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# How to convert an ellipse to a polyline in CAD?

Jenny

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Registered: 2013-5-6

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How to convert an ellipse to a polyline in CAD?
31-05-2013 11:26 . am | View his/her posts only
CAD users might encounter the following situation while they are using ZWCAD: They need to edit the ellipse object like polyline, but the properties of ellipse are not like the properties of polyline. So how can we do this if we want to join an ellipse arc, line and other objects into polyline? In the following content, we will give you a brief introduction on how to convert an ellipse to a polyline in CAD.

Approach 1: Open ZWCAD, and then set PELLIPSE to 1 (or ON)
The PELLIPSE System Variable is used to controls whether the entity drawn with the ELLIPSE command is a true ellipse or an ellipse made up of polylines.
0 Draws a true ellipse.
1 Creates an ellipse made up of polylines.

PELLIPSE =0

PELLIPSE =value 1

Approach 2: offset the ellipse object
After an elliptical arc is created, we can use Offset command to change it to polyline. Offset the elliptical arc to a certain distance, and then delete the original elliptical object, after that run offset command again to offset the elliptical arc back to original position, by this way, the elliptical arc is changed to SPline object.
Then we can use command Flatten to change the SPline to Polyline, and use command Pedit to join the polylines.
Both two approach are quite easy to convert the ellipse to a polyline.

You might be also interested in these posts:
Use PEDIT to make a Line a Polyline
Use lisp to convert line to polyline.
Extrude 3D Polyline
How to measure area enclosed by a polyline?

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