Wait up to 100 milliseconds, since the window manager might alter or
outright veto the window change...or not respond at all.
In a well-functioning system, though, this should help make sure
that SDL_SetWindowPosition's results match reality.
Fixes Bugzilla #4646.
Martin Fiedler
To be precise, this is about *desktop OpenGL* on X11. For OpenGL ES, EGL is already used (as it's the only way to get an OpenGL ES context), as Sylvain noted above.
To shine some light on why this is needed:
In 99% of all cases, using GLX on X11 is fine, even though it's effectively deprecated in favor of EGL [1]. However, there's at least one use case that *requires* the OpenGL context being created with EGL instead of GLX, and that's DRM_PRIME interoperability: The function glEGLImageTargetTexture2DOES simply doesn't work with GLX. (Currently, Mesa actually crashes when trying that.)
Some example code:
https://gist.github.com/kajott/d1b29c613be30893c855621edd1f212e
Runs on Intel and open-source AMD drivers just fine (others unconfirmed), but with #define USE_EGL 0 (i.e. forcing it to GLX), it crashes. The same happens when using SDL for window and context creation.
The good news is that most of the pieces for EGL support on X11 are already in place: SDL_egl.c is pretty complete (and used for desktop OpenGL on Wayland, for example), and SDL_x11opengl.c has the aforementioned OpenGL-ES-on-EGL support. However, when it comes to desktop OpenGL, it's hardcoded to fall back to GLX.
I'm not advocating to make EGL the default for desktop OpenGL on X11; don't fix what ain't broken. But something like an SDL_HINT_VIDEO_X11_FORCE_EGL would be very appreciated to make use cases like the above work with SDL.
[1] source: Eric Anholt, major Linux graphics stack developer, 7 years ago already - see last paragraph of https://www.phoronix.com/scan.php?page=news_item&px=MTE3MTI
Use XGetKeyboardControl to initialize the current XKeyboardState, and
skip XAutoRepeatOn invocation if global_auto_repeat is AutoRepeatModeOn.
This fixes SDL2 when the X11 client is untrusted.
Do not try to guess MIT_SHM extension availability from the string
returned by XDisplayName, use the appropriate API instead.
This fixes SDL2 inside hasher.
SDL_SendWindowEvent will only send a RESTORED event if the window has
the minimized or maximized flag set. However, for a SHOWN event, it
will clear the minimized flag. Since the SHOWN event was being sent
first for a MapNotify event, the RESTORED event would never be sent.
Swapping the SendWindowEvent calls around fixes this.
https://bugzilla.libsdl.org/show_bug.cgi?id=4821
Solra Bizna
I have written a program that, in the event that the user requests more MSAA samples than their hardware supports, attempts to gracefully fall back to the best MSAA available. This code works with my conventional OpenGL renderer, but if I change nothing about the code except to make it request an OpenGL ES profile instead, Xlib kills the program with an error that looks like:
X Error of failed request: BadWindow (invalid Window parameter)
Major opcode of failed request: 4 (X_DestroyWindow)
Resource id in failed request: 0x5c00008
Serial number of failed request: 188
Current serial number in output stream: 193
To trigger the bug, attempt to create a window with the SDL_WINDOW_OPENGL flag, with SDL_GL_CONTEXT_PROFILE_MASK set to SDL_GL_CONTEXT_PROFILE_ES, and with SDL_GL_MULTISAMPLESAMPLES set to any unsupported value. SDL_CreateWindow properly returns NULL, but at this point the program is already doomed. Xlib will shortly terminate the program with an error. Calling SDL_CreateWindow again will immediately trigger this termination.
I have attached a skeletal program that reproduces this bug for me. Replacing SDL_GL_CONTEXT_PROFILE_ES with SDL_GL_CONTEXT_PROFILE_COMPATIBILITY avoids the bug (but, obviously, doesn't create an OpenGL ES context).
As I suspected, the problem was with XDestroyWindow being called twice on the same window. The X11_CreateWindow function in src/video/x11/SDL_x11window.c calls SetupWindowData. If initialization fails after that point, XDestroyWindow gets called on the window by a subsequent call to X11_DestroyWindow. But, later in the same function, iff a GLES context is requested and initializing it fails, X11_XDestroyWindow (which wraps XDestroyWindow) is manually called. Shortly after, the intended call to X11_DestroyWindow occurs, which attempts to destroy the same window again. Boom.
(The above confusing summary involves three separate, similarly-named functions: XDestroyWindow, X11_DestroyWindow, X11_XDestroyWindow)
I have attached a simple patch that removes the redundant X11_XDestroyWindow calls. I've tested that XDestroyWindow still gets called for the windows in question, and that it only gets called once.
This can happen if a window is still grabbed when we try to move it, or if
the X11 ecosystem is just in a bad mood, I guess.
This makes sure that SDL will report the correct position for a window;
otherwise, SDL_GetWindowPosition will just report whatever the last
SDL_SetWindowPosition call requested, even if the window didn't actually move.
