MichaelFenwick · Dec 29, 2023 · Dec 29, 2023
diff --git a/lib/cielab_color.dart b/lib/cielab_color.dart
@@ -36,6 +36,8 @@ class CielabColor extends Color {
     return XyzColor(xyz['x']!, xyz['y']!, xyz['z']!);
   }
 
+  RgbaColor toRgbaColor() => this.toRgbColor().toRgbaColor();
+
   @override
   CielabColor toCielabColor() => this;
 

diff --git a/lib/color.dart b/lib/color.dart
@@ -7,13 +7,23 @@ library color;
 import 'dart:math';
 
 part 'cielab_color.dart';
+
 part 'color_filter.dart';
+
 part 'color_parser.dart';
+
 part 'css_color_space.dart';
+
 part 'hex_color.dart';
+
 part 'hsl_color.dart';
+
 part 'hsv_color.dart';
+
 part 'rgb_color.dart';
+
+part 'rgba_color.dart';
+
 part 'xyz_color.dart';
 
 /// An object representing a color.
@@ -23,28 +33,44 @@ part 'xyz_color.dart';
 /// [Color]s can be directly compared using the `==` operator, which will return true if the two [Color] objects represent the same RGB color.
 abstract class Color {
   const Color();
+
   const factory Color.rgb(num r, num g, num b) = RgbColor;
+
+  const factory Color.rgba(num r, num g, num b, num a) = RgbaColor;
+
   factory Color.hex(String hexCode) = HexColor;
+
   const factory Color.hsl(num h, num s, num l) = HslColor;
+
   const factory Color.hsv(num h, num s, num v) = HsvColor;
+
   const factory Color.xyz(num x, num y, num z) = XyzColor;
+
   const factory Color.cielab(num l, num a, num b) = CielabColor;
 
   RgbColor toRgbColor();
+
+  RgbaColor toRgbaColor();
+
   HexColor toHexColor() => toRgbColor().toHexColor();
+
   HslColor toHslColor();
+
   HsvColor toHsvColor();
+
   XyzColor toXyzColor();
+
   CielabColor toCielabColor();
 
   @override
   String toString();
+
   Map<String, num> toMap();
 
   @override
   int get hashCode {
-    var rgb = toRgbColor();
-    return 256 * 256 * rgb.r.toInt() + 256 * rgb.g.toInt() + rgb.b.toInt();
+    RgbaColor rgba = this.toRgbaColor();
+    return (pow(2, 30) * rgba.a).round() + 256 * 256 * rgba.r.toInt() + 256 * rgba.g.toInt() + rgba.b.toInt();
   }
 
   @override
@@ -71,6 +97,8 @@ abstract class Color {
       return toXyzColor();
     } else if (colorType is CielabColor) {
       return toCielabColor();
+    } else if (colorType is RgbaColor) {
+      return toRgbaColor();
     } else {
       return this;
     }

diff --git a/lib/hsl_color.dart b/lib/hsl_color.dart
@@ -64,6 +64,8 @@ class HslColor extends Color implements CssColorSpace {
     return RgbColor(rgb[0], rgb[1], rgb[2]);
   }
 
+  RgbaColor toRgbaColor() => this.toRgbColor().toRgbaColor();
+
   @override
   HslColor toHslColor() => this;
 

diff --git a/lib/hsv_color.dart b/lib/hsv_color.dart
@@ -28,6 +28,8 @@ class HsvColor extends Color {
   @override
   RgbColor toRgbColor() => toHslColor().toRgbColor();
 
+  RgbaColor toRgbaColor() => this.toRgbColor().toRgbaColor();
+
   @override
   HslColor toHslColor() {
     num hsvSaturation = s / 100;

diff --git a/lib/rgb_color.dart b/lib/rgb_color.dart
@@ -30,6 +30,8 @@ class RgbColor extends Color implements CssColorSpace {
   @override
   RgbColor toRgbColor() => this;
 
