Fun Stuff: Computing circular buffers in geographic coordinates
Finding all the objects within a certain distance from a point is surely a common GIS problem. The problem is normally solved using OGC "dwithin" filters or by computing a buffer and then finding all the intersecting objects. Very often both of the approaches fail miserably in case the coordinate system is a geographic one, as common libraries, such as JTS and GEOS, are not able to handle the non planar nature of it. As far as "dwithin" is concerned rencent Oracle and PostGIS versions can manage the problem properly, but what to do if they cannot be used?We had...
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