[gdal-dev] Esri JSON Curves

[Even Rouault]

> This would still be an issue with paging.  Most of the actual datasets
> of interest (to me) involve multiple HTTP requests to fetch many pages
> of JSON data (usually 1000 - 10000 features at a time depending on
> server setup).  The curves may easily not be on the first page and
> re-running the whole request is expensive.

Fair enough

> > If my memories are right, you only need to set it for write support. So
> > shouldn't be needed there.
> 
> All I know is that without it set, the curved geometries were linearized
> somewhere in OGR before they were passed to the PostGIS driver.

You should double check and spot where this comes from.
You can set a breakpoint on OGRGeometryFactory::curveToLineString which should 
be taken when linearization occurs.

As an experience, I've disabled OLCCurveGeometries and ODsCCurveGeometries 
capability declaration in the CSV driver, and no linearization occurs when 
converting to PostGIS

Even

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