Drawing area with different layers

[Chris <plutino gmail com>]

Hi there,

I'm new to gtk programming so this might be a very dummy question.  I
use a DrawingArea to draw a map with three layers: the background map,
the legend window, and app data.  Since the legend layer does not
change often, can I store it in a pixmap and simply copy it rather
than redraw it every time the map and app data change?  I tried the
draw_drawable method, but it doesn't seem to handle tranparency, and
the map behind the legends becomes scribbled.

Thanks for your help.

- Chris