Store RGB components of `CommonColor`internally as double instead of byte, to improve accuracy. Fixes #325.

1 files changed, 49 insertions, 31 deletions

diff --git a/Xamarin.PropertyEditing.Tests/CommonColorTests.cs b/Xamarin.PropertyEditing.Tests/CommonColorTests.cs
index f9f579f..3038f7d 100644
--- a/Xamarin.PropertyEditing.Tests/CommonColorTests.cs
+++ b/Xamarin.PropertyEditing.Tests/CommonColorTests.cs
@@ -9,30 +9,32 @@ namespace Xamarin.PropertyEditing.Tests
 	public class CommonColorTests
 	{
 		public static readonly Dictionary<string, ColorTestCase> PrimaryTestCases = new Dictionary<string, ColorTestCase> {
-			// { name,                       r    g    b   c%   m%   y%   k%    h°   l%   s%   b%  a}
-			{ "Black",   new ColorTestCase(  0,   0,   0,   0,   0,   0, 100,    0,   0,   0,   0) },
-			{ "White",   new ColorTestCase(255, 255, 255,   0,   0,   0,   0,    0, 100,   0, 100) },
-			{ "Gray",    new ColorTestCase(127, 127, 127,   0,   0,   0,  50,    0,  50,   0,  50) },
-			{ "Silver",  new ColorTestCase(191, 191, 191,   0,   0,   0,  25,    0,  75,   0,  75) },
-			{ "Red",     new ColorTestCase(255,   0,   0,   0, 100, 100,   0,    0,  50, 100, 100) },
-			{ "Lime",    new ColorTestCase(  0, 255,   0, 100,   0, 100,   0,  120,  50, 100, 100) },
-			{ "Blue",    new ColorTestCase(  0,   0, 255, 100, 100,   0,   0,  240,  50, 100, 100) },
-			{ "Yellow",  new ColorTestCase(255, 255,   0,   0,   0, 100,   0,   60,  50, 100, 100) },
-			{ "Cyan",    new ColorTestCase(  0, 255, 255, 100,   0,   0,   0,  180,  50, 100, 100) },
-			{ "Magenta", new ColorTestCase(255,   0, 255,   0, 100,   0,   0,  300,  50, 100, 100) },
-			{ "Maroon",  new ColorTestCase(127,   0,   0,   0, 100, 100,  50,    0,  25, 100,  50) },
-			{ "Green",   new ColorTestCase(  0, 127,   0, 100,   0, 100,  50,  120,  25, 100,  50) },
-			{ "Navy",    new ColorTestCase(  0,   0, 127, 100, 100,   0,  50,  240,  25, 100,  50) },
-			{ "Olive",   new ColorTestCase(127, 127,   0,   0,   0, 100,  50,   60,  25, 100,  50) },
-			{ "Purple",  new ColorTestCase(127,   0, 127,   0, 100,   0,  50,  300,  25, 100,  50) },
-			{ "Teal",    new ColorTestCase(  0, 127, 127, 100,   0,   0,  50,  180,  25, 100,  50) },
+			// { name,                       r    g    b   c%   m%   y%   k%    h°    l%   s%    b%  }
+			{ "Black",   new ColorTestCase(  0,   0,   0,   0,   0,   0, 100,    0,    0,   0,    0) },
+			{ "White",   new ColorTestCase(255, 255, 255,   0,   0,   0,   0,    0,  100,   0,  100) },
+			{ "Gray",    new ColorTestCase(128, 128, 128,   0,   0,   0,  50,    0,   50,   0,   50) },
+			{ "Silver",  new ColorTestCase(191, 191, 191,   0,   0,   0,  25,    0, 74.9,   0, 74.9) },
+			{ "Red",     new ColorTestCase(255,   0,   0,   0, 100, 100,   0,    0,   50, 100,  100) },
+			{ "Lime",    new ColorTestCase(  0, 255,   0, 100,   0, 100,   0,  120,   50, 100,  100) },
+			{ "Blue",    new ColorTestCase(  0,   0, 255, 100, 100,   0,   0,  240,   50, 100,  100) },
+			{ "Yellow",  new ColorTestCase(255, 255,   0,   0,   0, 100,   0,   60,   50, 100,  100) },
+			{ "Cyan",    new ColorTestCase(  0, 255, 255, 100,   0,   0,   0,  180,   50, 100,  100) },
+			{ "Magenta", new ColorTestCase(255,   0, 255,   0, 100,   0,   0,  300,   50, 100,  100) },
+			{ "Maroon",  new ColorTestCase(128,   0,   0,   0, 100, 100,  50,    0, 25.1, 100,   50) },
+			{ "Green",   new ColorTestCase(  0, 128,   0, 100,   0, 100,  50,  120, 25.1, 100,   50) },
+			{ "Navy",    new ColorTestCase(  0,   0, 128, 100, 100,   0,  50,  240, 25.1, 100,   50) },
+			{ "Olive",   new ColorTestCase(128, 128,   0,   0,   0, 100,  50,   60, 25.1, 100,   50) },
+			{ "Purple",  new ColorTestCase(128,   0, 128,   0, 100,   0,  50,  300, 25.1, 100,   50) },
+			{ "Teal",    new ColorTestCase(  0, 128, 128, 100,   0,   0,  50,  180, 25.1, 100,   50) },
 		};
 
