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scroll_screen(3)		Allegro	manual		      scroll_screen(3)

NAME
       scroll_screen  -	 Requests a hardware scroll request. Allegro game pro-
       gramming	library.

SYNOPSIS
       #include	<allegro.h>

       int scroll_screen(int x,	int y);

DESCRIPTION
       Attempts	to scroll the hardware screen to display a different  part  of
       the  virtual  screen (initially it will be positioned at	0, 0, which is
       the top left corner). You can use  this	to  move  the  screen  display
       around  in a large virtual screen space,	or to page flip	back and forth
       between two non-overlapping areas of the	virtual	screen.	Note  that  to
       draw  outside  the original position in the screen bitmap you will have
       to alter	the clipping rectangle with set_clip_rect().

       Mode-X scrolling	is reliable and	will work on any card,	other  drivers
       may not work or not work	reliably. See the platform-specific section of
       the docs	for more information.

       Allegro will handle any necessary vertical retrace synchronisation when
       scrolling the screen, so	you don't need to call vsync() before it. This
       means that scroll_screen() has the same time delay effects as vsync().

RETURN VALUE
       Returns zero on success.	Returns	non-zero if the	graphics driver	 can't
       handle hardware scrolling or the	virtual	screen is not large enough.

SEE ALSO
       set_gfx_mode(3),	    show_video_bitmap(3),    request_scroll(3),	   re-
       quest_video_bitmap(3), exscroll(3)

Allegro				 version 4.4.3		      scroll_screen(3)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | SEE ALSO

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