title: Flip an Image horizontally
body: <p>I need to flip an image so that a character faces in the right direction. This needs to be done "on the fly' as they say. </p>
  
  <p>The issue I am having is that with Gif images, I seem to lose the transparency. (The background goes white)</p>
  
  <p>Below is the code: (Alternatively someone could send me to a good example)</p>
  
  <pre><code>$img = imagecreatefromgif("./unit.gif");
  
  $size_x = imagesx($img);
  $size_y = imagesy($img);
  
  $temp = imagecreatetruecolor($size_x, $size_y);
  
  imagecolortransparent($img, imagecolorallocate($img, 0, 0, 0));
  imagealphablending($img, false);
  imagesavealpha($img, true);
  
  $x = imagecopyresampled($temp, $img, 0, 0, ($size_x-1), 0, $size_x, $size_y, 0-$size_x, $size_y);
  
  if ($x) {
      $img = $temp;
  }
  else {
      die("Unable to flip image");
  }
  
  header("Content-type: image/gif");
  imagegif($img);
  imagedestroy($img);
  </code></pre>