topic Re: How to simplify polyline in AutoCAD Forum

How to simplify polyline

Anonymous — Wed, 27 Mar 2019 16:09:36 GMT

Hello!

I have a problem with too many vertices on a 2d object. I want to lower down the number of vertices but still keep approximately the same shape.

File in the attachment

Re: How to simplify polyline

Patchy — Wed, 27 Mar 2019 16:17:19 GMT

This will do

http://cadtips.cadalyst.com/linear-objects/polyline-diet

Re: How to simplify polyline

Kent1Cooper — Wed, 27 Mar 2019 17:00:10 GMT

@Patchy wrote:

This will do

http://cadtips.cadalyst.com/linear-objects/polyline-diet

Thanks for the recommendation [that's my PLDIET.lsp routine]. The PLD command there does this to that shape, given a maximum distance to straighten of 50 and accepting defaults for the rest, reducing it from 368 vertices to 82:

If that turns out kinkier than you want in areas of tigher curvature, use a smaller number than 50.

Re: How to simplify polyline

Anonymous — Wed, 27 Mar 2019 17:30:24 GMT

Thanks!

This really did the job and you can also decide how detailed is your object gonna be

Re: How to simplify polyline

Kent1Cooper — Wed, 30 Oct 2019 16:51:40 GMT

@Patchy wrote:

This will do ....

... updated version >here<.

Re: How to simplify polyline

cgh6VFSY — Tue, 12 Mar 2024 14:34:19 GMT

The link above is dead and the second link only takes me to the autodesk forum. Given how slow autocad is with polylines/splines it would be great if this could get sorted in one single software rather than fixing it elsewhere and import it back in.

Re: How to simplify polyline

pendean — Tue, 12 Mar 2024 15:07:56 GMT

@cgh6VFSY wrote:

The link above is dead and the second link only takes me to the autodesk forum. Given how slow autocad is with polylines/splines it would be great if this could get sorted in one single software rather than fixing it elsewhere and import it back in.

https://cadtips.cadalyst.com/linear-objects/polyline-diet

https://forums.autodesk.com/t5/autocad-forum/reduce-polyline-points/m-p/8520844#M963796

Re: How to simplify polyline

Kent1Cooper — Tue, 12 Mar 2024 19:25:41 GMT

Cadalyst CAD Tips are currently not downloadable, and I've told them about it, and they say they're working on it. I don't know why the other link doesn't go to a specific message, other than the vagaries of the passage of time, but in any case, here's the routine.

Re: How to simplify polyline

pascal — Fri, 15 Mar 2024 02:53:31 GMT

does PLDiet work on 3DPolylines in AutocadLt? I'm struggling with a survey plan that is way too detailed to import into sketchup

Re: How to simplify polyline

pascal — Fri, 15 Mar 2024 03:03:24 GMT

sorry finally found a super simple solution from these guys.. you just have to sign up but it's free and it worked instantly.

https://esurveying.net/free-lisp/reduce-polyline-vertices

Re: How to simplify polyline

Amanda_Deng — Thu, 06 Nov 2025 19:59:48 GMT

I downloaded the polyline problem dwg file and went through the prompts. How come after I select all points it was not doing anything?

Re: How to simplify polyline

Amanda_Deng — Thu, 06 Nov 2025 20:21:11 GMT

was trying to run this file with the LSP below. Please let me know if the LSP works for you... and give me some pointer why mine does not.... thanks in advance!

Re: How to simplify polyline

Kent1Cooper — Thu, 06 Nov 2025 21:23:04 GMT

@Amanda_Deng wrote:

.... give me some pointer why mine does not....

Maybe it doesn't work because:

1. the arguments fed into the CONVERT command for a 2D Polyline do not follow the prompt sequence in the command; and/or

2. there is no NumberOfVertices property for a Polyline [either lightweight or heavy]. Where did this code come from? It would be symptomatic of Artificial Intelligence to assume such a non-existent property.