Lee McDonnell has contributed an AutoCAD routine that constructs tangent lines between two or more circles. Start by loading the LISP file and enter the command CE. Select the first circle, then select additional circles as needed, one at a time. When you are done, click anywhere to end the command. Tangent lines will be constructed to form an enclosure around all selected circles. Lee's code provides several examples of how to use functions such as (mapcar) and (lambda) as well as several (vl- ) functions; he has also provided an animated image showing this code in action. |