diff --git a/colours.c b/colours.c
index bf5ee31..dabb8e2 100644
--- a/colours.c
+++ b/colours.c
@@ -1,188 +1,327 @@
-#include "colours.h"
-
-#include <tgmath.h>
-
-struct ColourRGB CMYKtoRGB(struct ColourCMYK cmyk)
-{
-	struct ColourRGB result;
-
-	result.r = (1.0 - cmyk.c) * (1.0 - cmyk.k);
-	result.g = (1.0 - cmyk.m) * (1.0 - cmyk.k);
-	result.b = (1.0 - cmyk.y) * (1.0 - cmyk.k);
-
-	return result;
-}
-
-struct ColourRGB HSVtoRGB(struct ColourHSV hsv)
-{
-	struct ColourRGB result;
-	double c;
-	double x;
-	double m;
-
-	c = hsv.s * hsv.v;
-	x = c * (1 - fabs(fmod(hsv.h / 60.0, 2) - 1));
-	m = hsv.v - c;
-
-	int angle = hsv.h / 60;
-	switch (angle)
-	{
-	// 0 - 60
-	case 6:
-	case 0:
-		result.r = c;
-		result.g = x;
-		result.b = 0;
-		break;
-	// 60 - 120
-	case 1:
-		result.r = x;
-		result.g = c;
-		result.b = 0;
-		break;
-	// 120 - 180
-	case 2:
-		result.r = 0;
-		result.g = c;
-		result.b = x;
-		break;
-	// 180 - 240
-	case 3:
-		result.r = 0;
-		result.g = x;
-		result.b = c;
-		break;
-	// 240 - 300
-	case 4:
-		result.r = x;
-		result.g = 0;
-		result.b = c;
-		break;
-	// 300 - 360
-	case 5:
-		result.r = c;
-		result.g = 0;
-		result.b = x;
-		break;
-	// Should never happen
-	default:
-		result.r = 0;
-		result.g = 0;
-		result.b = 0;
-		break;
-	}
-	
-	result.r += m;
-	result.g += m;
-	result.b += m;
-
-	return result;
-}
-
-// struct ColourRGB HSLtoRGB(struct ColourHSL hsl)
-// {
-
-// }
-
-struct ColourCMYK RGBtoCMYK(struct ColourRGB rgb)
-{
-	struct ColourCMYK result;
-
-
-	// max(r,g,b)
-	result.k = rgb.r > rgb.g ? rgb.r : rgb.g;
-	result.k = rgb.b > result.k ? rgb.b : result.k;
-	result.k = 1.0 - result.k;
-
-	if (1.0 == result.k)
-	{
-		result.c = 0;
-		result.m = 0;
-		result.y = 0;
-	}
-	else
-	{
-		result.c = (1.0 - rgb.r - result.k) / (1.0 - result.k);
-		result.m = (1.0 - rgb.g - result.k) / (1.0 - result.k);
-		result.y = (1.0 - rgb.b - result.k) / (1.0 - result.k);
-	}
-
-	return result;
-}
-
-struct ColourCMYK HSVtoCMYK(struct ColourHSV hsv)
-{
-	struct ColourCMYK result;
-
-	result = RGBtoCMYK(HSVtoRGB(hsv));
-
-	return result;
-}
-
-struct ColourHSV RGBtoHSV(struct ColourRGB rgb)
-{
-	struct ColourHSV result;
-
-	double c_max;
-	double c_min;
-	double delta;
-
-	// max(r,g,b)
-	c_max = rgb.r > rgb.g ? rgb.r : rgb.g;
-	c_max = rgb.b > c_max ? rgb.b : c_max;
-
-	// min(r,g,b)
-	c_min = rgb.r < rgb.g ? rgb.r : rgb.g;
-	c_min = rgb.b < c_min ? rgb.b : c_min;
-
-	delta = c_max - c_min;
-
-	if (delta > 0)
-	{
-		if (c_max == rgb.r)
-		{
-			result.h = 60 * fmod((rgb.g - rgb.b) / delta, 6);
-		}
-		else if (c_max == rgb.g)
-		{
-			result.h = 60 * ((rgb.b - rgb.r) / delta + 2);
-		}
-		else
-		{
-			result.h = 60 * ((rgb.r - rgb.g) / delta + 4);
-		}
-
-		if(c_max > 0)
-		{
-			result.s = delta / c_max;
-		}
-		else
-		{
-			result.s = 0;
-		}
-
-		result.v = c_max;
-	}
-	else
-	{
-		result.h = 0;
-		result.s = 0;
-		result.v = c_max;
-	}
-
-	if (result.h < 0)
-	{
-		result.h += 360;
-	}
-
-	return result;
-}
-
-struct ColourHSV CMYKtoHSV(struct ColourCMYK cmyk)
-{
-	struct ColourHSV result;
-
-	result = RGBtoHSV(CMYKtoRGB(cmyk));
-
-	return result;
-}
+#include "colours.h"
+
+#include <tgmath.h>
+
+struct ColourRGB CMYKtoRGB(struct ColourCMYK cmyk)
+{
+	struct ColourRGB result;
+
+	result.r = (1.0 - cmyk.c) * (1.0 - cmyk.k);
+	result.g = (1.0 - cmyk.m) * (1.0 - cmyk.k);
+	result.b = (1.0 - cmyk.y) * (1.0 - cmyk.k);
+
+	return result;
+}
+
+struct ColourRGB HSVtoRGB(struct ColourHSV hsv)
+{
+	struct ColourRGB result;
+	double c;
+	double x;
+	double m;
+
+	c = hsv.s * hsv.v;
+	x = c * (1.0 - fabs(fmod(hsv.h / 60.0, 2) - 1.0));
+	m = hsv.v - c;
+
+	int angle = hsv.h / 60;
+	switch (angle)
+	{
+	// 0 - 60
+	case 6:
+	case 0:
+		result.r = c;
+		result.g = x;
+		result.b = 0;
+		break;
+	// 60 - 120
+	case 1:
+		result.r = x;
+		result.g = c;
+		result.b = 0;
+		break;
+	// 120 - 180
+	case 2:
+		result.r = 0;
+		result.g = c;
+		result.b = x;
+		break;
+	// 180 - 240
+	case 3:
+		result.r = 0;
+		result.g = x;
+		result.b = c;
+		break;
+	// 240 - 300
+	case 4:
+		result.r = x;
+		result.g = 0;
+		result.b = c;
+		break;
+	// 300 - 360
+	case 5:
+		result.r = c;
+		result.g = 0;
+		result.b = x;
+		break;
+	// Should never happen
+	default:
+		result.r = 0;
+		result.g = 0;
+		result.b = 0;
