# File lib/rubygame/music.rb, line 340
  def fade_out( fade_time )
    if( fade_time < 0 )
      raise ArgumentError, "fade time cannot be negative (got %.2f)"%fade_time
    end

    if current?
      result = SDL::Mixer.FadeOutMusic( (fade_time * 1000).to_i )
      if( result < 0 )
        raise Rubygame::SDLError, "Error fading out music: #{SDL.GetError()}"
      end
    end

    return self
  end