...when only one edge is anchored.
The layer-shell protocol specifies that a positive exclusive-zone value is
'meaningful' if the surface is anchored to either:
1. one edge
2. one edge and both perpendicular edges.
For example, if you wish to position a layer-shell client along the top
edge and make it exclusive, you should be able to either set anchor=TOP or
anchor=TOP|LEFT|RIGHT. It appears that many panels/bars use the latter
approach (anchor to an edge and also both perpendicular edges) which is
probably why this has not been reported previously.
This patch adds support for the first case and thereby makes exclusive
zone behaviour consistent with the protocol and also with sway's extant
layer-shell implementation.
Only the exclusion zone for mapped layer shell surfaces should be respected. In
particular, a layer shell surface that was mapped with an exclusion zone but is
now unmapped should not adjust the usable area.
Closes: https://gitlab.freedesktop.org/wlroots/wlroots/-/issues/3471
...in wlr_scene_layer_surface_v1_configure()
Reproduce bug with waybar by setting `"margin": 5,`
in ~/.config/waybar/config. It will result in the right edge of the panel
extending outside the edge of the output.
The bug can also be reproduced with gtk-layer-demo by anchoring
left/right/top/bottom and setting respective margins
Relates-to: https://github.com/labwc/labwc/issues/382
Kirill Primak
Johan Malm
Kenny Levinsen
Alexander Orzechowski