CGAL users discussion list

[lloyd <>]

Hi Laurent

Thanks for the clarification.

I was starting to guess that they must be split. I started implementing it via line circle intersections, where the circle area is at the end point of an(other) edge. Snapping allows merging the lines with a tolerance.

Bryn

Von Samsung Mobile gesendet

-------- Original message --------
From: "Laurent Rineau (CGAL/GeometryFactory)"  
Date:25/08/2015  21:23  (GMT+01:00) 
To:  
Subject: Re: [cgal-discuss] Merge polylines 

Le lundi 24 août 2015 14:05:05 Bryn Lloyd a écrit :
> Dear Sebastien
> 
> I attached the surface and polylines as code sample (C-arrays), but can
> also provide other formats if that is easier for you.
> 
> Thanks & best regards

Hi Bryn,

I know what is wrong in that input data.

At the points (29, -39, 0), (29, -39, 18), there are two line segments that 
pass through those points in their interior. You must split those two line 
segments so that in the end the polylines (here, only line segments) only 
intersect at their extremities.

Otherwise, the polylines appear as non-adjacent combinatorially, whereas they 
intersect geometrically. And the 1D mesher of CGAL Mesh_3 tries to separate 
the non-adjacent polylines, and cannot do that because they cannot be 
separated geometrically.

-- 
Laurent Rineau, PhD
R&D Engineer at GeometryFactory           http://www.geometryfactory.com/
Release Manager of the CGAL Project       http://www.cgal.org/


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