/// <summary>
/// Gets the number of color properties for the current <see cref="ColorSpace"/> instance
/// </summary>
/// <param name="color">The <see cref="ColorSpace"/> object</param>
/// <returns>The number of color properties for the current instance</returns>
public static int GetPropertyCount(ColorSpace color)
{
return((int)color.GetType().GetField("PropertyCount").GetValue(color));
}
private static Rgb NormalizeRgb(ColorSpace colorSpace)
{
var rgb = colorSpace.ToRgb();
if (rgb.R < 0 || rgb.R.ApproximatelyEquals(0, 0.001))
{
rgb.R = 0;
}
else if (rgb.R > 255 || rgb.R.ApproximatelyEquals(255, 0.001))
{
rgb.R = 255;
}
else
{
rgb.R = System.Math.Round(rgb.R);
}
if (rgb.G < 0 || rgb.G.ApproximatelyEquals(0, 0.001))
{
rgb.G = 0;
}
else if (rgb.G > 255 || rgb.G.ApproximatelyEquals(255, 0.001))
{
rgb.G = 255;
}
else
{
rgb.G = System.Math.Round(rgb.G);
}
if (rgb.B < 0 || rgb.B.ApproximatelyEquals(0, 0.001))
{
rgb.B = 0;
}
else if (rgb.B > 255 || rgb.B.ApproximatelyEquals(255, 0.001))
{
rgb.B = 255;
}
else
{
rgb.B = System.Math.Round(rgb.B);
}
var rgba = rgb as Rgba;
if (rgba != null)
{
if (rgba.A < 0 || rgba.A.ApproximatelyEquals(0, 0.001))
{
rgba.A = 0;
}
else if (rgba.A > 255 || rgba.A.ApproximatelyEquals(255, 0.001))
{
rgba.A = 255;
}
else
{
rgba.A = System.Math.Round(rgba.A);
}
}
return(rgb);
}
private static double CompareCie2000(ColorSpace color1, ColorSpace color2)
{
const double kl = 1.0;
const double kc = 1.0;
const double kh = 1.0;
var lab1 = color1.ToColorSpace <Lab>();
var lab2 = color2.ToColorSpace <Lab>();
var lBar = (lab1.L + lab2.L) / 2.0;
var c1 = System.Math.Sqrt(lab1.A * lab1.A + lab1.B * lab1.B);
var c2 = System.Math.Sqrt(lab2.A * lab2.A + lab2.B * lab2.B);
var cBar = (c1 + c2) / 2.0;
var cBarInPower7 = cBar * cBar * cBar;
cBarInPower7 *= cBarInPower7 * cBar;
var g = 1 - System.Math.Sqrt(cBarInPower7 / (cBarInPower7 + 6103515625));
var aPrime1 = lab1.A + lab1.A / 2.0 * g;
var aPrime2 = lab2.A + lab2.A / 2.0 * g;
var cPrime1 = System.Math.Sqrt(aPrime1 * aPrime1 + lab1.B * lab1.B);
var cPrime2 = System.Math.Sqrt(aPrime2 * aPrime2 + lab2.B * lab2.B);
var cBarPrime = (cPrime1 + cPrime2) / 2.0;
var hPrime1 = System.Math.Atan2(lab1.B, aPrime1) % 360;
var hPrime2 = System.Math.Atan2(lab2.B, aPrime2) % 360;
var hBar = System.Math.Abs(hPrime1 - hPrime2);
double deltaHPrime;
if (hBar <= 180)
{
deltaHPrime = hPrime2 - hPrime1;
}
else if (hBar > 180 && hPrime2 <= hPrime1)
{
deltaHPrime = hPrime2 - hPrime1 + 360.0;
}
else
{
deltaHPrime = hPrime2 - hPrime1 - 360.0;
}
var deltaLPrime = lab2.L - lab1.L;
var deltaCPrime = cPrime2 - cPrime1;
deltaHPrime = 2 * System.Math.Sqrt(cPrime1 * cPrime2) * System.Math.Sin(deltaHPrime / 2.0);
var hBarPrime = hBar > 180 ? (hPrime1 + hPrime2 + 360) / 2.0 : (hPrime1 + hPrime2) / 2.0;
var t = 1 - .17 * System.Math.Cos(hBarPrime - 30) + .24 * System.Math.Cos(2 * hBarPrime) +
.32 * System.Math.Cos(3 * hBarPrime + 6) - .2 * System.Math.Cos(4 * hBarPrime - 63);
var lBarMinus50Sqr = (lBar - 50) * (lBar - 50);
var sl = 1 + .015 * lBarMinus50Sqr / System.Math.Sqrt(20 + lBarMinus50Sqr);
var sc = 1 + .045 * cBarPrime;
var sh = 1 + .015 * cBarPrime * t;
var cBarPrimeInPower7 = cBarPrime * cBarPrime * cBarPrime;
cBarPrimeInPower7 *= cBarPrimeInPower7 * cBarPrime;
var rt = -2 * System.Math.Sqrt(cBarPrimeInPower7 / (cBarPrimeInPower7 + 6103515625)) // 25 ^ 7
* System.Math.Sin(60.0 * System.Math.Exp(-((hBarPrime - 275.0) / 25.0)));
var deltaLPrimeDivklsl = deltaLPrime / (kl * sl);
var deltaCPrimeDivkcsc = deltaCPrime / (kc * sc);
var deltaHPrimeDivkhsh = deltaHPrime / (kh * sh);
var deltaE = System.Math.Sqrt(
deltaLPrimeDivklsl * deltaLPrimeDivklsl + deltaCPrimeDivkcsc * deltaCPrimeDivkcsc +
deltaHPrimeDivkhsh * deltaHPrimeDivkhsh + rt * (deltaCPrime / (kc * kh)) * (deltaHPrime / (kh * sh)));
return(deltaE);
}
/// <summary>
/// Gets the "Friendly Name" of the current <see cref="ColorSpace"/> instance
/// </summary>
/// <param name="color">The <see cref="ColorSpace"/> object</param>
/// <returns>Friendly name string</returns>
public static string GetFriendlyName(ColorSpace color)
{
return(color.GetType().GetField("FriendlyName").GetValue(color) as string);
}
/// <summary>
/// Calculates the ΔE of this color compared to another color, using the specified comparison method.
