;;; File:
;;;   procedures-lab.scm
;;; Authors:
;;;   Janet Davis
;;;   Samuel A. Rebelsky
;;;   Jerod Weinman
;;;   YOUR NAME HERE
;;; Summary:
;;;   Code for the lab entitled "Writing Your Own Procedures"

; +---------------+-------------------------------------------------------------
; | Some drawings |
; +---------------+

(define black-circle
  (drawing-hshift
   (drawing-vshift
    (drawing-scale drawing-unit-circle 50)
    40)
    30))

(define purple-ellipse
  (drawing-vshift
   (drawing-hshift
    (drawing-vscale
     (drawing-hscale
      (drawing-recolor drawing-unit-circle "purple")
      50)
     25)
    30)
   10))

(define blue-i
  (drawing-recolor
   (drawing-group
    (drawing-hshift
     (drawing-vshift
      (drawing-scale drawing-unit-circle 8)
      4)
     4)
    (drawing-hshift
     (drawing-vshift
      (drawing-hscale
       (drawing-vscale drawing-unit-square 32)
       8)
      28)
     4))
   "blue"))

(define red-eye
  (drawing-hshift
   (drawing-vshift
    (drawing-group
     (drawing-hscale
      (drawing-vscale
       (drawing-recolor drawing-unit-circle "darkgrey")
       24)
      64)
     (drawing-hscale
      (drawing-vscale
       (drawing-recolor drawing-unit-circle "white")
       20)
      60)
     (drawing-hscale
      (drawing-vscale
       (drawing-recolor drawing-unit-circle "red")
       20)
      16))
    12)
   32))

; +----------------------+------------------------------------------------------
; | Drawing transformers |
; +----------------------+

(define variant-1
  (lambda (drawing)
    (drawing-hshift
     (drawing-vshift
      (drawing-scale drawing 1.1)
      20)
     15)))

(define variant-pair-1
  (lambda (drawing)
    (drawing-group drawing (variant-1 drawing))))

(define add-right-neighbor
  (lambda (drawing)
    (drawing-group drawing
                   (drawing-hshift drawing
                                   (drawing-width drawing)))))

; +----------------------+------------------------------------------------------
; | Drawing constructors |
; +----------------------+

(define circle
  (lambda (radius x-center y-center)
    (drawing-hshift
     (drawing-vshift
      (drawing-scale 
       drawing-unit-circle 
       (* 2 radius))
      y-center)
     x-center)))