Skip to content

Instantly share code, notes, and snippets.

@BoShurik
Created February 21, 2018 10:18
Show Gist options
  • Save BoShurik/0dd5b7eb148d72e697afa7350dfe19df to your computer and use it in GitHub Desktop.
Save BoShurik/0dd5b7eb148d72e697afa7350dfe19df to your computer and use it in GitHub Desktop.
Color value object
<?php
final class Color
{
private $name;
/**
* @param integer $r [0, 255]
* @param integer $g [0, 255]
* @param integer $b [0, 255]
* @return Color
*/
public static function fromRGB($r, $g, $b)
{
if ($r < 0 || $r > 255) {
throw new \InvalidArgumentException('Invalid value for R component');
}
if ($g < 0 || $g > 255) {
throw new \InvalidArgumentException('Invalid value for G component');
}
if ($b < 0 || $b > 255) {
throw new \InvalidArgumentException('Invalid value for B component');
}
$color = new self();
$color->name = sprintf('%02X%02X%02X', $r, $g, $b);
return $color;
}
/**
* @param integer $h [0, 360]
* @param float $s [0, 1]
* @param float $l [0, 1]
* @return Color
*/
public static function fromHSL($h, $s, $l)
{
if ($h < 0 || $h > 360) {
throw new \InvalidArgumentException('Invalid value for H component');
}
if ($s < 0 || $s > 1) {
throw new \InvalidArgumentException('Invalid value for S component');
}
if ($s < 0 || $s > 1) {
throw new \InvalidArgumentException('Invalid value for L component');
}
$h = $h / 360;
if ($s == 0) {
return self::fromRGB(round($l * 255), round($l * 255), round($l * 255));
}
$q = $l < 0.5 ? $l * (1 + $s) : $l + $s - $l * $s;
$p = 2 * $l - $q;
$r = self::HUEtoRGB($p, $q, $h + 1/3);
$g = self::HUEtoRGB($p, $q, $h);
$b = self::HUEtoRGB($p, $q, $h - 1/3);
return self::fromRGB(round($r * 255), round($g * 255), round($b * 255));
}
/**
* @param float $p
* @param float $q
* @param float $t
* @return float
*/
private static function HUEtoRGB($p, $q, $t)
{
if($t < 0) {
$t += 1;
}
if($t > 1) {
$t -= 1;
}
if($t < 1/6) {
return $p + ($q - $p) * 6 * $t;
}
if($t < 1/2) {
return $q;
}
if($t < 2/3) {
return $p + ($q - $p) * (2/3 - $t) * 6;
}
return $p;
}
public function __toString()
{
return $this->name;
}
private function __construct()
{
}
}
$d = 360 / 5;
$colors = [];
for ($i = 0; $i < 360; $i += $d) {
$color = Color::fromHSL($i, 0.7, 0.5);
$colors[] = (string)$color;
}
echo json_encode(array_map(function($value){
return '#'.$value;
}, $colors)) . "\n\n";
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment