 bytes, down
from the theoretical maximum of around 768, but I think this is probably okay.
They might truncate but they will always be null-terminated!
Fixes Bugzilla #5092.
The joystick layer can't necessarily give us perfect centering, but we know
that the game controller level has logical absolute idle positions that have
nothing to do with the physical device.
So send game controller events to make it look like the device is completely
untouched before sending the final removal event.
This driver supports the Razer Atrox Arcade Stick
Some of the quirks of this driver, inherent in Windows Gaming Input:
* There will never appear to be controllers connected at startup. You must support hot-plugging in order to see these controllers.
* You can't read the state of the guide button
* You can't get controller events in the background
meyraud705
On line 220 of SDL_hidapi_xbox360.c https://hg.libsdl.org/SDL/file/4608f0e6e8e3/src/joystick/hidapi/SDL_hidapi_xbox360.c#l220
if (!XINPUTGETSTATE(user_index, &xinput_state[user_index].state) == ERROR_SUCCESS) {
logical not is only applied to the left hand side of this comparison.
I think you mean:
if (XINPUTGETSTATE(user_index, &xinput_state[user_index].state) != ERROR_SUCCESS) {
