Eliminate excessive calls to SetFullscreen by removing the calls in the libdecor and xdg-toplevel config callbacks.
These calls were being made there in case something explicitly called the window minimization function from within SDL, which unsets fullscreen, and as minimizing a window in Wayland is just a suggestion to the compositor and doesn't actually change the window state or communicate anything back to the application, it was necessary to call SetFullscreen in every call to the config functions just in case something minimized a window via SDL_MinimizeWindow() and later needed to restore it. GNOME in particular had issues when fullscreen set/unset operations were being hammered, leading to overlapping acks and commits when switching to fullscreen.
With the new video system flag to disable unsetting fullscreen when minimizing a window, these calls in the configuration functions are no longer needed and can be removed. This significantly reduces calls to the SetFullscreen() function, reverts #6044 while fixing the issue, and fixes a similar problem when hiding and showing a window initially created with fullscreen flags.
Don't call the roundtrip in ShowWindow unless restoring a previously hidden window. This fixes a regression in GNOME when creating a window with the fullscreen flag set, as the fullscreen window will be positioned down the screen by the height of the top bar if the window is made fullscreen on the primary display and the roundtrip is called when initially displaying the window.
Previously, the surface damage region was being set in the same callback used for preventing render hangs in the GL backend when the surface was not visible. This was not ideal, as the callback was never fired in the case of using a different render backend or having a swap interval of 0. Use a separate frame callback for setting the surface damage region to ensure that it fires reliably, regardless of the backend being used or swap interval.
Compartmentalize the fullscreen mode emulation code blocks, unify the windowed/fullscreen viewport logic, consolidate all window geometry code into a central function to eliminate blocks of duplicate code and rename related variables and functions to more explicitly reflect their purpose.
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.
When using emulated display modes, the output size is often larger than the drawable buffer. As the surface damage region is automatically calculated from the smaller drawable buffer size, the damage region needs to be manually set to cover the entire viewport region or visual repaint artifacts can result.
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.
If we get a SDL_SetWindowSize() call right after SDL_SetWindowFullscreen() but
before we've gotten a new configure event from the compositor, the attempt to
set our window size will silently fail (when libdecor is enabled).
Fix this by remembering that we need to commit a new size, so we can do that
in decoration_frame_configure().
Dispatching all events in Wayland_GLES_SwapWindow leads to resizes being
acked before the program has a chance to handle the resize. This change
reduces jumping on fullscreen transition with apps that call
SDL_PollEvent before issuing any render calls.
Commit 871c11191bfc7214061a3da37c112522a102ddf5 removed delayed
resize handling, but it left the whole structure untouched that
now became unnecessary. To help with code clarity, get rid
of the structure where pending resize state used to be stored
and pass all the data directly to Wayland_HandlePendingResize
(now renamed to Wayland_HandleResize, since it's not "pending"
anymore but applied immediately)
Some Wayland compositors send (0,0) as "suggested" configure event sizes to
indicate that the client has to decide on its own which sizes to used. This
is commonly done when restoring from maximised, fullscreen or tiles states
to fullscreen.
We now store the last known floating states in a new set of variables and
restore them when we receive such a (0,0) configure event.
If you hide a window on Mutter, for example, the compositor never requests
new frames, which will cause Mesa to block forever in eglSwapBuffers to
satisfy the swap interval.
We now always set the swap interval to 0 and manage this ourselves, handing
the frame to Wayland when it requests a new one, and timing out at 10fps just
to keep apps moving if the compositor wants no frames at all.
My understanding is that other protocols are coming that might improve upon
this solution, but for now it solves the total hang.
Fixes#4335.
KWin has supported the shared and formalised zxdg_decoration since
Plasma 5.16 which came out mid 2019.
Whilst it made sense to support them both for a while, it should not be
needed for future SDL releases.
This gives us flexibility to add others hints to control keyboard grab behavior
without having to touch all of the backends. It also allows us to possibly
expose keyboard grab separately from mouse grab for applications that want to
manage those independently.
We support both the org.freedesktop.ScreenSaver D-Bus API (same as the X11
backend) and the Wayland idle_inhibit_unstable_v1 protocol.
Some Wayland compositors only support one or the other, so we need both to
for broad compatibility.
Use zwp_keyboard_shortcuts_inhibit_manager_v1 to allow SDL applications
to capture system keyboard shortcuts like Alt+Tab when keyboard grab is
enabled via SDL_HINT_GRAB_KEYBOARD.
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.
