AutoCAD Break Between Two Lines LISP: Cut Many Lines at Once

Removes the segment between two cutting lines from all the lines you select, in one pass.

This AutoCAD LISP adds the BRKBETWEEN command, which removes the part of each selected line that lies between two cutting lines. It is handy for opening a door, a passage or a section gap through a bundle of parallel lines.

The cutting lines don't have to physically reach the lines being cut; the tool treats each cutter as an infinite line in its direction. A line is cut only when both intersection points fall on that line, so a line that reaches only one cutter is left as it is.

AutoCAD's BREAK command also removes the part between two points, but you have to give the points for each object separately. TRIM can use the two lines as cutting edges, but you still click every segment to remove. BRKBETWEEN does the whole selection in one command.

How to use it

1. Load brkbetween.lsp with APPLOAD and type BRKBETWEEN.
2. Pick the first cutting line.
3. Pick the second cutting line.
4. Select the lines to cut and press Enter; the segments in between are removed and the count is reported.

Notes and tips

• Both the cutting lines and the lines to cut must be LINE objects; polylines and arcs are not supported.
• If the cutting lines end up in the selection, they are skipped and not cut.
• Lines parallel to a cutting line have no intersection with it, so they are not cut.

Frequently asked questions