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.
The set_position method computes the anchors/offsets to match a
rectangle at the given position with size "size_cache". However, when
the Control's combined minimum size is larger than the size obtained
through the offsets and anchors, "size_cache" is set to be as large as
the combined minimum size. Therefore, when position is set while the
combined minimum size is larger than the rectangle given by the anchors
and offsets, it would resize these two fields, which would then stop
the Control from shrinking when its combined minimum size decreased. To
fix this, set_position now uses the size given by the offsets and
anchors instead of the "size_cache" field. This way, the rectangle
denoted by the offsets and anchors is simply moved, without being
resized, enabling the Control to shrink automatically when its combined
minimum size decreases. I also added a test case to ensure that the
Control shrinks correctly after setting its position while it has a
larger custom minimum size than the one obtained through the offsets
and anchors.
This introduces two new booleans approx_pos_changed and approx_size_changed which are the pos_changed and size_changed booleans that are immune to floating point errors.
This aims to fix two bugs in one shot. #93832 and #48935
