; (define-struct posn (x y))      ; Included from draw.ss.
;
; A <i>posn</i> is:
;   - (make-posn <var>num</var> <var>num</var>)
;
; Examples:
(define origin (make-posn 0 0))
(define p34    (make-posn 3 4))


; A <i>color</i> is one of {'red, 'yellow, 'white, 'black, 'blue, 'green}.
;
;  Examples of color: (explicitly enumerated in data def'n).

;; translate: posn, num, num --&gt; posn
;; Return the point which is a-point offset by (+x, +y).
;;
(define (translate a-point x y)
  (make-posn (+ (posn-x a-point) x)
             (+ (posn-y a-point) y)))

(translate p34 5 12) = (make-posn 8 16)
(translate origin 3 4) = p34
(translate p34 -3 -4) = origin


(define-struct circle (location radius color))
;
; A <i>circle</i> is:
;    (make-circle <var>posn</var> <var>num</var> <var>symbol</var> <var>color</var>)
;
; Examples of circles:
;
(define circ1  (make-circle p34     1 'red))    ; A little red dot.
(define circ23 (make-circle origin 23 'blue))    

(define-struct rectangle (location width height color))

;A <i>rectangle</i> is:
;    (make-rectangle <var>posn</var> <var>num</var> <var>num</var> <var>color</var>)
;
;Examples:
(define rect1 (make-rectangle (make-posn 10 10) 15 30 'yellow))
(define rect2 (make-rectangle (make-posn  0  0)  2  2 'red))




;; A shape is a structure that contains
;; - a circle, or
;  (;make-posn  posn? posn-x posn-y
;   translate-shape draw-shape draw-shapes circle-tool rectangle-tool
;   circ1 rect1))

(define translate-shape 3)
(define draw-shape 4)
(define draw-shapes 5)
(define circle-tool 3)
(define rectangle-tool 6)
;(define circ1 7)
;(define rect1 8)