AutoCAD Civil 3D General Discussion

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Posts: 33
Registered: ‎07-09-2013
Message 1 of 4 (223 Views)
Accepted Solution

Extracting polylines from a corridor

223 Views, 3 Replies
02-17-2014 02:32 PM

I am trying to create a "proposed work" file that is a 2d file, basically a birds eye view of my corridor.  I have a corridor and I am trying to extract polylines from it.  I can get as far as extracting the lines and making them into polylines.  My problem is that the polylines are one line running the length of the corridor, then when I explode them they become very small line segments.  I would like a tangent line, followed by a curve, then a tangent, and so on (similar to how an alignment is broken up).


Can anyone help me with this?

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Message 2 of 4 (216 Views)

Re: Extracting polylines from a corridor

02-17-2014 02:44 PM in reply to: ashleystrand

Guessing you may know that Corridors can't display curves so if on a curve, what you're trying to accomplish

might not be so easy.

Offsetting the alignment or alignments using a simple AutoCad OFFSET command may provide more desirable

polylines to create a 2d file.


Extra vertices in Polylines can be cleaned up by using the MAPCLEAN command.


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Posts: 356
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Message 3 of 4 (207 Views)

Re: Extracting polylines from a corridor

02-17-2014 03:07 PM in reply to: ashleystrand

I believe that C3D draws each feature line as straight lines between frequency lines. So thats why when you extract it, it is not a curve, just a polyline with a bunch of vertices. You may have to free hand the curve portions.


If these lines are to be used for 2D purposes only, why not simply offset the Alignment to either side however many offsets you need, and use those? That will generate a smooth linetype such as what you're seeking.



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Message 4 of 4 (168 Views)

Re: Extracting polylines from a corridor

02-18-2014 12:47 AM in reply to: ashleystrand

I'd agree with the comments about offsetting the alignment but you can use the vanilla AutoCAD JOin command to join all the line segments back together again quite easily......and this will be a 3D polyline

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