+  RgbaColor toRgbaColor() => RgbaColor(r, g, b, 1);
+
   @override
   HslColor toHslColor() {
     var rf = r / 255;

diff --git a/lib/rgba_color.dart b/lib/rgba_color.dart
@@ -0,0 +1,36 @@
+part of color;
+
+class RgbaColor extends RgbColor {
+  static const int aMin = 0;
+  static const int aMax = 1;
+
+  final num a;
+
+  /**
+   * Creates a [Color] using a vector describing its red, green, blue and alpha
+   * values.
+   *
+   * The value for [r], [g], and [b] should be in the range between 0 and
+   * 255 (inclusive). Values above this range will be assumed to be a value
+   * of 255, and values below this range will be assumed to be a value of 0.
+   * The value for [a] should be between 0 and 1 (1 means
+   * opaque).
+   *
+   * Note that when converting an [RgbaColor] to a different color model that
+   * doesn't provide alpha information, the alpha data [a] will be dropped.
+   */
+  const RgbaColor(num r, num g, num b, this.a) : super(r, g, b);
+
+
+  RgbaColor toRgbaColor() => this;
+
+  String toString() => "r: $r, g: $g, b: $b, a: $a";
+
+  String toCssString() => 'rgba($r, $g, $b, $a)';
+
+  Map<String, int> toMap() {
+    return {'r': r.toInt(), 'g': g.toInt(), 'b': b.toInt(), 'a': a.toInt()};
+  }
+
+  RgbaColor clone() => RgbaColor(this.r, this.g, this.b, this.a);
+}
diff --git a/lib/xyz_color.dart b/lib/xyz_color.dart
@@ -33,6 +33,8 @@ class XyzColor extends Color {
     return RgbColor(rgb['r']!, rgb['g']!, rgb['b']!);
   }
 
+  RgbaColor toRgbaColor() => this.toRgbColor().toRgbaColor();
+
   @override
   HslColor toHslColor() => toRgbColor().toHslColor();
 

diff --git a/pubspec.yaml b/pubspec.yaml
@@ -8,9 +8,9 @@ authors:
 homepage: https://github.com/MichaelFenwick/Color
 
 environment:
-  sdk: '>=2.12.0 <3.0.0'
+  sdk: '>=2.12.0 <4.0.0'
 dev_dependencies:
-  build_runner: ^1.6.2
-  build_web_compilers: ^2.12.0
-  pedantic: ^1.11.0
-  test: ^1.16.5
+  build_runner:
+  build_web_compilers:
+  lints: ^2.0.0
+  test: ^1.21.0
diff --git a/test/color_test.dart b/test/color_test.dart
@@ -10,6 +10,14 @@ void main() {
       expect(color.g, equals(255));
       expect(color.b, equals(238));
     });
+    test("through the Color.rgba constructor", () {
+      var color = Color.rgba(192, 255, 238, 0.5) as RgbaColor;
+      expect(color is Color, isTrue);
+      expect(color.r, equals(192));
+      expect(color.g, equals(255));
+      expect(color.b, equals(238));
+      expect(color.a, equals(0.5));
+    });
     test('through the Color.hex constructor', () {
       var color = Color.hex('c0ffee') as HexColor;
       expect(color is Color, isTrue);
@@ -52,6 +60,14 @@ void main() {
       expect(color.g, equals(255));
       expect(color.b, equals(238));
     });
+    test("as an RgbaColor", () {
+      var color = RgbaColor(192, 255, 238, 0.5);
+      expect(color is Color, isTrue);
+      expect(color.r, equals(192));
+      expect(color.g, equals(255));
+      expect(color.b, equals(238));
+      expect(color.a, equals(0.5));
+    });
     test('as a HexColor', () {
       var color = HexColor('c0ffee');
       expect(color is Color, isTrue);
@@ -101,6 +117,11 @@ void main() {
       var string = color.toString();
       expect(string, equals('r: 192, g: 255, b: 238'));
     });
+    test("from an RgbaColor", () {
+      var color = const Color.rgba(192, 255, 238, 0.5);
+      String string = color.toString();
+      expect(string, equals('r: 192, g: 255, b: 238, a: 0.5'));
+    });
     test('from a HexColor', () {
       var color = Color.hex('c0ffee');
       var string = color.toString();
@@ -139,6 +160,11 @@ void main() {
       var string = color.toCssString();
       expect(string, equals('rgb(192, 255, 238)'));
     });
+    test("from an RgbaColor", () {
+      var color = const Color.rgba(192, 255, 238, 0.5) as RgbColor;
+      String string = color.toCssString();
+      expect(string, equals('rgba(192, 255, 238, 0.5)'));
+    });
     test('from a HexColor', () {
       var color = Color.hex('c0ffee') as HexColor;
       var string = color.toCssString();
@@ -176,13 +202,15 @@ void main() {
   });
   group('Colors can be converted', () {
     late RgbColor rgb;
+    late RgbaColor rgba;
     late HexColor hex;
     late HslColor hsl;
     late HsvColor hsv;
     late XyzColor xyz;
     late CielabColor cielab;
     setUp(() {
       rgb = const RgbColor(192, 255, 238);
+      rgba = const RgbaColor(192, 255, 238, 1);
       hex = HexColor('c0ffee');
       hsl = const HslColor(163.8, 100, 87.6);
       hsv = const HsvColor(163.8, 24.7, 100);
@@ -194,6 +222,10 @@ void main() {
       var conversion = rgb.toHexColor();
       expect(conversion, equals(hex));
     });
+    test('from rgb to rgba', () {
+      var conversion = rgb.toRgbaColor();
+      expect(conversion, equals(rgba));
+    });
     test('from rgb to hsl', () {
       var conversion = rgb.toHslColor();
       expect(conversion, equals(hsl));
@@ -211,10 +243,35 @@ void main() {
       expect(conversion, equals(cielab));
     });
 
