diff --git a/doc/classes/DisplayServer.xml b/doc/classes/DisplayServer.xml
index a05404826673..688e1b70cae9 100644
--- a/doc/classes/DisplayServer.xml
+++ b/doc/classes/DisplayServer.xml
@@ -1103,8 +1103,9 @@
Returns the scale factor of the specified screen by index.
- [b]Note:[/b] On macOS returned value is [code]2.0[/code] for hiDPI (Retina) screen, and [code]1.0[/code] for all other cases.
- [b]Note:[/b] This method is implemented only on macOS.
+ [b]Note:[/b] On macOS, the returned value is [code]2.0[/code] for hiDPI (Retina) screens, and [code]1.0[/code] for all other cases.
+ [b]Note:[/b] On Linux (Wayland), the returned value is accurate only when [param screen] is [constant SCREEN_OF_MAIN_WINDOW]. Due to API limitations, passing a direct index will return a rounded-up integer, if the screen has a fractional scale (e.g. [code]1.25[/code] would get rounded up to [code]2.0[/code]).
+ [b]Note:[/b] This method is implemented only on macOS and Linux (Wayland).
diff --git a/editor/editor_settings.cpp b/editor/editor_settings.cpp
index cec50ac30f0a..bd68fa5de58e 100644
--- a/editor/editor_settings.cpp
+++ b/editor/editor_settings.cpp
@@ -1540,6 +1540,19 @@ String EditorSettings::get_editor_layouts_config() const {
float EditorSettings::get_auto_display_scale() const {
#ifdef LINUXBSD_ENABLED
if (DisplayServer::get_singleton()->get_name() == "Wayland") {
+ float main_window_scale = DisplayServer::get_singleton()->screen_get_scale(DisplayServer::SCREEN_OF_MAIN_WINDOW);
+
+ if (DisplayServer::get_singleton()->get_screen_count() == 1 || Math::fract(main_window_scale) != 0) {
+ // If we have a single screen or the screen of the window is fractional, all
+ // bets are off. At this point, let's just return the current's window scale,
+ // which is special-cased to the scale of `SCREEN_OF_MAIN_WINDOW`.
+ return main_window_scale;
+ }
+
+ // If the above branch didn't fire, fractional scaling isn't going to work
+ // properly anyways (we're need the ability to change the UI scale at runtime).
+ // At this point it's more convenient to "supersample" like we do with other
+ // platforms, hoping that the user is only using integer-scaled screens.
return DisplayServer::get_singleton()->screen_get_max_scale();
}
#endif
diff --git a/platform/linuxbsd/wayland/display_server_wayland.cpp b/platform/linuxbsd/wayland/display_server_wayland.cpp
index 1c3cae0435ef..f7995472d087 100644
--- a/platform/linuxbsd/wayland/display_server_wayland.cpp
+++ b/platform/linuxbsd/wayland/display_server_wayland.cpp
@@ -550,7 +550,15 @@ float DisplayServerWayland::screen_get_scale(int p_screen) const {
MutexLock mutex_lock(wayland_thread.mutex);
if (p_screen == SCREEN_OF_MAIN_WINDOW) {
- p_screen = window_get_current_screen();
+ // Wayland does not expose fractional scale factors at the screen-level, but
+ // some code relies on it. Since this special screen is the default and a lot
+ // of code relies on it, we'll return the window's scale, which is what we
+ // really care about. After all, we have very little use of the actual screen
+ // enumeration APIs and we're (for now) in single-window mode anyways.
+ struct wl_surface *wl_surface = wayland_thread.window_get_wl_surface(MAIN_WINDOW_ID);
+ WaylandThread::WindowState *ws = wayland_thread.wl_surface_get_window_state(wl_surface);
+
+ return wayland_thread.window_state_get_scale_factor(ws);
}
return wayland_thread.screen_get_data(p_screen).scale;