<?php
function ColorLuminance($hex, $lum)
{
// validate hex string
$hex = preg_replace("/[^0-9a-f]/i", "", $hex);
if (strlen($hex) < 6) {
$hex = $hex[0] . $hex[0] . $hex[1] . $hex[1] . $hex[2] . $hex[2];
}
// convert to decimal and change luminosity
$rgb = "#";
for ($i = 0; $i < 3; $i++) {
//echo substr($hex, $i * 2, 2) . " * ";
$c = base_convert(substr($hex, $i * 2, 2), 16, 10);
//echo $c . " - ";
$c = base_convert((round(min(max(0, floatval($c + ($c * $lum))),255))), 10, 16);
//echo $c . " - ";
$rgb .= substr('00' . $c, strlen($c));
//echo $rgb . " - ";
}
return $rgb;
}
echo ColorLuminance("#69c", 0) . "\n"; // returns "#6699cc"
/*echo ColorLuminance("6699CC", 0.2) . "\n";// "#7ab8f5" - 20% lighter
echo ColorLuminance("69C", -0.5) . "\n";// "#334d66" - 50% darker
echo ColorLuminance("000", 1) . "\n";// "#000000" - true black cannot be made lighter!*/
- Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.5 - 7.2.33, 7.3.12 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
- #6699cc
preferences:
255.91 ms | 406 KiB | 312 Q