[Qgis-developer] GEOS geometry from QgsGeometry with the Python API?

[Sandro Santilli]

On Wed, Apr 18, 2012 at 12:06:31AM +0200, G. Allegri wrote:

> > Right, it would need some kung-fu across QGIS-GEOS python bindings. It
> > was never really a top priority for me since QgsGeometry exposes the
> > most important GEOS geometry algorithms.
> 
> 
> I would like to extend it, to include the linearref methods exposed by the
> C API:
>  - GEOSInterpolate
> (- GEOSInterpolateNormalized)
>  - GEOSProject
> (- GEOSProjectNormalized)

Good idea to extend the QgsGeometry API.

> and other buffer methods like GEOSSingleSidedBuffer

Ehm, please call it OffsetCurve (single-sided buffer was a wrong name,
and means a buffer on a single side [areal result]).

> For now I will use the geos_c lib throug ctypes, but supporting some more
> GEOS C/API methods directly from C++ would remove a lot of overhead and
> would speed up performance, obviously.

Why don't you extent QgsGeometry API ?

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