[postgis-devel] [PostGIS] #314: Geographic point-in-polygon issue: stab line grazes vertex

[PostGIS]

#314: Geographic point-in-polygon issue: stab line grazes vertex
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  Reporter:  pramsey  |       Owner:  pramsey      
      Type:  defect   |      Status:  new          
  Priority:  medium   |   Milestone:  PostGIS 2.0.0
 Component:  postgis  |     Version:  trunk        
Resolution:           |    Keywords:               
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Old description:

> While fixing the co-linear case I was reminded of another unhandled case.
> If the stab line grazes a vertex but does not actually cross, a crossing
> will still be counted.
>
> http://trac.osgeo.org/postgis/browser/trunk/liblwgeom/cunit/cu_geodetic.c#L628
>
> We could detect the condition and abort by running every test twice, with
> different stab lines.

New description:

 While fixing the co-linear case (#255) I was reminded of another unhandled
 case. If the stab line grazes a vertex but does not actually cross, a
 crossing will still be counted.

 http://trac.osgeo.org/postgis/browser/trunk/liblwgeom/cunit/cu_geodetic.c#L628

 We could detect the condition and abort by running every test twice, with
 different stab lines.

-- 
Ticket URL: <http://trac.osgeo.org/postgis/ticket/314#comment:1>
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