Related #106229. The cursor-shape protocol allows us to not have to deal with cursor theming and instead depend on the
compositor for it.
This still does not quite solve the issue when the compositor doesn't implement the protocol
(or running under the x11 backend) but for gnome/kde and a few more this should resolve things.
Before, the WSI was unfortunately quite broken and we had work around it
by manually pacing frames. Needless to say it was not an ideal solution.
Now, the WSI can make use of the new fifo_v1 protocol to work properly.
If it's available, we'll trust the WSI by disabling manual frame pacing.
While we're at it, let's clean up the suspension code a bit by removing
some duplicated stuff and handling the suspension state through a switch
case.
I ported the new softclass macro too blindly. Apparently the various
window messages did not cast properly, skipping some important "deleted
window" checks.
The backend is now mature enough to not explode with multiple windows
but the `DisplayServer` API still cannot meet some guarantees required
by the various Wayland protocols we use. To meet those guarantees this
patch adds three new elements to the DisplayServer API, with relative
handling logic for `Window` and `Popup` nodes:
- `WINDOW_EVENT_FORCE_CLOSE`, which tells a window to *forcefully*
close itself and ensure a proper cleanup of its references, as Wayland
enforces this behavior;
- `WINDOW_FLAG_POPUP_WM_HINT`, which explicitly declares a window as a
"popup", as Wayland enforces this distinction and heuristics are not
reliable enough;
- `FEATURE_SELF_FITTING_WINDOWS`, which signals that the compositor can
fit windows to the screen automatically and that nodes should not do
that themselves.
Given the size of this feature, this patch also includes various
`WaylandThread` reworks and fixes including:
- Improvements to frame wait logic, with fixes to various stalls and a
configurable (through a `#define`) timeout amount;
- A proper implementation of `window_can_draw`;
- Complete overhaul of pointer and tablet handling. Now everything is
always accumulated and handled only on each respective `frame` event.
This makes their logic simpler and more robust.
- Better handling of pointer leaving and pointer enter/exit event
sending;
- Keyboard focus tracking;
- More solid window references using IDs instead of raw pointers as
windows can be deleted at any time;
- More aggressive messaging to window nodes to enforce rects imposed by
the compositor.
This fixes once and for all the core issue of different Godot `keycode`s
released from the same raw XKB keycode.
The `InputEventKey` `keycode` value _should_ map to the "unmodified"
key, but unfortunately there's an ambiguity with their encoding for
"special" keys ("delete", "insert", etc.), in witch they ignore their
unicode representation. This means that a key that is special when plain
but a character when modified would never be properly picked up, so we
do indeed change its keycode. As a consequence of this exception, some
Godot keys never receive release events and get "stuck".
This patch adds an extra check through an `HashMap` to "unstuck" keys
that changed while having the same keycode.
I also could not resist simplifying a bit the regular key event
generation method but this makes things more consistent and predictable
IMO.
We should only include the vendored headers for Wayland and libdecor-0 when
we use `so_wrap`, i.e. when we *don't* build against system libraries.
The libdecor-0 pkg-config file includes the `libdecor-0/` prefix already,
so its header should be included without it, and likewise in our so wrappers.
Fixes#102671.
The v1 version is deprecated and bound to be removed in the future from
all compositors. This patch adds a v1/v2 designator to everything
related to the protocol and prefers the v2 protocol if both are
available.
Additionally, renames the event handler to follow the Wayland interface
name, for consistency with the rest of the codebase.
Initially the WaylandThread cursor code was supposed to be as stateless
as possible but, as time went on, this wasn't possible.
This expectation made the resulting API quite convoluted, so this patch
aims to simplify it substantially bot in terms of API surface and, most
importantly, in terms of actual implementation complexity.
This patch also fixes custom cursors since I accidentally changed the
mmap flags to MAP_PRIVATE some time ago. This took me hours to notice.
This reduces even further the amount of work we have to do when scaling
and potentially improves input accuracy as now the input code is free
from any form of rounding.
Before of this patch, as explained in the usual
commented-wall-of-text-longer-than-the-actual-patch-itself™, due to the
multithreaded nature of the Wayland thread, it was possible to commit a
surface while the renderer was doing stuff, which was _very_ wrong.
Initially the consequences of such a sin weren't obvious but, now that
explicit synchronization is becoming more and more common, we can't
commit a buffer randomly without basically guaranteeing a nasty, nasty
crash (and we should have avoided commits altogether in the first place
to ensure atomic surface updates).
We now only trigger a commit _in the main thread_ when low processor usage
mode is on _and_ if we know that we won't be rendering anything as, due to
its intermittent nature, it makes "legacy" (pre xdg_wm_base v6) frame
callback based suspension quite annoying.
Previously we pretty much hardcoded most of the globals we requested,
causing compatibility issues with certain compositors like Weston, which
support only some pretty old versions or miss some more advanced
protocols.
To put fuel on the fire, we also errored out when certain protocols
weren't available, despite us being able to boot a game just fine (but
obviously with a degraded featureset).
The solution is to simply allow all the way from version 1 to the
current latest, adding some compatibility code (such as for older
`wl_output`s or newer `wl_pointer`s).
While we're at it, this commit also fixes a few typos and naming inconsistencies
I found.
This code was already partially there, although heavily incomplete and
nowadays commented out.
It got broken after the `WaylandThread` refactor and I didn't bother to
bring it over, preferring to `#if 0` it into oblivion for the time
being as I don't have a tablet/pen which support an eraser and tilt
reporting.
This commit brings it back and adds proper multi-tool support (needed
for eraser detection) thanks to winston-yallow, who could test this code
with their more capable tablet.
This is a pretty popular approach that took a while for me to wrap my
head around and which only recently got "official" support through an
update (xdg_shell version 6), so I think that this is all-in-all a
better option than the overkill 2000Hz ticking we have now :P
Basically, we wait for a frame event and, if either too much time passes
or we get the new `suspended` state, we consider the window as "hidden"
and stop drawing, ticking by the low usage rate.
This should work great for KDE and Mutter, which support the new state,
but not yet for sway, which is still stuck at a very old xdg_shell
version and thus falls back to the timeout approach.
Be aware that if we rely on timing out the engine will have to stall for
the whole timeout, which _could_ be problematic but doensn't seem like
it. Further testing is needed.
Special thanks go to the guys over at #wayland on OFTC, who very
patiently explained me this approach way too many times.
Not everything is yet implemented, either for Godot or personal
limitations (I don't have all hardware in the world). A brief list of
the most important issues follows:
- Single-window only: the `DisplayServer` API doesn't expose enough
information for properly creating XDG shell windows.
- Very dumb rendering loop: this is very complicated, just know that
the low consumption mode is forced to 2000 Hz and some clever hacks are
in place to overcome a specific Wayland limitation. This will be
improved to the extent possible both downstream and upstream.
- Features to implement yet: IME, touch input, native file dialog,
drawing tablet (commented out due to a refactor), screen recording.
- Mouse passthrough can't be implement through a poly API, we need a
rect-based one.
- The cursor doesn't yet support fractional scaling.
- Auto scale is rounded up when using fractional scaling as we don't
have a per-window scale query API (basically we need
`DisplayServer::window_get_scale`).
- Building with `x11=no wayland=yes opengl=yes openxr=yes` fails.
This also adds a new project property and editor setting for selecting the
default DisplayServer to start, to allow this backend to start first in
exported projects (X11 is still the default for now). The editor setting
always overrides the project setting.
Special thanks to Drew Devault, toger5, Sebastian Krzyszkowiak, Leandro
Benedet Garcia, Subhransu, Yury Zhuravlev and Mara Huldra.
