Graph pane sampe with capi:right-angle-line-pinboard-object

Hello lispworkers,

I would like to specify :type :vertical-first  for all
right-angle-line-pinboard-object's in the following CAPI sample reminding of
the one supplied with LWW 4.3:

(defun node-children (node)
  (when (< node 16)
    (list (* node 2) (1+ (* node 2)))))

(capi:contain (make-instance 'capi:graph-pane
    :roots '(1)
    :children-function 'node-children
    :y-adjust :top
    :edge-pinboard-class 'capi:right-angle-line-pinboard-object)
 :best-width 300
 :best-height 400)

The resulting graph alternates edges among types :vertical-first and
:horizontal-first. So I have altered the code like this:

(capi:contain g (make-instance 'capi:graph-pane
    :roots '(1)
    :children-function 'node-children
    :y-adjust :top
    :edge-pane-function

      (lambda (graph from to)
        (make-instance 'capi:right-angle-line-pinboard-object
                 :type :vertical-first)))
 :best-width 300
 :best-height 400)

Nothing has changed. The grapher seems to create its own edges instead the
ones I am generating manually. Any takers?
--
Sincerely,
Dmitri Ivanov
lisp.ystok.ru