CGAL users discussion list

[Siddharth Gupta <>]

Hi

I did in a bit different manner. I computed all the intersection points and checked it against each segment to group the segments. I didn't get why the function which did this was there in version 3.x but got it removed from later versions.

I have attached my code for the same.

 

On Thu, Apr 28, 2016 at 7:27 PM, Юрий Дынников <> wrote:

Hello, Siddharth

Take a look at http://doc.cgal.org/latest/Sweep_line_2/group__PkgIntersectionOfCurves2.html .

Your task could be achieved by following: 

1. Prepare all segments, give them IDs (you should use Arr_curve_data_traits_2 for that, but I had problem with it)

2. compute_subcurves will give you subsegments, each subsegment should have ID of parent segment

3. For each subsegment you can get its start and end vertices -> you can create cross-table of vertices and parent segments

4. Analyze, which segments intersect in each point

If you will get it working, please share your code with me, as I haven't yet understood how to implement such thing with Arr_curve_data_traits_2 (the question was previously on the list, but I didn't find time to make minimal example yet) 

пт, 29 апр. 2016 г. в 2:12, Siddharth Gupta <>:

In newer version of CGAL, given a set of line segments, we can't find out the set of lines interesting at a point. I am checking them pairwise using do_intersect() but it's very slow. Can someone suggest me a better way?

My goal is to to find out all pairs of intersecting segments in a give set of line segments.

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Siddharth Gupta

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Siddharth Gupta

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