Now we render directly to the window, scaling as appropriate. This fixes some
concerns the render target introduced, like the quality of the final scaled
output, how to step outside of the logical size temporarily to draw some
things sharply at the native resolution, and loss of sub-pixel precision.
Fixes#8736.
Handle named and custom cursor scaling in a cleaner manner, and account for edge cases where named cursor sizes may not exactly match the required size.
Modern kernels (v5.8+) allow non-root usage of drmDropMaster(), so
we can hold on to our fd after dropping master on it. This fixes
populating drm_fd in the KMSDRM SysWMinfo when using Vulkan.
Also add a missing error check for open() while we're here
By writing the fxc and dxc output to a temporary file and then
converting that temporary file to the desired filename, we avoid
the incompatible semantics of sed -i on GNU systems (sed -i does not
create a backup filename, and does not take an argument unless it is
"bundled") and macOS (sed -i requires an argument, possibly empty).
Resolves: https://github.com/libsdl-org/SDL/issues/10878
Signed-off-by: Simon McVittie <smcv@debian.org>
We require stdbool.h in the build environment, so we might as well use the plain bool type.
If your environment doesn't have stdbool.h, this simple replacement will suffice:
typedef signed char bool;
We want `$USE_FXC` to default to the result of evaluating the variable
`$HAVE_FXC`, not the literal string `HAVE_FXC`, and the same for dxc.
Signed-off-by: Simon McVittie <smcv@debian.org>
We always need to destroy the hotplug loop and its associated resources
(if created) before we can deinitialize and unload the Pipewire library.
In the happy path where everything worked correctly, this means we will
call hotplug_loop_destroy() twice (once from PIPEWIRE_DeinitializeStart()
and a second time from PIPEWIRE_Deinitialize()), but that's OK, because
it's idempotent and so will do nothing the second time.
In error-handling code paths, this avoids needing to remember to call
hotplug_loop_destroy() explicitly, which should make it easier to avoid
bugs like #10787.
Signed-off-by: Simon McVittie <smcv@collabora.com>
This was the only API that broke the "GetNumThings" convention
used elsewhere, so renaming it helps with consistency.
Adding "logical cores" to the name also makes it a bit
more immediately obvious what the count actually represents.
This had the unfortunate side-effect of blocking if you tried to write too much. Instead you can use SDL_GetProcessInput() and handle SDL_IO_STATUS_NOT_READY as needed.
Fixes https://github.com/libsdl-org/SDL/issues/10834
Also marked the existing functions as unsafe, as they can cause crashes if used in multi-threaded applications.
As a bonus, since the new functions are hashtable based, hint environment lookups are much faster.
Also added SDL_PROP_IOSTREAM_FILE_DESCRIPTOR_NUMBER and refactored the internal API to be able to create SDL_IOStream objects from native file handles.
In some cases, such as when recreating a window during renderer initialization, a failure can leave the window in a state where the internal structure has already been freed, but the higher level window object needs to be destroyed separately. Check that the internal handle is valid before attempting to access any data during destruction.
Allows for graceful failure instead of a crash during cleanup if renderer creation fails.
Use doubles and apply an offset to account for rounding errors due to Wayland scale increments being in units of 1/120. This fixes the backbuffer size calculations with certain combinations of size/scale values, and future-proofs the Wayland backend, as 32-bit floats become increasingly error-prone with larger dimensions and/or scale factors.
The conversion formula is now point->pixel->point round trip safe as well.
This used a tiny stack, which apparently upsets Blender for various
technical reasons. Instead, just use the default stack size, which should
give it plenty of space to work.
If the thread failed to create, we would then wait on a semaphore that would
never trigger, so don't do that anymore!
Fixes#10806.
GameInput currently has a bug with keys stuck on focus change, and crashes on initialization on some systems, so we'll disable it until these issues are fixed.
@smcv may have found the root cause of the pipewire thread crash, so removing the pipewire client version check to re-enable use of pipewire in older container runtimes.
hotplug_loop_init() calls pw_context_new(), which creates a thread
internally (for the "data loop"). It also creates a thread of its own,
the `hotplug_loop`.
Both of these threads are running code from libpipewire, so before we
can allow the Pipewire library to be unloaded, we need to destroy
the context with pw_context_destroy() and destroy the `hotplug_loop`
with pw_thread_loop_destroy().
