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[Sukhraj Singh <>]

Thanks for your answer, Sebastien

Do I really need to use connected_components()

I already have the "segment_pmap", where the value is the segment id to which that particular face belongs.

And one could parse the Polyhedron and collect all the faces having particular segment ID.(Of-course I need to check, how to implement the same)

Is my understanding correct ?

Further, quoting from my previous email:

Two spatially apart areas( i.e. not having
common edges) of a Mesh may fall into same segment, since they had
comparable SDF values.

I am not sure about it, they of-course may fall into same cluster, but may not be to the same segment.  In such a case if, faces that don't share edge, will fall into different segment always, even though they were in same cluster, using connected_components() may not be required ?

On Thu, May 12, 2016 at 6:00 PM, Sebastien Loriot (GeometryFactory) <> wrote:

On 05/12/2016 02:16 PM, Sukhraj Singh wrote:

Salut,

The "Triangulated Surface Mesh Segmentation" module allows one to
segment a surface mesh using the SDF values.
It creates a Property Map which is colorized according to the indices,
resulting into segments. Two spatially apart areas( i.e. not having
common edges) of a Mesh may fall into same segment, since they had
comparable SDF values.

My question is, how can one extract these segments. Since I want to do
further processing on a segment separately. Also I would like further
divide a segment, into say sub-segments , where a sub-segment will have
faces which are not spatially apart, i.e.  a subset which is having
common edges only.

Set the parameter output_cluster_ids to true when calling the
segmentation function

http://doc.cgal.org/latest/Surface_mesh_segmentation/group__PkgSurfaceSegmentation.html#ga8533ea7b1062ebbabe3bf23fed303f24

If you need also the segments, then set the option to false and
use the function connected_components() considering as constrained
edges the edges between two faces belonging to different
segments.

http://doc.cgal.org/latest/Polygon_mesh_processing/group__keep__connected__components__grp.html#gabe2052b2281e1e628e68d8fea94be2d9


Sebastien.

Thanks to inform.




P.S. I am a newbie.
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Sukhraj Singh

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Sukhraj Singh