BB Pro Boundary Builder for AutoCAD


BB Pro is an AutoLisp program that helps you covert a collection of lines, arcs and open polylines into closed polylines. Why? Many translators from AutoCAD to formats such as GDSII and Gerber require regions that are defined by zero width closed polylines. Converting a drawing done using lines and arcs into closed polylines manually is very time consuming. BBPRO can reduce a one hour job to one minute.

How it Works

Make the layer you wish to clean the current layer.

Select the entities you wish to convert using any of AutoCAD's selection methods - window, crossing etc ...

BB Pro then collects the lines, arcs and unclosed polylines (only those with zero width) and selects one of those entities as a starting point. It then searches for an endpoint on or near the starting point. If one is detected, it makes a connection and repeats the process. If it eventually closes back on the starting point a closed boundary has been created and this is converted into a closed polyline.

If while building a closed boundary it cannot find a connection point (or it finds multiple candidates) the program zooms in and asks the user to click on the connecting section.

Once complete, your drawing has all clean closed polylines on a boundary layer and leftover lines and arcs on an open layer. Cleanup operations that took hours by hand are done in minutes with BB Pro.

BBPRO only works in the English version of AutoCAD. It does not work with AutoCAD Lite since that has no Lisp engine.


BB Pro is ideal for designers of PCBs, microwave circuits, RF circuits and IC packages where closed boundaries are essential for conversion to mask data. It most cases the DXF output of the AutoCAD drawing will be converted either to Gerber or GDSII format - both of which require closed polyines to convert the outline data to commands for the mask making machine.

Manual Price List Revision History Download