Adding Colorsys object (for playing with colors)

library/Taplod/Colorsys.php

@@ -0,0 +1,166 @@
+<?php
+/**
+ * @category Taplod
+ * @package Taplod_Colorsys
+ * @copyright Copyright (c) 2009, Bellière Ludovic
+ * @license http://opensource.org/licenses/mit-license.php MIT license
+ */
+
+class Taplod_Colorsys {
+
+	const HEX = 'hex';
+	const RGB = 'rgb';
+
+	protected $_type;
+	protected $_color = array(
+		self::HEX => '',
+		self::RGB => ''
+	);
+	protected $_current_color;
+
+	function __construct($color) {
+		if (!is_array($color)) {
+			if ($color == 'random')
+				$color = self::random('hex');
+			$color = str_replace('#','',$color);
+			$this->_type = self::HEX;
+			$this->_current_color = $color;
+			$this->_color = array(
+				self::RGB => self::hex2rgb(),
+				self::HEX => $color
+			);
+		} else {
+			$this->_type = self::RGB;
+
+			$this->_current_color = $color;
+			$this->_color = array(
+				self::RGB => $color,
+				self::HEX => $color
+			);
+		}
+	}
+
+	function getRgb() {
+		return $this->_color[self::RGB];
+	}
+
+	function getHex() {
+		return $this->_color[self::HEX];
+	}
+
+	function revert($hex=false) {
+		if (!$hex) {
+			if ($this->_type == self::HEX)
+				$hex = $this->_current_color;
+			else
+				return $this->_current_color;
+		} else {
+			if ($hex[0] == "#") {
+				$hex = substr($hex,1);
+			}
+		}
+
+		$r = str_pad(dechex(255 - hexdec(substr($hex,0,2))),2,0);
+		$g = str_pad(dechex(255 - hexdec(substr($hex,2,2))),2,0);
+		$b = str_pad(dechex(255 - hexdec(substr($hex,-2))),2,0);
+
+		return "#$r$g$b";
+	}
+
+	function rgb2hex($rgb=false) {
+		if (!$rgb) {
+			if ($this->_type == self::RGB)
+				$rgb = $this->_current_color;
+			else
+				return $this->current_color;
+		} else {
+			if (!is_array($rgb)) {
+				throw new exception('Invalid type given for RGB. An array is expected, '.gettype($rgb).' given.');
+			}
+		}
+
+		$r = dechex(substr($rgb,0,3));
+		$g = dechex(substr($rgb,0,3));
+		$b = dechex(substr($rgb,-3));
+
+		return compact('r','g','b');
+	}
+
+	function hex2rgb($hex=false) {
+		if (!$hex) {
+			if ($this->_type == self::HEX)
+				$hex = $this->_current_color;
+			else
+				return $this->_current_color;
+		}
+
+		$r = hexdec(substr($hex,0,2));
+		$g = hexdec(substr($hex,2,2));
+		$b = hexdec(substr($hex,-2));
+
+		return compact('r', 'g', 'b');
+	}
+
+	static function rgb2hsv($r, $g=0, $b=0) {
+		if (is_array($r) && count($r)==3) {
+			$b = $r['b'];
+			$g = $r['g'];
+			$r = $r['r'];
+		}
+		$max = max($r, $g, $b);
+		$min = min($r, $g, $b);
+		$delta = $max-$min;
+
+		if ($max == 0)
+			return array('h'=>0, 's'=>0, 'v'=>0);
+
+		$s = $delta / $max;
+		$v = $max;
+
+		switch ($max) {
+			case $g:
+				if ($delta != 0) {
+					$h = 2 + ($b - $r) / $delta;
+				} else {
+					$s = 0;
+					$h = 2 + $b - $r;
+				}
+				break;
+			case $b:
+				if ($delta != 0) {
+					$h = 4 + ($r - $g) / $delta;
+				} else {
+					$s = 0;
+					$h = 4 + $r - $g;
+				}
+				break;
+			case $r:
+				if ($delta != 0) {
+					$h = ($g - $b) / $delta;
+				} else {
+					$h = $g - $b;
+				}
+				break;
+		}
+
+		$h*=60;
+		if ($h<0)
+			$h+=360;
+		$h = round($h);
+		$s = round($s*255);
+
+		return compact('h','s','v');
+	}
+
+	static function random($format='dec') {
+		$color = rand(0, hexdec('ffffff'));
+		if ($format=='hex') {
+			return dechex($color);
+		} else {
+			return array(
+				'r' => substr($color,0,2),
+				'b' => substr($color,2,2),
+				'r' => substr($color,-2));
+		}
+	}
+}