HSL To RGB

This algorithm converts HSL color model to RGB color model.

• C#
• VB.Net
• C
• C++
• PHP

									public struct RGB
{
	private byte _r;
	private byte _g;
	private byte _b;

	public RGB(byte r, byte g, byte b)
	{
		this._r = r;
		this._g = g;
		this._b = b;
	}

	public byte R
	{
		get { return this._r; }
		set { this._r = value; }
	}

	public byte G
	{
		get { return this._g; }
		set { this._g = value; }
	}

	public byte B
	{
		get { return this._b; }
		set { this._b = value; }
	}

	public bool Equals(RGB rgb)
	{
		return (this.R == rgb.R) && (this.G == rgb.G) && (this.B == rgb.B);
	}
}

public struct HSL
{
	private int _h;
	private float _s;
	private float _l;

	public HSL(int h, float s, float l)
	{
		this._h = h;
		this._s = s;
		this._l = l;
	}

	public int H
	{
		get { return this._h; }
		set { this._h = value; }
	}

	public float S
	{
		get { return this._s; }
		set { this._s = value; }
	}

	public float L
	{
		get { return this._l; }
		set { this._l = value; }
	}

	public bool Equals(HSL hsl)
	{
		return (this.H == hsl.H) && (this.S == hsl.S) && (this.L == hsl.L);
	}
}

public static RGB HSLToRGB(HSL hsl)
{
	byte r = 0;
	byte g = 0;
	byte b = 0;

	if (hsl.S == 0)
	{
		r = g = b = (byte)(hsl.L * 255);
	}
	else
	{
		float v1, v2;
		float hue = (float)hsl.H / 360;

		v2 = (hsl.L < 0.5) ? (hsl.L * (1 + hsl.S)) : ((hsl.L + hsl.S) - (hsl.L * hsl.S));
		v1 = 2 * hsl.L - v2;

		r = (byte)(255 * HueToRGB(v1, v2, hue + (1.0f / 3)));
		g = (byte)(255 * HueToRGB(v1, v2, hue));
		b = (byte)(255 * HueToRGB(v1, v2, hue - (1.0f / 3)));
	}

	return new RGB(r, g, b);
}

private static float HueToRGB(float v1, float v2, float vH)
{
	if (vH < 0)
		vH += 1;

	if (vH > 1)
		vH -= 1;

	if ((6 * vH) < 1)
		return (v1 + (v2 - v1) * 6 * vH);

	if ((2 * vH) < 1)
		return v2;

	if ((3 * vH) < 2)
		return (v1 + (v2 - v1) * ((2.0f / 3) - vH) * 6);

	return v1;
}
								

Example

									HSL data = new HSL(138, 0.50f, 0.76f);
RGB value = HSLToRGB(data);
								

Output

									R: 163
G: 224
B: 181