code: protected function getTotalWidth()
  	{
  		$borders = (static::BORDER_WIDTH + static::MIN_SPACE_FROM_BORDER_X) * 2;
  		
  		if(empty($this->pipes))
  		{
  			return $borders + $this->getCoreLength();
  		}
  
  		$borders *= count($this->pipes);
  
  		$name = ($this->getLongestPipeLength() + static::SPACE_FROM_ARROW) * 2;
  
  		return $borders + $name + static::ARROW_WIDTH;
  	}
docs: Calculate the total width of the drawing.
  
  @author	Andrea Marco Sartori
  @return	integer