Re: erasing (cleaning) drawing area

[Dan Rosen <dr cs brown edu>]

Since a drawing area is nothing more than an X window (which you have to
manage yourself), you need to write your own clear function. This will
probably just mean something like:

  define a gdk_rectangle the size of the drawing area
  draw it onto the backing pixmap in white
  copy the backing pixmap to the canvas

If you copied the "scribble" example, you should be able to steal all of
the code you'll need from the configure_event and exposure_event code.

Dan