poll_scroll(3alleg4) [opendarwin man page]

poll_scroll(3alleg4)						  Allegro manual					      poll_scroll(3alleg4)

NAME

       poll_scroll - Checks the status of a scroll request with triple buffering. Allegro game programming library.

SYNOPSIS

       #include <allegro.h>

       int poll_scroll();

DESCRIPTION

       This function is used for triple buffering. It checks the status of a hardware scroll previously initiated by the request_scroll() routine.

RETURN VALUE

       Returns non-zero if it is still waiting to take place, and zero if the requested scroll has already happened.

SEE ALSO

       request_scroll(3alleg4), request_video_bitmap(3alleg4), ex3buf(3alleg4), exupdate(3alleg4)

Allegro 							   version 4.4.2					      poll_scroll(3alleg4)

request_scroll(3alleg4) 					  Allegro manual					   request_scroll(3alleg4)

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 retrace, 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(3alleg4), request_video_bitmap(3alleg4), gfx_capabilities(3alleg4), scroll_screen(3alleg4)

Allegro 							   version 4.4.2					   request_scroll(3alleg4)