/// This value represents the perceptual difference between the two colors.
/// </summary>
/// <param name="other">The color to compare to this color</param>
/// <param name="method">
/// The algorith to use for the comparison.
/// There is an efficiency/accuracy trade-off between the different methods.
/// </param>
/// <returns>
/// ΔE value representing the perceived difference between this color and the comparison color.
/// </returns>
public double Compare(ColorSpace other, ComparisonMethod method = ComparisonMethod.Cie2000)
{
return(Compare(this, other, method));
}
/// <summary>
/// Determines if two colors are "close enough" to be perceived as the same color.
/// </summary>
/// <param name="other">A color to compare to this instance.</param>
/// <returns>
/// true if this color and the comparison color can be perceived as the same.
/// false if this color and the comparison color appear different to the human eye.
/// </returns>
public bool PerceptuallyEquals(ColorSpace other)
{
return(Compare(this, other) < JustNoticeableDifference);
}
/// <summary>
/// Gets basic color chords based on the current (dominant) color.
/// Useful for creating color schemes.
/// </summary>
/// <param name="harmony">The type of color chord to create.</param>
/// <param name="includeThisColor">
/// If true, the current color will be included in the resulting ColorSpace array.
/// </param>
/// <returns>An array of ColorSpace objects that make up the specified color chord.</returns>
public ColorSpace[] GetHarmony(ColorHarmony harmony, bool includeThisColor = false)
{
var resultSizeOffset = includeThisColor ? 1 : 0;
ColorSpace[] result;
switch (harmony)
{
case ColorHarmony.Complementary:
{
var i = 0;
result = new ColorSpace[1 + resultSizeOffset];
var hsl = ToColorSpace <Hsl>();
hsl.H = AddDegrees(hsl.H, 180);
if (includeThisColor)
{
result[i++] = this;
}
result[i] = hsl;
break;
}
case ColorHarmony.SplitComplementary:
{
var i = 0;
result = new ColorSpace[2 + resultSizeOffset];
var hsl1 = ToColorSpace <Hsl>();
var hsl2 = ToColorSpace <Hsl>();
hsl1.H = AddDegrees(hsl1.H, 150);
hsl2.H = SubtractDegrees(hsl2.H, 150);
if (includeThisColor)
{
result[i++] = this;
}
result[i++] = hsl1;
result[i] = hsl2;
break;
}
case ColorHarmony.Analogous:
{
var i = 0;
result = new ColorSpace[2 + resultSizeOffset];
var hsl1 = ToColorSpace <Hsl>();
var hsl2 = ToColorSpace <Hsl>();
hsl1.H = AddDegrees(hsl1.H, 30);
hsl2.H = SubtractDegrees(hsl2.H, 30);
if (includeThisColor)
{
result[i++] = this;
}
result[i++] = hsl1;
result[i] = hsl2;
break;
}
case ColorHarmony.Triadic:
{
var i = 0;
result = new ColorSpace[2 + resultSizeOffset];
var hsl1 = ToColorSpace <Hsl>();
var hsl2 = ToColorSpace <Hsl>();
hsl1.H = AddDegrees(hsl1.H, 120);
hsl2.H = SubtractDegrees(hsl2.H, 120);
if (includeThisColor)
{
result[i++] = this;
}
result[i++] = hsl1;
result[i] = hsl2;
break;
}
case ColorHarmony.Tetradic:
{
var i = 0;
result = new ColorSpace[3 + resultSizeOffset];
var hsl1 = ToColorSpace <Hsl>();
hsl1.H = AddDegrees(hsl1.H, 30);
var hsl2And3 = GetHarmony(ColorHarmony.SplitComplementary);
if (includeThisColor)
{
result[i++] = this;
}
result[i++] = hsl1;
result[i++] = hsl2And3[0];
result[i] = hsl2And3[1];
break;
}
case ColorHarmony.Square:
{
var i = 0;
result = new ColorSpace[3 + resultSizeOffset];
var hsl1 = ToColorSpace <Hsl>();
var hsl2 = ToColorSpace <Hsl>();
var hsl3 = ToColorSpace <Hsl>();
hsl1.H = AddDegrees(hsl1.H, 90);
hsl2.H = AddDegrees(hsl2.H, 180);
hsl3.H = AddDegrees(hsl3.H, 270);
if (includeThisColor)
{
result[i++] = this;
}
result[i++] = hsl1;
result[i++] = hsl2;
result[i] = hsl3;
break;
}
default:
throw new ArgumentException("Unrecognized color harmony", nameof(harmony));
}
return(result);
}
public abstract bool VirtuallyEquals(ColorSpace other);
public abstract bool Equals(ColorSpace other);
