OKLCH to HSL Color Converter

Mathematical Formula for OKLCH to HSL Conversion

// Step 1: Convert OKLCH to Oklab
oklab_L = oklch_L
oklab_a = oklch_C × cos(oklch_H × π/180)
oklab_b = oklch_C × sin(oklch_H × π/180)

// Step 2: Convert Oklab to XYZ color space
f_L = (oklab_L + 0.3963377774) / 1.0909090909
f_a = oklab_a / 0.2104542553
f_b = oklab_b / 0.0063467324

Y = f_L³
X = (f_a + 1.9779984951 × f_L) / 2.2799829554
Z = (f_L - f_b - 0.8392685158 × f_a) / 1.1910996938

// Step 3: Convert XYZ to RGB
R = X × 3.2406 + Y × (-1.5372) + Z × (-0.4986)
G = X × (-0.9689) + Y × 1.8758 + Z × 0.0415
B = X × 0.0557 + Y × (-0.2040) + Z × 1.0570

// Step 4: Apply gamma correction
R = gamma_correct(R)
G = gamma_correct(G)
B = gamma_correct(B)

// Step 5: Convert RGB to HSL
max_rgb = max(R, G, B)
min_rgb = min(R, G, B)
delta = max_rgb - min_rgb

// Calculate HSL Lightness
hsl_L = (max_rgb + min_rgb) / 2

// Calculate HSL Saturation
if (delta == 0) {
    hsl_S = 0
} else {
    hsl_S = delta / (2 - max_rgb - min_rgb) if hsl_L > 0.5
    hsl_S = delta / (max_rgb + min_rgb) if hsl_L ≤ 0.5
}

// Calculate HSL Hue
if (delta == 0) {
    hsl_H = 0
} else if (max_rgb == R) {
    hsl_H = ((G - B) / delta) % 6
} else if (max_rgb == G) {
    hsl_H = (B - R) / delta + 2
} else {
    hsl_H = (R - G) / delta + 4
}
hsl_H = hsl_H × 60