[Gdal-dev] using OGRLayer::SetSpatialFilter to access polygons in .shp files

[Amanda Tucker]

Hello, 

 

My goal is to input a point (lat/long) and to get all polygons that
contain this point.  I am using SetSpatialFilter() to filter on the
specified point.  I am being returned correct features (polygons), but
often, I am getting extra polygons.  I can see through GUI tools that
some polygons/multipolygons are being returned that do not contain the
point.  The doc for SetSpatialFilter() states 'currently this test may
be inaccurately implemented'.  Are there known cases that this method is
inaccurate?  And is this one of those cases?  Is there another way to
get the results I desire?  I also tried using within()/contain() after
these polygons were returned, but that did not work because I am not
building with GEOS.  Is there any way I can get the correct results
without building with GEOS?  And if not, where do I find the GEOS
binaries/source code to build with OGR?  And will these methods in GEOS
even solve my problem?

 

Thanks, Amanda

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