+		break;
+	}
+
+	result.r += m;
+	result.g += m;
+	result.b += m;
+
+	return result;
+}
+
+struct ColourRGB HSLtoRGB(struct ColourHSL hsl)
+{
+	struct ColourRGB result;
+	double c;
+	double x;
+	double m;
+
+	c = hsl.s * (1.0 - fabs(2 * hsl.l - 1));
+	x = c * (1.0 - fabs(fmod(hsl.h / 60.0, 2) - 1.0));
+	m = hsl.l - c/2;
+
+	int angle = hsl.h / 60;
+	switch (angle)
+	{
+	// 0 - 60
+	case 6:
+	case 0:
+		result.r = c;
+		result.g = x;
+		result.b = 0;
+		break;
+	// 60 - 120
+	case 1:
+		result.r = x;
+		result.g = c;
+		result.b = 0;
+		break;
+	// 120 - 180
+	case 2:
+		result.r = 0;
+		result.g = c;
+		result.b = x;
+		break;
+	// 180 - 240
+	case 3:
+		result.r = 0;
+		result.g = x;
+		result.b = c;
+		break;
+	// 240 - 300
+	case 4:
+		result.r = x;
+		result.g = 0;
+		result.b = c;
+		break;
+	// 300 - 360
+	case 5:
+		result.r = c;
+		result.g = 0;
+		result.b = x;
+		break;
+	// Should never happen
+	default:
+		result.r = 0;
+		result.g = 0;
+		result.b = 0;
+		break;
+	}
+
+	result.r += m;
+	result.g += m;
+	result.b += m;
+
+	return result;
+}
+
+struct ColourCMYK RGBtoCMYK(struct ColourRGB rgb)
+{
+	struct ColourCMYK result;
+
+	// max(r,g,b)
+	result.k = rgb.r > rgb.g ? rgb.r : rgb.g;
+	result.k = rgb.b > result.k ? rgb.b : result.k;
+	result.k = 1.0 - result.k;
+
+	if (1.0 == result.k)
+	{
+		result.c = 0;
+		result.m = 0;
+		result.y = 0;
+	}
+	else
+	{
+		result.c = (1.0 - rgb.r - result.k) / (1.0 - result.k);
+		result.m = (1.0 - rgb.g - result.k) / (1.0 - result.k);
+		result.y = (1.0 - rgb.b - result.k) / (1.0 - result.k);
+	}
+
+	return result;
+}
+
+struct ColourCMYK HSVtoCMYK(struct ColourHSV hsv)
+{
+	struct ColourCMYK result;
+
+	result = RGBtoCMYK(HSVtoRGB(hsv));
+
+	return result;
+}
+
+struct ColourCMYK HSLtoCMYK(struct ColourHSL hsl)
+{
+	struct ColourCMYK result;
+
+	result = RGBtoCMYK(HSLtoRGB(hsl));
+
+	return result;
+}
+
+struct ColourHSV RGBtoHSV(struct ColourRGB rgb)
+{
+	struct ColourHSV result;
+
+	double c_max;
+	double c_min;
+	double delta;
+
+	// max(r,g,b)
+	c_max = rgb.r > rgb.g ? rgb.r : rgb.g;
+	c_max = rgb.b > c_max ? rgb.b : c_max;
+
+	// min(r,g,b)
+	c_min = rgb.r < rgb.g ? rgb.r : rgb.g;
+	c_min = rgb.b < c_min ? rgb.b : c_min;
+
+	delta = c_max - c_min;
+
+	if (delta > 0)
+	{
+		if (c_max == rgb.r)
+		{
+			result.h = 60 * fmod((rgb.g - rgb.b) / delta, 6);
+		}
+		else if (c_max == rgb.g)
+		{
+			result.h = 60 * ((rgb.b - rgb.r) / delta + 2);
+		}
+		else
+		{
+			result.h = 60 * ((rgb.r - rgb.g) / delta + 4);
+		}
+
+		result.v = c_max;
+		result.s = delta / result.v;
+	}
+	else
+	{
+		result.h = 0;
+		result.s = 0;
+		result.v = c_max;
+	}
+
+	if (result.h < 0)
+	{
+		result.h += 360;
+	}
+
+	return result;
+}
+
+struct ColourHSV CMYKtoHSV(struct ColourCMYK cmyk)
+{
+	struct ColourHSV result;
+
+	result = RGBtoHSV(CMYKtoRGB(cmyk));
+
+	return result;
+}
+
+struct ColourHSV HSLtoHSV(struct ColourHSL hsl)
+{
+	struct ColourHSV result;
+
+	result = RGBtoHSV(HSLtoRGB(hsl));
+
+	return result;
+}
+
+struct ColourHSL RGBtoHSL(struct ColourRGB rgb)
+{
+	struct ColourHSL result;
+
+	double c_max;
+	double c_min;
+	double delta;
+
+	// max(r,g,b)
+	c_max = rgb.r > rgb.g ? rgb.r : rgb.g;
+	c_max = rgb.b > c_max ? rgb.b : c_max;
+
+	// min(r,g,b)
+	c_min = rgb.r < rgb.g ? rgb.r : rgb.g;
+	c_min = rgb.b < c_min ? rgb.b : c_min;
+
+	delta = c_max - c_min;
+
+	if (delta > 0)
+	{
+		if (c_max == rgb.r)
+		{
+			result.h = 60 * fmod((rgb.g - rgb.b) / delta, 6);
+		}
+		else if (c_max == rgb.g)
+		{
+			result.h = 60 * ((rgb.b - rgb.r) / delta + 2);
+		}
+		else
+		{
+			result.h = 60 * ((rgb.r - rgb.g) / delta + 4);
+		}
+
+		result.l = (c_max + c_min) / 2;
+		result.s = delta / (1.0 - fabs(2 * result.l - 1.0));
+	}
+	else
+	{
+		result.h = 0;
+		result.s = 0;
+		result.l = (c_max + c_min) / 2;
+	}
+
+	if (result.h < 0)
+	{
+		result.h += 360;
+	}
+
+	return result;
+}
+
+struct ColourHSL CMYKtoHSL(struct ColourCMYK cmyk)
+{
+	struct ColourHSL result;
+
+	result = RGBtoHSL(CMYKtoRGB(cmyk));
+
+	return result;
+}
+
+struct ColourHSL HSVtoHSL(struct ColourHSV hsv)
+{
+	struct ColourHSL result;
+
+	result = RGBtoHSL(HSVtoRGB(hsv));
+
+	return result;
+}
diff --git a/colours.h b/colours.h
index af57a44..010cb71 100644
--- a/colours.h
+++ b/colours.h
@@ -32,18 +32,18 @@ struct ColourHSL
 
