Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help
request_scroll(3)		 Allegro manual 	       request_scroll(3)

NAME
     request_scroll  -	Queues	a hardware scroll request with triple buffering.
     Allegro game programming library.

SYNOPSIS
     #include <allegro.h>

     int request_scroll(int x, int y);

DESCRIPTION
     This function is used for triple buffering. It requests a	hardware  scroll
     to  the specified position, but returns immediately rather than waiting for
     a retrace. The scroll will then take place during	the  next  vertical  re-
     trace,  but you can carry on running other code in the meantime and use the
     poll_scroll() routine to detect when the flip has actually taken place.

     Triple buffering is only possible with certain drivers: you can look at the
     GFX_CAN_TRIPLE_BUFFER bit in the gfx_capabilities flag to see  if	it  will
     work with the current driver.

RETURN VALUE
     This function returns zero on success, non-zero otherwise.

SEE ALSO
     poll_scroll(3),	    request_video_bitmap(3),	    gfx_capabilities(3),
     scroll_screen(3)

Allegro 			  version 4.4.3 	       request_scroll(3)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=request_scroll&sektion=3&manpath=FreeBSD+Ports+15.1.quarterly>

home | help