Hi, I’ve noticed that in X if SDL runs in windowed mode
it dosn’t keep the window content if it’s not refreshed…
Ehm, I’ll provide an example as my English is not that good…
SDL pseudo code:
/* (lost it’s contents) */
initialization;
load_a_bmp_onto_a_surface;
blit_the_bmp_onto_screen_surface;
wait_5_seconds;
quit;
/* this is ok */
initialization;
load_a_bmp_onto_a_surface;
blit_the_bmp_onto_screen_surface;
while_!_end_of_app
{
update_the_screen;
if_esc_is_pressed
break;
}
quit;--------
Ok, now at runtime if I drag another window
onto the SDL window this one lost it’s content.
Is this a normal ?
(If I remember, this was not happening with older SDL versions,
or maybe with older XFree versions).
Thanks,
G.Gabriele
Hi, I’ve noticed that in X if SDL runs in windowed mode
it dosn’t keep the window content if it’s not refreshed…
SDL will update the window with the contents of the back-buffer when
you call SDL_UpdateRects (or SDL_UpdateRect, SDL_Flip), and when
it receives an expose event (which happens right after the window is
mapped and whenever a portion of it needs redrawing for some reason).
For this to happen, you must events to be processed; either by checking
for events in your loop (PollEvents, PeepEvents or WaitEvent) or by
calling PumpEvents
SDL will request a backing store for the window which means that most
redrawing will happen automatically without expose events (unless
backing store is refused for some reason)
(If I remember, this was not happening with older SDL versions,
or maybe with older XFree versions).
my guess is that your new X server has backing-store switched off. Use
xdpyinfo to find out
<-- SNIP -->
(If I remember, this was not happening with older SDL versions,
or maybe with older XFree versions).
my guess is that your new X server has backing-store switched off. Use
xdpyinfo to find out
Good guess 
screen #0:
…
options: backing-store NO, save-unders NO
Thanks a million,
G.Gabriele