Feedback on new rain script

[deValdr]

Basically, I wrote a script for new rain visuals. I am going to use it in my game so it is not for reuse at this point. Feedback?

Code:

class Scene_Map  
  alias old_init_valdred initialize
  def initialize
    old_init_valdred
    @weather = Sprite.new
    @weather.bitmap = Bitmap.new(640,480)
    @weather.z = 99998
    @t = Sprite.new
    @t.bitmap = Bitmap.new(640, 480)
    @t.bitmap.font.color = Color.new(0,0,0)
    @t.bitmap.draw_text(0,0,640,20,"Not for use. Not for redistribution", 1)
    @t.bitmap.draw_text(0,460,640,20,"Save-Point.org - Valdred", 1)
    @t.z = 99999
  end
  def draw_rain
    # Reset bitmap
    @weather.bitmap.clear
    # Draw rain
    for i in 1..60
      c = Color.new(225,225,225,100)
      x = rand(640)
      y = rand(480)
      w = 1
      h = rand(75) + 10
      @weather.bitmap.fill_rect(x, y, w, h, c)
      # Extend weather
      y += rand(25)
      h -= rand(5)
      c.alpha -= rand(80)
      @weather.bitmap.fill_rect(x, y, w, h, c)
      # Add splash
      bitmap = Bitmap.new(32,32)
      bitmap.set_pixel(12,14,Color.new(225,225,225))
      bitmap.set_pixel(13,16,Color.new(225,225,225))
      bitmap.set_pixel(14,15,Color.new(225,225,225))
      bitmap.set_pixel(14,18,Color.new(225,225,225))
      bitmap.set_pixel(15,18,Color.new(225,225,225))
      bitmap.set_pixel(16,18,Color.new(225,225,225))
      bitmap.set_pixel(17,18,Color.new(225,225,225))
      bitmap.set_pixel(15,17,Color.new(225,225,225))
      bitmap.set_pixel(17,17,Color.new(225,225,225))
      rect = bitmap.rect
      @weather.bitmap.blt(x, y + h, bitmap, rect, 150)
    end
  end
  alias update_old_valdred update
  def update
    update_old_valdred
    draw_rain
  end
end