OpenGL apparently needs to not do any drawing between wl_egl_window_resize
and eglSwapBuffers, but Vulkan apps don't use SDL to present, so they
never call into an equivalent of SDL_GL_SwapWindow where our Wayland code
was handling pending resize work.
Fixes Bugzilla #4722.
For starters, we need to correctly respond to 0,0 configure after unsetting
fullscreen. Also, turns out that there should be no drawing calls at all
in between eglSwapBuffers and wl_egl_window_resize, as otherwise EGL can
already allocate a wrongly sized buffer for a next frame, so handle those
together.
This is just in parity with the existing zxdg-shell-unstable-v6 code. Making
the Wayland target robust (and uh, with title bars) is going to take a lot
of work on top of this.
This is meant to be the desktop-enhanced version of wl_shell. Right now we
just match what the existing wl_shell code does, but there are other areas of
functionality available to us now, that we can fill in later.
This uses the "unstable" API, since this is what ships in Ubuntu 17.10 (as
part of Wayland 1.10), but Wayland 1.12 promotes this to stable with extremely
minor changes. We will add support for the stable version when it makes sense
to do so.
x414e54
Wayland will sometimes send empty resize events (0 width and 0 height) to the client. I have not worked out the exact conditions a client would receive these but I can assume it might be if the window is offscreen or not mapped yet.
This causes issues with some SDL clients as they receive the 0x0 event and unexpected resize event or might not request to resize back to the correct size.
As per the wl_shell Wayland spec configure events are only a suggestion and the client is free to ignore or pick a different size (this is how min/max and fixed aspect ratio is supped to be implemented).
A patch is attached but is just the first iteration and I will fix any issues such as checking for FULLSCREEN/MAXIMIZED or RESIZABLE flags unless someone else fixes this first.
I have update to take into account non resizable and fullscreen windows. Also adding in maximize/restore and title functions for Wayland.
Generate the C protocol files from the protocol XML files installed by
wayland-protocols, and use them to implement support for relative pointer
motions and pointer locking.
Note that at the time, the protocol is unstable and may change in the future.
Any future breaking changes will, however, fail gracefully and result in no
regressions compared to before this patch.
The internal function SDL_EGL_LoadLibrary() did not delete and remove a mostly
uninitialized data structure if loading the library first failed. A later try to
use EGL then skipped initialization and assumed it was previously successful
because the data structure now already existed. This led to at least one crash
in the internal function SDL_EGL_ChooseConfig() because a NULL pointer was
dereferenced to make a call to eglBindAPI().