Resolves: https://github.com/libsdl-org/SDL/issues/10787
Signed-off-by: Simon McVittie <smcv@collabora.com>
On most Unix platforms supported by SDL, the canonical name used to load
a library at runtime includes its ABI major version, and the name
without a version is not guaranteed to exist on non-developer systems.
libX11-xcb.so.1 is correct on Linux, and probably on other Unix
platforms like FreeBSD.
A notable exception is OpenBSD, which apparently does not use
ABI-suffixed names, so continue to use libX11-xcb.so there.
Signed-off-by: Simon McVittie <smcv@collabora.com>
When debugging crash reports, it's helpful to know which thread is
associated with which external library.
Linux limits the length of a thread name to 15 bytes (not including the
zero-termination), so abbreviate Pipewire to "pw" and hotplug to "plug"
to fit the desired information into the allowed space.
Signed-off-by: Simon McVittie <smcv@collabora.com>
We make sure we initialize XInput first, so that anything checking whether it's enabled gets a valid result based on whether we were able to load it or not.
- CreateEventEx() is guarded by _WIN32_WINNT >= 0x0600:
In SDL_gpu_d3d12.c, include core/windows/SDL_windows.h
that defines _WIN32_WINNT properly to account for that
- DXGIInfoQueue stuff is not available in all toolchains
such as mingw-w64 version 8.0.3
- SDL_gpu_d3d11.c: _WIN32 is always defined by MinGW, as
is the case for all windows-targeting compilers, so it
doesn't guarantee absence of DXGIInfoQueue stuff:
rely on __IDXGIInfoQueue_INTERFACE_DEFINED__, as it is
done elsewhere.
Fixes: https://github.com/libsdl-org/SDL/issues/10705 .
Allow setting a parent/child relationship on toplevel windows, which allows raising sets of windows together, and allows child windows to always float above their parents.
Modal windows are now set by setting the parent, then toggling modal status, as the previous interface duplicated functionality now handled by SDL_SetWindowParent().
The default value of MAX_FRAMES_IN_FLIGHT (3) may be less than the
minImageCount returned by vkGetPhysicalDeviceSurfaceCapabilitiesKHR() on
some setups. For example, the Intel IVB Vulkan driver on Wayland returns
a minImageCount of 4, resulting in the following validation warning:
VUID-VkSwapchainCreateInfoKHR-presentMode-02839(ERROR / SPEC): msgNum: -76493605 - Validation Error: [ VUID-VkSwapchainCreateInfoKHR-presentMode-02839 ] | MessageID = 0xfb70ccdb | vkCreateSwapchainKHR(): pCreateInfo->minImageCount 3, which is outside the bounds returned by vkGetPhysicalDeviceSurfaceCapabilitiesKHR() (i.e. minImageCount = 4, maxImageCount = 0). The Vulkan spec states: If presentMode is not VK_PRESENT_MODE_SHARED_DEMAND_REFRESH_KHR nor VK_PRESENT_MODE_SHARED_CONTINUOUS_REFRESH_KHR, then minImageCount must be greater than or equal to the value returned in the minImageCount member of the VkSurfaceCapabilitiesKHR structure returned by vkGetPhysicalDeviceSurfaceCapabilitiesKHR for the surface (https://www.khronos.org/registry/vulkan/specs/1.3-extensions/html/vkspec.html#VUID-VkSwapchainCreateInfoKHR-presentMode-02839)
Objects: 0
Use the minimum image count in that case, as it's as close as we'll get
to our preferred value. Note also that, unlike maxImageCount,
minImageCount is never 0 (the spec states it is always at least 1), so
we don't need a similar check to see if it applies.
Signed-off-by: David Gow <david@ingeniumdigital.com>
The `colorAttachmentDescriptions` field of `SDL_GPUGraphicsPipelineAttachmentInfo` should be marked `const`,
similarly to the `vertexBindings` and `vertexAttributes` fields of `SDL_GPUVertexInputState`.
Using the @() syntax to construct an NSString assumes the parenthesized
pointer is null-terminated, but the Metal shader source included in
render/sdlgpu/shaders/metal.h is not null-terminated.
Quoting the clang documentation on Objective-C literals:
When the type of the parenthesized expression is (char *) or (const
char *), the result of the boxed expression is a pointer to an
NSString object containing equivalent character data, which is
assumed to be ‘\0’-terminated and UTF-8 encoded.
