show_video_bitmap(3alleg4) [opendarwin man page]

show_video_bitmap(3alleg4)					  Allegro manual					show_video_bitmap(3alleg4)

NAME

       show_video_bitmap - Flips the hardware screen to use the specified page. Allegro game programming library.

SYNOPSIS

       #include <allegro.h>

       int show_video_bitmap(BITMAP *bitmap);

DESCRIPTION

       Attempts to page flip the hardware screen to display the specified video bitmap object, which must be the same size as the physical screen,
       and should have been obtained by calling the create_video_bitmap() function.

       Allegro will handle any necessary vertical retrace synchronisation when page flipping, so you don't need to call vsync()  before  it.  This
       means  that show_video_bitmap() has the same time delay effects as vsync() by default. This can be adjusted with the "disable_vsync" config
       key in the [graphics] section of allegro.cfg. Example:

	  int current_page;
	  BITMAP *video_page[2];
	  ...
	  /* Create pages for page flipping */
	  video_page[0] = create_video_bitmap(SCREEN_W, SCREEN_H);
	  video_page[1] = create_video_bitmap(SCREEN_W, SCREEN_H);
	  current_page = 0;
	  ...
	  /* draw the screen and flip pages */
	  draw_screen(video_page[current_page]);
	  show_video_bitmap(video_page[current_page]);
	  current_page = (current_page+1)%2;
	  ...

RETURN VALUE

       Returns zero on success and non-zero on failure.

SEE ALSO

       scroll_screen(3alleg4), create_video_bitmap(3alleg4), exaccel(3alleg4), exflip(3alleg4), exupdate(3alleg4)

Allegro 							   version 4.4.2					show_video_bitmap(3alleg4)

request_video_bitmap(3alleg4)					  Allegro manual				     request_video_bitmap(3alleg4)

NAME

       request_video_bitmap - Triple buffering page flip request. Allegro game programming library.

SYNOPSIS

       #include <allegro.h>

       int request_video_bitmap(BITMAP *bitmap);

DESCRIPTION

       This  function  is used for triple buffering. It requests a page flip to display the specified video bitmap object, but returns immediately
       rather than waiting for a retrace. The flip 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 on
       certain hardware: see the comments about request_scroll(). Example:

	  int current_page;
	  BITMAP *video_page[3];
	  ...
	  /* Create pages for page flipping */
	  video_page[0] = create_video_bitmap(SCREEN_W, SCREEN_H);
	  video_page[1] = create_video_bitmap(SCREEN_W, SCREEN_H);
	  video_page[2] = create_video_bitmap(SCREEN_W, SCREEN_H);
	  current_page = 0;
	  ...
	  /* draw the screen and flip pages */
	  draw_screen(video_page[current_page]);
	  do {
	  } while (poll_scroll());
	  request_video_bitmap(video_page[current_page]);
	  current_page = (current_page+1)%3;
	  ...

RETURN VALUE

       Returns zero on success and non-zero on failure.

SEE ALSO

       poll_scroll(3alleg4),	request_scroll(3alleg4),    gfx_capabilities(3alleg4),	  create_video_bitmap(3alleg4),    scroll_screen(3alleg4),
       ex3buf(3alleg4), exupdate(3alleg4)

Allegro 							   version 4.4.2				     request_video_bitmap(3alleg4)