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request_scroll(3)		Allegro	manual		     request_scroll(3)

NAME
       request_scroll  -  Queues a hardware scroll request with	triple buffer-
       ing. 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	 retrace, but you can carry on running other code in the mean-
       time and	use the	poll_scroll() routine to detect	when the flip has  ac-
       tually 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 4.4.2		     request_scroll(3)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | SEE ALSO

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