 struct ColourRGB CMYKtoRGB(struct ColourCMYK cmyk);
 struct ColourRGB HSVtoRGB(struct ColourHSV hsv);
-// struct ColourRGB HSLtoRGB(struct ColourHSL hsl);
+struct ColourRGB HSLtoRGB(struct ColourHSL hsl);
 
 struct ColourCMYK RGBtoCMYK(struct ColourRGB rgb);
 struct ColourCMYK HSVtoCMYK(struct ColourHSV hsv);
-// struct ColourCMYK HSLtoCMYK(struct ColourHSL hsl);
+struct ColourCMYK HSLtoCMYK(struct ColourHSL hsl);
 
 struct ColourHSV RGBtoHSV(struct ColourRGB rgb);
 struct ColourHSV CMYKtoHSV(struct ColourCMYK cmyk);
-// struct ColourHSV HSLtoHSV(struct ColourHSL hsl);
+struct ColourHSV HSLtoHSV(struct ColourHSL hsl);
 
 struct ColourHSL RGBtoHSL(struct ColourRGB rgb);
 struct ColourHSL CMYKtoHSL(struct ColourCMYK cmyk);
-// struct ColourHSL HSVtoHSL(struct ColourHSV hsv);
+struct ColourHSL HSVtoHSL(struct ColourHSV hsv);
 
 #endif // COLOURS_H_