Introduce Border struct analogous to Shadow

graphics/src/damage.rs

@@ -78,11 +78,7 @@ impl<T: Damage> Damage for Primitive<T> {
                 // damage bounds (?)
                 raw.clip_bounds.expand(1.5)
             }
-            Self::Quad {
-                bounds,
-                shadow: Some(shadow),
-                ..
-            } => {
+            Self::Quad { bounds, shadow, .. } if shadow.color.a > 0.0 => {
                 let bounds_with_shadow = Rectangle {
                     x: bounds.x + shadow.offset.x.min(0.0) - shadow.blur_radius,
                     y: bounds.y + shadow.offset.y.min(0.0) - shadow.blur_radius,

graphics/src/primitive.rs

@@ -4,7 +4,7 @@ use crate::core::image;
 use crate::core::svg;
 use crate::core::text;
 use crate::core::{
-    Background, Color, Font, Pixels, Point, Rectangle, Shadow, Vector,
+    Background, Border, Color, Font, Pixels, Point, Rectangle, Shadow, Vector,
 };
 use crate::text::editor;
 use crate::text::paragraph;
@@ -67,14 +67,10 @@ pub enum Primitive<T> {
         bounds: Rectangle,
         /// The background of the quad
         background: Background,
-        /// The border radii of the quad
-        border_radius: [f32; 4],
-        /// The border width of the quad
-        border_width: f32,
-        /// The border color of the quad
-        border_color: Color,
+        /// The [`Border`] of the quad
+        border: Border,
         /// The [`Shadow`] of the quad
-        shadow: Option<Shadow>,
+        shadow: Shadow,
     },
     /// An image primitive
     Image {

graphics/src/renderer.rs

@@ -124,9 +124,7 @@ impl<B: Backend, T> iced_core::Renderer for Renderer<B, T> {
         self.primitives.push(Primitive::Quad {
             bounds: quad.bounds,
             background: background.into(),
-            border_radius: quad.border_radius.into(),
-            border_width: quad.border_width,
-            border_color: quad.border_color,
+            border: quad.border,
             shadow: quad.shadow,
         });
     }