It is possible to set the
slot in a
(setf compound-drawing-object-sub-object). This can be done on any thread. This setting does not cause automatic redisplay of the object. The redisplay happens next the time the hierarchy is redisplayed. You can force the redisplay by calling force-objects-redraw.
compound-drawing-object should not be made by
cl:make-instance. See geometry-drawing-object for how to make it.
compound-drawing-object-data can be used to read and set the
slot in the
compound-drawing-object. You can use the
slot to store related information, and it is used by compute-drawing-object-from-data.
CAPI User Guide and Reference Manual (Windows version) - 3 Aug 2017