AutoLISP Routines

FLRJOIST draws an I-section as real surfaces — a timber I-joist with its flanges and web, or a steel beam — lying along the X axis from a point you pick. What FloorJoist does Useful for a 3D framing model, for checking clearances against ductwork and services, and for cutting a section anywhere along it. What it is made of: twelve 3D faces … [Read more...] about FLRJOIST LISP: Draw an I-Joist or Steel Beam in 3D

FLEXDUCT draws flexible ductwork along a route you pick — two walls at the duct width, with the corrugated coil between them that says flexible on an HVAC drawing, and a plain collar at each end where it clamps to rigid. What FlexDuct does It follows a run of straight legs, rounding each corner to a bend radius, so a drop from a branch to a diffuser takes a … [Read more...] about FLEXDUCT LISP: Draw Flexible Ductwork Along a Route

Draw a fence across a drawing and every object it crosses is cut at the crossing point. Nothing is erased and nothing moves — objects are simply split in two where the fence passes through them. What FenceCut does This is the operation you want before deleting half a plan, before moving a section of a site layout, or before putting a match line through a … [Read more...] about FENCECUT LISP: Split Everything That Crosses a Fence

FACEHOLE cuts a window or door opening in a wall built from 3D faces. Pick the face, pick two corners for the opening, and the face is replaced by four faces that surround the hole — so the wall still reads as solid, still hides what is behind it, and still shades, but now has a hole in it. What FaceHole does Meant to go with HOUSESHELL, which builds the … [Read more...] about FACEHOLE LISP: Punch an Opening Through a 3D Face

DIMNOTE adds one of the stock abbreviations — TYP., CLR., V.I.F. and the rest — to a dimension, either alongside the figure or on a second line under it. Typing them by hand is how you end up with TYP, TYP. and Typ. in the same drawing. What DimNote does DIMFLIP turns a dimension round so it measures from the other end — useful when the arrows … [Read more...] about DIMNOTE LISP: Add Standard Notes to AutoCAD Dimensions

When a dimension is taken to the centre of something — a hole, a column, a pipe, a road — the extension line on that side ought to be drawn as a centreline, not a continuous line. AutoCAD has no setting for it: extension lines take the dimension’s linetype and that is that. What DimCentre does DIMCENTRE suppresses the extension line and draws a … [Read more...] about DIMCENTRE LISP: Draw an Extension Line as a Centreline