public static void TestColorMath()
{
AssertEqualRgb("[1, 0, 0]", ColorMath.RgbToHsv(1, 0, 0));
AssertEqualRgb("[0, 1, 0]", ColorMath.RgbToHsv(0, 1, 0));
AssertEqualRgb("[0, 0, 1]", ColorMath.RgbToHsv(0, 0, 1));
Assert.Equal(0, ColorMath.CalcBrightness(0, 0, 0));
Assert.Equal(0.9278, ColorMath.CalcBrightness(1, 1, 0)); // Yellow is bright
Assert.Equal(1, ColorMath.CalcBrightness(1, 1, 1));
var whiteBrightnes = ColorMath.CalcBrightness(1, 1, 1);
var blueBrightness = ColorMath.CalcBrightness(0, 0, 1);
Assert.Equal(1, whiteBrightnes);
Assert.Equal(0.0722, blueBrightness); // Blue is dark
// Blue on white has a great contrast (is well readable):
Assert.True(8 < ColorMath.CalcContrastRatio(whiteBrightnes, blueBrightness));
var green = ColorMath.RgbToHsv(0, 1, 0);
Assert.Equal("[0,3333333, 1, 1]", green.ToStringV2(c => "" + c));
ColorMath.InvertHue(green); // Green becomes purple
Assert.Equal("[0,8333333, 1, 1]", green.ToStringV2(c => "" + c));
AssertEqualRgb("[1, 0, 1]", green); // Purple is red + blue
}
public static bool HasGoodContrastTo(this Color self, Color otherColor)
{
return(ColorMath.CalcContrastRatio(self.GetBrightness(), otherColor.GetBrightness()) > 4.5);
}
