TickitRect - utility structure representing a rectangular region
#include <tickit.h>
typedef struct {
int top;
int left;
int lines;
int cols;
} TickitRect;
A TickitRect structure represents a single non-empty rectangular region
of the screen. It stores the position of the top left corner of the region,
and its size in lines and columns.
A new TickitRect structure can be initialised using the
tickit_rect_init_sized(3) and tickit_rect_init_bounded(3)
functions. Its bottom right corner can be obtained using
tickit_rect_bottom(3) and tickit_rect_right(3). Interactions
between rectangles can be tested using the predicate functions
tickit_rect_contains(3) and tickit_rect_intersects(3). New
rectangles can be created from existing ones using
tickit_rect_intersect(3) to form the intersection,
tickit_rect_add(3) to form the union sum, and
tickit_rect_subtract(3).