(define (draw-trunk) (separator (rotate -90 (vec3 1 0 0)) (cylinder 'radius .1) )) (define (tree depth) (if (> depth 0) (separator (draw-trunk) (separator (translate (vec3 0 1 0)) (rotate 45 (vec3 0 0 1)) (uscale .75) (tree (- depth 1)) ) (separator (translate (vec3 0 1 0)) (rotate -45 (vec3 0 0 1)) (uscale .7) (tree (- depth 1)) ) ) ) )