private static Dictionary <string, HtmlColor> InitKnownColors()
{
var colors = new Dictionary <string, HtmlColor>(StringComparer.OrdinalIgnoreCase)
{
{ "Black", HtmlColor.Black },
{ "White", HtmlColor.FromArgb(255, 255, 255) },
{ "AliceBlue", HtmlColor.FromArgb(240, 248, 255) },
{ "LightSalmon", HtmlColor.FromArgb(255, 160, 122) },
{ "AntiqueWhite", HtmlColor.FromArgb(250, 235, 215) },
{ "LightSeaGreen", HtmlColor.FromArgb(32, 178, 170) },
{ "Aqua", HtmlColor.FromArgb(0, 255, 255) },
{ "LightSkyBlue", HtmlColor.FromArgb(135, 206, 250) },
{ "Aquamarine", HtmlColor.FromArgb(127, 255, 212) },
{ "LightSlateGray", HtmlColor.FromArgb(119, 136, 153) },
{ "Azure", HtmlColor.FromArgb(240, 255, 255) },
{ "LightSteelBlue", HtmlColor.FromArgb(176, 196, 222) },
{ "Beige", HtmlColor.FromArgb(245, 245, 220) },
{ "LightYellow", HtmlColor.FromArgb(255, 255, 224) },
{ "Bisque", HtmlColor.FromArgb(255, 228, 196) },
{ "Lime", HtmlColor.FromArgb(0, 255, 0) },
{ "LimeGreen", HtmlColor.FromArgb(50, 205, 50) },
{ "BlanchedAlmond", HtmlColor.FromArgb(255, 255, 205) },
{ "Linen", HtmlColor.FromArgb(250, 240, 230) },
{ "Blue", HtmlColor.FromArgb(0, 0, 255) },
{ "Magenta", HtmlColor.FromArgb(255, 0, 255) },
{ "BlueViolet", HtmlColor.FromArgb(138, 43, 226) },
{ "Maroon", HtmlColor.FromArgb(128, 0, 0) },
{ "Brown", HtmlColor.FromArgb(165, 42, 42) },
{ "MediumAquamarine", HtmlColor.FromArgb(102, 205, 170) },
{ "BurlyWood", HtmlColor.FromArgb(222, 184, 135) },
{ "MediumBlue", HtmlColor.FromArgb(0, 0, 205) },
{ "CadetBlue", HtmlColor.FromArgb(95, 158, 160) },
{ "MediumOrchid", HtmlColor.FromArgb(186, 85, 211) },
{ "Chartreuse", HtmlColor.FromArgb(127, 255, 0) },
{ "MediumPurple", HtmlColor.FromArgb(147, 112, 219) },
{ "Chocolate", HtmlColor.FromArgb(210, 105, 30) },
{ "MediumSeaGreen", HtmlColor.FromArgb(60, 179, 113) },
{ "Coral", HtmlColor.FromArgb(255, 127, 80) },
{ "MediumSlateBlue", HtmlColor.FromArgb(123, 104, 238) },
{ "CornflowerBlue", HtmlColor.FromArgb(100, 149, 237) },
{ "MediumSpringGreen", HtmlColor.FromArgb(0, 250, 154) },
{ "Cornsilk", HtmlColor.FromArgb(255, 248, 220) },
{ "MediumTurquoise", HtmlColor.FromArgb(72, 209, 204) },
{ "Crimson", HtmlColor.FromArgb(220, 20, 60) },
{ "MediumVioletRed", HtmlColor.FromArgb(199, 21, 112) },
{ "Cyan", HtmlColor.FromArgb(0, 255, 255) },
{ "MidnightBlue", HtmlColor.FromArgb(25, 25, 112) },
{ "DarkBlue", HtmlColor.FromArgb(0, 0, 139) },
{ "MintCream", HtmlColor.FromArgb(245, 255, 250) },
{ "DarkCyan", HtmlColor.FromArgb(0, 139, 139) },
{ "MistyRose", HtmlColor.FromArgb(255, 228, 225) },
{ "DarkGoldenrod", HtmlColor.FromArgb(184, 134, 11) },
{ "Moccasin", HtmlColor.FromArgb(255, 228, 181) },
{ "DarkGray", HtmlColor.FromArgb(169, 169, 169) },
{ "NavajoWhite", HtmlColor.FromArgb(255, 222, 173) },
{ "DarkGreen", HtmlColor.FromArgb(0, 100, 0) },
{ "Navy", HtmlColor.FromArgb(0, 0, 128) },
{ "DarkKhaki", HtmlColor.FromArgb(189, 183, 107) },
{ "OldLace", HtmlColor.FromArgb(253, 245, 230) },
{ "DarkMagena", HtmlColor.FromArgb(139, 0, 139) },
{ "Olive", HtmlColor.FromArgb(128, 128, 0) },
{ "DarkOliveGreen", HtmlColor.FromArgb(85, 107, 47) },
{ "OliveDrab", HtmlColor.FromArgb(107, 142, 45) },
{ "DarkOrange", HtmlColor.FromArgb(255, 140, 0) },
