Refactor fill color stuff

hui/src/element/builtin/slider.rs

@@ -8,7 +8,7 @@ use crate::{
   element::{MeasureContext, ProcessContext, UiElement},
   layout::{Size2d, compute_size},
   measure::Response,
-  rectangle::CornersColors,
+  rectangle::FillColor,
   signal::{trigger::SignalTriggerArg, Signal},
 };
 
@@ -42,11 +42,11 @@ pub struct Slider {
 
   /// Color of the slider handle
   #[setters(into)]
-  pub handle_color: CornersColors,
+  pub handle_color: FillColor,
 
   /// Color of the slider track
   #[setters(into)]
-  pub track_color: CornersColors,
+  pub track_color: FillColor,
 
   /// Follow mode
   pub follow_mode: SliderFollowMode,

hui/src/rectangle.rs

@@ -7,4 +7,7 @@ mod sides;
 pub use sides::Sides;
 
 mod corners;
-pub use corners::{Corners, CornersColors};
+pub use corners::Corners;
+
+mod color;
+pub use color::FillColor;

hui/src/rectangle/color.rs

@@ -1,72 +1,122 @@
 use super::Corners;
 use glam::{Vec3, Vec4, vec4};
 
-/// Like Corners, but specialized for colors\
+/// Represents the fill color of a rectangle
-/// Opaque type, needs to be casted to `Corners<Vec4>` to be used
+///
+/// Can be a single color or a simple gradient with different colors for each corner
 #[derive(Clone, Copy, Debug, PartialEq)]
-pub struct CornersColors(Corners<Vec4>);
+pub struct FillColor(Corners<Vec4>);
 
-impl Default for CornersColors {
+impl FillColor {
+  pub const fn new(corners: Corners<Vec4>) -> Self {
+    Self(corners)
+  }
+
+  /// Transparent background (alpha = 0)
+  pub const TRANSPARENT: Self = Self::rgba(0., 0., 0., 0.);
+
+  /// Transparent background (alpha = 0)
+  pub const fn transparent() -> Self {
+    Self::TRANSPARENT
+  }
+
+  /// Check if the fill color is completely transparent
+  ///
+  /// (i.e. all corners have an alpha value of 0.0)
+  pub fn is_transparent(&self) -> bool {
+    self.0.top_left.w == 0. &&
+    self.0.top_right.w == 0. &&
+    self.0.bottom_left.w == 0. &&
+    self.0.bottom_right.w == 0.
+  }
+
+  /// Construct a solid color fill from values representing the red, green, blue and alpha channels
+  pub const fn rgba(r: f32, g: f32, b: f32, a: f32) -> Self {
+    Self(Corners {
+      top_left: vec4(r, g, b, a),
+      top_right: vec4(r, g, b, a),
+      bottom_left: vec4(r, g, b, a),
+      bottom_right: vec4(r, g, b, a),
+    })
+  }
+
+  /// Construct a solid color fill from three values representing the red, green and blue channels
+  pub const fn rgb(r: f32, g: f32, b: f32) -> Self {
+    Self(Corners {
+      top_left: vec4(r, g, b, 1.0),
+      top_right: vec4(r, g, b, 1.0),
+      bottom_left: vec4(r, g, b, 1.0),
+      bottom_right: vec4(r, g, b, 1.0),
+    })
+  }
+
+  /// Construct a simple gradient fill from four colors representing the corners of the rectangle
+  pub const fn corners(top_left: Vec4, top_right: Vec4, bottom_left: Vec4, bottom_right: Vec4) -> Self {
+    Self(Corners { top_left, top_right, bottom_left, bottom_right })
+  }
+}
+
+impl Default for FillColor {
   fn default() -> Self {
     Self(Corners::all(vec4(0.0, 0.0, 0.0, 1.0)))
   }
 }
 
-impl From<Corners<Vec4>> for CornersColors {
+impl From<Corners<Vec4>> for FillColor {
   fn from(corners: Corners<Vec4>) -> Self {
     Self(corners)
   }
 }
 
-impl From<CornersColors> for Corners<Vec4> {
+impl From<FillColor> for Corners<Vec4> {
-  fn from(corners: CornersColors) -> Self {
+  fn from(corners: FillColor) -> Self {
     corners.0
   }
 }
 
-impl From<Vec4> for CornersColors {
+impl From<Vec4> for FillColor {
   fn from(value: Vec4) -> Self {
     Self(Corners::all(value))
   }
 }
 
-impl From<(f32, f32, f32, f32)> for CornersColors {
+impl From<(f32, f32, f32, f32)> for FillColor {
   fn from((r, g, b, a): (f32, f32, f32, f32)) -> Self {
     Self(Corners::all(vec4(r, g, b, a)))
   }
 }
 
