[gdal-dev] OGRCircularString - full circle from three points

[Martin Landa]

Hi,

2015-01-15 11:20 GMT+01:00 Even Rouault <even.rouault at spatialys.com>:
> You can describe a full circle with 3 points by specifying (P1,P2,P1) where
> P1-P2 defines a diameter of the circle, but there's an ambiguity on the
> orientation to follow the CircularString (which shouldn't matter if the
> CircularString is part of a CurvePolygon) and some implementation might not like
> it (OGR should be fine)
> Indeed using 5 points is better. You can define (P1,P2,P3,P4,P1) where all
> points are on the circle. For example P1-P3 and P2-P4 being 2 diameters, but
> that's not a requirement.

thanks for the confirmation Even.

Martin

-- 
Martin Landa
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