[Geojson] Question regarding RFC 7946

Andrew Harvey <andrew@alantgeo.com.au> Mon, 12 March 2018 11:31 UTC

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From: Andrew Harvey <andrew@alantgeo.com.au>
To: geojson@ietf.org
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Date: Mon, 12 Mar 2018 22:31:00 +1100
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Subject: [Geojson] Question regarding RFC 7946
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The spec says:

> For Polygons with more than one of these rings, the first MUST be the
> exterior ring, and any others MUST be interior rings. The exterior
> ring bounds the surface, and the interior rings (if present) bound
> holes within the surface
So does that mean that a Polygon geometry which has two interior rings
where one falls inside another shouldn't create an island within a hole
rather the smaller interior ring contained by the larger one becomes
nullified?
That is, the rendering we see at
https://gist.github.com/andrewharvey/c092a6c4932a4d94ecb6cd59dc935b90 is
wrong and it shouldn't show an island in the middle?
This arose when thinking about
https://github.com/Turfjs/turf/issues/1305
Many thanks,
--
Andrew Harvey
CEO
*Alantgeo*

www.alantgeo.com.au
https://au.linkedin.com/in/andrewharveyau
@alantgeo[1]


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