Color Mixing, Tint, Tone, and Shade in PHP

mix_tint_tone_shade.php

<?php

function mix($color_1 = array(0, 0, 0), $color_2 = array(0, 0, 0), $weight = 0.5)
{
	$f = function($x) use ($weight) { return (1 - $weight) * $x; };
	$g = function($x) use ($weight) { return $weight * $x; };
	$h = function($x, $y) { return round($x + $y); };
	return array_map($h, array_map($f, $color_1), array_map($g, $color_2));
}

function tint($color, $weight = 0.5)
{
	$t = (is_string($color) ? hex2rgb($color) : $color);
	$u = mix($t, array(255,255,255), $weight);
	return (is_string($color) ? rgb2hex($u) : $u);
}

function tone($color, $weight = 0.5)
{
	$t = (is_string($color) ? hex2rgb($color) : $color);
	$u = mix($t, array(128,128,128), $weight);
	return (is_string($color) ? rgb2hex($u) : $u);
}

function shade($color, $weight = 0.5)
{
	$t = (is_string($color) ? hex2rgb($color) : $color);
	$u = mix($t, array(0,0,0), $weight);
	return (is_string($color) ? rgb2hex($u) : $u);
}

function hex2rgb($hex = "#000000")
{
	$f = function($x) { return hexdec($x); };
	return array_map($f, str_split(str_replace("#", "", $hex), 2));
}

function rgb2hex($rgb = array(0, 0, 0))
{
	$f = function($x) { return str_pad(dechex($x), 2, "0", STR_PAD_LEFT); };
	return "#" . implode("", array_map($f, $rgb));
}

print_r("#67ff34");
echo "\n";

print_r(hex2rgb("#67ff34"));
echo "\n";

print_r(rgb2hex(hex2rgb("#67ff34")));
echo "\n";

print_r(tint("#67ff34"));
echo "\n";

print_r(tone("#67ff34"));
echo "\n";

print_r(shade("#67ff34"));
echo "\n";

print_r(shade(hex2rgb("#67ff34")));
echo "\n";

?>