Because the @() syntax assumes null-termination, it may read garbage
data after the shader source (up to the next null byte), which can then
cause the Metal shader compiler to fail. To prevent this, instead of
using the @() boxing syntax, we explicitly construct an NSString using
the string length passed by the caller.
These functions had special cases for a few BC formats, but all
block-compressed formats should need the same logic. Furthermore they
weren't handling the sRGB variants of those formats.
OutputDebugString and fprintf(stderr) (of mslibc) both output
to the debug window of Visual Studio.
In other debuggers (e.g. RAD), this does not happen.
To avoid double output, this commit always uses WriteFile/WriteConsole.
Most SDL functions used to indicate success or failure using an int return code. These functions have been changed to return SDL_bool.
Here is a coccinelle patch to change code that previously compared the return value to 0 and changes it to a boolean test:
@ bool_return_type @
identifier func =~ "^(SDL_AddEventWatch|SDL_AddHintCallback|SDL_AddSurfaceAlternateImage|SDL_AddVulkanRenderSemaphores|SDL_BindAudioStream|SDL_BindAudioStreams|SDL_BlitSurface|SDL_BlitSurface9Grid|SDL_BlitSurfaceScaled|SDL_BlitSurfaceTiled|SDL_BlitSurfaceTiledWithScale|SDL_BlitSurfaceUnchecked|SDL_BlitSurfaceUncheckedScaled|SDL_CaptureMouse|SDL_ClearAudioStream|SDL_ClearClipboardData|SDL_ClearComposition|SDL_ClearError|SDL_ClearProperty|SDL_ClearSurface|SDL_CloseIO|SDL_CloseStorage|SDL_ConvertAudioSamples|SDL_ConvertEventToRenderCoordinates|SDL_ConvertPixels|SDL_ConvertPixelsAndColorspace|SDL_CopyFile|SDL_CopyProperties|SDL_CopyStorageFile|SDL_CreateDirectory|SDL_CreateStorageDirectory|SDL_CreateWindowAndRenderer|SDL_DateTimeToTime|SDL_DestroyWindowSurface|SDL_DetachVirtualJoystick|SDL_DisableScreenSaver|SDL_EnableScreenSaver|SDL_EnumerateDirectory|SDL_EnumerateProperties|SDL_EnumerateStorageDirectory|SDL_FillSurfaceRect|SDL_FillSurfaceRects|SDL_FlashWindow|SDL_FlipSurface|SDL_FlushAudioStream|SDL_FlushRenderer|SDL_GL_DestroyContext|SDL_GL_GetAttribute|SDL_GL_GetSwapInterval|SDL_GL_LoadLibrary|SDL_GL_MakeCurrent|SDL_GL_SetAttribute|SDL_GL_SetSwapInterval|SDL_GL_SwapWindow|SDL_GetAudioDeviceFormat|SDL_GetAudioStreamFormat|SDL_GetCameraFormat|SDL_GetClosestFullscreenDisplayMode|SDL_GetCurrentRenderOutputSize|SDL_GetCurrentTime|SDL_GetDXGIOutputInfo|SDL_GetDateTimeLocalePreferences|SDL_GetDisplayBounds|SDL_GetDisplayUsableBounds|SDL_GetGDKDefaultUser|SDL_GetGDKTaskQueue|SDL_GetGamepadSensorData|SDL_GetGamepadTouchpadFinger|SDL_GetHapticEffectStatus|SDL_GetJoystickBall|SDL_GetMasksForPixelFormat|SDL_GetPathInfo|SDL_GetRectUnion|SDL_GetRectUnionFloat|SDL_GetRenderClipRect|SDL_GetRenderColorScale|SDL_GetRenderDrawBlendMode|SDL_GetRenderDrawColor|SDL_GetRenderDrawColorFloat|SDL_GetRenderLogicalPresentation|SDL_GetRenderLogicalPresentationRect|SDL_GetRenderOutputSize|SDL_GetRenderSafeArea|SDL_GetRenderScale|SDL_GetRenderVSync|SDL_GetRenderViewport|SDL_GetSensorData|SDL_GetStorageFileSize|SDL_GetStoragePathInfo|SDL_GetSurfaceAlphaMod|SDL_GetSurfaceBlendMode|SDL_GetSurfaceClipRect|SDL_GetSurfaceColorKey|SDL_GetSurfaceColorMod|SDL_GetTextInputArea|SDL_GetTextureAlphaMod|SDL_GetTextureAlphaModFloat|SDL_GetTextureBlendMode|SDL_GetTextureColorMod|SDL_GetTextureColorModFloat|SDL_GetTextureScaleMode|SDL_GetTextureSize|SDL_GetWindowAspectRatio|SDL_GetWindowBordersSize|SDL_GetWindowMaximumSize|SDL_GetWindowMinimumSize|SDL_GetWindowPosition|SDL_GetWindowRelativeMouseMode|SDL_GetWindowSafeArea|SDL_GetWindowSize|SDL_GetWindowSizeInPixels|SDL_GetWindowSurfaceVSync|SDL_HideCursor|SDL_HideWindow|SDL_Init|SDL_InitHapticRumble|SDL_InitSubSystem|SDL_LoadWAV|SDL_LoadWAV_IO|SDL_LockAudioStream|SDL_LockProperties|SDL_LockSurface|SDL_LockTexture|SDL_LockTextureToSurface|SDL_MaximizeWindow|SDL_MinimizeWindow|SDL_MixAudio|SDL_OpenURL|SDL_OutOfMemory|SDL_PauseAudioDevice|SDL_PauseAudioStreamDevice|SDL_PauseHaptic|SDL_PlayHapticRumble|SDL_PremultiplyAlpha|SDL_PremultiplySurfaceAlpha|SDL_PushEvent|SDL_PutAudioStreamData|SDL_RaiseWindow|SDL_ReadStorageFile|SDL_ReadSurfacePixel|SDL_ReadSurfacePixelFloat|SDL_RegisterApp|SDL_ReloadGamepadMappings|SDL_RemovePath|SDL_RemoveStoragePath|SDL_RemoveTimer|SDL_RenamePath|SDL_RenameStoragePath|SDL_RenderClear|SDL_RenderCoordinatesFromWindow|SDL_RenderCoordinatesToWindow|SDL_RenderFillRect|SDL_RenderFillRects|SDL_RenderGeometry|SDL_RenderGeometryRaw|SDL_RenderLine|SDL_RenderLines|SDL_RenderPoint|SDL_RenderPoints|SDL_RenderPresent|SDL_RenderRect|SDL_RenderRects|SDL_RenderTexture|SDL_RenderTexture9Grid|SDL_RenderTextureRotated|SDL_RenderTextureTiled|SDL_RequestAndroidPermission|SDL_RestoreWindow|SDL_ResumeAudioDevice|SDL_ResumeAudioStreamDevice|SDL_ResumeHaptic|SDL_RumbleGamepad|SDL_RumbleGamepadTriggers|SDL_RumbleJoystick|SDL_RumbleJoystickTriggers|SDL_RunHapticEffect|SDL_SaveBMP|SDL_SaveBMP_IO|SDL_SendAndroidMessage|SDL_SendGamepadEffect|SDL_SendJoystickEffect|SDL_SendJoystickVirtualSensorData|SDL_SetAppMetadata|SDL_SetAppMetadataProperty|SDL_SetAudioDeviceGain|SDL_SetAudioPostmixCallback|SDL_SetAudioStreamFormat|SDL_SetAudioStreamFrequencyRatio|SDL_SetAudioStreamGain|SDL_SetAudioStreamGetCallback|SDL_SetAudioStreamInputChannelMap|SDL_SetAudioStreamOutputChannelMap|SDL_SetAudioStreamPutCallback|SDL_SetBooleanProperty|SDL_SetClipboardData|SDL_SetClipboardText|SDL_SetCursor|SDL_SetFloatProperty|SDL_SetGamepadLED|SDL_SetGamepadMapping|SDL_SetGamepadPlayerIndex|SDL_SetGamepadSensorEnabled|SDL_SetHapticAutocenter|SDL_SetHapticGain|SDL_SetJoystickLED|SDL_SetJoystickPlayerIndex|SDL_SetJoystickVirtualAxis|SDL_SetJoystickVirtualBall|SDL_SetJoystickVirtualButton|SDL_SetJoystickVirtualHat|SDL_SetJoystickVirtualTouchpad|SDL_SetLinuxThreadPriority|SDL_SetLinuxThreadPriorityAndPolicy|SDL_SetLogPriorityPrefix|SDL_SetMemoryFunctions|SDL_SetNumberProperty|SDL_SetPaletteColors|SDL_SetPointerProperty|SDL_SetPointerPropertyWithCleanup|SDL_SetPrimarySelectionText|SDL_SetRenderClipRect|SDL_SetRenderColorScale|SDL_SetRenderDrawBlendMode|SDL_SetRenderDrawColor|SDL_SetRenderDrawColorFloat|SDL