 		public static readonly Dictionary<string, ColorTestCase> RGBTestCases = new Dictionary<string, ColorTestCase> {
-			// { name,                                 r    g    b   c%    m%    y%   k%    h°   l%    s%   b%  a}
-			{ "Orange",            new ColorTestCase(255, 164,   0,   0, 35.7,  100,   0, 38.6,  50,  100, 100) },
-			{ "MediumSpringGreen", new ColorTestCase(  0, 250, 154, 100,    0,   38,   2,  157,  49,  100,  98) },
-			{ "Chocolate",         new ColorTestCase(209, 117,  52,   0,   44, 75.1,  18, 24.8,  47, 75.1,  82) },
+			// { name,                                 r    g    b    c%    m%    y%    k%     h°    l%    s%   b%  }
+			{ "Orange",            new ColorTestCase(255, 164,   0,    0, 35.7,  100,    0,  38.6,   50,  100,  100) },
+			{ "MediumSpringGreen", new ColorTestCase(  0, 250, 155,  100,    0,   38,    2, 157.2,   49,  100,   98) },
+			{ "Chocolate",         new ColorTestCase(209, 117,  52,    0,   44, 75.1,   18,  24.8,   51, 75.1,   82) },
+			{ "MoreOrange",        new ColorTestCase(200, 101,  31,    0, 49.5, 84.5, 21.6,  24.9, 45.3, 84.5, 78.4) },
+			{ "Lilac",             new ColorTestCase(101,  31, 255, 60.4, 87.8,    0,    0, 258.8, 56.1, 87.8,  100) },
 		};
 
 		[Test, TestCaseSource (typeof(CommonColorTests), "HueColorFromColorCases")]
@@ -71,6 +73,9 @@ namespace Xamarin.PropertyEditing.Tests
 			foreach (KeyValuePair<string, ColorTestCase> testCaseKVP in PrimaryTestCases) {
 				yield return new TestCaseData (testCaseKVP.Value.CMYK).Returns (testCaseKVP.Value.Color).SetName ("ColorFromCMYK_" + testCaseKVP.Key);
 			}
+			foreach (KeyValuePair<string, ColorTestCase> testCaseKVP in RGBTestCases) {
+				yield return new TestCaseData (testCaseKVP.Value.CMYK).Returns (testCaseKVP.Value.Color).SetName ("ColorFromCMYK_" + testCaseKVP.Key);
+			}
 		}
 
 		[Test, TestCaseSource (typeof (CommonColorTests), "HLSFromColorCases")]
@@ -94,6 +99,10 @@ namespace Xamarin.PropertyEditing.Tests
 			foreach (KeyValuePair<string, ColorTestCase> testCaseKVP in PrimaryTestCases) {
 				yield return new TestCaseData (testCaseKVP.Value.HLS).Returns (testCaseKVP.Value.Color).SetName ("ColorFromHLS_" + testCaseKVP.Key);
 			}
+			// HLS -> RGB conversion is the least reliable, and round-tripping it doesn't quite guarantee accurate enough results that they can be tested for arbitrary colors.
+			//foreach (KeyValuePair<string, ColorTestCase> testCaseKVP in RGBTestCases) {
+			//	yield return new TestCaseData (testCaseKVP.Value.HLS).Returns (testCaseKVP.Value.Color).SetName ("ColorFromHLS_" + testCaseKVP.Key);
+			//}
 		}
 
