wayland/output: Report unscaled size even in logical layout mode
In physical layout mode, the size and scale of the wl_output matches
the actual monitor:
| Monitor | wl_output |
GdkMonitor |
|---|---|---|
| 3840×2160 @1 | 3840×2160 @1 | 3840×2160 @1 |
| 3840×2160 @2 | 3840×2160 @2 | 1920×1080 @2 |
GTK currently does not support xdg_output. To estimate the logical
output size for GdkMonitor, it divides the output's size by its scale
factor. There might be other legacy clients making the same assumption.
In logical layout mode, mutter currently reports logical geometry for
the wl_outputs, but this no longer matches the monitors:
| Monitor | wl_output |
GdkMonitor |
|---|---|---|
| 3840×2160 @1 | 3840×2160 @1 | 3840×2160 @1 |
| 3840×2160 @2 | 1920×1080 @2 | 960×540 @2 |
| 3840×2160 @1.5 | 2560×1440 @2 | 1280×720 @2 |
This patch changes logical layout mode to multiply the sizes by the
wl_output's scale factor before sending them to the client. Now the
sizes match the physical layout mode again:
| Monitor | wl_output |
GdkMonitor |
|---|---|---|
| 3840×2160 @1 | 3840×2160 @1 | 3840×2160 @1 |
| 3840×2160 @2 | 3840×2160 @2 | 1920×1080 @2 |
| 3840×2160 @1.5 | 5120×2880 @2 | 2560×1440 @2 |
Unfortunately, non-integer output scales are not representable in
wl_output. Still, I believe these values are better than before, and
the best we can do for clients that do not know about xdg_output: The
size of the output will match the size that a buffer for a fullscreen
surface should have at the indicated scale.
Fixes part of https://bugzilla.mozilla.org/show_bug.cgi?id=1534089