WEB-INF/lib/libchart/classes/view/color/Color.php

   1 <?php
   2         /* Libchart - PHP chart library
   3          * Copyright (C) 2005-2008 Jean-Marc Trémeaux (jm.tremeaux at gmail.com)
   4          *
   5          * This program is free software: you can redistribute it and/or modify
   6          * it under the terms of the GNU General Public License as published by
   7          * the Free Software Foundation, either version 3 of the License, or
   8          * (at your option) any later version.
   9          *
  10          * This program is distributed in the hope that it will be useful,
  11          * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12          * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13          * GNU General Public License for more details.
  14          *
  15          * You should have received a copy of the GNU General Public License
  16          * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17          *
  18          */
  19
  20         /**
  21          * Color.
  22          *
  23          * @author Jean-Marc Trémeaux (jm.tremeaux at gmail.com)
  24          */
  25         class Color {
  26                 private $red;
  27                 private $green;
  28                 private $blue;
  29                 private $alpha;
  30                 private $gdColor;
  31
  32                 /**
  33                  * Creates a new color
  34                  *
  35                  * @param integer red [0..255]
  36                  * @param integer green [0..255]
  37                  * @param integer blue [0..255]
  38                  * @param integer alpha [0..255]
  39                  */
  40                 public function Color($red, $green, $blue, $alpha = 0) {
  41                         $this->red = (int) $red;
  42                         $this->green = (int) $green;
  43                         $this->blue = (int) $blue;
  44                         $this->alpha = (int) round($alpha * 127.0 / 255);
  45
  46                         $this->gdColor = null;
  47                 }
  48
  49                 /**
  50                  * Get GD color.
  51                  *
  52                  * @param $img GD image resource
  53                  */
  54                 public function getColor($img) {
  55                         // Checks if color has already been allocated
  56                         if (!$this->gdColor) {
  57                                 if ($this->alpha == 0 || !function_exists('imagecolorallocatealpha')) {
  58                                         $this->gdColor = imagecolorallocate($img, $this->red, $this->green, $this->blue);
  59                                 } else {
  60                                         $this->gdColor = imagecolorallocatealpha($img, $this->red, $this->green, $this->blue, $this->alpha);
  61                                 }
  62                         }
  63
  64                         // Returns GD color
  65                         return $this->gdColor;
  66                 }
  67
  68                 /**
  69                  * Clip a color component in the interval [0..255]
  70                  *
  71                  * @param integer Component
  72                  * @return Clipped component
  73                  */
  74                 public function clip($component) {
  75                         if ($component < 0) {
  76                                 $component = 0;
  77                         } else if ($component > 255) {
  78                                 $component = 255;
  79                         }
  80
  81                         return $component;
  82                 }
  83
  84                 /**
  85                  * Return a new color, which is a shadow of this one.
  86                  *
  87                  * @param double Multiplication factor
  88                  * @return Shadow color
  89                  */
  90                 public function getShadowColor($shadowFactor) {
  91                         $red = $this->clip($this->red * $shadowFactor);
  92                         $green = $this->clip($this->green * $shadowFactor);
  93                         $blue = $this->clip($this->blue * $shadowFactor);
  94                         $shadowColor = new Color($red, $green, $blue);
  95
  96                         return $shadowColor;
  97                 }
  98         }
  99 ?>