-impl From<[f32; 4]> for CornersColors {
+impl From<[f32; 4]> for FillColor {
   fn from([r, g, b, a]: [f32; 4]) -> Self {
     Self(Corners::all(vec4(r, g, b, a)))
   }
 }
 
-impl From<Vec3> for CornersColors {
+impl From<Vec3> for FillColor {
   fn from(value: Vec3) -> Self {
     Self(Corners::all(vec4(value.x, value.y, value.z, 1.0)))
   }
 }
 
-impl From<(f32, f32, f32)> for CornersColors {
+impl From<(f32, f32, f32)> for FillColor {
   fn from((r, g, b): (f32, f32, f32)) -> Self {
     Self(Corners::all(vec4(r, g, b, 1.0)))
   }
 }
 
-impl From<[f32; 3]> for CornersColors {
+impl From<[f32; 3]> for FillColor {
   fn from([r, g, b]: [f32; 3]) -> Self {
     Self(Corners::all(vec4(r, g, b, 1.0)))
   }
 }
 
-impl From<(Vec4, Vec4, Vec4, Vec4)> for CornersColors {
+impl From<(Vec4, Vec4, Vec4, Vec4)> for FillColor {
   fn from((top_left, top_right, bottom_left, bottom_right): (Vec4, Vec4, Vec4, Vec4)) -> Self {
     Self(Corners { top_left, top_right, bottom_left, bottom_right })
   }
 }
 
-impl From<((f32, f32, f32, f32), (f32, f32, f32, f32), (f32, f32, f32, f32), (f32, f32, f32, f32))> for CornersColors {
+impl From<((f32, f32, f32, f32), (f32, f32, f32, f32), (f32, f32, f32, f32), (f32, f32, f32, f32))> for FillColor {
   fn from(value: ((f32, f32, f32, f32), (f32, f32, f32, f32), (f32, f32, f32, f32), (f32, f32, f32, f32))) -> Self {
     Self(Corners {
       top_left: vec4(value.0.0, value.0.1, value.0.2, value.0.3),
@@ -77,7 +127,7 @@ impl From<((f32, f32, f32, f32), (f32, f32, f32, f32), (f32, f32, f32, f32), (f3
   }
 }
 
-impl From<[[f32; 4]; 4]> for CornersColors {
+impl From<[[f32; 4]; 4]> for FillColor {
   fn from(value: [[f32; 4]; 4]) -> Self {
     Self(Corners {
       top_left: vec4(value[0][0], value[0][1], value[0][2], value[0][3]),
@@ -88,7 +138,7 @@ impl From<[[f32; 4]; 4]> for CornersColors {
   }
 }
 
-impl From<(Vec3, Vec3, Vec3, Vec3)> for CornersColors {
+impl From<(Vec3, Vec3, Vec3, Vec3)> for FillColor {
   fn from((top_left, top_right, bottom_left, bottom_right): (Vec3, Vec3, Vec3, Vec3)) -> Self {
     Self(Corners {
       top_left: vec4(top_left.x, top_left.y, top_left.z, 1.0),
@@ -99,7 +149,7 @@ impl From<(Vec3, Vec3, Vec3, Vec3)> for CornersColors {
   }
 }
 
-impl From<((f32, f32, f32), (f32, f32, f32), (f32, f32, f32), (f32, f32, f32))> for CornersColors {
+impl From<((f32, f32, f32), (f32, f32, f32), (f32, f32, f32), (f32, f32, f32))> for FillColor {
   fn from(value: ((f32, f32, f32), (f32, f32, f32), (f32, f32, f32), (f32, f32, f32))) -> Self {
     Self(Corners {
       top_left: vec4(value.0.0, value.0.1, value.0.2, 1.0),
@@ -110,7 +160,7 @@ impl From<((f32, f32, f32), (f32, f32, f32), (f32, f32, f32), (f32, f32, f32))>
   }
 }
 
-impl From<[[f32; 3]; 4]> for CornersColors {
+impl From<[[f32; 3]; 4]> for FillColor {
   fn from(value: [[f32; 3]; 4]) -> Self {
     Self(Corners {
       top_left: vec4(value[0][0], value[0][1], value[0][2], 1.0),

hui/src/rectangle/corners.rs

@@ -1,6 +1,3 @@
-mod corners_colors;
-pub use corners_colors::CornersColors;
-
 /// Represents 4 corners of a rectangular shape.
 #[derive(Clone, Copy, Debug, PartialEq, Eq, Default)]
 pub struct Corners<T> {