Introduce Border struct analogous to Shadow

core/src/border.rs

@@ -0,0 +1,54 @@
+//! Draw lines around containers.
+use crate::Color;
+
+/// A border.
+#[derive(Debug, Clone, Copy, PartialEq, Default)]
+pub struct Border {
+    /// The color of the border.
+    pub color: Color,
+
+    /// The width of the border.
+    pub width: f32,
+
+    /// The radius of the border.
+    pub radius: Radius,
+}
+
+impl Border {
+    /// Creates a new default [`Border`] with the given [`Radius`].
+    pub fn with_radius(radius: impl Into<Radius>) -> Self {
+        Self {
+            radius: radius.into(),
+            ..Self::default()
+        }
+    }
+}
+
+/// The border radii for the corners of a graphics primitive in the order:
+/// top-left, top-right, bottom-right, bottom-left.
+#[derive(Debug, Clone, Copy, PartialEq, Default)]
+pub struct Radius([f32; 4]);
+
+impl From<f32> for Radius {
+    fn from(w: f32) -> Self {
+        Self([w; 4])
+    }
+}
+
+impl From<u8> for Radius {
+    fn from(w: u8) -> Self {
+        Self([f32::from(w); 4])
+    }
+}
+
+impl From<[f32; 4]> for Radius {
+    fn from(radi: [f32; 4]) -> Self {
+        Self(radi)
+    }
+}
+
+impl From<Radius> for [f32; 4] {
+    fn from(radi: Radius) -> Self {
+        radi.0
+    }
+}

core/src/element.rs

@@ -6,7 +6,8 @@ use crate::renderer;
 use crate::widget;
 use crate::widget::tree::{self, Tree};
 use crate::{
-    Clipboard, Color, Layout, Length, Rectangle, Shell, Size, Vector, Widget,
+    Border, Clipboard, Color, Layout, Length, Rectangle, Shell, Size, Vector,
+    Widget,
 };
 
 use std::any::Any;
@@ -537,8 +538,11 @@ where
             renderer.fill_quad(
                 renderer::Quad {
                     bounds: layout.bounds(),
-                    border_color: color,
-                    border_width: 1.0,
+                    border: Border {
+                        color,
+                        width: 1.0,
+                        ..Border::default()
+                    },
                     ..renderer::Quad::default()
                 },
                 Color::TRANSPARENT,

core/src/lib.rs

@@ -17,6 +17,7 @@
     rustdoc::broken_intra_doc_links
 )]
 pub mod alignment;
+pub mod border;
 pub mod clipboard;
 pub mod event;
 pub mod font;
@@ -27,7 +28,6 @@ pub mod layout;
 pub mod mouse;
 pub mod overlay;
 pub mod renderer;
-pub mod shadow;
 pub mod svg;
 pub mod text;
 pub mod time;
@@ -37,7 +37,6 @@ pub mod window;
 
 mod angle;
 mod background;
-mod border_radius;
 mod color;
 mod content_fit;
 mod element;
@@ -47,6 +46,7 @@ mod padding;
 mod pixels;
 mod point;
 mod rectangle;
+mod shadow;
 mod shell;
 mod size;
 mod vector;
@@ -54,7 +54,7 @@ mod vector;
 pub use alignment::Alignment;
 pub use angle::{Degrees, Radians};
 pub use background::Background;
-pub use border_radius::BorderRadius;
+pub use border::Border;
 pub use clipboard::Clipboard;
 pub use color::Color;
 pub use content_fit::ContentFit;

core/src/renderer.rs

@@ -5,7 +5,7 @@ mod null;
 #[cfg(debug_assertions)]
 pub use null::Null;
 
-use crate::{Background, BorderRadius, Color, Rectangle, Shadow, Size, Vector};
+use crate::{Background, Border, Color, Rectangle, Shadow, Size, Vector};
 
 /// A component that can be used by widgets to draw themselves on a screen.
 pub trait Renderer: Sized {
@@ -37,27 +37,19 @@ pub struct Quad {
     /// The bounds of the [`Quad`].
     pub bounds: Rectangle,
 
-    /// The border radius of the [`Quad`].
-    pub border_radius: BorderRadius,
+    /// The [`Border`] of the [`Quad`].
+    pub border: Border,
 
-    /// The border width of the [`Quad`].
-    pub border_width: f32,
-
-    /// The border color of the [`Quad`].
-    pub border_color: Color,
-
-    /// The shadow of the [`Quad`].
-    pub shadow: Option<Shadow>,
+    /// The [`Shadow`] of the [`Quad`].
+    pub shadow: Shadow,
 }
 
 impl Default for Quad {
     fn default() -> Self {
         Self {
             bounds: Rectangle::with_size(Size::ZERO),
-            border_radius: 0.0.into(),
-            border_width: 0.0,
-            border_color: Color::TRANSPARENT,
-            shadow: None,
+            border: Border::default(),
+            shadow: Shadow::default(),
         }
     }
 }

core/src/shadow.rs

@@ -1,15 +1,14 @@
-//! Shadow
 use crate::{Color, Vector};
 
-/// A shadow
-#[derive(Debug, Clone, Copy, PartialEq)]
+/// A shadow.
+#[derive(Debug, Clone, Copy, PartialEq, Default)]
 pub struct Shadow {
-    /// The color of the shadow
+    /// The color of the shadow.
     pub color: Color,
 
-    /// The offset of the shadow
+    /// The offset of the shadow.
     pub offset: Vector,
 
-    /// The blur radius of the shadow
+    /// The blur radius of the shadow.
     pub blur_radius: f32,
 }