Window
- The constructor made a fractional scale, a toplevel decoration and a
viewport from Device::fractionalScaleManager, Device::manager and
Device::wpViewporter without looking at them. Device::handle_global
binds those globals only when the compositor advertises them, and
Initialize requires only wl_shm, wl_compositor and xdg_wm_base, so on a
compositor without one of the three (GNOME's Mutter has no
xdg-decoration) the constructor handed libwayland a null proxy and
crashed before the window existed (#162). Each object is now made only
when its global is there, which Resize and the destructor already
assumed.
- The fractional scale needs the viewporter too: the preferred scale is
applied through the viewport, which shows the buffer's physical pixels at
width/scale x height/scale. A surface without a viewport is as large as
its buffer, so there the scale stays 1, which keeps pointer and touch
positions, configure sizes and the text-input caret, all converted by
it, in physical pixels; the compositor scales the window up on a HiDPI
output. A scale that changes after the constructor is still applied only
by the next resize, which is #165.
- Without xdg-decoration the window has no title bar, since the library
draws no client-side decorations.
Device
- The optional globals say they are optional, and that a request on a
null proxy crashes.
Tests
- WindowOptionalGlobals: hides xdg-decoration, wp_viewporter and
wp_fractional_scale_v1 from the Window one at a time and all at once,
by nulling the Device statics after Initialize, and renders, resizes
and closes a window each time without a protocol error. Before the fix
it crashed on the window without xdg-decoration. A global the compositor
does not offer is reported as a SKIP line, since the path that uses it
goes untested there.
README
- Which Wayland protocols the window needs, and what it does without the
optional ones.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Jorijn van der Graaf
670df31cc6