fli_bmp_dirty_from man page

fli_bmp_dirty_from, fli_bmp_dirty_to — Indicate which parts of the image have changed. Allegro game programming library.


#include <allegro.h>

extern int fli_bmp_dirty_from;

extern int fli_bmp_dirty_to;


These variables are set by next_fli_frame() to indicate which part of the fli_bitmap has changed since the last call to reset_fli_variables(). If fli_bmp_dirty_from is greater than fli_bmp_dirty_to, the bitmap has not changed, otherwise lines fli_bmp_dirty_from to fli_bmp_dirty_to (inclusive) have altered. You can use these when copying the fli_bitmap onto the screen, to avoid moving data unnecessarily. Example:

if (fli_bmp_dirty_from <= fli_bmp_dirty_to)
   blit(fli_bitmap, screen, 0, fli_bmp_dirty_from,
        0, fli_bmp_dirty_from, fli_bitmap->w,
        fli_bmp_dirty_to - fli_bmp_dirty_from + 1);

See Also

fli_bitmap(3), reset_fli_variables(3)

Referenced By

fli_bitmap(3), reset_fli_variables(3).

Explore man page connections for fli_bmp_dirty_from(3).

fli_bmp_dirty_to(3) is an alias of fli_bmp_dirty_from(3).

Allegro version 4.4.2 Allegro manual