fix(picker): Windows without transparency shows an opaque sheet, without the black box or the bear

.github/oversized.txt

@@ -1,2 +1,2 @@
 1893 app/src-tauri/src/lib.rs
-1965 crates/linkunbound-shell/src/main.rs
+1952 crates/linkunbound-shell/src/main.rs

crates/linkunbound-shell/src/look.rs

@@ -5,24 +5,37 @@
 use slint::ComponentHandle;
 
 pub fn style(picker: &Picker, chosen: PickerStyle) {
-    let look = match chosen {
+    picker.set_look(match chosen {
         PickerStyle::Classic => Look::List,
         PickerStyle::Sheet => Look::Tiles,
         PickerStyle::Compact => Look::Compact,
         PickerStyle::Bear => Look::Bear,
-    };
-    let clear = native_glass();
-    picker.set_look(look);
+    });
+    settle(picker);
+}
+
+/// A remote session or energy saver can start between two links.
+pub fn settle(picker: &Picker) {
+    dress_for(picker, !blends());
+}
+
+/// Unblended, the shadow and the bear would come out as black boxes.
+fn dress_for(picker: &Picker, solid: bool) {
+    let look = picker.get_look();
+    let clear = !solid && native_glass();
     let palette = picker.global::<Palette>();
+    palette.set_solid(solid);
     palette.set_clear(clear);
     palette.set_tint(tint());
     palette.set_glass_corner(if cfg!(target_os = "macos") {
         corner_of(picker) as f32
+    } else if solid && !dwm_rounds() {
+        0.0
     } else {
         DWM_CORNER
     });
-    palette.set_see_through(see_through());
-    picker.set_halo(if look == Look::List || clear {
+    palette.set_see_through(!solid && see_through());
+    picker.set_halo(if look == Look::List || clear || solid {
         0.0
     } else {
         HALO
@@ -59,6 +72,10 @@
 /// painted sheet and its shadow come back. Returns whether the window changed size.
 pub fn wear_backdrop(picker: &Picker, handle: isize) -> bool {
     let palette = picker.global::<Palette>();
+    if palette.get_solid() {
+        wear_solid(handle, !palette.get_light());
+        return false;
+    }
     if !palette.get_clear() {
         take_off_glass(handle);
         return false;
@@ -74,6 +91,18 @@
     true
 }
 
+pub fn dress_the_window(picker: &Picker) {
+    let Some(handle) = crate::native_handle(picker.window()) else {
+        return;
+    };
+    crate::host::keep_off_the_taskbar(handle, corner_of(picker));
+    if wear_backdrop(picker, handle) {
+        beside_the_pointer(picker);
+    }
+    follow(picker);
+    crate::host::take_the_keyboard(handle);
+}
+
 /// The picker belongs to the click that summoned it, not to the middle of a screen.
 pub fn beside_the_pointer(picker: &Picker) {
     let Some(pointer) = crate::host::cursor() else {
@@ -156,6 +185,37 @@
     }
 }
 
+#[cfg(windows)]
+fn blends() -> bool {
+    linkunbound_win::transparency_is_on() && linkunbound_win::blends_windows()
+}
+
+/// macOS blends every window; only the material can go.
+#[cfg(not(windows))]
+fn blends() -> bool {
+    true
+}
+
+#[cfg(windows)]
+fn dwm_rounds() -> bool {
+    linkunbound_win::dwm_rounds_corners()
+}
+
+#[cfg(not(windows))]
+fn dwm_rounds() -> bool {
+    false
+}
+
+#[cfg(windows)]
+fn wear_solid(window: isize, dark: bool) {
+    if dwm_rounds() {
+        linkunbound_win::wear_solid(window, dark);
+    }
+}
+
+#[cfg(not(windows))]
+fn wear_solid(_window: isize, _dark: bool) {}
+
 #[cfg(windows)]
 fn see_through() -> bool {
     linkunbound_win::transparency_is_on()
@@ -216,7 +276,7 @@
 
 #[cfg(test)]
 mod tests {
-    use super::{corner_of, native_glass, place_near, style, wear_backdrop};
+    use super::{corner_of, dress_for, native_glass, place_near, style, wear_backdrop};
     use linkunbound_core::PickerStyle;
     use linkunbound_shell::{CLASSIC_CORNER, CORNER, HALO, Palette, Picker};
     use slint::ComponentHandle;
@@ -234,11 +294,15 @@
         let clear = native_glass();
 
         style(&picker, PickerStyle::Sheet);
+
+        dress_for(&picker, false);
         assert_eq!(picker.global::<Palette>().get_clear(), clear);
         assert_eq!(picker.get_halo(), if clear { 0.0 } else { HALO });
         assert!((corner_of(&picker) - CORNER).abs() < f64::EPSILON);
 
