AutoLISP Routines

THREAD draws a 60° V thread along a centreline you specify — the detailed representation, with the actual crests and roots, rather than the two parallel lines of the simplified convention. What ScrewThread does For a drawing where the thread form matters: a detail of a screw, a tapped hole in section, a leadscrew, or anything being made from the drawing … [Read more...] about THREAD LISP: Draw a 60-Degree Screw Thread in Section

ROOFPITCH draws the little right-angled triangle that marks a roof slope, with the rise and the run written on it — 4 over 12, 1 over 40, whatever the roof is. The triangle can face any of the four ways, so it sits correctly whichever slope it is labelling. What RoofPitch does It will also read the slope off the drawing. Pick two points along the roof line … [Read more...] about ROOFPITCH LISP: Draw a Roof Pitch Triangle in AutoCAD

Pick a polyline and get a road or a railway built along it. ROAD draws kerbs or shoulders either side at a width you give, and can add a centre line down the middle. RAILWAY draws two rails and lays sleepers across them at a spacing, each one square to the track at that point. What RoadLines does Both follow curves properly, because both work from the curve itself … [Read more...] about ROAD and RAILWAY LISP: Roads and Track from a Centreline

BLOCKRENAME renames many blocks in one go, from a two-column file of old and new names. For bringing a drawing onto the office standard, or for tidying up after a consultant whose block names mean nothing to anyone else. What BlockRename does The file is plain text, one pair per line, comma … [Read more...] about BLOCKRENAME LISP: Rename Blocks in Bulk from a List

POLY3D converts a flat polyline into a 3D polyline, so its vertices can be given individual heights. POLYFLAT goes the other way, dropping a 3D polyline back to one level. What PolyTo3D does A contour traced flat can be lifted to its level. A drainage run can be given falls. A road centreline can take a vertical alignment. None of that is possible while it is a … [Read more...] about POLY3D LISP: Lift a Flat Polyline Into Three Dimensions

PTIMPORT reads a text file of coordinates and builds geometry from it — survey points from a total station, setting-out data, a traverse, a profile, or anything else that arrives as columns of numbers. What PointImport does It will make POINT objects, a chain of lines, a polyline, a 3D polyline, a block at each coordinate, or a copy of anything you … [Read more...] about PTIMPORT LISP: Import a Coordinate File Into AutoCAD