vsync(3)                        Allegro manual                        vsync(3)



NAME
       vsync - Waits for a vertical retrace to begin. Allegro game programming
       library.

SYNOPSIS
       #include <allegro.h>


       void vsync();

DESCRIPTION
       Waits for a vertical retrace to begin. The retrace happens when the
       electron beam in your monitor has reached the bottom of the screen and
       is moving back to the top ready for another scan. During this short
       period the graphics card isn't sending any data to the monitor, so you
       can do things to it that aren't possible at other times, such as
       altering the palette without causing flickering (snow). Allegro will
       automatically wait for a retrace before altering the palette or doing
       any hardware scrolling, though, so you don't normally need to bother
       with this function.




SEE ALSO
       set_palette(3), scroll_screen(3)



Allegro                          version 4.2.3                        vsync(3)
