[PHP] Generate a very simple image containing some text

simpletextimage.class.php

<?php
/**
 * Generate a very simple image containing some text
 *
 * Basic usage:
 *    (new SimpleTextImage('Hello world!'))->render();
 *
 * All functionalities:
 *    (new SimpleTextImage())
 *      ->setText('Hello world!')
 *      ->setBackground(255,0,0)
 *      ->setForeground(0,255,255)
 *      ->setFontSize(2)
 *      ->setPadding(10)
 *      ->setFile('hello.jpg')
 *      ->render('jpg');
 *
 */
class SimpleTextImage {
  
  var $text = '';
  var $font_size = 4;
  var $padding = 2;
  var $bg = array(0, 0, 0);
  var $fg = array(255, 255, 255);
  var $file = null;
  
  function __construct($text='')
  {
    $this->text = $text;
  }
  
  function setText($text)
  {
    $this->text = $text;
    return $this;
  }
  
  function setFontSize($font_size)
  {
    $this->font_size = $font_size;
    return $this;
  }
  
  function setPadding($padding)
  {
    $this->padding = $padding;
    return $this;
  }
  
  function setBackground($r, $g, $b)
  {
    $this->bg = array($r, $g, $b);
    return $this;
  }
  
  function setForeground($r, $g, $b)
  {
    $this->fg = array($r, $g, $b);
    return $this;
  }
  
  function setFile($file)
  {
    $this->file = $file;
    return $this;
  }
  
  function render($type = 'png')
  {
    $this->text = str_replace("\r\n", "\n", $this->text);
    
    $lines = explode("\n", $this->text);
    
    $max_nb_chars = 0;
    foreach ($lines as $string)
    {
      $max_nb_chars = max($max_nb_chars, strlen($string));
    }
    
    $char_width = imagefontwidth($this->font_size);
    $char_height = imagefontheight($this->font_size);

    $width = $char_width*$max_nb_chars + $this->padding*2;
    $height = $char_height*count($lines) + $this->padding*2;

    $img = imagecreatetruecolor($width, $height);
    
    $bg = imagecolorallocate($img, $this->bg[0], $this->bg[1], $this->bg[2]);
    imagefilledrectangle($img, 0, 0, $width, $height, $bg);
    
    $fg = imagecolorallocate($img, $this->fg[0], $this->fg[1], $this->fg[2]);

    foreach ($lines as $k => $string)
    {
      for ($i=0, $l=strlen($string); $i<$l; $i++)
      {
        $xpos = $i * $char_width + $this->padding;
        $ypos = $k * $char_height + $this->padding;

        imagechar($img, $this->font_size, $xpos, $ypos, $string[$i], $fg);  
      }
    }

    switch ($type)
    {
    case 'jpg': case 'jpeg':
      if ($this->file == null) header("Content-Type: image/jpeg");
      imagejpeg($img, $this->file, 95);
      break;
      
    case 'gif':
      if ($this->file == null) header("Content-Type: image/gif");
      imagegif($img, $this->file);
      break;
    
    case 'png': default:
      if ($this->file == null) header("Content-Type: image/png");
      imagepng($img, $this->file);
      break;
    }

    imagedestroy($img);
  }
}