+    test("from rgba to rgb", () {
+      RgbColor conversion = rgba.toRgbColor();
+      expect(conversion, equals(rgb));
+    });
+    test("from rgba to hex", () {
+      HexColor conversion = rgba.toHexColor();
+      expect(conversion, equals(hex));
+    });
+    test("from rgba to hsl", () {
+      HslColor conversion = rgba.toHslColor();
+      expect(conversion, equals(hsl));
+    });
+    test("from rgba to xyz", () {
+      XyzColor conversion = rgba.toXyzColor();
+      expect(conversion, equals(xyz));
+    });
+    test("from rgba to cielab", () {
+      CielabColor conversion = rgba.toCielabColor();
+      expect(conversion, equals(cielab));
+    });
+
     test('from hex to rgb', () {
       var conversion = hex.toRgbColor();
       expect(conversion, equals(rgb));
     });
+    test('from hex to rgba', () {
+      var conversion = hex.toRgbaColor();
+      expect(conversion, equals(rgba));
+    });
     test('from hex to hsl', () {
       var conversion = hex.toHslColor();
       expect(conversion, equals(hsl));
@@ -236,6 +293,10 @@ void main() {
       var conversion = hsl.toRgbColor();
       expect(conversion, equals(rgb));
     });
+    test('from hsl to rgba', () {
+      var conversion = hsl.toRgbaColor();
+      expect(conversion, equals(rgba));
+    });
     test('from hsl to hsv', () {
       var conversion = hsl.toHsvColor();
       expect(conversion, equals(hsv));
@@ -253,6 +314,10 @@ void main() {
       var conversion = hsv.toRgbColor();
       expect(conversion, equals(rgb));
     });
+    test('from hsv to rgba', () {
+      var conversion = hsv.toRgbaColor();
+      expect(conversion, equals(rgba));
+    });
     test('from hsv to hsl', () {
       var conversion = hsv.toHslColor();
       expect(conversion, equals(hsl));
@@ -270,6 +335,10 @@ void main() {
       var conversion = xyz.toRgbColor();
       expect(conversion, equals(rgb));
     });
+    test('from xyz to rgba', () {
+      var conversion = xyz.toRgbaColor();
+      expect(conversion, equals(rgba));
+    });
     test('from xyz to hsl', () {
       var conversion = xyz.toHslColor();
       expect(conversion, equals(hsl));
@@ -287,6 +356,10 @@ void main() {
       var conversion = cielab.toRgbColor();
       expect(conversion, equals(rgb));
     });
+    test('from cielab to rgba', () {
+      var conversion = cielab.toRgbaColor();
+      expect(conversion, equals(rgba));
+    });
     test('from cielab to hsl', () {
       var conversion = cielab.toHslColor();
       expect(conversion, equals(hsl));