 		[Test, TestCaseSource (typeof (CommonColorTests), "HLSRoundTripCases")]
@@ -108,6 +117,9 @@ namespace Xamarin.PropertyEditing.Tests
 			foreach (KeyValuePair<string, ColorTestCase> testCaseKVP in PrimaryTestCases) {
 				yield return new TestCaseData (testCaseKVP.Value.HLS).Returns (testCaseKVP.Value.HLS).SetName ("HLSRoundTrip_" + testCaseKVP.Key);
 			}
+			foreach (KeyValuePair<string, ColorTestCase> testCaseKVP in RGBTestCases) {
+				yield return new TestCaseData (testCaseKVP.Value.HLS).Returns (testCaseKVP.Value.HLS).SetName ("HLSRoundTrip_" + testCaseKVP.Key);
+			}
 		}
 
 		[Test, TestCaseSource (typeof (CommonColorTests), "HSBFromColorCases")]
@@ -131,6 +143,9 @@ namespace Xamarin.PropertyEditing.Tests
 			foreach (KeyValuePair<string, ColorTestCase> testCaseKVP in PrimaryTestCases) {
 				yield return new TestCaseData (testCaseKVP.Value.HSB).Returns (testCaseKVP.Value.Color).SetName ("ColorFromHSB_" + testCaseKVP.Key);
 			}
+			foreach (KeyValuePair<string, ColorTestCase> testCaseKVP in RGBTestCases) {
+				yield return new TestCaseData (testCaseKVP.Value.HSB).Returns (testCaseKVP.Value.Color).SetName ("ColorFromHSB_" + testCaseKVP.Key);
+			}
 		}
 
 		[Test, TestCaseSource (typeof (CommonColorTests), "HSBRoundTripCases")]
@@ -145,6 +160,9 @@ namespace Xamarin.PropertyEditing.Tests
 			foreach (KeyValuePair<string, ColorTestCase> testCaseKVP in PrimaryTestCases) {
 				yield return new TestCaseData (testCaseKVP.Value.HSB).Returns (testCaseKVP.Value.HSB).SetName ("HSBRoundTrip_" + testCaseKVP.Key);
 			}
+			foreach (KeyValuePair<string, ColorTestCase> testCaseKVP in RGBTestCases) {
+				yield return new TestCaseData (testCaseKVP.Value.HSB).Returns (testCaseKVP.Value.HSB).SetName ("HSBRoundTrip_" + testCaseKVP.Key);
+			}
 		}
 
 		[Test]
@@ -189,10 +207,10 @@ namespace Xamarin.PropertyEditing.Tests
 			public override bool Equals (object obj)
 			{
 				var other = (CMYK)obj;
-				return Math.Round (other.C - C, 2) == 0
-					&& Math.Round (other.M - M, 2) == 0
-					&& Math.Round (other.Y - Y, 2) == 0
-					&& Math.Round (other.K - K, 2) == 0;
+				return Math.Round (other.C, 2) == Math.Round(C, 2)
+					&& Math.Round (other.M, 2) == Math.Round (M, 2)
+					&& Math.Round (other.Y, 2) == Math.Round (Y, 2)
+					&& Math.Round (other.K, 2) == Math.Round (K, 2);
 			}
 
 			public override string ToString () => $"{{ C:{C:P1}, M:{M:P1}, Y:{Y:P1}, K:{K:P1} }}";
@@ -214,9 +232,9 @@ namespace Xamarin.PropertyEditing.Tests
 			public override bool Equals (object obj)
 			{
 				var other = (HLS)obj;
-				return Math.Round (other.Hue - Hue, 1) == 0
-					&& Math.Round (other.Lightness - Lightness, 1) == 0
-					&& Math.Round (other.Saturation - Saturation, 1) == 0;
+				return Math.Round (other.Hue, 1) == Math.Round(Hue, 1)
+					&& Math.Round (other.Lightness, 1) == Math.Round(Lightness, 1)
+					&& Math.Round (other.Saturation, 1) == Math.Round(Saturation, 1);
 			}
 
 			public override string ToString () => $"{{ H:{Hue:F1}°, S:{Saturation:P1}, L:{Lightness:P1} }}";
@@ -238,9 +256,9 @@ namespace Xamarin.PropertyEditing.Tests
 			public override bool Equals (object obj)
 			{
 				var other = (HSB)obj;
-				return Math.Round (other.Hue - Hue, 1) == 0
-					&& Math.Round (other.Saturation - Saturation, 1) == 0
-					&& Math.Round (other.Brightness - Brightness, 1) == 0;
+				return Math.Round (other.Hue, 1) == Math.Round(Hue, 1)
+					&& Math.Round (other.Saturation, 1) == Math.Round(Saturation, 1)
+					&& Math.Round (other.Brightness, 1) == Math.Round(Brightness, 1);
 			}
 
 			public override string ToString () => $"{{ H:{Hue:F1}°, S:{Saturation:P1}, B:{Brightness:P1} }}";