_SetRenderLogicalPresentation|SDL_SetRenderScale|SDL_SetRenderTarget|SDL_SetRenderVSync|SDL_SetRenderViewport|SDL_SetScancodeName|SDL_SetStringProperty|SDL_SetSurfaceAlphaMod|SDL_SetSurfaceBlendMode|SDL_SetSurfaceColorKey|SDL_SetSurfaceColorMod|SDL_SetSurfaceColorspace|SDL_SetSurfacePalette|SDL_SetSurfaceRLE|SDL_SetTLS|SDL_SetTextInputArea|SDL_SetTextureAlphaMod|SDL_SetTextureAlphaModFloat|SDL_SetTextureBlendMode|SDL_SetTextureColorMod|SDL_SetTextureColorModFloat|SDL_SetTextureScaleMode|SDL_SetThreadPriority|SDL_SetWindowAlwaysOnTop|SDL_SetWindowAspectRatio|SDL_SetWindowBordered|SDL_SetWindowFocusable|SDL_SetWindowFullscreen|SDL_SetWindowFullscreenMode|SDL_SetWindowHitTest|SDL_SetWindowIcon|SDL_SetWindowKeyboardGrab|SDL_SetWindowMaximumSize|SDL_SetWindowMinimumSize|SDL_SetWindowModalFor|SDL_SetWindowMouseGrab|SDL_SetWindowMouseRect|SDL_SetWindowOpacity|SDL_SetWindowPosition|SDL_SetWindowRelativeMouseMode|SDL_SetWindowResizable|SDL_SetWindowShape|SDL_SetWindowSize|SDL_SetWindowSurfaceVSync|SDL_SetWindowTitle|SDL_SetiOSAnimationCallback|SDL_ShowAndroidToast|SDL_ShowCursor|SDL_ShowMessageBox|SDL_ShowSimpleMessageBox|SDL_ShowWindow|SDL_ShowWindowSystemMenu|SDL_StartTextInput|SDL_StartTextInputWithProperties|SDL_StopHapticEffect|SDL_StopHapticEffects|SDL_StopHapticRumble|SDL_StopTextInput|SDL_SyncWindow|SDL_TimeToDateTime|SDL_TryLockMutex|SDL_TryLockRWLockForReading|SDL_TryLockRWLockForWriting|SDL_TryWaitSemaphore|SDL_UnlockAudioStream|SDL_UpdateHapticEffect|SDL_UpdateNVTexture|SDL_UpdateTexture|SDL_UpdateWindowSurface|SDL_UpdateWindowSurfaceRects|SDL_UpdateYUVTexture|SDL_Vulkan_CreateSurface|SDL_Vulkan_LoadLibrary|SDL_WaitConditionTimeout|SDL_WaitSemaphoreTimeout|SDL_WarpMouseGlobal|SDL_WriteStorageFile|SDL_WriteSurfacePixel|SDL_WriteSurfacePixelFloat)$";
@@
(
func(
...
)
- == 0
|
- func(
+ !func(
...
)
- < 0
|
- func(
+ !func(
...
)
- != 0
|
- func(
+ !func(
...
)
- == -1
)
On Emscripten without pthreads, this would fail because SDL can't spin the
audio device thread, and the dummy backend didn't manage a thread itself.
With this patch, we use setInterval to fire the usual audio thread iterators
between iterations of the Emscripten mainloop on the main thread.
Fixes#10573.
This was causing crashes in IGameInput_RegisterSystemButtonCallback(), presumably on older systems with runtimes using a different function signature. We'll just disable it for now until the GameInput runtime has stabilized and we can tell when it's safe to use.
This is undocumented since the individual flags are separate window creation properties, but it's useful to have a shared definition for this, which is used internally and for migrating code from SDL2.
src/video/wayland/SDL_waylanddatamanager.c
Log data + primary_selection _offer_receive
src/video/wayland/SDL_waylandevents.c + SDL_waylanddatamanager.h
Log data + primary_selection events
Split FILE vs TEXT events : booleans has_mime_ text + file
Handle text/plain;charset=utf-8 data offer
This changes the API in various ways, and updates the backends for this.