{ "Orange", HtmlColor.FromArgb(255, 165, 0) },
{ "DarkOrchid", HtmlColor.FromArgb(153, 50, 204) },
{ "OrangeRed", HtmlColor.FromArgb(255, 69, 0) },
{ "DarkRed", HtmlColor.FromArgb(139, 0, 0) },
{ "Orchid", HtmlColor.FromArgb(218, 112, 214) },
{ "DarkSalmon", HtmlColor.FromArgb(233, 150, 122) },
{ "PaleGoldenrod", HtmlColor.FromArgb(238, 232, 170) },
{ "DarkSeaGreen", HtmlColor.FromArgb(143, 188, 143) },
{ "PaleGreen", HtmlColor.FromArgb(152, 251, 152) },
{ "DarkSlateBlue", HtmlColor.FromArgb(72, 61, 139) },
{ "PaleTurquoise", HtmlColor.FromArgb(175, 238, 238) },
{ "DarkSlateGray", HtmlColor.FromArgb(40, 79, 79) },
{ "PaleVioletRed", HtmlColor.FromArgb(219, 112, 147) },
{ "DarkTurquoise", HtmlColor.FromArgb(0, 206, 209) },
{ "PapayaWhip", HtmlColor.FromArgb(255, 239, 213) },
{ "DarkViolet", HtmlColor.FromArgb(148, 0, 211) },
{ "PeachPuff", HtmlColor.FromArgb(255, 218, 155) },
{ "DeepPink", HtmlColor.FromArgb(255, 20, 147) },
{ "Peru", HtmlColor.FromArgb(205, 133, 63) },
{ "DeepSkyBlue", HtmlColor.FromArgb(0, 191, 255) },
{ "Pink", HtmlColor.FromArgb(255, 192, 203) },
{ "DimGray", HtmlColor.FromArgb(105, 105, 105) },
{ "Plum", HtmlColor.FromArgb(221, 160, 221) },
{ "DodgerBlue", HtmlColor.FromArgb(30, 144, 255) },
{ "PowderBlue", HtmlColor.FromArgb(176, 224, 230) },
{ "Firebrick", HtmlColor.FromArgb(178, 34, 34) },
{ "Purple", HtmlColor.FromArgb(128, 0, 128) },
{ "FloralWhite", HtmlColor.FromArgb(255, 250, 240) },
{ "Red", HtmlColor.FromArgb(255, 0, 0) },
{ "ForestGreen", HtmlColor.FromArgb(34, 139, 34) },
{ "RosyBrown", HtmlColor.FromArgb(188, 143, 143) },
{ "Fuschia", HtmlColor.FromArgb(255, 0, 255) },
{ "RoyalBlue", HtmlColor.FromArgb(65, 105, 225) },
{ "Gainsboro", HtmlColor.FromArgb(220, 220, 220) },
{ "SaddleBrown", HtmlColor.FromArgb(139, 69, 19) },
{ "GhostWhite", HtmlColor.FromArgb(248, 248, 255) },
{ "Salmon", HtmlColor.FromArgb(250, 128, 114) },
{ "Gold", HtmlColor.FromArgb(255, 215, 0) },
{ "SandyBrown", HtmlColor.FromArgb(244, 164, 96) },
{ "Goldenrod", HtmlColor.FromArgb(218, 165, 32) },
{ "SeaGreen", HtmlColor.FromArgb(46, 139, 87) },
{ "Gray", HtmlColor.FromArgb(128, 128, 128) },
{ "Seashell", HtmlColor.FromArgb(255, 245, 238) },
{ "Green", HtmlColor.FromArgb(0, 128, 0) },
{ "Sienna", HtmlColor.FromArgb(160, 82, 45) },
{ "GreenYellow", HtmlColor.FromArgb(173, 255, 47) },
{ "Silver", HtmlColor.FromArgb(192, 192, 192) },
{ "Honeydew", HtmlColor.FromArgb(240, 255, 240) },
{ "SkyBlue", HtmlColor.FromArgb(135, 206, 235) },
{ "HotPink", HtmlColor.FromArgb(255, 105, 180) },
{ "SlateBlue", HtmlColor.FromArgb(106, 90, 205) },
{ "IndianRed", HtmlColor.FromArgb(205, 92, 92) },
{ "SlateGray", HtmlColor.FromArgb(112, 128, 144) },
{ "Indigo", HtmlColor.FromArgb(75, 0, 130) },
{ "Snow", HtmlColor.FromArgb(255, 250, 250) },
{ "Ivory", HtmlColor.FromArgb(255, 240, 240) },
{ "SpringGreen", HtmlColor.FromArgb(0, 255, 127) },
{ "Khaki", HtmlColor.FromArgb(240, 230, 140) },
{ "SteelBlue", HtmlColor.FromArgb(70, 130, 180) },
{ "Lavender", HtmlColor.FromArgb(230, 230, 250) },
{ "Tan", HtmlColor.FromArgb(210, 180, 140) },
{ "LavenderBlush", HtmlColor.FromArgb(255, 240, 245) },
{ "Teal", HtmlColor.FromArgb(0, 128, 128) },
