NVIDIA's Wayland EGL implementation sets explicit-sync acquire and
release points while presenting a frame. The requests emitted by
eglSwapBuffers and its final surface commit must be treated as one
logical transaction.
The pointer-warp path can commit the main surface from the input
thread while the render thread is inside eglSwapBuffers. If this
occurs between the explicit-sync requests, the cursor commit applies
incomplete pending state and the compositor disconnects the client
with:
explicit sync is used, but no release point is set
Add a surface lock and hold it across EGL presentation. Use the same
lock for direct commits, frame callback registration, and
pointer-constraint updates, replacing the narrower confinement lock.
This prevents another thread from splitting the EGL transaction and
removes the need for __NV_DISABLE_EXPLICIT_SYNC=1.
Serialize asynchronous image-description state and publish compositor
capabilities safely across the Wayland and render threads.
Use the predefined Windows-scRGB description, query each output image
description for its configured reference white, and reapply HDR when the
surface moves to an output with different colour settings.
There is no reason to call a bunch of stuff before the xdg_surface is
configured, so let's not call them and cause early painting to happen
should the compositor decide to send the `preferred_scale` message early.
This allows us to build with libdecor enabled as the selection to use it
is decided upon at runtime if the compositor `gnome-shell` is detected.
If the libdecor development headers are installed, by default it will
now be compiled in unless overridden by the user at compile time.
X11 needs to calibrate to get the best possible latency, as such it
needs the scene to render so that the render time of the scene can be
accounted for in the delay calculation.
Currently, we scale the desktop up to the next largest integer, and rely on
the wayland compositor to scale it back down to the correct size.
This is obviously undesirable.
In this commit, we attempt to detect the actual fractional scaling by finding
the current active mode in wl_output, and dividing it by the logical screen
size reported by xdg_output, taking into consideration screen rotation.
We then use wp_viewporter to set the exact buffer and viewport sizes if
fractional scaling is needed.
Instead of damaging the entire surface when rendering a cursor move,
we can use the EGL_KHR_swap_buffers_with_damage extension to only
damage the part of the window covered by the cursor. This should
reduce the cursor movement latency on Wayland.
The only addition to v4 was `wl_surface_damage_buffer`, which we do not
use.
This change should allow running on more compositors (even though v4 is
already old -- 5 years now).
Ref
3384f69ecf.
If the scale factor of an wl_output changes while the client is running,
the maximum scale factor is not updated. This may result in incorrect
scaling.
Therefore, when the scale factor is changed, we should generate a
resize event.
The Wayland display server is getting unwieldy due to the sheer size.
To make it easier to edit in the future, I split it into many components
based on logical boundaries.