Just spitballing here, but...
Via using a dynamic block, and having lisp draw a bounding box around this block in a new layer, then freezing the bounding box after setting the corners to variables. This would put an invisible bounding box around the inserted dynamic block, and I've seen some samples of this from Lee, read about them from others......but would it be possible to have the visibility state change on the dyn block once the mouse cursor moves within the bounding box? This would in effect create a mouse-over changing block, that could be neat to play with and use as simulations perhaps, for a variety of disciplines.
I know this isn't delving too deep but before I spend any good amount of time with it I was hoping to hear some others thoughts on if this is possible or no...?