{ "LawnGreen", HtmlColor.FromArgb(124, 252, 0) },
{ "Thistle", HtmlColor.FromArgb(216, 191, 216) },
{ "LemonChiffon", HtmlColor.FromArgb(255, 250, 205) },
{ "Tomato", HtmlColor.FromArgb(253, 99, 71) },
{ "LightBlue", HtmlColor.FromArgb(173, 216, 230) },
{ "Turquoise", HtmlColor.FromArgb(64, 224, 208) },
{ "LightCoral", HtmlColor.FromArgb(240, 128, 128) },
{ "Violet", HtmlColor.FromArgb(238, 130, 238) },
{ "LightCyan", HtmlColor.FromArgb(224, 255, 255) },
{ "Wheat", HtmlColor.FromArgb(245, 222, 179) },
{ "LightGoldenrodYellow", HtmlColor.FromArgb(250, 250, 210) },
{ "LightGreen", HtmlColor.FromArgb(144, 238, 144) },
{ "WhiteSmoke", HtmlColor.FromArgb(245, 245, 245) },
{ "LightGray", HtmlColor.FromArgb(211, 211, 211) },
{ "Yellow", HtmlColor.FromArgb(255, 255, 0) },
{ "LightPink", HtmlColor.FromArgb(255, 182, 193) },
{ "YellowGreen", HtmlColor.FromArgb(154, 205, 50) },
{ "Transparent", HtmlColor.FromArgb(0, 0, 0, 0) }
};
return(colors);
}
/// <summary>
/// Convert a color using the HSL to RGB.
/// </summary>
/// <param name="alpha">The alpha component (0.0-1.0).</param>
/// <param name="hue">The Hue component (0.0 - 360.0).</param>
/// <param name="saturation">The saturation component (0.0 - 1.0).</param>
/// <param name="luminosity">The luminosity component (0.0 - 1.0).</param>
public static HtmlColor FromHsl(double alpha, double hue, double saturation, double luminosity)
{
if (alpha < 0.0 || alpha > 1.0)
{
throw new ArgumentOutOfRangeException(nameof(alpha), alpha, "Alpha should be comprised between 0.0 and 1.0");
}
if (hue < 0 || hue > 360)
{
throw new ArgumentOutOfRangeException(nameof(hue), hue, "Hue should be comprised between 0° and 360°");
}
if (saturation < 0 || saturation > 1)
{
throw new ArgumentOutOfRangeException(nameof(saturation), saturation, "Saturation should be comprised between 0.0 and 1.0");
}
if (luminosity < 0 || luminosity > 1)
{
throw new ArgumentOutOfRangeException(nameof(luminosity), luminosity, "Brightness should be comprised between 0.0 and 1.0");
}
if (0 == saturation)
{
return(HtmlColor.FromArgb(alpha, Convert.ToByte(luminosity * 255),
Convert.ToByte(luminosity * 255), Convert.ToByte(luminosity * 255)));
}
double fMax, fMid, fMin;
int iSextant;
if (0.5 < luminosity)
{
fMax = luminosity - (luminosity * saturation) + saturation;
fMin = luminosity + (luminosity * saturation) - saturation;
}
else
{
fMax = luminosity + (luminosity * saturation);
fMin = luminosity - (luminosity * saturation);
}
iSextant = (int)Math.Floor(hue / 60f);
if (300f <= hue)
{
hue -= 360f;
}
hue /= 60f;
hue -= 2f * (float)Math.Floor(((iSextant + 1f) % 6f) / 2f);
if (0 == iSextant % 2)
{
fMid = hue * (fMax - fMin) + fMin;
}
else
{
fMid = fMin - hue * (fMax - fMin);
}
byte iMax = Convert.ToByte(fMax * 255);
byte iMid = Convert.ToByte(fMid * 255);
byte iMin = Convert.ToByte(fMin * 255);
switch (iSextant)
{
case 1:
return(HtmlColor.FromArgb(alpha, iMid, iMax, iMin));
case 2:
return(HtmlColor.FromArgb(alpha, iMin, iMax, iMid));
case 3:
return(HtmlColor.FromArgb(alpha, iMin, iMid, iMax));
case 4:
return(HtmlColor.FromArgb(alpha, iMid, iMin, iMax));
case 5:
return(HtmlColor.FromArgb(alpha, iMax, iMin, iMid));
default:
return(HtmlColor.FromArgb(alpha, iMax, iMid, iMin));
}
}