/**
  * Sets the character height of a character
  * @param mixed $ch a character
  * @param float $h  height
  */
 public function setCharacterHeight($ch, $h)
 {
     if ($this->direction != -1) {
         $this->font_metrics[$this->direction]->setCharacterHeight($ch, $h);
     } else {
         parent::setCharacterHeight($ch, $h);
     }
 }