no-reply@allegro.cc (taiwing) — Sat, 02 Dec 2017 21:07:18 +0000

Hello everyone.

I'm currently trying to implement a fullscreen on/off function on my allegro game. It basically consists of destroying the current display and generating a new one in fullscreen mode, or in the game's native resolution if it already was in fullscreen mode.

The problem is, once I activate the function, images drawn before the new display was created can't be displayed, so I get a black screen. So I have to redraw every bitmap needed for the portion of the game I'm in for it to behave normally.

I looked in the allegro manual, but I couldn't find the answer I was looking for. Is this problem unavoidable ?

here's the relevant portion of my code:

#SelectExpand
  1//gameScreen is a structure where I store the display and the buffer of my game
  2void fullScreen(gameScreen *screen)
  3{
if(!screen->fullScreenOnOff)
{
  screen->fullScreenOnOff = true;
  al_destroy_display(screen->display);
  8
  //I get my screen's native resolution
  ALLEGRO_DISPLAY_MODE mode;
  al_get_display_mode(0, &mode);
 12
  //I create a new window
  al_set_new_display_flags(ALLEGRO_FULLSCREEN_WINDOW);
  screen->display = al_create_display(mode.width, mode.height);
}
else
{
  screen->fullScreenOnOff = false;
  al_destroy_display(screen->display);
 21
  //I recreate a window in my game's resolution
  al_set_new_display_flags(ALLEGRO_WINDOWED);
  al_set_new_display_flags(ALLEGRO_RESIZABLE);
  screen->display = al_create_display(SCREEN_W, SCREEN_H);
}
 27}

no-reply@allegro.cc ( Arvidsson) — Sun, 03 Dec 2017 17:02:28 +0000

If you are using a fullscreen window you can switch between fullscreen and windowed without having to destroy anything, eg:

// toggle fullscreen
al_set_display_flag(display, ALLEGRO_FULLSCREEN_WINDOW, !(al_get_display_flags(display) & ALLEGRO_FULLSCREEN_WINDOW));

no-reply@allegro.cc (taiwing) — Sun, 03 Dec 2017 17:43:27 +0000

Ok thank you a lot, you reduced a non-working 25 lines function to a beautiful single line of code

switch FULLSCREEN on and off