(define create-drawing 
  (let ((iriscolors 
         (list color.navy-blue 
               color.blue 
               color.light-blue 
               color.medium-grey 
               color.bakers-chocolate 
               color.brown 
               color.sienna 
               color.hunter-green 
               color.medium-forest-green 
               color.pale-green 
               color.red)) 
        (brushes 
         (list "Circle (01)" "Circle (03)" "Circle (05)" "Circle (07)" "Circle (09)"))) 
    (lambda (filename val1 val2 val3) 
      (let* ((eye-height 80) 
             (eye-width 160) 
             (iriscolor (list-ref iriscolors val1)) 
             (iris-diameter 80) 
             (lash-brush (list-ref brushes (modulo val3 5))) 
             (pupil-diameter (* iris-diameter (+ 0.05 (/ val2 10)))) 
             (pupil-left (- 99 (* 40 (/ val2 10)))) 
             (pupil-top (- 99 (* 40 (/ val2 10)))) 
             (destination (open-output-file filename))) 
        (if (not (output-port? destination)) 
            (throw "create-drawing: Could not open output file" filename)) 
        ; Write the sclera ("that white part" for non-bio majors). 
        (empty-ellipse.write destination 
                                color.black 
                                "Circle (03)" 
                                20
                                60
                                eye-width 
                                eye-height) 
        ; Write the iris 
        (filled-circle.write destination 
                                iriscolor 
                                60 60 iris-diameter) 
        ; Draw the pupil 
        (filled-circle.write destination 
                    color.black 
                    pupil-left 
                    pupil-top 
                    pupil-diameter) 
        ; Draw the lashes 
        (line.write destination 
                    color.black 
                    lash-brush 
                    25 85 
                    25 65) 
        (line.write destination 
                    color.black 
                    lash-brush 
                    50 69 
                    50 49) 
        (line.write destination 
                    color.black 
                    lash-brush 
                    75 62 
                    75 42) 
        (line.write destination 
                    color.black 
                    lash-brush 
                    100 60 
                    100 40) 
        (line.write destination 
                    color.black 
                    lash-brush 
                    125 62 
                    125 42) 
        (line.write destination 
                    color.black 
                    lash-brush 
                    150 69 
                    150 49) 
        (line.write destination 
                    color.black 
                    lash-brush 
                    175 85 
                    175 65) 
        (close-output-port destination) 
        '"Ira is watching you."))))