[FWTools] Python object serialization (pickle) of OGRGeometry

Jack L. Riley Jack.Riley at noaa.gov
Mon Feb 12 13:07:43 EST 2007

Hello Frank et al,

I have a Python (v2.3.5-based) application which stores OGR feature 
geometry objects (<OGRFeature>.GetGeometryRef().Clone()) in a dict.  To 
support pickling of these OGRGeometry instances (w/o spatial reference 
system), I added the following __getstate__ and __setstate__ methods to 

   def __getstate__(self):
       return self.ExportToWkb()
   def __setstate__(self, state):
       result = CreateGeometryFromWkb(state)
       self._o = result._o
       self.thisown = result.thisown
       result.thisown = 0

Note that a similar thing was done in Python Cartographic Library's 
geometry.py--see trac changeset 411:

Might this be included in future releases of FWTools/ogr.py (read: would 
this be wise, or am I overlooking something)?

Best regards,

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