FREE AUTOCAD LISP

IRRLINE — the irrigation line that follows your plot border, curves included

Select the plot, pick where the line starts and ends, type the offset — and IRRLINE draws the sub-main or lateral parallel to the plot border, following straight runs and curves alike.

Select two touching plots and they merge automatically: the line follows the outer border and ignores the shared edge, so start in one polygon and end in the other. Before accepting, F flips the direction around the border and S switches the side between inside and outside.

How to use it

1. Unzip, then load the .lsp with APPLOAD.
2. Type IRRLINE.
3. Select the plot polygon – or two that share an edge.
4. Pick the START and END points, type the offset distance (the last one is remembered).
5. F to flip, S to switch inside/outside, Enter to accept.

Good to know

Take it further — measure and split areas automatically

Divide Area Split any closed shape into pieces of equal area – by number, by distance, a set area or a free cut. See Divide Area — $21.90

Area Measure Measure closed shapes in any unit, number them, and get a totalled area table – annotative text supported. See Area Measure — $21.90

Voronoi Generator Fill any closed polyline with Voronoi cells – exact spacing, edge distance and rounding, live preview. See Voronoi Generator — $24.90

This tool is part of our free AutoCAD LISP collection — 20+ routines, all free, all tested on real projects.