*The Co-ordinate System:*

- Specify points with
`pt(x,y)` - Specify rectangles with
`rect(x,y,width,height)` - The co-ordinate (0,0) is at the top left of the window or drawing area:

*Using Points and Rectangles:*

- Find the rectangle of a control with
`r = get_control_area(c)` - Find the rectangle of a window with
`r = get_window_area(w)` - Inset a rectangle with
`r2 = inset_rect(r,1)` - Center a rectangle on another with
`r3 = center_rect(r1,r2)` - Are two rectangles equal?
`rects_equal(r1,r2)` - Are two points equal?
`points_equal(p1,p2)` - Is a point inside a rect?
`point_in_rect(p,r)`