Should capi:graph-pane-object-at-position work with capi:simple-panes nodes?

I have a capi:graph-pane with node representations derived from
capi:simple-pane rather than capi:pinboard-object.

I am trying to use capi:graph-pane-object-at-position to obtain the node
under the cursor in order to be able to select it, but it seems that
this always returns nil (it does work as advertised if I stick with
pinboard-objects).

Is this correct behaviour?
Is there an alternative way of finding out which pane is visible at a
given point?

- Dominic

Re: Should capi:graph-pane-object-at-position work with capi:simple-panes nodes?

The sample code below illustrates the problem.

The even nodes can be selected with the mouse, and double clicking will
print their identity.
The odd nodes can be selected by moving the selection with the cursor
keys (having started from an even node), but mouse clicks do not select
or identify them.

- Dominic

(defclass my-wrapper (capi:row-layout) ())

(defmethod draw-outline (pinboard (self my-wrapper) colour)
  (capi:with-geometry self
    (let ((width (+ capi:%width% 2))
          (height (+ capi:%height% 2))
          (x (- capi:%x% 1))
          (y (- capi:%y% 1)))
      (gp:draw-rectangle pinboard x y width height :foreground colour
      :thickness 1))))

(defmethod capi:draw-pinboard-object (pinboard (self my-wrapper) &key
&allow-other-keys)
  (draw-outline pinboard self (capi:simple-pane-foreground pinboard)))

(defmethod capi:draw-pinboard-object-highlighted (pinboard (self
my-wrapper) &key &allow-other-keys)
  (draw-outline pinboard self (capi:simple-pane-foreground pinboard)))

(defmethod capi:draw-pinboard-object-unhighlighted (pinboard (self
my-wrapper) &key &allow-other-keys)
  (draw-outline pinboard self (capi:simple-pane-background pinboard)))

(defmethod capi:highlight-pinboard-object (pinboard (self my-wrapper)
&key &allow-other-keys)
  (capi:draw-pinboard-object-highlighted pinboard self))

(defmethod capi:unhighlight-pinboard-object (pinboard (self my-wrapper)
&key &allow-other-keys)
  (capi:draw-pinboard-object-unhighlighted pinboard self))

(defun make-graph-node (graph-pane self)
  (if (oddp self)
      (make-instance 'my-wrapper :adjust :centre
                     :description (list (make-instance 'capi:rectangle
                                                       :filled t
                                                       :max-width 12
                                                       :max-height 12
                                                       :graphics-args
                                                       (list :foreground
                                                       (color:make-rgb
                                                       1.0 0.0 0.0)))
                                        (make-instance
                                        'capi:item-pinboard-object
                                                       :text
                                                       (capi:print-collection-item
                                                       self
                                                       graph-pane))))
    (make-instance 'capi:item-pinboard-object
                   :text (capi:print-collection-item self graph-pane))))

(defun node-select (graph x y &optional gspec)
  (declare (ignore gspec))
  (let ((object (capi:graph-pane-object-at-position graph x y)))
    (if object
        (format t "object: ~A node: ~A~%" object
        (capi:graph-object-object object))
      (format t "object not found~%"))))

(defun node-children (node)
  (when (< node 4)
    (list (* node 2)
          (1+ (* node 2)))))

(defun run ()
  (let ((graph (make-instance 'capi:graph-pane
                  :roots '(1)
                  :children-function 'node-children
                  :node-pane-function #'make-graph-node
                  :input-model '(((:button-1 :second-press)
                  node-select)))))
    (capi:contain graph
                  :best-width 300
                  :best-height 400
                  :process nil)))

Re: Should capi:graph-pane-object-at-position work with capi:simple-panes nodes?

I can find the node at a given [x y] by searching the list of graph-node
objects returned by capi:graph-pane-nodes and checking the point against
their extents.  Curious then that graph-pane-object-at-position does
not.

- Dominic

Re: Should capi:graph-pane-object-at-position work with capi:simple-panes nodes?

> Perhaps instead you can get the behaviour you want by defining your
> own subclass of CAPI:ITEM-PINBOARD-OBJECT which draws the red
> rectangle and outline, and use instances of that for the node objects.
> This would also be more efficient than using layouts as the node
> objects.

Oh well - that was how I started out - the red rectangles were for proof
of concept.  With more complex examples it seemed that I was reinventing
the wheel so I thought it was worth a try using the existing layout
machinery to do the work.

Thanks

- Dominic