NAME

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

SYNOPSIS

       #include <allegro.h>

       extern int fli_bmp_dirty_from;

       extern int fli_bmp_dirty_to;

DESCRIPTION

       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(3alleg4), reset_fli_variables(3alleg4)