Segmented Circle,Arc and Ellipse Convert to Non-Segmented Object

[Anonymous]

I have imported a dwg file from Sketchup, the problem is Arc, Circle and Curved lines are Segmented, I would like to convert it to non-segmented drawing so it is easy for me to put radius and snap to the right vertices. I found the right LSP for the circle but not for the arc and ellipse, when I tried it on the arc it will create a circle. 

Is there a way to convert this?? Thanks.

[Kent1Cooper]

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@Anonymous wrote:

.... Arc, Circle and Curved lines are Segmented, I would like to convert it to non-segmented drawing .... I found the right LSP for the circle but not for the arc and ellipse....

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That's one of mine.  Here's a modification for the Arc variety [untested]:

(defun C:PS2A (/ ss n pl pars); = Polyline{s} of Segments {to} Arc{s}
  (prompt "\nTo draw true Arcs over mult-segment Polylines approximating arcs,")
  (setq ss (ssget "_:L" '((0 . "*POLYLINE"))))
  (repeat (setq n (sslength ss))
    (setq
      pl (ssname ss (setq n (1- n)))
      pars (vlax-curve-getEndParam pl); number of PARameterS
    ); setq
    (command "_.arc"
      "_none" (vlax-curve-getStartPoint pl)
      "_none" (vlax-curve-getPointAtParam pl (/ pars 2))
      "_none" (vlax-curve-getEndPoint pl)
    ); command
    (entdel pl); remove original [optional]
  ); repeat
); defun

You would need to select the ones that are Arc-like.  As with the Circle variety, it will draw an Arc between the start, somewhere in the middle, and the end, of any selected Polyline(s) of any shape.  [The circle one likewise, which you have already discovered.]  Something could be made that could determine arc-likeness, and do it to only those that qualify, but that would be quite a bit more complex.

For the Ellipse, what range of possibilities are there?  I can imagine a way to do it if they're always and only half-Ellipses between ends of the same axis, as in your image.  If not, I'm having a hard time picturing how a routine would be able to figure out the axis endpoints, which it will need to draw a true Ellipse.

[Anonymous]

Thank you so much it works in a segmented arc and big help, but I don't think it will work on an ellipse, I'm a fan and user of your lisp. and it makes my work easier.