Question about animation

[yanxin <ycui wmsvision com>]

I want to display a series of frames(transparent images) in the 'expose'
event of a drawing area, the call I am using is:
 gdk_pixbuf_render_to_drawable_alpha( psPixbuf, psWidget->window,
  0, 0, sArea.x, sArea.y,
  sArea.width, sArea.height,
  GDK_PIXBUF_ALPHA_BILEVEL, 128,
  GDK_RGB_DITHER_MAX, 0, 0);

But all the frames overlapped with each other! If I call
gdk_window_clear_area () before calling the above function, the image
flashes between frames. How can I draw each frame without causing such
problems?

Another question is, how to make a drawing area transparent on a
gktlayout?

Thanks a lot!

Yanxin