1request_scroll(3)               Allegro manual               request_scroll(3)
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NAME

6       request_scroll  -  Queues a hardware scroll request with triple buffer‐
7       ing. Allegro game programming library.
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SYNOPSIS

10       #include <allegro.h>
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13       int request_scroll(int x, int y);
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DESCRIPTION

16       This function is used for triple  buffering.  It  requests  a  hardware
17       scroll  to  the specified position, but returns immediately rather than
18       waiting for a retrace. The scroll will then take place during the  next
19       vertical  retrace, but you can carry on running other code in the mean‐
20       time and use the poll_scroll() routine to  detect  when  the  flip  has
21       actually taken place.
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23       Triple buffering is only possible with certain drivers: you can look at
24       the GFX_CAN_TRIPLE_BUFFER bit in the gfx_capabilities flag to see if it
25       will work with the current driver.
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RETURN VALUE

28       This function returns zero on success, non-zero otherwise.
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SEE ALSO

32       poll_scroll(3),      request_video_bitmap(3),      gfx_capabilities(3),
33       scroll_screen(3)
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37Allegro                          version 4.4.2               request_scroll(3)
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