CAD tip # 12526:

You can use this add-on application for better readability of line geometry (lines, polylines, splines, arcs, circles, ellipses) on a background, or for creating the geometry of an auxiliar outline in a given distance.

You can download the BufZone add-on application from Download, load it into AutoCAD with APPLOAD and run it by typing the BUFZONE command.

In the initial prompt you can specify the zone width or change the application mode. The Wipeout mode creates wipeouts under the selected geometry, the standard mode creates an outline polyline. You can control the target layer (either by the source line or the current one), whether to create just the outer outline or both for closed polylines, and for creating Wipeouts you can also specify their transparency level (0=none) and the strategy for draworder - by default, the wipeout mask is placed just under the original selected line, the Front mode moves both the line and its wipeout completely to the front (top), above all other drawing geometry.

Using a couple of LISP variables, you can control the app behaviour:

(setq _bufzonearcangle 5.0) ; segmenting angle for arcs
(setq _bufzonelayer "source") ; target layer mode
(setq _bufzoneside "outward") ; mode for outlines for closed polylines
(setq _bufzonetransparency 0) ; wipeout transparency (0-90)
(setq _bufzonedist 1.0) ; preset buffer width
(setq _bufzonewipeout T) ; preset wipeout mode
(setq _bufzonefront T) ; preset Front mode (above all)