create_sub_bitmap (3) - Linux Man Pages
create_sub_bitmap: Creates a memory sub bitmap. Allegro game programming library.
create_sub_bitmap - Creates a memory sub bitmap. Allegro game programming library.
BITMAP *create_sub_bitmap(BITMAP *parent, int x, y, width, height);
Creates a sub-bitmap, ie. a bitmap sharing drawing memory with a
pre-existing bitmap, but possibly with a different size and clipping
settings. When creating a sub-bitmap of the mode-X screen, the x position
must be a multiple of four. The sub-bitmap width and height can extend
beyond the right and bottom edges of the parent (they will be clipped),
but the origin point must lie within the parent region.
Returns a pointer to the created sub bitmap, or NULL if the sub bitmap
could not be created. Remember to free the sub bitmap before freeing
the parent bitmap to avoid memory leaks and potential crashes accessing
memory which has been freed.