Fixes Bugzilla #4646.
With multitouch, register to receive XI_Motion (which desctivates MotionNotify),
so that we can distinguish real mouse motions from synthetic one.
(bug 4690)
Andrei Drexler
For X11 GenericEvents, the associated data is only available between a call to XGetEventData and the matching XFreeEventData, i.e. in X11_HandleGenericEvent. Trying to call XGetEventData a second time on the same event will fail, so an application that wants to inspect XInput2 events (e.g. for stylus pressure) has no way of retrieving its data from queued SYSWM events.
The attached patch (based on SDL-2.0.7-11629) sends SYSWM messages from X11_HandleGenericEvent while the data is still available, allowing client code to register an event filter/watcher and process the event inside the callback.
Touch device types include SDL_TOUCH_DEVICE_DIRECT (a touch screen with window-relative coordinates for touches), SDL_TOUCH_DEVICE_INDIRECT_ABSOLUTE (a trackpad-style device with absolute device coordinates), and SDL_TOUCH_DEVICE_INDIRECT_RELATIVE (a trackpad-style device with screen cursor-relative coordinates).
Phone screens are an example of a direct device type. Mac trackpads are the indirect-absolute touch device type. The Apple TV remote is an indirect-relative touch device type.
Include guards in most changed files were missing, I added them keeping
the same style as other SDL files. In some cases I moved the include
guards around to be the first thing the header has to take advantage of
any possible improvements compiler may have for inclusion guards.
It needs to use Bool (which is an int) and not BOOL (which is CARD8), which
causes problems on platforms with different byte order and alignment, etc.
Fixes Bugzilla #4326.
First: disable d'n'd events by default; most apps don't need these at all, and
if an app doesn't explicitly handle these, each drop on the window will cause
a memory leak if the events are enabled. This follows the guidelines we have
for SDL_TEXTINPUT events already.
Second: when events are enabled or disabled, signal the video layer, as it
might be able to inform the OS, causing UI changes or optimizations (for
example, dropping a file icon on a Cocoa app that isn't accepting drops will
cause macOS to show a rejection animation instead of the drop operation just
vanishing into the ether, X11 might show a different cursor when dragging
onto an accepting window, etc).
Third: fill in the drop event details in the test library and enable the
events in testwm.c for making sure this all works as expected.
"Applications (such as SDL's testgesture) do "event.tfinger.x * window_width"
to find window coord. Currently the X11 XInput2 backend expects application
to do "event.tfinger.x * (window_width-1)" instead.
X11 XInput2 touch events are normalized so x is 1.0 at "width - 1" but other
SDL backends appear to have x be 1.0 at "width". Same issue for touch event
y with regards to height."
Fixes Bugzilla #4183.
Callum McGing
This patch allows the user to disable the behaviour that blocks the compositor through a new hint: SDL_VIDEO_X11_NET_WM_BYPASS_COMPOSITOR. This allows tools or other windowed applications to behave properly under KWin.
SDL now builds with gcc 7.2 with the following command line options:
-Wall -pedantic-errors -Wno-deprecated-declarations -Wno-overlength-strings --std=c99
tomwardio
Remove static int vm_error and vm_event, use local variables instead.
This fixes unused variable errors when compiling with SDL_VIDEO_DRIVER_X11_XINERAMA undefined.
src/video/x11/SDL_x11modes.c:505:22: error: unused variable 'vm_error' [-Werror,-Wunused-variable]
src/video/x11/SDL_x11modes.c:505:12: error: unused variable 'vm_event' [-Werror,-Wunused-variable]
Trent Gamblin
The documentation for SDL_TouchFingerEvent says that the x and y coordinates are normalised between 0-1. I've found that to be true on Windows, Android and iOS but on X11 they are in pixel coordinates. This patch fixes the issue. This was the cleanest way I could do it with what was available without changing things around a lot but you may know a better way.
Mart?n Golini
I'm having a very slow initialization of the video subsystem that locks the window creation for about 500 ms ( tested in at least 4 different systems ). What i found is that X11_InitModes_XRandR is using XRRGetScreenResources, that explicitly ask to poll the hardware for changes. This is not really necessary since if the data is already available you can use XRRGetScreenResourcesCurrent.
I attached a tentative patch that fix this issue. With the patch there's no lock when the subsystem is initialized and the window creation is instant in my applications. The patch only uses XRRGetScreenResourcesCurrent in X11_InitModes_XRandR but it could be potentially used in X11_GetDisplayModes and X11_SetDisplayMode.
This is necessary because we need to see if GLES compat extensions exist.
All of this code (including ShouldUseTextureFramebuffer()) should be
revisited after 2.0.6 ships; ideally we don't make throwaway contexts if
we can avoid it...but maybe we can't. I hear Vulkan is pretty cool.
Fixes Bugzilla #3725.