bevy_color: adding 'palettes' module. (bevyengine#12067)

Two palettes are added:
- Basic: A basic palette with 16 colors.
- CSS: A palette with the colors from the "extended CSS"/X11/HTML4.0
color names.

crates/bevy_color/src/color_range.rs

@@ -22,17 +22,18 @@ impl<T: Mix> ColorRange<T> for Range<T> {
 #[cfg(test)]
 mod tests {
     use super::*;
+    use crate::palettes::basic;
     use crate::{LinearRgba, Srgba};
 
     #[test]
     fn test_color_range() {
-        let range = Srgba::RED..Srgba::BLUE;
-        assert_eq!(range.at(0.0), Srgba::RED);
+        let range = basic::RED..basic::BLUE;
+        assert_eq!(range.at(0.0), basic::RED);
         assert_eq!(range.at(0.5), Srgba::new(0.5, 0.0, 0.5, 1.0));
-        assert_eq!(range.at(1.0), Srgba::BLUE);
+        assert_eq!(range.at(1.0), basic::BLUE);
 
-        let lred: LinearRgba = Srgba::RED.into();
-        let lblue: LinearRgba = Srgba::BLUE.into();
+        let lred: LinearRgba = basic::RED.into();
+        let lblue: LinearRgba = basic::BLUE.into();
 
         let range = lred..lblue;
         assert_eq!(range.at(0.0), lred);

crates/bevy_color/src/lib.rs

@@ -72,6 +72,7 @@ mod hsla;
 mod lcha;
 mod linear_rgba;
 mod oklaba;
+pub mod palettes;
 mod srgba;
 #[cfg(test)]
 mod test_colors;

crates/bevy_color/src/palettes/basic.rs

@@ -0,0 +1,39 @@
+//! Named colors from the CSS1 specification, also known as
+//! [basic colors](https://en.wikipedia.org/wiki/Web_colors#Basic_colors).
+//! This is the same set of colors used in the
+//! [VGA graphcs standard](https://en.wikipedia.org/wiki/Video_Graphics_Array).
+
+use crate::Srgba;
+
+/// <div style="background-color:rgb(0%, 0%, 0%); width: 10px; padding: 10px; border: 1px solid;"></div>
+pub const BLACK: Srgba = Srgba::new(0.0, 0.0, 0.0, 1.0);
+/// <div style="background-color:rgb(0%, 0%, 100%); width: 10px; padding: 10px; border: 1px solid;"></div>
+pub const BLUE: Srgba = Srgba::new(0.0, 0.0, 1.0, 1.0);
+/// <div style="background-color:rgb(0%, 100%, 100%); width: 10px; padding: 10px; border: 1px solid;"></div>
+pub const CYAN: Srgba = Srgba::new(0.0, 1.0, 1.0, 1.0);
+/// <div style="background-color:rgb(0%, 50%, 0%); width: 10px; padding: 10px; border: 1px solid;"></div>
+pub const GREEN: Srgba = Srgba::new(0.0, 0.5, 0.0, 1.0);
+/// <div style="background-color:rgb(100%, 0%, 100%); width: 10px; padding: 10px; border: 1px solid;"></div>
+pub const FUCHSIA: Srgba = Srgba::new(1.0, 0.0, 1.0, 1.0);
+/// <div style="background-color:rgb(50%, 50%, 50%); width: 10px; padding: 10px; border: 1px solid;"></div>
+pub const GRAY: Srgba = Srgba::new(0.5, 0.5, 0.5, 1.0);
+/// <div style="background-color:rgb(0%, 100%, 0%); width: 10px; padding: 10px; border: 1px solid;"></div>
+pub const LIME: Srgba = Srgba::new(0.0, 1.0, 0.0, 1.0);
+/// <div style="background-color:rgb(50%, 0%, 0%); width: 10px; padding: 10px; border: 1px solid;"></div>
+pub const MAROON: Srgba = Srgba::new(0.5, 0.0, 0.0, 1.0);
+/// <div style="background-color:rgb(0%, 0%, 50%); width: 10px; padding: 10px; border: 1px solid;"></div>
+pub const NAVY: Srgba = Srgba::new(0.0, 0.0, 0.5, 1.0);
+/// <div style="background-color:rgb(50%, 50%, 0%); width: 10px; padding: 10px; border: 1px solid;"></div>
+pub const OLIVE: Srgba = Srgba::new(0.5, 0.5, 0.0, 1.0);
+/// <div style="background-color:rgb(50%, 0%, 50%); width: 10px; padding: 10px; border: 1px solid;"></div>
+pub const PURPLE: Srgba = Srgba::new(0.5, 0.0, 0.5, 1.0);
+/// <div style="background-color:rgb(100%, 0%, 0%); width: 10px; padding: 10px; border: 1px solid;"></div>
+pub const RED: Srgba = Srgba::new(1.0, 0.0, 0.0, 1.0);
+/// <div style="background-color:rgb(75%, 75%, 75%); width: 10px; padding: 10px; border: 1px solid;"></div>
+pub const SILVER: Srgba = Srgba::new(0.75, 0.75, 0.75, 1.0);
+/// <div style="background-color:rgb(0%, 50%, 50%); width: 10px; padding: 10px; border: 1px solid;"></div>
+pub const TEAL: Srgba = Srgba::new(0.0, 0.5, 0.5, 1.0);
+/// <div style="background-color:rgb(100%, 100%, 100%); width: 10px; padding: 10px; border: 1px solid;"></div>
+pub const WHITE: Srgba = Srgba::new(1.0, 1.0, 1.0, 1.0);
+/// <div style="background-color:rgb(100%, 100%, 0%); width: 10px; padding: 10px; border: 1px solid;"></div>
+pub const YELLOW: Srgba = Srgba::new(1.0, 1.0, 0.0, 1.0);