graphene:rect-center (rect point)

rect -- a graphene:rect-t instance
point -- a graphene:point-t instance

The graphene:point-t instance.

Retrieves the coordinates of the center of the given rectangle.

(graphene:with-rect (rect 0 0 10 20)
  (graphene:with-point (point)
    (graphene:rect-center rect point)
    (values (graphene:point-x point)
            (graphene:point-y point))))
=> 5.0
=> 10.0