    /// Hue: 0 .. 360
    /// Saturation: 0.0 .. 1.0
    /// Luminosity: 0.0 .. 1.0
    /// Alpha: 0 .. 255
    /// </remarks>
    public class perHsla
    {
        public perHsla(float hue, float saturation, float luminosity) : this(hue, saturation, luminosity, 255)
        {
        }

        public perHsla(float hue, float saturation, float luminosity, byte alpha)
        {