CGAL users discussion list

[Marcos Dione <>]

On Wed, Aug 31, 2016 at 09:57:05AM +0200, Sebastien Loriot (GeometryFactory) 
wrote:
> Right, I had a issue with my path.
> I checked again and the polygon is valid.
> However, I could call create_interior_straight_skeleton and
> create_exterior_straight_skeleton_2 with no error.
> 
> I looked at the sfcgal code to use the exact same calls they were doing
> and I had no issue.
> 
> You can try it yourself:
> 
> https://gist.github.com/sloriot/29b613a7180f43ec01827fe70d095dca

    Here's what I get on my end:

In [1]: import shapely.wkt

In [2]: s= open('121897178.wkt').read()

In [3]: sh= shapely.wkt.loads(s)       

In [4]: import psycopg2

In [7]: conn= psycopg2.connect(dbname='gis')

In [8]: import centerlines

In [10]: centerlines.skeleton_medials_from_postgis (conn, sh)
---------------------------------------------------------------------------
InternalError                             Traceback (most recent call last)
<ipython-input-10-d5ff10333f12> in <module>()
----> 1 centerlines.skeleton_medials_from_postgis (conn, sh)

/home/mdione/src/projects/osm/osm-centerlines/centerlines/__init__.py in 
skeleton_medials_from_postgis(connection, way)
    122     cursor= connection.cursor ()
    123     cursor.execute ("SELECT ST_StraightSkeleton(%s), 
ST_ApproximateMedialAxis(%s);",
--> 124                     (way, way))
    125     skel, medials= [ decode (i) for i in (cursor.fetchone ()) ]
    126

InternalError: CGAL failed to create straightSkeleton

    I'll try to figure out where this is comming from. Thanks for you
time so far. Cheers,

        -- Marcos.

--
PS: centerlines.skeleton_medials_from_postgis() is this Python function: 
https://github.com/StyXman/osm-centerlines/blob/master/centerlines/__init__.py#L117

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