Overall, this is a massive simplification of the API, as most future backends
can't support the previously-offered API.
This also removes the testautomation pen code (not only did these interfaces
change completely, it also did something no other test did: mock the internal
API), and replaces testpen.c with a different implementation (the existing
code was fine, it was just easier to start from scratch than update it).
This is now being done at a higher level, so we don't want to duplicate it here.
Fixes the mouse cursor staying hidden if you enable relative mode, alt-tab away and then alt-tab back.
Require more than one warp to the window center within a certain timespan (currently 30ms, but can be tweaked) to better avoid erroneously entering warp emulation mode.
This also correctly resets the warp emulation mode activation if the window loses and regains focus.
When debugging a GUI application in Visual Studio,
text printed with fprintf(stderr) will also be sent to the debug stream.
When buiding SDL with SDL_LIBC=ON, this patch makes logging skip
OutputDebugString and rely on fprintf(stderr) to send the text to
the debugger.
If there are bugs it's possible that the window pointer is invalid. Double check it before sending the application events and potentially dereferencing it.
This showed up in https://github.com/libsdl-org/SDL/issues/10494 as a window getting mouse focus as it was being destroyed and then crashing later when mouse focus was set to a different window.
This adds functions to query the keymap:
* SDL_GetCurrentKeymap()
* SDL_GetKeymapKeycode()
* SDL_GetKeymapScancode()
* SDL_ReleaseKeymap()
and these are distinct from the function to query the event keycode associated with a scancode, which might be affected by SDL_HINT_KEYCODE_OPTIONS.
Also added an SDL_bool parameter to SDL_GetKeyName() and SDL_GetKeyFromName() to enable upper case handling of the name.
It turns out that the non-Latin keyboards (Russian, Thai, Greek, etc.) are almost all QWERTY layout plus native language labels. Feedback from users is that they expect to see the ASCII keycodes and key names when using those keyboards, so we'll enable this option by default.
Using the shifted versions of keys for the key names doesn't make any sense on the Thai keyboard. Thai keyboards are QWERTY plus Thai characters, so let's use the ASCII key names.
SDL_Keycode is defined as the unshifted key on the keyboard, but the key name is defined as the letter printed on that key, which is usually the shifted capital letter.
Fixes https://github.com/libsdl-org/SDL/issues/5836
SDL_Log() no longer prints a log prefix by default for SDL_LOG_PRIORITY_INFO and below. The log prefixes can be customized with SDL_SetLogPriorityPrefix().
This makes the subsystem thread-safe, more performant, and cleans up the code a little.
Also removed SDL_HINT_WINDOWS_FORCE_MUTEX_CRITICAL_SECTIONS, since setting this hint programmatically initializes properties, which creates a lock, so we can't check hints while creating locks. The slim reader-writer locks have been the default for ages and are solid, so we'll just use those when available.
Allow multiple bootstrap entries for a single video driver with the same name, which internally allows preferential and fallback init conditions while hiding the implementation details from applications (e.g. applications will just see "wayland", regardless of whether it's using the preferred or fallback driver list entry).
If a driver is requested, all instances of it in the list will be tried before reporting failure, and client applications programmatically enumerating the video drivers will be presented with a deduplicated list of entries.
Wayland has a myriad of unresolved problems regarding surface suspension
blocking forever in QueuePresent/SwapBuffers when occludedand the FIFO
(vsync) implementation being fundamentally broken leading to reduced
GPU-bound performance and 'barcoding' frametimes due to swapchain
starvation.
There are two protocols used to solve these two problems together --
fifo-v1 and commit-timing-v1, which implement the commit queue on the
compositor side, and a timestamp that frames are intended to be
displayed for/discarded respectfully.
To avoid severe performance regressions for developers targeting SDL3,
only pick Wayland as the default backend when these two protocols are
supported -- otherwise fallback to X11/XWayland.
We do this by having two VideoBootStraps, one which is tests the
preferred case, "wayland_preferred" (ie. if fifo-v1 + commit-timing-v1
are available init time), and the fallback, which is just "wayland",
the same name as before, which does no such tests.
Thus, forcing with SDL_VIDEO_DRIVER=wayland will go onto the fallback
option, and pick Wayland always, as usual, so there is no behaviour
change.
In the case that X11/XWayland is not available (ie. no DISPLAY), we will
still fallback to using Wayland without these protocols available.
Signed-off-by: Joshua Ashton <joshua@froggi.es>