topic Re: break a line to N numbers of segments in AutoCAD Forum

break a line to N numbers of segments

Anonymous — Wed, 24 Dec 2014 08:56:58 GMT

Dear all,

This is vykunta my question is here How to convert my line to N number of segments line?

Re: break a line to N numbers of segments

Alfred.NESWADBA — Wed, 24 Dec 2014 09:17:09 GMT

Hi,

there is no standard function for that within plain AutoCAD 2015, but if you have a vertical product like ACA, MEP, Civil 3D ... you might have such a functionality built in, in that case let's know what product you have.

The other option is to search the www. If my remembering is ok then there are exists some LISP's doing that.

- alfred -

Re: break a line to N numbers of segments

Kent1Cooper — Wed, 24 Dec 2014 13:33:30 GMT

@Anonymous wrote:

....How to convert my line to N number of segments line?

You can use the SD command in the SubDivide.lsp file attached. That will break it into segments that touch at their ends.

If you want it broken up into pieces with gaps between them, i.e. to look like a non-continuous linetype such as HIDDEN, use the BreakUp.lsp file attached. The command names are BU- followed by the linetype name, such as BU-HIDDEN. It's in progress -- read the comments at the top. It won't let you specify the number of segments, but bases its breaking up on the linetype definition and the drawing's current linetype scale, so if you want a specific number of segments, you'll need to try it at different LTSCALE settings until the result is right.

Re: break a line to N numbers of segments

Kent1Cooper — Thu, 06 Oct 2022 15:34:27 GMT

Updated version of SubDivide.lsp that allows selection of multiple objects, all to be SubDivided in the same way.

Re: break a line to N numbers of segments

silvia_aldrighetti_1 — Thu, 13 Jul 2023 15:10:15 GMT

Hello everyone, I have a question about the LISP SubDivide.

I noticed that the actual lengths of the segments it creates from the selected line are never of the length that I input with "M", but always slightly less. I was wondering if there is a way (or another LISP) that allows to create the various segments of the lenght I choose. I am still a beginner so I am not aware of anything similar.

Thanks!

Silvia

Re: break a line to N numbers of segments

Kent1Cooper — Thu, 13 Jul 2023 15:26:15 GMT

@silvia_aldrighetti_1 wrote:

.... the actual lengths of the segments it creates from the selected line are never of the length that I input with "M", but always slightly less. I was wondering if there is a way (or another LISP) that allows to create the various segments of the lenght I choose. ....

That's what the M stands for - Maximum, meaning "break this into the smallest number of equal-length pieces such that their length does not exceed the Maximum I specified." It's a Maximum, not a fixed length. Of course, they're not always slightly less, but will be whenever the overall length is not a clean multiple of the Maximum length specified. And they could be more than slightly less, depending on the relationship of current length to Maximum. [For instance, if you use it on a 10-unit-long object, and specify a Maximum segment length of 9 units, the result will be two pieces of only 5 units, because it has to do two pieces or the result would exceed the Maximum.]

It's designed for equal-length results. If you want a specific length rather than a Maximum, except when the overall length is a clean multiple of that you will get all but one segment at that specific length, and one shorter, with how much shorter varying all over the map. Is that what you want? That could be done, but there's also the question of whether you would care at which end the shorter resulting segment falls.

Re: break a line to N numbers of segments

silvia_aldrighetti_1 — Thu, 13 Jul 2023 16:43:33 GMT

Thanks for the quick reply!

Yes exactly, I would like to obtain a specific-length result and I don't really care at which end the shorter segment would be. Could it be possible?

Silvia

Re: break a line to N numbers of segments

Kent1Cooper — Thu, 13 Jul 2023 18:50:04 GMT

The attached MeasureBreak.lsp [a modification/simplification from SubDivide.lsp] with its MB command seems to do that in limited testing. See the comments at the top of the file.

Re: break a line to N numbers of segments

silvia_aldrighetti_1 — Fri, 14 Jul 2023 09:02:54 GMT

I checked it and it seems to work! Thank you really much for the help!

Silvia

Re: break a line to N numbers of segments

90491929 — Mon, 04 Sep 2023 14:59:27 GMT

Thanks @Kent1Cooper,

I found an issue with this 3d polyline.

Is this meant to work with 3d polys? I see there's a *polyline in the ssget.

Re: break a line to N numbers of segments

Kent1Cooper — Mon, 04 Sep 2023 16:36:36 GMT

@90491929 wrote:

.... I found an issue with this 3d polyline. Is this meant to work with 3d polys? I see there's a *polyline in the ssget.

What is your "issue"? Assuming you're talking about the SD command in SubDivide.lsp, yes, it works with 3D Polylines. See the comment at the top: "Works on anything that Break can be used on...." I just tried it on yours, successfully. [It's planar -- is there some reason for it to be a 3D Polyline instead of one of the 2D kinds?] If it doesn't work for you, what happens instead?

The * is a wildcard standing for any character content [including nothing], in this case to allow both LWPOLYLINE and POLYLINE as entity types to be accepted. [POLYLINE covers both 3D and "heavy" 2D varieties.] It could have used just *LINE to cover LINE, POLYLINE, LWPOLYLINE and SPLINE all in one entry, but that would also allow XLINE and MLINE, which are not allowable [XLINE because they don't have length to divide, and MLINE because BREAK can't work on them].

Re: break a line to N numbers of segments

CAD7875 — Fri, 08 Sep 2023 09:01:49 GMT

jumping on this thread as i was looking for something similar.... is there a lisp or command whereby you could set the distance between points along a line, but from the centre? i'll try and explain; if i wanted to set points at 1000mm, the middle 1000 line would be on the centre of the original line and then there would be 2 equal shorter distances at either end of the original line...

Re: break a line to N numbers of segments

Kent1Cooper — Fri, 08 Sep 2023 10:17:46 GMT

@CAD7875 wrote:

.... is there a lisp or command whereby you could set the distance between points along a line, but from the centre? i'll try and explain; if i wanted to set points at 1000mm, the middle 1000 line would be on the centre of the original line and then there would be 2 equal shorter distances at either end of the original line...

Try DivideMeasurePlus.lsp, >here<. Its MEA+ command has an option to center the Points [or Blocks, or Line markers, or selected object(s)] on the path object(s). It does have the one difference that depending on the relationship between spacing and object length, it will sometimes place a Point [or whatever] at the midpoint, rather than have the middle of a segment there. It could probably be modified to always do it as you describe. And it puts things -- it doesn't break the path object into pieces -- but again, it could be modified to do the latter.

Re: break a line to N numbers of segments

CAD7875 — Fri, 08 Sep 2023 11:17:14 GMT

Works an absolute treat! thank you 🙂