Unify circular corner geometry and shader masks

crates/ferese-theme/src/geometry.rs

@@ -0,0 +1,19 @@
+/// Radius of a concentric inset, in the same units as the outer radius.
+pub fn inner_radius(outer: f32, padding: f32) -> f32 {
+    (outer - padding).max(0.0)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn inset_corners_preserve_the_center_and_saturate() {
+        assert_eq!(inner_radius(14.0, 4.0), 10.0);
+        assert_eq!(inner_radius(7.5, 2.25), 5.25);
+        assert_eq!(inner_radius(14.0, 0.0), 14.0);
+        assert_eq!(inner_radius(14.0, 14.0), 0.0);
+        assert_eq!(inner_radius(14.0, 20.0), 0.0);
+        assert_eq!(inner_radius(0.0, 4.0), 0.0);
+    }
+}

crates/ferese-theme/src/lib.rs

@@ -4,6 +4,7 @@ pub mod calendar;
 mod contrast;
 pub mod controls;
 pub mod gallery;
+mod geometry;
 pub mod icons;
 pub mod material;
 pub mod menus;
@@ -14,6 +15,7 @@ mod typography;
 
 pub use button::accent_button;
 pub use contrast::{accent_color, accent_pair, apply, composite, contrast, foreground, luminance};
+pub use geometry::inner_radius;
 pub use palette::{Palette, mix, parse_color, surface_shade};
 pub use presets::{PRESETS, Preset};
 pub use typography::{font, text};

crates/ferese-theme/src/menus.rs

@@ -78,20 +78,25 @@ pub fn separator<'a, M: 'a>(foreground: Color, opacity: f32) -> Element<'a, M> {
 
 pub fn switch<'a, M: 'a>(enabled: bool, palette: crate::Palette, opacity: f32) -> Element<'a, M> {
     let (track, thumb) = crate::controls::switch_colors(palette, enabled, false);
+    let track_radius = 10.;
+    let padding = 2.;
     let knob = container(cosmic::widget::Space::new().width(16).height(16))
         .width(16)
         .height(16)
-        .class(crate::controls::surface(Color { a: opacity, ..thumb }, 8.));
+        .class(crate::controls::surface(
+            Color { a: opacity, ..thumb },
+            crate::inner_radius(track_radius, padding),
+        ));
     container(knob)
         .width(36)
         .height(20)
-        .padding(2)
+        .padding(padding)
         .align_x(if enabled {
             cosmic::iced::alignment::Horizontal::Right
         } else {
             cosmic::iced::alignment::Horizontal::Left
         })
-        .class(crate::controls::surface(track.scale_alpha(opacity), 10.))
+        .class(crate::controls::surface(track.scale_alpha(opacity), track_radius))
         .into()
 }