/// <summary>
/// 指定したHslColorからColorを作成する
/// </summary>
/// <param name="hsl">HslColor</param>
/// <returns>Color</returns>
public static Color ToRgb(HslColor hsl)
{
float s = hsl.S;
float l = hsl.L;
float r1, g1, b1;
if (s == 0)
{
r1 = l;
g1 = l;
b1 = l;
}
else
{
float h = hsl.H / 60f;
int i = (int)Math.Floor(h);
float f = h - i;
//float c = (1f - Math.Abs(2f * l - 1f)) * s;
float c;
if (l < 0.5f)
{
c = 2f * s * l;
}
else
{
c = 2f * s * (1f - l);
}
float m = l - c / 2f;
float p = c + m;
//float x = c * (1f - Math.Abs(h % 2f - 1f));
float q; // q = x + m
if (i % 2 == 0)
{
q = l + c * (f - 0.5f);
}
else
{
q = l - c * (f - 0.5f);
}
switch (i)
{
case 0:
r1 = p;
g1 = q;
b1 = m;
break;
case 1:
r1 = q;
g1 = p;
b1 = m;
break;
case 2:
r1 = m;
g1 = p;
b1 = q;
break;
case 3:
r1 = m;
g1 = q;
b1 = p;
break;
case 4:
r1 = q;
g1 = m;
b1 = p;
break;
case 5:
r1 = p;
g1 = m;
b1 = q;
break;
default:
throw new ArgumentException("色相の値が不正です。", "hsl");
}
}
return(Color.FromArgb(
(int)Math.Round(r1 * 255f),
(int)Math.Round(g1 * 255f),
(int)Math.Round(b1 * 255f)));
}