         style(&picker, PickerStyle::Classic);
+
+        dress_for(&picker, false);
         assert_eq!(picker.get_halo(), 0.0);
         assert!((corner_of(&picker) - CLASSIC_CORNER).abs() < f64::EPSILON);
     }
@@ -252,9 +316,13 @@
         let near_the_top = (900, 2);
 
         style(&picker, PickerStyle::Classic);
+
+        dress_for(&picker, false);
         let (_, list_y) = place_near(&picker, near_the_top, screen);
 
         style(&picker, PickerStyle::Bear);
+
+        dress_for(&picker, false);
         picker.set_halo(0.0);
         let (_, bear_y) = place_near(&picker, near_the_top, screen);
         let rise = crate::mascot::rise(&picker);
@@ -273,13 +341,17 @@
         let palette = picker.global::<Palette>();
 
         style(&picker, PickerStyle::Sheet);
+
+        dress_for(&picker, false);
         palette.set_clear(true);
         picker.set_halo(0.0);
         assert!(wear_backdrop(&picker, 0), "the tiles grow by their shadow");
         assert!(!palette.get_clear());
         assert_eq!(picker.get_halo(), HALO);
 
         style(&picker, PickerStyle::Classic);
+
+        dress_for(&picker, false);
         palette.set_clear(true);
         assert!(!wear_backdrop(&picker, 0), "the list has no shadow to add");
         assert!(!palette.get_clear());
@@ -289,4 +361,39 @@
             "a painted sheet asks for nothing"
         );
     }
+
+    /// Unblended, every look fills its window with no shadow, material or bear.
+    #[test]
+    fn a_system_that_blends_nothing_gets_an_opaque_sheet() {
+        let picker = picker();
+        let palette = picker.global::<Palette>();
+
+        for chosen in [
+            PickerStyle::Classic,
+            PickerStyle::Sheet,
+            PickerStyle::Compact,
+            PickerStyle::Bear,
+        ] {
+            style(&picker, chosen);
+            dress_for(&picker, true);
+            assert!(palette.get_solid());
+            assert!(!palette.get_clear());
+            assert!(!palette.get_see_through());
+            assert_eq!(picker.get_halo(), 0.0);
+            assert_eq!(
+                crate::mascot::rise(&picker),
+                0.0,
+                "{chosen:?} shows no bear"
+            );
+        }
+        assert!(
+            !wear_backdrop(&picker, 0),
+            "the opaque sheet keeps its size"
+        );
+
+        style(&picker, PickerStyle::Bear);
+        dress_for(&picker, false);
+        assert!(!palette.get_solid());
+        assert!(crate::mascot::rise(&picker) > 0.0, "the bear is back");
+    }
 }

crates/linkunbound-shell/src/main.rs

@@ -506,6 +506,7 @@ fn present(picker: &Picker, words: &Strings, shown: &Rc<RefCell<Shown>>, arrival
     else {
         return false;
     };
+    look::settle(picker);
     let label = source.as_ref().map(|origin| origin.label.as_str());
     let listed = rows(physical_icon_side(picker));
     if listed.is_empty() {
@@ -522,14 +523,7 @@ fn present(picker: &Picker, words: &Strings, shown: &Rc<RefCell<Shown>>, arrival
         }
         look::beside_the_pointer(picker);
         let _ = picker.show();
-        if let Some(handle) = native_handle(picker.window()) {
-            host::keep_off_the_taskbar(handle, look::corner_of(picker));
-            if look::wear_backdrop(picker, handle) {
-                look::beside_the_pointer(picker);
-            }
-            look::follow(picker);
-            host::take_the_keyboard(handle);
-        }
+        look::dress_the_window(picker);
         return true;
     }
     dress(picker, words, &url, label, &listed);
@@ -548,14 +542,7 @@ fn present(picker: &Picker, words: &Strings, shown: &Rc<RefCell<Shown>>, arrival
     if let Some(ui) = ui() {
         ui.appeared.set(Some(std::time::Instant::now()));
     }
-    if let Some(handle) = native_handle(picker.window()) {
-        host::keep_off_the_taskbar(handle, look::corner_of(picker));
-        if look::wear_backdrop(picker, handle) {
-            look::beside_the_pointer(picker);
-        }
-        look::follow(picker);
-        host::take_the_keyboard(handle);
-    }
+    look::dress_the_window(picker);
     // The window reports a scale of one until it exists, which is only now: the first picker of
     // a session on a dense display was placed for a window two thirds its size, and drew icons
     // asked for at the wrong side.

crates/linkunbound-shell/src/mascot.rs

@@ -1,6 +1,6 @@
 //! The bear that peeks over the picker: its head under the glass, its paws on the edge.
 
