[gtkada] Preserving background pixmap when animating (CONTINUED...)

[Emmanuel Briot]

 > My problem is not with flicker, it is with the background pixmap getting 
 > wiped over. In short can you animate the drawing area with pixmaps that have 
 > transparency , AND also preseve the background of the drawing area......may 
 > be by applying the background pixmap to the Transparency!...(that should do 
 > it)

You did report a problem with flickering in your original email :-)

Anyway, the solution is trivial, and in fact completely standard when one does
animation: you need to redraw the part of the background pixmap that was below
the item, then draw the items on top of it. To do this, you need to use a
double_buffer or things will really flicker too much, and we are back to the
double_buffer widget.


 > Can you in Gtkada draw on to the drawing area (or some widget) with a 
 > trasparent color, so that the widget will become transparent. (useful for 
 > also custom shaped window!)

I don't understand this part. Transparent means that nothing is drawn, this is
not a color!
And since windows are not handled by your application itself but by the window
manager itself, using transparent pixmaps is definitely not the way to get
custom shapes. This is in fact part of a gdk package that is not bound in
GtkAda (can't remember the name though), since it wasn't portable across
systems.

Emmanuel