Reply To: Convert hexadecimal value to HSL

• jarvis

• November 11, 2021 at 11:21 am

This removes the #

<?php 
$hex = '#f00';
$hex = str_replace('#', '', $hex);
echo $hex;

So altogether:

<?php 
$hex = get_field('hex_colour');
$hex = str_replace('#', '', $hex);
echo hexToHsl($hex);

The function:

<?php

function hexToHsl($hex){
    $red = hexdec(substr($hex, 0, 2)) / 255;
    $green = hexdec(substr($hex, 2, 2)) / 255;
    $blue = hexdec(substr($hex, 4, 2)) / 255;

    $cmin = min($red, $green, $blue);
    $cmax = max($red, $green, $blue);
    $delta = $cmax - $cmin;

    if ($delta == 0) {
        $hue = 0;
    } elseif ($cmax === $red) {
        $hue = (($green - $blue) / $delta);
    } elseif ($cmax === $green) {
        $hue = ($blue - $red) / $delta + 2;
    } else {
        $hue = ($red - $green) / $delta + 4;
    }

    $hue = round($hue * 60);
    if ($hue < 0) {
        $hue += 360;
    }

    $lightness = (($cmax + $cmin) / 2);
    $saturation = $delta === 0 ? 0 : ($delta / (1 - abs(2 * $lightness - 1)));
    if ($saturation < 0) {
        $saturation += 1;
    }

    $lightness = round($lightness*100);
    $saturation = round($saturation*100);

     return "hsl(${hue}, ${saturation}%, ${lightness}%)";

    //return array($hue, $saturation, $lightness);
    }