Add blurring on MacOS, Windows and Linux (setup dependent)

Cargo.toml

@@ -213,7 +213,8 @@ web-sys = "0.3.69"
 web-time = "1.1"
 wgpu = "24.0"
 window_clipboard = "0.4.1"
-winit = { git = "https://github.com/iced-rs/winit.git", rev = "11414b6aa45699f038114e61b4ddf5102b2d3b4b" }
+# TODO: switch back to iced-rs/winit if merged
+winit = { git = "https://github.com/pml68/winit.git", rev = "30deb1b4641b9ec0d4568bd8b521c7419d3a172a" }
 
 [workspace.lints.rust]
 rust_2018_idioms = { level = "deny", priority = -1 }

core/src/window/settings.rs

@@ -62,6 +62,21 @@ pub struct Settings {
     /// Whether the window should be transparent.
     pub transparent: bool,
 
+    /// Whether the window should have a blurred background.
+    ///
+    /// Note that the blurry effect is only applied to transparent windows. You need to enable
+    /// [`Settings::transparent`] and set a proper opacity value to the background color with
+    /// `Application::style`.
+    ///
+    /// On Windows, it sets the [backdrop][winit_backdrop] to `TransientWindow`, making the window [acrylic][acrylic].
+    ///
+    /// On MacOS and Linux, it uses `set_blur`. For more details, please refer to the [winit documentation][winit_set_blur].
+    ///
+    /// [winit_backdrop]: https://docs.rs/winit/latest/winit/platform/windows/enum.BackdropType.html
+    /// [winit_set_blur]: https://docs.rs/winit/latest/winit/window/struct.Window.html#method.set_blur
+    /// [acrylic]: https://learn.microsoft.com/en-us/windows/apps/design/style/acrylic
+    pub blur: bool,
+
     /// The window [`Level`].
     pub level: Level,
 
@@ -95,6 +110,7 @@ impl Default for Settings {
             resizable: true,
             decorations: true,
             transparent: false,
+            blur: false,
             level: Level::default(),
             icon: None,
             exit_on_close_request: true,

core/src/window/settings/macos.rs

@@ -1,12 +1,25 @@
 //! Platform specific settings for macOS.
 
 /// The platform specific window settings of an application.
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub struct PlatformSpecific {
     /// Hides the window title.
     pub title_hidden: bool,
     /// Makes the titlebar transparent and allows the content to appear behind it.
     pub titlebar_transparent: bool,
     /// Makes the window content appear behind the titlebar.
     pub fullsize_content_view: bool,
+    /// Sets the window's blur radius.
+    pub blur_radius: i64,
+}
+
+impl Default for PlatformSpecific {
+    fn default() -> Self {
+        Self {
+            title_hidden: false,
+            titlebar_transparent: false,
+            fullsize_content_view: false,
+            blur_radius: 80,
+        }
+    }
 }

src/application.rs

@@ -309,6 +309,17 @@ impl<P: Program> Application<P> {
         }
     }
 
+    /// Sets the [`window::Settings::blur`] of the [`Application`].
+    pub fn blur(self, blur: bool) -> Self {
+        Self {
+            window: window::Settings {
+                blur,
+                ..self.window
+            },
+            ..self
+        }
+    }
+
     /// Sets the [`window::Settings::level`] of the [`Application`].
     pub fn level(self, level: window::Level) -> Self {
         Self {

winit/src/conversion.rs

@@ -40,6 +40,7 @@
         .with_decorations(settings.decorations)
         .with_transparent(settings.transparent)
         .with_window_icon(settings.icon.and_then(icon))
+        .with_blur(settings.blur)
         .with_window_level(window_level(settings.level))
         .with_visible(settings.visible);
 
@@ -79,6 +80,7 @@
 
     #[cfg(target_os = "windows")]
     {
+        use winit::platform::windows::BackdropType;
         use winit::platform::windows::WindowAttributesExtWindows;
 
         attributes = attributes
@@ -90,6 +92,11 @@
         attributes = attributes.with_undecorated_shadow(
             settings.platform_specific.undecorated_shadow,
         );
+
+        if settings.blur {
+            attributes =
+                attributes.with_system_backdrop(BackdropType::TransientWindow)
+        }
     }
 
     #[cfg(target_os = "macos")]
@@ -103,7 +110,8 @@
             )
             .with_fullsize_content_view(
                 settings.platform_specific.fullsize_content_view,
-            );
+            )
+            .with_blur_radius(settings.platform_specific.blur_radius);
     }
 
     #[cfg(target_os = "linux")]
@@ -289,7 +297,7 @@
             Ime::Enabled => input_method::Event::Opened,
             Ime::Preedit(content, size) => input_method::Event::Preedit(
                 content,
                 size.map(|(start, end)| (start..end)),
             ),
             Ime::Commit(content) => input_method::Event::Commit(content),
             Ime::Disabled => input_method::Event::Closed,