Fix scale-monitor-framebuffer inconsistencies (#534)

* Fix scale-monitor-framebuffer inconsistencies

src/components/applications.js

@@ -1,11 +1,14 @@
 import Shell from 'gi://Shell';
 import Clutter from 'gi://Clutter';
 import Meta from 'gi://Meta';
+import Gio from 'gi://Gio'
 import * as Main from 'resource:///org/gnome/shell/ui/main.js';
 
 import { PaintSignals } from '../effects/paint_signals.js';
 import { ApplicationsService } from '../dbus/services.js';
 
+const mutter_gsettings = new Gio.Settings({ schema: 'org.gnome.mutter' });
+
 
 export const ApplicationsBlur = class ApplicationsBlur {
     constructor(connections, settings, _) {
@@ -416,15 +419,27 @@ export const ApplicationsBlur = class ApplicationsBlur {
         });
     }
 
+    /// Compute the size and position for a blur actor.
+    /// If `scale-monitor-framebuffer` experimental feature if on, we don't need to manage scaling.
+    /// Else, on wayland, we need to divide by the scale to get the correct result.
     compute_allocation(meta_window) {
+        const scale_monitor_framebuffer = mutter_gsettings.get_strv('experimental-features')
+            .includes('scale-monitor-framebuffer');
+        const is_wayland = Meta.is_wayland_compositor();
+        const monitor_index = meta_window.get_monitor();
+        // check if the window is using wayland, or xwayland/xorg for rendering
+        const scale = !scale_monitor_framebuffer && is_wayland && meta_window.get_client_type() == 0
+            ? Main.layoutManager.monitors[monitor_index].geometry_scale
+            : 1;
+
         let frame = meta_window.get_frame_rect();
         let buffer = meta_window.get_buffer_rect();
 
         return {
-            x: (frame.x - buffer.x),
-            y: (frame.y - buffer.y),
-            width: frame.width,
-            height: frame.height
+            x: (frame.x - buffer.x) / scale,
+            y: (frame.y - buffer.y) / scale,
+            width: frame.width / scale,
+            height: frame.height / scale
         };
     }
 
@@ -532,4 +547,4 @@ export const ApplicationsBlur = class ApplicationsBlur {
         if (this.settings.DEBUG)
             console.log(`[Blur my Shell > applications] ${str}`);
     }
-};
+};