"TryGetArc" limitations?

Scripting
1

I’m extracting isocurves from piped surfaces that I know should be exactly or well approximated to round in at least 1 direction and it’s not working well at all. Could there quirks to the nature of the surfaces, not sure how they were made or how many times they were round-tripped through DWG file, that might cause it to fail to find what I think are obvious arcs? It’s probably some other sort of bug in my code but just wondering…

2

I dont think you get arcs from piped surface.
Make a arc , than a pipe from it to extract a isocurve and see what happen.

3

Can you post an example?

4

I’m thinking it’s just my logic…

5

Dunno, this seems to work with a couple of perpendicular sections through pipes:

import rhinoscriptsyntax as rs
import scriptcontext as sc
import Rhino

obj_id=rs.GetObject("Select section curve",4,preselect=True)
if obj_id:
    tol=sc.doc.ModelAbsoluteTolerance
    crv=rs.coercegeometry(obj_id)
    print type(crv)
    rc,result=crv.TryGetArc(tol)
    print type(result)

Returns:

<type 'NurbsCurve'>
<type 'Arc'>

Even if I don’t supply the optional tolerance argument it seems to succeed.

6

Thanks Mitch!