include DXOpal

Image.register(:ufo, 'images/ufo.png') 

Window.load_resources do
  img = Image[:ufo]
  startdeg = 0
  
  Window.loop do
    # Window.draw_box_fill(0, 0, Window.width, Window.height, [0, 0, 0])
    
    bx = 0
    by = Window.height / 2

    tx = Input.mouse_x
    ty = Input.mouse_y

    nmax = 32
    dw = tx - bx
    dh = ty - by
    deg = startdeg
    h = 100
    nmax.times do |i|
      x = bx + (dw * i / nmax) - img.width / 2
      y = by + (dh * i / nmax) - img.height / 2
      hh = h * i / nmax
      y += hh * Math.sin(deg * Math::PI / 180.0)
      Window.draw(x, y, img)
      deg += 15
    end

    startdeg += 10
  end
end