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Reference

SPLINEDIT in AutoCAD

How AutoCAD's SPLINEDIT (SPE) works: Close, Join, Fit data, Edit vertex, convert to Polyline and Reverse, prompt by prompt. Try it free in your browser.

SPLINEDIT edits a spline. Pick one at Select spline:, or select it before the command; double-clicking a spline runs SPLINEDIT on it too. Anything else says Object selected is not a spline. and asks again; a polyline fitted by PEDIT's Spline is turned into a spline of the same curve, without a word. Then it asks for an option again and again, each applied at once, until EXit or Enter. The spline shows its fit points' grips, and while you edit its vertices, its control vertices and frame. The whole edit is one step that U takes back. Typed 'ZOOM works at any of its prompts.

At the command line

The engine draws it and writes its history as you would type it: the prompts in AutoCAD 2027's order, with the same option letters.

A spline through five fit points, closed by SPLINEDIT: a smooth loop through them all.
  1. Command: SPLINEDIT
  2. Select spline:
  3. Enter an option [Close/Join/Fit data/Edit vertex/convert to Polyline/Reverse/Undo/eXit] <eXit>: C
  4. Enter an option [Open/Fit data/Edit vertex/convert to Polyline/Reverse/Undo/eXit] <eXit>:
A spline through five fit points, closed by SPLINEDIT: a smooth loop through them all.

Options

Close (C)

Closes the spline smoothly: a fit spline through its fit points, a CV spline on its vertices. On a closed spline the option is Open, and Join is not offered.

Join (J)

Joins open curves that meet its ends, by JOIN's rules for a spline, and says how many it joined.

Fit data (F)

Edits the points the spline passes through. A CV spline, which has none, is first given fit points on its curve. Its options: Add picks a fit point and adds new ones after it, again and again (at an open spline's first point, After or Before); Delete removes fit points, down to two, three on a closed spline (Cannot delete beyond this.); Move steps through the fit points with Next and Previous, or Select, and moves the current one to the point you give; Purge drops the fit data, leaving a CV spline; Tangents sets the start and end directions, or System; Close and EXit as at the first prompt. A pick that is no fit point says Not a fit point..

Edit vertex (E)

Edits the control vertices; a fit spline loses its fit data at the first edit. Add puts a vertex at the point you pick on the spline; Delete removes one, down to two, three on a closed spline; Elevate raises the order, up to 26, never down; Move moves vertices, stepping as Fit data's Move does; Weight sets a vertex's weight, after Spline is not rational. Will make it so., so the curve pulls nearer to it or further away. A pick that is no vertex says Not a control vertex..

convert to Polyline (P)

Asks a precision from 0 to 99, 10 by default, and replaces the spline with a polyline of straight segments, more of them the higher the precision; a 3D polyline where the spline does not lie flat, parallel to the XY plane. It ends the command. The precision is kept for the session, and PEDIT's conversion uses it too.

Reverse (RE)

Turns the spline round, its first point last: Spline has been reversed..

Undo (U)

Takes back the last option, a whole Fit data or Edit vertex at once. With none left: Command has been completely undone..

eXit (EX)

Ends the command, as Enter does.

What it does not do yet

Kink, which puts a sharp corner at a fit point or vertex; toLerance, which refits the spline within a tolerance; Tangents of a closed spline. convert to Polyline makes far more vertices of a fit spline than AutoCAD does, never arcs, and always replaces the spline. Group at Select spline:. The + AutoCAD draws on the current point while you step through the points.

What it does and still lacks, in detail (in English)

Questions

What is the shortcut for SPLINEDIT in AutoCAD?

SPE, then Enter or Space. The full name works too, and _SPLINEDIT in any language of AutoCAD. Double-clicking a spline also runs it.

How do I convert a spline to a polyline?

Run SPLINEDIT, pick the spline and choose Polyline; a precision of 10 gives a smooth polyline. PEDIT on a spline offers to convert it too.

How do I add or move points on a spline?

Choose Fit to work on the points it passes through, then Add or Move. Choose Edit to work on the control vertices that frame it.

How do I close a spline?

Choose Close: it closes smoothly, without a corner where it meets itself. Open opens it again.

How do I join two splines?

Choose Join and select the spline whose end meets this one's, or use JOIN.

Related commands