private static double ComputeH(RgbType rgb, double cmax, double delta)
{
double hue;
if (delta == 0)
{
hue = 0;
}
else if (cmax == rgb.Red)
{
hue = ((rgb.Green - rgb.Blue) / delta) % 6;
}
else if (cmax == rgb.Green)
{
hue = ((rgb.Blue - rgb.Red) / delta) + 2;
}
else
{
hue = ((rgb.Red - rgb.Green) / delta) + 4;
}
hue = Math.Round(hue * 60);
if (hue < 0)
{
hue += 360;
}
return(hue);
}
private static RgbType HexToRgb(this string hexIn, double opacity)
{
string hex = hexIn.Trim();
var rgb = new RgbType();
var regex = new Regex("^#?(([0-9a-zA-Z]{3}){1,3})$");
Match match = regex.Match(hex);
if (match != null)
{
rgb.Opacity = opacity;
hex = match.Value.Trim('#');
if (hex.Length == 6)
{
rgb.Red = Convert.ToInt32(hex.Substring(0, 2), 16);
rgb.Green = Convert.ToInt32(hex.Substring(2, 2), 16);
rgb.Blue = Convert.ToInt32(hex.Substring(4, 2), 16);
}
else if (hex.Length == 3)
{
rgb.Red = Convert.ToInt32(hex.Substring(0, 1) + hex.Substring(0, 1), 16);
rgb.Green = Convert.ToInt32(hex.Substring(1, 1) + hex.Substring(1, 1), 16);
rgb.Blue = Convert.ToInt32(hex.Substring(2, 1) + hex.Substring(2, 1), 16);
}
}
return(rgb);
}
private static HslType HexToHsl(this string hexIn)
{
/*
* the source text is taken from here (with minor modifications):
* https://css-tricks.com/converting-color-spaces-in-javascript/
*/
// Convert hex to RGB first. Ignore opacity
RgbType rgb = hexIn.HexToRgb(1);
// Then to HSL
rgb.ToHsl();
var cmin = rgb.Min();
var cmax = rgb.Max();
var delta = cmax - cmin;
var hls = new HslType
{
Hue = ComputeH(rgb, cmax, delta),
Lightness = (cmax + cmin) / 2
};
hls.Saturation = delta == 0 ? 0 : delta / (1 - Math.Abs(2 * hls.Lightness - 1));
hls.Saturation = Convert.ToDouble(String.Format("{0:0.0}", hls.Saturation * 100));
hls.Lightness = Convert.ToDouble(String.Format("{0:0.0}", hls.Lightness * 100));
hls.Round();
return(hls);
}