-use linkunbound_shell::{BearHead, BearPaws, Look, Picker};
+use linkunbound_shell::{BearHead, BearPaws, Look, Palette, Picker};
 use slint::ComponentHandle;
 
 /// Sizes in logical pixels: the head, how far it rises over the edge, a paw, the room between
@@ -25,10 +25,12 @@ const COMPACT: Pose = Pose {
     gap: 46.0,
 };
 
-/// The pose the look calls for, if the bear shows at all: only over the glass, since on a painted
 /// The pose the look calls for, if the bear shows at all. Its head sits under the picker, so on
 /// glass the hidden half shows blurred and on a painted sheet it is simply behind it.
 fn pose(picker: &Picker) -> Option<&'static Pose> {
+    if picker.global::<Palette>().get_solid() {
+        return None;
+    }
     match picker.get_look() {
         Look::Bear => Some(&BEAR),
         Look::Compact => Some(&COMPACT),

crates/linkunbound-shell/ui/parts.slint

@@ -24,6 +24,8 @@ export global Palette {
     in property <float> tint: 0.77;
     // DWM rounds Acrylic at its own 8px; on macOS the glass view is cut to the sheet's corner.
     in property <length> glass-corner: 8px;
+    // Windows blends no window: the opaque sheet fills it.
+    in property <bool> solid: false;
     out property <brush> veil: light
         ? @linear-gradient(180deg, #FFFFFF.with-alpha(tint) 0%, #F3F5F9.with-alpha(tint + 0.03) 100%)
         : @linear-gradient(180deg, #282B36.with-alpha(tint) 0%, #1A1C23.with-alpha(tint + 0.03) 100%);

crates/linkunbound-shell/ui/shell.slint

@@ -237,7 +237,7 @@ export component Picker inherits Window {
             y: root.halo;
             width: root.sheet-width;
             height: root.sheet-height;
-            border-radius: Palette.clear ? Palette.glass-corner : (root.look == Look.list ? 10px : 14px);
+            border-radius: Palette.clear || Palette.solid ? Palette.glass-corner : (root.look == Look.list ? 10px : 14px);
             background: Palette.clear ? Palette.veil : Palette.pane;
             border-width: Palette.clear && !root.private-on ? 0px : 1px;
             border-color: root.private-on ? Palette.secret : Palette.glow;

crates/linkunbound-win/Cargo.toml

@@ -29,6 +29,7 @@ windows = { version = "0.62", features = [
   "Win32_Security_Authorization",
   "Win32_System_IO",
   "Win32_System_Pipes",
+  "Win32_System_Power",
   "Win32_System_RemoteDesktop",
   "Win32_System_Threading",
   "Win32_UI_Shell",
@@ -38,6 +39,7 @@ windows = { version = "0.62", features = [
   "Win32_System_Memory",
   "Win32_System_Ole",
   "Win32_Storage_FileSystem",
+  "Win32_UI_Accessibility",
   "Win32_UI_Controls",
   "Win32_UI_Input_KeyboardAndMouse",
   "Win32_UI_WindowsAndMessaging",

crates/linkunbound-win/src/lib.rs

@@ -15,17 +15,17 @@ pub use detect::installed_browsers;
 pub use icons::cached_or_extract as icon_for;
 #[cfg(windows)]
 pub use native::{
-    attach_parent_console, copy_text, current_session, current_user_sid, cursor, digit_behind,
-    front_is_ours, front_window, is_in_front, keep_off_the_taskbar,
+    attach_parent_console, blends_windows, copy_text, current_session, current_user_sid, cursor,
+    digit_behind, front_is_ours, front_window, is_in_front, keep_off_the_taskbar,
     let_whoever_opens_next_come_forward, never_activates, notify_associations_changed,
     shift_is_down, source_app, strip_title_icon, take_the_keyboard, tuck_under, wear_acrylic,
-    work_area_at, write_line_to_pipe,
+    wear_solid, work_area_at, write_line_to_pipe,
 };
 #[cfg(windows)]
 pub use registration::{
-    Registration, acrylic_is_available, association_report, default_apps_page, is_build_tree,
-    is_default_browser, sweep_legacy_edge_capture, taskbar_is_light, transparency_is_on,
-    windows_are_light,
+    Registration, acrylic_is_available, association_report, default_apps_page, dwm_rounds_corners,
+    is_build_tree, is_default_browser, sweep_legacy_edge_capture, taskbar_is_light,
+    transparency_is_on, windows_are_light,
 };
 #[cfg(windows)]
 pub use startup::{